Introduction
- Nathan A. Mall, MD
- Bryan M. Saltzman, MD
- Andrew S. Lee, MD
- Brian J. Cole, MD, MBA
- Bryan M. Saltzman, MD
Epidemiology
Age
- •
Approximately 4% to 5% of the general population is thought to have focal, full-thickness cartilage defects.
- •
Prevalence is higher in those undergoing arthroscopy, with one study finding 63% with chondral lesions, of which 19% were full thickness.
- •
- •
A systematic review by Flanigan et al. of 11 databases with athletes age 26 to 47 years (mean age of 33 years) demonstrated an overall prevalence of 36% for full-thickness focal chondral defects.
- •
DeHaven et al. noted that athletes treated for internal derangement of the knee at University of Rochester Section of Sports Medicine over a 7-year period had a mean age of 22.9 years.
- •
Namdari et al. analyzed 24 National Basketball Association (NBA) players between 1997 and 2006 and demonstrated a mean age of 28.6 years (range, 21 to 40) at which the athletes presented for surgical intervention of knee articular cartilage injury.
- •
Osteochondritis dissecans (OCD) has its prevalence highest in the 10 to 15 years age group; of note, in this demographic, 15% to 30% of cases involve bilateral knees.
Sex
- •
Kujala et al. noted the risk of knee osteoarthritis (OA) is five times higher in male former top athletes with previous knee injury than in the general population.
- •
Piasecki et al. examined differences among high school athletes, determining that female basketball players sustained fewer cartilage lesions at the knee compared with males, yet there were no cartilage differences by gender with soccer or skiing.
- •
Stevenson et al. demonstrated that in a cohort of 404 competitive alpine ski racers, female racers were 2.3 times more likely to have sustained a knee injury than were their male counterparts.
Sport
- •
Cartilage lesion location may be related to the player’s sport.
- •
Patellofemoral lesions are more common in basketball players, likely caused by contact forces from repeated jumping.
- •
Increased participation by youth in such “cutting” (agility) sports as soccer, basketball, and football have reportedly increased the incidence of knee injuries.
- •
- •
In elite soccer players, 48% of lesions were found on the medial femoral condyle, 23% on the lateral femoral condyle, and 29% in the patellofemoral compartment.
- •
MRIs of collegiate and professional basketball players have demonstrated that 41% to 50% of players had abnormalities in their articular cartilage.
- •
With 20 NBA players (40 total knees) from 1996 to 1999, Kaplan et al. noted a prevalence of 47.5% for knee articular cartilage lesions.
- •
In elite basketball players, the prevalence of asymptomatic articular cartilage lesions at the patellofemoral joint is from 35% to 41%.
- •
- •
40.6% of retired NFL players under the age of 60 years reported arthritis of the knee in comparison with 11.7% of the general male population.
- •
A retrospective review of all National Football League (NFL) players between 1992 and 2006 revealed 118 knee articular cartilage injuries.
- •
During the 3-year period from 2005 to 2007, Hirshorn et al. noted a prevalence of 20.1% for chondral injuries in the nation’s top collegiate football players who had been asked to the NFL combine (a recruitment opportunity for players to display their abilities to prospective NFL teams).
- •
In the 2005 NFL combine alone, Bradley et al. reported that 2.4% of all football players (8 of 333) had osteochondral defects at the knee on initial medical evaluation.
- •
- •
The knee joint is the most common joint injured in competitive alpine ski racing.
- •
In a study by DeHaven et al., seven athletes with track injury sustained internal derangement of the knee (7.5% of total track injuries in this cohort) compared with eight athletes with baseball injury (10.3% of total baseball injuries in this cohort).
Position
- •
In evaluation of NFL combine athletes, the greatest prevalence of knee chondral injury was found with linebackers (32.2%), whereas the lowest prevalence of knee chondral injury was found with defensive backs (12.9%).
- •
Of note, linebackers in the Hirshorn et al. report had the highest average body mass index (BMI) (31.9 kg/m 2 ), which in addition to this particular position’s physical demands may help explain the high prevalence of articular cartilage injury in this football position.
- •
- •
In their analysis of 118 NFL players’ articular cartilage injury between 1992 and 2006, Brophy et al. also reported that linemen had the greatest number of cartilaginous lesions (37% of total cohort).
- •
Namdari et al. analyzed a cohort of 24 NBA players comprised of 11 guards, 10 forwards, and 3 centers who had knee articular cartilage damage.
- •
Thus those positions that require fast cutting and agility movements over the course of a game seem to be overrepresented in this injury type.
- •
Pathophysiology
Intrinsic Factors
- •
Athletes can suffer cartilage injury following repetitive microtrauma secondary to overuse or abnormal joint demands.
- •
Cartilage defects in younger athletes are typically caused by acute traumatic injury or injury secondary to osteochondritis dissecans (OCD).
- •
The articular cartilage organization is similar to that of an open physis, and injuries likewise typically occur through the zone of provisional calcification.
- •
- •
The cause of OCD is not delineated, with avascularity, repetitive trauma, and genetics all cited as independent causes; it may be multifactorial.
- •
Genetic predisposition is a factor for articular cartilage injury, particularly with osteochondritis dissecans.
- •
Subchondral bone biomechanics plays a role in development of osteochondritis dissecans if the subchondral bone remains devascularized, which then subsequently fragments and increases mobility of the bone and overlying articular cartilage.
- •
- •
Joints that naturally have irregularly shaped articular surfaces are more likely to be injured in young athletes because of asymmetric loading and wearing patterns.
- •
Increased BMI is strongly associated with knee articular cartilage injury in NFL quarterbacks, offensive tackles, and defensive backs.
- •
Research shows that young athletes with BMI greater than 30.5 kg/m 2 and weight greater than 222.5 lbs are at significantly increased risk for knee chondral damage.
- •
However, height is not a significant independent risk factor for cartilage injury.
- •
- •
Full-thickness cartilage defects do not heal and are likely to expand circumferentially over time; however, the natural history of cartilage defects has not been well studied.
Extrinsic Factors
- •
Participation in competitive sports, causing high intensity, direct joint impact
- •
Consecutive arthroscopies (993) in Norway noted full-thickness cartilage lesions in 11% of knees, with sports participation as the most reported activity (49%).
- •
- •
Delay in surgery
- •
Church and Keating noted an increase in degenerative changes in patients operated on with more than 12 months delay after injury as compared with less than 12 months delay.
- •
- •
Intense physical activity and high-level sports contribute to osteochondritis dissecans.
Traumatic Factors
- •
Traumatic cartilage damage is often found in the setting of an anterior cruciate ligament (ACL) tear.
- •
Several studies have found changes in cartilage thickness and proteoglycan content in both the lateral and medial compartment following ACL injury.
- •
- •
Fractures involving the articular surface necessitate precise reduction and fixation; 3-mm incongruities in the surface may involve increased local contact stress leading to OA posttraumatic OA.
- •
Abrasive wear on the knee joint with continued athletic activity results in superficial fibrillation of the cartilage, which progresses to subchondral bone.
- •
Acute, large shear force as a sudden traumatic experience can disrupt the deep cartilage ultrastructure at the knee joint, ultimately damaging the cartilage.
- •
Athletics with high levels of torsional loading, twisting, pivoting, rapid deceleration, and high impact forces increase susceptibility to developing articular cartilage damage owing to the effects of these combating force vectors on the integrity of the knee joint.
- •
The NFL linebacker position must quickly pivot and exert lower extremity force in the course of a game; these rapid shear forces are proposed to be the cause for articular damage in this cohort.
- •
Articular cartilage injuries in soccer players are hypothesized as follows :
- •
Extreme stresses befall the articular cartilage of the knee with the combination of high movement velocity and abrupt deceleration.
- •
- •
Articular cartilage injuries in basketball players are hypothesized as follows :
- •
Plyometric jump training (an important component of competitive basketball) involves a strong contraction-extension mechanism at the patellofemoral joint.
- •
Repetitive jumping causes repetitive stresses at the joint, which may cause patellofemoral joint damage at the articular cartilage.
- •
- •
OCD in the elbow is typically seen more frequently in those that subject the elbow to repetitive trauma (gymnasts, pitchers); however, this relationship is not as obvious in OCD of the distal femur or talus.
Classic Pathological Findings
(See Figures 31-1 to 31-3 .)
- •
MRI demonstrates a typical focal cartilage defect with adjacent bone edema on T2-weighted MRI sequence.
- •
Injury to articular cartilage in youth athletes occurs through the zone of provisional calcification at the joint.
- •
In a full-thickness chondral injury, chondrocytes increase synthesis of extracellular matrix in an effort to repair the damaged section of cartilage.
- •
The healing response to a full-thickness chondral injury begins with hematoma formation, followed by stem cell migration to produce type I collagen and allow vascular growth—note that this “healed cartilage” is less resilient to shear forces, easily damaged, and more likely to result in OA than is the original hyaline cartilage layer.
- •
Outerbridge Classification of Cartilage Lesions
- •
Grade 0: Normal
- •
Grade 1: Intact surface cartilage with softening and swelling
- •
Grade 2: A partial-thickness defect with fissures on the surface that do not reach subchondral bone or exceed 1.3 cm in diameter
- •
Grade 3: Fissuring to the level of subchondral bone in an area with a diameter greater than 1.3 cm
- •
Grade 4: Exposed subchondral bone
- •
- •
Chondral lesions are painful because the nerve endings of the subchondral bone after injury to overlying articular cartilage become stimulated by the forces now faced by denuded bone.
- •
Cartilaginous lesions that are full thickness can worsen as a result of structural changes in subchondral bone, intraarticular inflammatory cytokine release post damage, and stress forces concentrated around the rim of a chondral defect.
Clinical Presentation
History
- •
Typically pain is present with weight bearing.
- •
Mechanical symptoms can be present if there is a flap of cartilage, a large cartilage defect, or a loose body.
- •
Swelling is classically reported with increased activity.
- •
Aching of joint after standing or during/after periods of inactivity
- •
Stiffness after periods of inactivity
- •
Sensation of “giving way”
- •
Sensation of “catching”
- •
Pain with stairs and steps, bent knee activity, and stiffness rising from a seated position can be present with patellofemoral cartilage defects, but characteristically also are associated with swelling.
- •
Levy et al. reported from studies in young soccer players that the specific motions causing pain from chondral lesions were dependent on the location of the injury.
- •
Patellar/trochlear lesions: pain with jumping, deceleration, extension phase of kicking
- •
Anterior condylar lesions: pain with extension phase of kicking
- •
Central condylar lesions: pain during pivoting, lateral movements
- •
Posterior condylar lesions: pain with flexion phase of kicking, planting of the nonkicking leg
- •
- •
In osteochondritis dissecans, patients often present with effusion, catching/locking (especially if loose body is present in the joint), and anterior knee pain.
- •
Adolescents with osteochondritis dissecans can, however, have vague symptoms.
- •
- •
Some athletes will complain of a specific traumatic event from which the symptoms arose (i.e., slide tackle in soccer), whereas others will complain of insidiously progressive symptoms.
Physical Examination
Abnormal Findings
- •
Swelling is a frequent sign of cartilage injury.
- •
Condyle defects may or may not have joint line tenderness, but frequently have tenderness to palpation on the medial or lateral condyle.
- •
Patellar or trochlear defects can present with anterior knee pain.
- •
Reduced active and passive range of motion (ROM) ; may be limited if a loose body is present or a significant effusion is limiting terminal flexion and extension.
- •
Functional strength loss at the knee joint
- •
Crepitus can be evident.
- •
A study by Ike et al. of 20 athletes with knee joint chondral injury demonstrated a sensitivity of 54% with specificity of 100% for transmitted bony crepitus during clinical examination when the joint had tibial bare bone only, and a sensitivity of 88% with specificity of 100% for bone-on-bone rubbing owing to cartilage loss from injury.
- •
- •
In particular, osteochondritis dissecans will demonstrate the following :
- •
Limited ROM
- •
Effusion
- •
Positive Wilson’s test (reproducible pain with internal rotation of the tibia plus passive extension of the knee)
- •
- •
A careful ligamentous examination should be performed because cartilage defects have been associated with ACL and other ligamentous deficiencies.
- •
Must evaluate overall limb alignment, and if clinical concern is present for malalignment, standing pelvis to ankle radiographs should be obtained.
Pertinent Normal Findings
- •
In the absence of concomitant ligamentous damage, there should be no increased ligamentous laxity on examination in comparison with the contralateral knee.
Imaging
- •
Plain radiographs can
- •
Help differentiate between more diffuse cartilage loss
- •
Identify an OCD and/or a loose body if enough bone is present on the loose fragment
- •
- •
X-rays are an important primary tool for assessment of the knee joint.
- •
Those with K&L (Kellgren and Lawrence classification) grade 2 or more defined as OA
- •
X-ray grading: Grade 0, no changes; Grade 2, definite osteophytes and possible narrowing of joint space; Grade 3, moderate multiple osteophytes, definite joint space narrowing, sclerosis and deformity; Grade 4, large osteophytes, marked narrowing of joint space, severe sclerosis and deformity of bone ends ( Figure 31-4 ).
FIGURE 31-4
Radiographs with alternate views are important in delineating pathology and any observable changes: ( A ) Anteroposterior; ( B ) Lateral; ( C ) Merchant view.
- •
Evidence of osteochondritis dissecans lesions can be viewed with X-ray, most commonly on the lateral portion of the medial femoral condyle, and should be evaluated with standard weightbearing AP, lateral, and Merchant views ( Figure 31-5 ).
FIGURE 31-5
Full body radiograph from pelvis to ankle allows for noting limb alignment, varus or valgus angulation.
- •
- •
Bilateral standing alignment radiographs should be obtained when clinical concern for varus or valgus alignment is present.
- •
Weightbearing axis from the center of the femoral head to the midbody of the talus should be drawn and its intersection with the tibial plateau noted.
- •
If this line falls into zone 2 or 3, realignment should be considered in the setting of a cartilage defect.
- •
In some cases weightbearing axes falling into zone I may also benefit from realignment.
- •
- •
MRI can be used to
- •
Confirm the diagnosis
- •
Better define the cartilage lesion size and depth
- •
Identify any concomitant pathology such as a meniscal tear which may mimic an articular cartilage defect on examination
- •
Identify subchondral edema
- •
- •
MRI is a valuable tool for evaluation of cartilage surface, tissue thickness, and subchondral bone signal intensity at the knee joint.
- •
Accuracy of 90% in evaluating cartilage injury in comparison with gold standard arthroscopy
- •
Sequences utilized in assessing chondral pathology at the knee are T2 or intermediate (proton density) weighted fast spin-echo sequences.
- •
Demonstrates chondral injury as regions of linear fissuring and surface irregularities with high signal joint fluid visible in the chondral defect
- •
Depth, location, and size of the cartilage injury, as well as any concomitant bony or ligamentous damage can be determined through this means of imaging ( Figure 31-6 ).
FIGURE 31-6
MRI T2 Coronal view of meniscal injury with subchondral edema on the femoral condyle.
- •
MRI grading
- •
Grade 1, abnormal intrachondral signal but normal chondral surface
- •
Grade 2, mild surface irregularity and/or focal loss of less than 50% thickness
- •
Grade 3, severe surface irregularity with focal loss of 50% to 100% thickness
- •
Grade 4, complete loss of articular cartilage with exposure of subchondral bone ( Figure 31-7 ).
FIGURE 31-7
MRI of a 28-year-old physically active male reporting medial compartment pain with past history of skating injury, subchondral edema, and changes noted ( A – C ).
- •
- •
- •
The gold standard imaging study for knee cartilage injury is arthroscopy.
- •
Per Bachmann et al., the sensitivity for determining chondral injury with arthroscopy increases in proportion to the grade of the defect: I is 14%, II is 32%, III is 94%, IV is 100% ( Figures 31-8 and 31-9 ).
FIGURE 31-8
Arthroscopic display ( A ) and examination ( B ) of a grade IV (full-thickness) articular cartilage defect, located at the medial femoral condyle
FIGURE 31-9
Grade IV lesion ( arrow ) of a 21-year-old female athlete with meniscal deficiency.
- •
Differential Diagnosis
- •
Patellofemoral pain and cartilage defects of the patella or trochlea can produce similar symptoms.
- •
Typically, these can be differentiated by the presence or absence of swelling.
- •
- •
Generalized arthritis not amenable to cartilage restoration or repair
- •
Synovial impingement syndrome
- •
Pathologic plica
- •
Pain aggravated by knee flexion and relieved with extension
- •
Examination may reveal a thick, palpable cord
- •
Normal radiographs, MRI with prominent plica
- •
- •
Hoffa syndrome
- •
Swelling in the region of the knee fat pad
- •
Tender to palpation in area of the fat pad
- •
Positive Hoffa maneuver: apply compression to the sides of the fat pad while bringing knee into extension, causing pain/apprehension
- •
- •
- •
Osteochondroses/tendinitis (common in young athletes)
- •
Osgood-Schlatter
- •
Tenderness, swelling, bony prominence evident around tibial tuberosity
- •
- •
Sinding-Larsen-Johansson
- •
Tender to palpation focally near inferior pole of the patella
- •
- •
Patellar tendinitis
- •
Pain focally in inferior pole of patella exacerbated by activity or palpation
- •
Occurs often after a period of increased activity, intensity of sports training
- •
Symptoms begin during activities only, but progress to occur with ADLs
- •
Pain elicited on examination with decline squat test, which focuses stress on the patellar tendon
- •
- •
- •
Hip pathology
- •
For example, slipped capital femoral epiphysis, stress fracture
- •
May present with referred pain to the knee joint
- •
Significant pain at the hip when examined, which will not occur in the instance of focal knee cartilaginous injury
- •
- •
Tumors
- •
For example, osteosarcoma, osteoid osteoma
- •
Insidious onset not attributable by patient to any specific trauma from athletic endeavors
- •
Will be evident with radiographic examination
- •
- •
Meniscus tear
- •
Patient can often relay an instance during sport activities when he/she experienced a traumatic twisting movement at the knee while the knee was bent.
- •
Maneuvers post injury that mimic this motion (such as getting out of a car) will elicit pain.
- •
Examination demonstrates pain with squatting, positive McMurray test (pressing on joint line while stressing the meniscus), and present Cooper’s sign (reported pain with turning over in bed at night).
- •
- •
Ligamentous injury
- •
Instability is the major complaint
- •
Many different examination techniques can deduce which ligament has sustained damage (Lachman test, anterior drawer test, pivot shift test, etc.).
- •
Treatment
Nonoperative Management
- •
Nonsteroidal antiinflammatory medications
- •
Local ice/heat therapies
- •
Bracing, crutches to prevent weight bearing
- •
Weight reduction has the best evidence for improvement in pain and function
- •
Activity modification, such as resting from athletic activities
- •
Oral nutraceutical agents such as chondroitin sulfate, glucosamine, hyaluronic acid-based products either orally or by injection (have not be shown to be a cost-effective treatment)
- •
Physical therapy for strengthening of the core, quadriceps; stretching of the anterior hip, hamstrings
- •
Physical therapy can help strengthen the extremity and facilitate weight loss.
- •
Guidelines for Choosing Among Nonoperative Treatments
- •
Asymptomatic partial-thickness chondral injuries can be managed conservatively.
- •
Undisplaced intact chondral lesions may be treated nonsurgically.
- •
Osteochondritis dissecans deemed stable can be managed nonsurgically.
- •
Failure of conservative therapy with continued pain and symptoms related to the cartilage defect
- •
Patients can have patellofemoral pain or pain related to other pathology intrinsic or extrinsic to the knee, which should be monitored.
- •
Surgical Indications
- •
Relative indications
- •
Symptomatic (pain, swelling) partial-thickness or undisplaced intact chondral lesions
- •
- •
Absolute indications
- •
Those injuries that fail conservative treatment
- •
Unstable lesions
- •
Aspects of History, Demographics, or Exam Findings that Affect Choice of Treatment
- •
Length of time symptoms have been present has demonstrated an inverse relationship with outcomes.
- •
Patient age is a significant prognostic factor, but may be more related to physiologic age rather than chronologic age.
- •
Activity level and size of the lesion are factors in algorithms to determine treatment for symptomatic cartilage defects.
- •
Improved results have been demonstrated in patients with BMI less than 30.
- •
Indications for specific surgical interventions
- •
Microfracture surgery
- •
For small, symptomatic articular cartilage lesions
- •
Minimal costs in comparison to other techniques for those patients for whom invasive techniques are required but finances are an issue ( Figure 31-10 ).
FIGURE 31-10
A 15-year-old male runner with past history of lateral right knee pain received microfracture of lateral tibial plateau as seen by ( A ) coronal and ( B ) sagittal MRI images.
- •
- •
Autologous chondrocyte implantation (ACI)
- •
Requires a high level of patient compliance (involves 2 operations); best treatment for patients adherent to medical regimens and requests
- •
Prolonged recovery time including many weeks of non–weight-bearing
- •
- •
Autologous and allogeneic osteochondral transplants
- •
Full-thickness osteochondral lesions if the knee is well-aligned and entirely stable on physical examination ( Figure 31-11 ).
FIGURE 31-11
Osteochondral allograft to MFC in a 37-year-old male athlete with recurrent knee pain displaying excellent integration ( arrows showing regions of integration).
- •
- •
Aspects of Clinical Decision Making When Surgery Is Indicated
- •
Best surgical treatment option must be chosen for the athlete based on expected time to recovery, and patient adherence to pre- and postsurgical demands (i.e., physical therapy).
- •
Staging arthroscopy and ACI biopsy better delineate lesion size and location, depth, and concomitant pathology within the knee.
- •
Lesions amenable to microfracture or osteochondral autografting can be performed at the time of staging arthroscopy
- •
Some studies demonstrate that prior microfracture or other treatment may reduce the efficacy of ACI following clinical failure, leaving osteochondral allograft as the treatment of choice in most revision settings.
- •
- •
Significant bony injury noted as bone edema on MRI warrants a procedure that addresses both injuries: either an osteochondral autograft for smaller lesions or osteochondral allograft for larger lesions.
- •
Deeper lesions typically respond better to allograft or autograft fill; however, “sandwich” ACI techniques have been described with relatively good reported results.
- •
- •
Microfracture, ACI, and other cell-based therapies have demonstrated reduced efficacy in patients with prolonged symptoms (greater than 1 year) or multiple prior procedures, which may influence the decision to use an osteochondral allograft.
- •
Patellofemoral defects are difficult to fill with osteochondral autograft or allograft because of the complex morphology that is patient specific despite adequate sizing ( Figure 31-12 ).
FIGURE 31-12
Osteochondral autograft transplantation (top) site of lesion before and (bottom) postimplantation.
- •
Lateral patellar facet lesions are typically treated with a concomitant anteromedialization of the tibial tubercle to help offload this area of the compartment, whereas medial facet lesions may benefit from a more vertical osteotomy and straight anteriorization ( Figure 31-13 ).
FIGURE 31-13
Radiograph of ACL reconstruction with BPTB autograft and prior history of right anteromedialization procedure.
- •
Loose bodies derived from OCD lesions of the weight-bearing aspects of the femoral condyles may be amenable to fixation despite having relatively little bone on the loose fragment. Likelihood of healing is higher in younger individuals
- •
A survey among NFL team physicians by Brophy et al. regarding knee articular cartilage injury demonstrated the following:
- •
The most popular treatment for this type of injury was microfracture (43.3% of team physicians), second debridement (31.4%), then nonoperative management (13.2%), mosaicplasty (6%), osteochondral allograft (3.5%), and ACI (2.6%).
- •
Size of the chondral injury was the most important factor to these physicians in making decisions about surgical management.
- •
Evidence
Multiple-Choice Questions
- QUESTION 1.
A 21-year-old woman presents to her doctor with complaints of progressively worsening right knee pain since an episode of trauma while engaged in an athletic competition against her brother. It is determined through physical exam and imaging techniques that she has sustained damage to the articular cartilage of her right knee. In which of the following sports would she be more than twice as likely to sustain knee injury as compared to her brother?
- A.
Softball
- B.
Alpine ski racing
- C.
Squash
- D.
Ice skating
- A.
- QUESTION 2.
A 6 foot 8 inch collegiate football starting offensive tackle, weighing in at 320 lbs, presents to the team orthopedic surgeon with complaints of swelling and catching in his left knee. The symptoms have been present since his freshman year of college (he is currently a junior) and have not changed much in character. His father played in the NFL for 13 years also as an offensive tackle, and is left with osteoarthritis in his bilateral hips and knees. Which of the following is NOT an independent risk factor for the development of chondral injury in this athlete?
- A.
His BMI
- B.
Weight
- C.
Genetics
- D.
Height
- A.
- QUESTION 3.
A 14-year-old female soccer player complains to her physical therapist of new-onset left knee pain after kicking the soccer ball with enough force to fly 100 feet in practice 2 days ago. Which of the following collagen types is most likely being produced at this time at the site of injury by the patient’s migrating stem cells?
- A.
Type I
- B.
Type II
- C.
Type III
- D.
Type IV
- A.
- QUESTION 4.
A 23-year-old professional NBA basketball player presents to the team orthopedic surgeon after landing awkwardly on his right knee in practice earlier that day. His doctor decides to order an MRI of the right lower extremity. Evaluation of the images demonstrates a mild irregularity at the chondral surface with loss of 32% thickness by computer measurements. What MRI Grade would this lesion be deemed?
- A.
Grade 1
- B.
Grade 2
- C.
Grade 3
- D.
Grade 4
- A.
- QUESTION 5.
A 16-year-old recreational basketball player presents to the monthly free orthopedic clinic at his local hospital. He had been given an appointment to return for a follow-up of his right knee pain 6 months ago, after he first presented with symptoms of joint pain and swelling 7 months ago. The patient reports that he hasn’t been able to come in because he has to work 70 hours a week as a waiter to keep his job and pay to stay in his apartment. Now that he has finally returned the doctor orders an MRI of his right knee, which demonstrates a small chondral lesion of the articular cartilage. After discussing many different treatment options, it is decided that surgery will be performed. Which of the following is the most appropriate surgical intervention for this patient?
- A.
Microfracture
- B.
Autologous Chondrocyte Transplantation
- C.
Autologous Osteochondral Transplant
- D.
Allogeneic Osteochondral Transplant
- A.
Answer Key
- QUESTION 1.
Correct answer: B (see Epidemiology—Sex )
- QUESTION 2.
Correct answer: D (see Pathophysiology—Intrinsic Factors )
- QUESTION 3.
Correct answer: A (see Pathophysiology—Classic Pathologic Findings )
- QUESTION 4.
Correct answer: B (see Clinical Presentation—Imaging Studies )
- QUESTION 5.
Correct answer: A (see Treatment )
Nonoperative Rehabilitation of Articular Cartilage Injuries
- Andreas H. Gomoll, MD
- Reginald B. Wilcox, PT, DPT, MS OCS
- •
Individualization
- •
Interdisciplinary team approach
- •
Restore the biomechanics of the knee
- •
Minimize pain and joint effusion
- •
Restore muscle function
- •
Restore soft tissue length
- •
Enhance proprioception and neuromuscular control
- •
Control loads across the lower extremity
Introduction
- •
These guidelines are for the postinjury rehabilitation course of a patient that has sustained an articular cartilage injury or undergone a restorative procedure. It is by no means intended to be a substitute for one’s clinical decision making regarding the progression of a patient’s postoperative course based on their physical exam/findings, individual progress, and/or the presence of postinjury complications. If a clinician requires assistance in the progression of a postinjury patient he or she should consult with the referring physician.
- •
The timelines are approximate ranges. The treating clinician should take into consideration patient/athlete presentation and achievement of clinical milestones in each phase.
- •
The acutely injured athlete will likely start with phase I of this guideline. However, the athlete who has been experiencing more of a subacute or chronic knee injury as the result of an articular cartilage lesion may begin this rehabilitation plan in phase II if pain and effusion are minimal and the athlete demonstrates little to no range of motion impairments.
- •
Following an articular cartilage injury, continuous monitoring of pain and effusion in response to all activity progression (exercise, weight-bearing, etc.) is vital to a successful rehabilitation process.
Phase I (weeks 0 to 4)
Protection
- •
Protected weight bearing with crutches is recommended to reduce the mechanical forces through the knee, to allow for a reduction in pain and effusion. The length of crutch use is determined by the location and severity of the lesion. Typically the individual with a large lesion on a weight-bearing surface of the knee will require a longer protected weight-bearing period.
- •
If patients present with a concomitant ligamentous injury, a significant inhibition of quadriceps function, and/or require some additional support beyond protected weight bearing, drop-lock rehabilitative hinged knee bracing is indicated to provide adequate stability to the knee during the acute phase of recovery and rehabilitation. If such a brace is needed, it would be locked in full extension for weight bearing activities and unlocked for non–weight-bearing activities.
- •
Individuals with persistent knee joint effusion may benefit from a compressive knee sleeve to assist in controlling effusion both during activities of daily living as well as exercise progression.
| PHASE I (weeks 0 to 4) | PHASE II (weeks 4 to 8) | PHASE III (weeks 8 to 12) | PHASE IV (weeks 12 +) |
|---|---|---|---|
|
|
|
|
Management of Pain and Swelling
- •
The reduction of pain and joint effusion is crucial for restoring normal quadriceps function.
- •
Treatment for pain/effusion
- •
Cryotherapy (continuous cool system or ice packs) ( Figure 31-14 )
FIGURE 31-14
Cryotherapy and intermittent compression applied through a continuous cool device (Gameready; Coolsystems Corporation, Berkeley, CA) with elevation for effusion management.
- •
Elevation
- •
High-voltage electrical stimulation
- •
Cold laser
- •
Compressive knee sleeve
- •
Transcutaneous electrical nerve stimulation
- •
Controlled passive range of motion
- •
Analgesic and antiinflammatory medication. The latter can be contraindicated after certain procedures such as osteotomy and cartilage transplantation.
- •
Techniques for Progressive Increase in Range of Motion
- •
The early restoration of normal patellofemoral as well as tibiofemoral range of motion (ROM) is crucial to creating an optimal environment of healing for the knee.
- •
Specifically full knee extension, which for some individuals means a few degrees of hyperextension, is needed to ensure normal joint arthrokinematics to reduce patellofemoral and tibiofemoral contact pressure as well as minimize strain and fatigue of the quadriceps. Full knee extension should be achieved within the first 2 weeks of therapy.
- •
Unless a mechanical block is noted, knee flexion range of motion typically will gradually progress toward normal as pain and effusion resolve.
- •
When regaining ROM following an articular cartilage injury it is important to not introduce shear forces while the joint is under compression, as this may have adverse effects on the lesion. ROM exercises should be done in a controlled manner. Evidence from both human and animal studies following articular cartilage repair supports early active and passive motion exercises to enhance tissue healing and reduce the potential risk of adhesions. Unloading and immobilization have been reported to have a negative effect on the healing of articular cartilage. Hence it is advised following an articular cartilage lesion that is going to be managed conservatively that one begins a controlled progressive range of motion program to promote healing and prevent further injury or degeneration.
- •
If an individual has access to a pool, it is recommended that aquatherapy be part of the rehabilitation plan. The buoyancy factor of water significantly decreases the amount of weight-bearing forces during pool exercises compared with land exercise. After surgery, aquatherapy should be delayed until wound healing has occurred, usually after 2 weeks.
Manual Therapy Techniques
- •
Medial-lateral patella mobilizations performed by the therapist and patient to restore normal patella mobility
- •
Superior-inferior patella mobilizations performed by the therapist and patient to restore normal patella mobility ( Figure 31-15 )
FIGURE 31-15
Therapist performed medial-lateral ( A ) and superior-inferior ( B ) patella mobilizations to enhance patella femoral motion.
- •
Tibiofemoral and tibiofibular mobilizations directed at restoring normal motion performed by the therapist
Soft Tissue Techniques
- •
Soft tissue mobilization is performed to prevent the development of scar tissue/adhesions from forming.
Stretching and Flexibility Techniques for the Musculotendinous Unit
- •
General flexibility exercises performed by the therapist and patient to restore normal length of musculotendinous units
- •
Hamstrings
- •
Gastrocnemius/soleus
- •
Hip abductors/adductors
- •
Hip flexors
- •
Quadriceps (once good quadriceps muscle function is restored and joint effusion is minimal)
- •
- •
If an individual is having difficulty regaining the appropriate muscle length/integrity through therapist and self-guided stretching alone, then modalities such as moist heat and ultrasound may be used as an adjunctive intervention to facilitate greater gains.
Other Therapeutic Exercises
- •
During phase I of rehabilitation injured athletes should actively participate in core stability strengthening, their typical upper body strengthening routine, and a cardiovascular conditioning program as their injured knee allows. Their injured knee should be supported and protected from further injury during all exercise.
Activation of Primary Muscles Involved
- •
Initially quadriceps muscle function restoration is key to early rehabilitation. The injured athlete should commence quadriceps sets, straight leg raises (begin with the locked knee brace if there is an active extension lag, then discontinue the brace for exercise when no lag is present), short (SAQ) and long arc (LAQ) AROM exercises. A/AA/PROM of knee to full extension and flexion as tolerated (avoid active knee extension (SAQ, LAQ, etc.) for 3 to 4 weeks if patellofemoral lesion is present); when active knee extension exercises are initiated they need to be completed within a range of motion that does not engage or compress the lesion. Hence it is important for the therapist and surgeon to communicate regarding the location of the lesion.
- •
If one is having difficulty initiating and/or maintaining an adequate quadriceps contraction with any of these exercises, the use of neuromuscular electrical stimulation (NMES) and/or biofeedback is indicated ( Figure 31-16 ).
FIGURE 31-16
Neuromuscular electrical stimulation (300PV; Empi Corporation, St Paul, MN) applied to the quadriceps muscle during quadriceps sets ( A ) and straight leg raises ( B ).
- •
It is imperative that the injured athlete and the therapist make sure to not solely focus on the quadriceps. A balanced strengthening approach is needed to restore appropriate lower extremity function. A gradually progressed program of trunk, hip, and ankle exercises is needed to control normal lower extremity forces and excess forces through the injured knee.
- •
Lower extremity musculature needs to become strong following articular cartilage injury, to assist in absorbing normal lower extremity shock and dissipating applied loads across the knee joint.
- •
Throughout the early rehabilitation course, strengthening exercises should be chosen appropriately in order to minimize high sheer stress in conjunction with compressive forces. Hence the start of closed chain therapeutic exercises is delayed.
Open and Closed Kinetic Chain Exercises
- •
Closed kinetic chain (CKC) exercises: Typically not indicated in the first phase of rehabilitation because of the weight-bearing stress they incur across either the femoral or tibia lesion following the acute injury.
- •
Open kinetic chain (OKC) exercises
- •
A/AA/PROM of knee to full extension and flexion as tolerated. (Avoid active knee extension for 3 to 4 weeks if patellofemoral lesion is present; and for more than 6 months after cell-based cartilage repair in the patellofemoral joint to allow for tissue maturation.)
- •
Hip, hamstring, calf stretching
- •
4-way ankle strengthening with elastic band
- •
Quadriceps sets
- •
Multiangle quadriceps/hamstring isometric contractions to start at 90° of flexion, as it is unlikely to produce excessive compressive or shear forces across most articular cartilage lesions. Caution is recommended with any isometric contractions between 20° and 75°, as there may be high compressive forces on most lesions in this range.
- •
4-way straight leg raises
- •
Supine
- •
Side lying for abductors
- •
Side lying for adductors
- •
Prone
- •
- •
Stationary bike without resistance if greater than or equal to 95° to 100° of flexion
- •
Techniques to Increase Muscle Strength, Power, and Endurance
- •
To enhance the overall muscular function of the hip and knee musculature, it is advisable to work with a high-repetition low load to enhance muscular endurance and reduce the risk of injury. When progressing such exercises as the 4-way straight leg raises, athletes are advised to work up to 2 to 3 sets of 15 to 20 reps with no knee extension lag. When able to complete up to 60 repetitions in total, a progression in load (i.e., adding ankle weights in 1-lb. increments) is indicated.
Functional Exercises
- •
Gait training with crutches with protected weight bearing
- •
Encourage gradually progressed periods of time on feet with crutches to promote a return to daily activities.
Milestones for Progression to the Next Phase
- •
Minimal to no knee joint line tenderness
- •
Minimal knee pain at rest and/or light activities
- •
A steady reduction in knee joint effusion with no persistent effusion following progressively more challenging activities of daily living and/or therapeutic activities
- •
Full knee extension ROM comparable with the contralateral knee
- •
At least 120° of knee flexion
- •
Normal passive and active patellofemoral mobility. Passive patella mobility is assessed with the patient’s knee in a relaxed and extended position. Active patella mobility is assessed during functional activities.
- •
Adequate quadriceps control (i.e., able to do at least 15 to 20 straight leg raises without a brace or lag and able to ambulate household distances with least assistive device with natural knee flexion and extension ROM).
Phase II (weeks 4 to 8, depending on lesion size and location)
- •
Note on rehabilitation after cell-based cartilage repair procedures (microfracture, autologous chondrocyte implantation [ACI, Carticel])
- •
Generally speaking, cell-based repair procedures require a slower progression to allow for tissue maturation, which is initially very soft and vulnerable to shear forces. Therefore progression to phase II mostly does not occur until 12 weeks postop, while continuing to focus on restoration of motion and patellar mobility, reduction of swelling, and recruitment of quadriceps and hamstring muscles through isometrics and electrical stimulation.
- •
Protection
- •
At this point in rehabilitation the injured athlete should be ready to progress to weight bearing as tolerated. However, this timeframe will be dictated by the size, nature, and location of the lesion as well as the quantity of ROM restoration and overall muscular strength. In order to begin weaning from bilateral crutches the athlete should have full knee extension, at least 100° of knee flexion, have no lag with a straight leg raise or with walking. He/she may need one crutch or cane in the contralateral upper extremity for some assistance to avoid a pronounced limp for community distances. Those individuals with a large lesion on the weight-bearing surface of the femur may need to stay with bilateral crutches for another week or 2 to minimize pain and joint effusion.
- •
If the athlete has good quadriceps control, the drop-lock rehabilitative hinged knee brace is set for full motion and worn for an additional 2 weeks as he/she progresses overall activity level.
- •
Individuals with persistent knee joint effusion may still benefit from a compressive knee sleeve to assist in controlling effusion during both activities of daily living as well as exercise progression.
Management of Pain and Swelling
- •
If persistent pain and effusion are limiting rehabilitation progress, the continued use of the following interventions is still warranted. However, as each week passes the need for each intervention should be reduced.
- •
Cryotherapy (continuous cool system or ice packs)
- •
Elevation
- •
High-voltage electrical stimulation
- •
Cold laser
- •
Compressive knee sleeve
- •
Transcutaneous electrical nerve stimulation
- •
Controlled passive range of motion
- •
Analgesic medication
- •
Techniques for Progressive Increase in Range of Motion
Manual Therapy Techniques
- •
Continue with medial-lateral patella mobilizations performed by the therapist and patient to restore normal patella mobility if still limited.
- •
Continue with superior-inferior patella mobilizations performed by the therapist and patient to restore normal patella mobility if still limited.
- •
Continue with tibiofemoral and tibiofibular mobilizations directed at restoring normal motion performed by the therapist if still limited.
Soft Tissue Techniques
- •
Continue with soft tissue mobilizations to prevent the development of scar tissue/adhesions from forming if soft tissue integrity has not been normalized.
Stretching and Flexibility Techniques for the Musculotendinous Unit
- •
General flexibility exercises performed by the therapist and patient to restore normal length of musculotendinous unit
- •
Hamstrings
- •
Gastrocnemius / soleus
- •
Hip abductors/ adductors
- •
Hip flexors
- •
Quadriceps stretching is typically appropriate at this stage of rehabilitation as long as there is good quadriceps muscle contraction and normalized patellofemoral movement.
- •
- •
At this stage of rehabilitation the muscle length/integrity should be near normal, and adjunctive modalities such as moist heat and ultrasound are typically not warranted. Continued therapist and athlete guided stretching should be all that is needed to maintain appropriate tissue length.
Other Therapeutic Exercises
- •
During phase II of rehabilitation the injured athlete should continue to actively participate in core stability strengthening, their typical upper body strengthening routine and a cardiovascular conditioning program. Upright and/or recumbent exercise biking should be tolerated easily at this point of rehabilitation. If the injured athlete has successfully transitioned to full weight bearing without an assistive device, the gradual introduction of single line walking on a treadmill or stable ground can be introduced followed by the use of an elliptical trainer.
Activation of Primary Muscles Involved
- •
Continued focus on quadriceps muscle function restoration is crucial to rehabilitation. The injured athlete should be able to do repetitive progressed 4-way straight leg raises with weight and without a lag and the knee brace. Progression toward a graduated bilateral to unilateral leg press machine should commence during phase II to enhance functional quadriceps and general lower extremity strength prior to beginning higher level closed chain therapeutic exercises. It is still important that the injured athlete and their therapist make sure to not solely focus on the quadriceps. A balanced strengthening approach is needed to restore appropriate lower extremity function. A gradually progressed program of trunk, hip, and ankle exercises is needed to control normal lower extremity forces and excess forces through the injured knee.
Sensorimotor Exercises
- •
All the following therapeutic activities would be indicated once the injured athlete has regained appropriate quadriceps control, has little to no effusion, and can tolerate at least partial weight bearing without side effects for up to an hour.
- •
Weight shifting side to side drills
- •
Weight shifting forward and backward drills
- •
Weight shifting diagonal drills
- •
Bilateral mini-squats; limit 0° to 45°
- •
Bilateral minisquats on an unstable surface (wobble board, tilt board, air disc, etc.); limit 0° to 45°
- •
Balance activities onto and off from various unstable surfaces
- •
Open and Closed Kinetic Chain Exercises
- •
OKC exercise
- •
A/AA/PROM of knee to full extension and flexion as tolerated (avoid active knee extension (SAQ, LAQ, etc.) for 3 to 4 weeks if patellofemoral lesion is present); when active knee extension exercises are initiated, they need to be completed within a range of motion that does not engage or compress the lesion. Hence it is important for the therapist and surgeon to communicate regarding the location of the lesion.
- •
Hip, hamstring, calf stretching
- •
4-way ankle strengthening with elastic band
- •
Quadriceps sets
- •
Multi-angle quad/hamstring isometric contractions
- •
4-way straight leg raises
- •
Supine
- •
Side lying for abductors
- •
Side lying for adductors
- •
Prone
- •
- •
- •
CKC exercises: When selecting closed chain exercises for a specific patient, knowledge of the defect location is critical, as it has been shown that different activities require various contacts on the tibiofemoral joint. If the lesion is located in the anterior aspect of the tibiofemoral joint, full knee extension with CKC exercises needs to be avoided. Conversely if the lesion is in the posterior aspect of the joint, loading greater than 45° of flexion with CKC exercises should be initially avoided.
- •
Leg press (allows for graded weight-bearing through the knee) in advance of doing minisquats; limit 0° to 90° ( Figure 31-17 )
FIGURE 31-17
Exercise such as a bilateral leg press assist the athlete in functional lower extremity strengthening while getting used to weight bearing through the involved knee.
- •
Lunges
- •
Step-ups
- •
Step-downs
- •
Stationary bike without resistance if greater than or equal to 95° to 100° of flexion. One needs to make sure the seat height is appropriate for any given lesion. The lower the seat height, the higher the patellofemoral joint compressive forces are. The higher the seat height, the less is the overall knee flexion range of motion. Initially seat height should be set high and then progressively lowered to normal seat height as range of motion progresses.
- •
Techniques to Increase Muscle Strength, Power, and Endurance
- •
To continue to enhance the overall muscular function of the hip and knee musculature, it is advisable to work with a high-repetition low load to enhance muscular endurance and reduce the risk of injury. When progressing both OKC and CKC exercises athletes should work up to 2 to 3 sets of 15 to 20 reps with proper form without pain. When able to complete up to 60 repetitions in total, a progression in load and/or activity is indicated.
Neuromuscular Dynamic Stability Exercises
- •
See preceding Sensorimotor Exercises section.
Functional Exercises
- •
Gait training as needed to ensure proper gait mechanics without assistive device(s). Once able to fully weight bear without crutches without residual pain and/or effusion, a walking program can commence.
Milestones for Progression to the Next Phase
- •
Full flexion and extension ROM
- •
Full weight bearing with all activities
- •
No knee joint line tenderness
- •
Minimal to no knee pain with moderate activities
- •
No knee joint effusion following progressively more challenging activities of daily living and/or therapeutic activities
- •
Adequate strength
- •
Hamstrings within 20% of contralateral extremity (as measured either via a comparison between isometric hand-held dynamometry and/or isokinetic dynamometry)
- •
Quadriceps within 30% of contralateral extremity (as measured either via a comparison between isometric hand-held dynamometry and/or isokinetic dynamometry)
- •
- •
Balance testing within 30% of contralateral extremity (as measured by assessing differences between single leg stance time and the Star Excursion Balance Test)
- •
Able to bike for 30 minutes or longer
Phase III (weeks 8 to 12)
Protection
- •
Most patients with a large lesion on a weight-bearing surface with uncorrected abnormal alignments and/or meniscus injury may benefit from an unloader osteoarthritic brace to unload the involved compartment. If an athlete has poor dynamic foot posture (i.e., excessive pronation in stance phase), the use of foot orthotics may be indicated in order to minimize the applied load across the articular cartilage of the knee. It is also recommended that athletes begin their low-impact activities with well-cushioned shoes and work out on softer surfaces in order to acclimate to returning to activities that produce normal to high ground reaction forces.
Management of Pain and Swelling
- •
At this stage of rehabilitation pain/effusion should not be an issue. The athlete may have some transient pain/minor effusion following a newly progressed activity. If so the use of Cryotherapy (continuous cool system or ice packs), elevation, and high-voltage electrical stimulation can be used following exercise to assist with pain/effusion reduction.
Techniques for Progressive Increase in Range of Motion
Manual Therapy Techniques
- •
At this stage of rehabilitation ROM deficits should not be an issue. If the athlete is prone to joint and/or soft tissue tightness, provide instruction in periodic self-mobilization of the patellofemoral, tibiofemoral, and tibiofibular joints prophylactically.
Soft Tissue Techniques
- •
At this stage of rehabilitation soft tissue deficits should not be an issue. If the athlete is prone to joint and/or soft tissue tightness, instruction in periodic self-massage/soft tissue techniques prophylactically is warranted.
Stretching and Flexibility Techniques for the Musculotendinous Unit
- •
At this stage of rehabilitation the muscle length/integrity should be normal, and general flexibility exercises performed by the athlete to maintain normal length of the musculotendinous unit prior to and following exercise are:
- •
Hamstrings
- •
Gastrocnemius / soleus
- •
Hip abductors/ adductors
- •
Hip flexors
- •
Quadriceps
- •
Other Therapeutic Exercises
- •
During phase III of rehabilitation the injured athlete should continue to actively participate in core stability strengthening, typical upper body strengthening routine, and a cardiovascular conditioning program. Upright and/or recumbent exercise biking and a progressed walking program on either a treadmill, elliptical trainer, or outdoors on stable ground should be tolerated well.
Activation of Primary Muscles Involved
- •
At this stage of rehabilitation a continued balanced strengthening approach is needed to restore appropriate lower extremity function. A gradually progressed program of trunk, hip, and ankle exercises is recommended to control normal lower extremity forces and excessive forces through the injured knee.
Sensorimotor Exercises
- •
All the following therapeutic activities should be progressed in terms of difficulty (i.e., repetitions, time, intensity, etc.).
- •
Weight-shifting side to side drills
- •
Weight-shifting forward and backward drills
- •
Weight-shifting diagonal drills
- •
Bilateral minisquats; limit 0° to 45°
- •
Bilateral minisquats on an unstable surface (wobble board, tilt board, air disc, etc.); limit 0° to 45° ( Figure 31-18 )
FIGURE 31-18
Minisquats on an unstable wobble board. The athlete is instructed to perform the minisquat while minimizing wobble board movement.
- •
Balance activities onto and off from various unstable surfaces
- •
Perturbation drills
- •
Open and Closed Kinetic Chain Exercises
- •
OKC exercises
- •
4-way straight leg raises for an exercise warmup
- •
Supine
- •
Side lying for abductors
- •
Side lying for adductors
- •
Prone
- •
- •
LAQ
- •
Stationary bike with gradually progressed resistance and time
- •
Can begin swimming program
- •
- •
CKC exercises:
- •
Leg press (allows for graded weight bearing through the knee) in advance of doing minisquats; limit 0° to 90°
- •
Bilateral squats; limit 0° to 60°
- •
Lunges
- •
Step-ups
- •
Step-downs
- •
Progressed walking program (treadmill, elliptical trainer, or outdoors) in terms of distance, cadence, incline, etc.
- •
Can begin use of Stairmaster
- •
Wall sits
- •
Standing hip strengthening (abduction/adduction) with either resistive bands or circuit training equipment
- •
Techniques to Increase Muscle Strength, Power, and Endurance
- •
To continue to enhance the overall muscular function of the hip and knee musculature it is advisable to work with a high-repetition low load to enhance muscular endurance and reduce the risk of injury. When progressing both OKC and CKC exercises, athletes should work up to 2 to 3 sets of 15 to 20 reps with proper form without pain. When able to complete up to 60 repetitions in total, a progression in load and/or activity is indicated.
Neuromuscular Dynamic Stability Exercises
- •
See preceding Sensorimotor Exercises section.
Functional Exercises
- •
As long as the athlete is tolerating the previously started walking program, this walking program should be advanced in terms of time, distance, intensity, and terrain as tolerated.
Sport-Specific Exercises
- •
Agility and sport specific activities can commence at this stage of rehabilitation as long as clinically the athlete’s knee is progressing as expected and that pain and effusion are under control. Such activities should be sport specific and initiated at about 50% effort and progressed to full effort into phase IV of rehabilitation as tolerated. Initiate to full effort only when such activities do not induce recurrent or persistent pain or effusion.
Milestones for Progression to the Next Phase
- •
Full nonpainful ROM
- •
No knee joint effusion following progressively more challenging activities of daily living and/or therapeutic activities
- •
Adequate strength
- •
Hamstrings within 10% of contralateral extremity (as measured either via a comparison between isometric hand-held dynamometry and/or isokinetic dynamometry)
- •
Quadriceps within 10% of contralateral extremity (as measured either via a comparison between isometric hand-held dynamometry and/or isokinetic dynamometry)
- •
- •
Balance testing within 20% of contralateral extremity (as measured by assessing differences between single leg stance time and the Star Excursion Balance Test)
- •
Able to walk for 1 hour or longer
Phase IV (weeks 12+)
Protection
- •
Continued use of unloader osteoarthritic brace to unload the involved compartment and foot orthotics if previously recommended, minimizing the applied load across the articular cartilage of the knee
Management of Pain and Swelling
- •
At this stage of rehabilitation pain/effusion should not be an issue. The athlete may have some transient pain/minor effusion following a newly progressed activity. If so the use of Cryotherapy (continuous cool system or ice packs), elevation, and high-voltage electrical stimulation can be used following exercise to assist with pain/effusion reduction.
Techniques for Progressive Increase in Range of Motion
Manual Therapy Techniques
- •
At this stage of rehabilitation ROM deficits should not be an issue. If the athlete is prone to joint and/or soft tissue tightness, provide instruction in periodic self-mobilization of the patella femoral, tibiofemoral, and tibiofibular joints prophylactically.
Soft Tissue Techniques
- •
At this stage of rehabilitation soft tissue deficits should not be an issue. If the athlete is prone to joint and/or soft tissue tightness, instruction in periodic self-massage/soft tissue techniques prophylactically is warranted.
Stretching and Flexibility Techniques for the Musculotendinous Unit
- •
At this stage of rehabilitation the muscle length/integrity should be normal, and general flexibility exercises performed by the athlete to maintain normal length of the musculotendinous unit prior to and following exercise are:
- •
Hamstrings
- •
Gastrocnemius / soleus
- •
Hip abductors/ adductors
- •
Hip flexors
- •
Quadriceps
- •
Other Therapeutic Exercises
- •
During phase IV of rehabilitation the injured athlete should continue to actively participate in core stability strengthening, typical upper body strengthening routine, and a cardiovascular conditioning program. Upright and/or recumbent exercise biking and a progressed jogging program on either a treadmill, elliptical trainer, or outdoors on stable ground should be tolerated well.
Activation of Primary Muscles Involved
- •
At this stage of rehabilitation a continued balanced strengthening approach is needed to restore appropriate lower extremity function. A gradually progressed program of trunk, hip, and ankle exercises is recommended to control normal lower extremity forces and excess forces through the injured knee.
Sensorimotor Exercises
- •
Progressed weight-shifting side to side drills
- •
Progressed weight-shifting forward and backward drills
- •
Progressed weight-shifting diagonal drills
- •
Bilateral minisquats; no range of motion limit as long as asymptomatic
- •
Bilateral minisquats on an unstable surface (wobble board, tilt board, air disc, etc.); no range of motion limit as long as asymptomatic
- •
Progressed balance activities onto and off from various unstable surfaces
- •
Perturbation drills
Open and Closed Kinetic Chain Exercises
- •
OKC exercises
- •
4-way straight leg raises for an exercise warmup
- •
Supine
- •
Side lying for abductors
- •
Side lying for adductors
- •
Prone
- •
- •
LAQ
- •
Stationary bike with progressed resistance and time
- •
Swimming program
- •
- •
CKC exercises
- •
Progressed leg press from bilateral press to unilateral press as tolerated (allows for graded weight-bearing through the knee)
- •
Bilateral squats; typically would limit 0° to 80°, but this range of motion should be adjusted based on the location of the lesion.
- •
Lunges
- •
Step-ups
- •
Step-downs
- •
Progressed running program (treadmill, elliptical trainer, or outdoors) in terms of distance, cadence, incline, etc.
- •
Standing hip strengthening (abduction/adduction) with either resistive bands or circuit training equipment
- •
Techniques to Increase Muscle Strength, Power, and Endurance
- •
To continue to enhance the overall muscular function of the hip and knee musculature, it is advisable to work with a high-repetition low load to enhance muscular endurance and reduce the risk of injury. When progressing both OKC and CKC exercises athletes should work up to two to three sets of 15 to 20 reps with proper form without pain. When able to complete up to 60 repetitions in total then a progression in load and/or activity is indicated.
Neuromuscular Dynamic Stability Exercises
- •
See preceding Sensorimotor Exercises section.
Plyometrics
- •
Plyometrics should be started with slow, controlled movements and then progressed to more explosive type activities. The rationale behind a plyometric program is to train the musculature, connective tissue, and nervous system to perform through cycles of stretch-shortening with proper technique and mechanics. It has been shown that modifiable knee injury risk factors of decreased landing forces, decreased varus/valgus moments, and enhanced muscle activation have resulted from plyometrics, dynamic balance and strengthening programs, stretching, body awareness and decision-making drills, and core stabilization drills.
Functional Exercises
- •
As long as the athlete is tolerating the progression from a walking program to a jogging/running program, this program should be advanced in terms of time, distance, intensity, and terrain as tolerated ( Box 31-1 ).
Box 31-1
Return to Running Program *
* When beginning a return to running program a runner and therapist should take into consideration the original injury/underlying health status in order to modify this program accordingly. A runner should progress through this program one phase at a time.
Phase I: Walking Program
Patient should be able to walk, pain free, aggressively (roughly 4.2 to 5.2 miles per hour), in a controlled environment, preferably on a treadmill, before beginning the plyometric and walk/jog program.
Phase II: Plyometric Routine
A mile run typically consists of 1500 foot contacts, 750 per foot. This program integrates 470 foot contacts per leg, which would be equivalent to two thirds of the foot contacts during a mile run. Successful completion of this phase is a good indicator that an athlete is ready to attempt running a half to three-quarters of a mile distance.
EXERCISE
SETS
FOOT CONTACTS PER SET
TOTAL FOOT CONTACTS
Two-leg ankle hops: in place
3
30
90
Two-leg ankle hops: forward/backward
3
30
90
Two-leg ankle hops: side to side
3
30
90
One-leg ankle hops: in place
3
20
60
One-leg ankle hops: forward/backward
3
20
60
One-leg ankle hops: side to side
3
20
60
One-leg leg broad hop
4
5
20
22
470
Rest Intervals:
Between Sets:
90 seconds
Between Exercises:
3 minutes
General Guidelines
- •
Stretch Gastro, Soleus, Quads and Hamstrings between exercises.
- •
If a patient experiences pain or is unable to complete an exercise, stop, stretch, and apply ice to the involved area. Patient should be pain free the next day; attempt to restart the routine.
Phase III: Walk/Jog Progression
Patient should begin this program on level ground if:
- 1.
Successfully completed Phase I and II
- 2.
Does not have pain with normal daily activities
WALK
JOG
REPETITIONS
TOTAL TIME
Stage I
5 minutes
1 minute
5 times
30 minutes
Stage II
4 minutes
2 minutes
5 times
30 minutes
Stage III
3 minutes
3 minutes
5 times
30 minutes
Stage IV
2 minutes
4 minutes
5 times
30 minutes
Stage V
Jog every other day with a goal of reaching 30 consecutive minutes; begin with 5 minutes of walking, gradually increasing the pace. End with 5 minutes of walking, gradually decreasing the pace to a comfortable walk.
- •
Sport-Specific Exercises
- •
The overall timing of return to full preinjury athletic activity is dependent upon the athlete, lesion type and location, other comorbidities, and the specific sports-related activities that the athlete needs to be able to achieve. During phase IV of rehabilitation the athlete should be in a position to begin sport-specific practices, first at 50% effort level and then progressed at no faster than a 10% incremental intensity per week until back to full intensity.
Milestones for Progression to Advanced Sport-Specific Training and Conditioning
- •
Full nonpainful ROM
- •
No knee joint effusion following progressively more challenging sport-specific drills and training
- •
Adequate strength
- •
Hamstrings within 5% of contralateral extremity (as measured either via a comparison between isometric hand-held dynamometry and/or isokinetic dynamometry)
- •
Quadriceps within 5% of contralateral extremity (as measured either via a comparison between isometric hand-held dynamometry and/or isokinetic dynamometry)
- •
- •
Balance testing within 10% of contralateral extremity (as measured by assessing differences between single leg stance time and the Star Excursion Balance Test)
- •
Able to complete full sport-specific workouts two to three times per week without recurrent pain and knee joint effusion
Performance Enhancement and Beyond Rehabilitation: Training/Trainer and Optimization of Athletic Performance
- •
Once an athlete has achieved the above milestones and has returned to athletic activity following conservative treatment of an articular cartilage lesion of the knee, it is advisable to continue a generalized core and lower extremity strengthening program. Such a program will ensure maximal muscular function to minimize stress through the knee joint.
- •
The continued use of the unloader brace and orthotics (if prescribed) are advised to assist in minimizing applied forces across the knee joint.
Specific Criteria for Return to Sports Participation: Tests and Measurements
- •
Before discussion of return to sports activity following conservative management of the athlete with an articular cartilage lesion, it is important for the clinician to know that, generally, the return to sport rate for those having undergone a surgical repair for an articular cartilage lesion is 73%.
- •
It has also been shown that those with a smaller lesion, shorter duration of symptoms, less invasive surgical procedure, and fewer prior surgical procedures have a higher return to sports rate.
- •
Currently there is no literature that reports return to sports following conservative management of the athlete with an articular cartilage lesion. One could predict based on the surgical literature that the younger athlete with the smaller lesion that is on a joint surface that withstands less weight-bearing forces will be more successful in returning to her/his previous sports activity.
- •
Specific criteria
- •
Full nonpainful ROM
- •
No knee joint effusion following progressively more challenging sport specific drills, training, and scrimmages
- •
Adequate strength maintained after beginning sports specific training
- •
Hamstrings within 5% of contralateral extremity (as measured either via a comparison between isometric hand-held dynamometry and/or isokinetic dynamometry)
- •
Quadriceps within 5% of contralateral extremity (as measured either via a comparison between isometric hand-held dynamometry and/or isokinetic dynamometry)
- •
Able to complete full sport-specific workouts three to four times per week without recurrent pain and knee joint effusion
- •
Evidence
Multiple-Choice Questions
- QUESTION 1.
Which of the following are considered key factors to consider when devising a nonsurgical rehabilitation program for a patient who has had an articular cartilage injury?
- A.
Minimize pain and joint effusion
- B.
Restore muscle function
- C.
Enhance proprioception and neuromuscular control
- D.
All the above
- A.
- QUESTION 2.
What type of joint forces should be avoided while performing exercises during the early phases of rehabilitation following articular cartilage injury?
- A.
Shear forces
- B.
Distraction forces
- C.
Compressive forces
- D.
A and C
- A.
- QUESTION 3.
Which muscle group should one be cautious with when stretching during the early phases of rehabilitation following articular cartilage injury?
- A.
Hamstrings
- B.
Hip abductors
- C.
Quadriceps
- D.
Gastrocnemius/Soleus
- A.
- QUESTION 4.
What type of knee brace may a patient with an articular cartilage lesion need during the later stages of rehabilitation and return to sports to unload a specific compartment of the knee?
- A.
Drop-lock rehabilitative brace
- B.
Compression sleeve
- C.
Neoprene hinged brace
- D.
Unloader OA brace
- A.
- QUESTION 5.
What signs and symptoms let the clinician know that the athlete is not tolerating a given activity level during the course of rehabilitation?
- A.
Recurrent effusion
- B.
Joint line tenderness
- C.
Residual pain leading to a limp with ambulation
- D.
All the above
- A.
Answer Key
- QUESTION 1.
Correct answer: D (see Introduction )
- QUESTION 2.
Correct answer: D (see Phase I )
- QUESTION 3.
Correct answer: C (see Phase I )
- QUESTION 4.
Correct answer: D (see Phase III )
- QUESTION 5.
Correct answer: D (see throughout all phases)
Postoperative Rehabilitation after Femoral Condyle or Trochlear Groove Microfracture
- Luke T. O’Brien, PT, SCS, PES
- J. Richard Steadman, MD
Indications for Surgical Treatment
- •
Full-thickness defect (grade IV)
- •
Unstable full-thickness lesion
- •
Degenerative joint disease lesion
- •
Requires proper knee alignment
Brief Summary of Surgical Treatment
- •
Correct joint environment at time of surgery
- •
Rough shave to remove cartilage remnants
- •
Curettes to remove calcified cartilage layer
- •
Surgical awls—penetrate subchondral bone
- •
Perforations 3 to 4 mm apart
- •
Don’t “connect the dots”
- •
Maintain subchondral plate integrity
- •
Formation of “super clot”
Before Surgery: Overview of Goals, Milestones, and Guidelines 1
1 Prehabilitation, if appropriate, is described in the Nonoperative Rehabilitation section of this chapter.
- •
Must have proper patient selection
- •
Patient understands postoperative process.
- •
Patient will have to undergo strict rehabilitation program.
- •
- •
Must have proper alignment
- •
Must use proper technique
- •
Must improve joint environment
- •
Proper rehabilitation
Phase I (days 0 to 14): Immediate Postoperative Period
- •
Patella mobility is the key to the knee.
- •
A frequent complication of knee surgery is the formation of restrictive scar.
- •
Mobilization of the patella as well as the quadriceps and patellar tendon helps to maintain the integrity of the anterior interval and the suprapatellar pouch.
- •
Restrictive scar formation and the subsequent loss of these joint “spaces” increases not only patellofemoral joint contact pressure, but also tibiofemoral contact pressure.
Goals
- •
Protect the microfracture.
- •
Begin restoring tibiofemoral and patellofemoral range of motion.
- •
Reduce postoperative pain, swelling, and inflammation.
- •
Minimize the effects of immobilization/non–weight-bearing.
Protection
- •
All trochlear groove microfractures are braced in an immobilizer for 8 weeks. This is done to ensure that the median ridge of the patella does not engage the trochlea. The immobilizer is used at all times, including during sleep, unless in continuous passive motion (CPM).
- •
No brace is used for femoral condyle/tibial plateau lesions.
- •
Femoral condyle and tibial plateau microfractures mobilize with touch toe weight bearing for 8 weeks.
- •
Trochlear groove microfractures mobilize with partial weight bearing for 2 weeks.
- •
CPM (0° to 50°) is used 8 hours per day for 8 weeks. This improves the quality of the repair tissue, as well as ensuring congruency of the microfracture with the surrounding articular cartilage.
Management of Pain and Swelling
- •
Femoral nerve block for 24 hours postoperatively
- •
Oral pain medication
- •
Continuous cryotherapy for pain and inflammation reduction
- •
Early range of motion exercises to facilitate resorption of swelling exudate
Techniques for Progressive Increase in Range of Motion
Range of Motion Restrictions
- •
Typically FROM for femoral condyle/tibial plateau
- •
May have ROM restrictions for trochlear groove, depending upon the size of the lesion
Manual Therapy Techniques
- •
Patella mobilization—medial/lateral mobilization of the patella, as well as the patella and quadriceps tendons. Superior/inferior mobilization of the patella. This helps limit scarring of the anterior interval and suprapatellar pouch, and the resultant increase in joint contact pressure.
- •
Posterior tibial mobilizations in extension to ensure that symmetrical knee extension is attained.
- •
PROM—seated off the end of the bed with physical therapist assistance for initial flexion ROM. This is a particularly helpful position for trochlear groove microfractures with range of motion restriction or the presence of a femoral nerve block. Progress to independent wall slide as tolerated.
- •
Anterior-posterior tibial mobilization to ensure symmetrical extension.
Soft Tissue Techniques
- •
Lymphatic drainage techniques for swelling as required
Stretching and Flexibility Techniques for the Musculotendinous Unit
- •
Sit and reach stretch with strap around foot. Done to maintain ankle dorsiflexion while patient has a protected weight-bearing status
Other Therapeutic Exercises
- •
Well-leg biking/rowing and or arm bike for maintenance of cardiovascular fitness
Activation of Primary Muscles Involved in Injury Area or Surgical Structures
- •
Quadriceps sets. There are three benefits of teaching an isolated quad set in which the patella glides superiorly and the knee moves into terminal extension.
- •
First, it resists muscle atrophy.
- •
Second, it reinforces full knee extension, eliminating the possibility of developing a flexion contracture.
- •
Finally, a quad set that locks the joint in terminal extension opens the anterior interval by 1 cm, and by doing so reduces the risk of anterior interval scarring.
- •
- •
Hamstring sets. Usually performed as an isometric straight leg pulldown, or a straight leg bridge on a stable surface
- •
Gluteal isometrics
- •
Calf pumps for prevention of blood clots
Milestones for Progression to the Next Phase
- •
Approximately 115° of knee flexion to allow for a revolution on a stationary bike
Phase II (weeks 2 to 8 postoperative)
- •
Regaining symmetrical knee extension is essential to the normal functioning of the knee.
- •
It allows weight-bearing force to be distributed over the entire available chondral surface, decreasing potential point loading.
- •
Full knee extension also allows the quadriceps to fire in inner range, which is essential for full muscular development.
Goals
- •
Protect the microfracture.
- •
Restore full tibiofemoral and patellofemoral joint range of motion.
- •
Eliminate swelling and inflammation.
- •
Minimize the effects of immobilization/non–weight-bearing.
Protection
- •
Continue touch toe weight-bearing status for femoral condyle microfractures. Trochlear groove microfractures begin to wean off crutches over a period of 10 days after 2 weeks.
- •
Immobilizer use is continued for trochlear groove cases.
- •
CPM is continued 8 hours/day through 8 weeks.
Management of Pain and Swelling
- •
Pain medication use is typically ceased during this time.
- •
Cryotherapy three to four times daily for 20 minutes duration for pain and inflammation reduction
- •
Range of motion exercises
Techniques for Progressive Increase in Range of Motion
Manual Therapy Techniques
- •
Patella mobilization and posterior tibial mobilization are continued.
- •
PROM—Patients are encouraged to gently add overpressure to wall slides by placing their well leg on top of the surgical leg. Flexion on a Swiss ball is also added, with the PT gently applying overpressure at the end of range. All overpressure techniques should work into joint stiffness, but never reproduce joint pain.
- •
Stationary bike is introduced to facilitate ROM gains. Patients begin with 10 minutes duration and increase periodically to achieve 30 minutes duration by 8 weeks. All biking is done with no resistance through 8 weeks.
Soft Tissue Techniques
- •
Lymphatic drainage techniques for swelling as required.
- •
Trigger point release of hip flexor/tensor fascia lata is occasionally necessary owing to extended time in CPM and/or ambulating in an immobilizer.
Stretching and Flexibility Techniques for the Musculotendinous Unit
- •
Sit and reach stretch with strap around foot
Other Therapeutic Exercises
- •
Well-leg biking/rowing and or arm bike for maintenance of cardiovascular fitness
- •
Deep water aquajogging, ensuring that feet do not touch the bottom of the pool
- •
Upper body resistance training while ensuring adherence to weight-bearing and ROM precautions
Activation of Primary Muscles Involved in Injury Area or Surgical Structures
- •
Quadriceps, hamstrings, and gluteal isometrics are continued and hold times progressed.
- •
Biofeedback may be used during quadriceps isometrics to facilitate a minimum level of performance during endurance holds for time.
- •
Straight leg raises are only introduced when the patient is able to demonstrate a quad set that locks the knee in end of range extension. Performing a straight leg raise in the presence of a quadriceps lag places a trochlear groove microfracture under unnecessary stress.
Milestones for Progression to the Next Phase
- •
8 weeks post surgery. This ensures sufficient time has passed for the microfracture to tolerate weight-bearing stress.
- •
Full passive range of motion
- •
Quad set that locks the knee in terminal extension
Phase III (weeks 9 to 12 postoperative)
Related posts:
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
