For acute injuries, ice should be applied to decrease pain and swelling, blood flow, and muscle spasm. It is the agent of choice for nearly all acute injuries and even overuse injuries.

Heat is employed less commonly; it reduces pain and spasm and increases blood flow and soft-tissue relaxation. It has a limited role in acute injuries or overuse syndromes when swelling and inflammation are present.

Once swelling and muscle spasm subside, therapeutic exercise is initiated to improve joint range of motion and to stretch and strengthen muscles.

Joint mobilization is best accomplished by active mobilization in which the athlete moves the injured joint. Passive mobilization utilizes another individual, usually a therapist, to move the patient’s contracted joint. This technique is often complicated by exacerbation of the injury, tearing or stretching of soft tissues, and hemorrhage and should only be done by an experienced therapist when active mobilization has failed (7, 8 and 9).

Active-assist mobilization is a combination of the two methods and has limited indications in the young athlete.

Stretching techniques are designed to restore flexibility after an injury. Static stretching employs techniques in which the involved or target muscle is stretched or maintained for approximately 20 seconds. It is safer than ballistic stretching in which sudden bounces or joint motions are permitted. Ballistic stretching can cause activation of the stretch reflex and cause muscle-tendinous strain and is not recommended after acute injuries.

Strengthening is an important part of the rehabilitation program and includes isometric, isotonic, isokinetic, concentric and eccentric, closed kinetic chain, and functional exercises.

Electrogalvanic stimulation causes small muscle contractions that may reduce swelling and muscle atrophy (7, 8 and 9).

Transcutaneous nerve stimulation employs electrical stimulation to block pain impulses from the site of injury or site of surgery (7, 8 and 9).

There is no objective evidence of the benefits of these two modalities in the treatment of athletic injuries in the child (7, 8 and 9). Most sports injuries in the skeletally immature are amenable to nonoperative management. Not all injuries require supervised rehabilitation, but it has been shown to lessen recovery time and decrease reinjury rates.

Children with recurrent patellar instability have one or several features which predispose to the recurrence. Anatomic factors include an increased Q angle, increased femoral tibial valgus, excessive external tibial torsion, femoral condylar dysplasia, patella alta, and generalized ligamentous laxity (23, 24 and 25, 35, 45, 46 and 47). The Q angle is the angle formed by a long axis drawn along the quadriceps mechanism from the anterior superior iliac spine (ASIS) to the midaxis of the knee joint subtended by a long axis drawn along the patellar tendon. A normal Q angle is 10 degrees or less (Fig. 31-3A-C). Children with recurrent patellar instability exhibit a positive apprehension test. Apprehension is produced when an attempt is made to displace the patella laterally with the knee flexed approximately 30 degrees.

Surgery is indicated when a patient has had three or four recurrences of patellar dislocation and the instability affects his or her lifestyle. Correction of the anatomic variants is crucial for the long-term outcome.

Surgery may entail soft-tissue surgery around the patella, including lateral retinacular release, reconstruction of the MPFL, vastus medialis advancement with medial reefing, Insall’s proximal patellar realignment, or semitendinosus tenodesis.

Lateral retinacular release alone for patellar instability is rarely indicated. There are isolated reports of its success in the treatment of recurrent patellar dislocation, but its exact role in this condition remains to be determined (48, 49). Excessive lateral retinacular release combined with aggressive medial reefing may result in iatrogenic medial subluxation and must be avoided (29, 50, 51). Lateral retinacular release usually must be combined with reconstruction of the MPFL or by vastus medialis advancement.

Reconstruction of the MPFL has become popular in acute or early recurrent dislocation of the patella (29, 35). The MPFL may be reconstructed in several ways including free hamstring graft (semitendinosus tendon) (29) or by the use of an autologous quadriceps tendon (52) (Fig. 31-4A-E). It can be routed through drill holes in the patella and fixed to its normal origin at the adductor tubercle or fixed in a similar fashion using suture anchors.

In the case of the autologous quadriceps tendon, an 8 mm width × 60 mm length medial quadriceps tendon graft is harvested, pressed beneath the medial patellar retinaculum, and sutured to the intermuscular septum at the adductor tubercle. The graft is sutured in place with the knee in 30 degrees of flexion.

Thus drill holes are avoided, allowing the procedure to be performed in skeletally immature individuals. As a variation, the graft may be fixed to the femur at the same location using a suture anchor. In the situation of more chronic recurrent dislocations, a vastus medialis obliquus (VMO) advancement distally and laterally with medial reefing is performed in addition to the MPFL reconstruction (53, 54 and 55).

With subluxation or dislocation of the patella in skeletally immature patients, the open growth plate of the tibial tubercle, which prohibits operations that transfer the origin of the patellar tendon, limits the surgeon’s options. For the growing child with recurrent subluxation or dislocation of the patella—whether owing to malalignment, trauma, or mild ligamentous laxity (e.g., that seen in Down syndrome)—the proximal soft-tissue realignment described by Insall and colleagues (55, 56) provides a method of realigning the forces on the patella. For us, this method is preferable to detaching and then advancing the vastus medialis muscle. In cases in which advancement of the medialis muscle seems necessary, the muscle is usually so deficient that little is gained, and it is difficult to secure the muscle in place. The proximal realignment provides a secure repair with little tension on the suture lines and therefore earlier rehabilitation.

In cases of congenital dislocation associated with deficiency of the lateral femoral condyle or muscle structure, however, this operation is usually not sufficient. This is also true for children with Down syndrome or other collagen disorders who have severe ligamentous laxity and poor tissue for repair. In such cases, we prefer to combine elements of this procedure with the semitendinosus tenodesis of the patella.

The use of the semitendinosus tenodesis was first described by Galeazzi in 1922 (57, 58). The semitendinosus tenodesis procedure addresses several
problems that the orthopaedic surgeon often encounters in the child with recurrent dislocation of the patella: ligamentous laxity, deficient lateral condyle, deficient medial musculature, and open growth plates. In all of the conditions in which recurrent dislocation of the patella is encountered (e.g., Down syndrome, congenital dislocating patella), the semitendinosus tendon is usually normal. We have found this procedure, often in combination with a proximal realignment, to be an excellent solution to the unusual problem of recurrent dislocating patella in skeletally immature children.

Reconstruction of the MPFL (Fig. 31-4)

Semitendinosus Tenodesis of Patella for Recurrent Dislocation (Figs. 31-9, 31-10, 31-11, 31-12, 31-13 and 31-14)

This graft reproduces the vector of the patellotibial ligament. It can also be employed when there is persistent instability after already performing a lateral release and MPFL reconstruction or VMO advancement (Fig. 31-15).

If there is an excessive Q angle, distal realignment is advocated as well. If the individual is a skeletally mature youth, the tibial tubercle is osteotomized and shifted medially without distal transfer (Elmslie-Trillat procedure) (59) (Fig. 31-16A,B). A modification of the Elmslie-Trillat procedure is the Fulkerson procedure (60), in which a more generous osteotomy of the anterior tibial tubercle is performed and the tubercle transferred anteriorly and medially (Fig. 32-16C). This procedure is primarily reserved for patellofemoral pain in adults and is not recommended for instability in adolescents or young adults.

In the immature child with an excessive Q angle and open tibial tubercle apophysis, osteotomy is contraindicated because of the potential for growth arrest and genu recurvatum. In these cases, the patellar tendon may be split and the lateral half delivered beneath the medial portion of the patellar tendon and sutured to the periosteum of the proximal tibia medially by direct suture or by suture anchors (61) (Fig. 31-17). Acceptable results can be expected in up to 90% of cases employing the Roux-Goldthwait procedure.

Semitendinosus Tenodesis of Patella for Recurrent Dislocation: The Galeazzi Procedure (Figs. 31-15 and 31-16)

An option is to sharply dissect the entire patellar tendon from its insertion using a scalpel and to resuture it more medially to restore a normal Q angle (62). Care must be taken not to move the insertion too distally, which may lead to patella baja and significant pain.

Rehabilitation following a patellar stabilization procedure is very important. It is crucial to move the knee early, and immobilization in a removable knee immobilizer for 3 to 4 weeks is sufficient for healing. Active range of motion and strengthening are essential parts of the rehabilitation program, and a resumption of sports activity can be anticipated in 4 to 6 months.

The avulsion fracture of the tibial intercondylar eminence usually occurs in individuals between the ages of 8 to 14 with no predilection for gender. This is still a relatively rare injury accounting for about 2% of knee injuries or 3 per 100,000 children per year (101, 102). Classically, pediatric tibial spine fractures occurred from bicycling accidents, although they are also seen with pedestrian-motor vehicle accidents or sports injuries (103, 104 and 105). Although far less common, tibial spine fracture can occur in adults and frequently involve lesions of the meniscus, capsule, or collateral ligaments because they are associated with higher energy mechanisms (106, 107, 108, 109, 110 and 111).

Fractures of the tibial spine are avulsion fractures of the ACL insertion and, in addition to disrupting ACL continuity, may, depending on the size of the fracture, involve the articular surface of the tibia (112, 113). Noyes has shown that as the subchondral bone fails, a elongation or stretch of the ACL occurs (112). This has led many authors to equate this injury to the midsubstance ACL rupture in adults (104, 105, 114, 115, 116, 117, 118, 119 and 120).

Historically, treatment has evolved from closed treatment of all fractures to operative treatment of certain types. Garcia and Neer (121) reported 42 fractures of the tibial spine in patients ranging in age from 7 to 60 years with successful closed management in half their patients. Meyers and McKeever (103), recommended arthrotomy and open reduction for all displaced fractures, followed by cast immobilization with the
knee in 20 degrees of flexion. Gronkvist et al. (117) reported late instability in 16 of 32 children with tibial spine fractures and recommended surgery for all displaced tibial spine fractures particularly in children over 10 years of age because of increased demand on the ACL-tibial spine complex. In a comparison of displaced tibial spine fractures, McLennan (122) reported on 10 patients treated with either closed reduction or arthroscopic reduction with or without internal fixation. After a second-look arthroscopy at 6 years, those treated with closed reduction had more knee laxity than those treated arthroscopically.

Modern treatment is based on fracture type. Fractures that are able to be reduced can be treated closed. Hinged and displaced fractures that do not reduce require open or arthroscopic reduction with internal fixation. A variety of treatment options have been reported, with the goal of obtaining a stable, painfree knee. The prognosis for closed treatment of nondisplaced and reduced tibial spine fractures and for operative treatment of displaced fractures is good. Most series report healing with an excellent functional outcome despite some residual knee laxity (114, 115, 119, 120, 122, 123, 124, 125, 126, 127, 128 and 129). Potential complications include nonunion, malunion, arthrofibrosis, residual knee laxity, and growth disturbance (114, 115, 119, 120, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132 and 133).

The most common mechanism of tibial eminence fracture in children has been a fall from a bicycle, but with increased participation in youth sports at earlier ages and higher competitive levels, fractures resulting from sporting activities are being seen with increased frequency. The differential injury patterns of an ACL tear versus a tibial eminence fracture in the skeletally immature knee may be due to loading conditions, biomechanical properties, and anatomical differences (112, 113, 119, 134). The most common mechanism of tibial eminence fracture is forced valgus and external rotation of the tibia, although tibial spine avulsion fractures can also occur from hyperflexion, hyperextension, or tibial internal rotation. Slower loading rates, relative weakness of the incompletely ossified intercondylar eminence compared to the ligament midsubstance, greater elasticity of the ACL, and a wider intercondylar notch are believed to preferentially result in tibial spine avulsion fracture (112, 113, 119, 134).

In a biomechanical cadaver study, a fracture of the anterior tibial eminence was simulated by an oblique osteotomy beneath the eminence and traction on the ACL. In each specimen, the displaced fragment could be reduced into its bed by extension of the knee, likely affected by the lateral femoral condyle (135). In experimental models, midsubstance ACL injuries tend to occur under rapid loading rates, whereas tibial eminence avulsion fractures tend to occur under slower loading rates (112).

Additionally, intercondylar notch morphology may also influence injury patterns. In a retrospective study of 25 skeletally immature patients with tibial spine fractures compared to midsubstance ACL injuries, Kocher et al. (134) found narrower intercondylar notches in those patients sustaining midsubstance ACL injuries.

As with patients with fractures around the knee joint, tibial spine fractures present with a painful swollen knee (hemarthrosis), limitation of knee motion, and difficulty with weight bearing. Evaluation should consist of a thorough history and physical examination. Sagittal plane laxity is often present, but the contralateral knee should be assessed for physiologic laxity. However, pain may make a thorough examination of the ligaments difficult. If possible, gentle stress testing should be performed to detect any tear of the MCL or LCL. Patients with a late malunion of a displaced tibial spine fracture may lack full extension because of a bony block. Patients with a late nonunion of a displaced tibial spine fracture may have increased knee laxity, a positive Lachman examination, and pivot-shift examination. A complete neurological and vascular examination should be performed.

Standard roentgenograms and anteroposterior, lateral, and notch radiographic views are usually diagnostic. The fracture is best seen on the lateral and notch views (Fig. 31-22A,B). Radiographs should be carefully scrutinized as the avulsed fragment may be mostly nonossified cartilage with only a small, thin ossified portion visible on the lateral view. If necessary, computed tomographic (CT) scanning allows refined definition of the fracture anatomy.

MRI is not typically needed in the diagnosis and management of tibial eminence fractures in children. MRI may be helpful to confirm the diagnosis in cases with a very thin ossified portion of the avulsed fragment and to evaluate associated collateral ligament and chondral, meniscal, or physeal pathology; however these are uncommon. If distal pulses are abnormal or a dislocation is suspected, an arteriogram should be obtained.

Associated intra-articular injuries are relatively uncommon. Intercondylar eminence fractures may include or be associated with any combination of bone, chondral, meniscal, or ligamentous injuries (108). However, in a more recent series of 80 skeletally immature patients who underwent surgical fixation of tibial eminence fractures, Kocher et al. (136) found no associated chondral injuries
and associated meniscal tear in only 3.8% (3/80) of patients (Fig. 31-23). Associated collateral ligament injury or proximal ACL avulsion in conjunction with a tibial spine fracture has also been reported (137, 138).

The classification system of Meyers and McKeever (103, 139) is based on the degree of displacement and is widely used to classify fractures and to guide treatment (Fig. 31-24). Zaricznyj (140) later modified this classification to include a fourth type which are comminuted fractures of the tibial spine.

The interobserver reliability between type 1 and type 2/3 fractures is good; however differentiation between type 2 and 3 fractures may be difficult (134).

Between the condyles, the intercondylar eminence or spine is the insertion point for portions of the menisci and the anterior and posterior cruciate ligaments (PCLs). The tibial eminence is triangular and refers to the portion of the proximal tibia where there are two ridges of bone and cartilage. In the immature skeleton, the proximal surface of the eminence is covered entirely with cartilage. The ACL attaches distally to the anteromedial portion of the tibial intercondylar eminence (Fig. 31-25). The PCL inserts on the posterior aspect of the proximal tibia, distal to the joint line. Both menisci insert into the tibia in the region between the lateral and medial eminences, but there is no direct connection between the ACL and the menisci. In 12 patients with displaced tibial spine fractures that were unable to be reduced closed, Lowe et al. (141) reported that the anterior horn of the lateral meniscus and the ACL were attached simultaneously and pulling in different directions.

Meniscal or intermeniscal ligament entrapment under the displaced tibial eminence fragment can be common and may be a rationale for considering arthroscopic or open reduction in displaced tibial spine fractures (Fig. 31-26) (108, 136, 142, 143). Meniscal entrapment can prevent the anatomic reduction of the tibial spine fragment, which may result in increased anterior laxity or a block to extension and knee pain after the fracture has healed (104, 105, 117, 118, 122). Mah et al. (144) found medial meniscal entrapment preventing reduction in 8 of 10 children with type 3 fractures undergoing arthroscopic management. In a consecutive series of 80 patients who underwent surgical fixation of tibial eminence fractures which were not able to be reduced closed, Kocher et al. (136) found entrapment of the anterior horn medial meniscus (n = 36), intermeniscal ligament (n = 6), or anterior horn lateral meniscus (n = 1) in 26% of type 2 fractures and 65% of type 3
fractures. The entrapped meniscus can typically be extracted with an arthroscopic probe and retracted with a retaining suture (Fig. 31-27).

Current treatment options include cast immobilization (125, 127), closed reduction with immobilization (104, 120), open reduction with immobilization (127), open reduction with internal fixation (120, 128), arthroscopic reduction with immobilization (145), arthroscopic reduction with a variety of fixation methods, including: suture fixation (125, 130, 144, 146, 147 and 148), wire (149), screw fixation (115, 125, 145, 150), anchor fixation (151), and bioabsorbable nail fixation (148). Many options still persist regarding the fixation of the fracture and have all been used with good success; most commonly, suture or screw fixation is used. Recent studies are equivocal in terms of strength of fixation, although suture fixation may be favored since it has the advantages of eliminating the risks of comminution of the fracture fragment, posterior neurovascular injury, and the need for hardware removal (147, 148 and 149, 152).

The goal of treatment of a tibial spine avulsion is anatomic reduction; however, there is controversy regarding whether the tibial spine should be overreduced. Theoretically, overreduction may lead to excessive tightening of the ACL and limitation of knee motion (153). On the other hand, it is likely that permanent intersubstance stretching of the ACL occurs before the fracture (112), and therefore overreduction could be considered. Although further clinical or in vitro research is required, long-term evaluation of well-reduced tibial eminence fractures shows subtle increases in anteroposterior knee laxity without functional deficit (114, 117, 119, 124, 131, 141, 150).

Closed treatment is typically utilized for type 1 fractures and for type 2 or 3 fractures that are able to be successfully reduced closed. Aspiration of the hematoma is performed first and closed reduction is achieved by placement of the knee in full extension or 20 to 30 degrees of flexion. If the fracture fragment extends into the medial or lateral tibial plateaus, full extension may aid reduction through pressure applied by medial or lateral femoral condyle congruence, whereas fractures confined completely within the intercondylar notch may not reduce. Portions of the ACL are tight in all knee positions; therefore there may not be any one position that exists without traction being applied by the ACL which may prevent anatomic reduction. Radiographs are utilized to assess the adequacy of reduction.

Closed reduction can be successful for some type 2 fractures, but is frequently not successful for type 3 fractures. In their series, Kocher et al. (136) reported closed reduction in approximately 50% of type 2 fractures (26/49) with unsuccessful closed reduction in all 57 of the type 3 fractures. Arthroscopic or open reduction with internal fixation of type 2 and 3 tibial eminence fractures that do not reduce has been advocated due to the potential for clinical instability and loss of extension associated with closed reduction and immobilization, the ability to evaluate and treat injuries, and the opportunity for early mobilization (124, 142, 143 and 144). For displaced type 2 and 3 fractures, Wiley and Baxter found a correlation between fracture displacement with measured knee laxity despite good patient function (5, 119).

The author’s algorithm for the treatment of tibial spine fractures is shown in Figure 31-28.

Type 1 fractures are treated with cast immobilization after aspiration of the hematoma. A local anesthetic can be injected into the joint under sterile conditions if the patient is in severe
pain. A long-leg cast is applied in 0 to 20 degrees of flexion; we usually avoid a cylinder cast due to slippage and malleolar irritation. The patient and family are cautioned to elevate the leg to avoid swelling. Radiographs are repeated in 1 to 2 weeks to ensure that the fragment has not displaced and alignment is adequate. The cast is removed 6 weeks after injury. A hinged knee brace or a custom ACL brace is used, and physical therapy is initiated to regain motion and strength. Patients are typically allowed to return to sports at 3 months after injury if they demonstrate fracture healing and adequate motion and strength; the use of an ACL is encouraged for 6 months.

Type 2 fractures are initially treated with an attempt at closed reduction. The hematoma is aspirated and local anesthetic is injected into the knee under sterile conditions. Reduction is attempted at both full extension and 20 degrees of flexion. Radiographs are taken to assess reduction. If anatomic reduction is obtained, a long-leg cast is applied in the position of reduction and the protocol for type 1 fractures is followed. If the fracture does not reduce adequately or if the fracture displaces later, operative treatment is performed.

Type 3 fractures may be treated with attempted closed reduction; however this is usually unsuccessful and operative treatment is typically performed.

The author’s preferred operative treatment is arthroscopic reduction and internal fixation. Open reduction through a medial parapatellar incision can also be performed per surgeon preference and/or experience or if arthroscopic visualization is difficult.

A standard arthroscopic operating room setup is utilized. The patient is placed supine and general anesthesia is typically used. A standard arthroscope can be used in most patients while a small (2.7 mm) arthroscope is used in younger children. An arthroscopic fluid pump is used at 35 torr in order to prevent excess bleeding and a tourniquet is routinely used. Standard anteromedial and anterolateral portals are established and accessory superomedial and superolateral portals are used for screw insertion. The hematoma is evacuated prior to the insertion of the arthroscope.

A thorough arthroscopic examination of the entire knee joint is conducted to evaluate for concomitant injuries. Frequently, we excise some portion of the anterior fat pad and ligamentum mucosum with an arthroscopic shaver for complete visualization of the intercondylar eminence fragment. An entrapped meniscus or intermeniscal ligament can be extracted with an arthroscopic probe and retracted with a retention suture inserted from outside in (Fig. 31-27). The base of the tibial eminence fragment is elevated (Fig. 31-29A) and the entire fracture bed debrided with an arthroscopic shaver and hand curette (Fig. 31-29B). Anatomic reduction is obtained using a probe, microfracture pick, or Kirschner wire with the knee in 30 to 90 degrees of flexion (Fig. 29-19C). Cannulated guide wires are placed through portals just off the superomedial and superolateral borders of the patella through the accessory portals at the base of the ACL. Fluoroscopic assistance is utilized to confirm anatomic reduction, guide correct wire orientation, and avoid the proximal tibial physis. A cannulated drill is used over the guide wires, and one or two screws are inserted based on the size of the tibial eminence fragment (Fig. 31-29D). Partially threaded 3.5-mm diameter screws (Fig. 31-29E) are used in children and 4.5-mm diameter screws are used in adolescents. The knee is evaluated through a full range of motion to ensure rigid fixation without fracture displacement and to ensure that there is no impingement of the screw heads in extension.

Postoperatively, patients are placed in a postoperative hinged knee brace and maintained touchdown weight bearing for 6 weeks postoperatively. Motion is restricted to 0 to 30 degrees for the first 2 weeks, 0 to 90 degrees for the next 2 weeks, and then full range of motion. The brace is kept locked in extension at night. Radiographs are obtained to evaluate the maintenance of reduction and fracture healing at 2 and 6 weeks (Fig. 31-30A-D). Cast immobilization in 20 to 30 degrees of flexion for 4 weeks postoperatively may be necessary in younger children unable to comply with protected weight-bearing and brace immobilization. Physical therapy is utilized to achieve motion, strength, and sport-specific training. Patients are typically allowed to return to sports at 12 to 16 weeks postoperatively depending on knee function and strength. Screws are not routinely removed. Functional ACL bracing is utilized if there is residual knee laxity.

Arthroscopic setup and examination is similar to the technique described for epiphyseal screw fixation. Accessory superomedial and superolateral portals typically are not used. A small incision is made just medial and distal to the tibial tubercle as would be performed for an ACL reconstruction. After the fracture is debrided and slightly overreduced, a tibial ACL guide system with the tibial aimer set at 55 degrees is used to place two guide wires through the base of the ACL. The guide wires will traverse the tibial physis, but no cases of growth arrest after suture fixation have been reported. The guide wires are exchanged for Hewson suture passers and two heavy absorbable sutures are passed through the Hewson suture passers and the base of the ACL using a suture punch (Fig. 31-31A-C) or a suture lasso. The sutures are retrieved through the tibial tubercle incision, and the sutures are tied down onto the tibia. The procedure may be repeated for additional sutures. The postoperative protocol is the same (Fig. 31-32A-D).