Pitfalls in lateral retinaculum release [Gli insuccessi nel release del retinacolo laterale]

Lateral retinaculum release (LRR) is a commonly performed procedure with variable acceptable (good and excellent) results, from 14% to 99%. LRR has been used to treat various patello-femoral disorders, such as anterior knee pain, patellar instability, acute and recurrent patellar dislocation, chondromalacia patellae, P/F arthrosis but only lateral hyperpression syndrome is associated with satisfactory results. In the absence of documented patellar tilt, LRR is fraught with pitfalls about indications and diagnosis, surgical procedure, complications and patient compliance. LRR is recommended for patients with patello-femoral pain and a tight lateral retinaculum after a period of at least 6 months of conservative treatment. Results may be compromised by chondral degeneration. Dislocation of the patella is frequently associated with a hypermobile patella: release of the lateral restraint in the presence of an already incompetent medial restraint may ultimately result in patellar malalignment and hypermobiltty. LRR can be performed as open, mini-open, arthroscopically assisted or all-arthroscopic procedure. The most important error in surgical technique is related to the extension of the release. Over-release of the vastus lateralis can affect the normal quadriceps kinematics, with muscle atrophy and quadriceps tendon rupture. Under-release is generally due to an incomplete dissection of patello-tibial ligament. The overall complication rate in LRR is 7,2-11%. Hemarthrosis is the most frequent complication; negative prognostic factors are the use of a tourniquet, the percutaneous technique, post-operative suction drain for 24 hours or longer. Recurrent medial subluxation of the patella is a rare, disabling condition that can be the result of an excessive lateral retinacular of both open and arthroscopic technique. Conservative treatment is recommended and surgical correction must be considered only as a salvage procedure. Lateral release is capable of producing high rates of success with a low incidence of complications when used with the proper indication and surgical technique