chapter 8: Patellar Tilt‑Compression and the Excessive Lateral Pressure Syndrome (ELPS)


Diagnostic arthroscopy is extremely helpful in defining and quantitating articular damage in the patient who has patellofemoral disease. The initial arthroscopy, preceding lateral release, should rule out other intra‑articular pathology, quantitate and localize synovitis, correlate patellar tracking with radiographic findings, quantitate and characterize articular lesions, and rule out loose bodies elsewhere in the knee.

The surgeon may choose then to perform an arthroscopic lateral retinacular release, if this is the selected procedure. We prefer to make a short 3‑ to 4‑cm long incision immediately adjacent to the lateral patella. A nerve stimulator may be placed on the femoral nerve proximally to stimulate a quadriceps contraction under anesthesia and thereby simulate dynamic patellar tracking. The lateral retinaculum and synovium are incised with a scalpel under direct vision, and particular care is taken to release the lateral retinaculum completely, including the distal patellotibial band and the proximal epicondylopatellar band. Additionally, the author has found that partial release of any tight retropatellar tendon fat pad while raising the lateral edge of the patella is helpful. This helps divert the lateral release at this level away from the lateral meniscus and assures that any minor component of infrapatellar contracture is released. Particular care is taken to avoid the lateral meniscus. To be most effective, the lateral release should extend all the way distal to the level of the tibial tubercle (36). The vastus lateralis obliquus (VLO) of Hallisey (see Chapter 1) is released then with Mayo scissors along the fatty plane that separates it from the main vastus lateralis tendon. Care is taken to avoid the main tendon of the vastus lateralis. The procedure, when performed this way, permits release of both static and dynamic lateral patellar supports and enables the surgeon to evert the patella 90 degrees such that open debridement or arthroplasty may be undertaken selectively, taking care to preserve intact articular cartilage wherever possible. One should assure that a complete release has been achieved (37). If the surgeon has defined a consistently painful segment of the lateral retinaculum, this portion may be excised and sent for histologic examination with Gomori's trichrome stain (3), with the intent of looking for small nerve injury in the lateral retinaculum. Through the short incision, the surgeon can achieve excellent hemostasis, and postoperative hemarthrosis becomes unlikely. It is our impression that this short lateral incision introduces no significant morbidity when compared with arthroscopic lateral release, and technical accuracy, including release of the VLO and hemostasis, can be maximized.

After release, patellar tracking may be observed passively and actively using femoral nerve stimulation by the anesthesiologist. The subcutaneous tissue and skin are closed, and a compressive wrap is applied, after which motion and weightbearing are started immediately.

Complications of Lateral Retinacular Release

Busch and DeHaven (38) have reviewed the "pitfalls" of lateral retinacular release. Although this procedure will work well for the majority of patients with persistent pain associated with tilt and less severe articular degeneration, Ogilvie‑Harris and Jackson (39) have noted that results are not as good when there is more advanced patellar arthrosis.

Hemarthrosis is the most common complication of lateral release. This usually resolves after aspiration of the knee, but occasionally one may need to open the lateral peripatellar region to coagulate an arterial bleeder.

Hughston and Deese (40) have pointed out that medial subluxation may complicate lateral release. It is important to recognize this potential complication, but we have found that this rarely occurs if lateral release is done without releasing the main vastus lateralis tendon and the patient has documented prerelease lateral subluxation or tilt.

Other complications (41, 42) of lateral release include infection, deep venous thrombosis, prolonged weakness, reflex sympathetic dystrophy, dehiscence, and compensation‑related problems.






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