The Stiff Total Knee Arthroplasty: Evaluation and Treatment

Chapter Preview

CHAPTER SYNOPSIS

The incidence of stiffness following total knee arthroplasty is reported to be approximately 10%. The purpose of this chapter is to define a systematic approach toward the evaluation and treatment of patients with stiff knee replacements. In addition, special emphasis will be placed on techniques and pearls for exposure and subsequent knee reconstruction.

IMPORTANT POINTS

1

Manipulation under anesthesia may be an effective method to treat stiffness in patients with well-fixed and balanced total knee replacements.
2

Stiffness may be a manifestation of joint inflammation. Prior to revision arthroplasty, deep prosthetic joint infection should be ruled out.
3

Exposure of the stiff knee should be carried out patiently and systematically. Thorough debridement of scar tissue from the gutters, mobilizing the extensor mechanism laterally, and externally rotating the tibial component decrease the risk of patellar tendon injury.
4

Restoration of posterior femoral condylar offset is essential for maximizing knee flexion and minimizing flexion gap imbalance and impingement.
5

A quadriceps snip may be used to expose the stiff total knee replacement and does not alter the postoperative rehabilitative course.
6

In cases of extreme joint ankylosis, a tibial tubercle osteotomy can be performed. In such cases, a tapered and long osteotomy of the proximal tibia decreases the risk of nonunion and tubercle migration.

CLINICAL/SURGICAL PEARLS

1

The stiff knee should be approached via a standard medial parapatellar exposure.
2

Scar tissue should be completely debrided from the medial and lateral gutters.
3

The patella does not need to be everted during revision total knee replacement.
4

The medial collateral ligament should be completely and circumferentially released from the proximal tibia. This will allow for external rotation of the tibia and removal of the polyethylene insert.
5

If the patellar tendon is thought to be at risk, its insertion to the tibial tubercle can be protected either using sutures or a Steimann pin.
6

A quadriceps snip should be performed at 4 to 5 cm from the superior pole of the patella at a 45-degree angle.
7

When performing a tibial tubercle osteotomy, a tapered and long piece of the proximal tibia should be resected to facilitate later reattachment.
8

Reconstruction of knee should focus on the restoration of posterior condylar offset and achieving balance of the flexion and extension gaps.

CLINICAL AND SURGICAL PITFALLS

1

Failure to free the gutters will lead to suboptimal exposure and put the patellar tendon at risk.
2

If the patella is everted, it should be done with care to protect against an avulsion of the patellar tendon from the tibial tubercle.
3

Performing an extensive lateral release will help mobilize the extensor mechanism but will significantly devascularize the patella.
4

A quadriceps snip performed too close to the superior pole of the patella and at too sharp an angle risks transection of the quadriceps tendon.
5

A thin and short tubercle osteotomy is difficult to reattach and risks graft migration and nonunion.
6

Failure to restore posterior femoral offset will lead to not only flexion gap imbalance but also loss in range of motion.

VIDEO AVAILABLE

Not available

HISTORY/INTRODUCTION/SCOPE OF THE PROBLEM

Stiffness following total knee replacement (TKR) is a potentially significant source of pain, impairment, and patient dissatisfaction. Clinically important stiffness is a challenging surgical problem because of difficult surgical exposure, extensive soft tissue dissection, and prolonged patient rehabilitation. In general, stiffness is defined as suboptimal range of motion following surgery with limited flexion and an arc of motion less than 90 degrees. The causes of loss of motion are varied, ranging from infection to joint imbalance and instability, arthrofibrosis, and heterotopic bone formation. The purpose of this chapter is to present a systematic evaluation and treatment strategy that addresses stiffness following total knee arthroplasty.

INDICATIONS/CONTRAINDICATIONS

The reported incidence of stiffness following TKR is between 1.3% and 12%. This problem should be approached in a systematic fashion, directed first at delineating the cause(s) of loss of motion. A history of the involved joint including prior surgeries (arthroplasty and nonarthroplasty), prior history of joint sepsis, and if possible, preoperative and postoperative range(s) of motion should be obtained. The timing of onset of stiffness is another important consideration in the evaluation process. A sudden loss of motion in a previously well functioning knee suggests mechanical failure, loosening, or a hematogenous infection. In general, patients with flexion limited to 90 degrees or less, moderate to severe pain, and important functional impairment should be considered for treatment. Reflex sympathetic dystrophy should be considered in patients with severe pain out of proportion to physical examination findings, skin discoloration, hyper/hypohydrosis, and temperature disparities between the affected and unaffected limbs. Contraindications for treatment include painless stiff TKR, extensor mechanism deficiencies, active prosthetic joint infection, and severe medical comorbidity, regional pain syndrome or dystrophy, and severe osteoporosis.

NONOPERATIVE MANAGEMENT

As it is true with most complications in orthopedic surgery, the best course of treatment is prevention. Prior to TKR surgery, patients should be counseled about the need for aggressive rehabilitation following the procedure. Patients with posttraumatic arthritis and other conditions associated with poor preoperative range of motion should be regarded as high risk to develop postoperative joint contractures and loss or motion. The use of adjunctive modalities such as cold compression or cryotherapy has also shown to decrease swelling and pain and improve immediate postoperative range of motion. Finally, high-risk patients should be closely followed at regular intervals (2, 6, and 12 weeks and 6 months) in order to detect recurrent stiffness.

MANIPULATION

Patients who fail to reach 90 degrees of flexion at 6-week follow-up should be considered for manipulation under anesthesia, although the timing and actual range of motion that trigger a manipulation are flexible. The timing of the procedure is a balance between allowing the patient to continue to make gains with time and exercise, and the rate of fibrosis that inhibits knee motion. While the appropriate energy needed for a successful manipulation is hard to quantify, it is reasonable to assume that earlier manipulation may be gentler and cause less damage to the surrounding soft tissues of the knee. Previous studies have shown that patients with well-balanced, aligned, and appropriately sized TKAs may significantly benefit from manipulation under anesthesia. Risks of the procedure include fracture, patellar tendon avulsion, and, rarely, wound dehiscence.

In our practice, manipulation under anesthesia is performed between 6 to 10 weeks following surgery. Anesthesia takes the form of an epidural or long active spinal injection coupled with a brief general anesthetic that allows for complete paralysis and relaxation. The hip is then brought to flexion, and with the hand on the proximal tibia, a gentle and steady force is applied to the knee. Postoperatively, the patient is placed in a continuous passive motion machine (0 to 120) for a minimum of 8 hours. The patient is subsequently discharged the following day to receive outpatient physical therapy for a minimum of 5 consecutive days.

SURGICAL MANAGEMENT

Surgical management may be indicated when nonoperative management fails or when knee stiffness is identified between 6 and 12 months following surgery. Options for operative treatment include (1) arthroscopy, (2) polyethylene exchange alone, (3) revision of the femoral component, and (4) revision of both femoral and tibial components. The procedure that is indicated depends on a combination of host and surgical factors ( Fig. 28-1 ). Prior to surgery, evaluation of all possible sources of failure should be carried out. Laboratory studies should include a complete blood count (CBC with differential), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP). Radiographic evaluation should include plain radiographs (anteroposterior, lateral, and Merchant views) and a computed tomography scan if component malrotation or patellar maltracking is suspected. All knees should be aspirated prior to revision TKR.

ARTHROSCOPY

Arthroscopic debridement of a stiff TKR has gained popularity in recent years. The advantage of this procedure is that it is relatively less invasive and may reduce the wound-related morbidity associated with open arthrotomy. Drawbacks include potential damage to the tibial or femoral components and the polyethylene insert. Arthroscopic access to the posterior aspect of the knee may also be limited.

Arthroscopy is indicated in patients with well-fixed and balanced TKRs who continue to have unexplained pain. Generally, the procedure involves intra-articular lysis of adhesions coupled with manipulation under anesthesia. Ideally, the patient should be no more than 6 months past the initial surgery.

Following the induction of general anesthesia, the patient is placed supine and the leg is prepared in the standard fashion. In contrast to the standard portals used in routine knee arthroscopy, the portals used when dealing with a prosthetic knee tend to be more superiorly placed to avoid polyethylene damage. We recommend that the knee first be insufflated with normal saline prior to insertion of the cannula into the anterolateral portal.

The cannula is first inserted into the suprapatellar pouch, and the anteromedial portal is established under direct visualization. A 3.5-mm shaver is used to thoroughly debride the medial and lateral gutters, the intercondylar notch, and the area surrounding the patella ( Fig. 28-2 ).