Arthroscopic excision of the os trigonum: a new technique with preliminary clinical results.

Open excision of a painful os trigonum can be associated with prolonged recovery. An arthroscopic technique has been developed to decrease scarring, diminish surgical morbidity, and promote a faster recovery. Eleven patients were retrospectively evaluated after removal of the os trigonum after a mean follow-up of 35 months. Small joint arthroscopy equipment was utilized in a supine position with a distraction device. Average patient scores improved on the AOFAS Ankle/Hindfoot Scale from 45 to 86 points. All patients went home the same day, and no complications occurred during the procedure. All patients reached maximum recovery level within the first 3 months after surgery. Arthroscopic excision of a painful os trigonum yields good results with minimal surgical morbidity and shorter recovery time.

Late patellar tendon ruptures after removal of the central third for anterior cruciate ligament reconstruction. A report of two cases.

Patellar tendon rupture after removal of the central third for ACL reconstruction is a rare complication. Only nine cases have been previously reported, and all of these occurred within the first 10 months after surgery. We report two cases of late patellar tendon ruptures occurring at more than 3 and 6 years, respectively, after surgery. A review of the literature has suggested but not conclusively supported that devascularization, an alteration in tendon healing and remodeling, or injury to the remaining tendon at the time of graft harvest may be possible causes of this rare complication. Biopsy tissue from any future patellar tendon ruptures after removal of its central third could contribute to a better understanding of this anomaly.

Parallax radiology of the hip.

We report our use of a simple radiographic technique that uses the principle of parallax for evaluating the anterior-posterior relationship of the proximal femur to the triradiate cartilage in skeletally immature patients. Thirty-six paired plain radiograph parallax views were compared with 13 respective computed tomography scans of the hips in seven patients. All had undergone closed or open reductions and were in spica casts at the time of radiographic evaluation. The parallax views detected all cases of anterior or posterior subluxation or dislocation when present. We found this method to be reliable and easily performed in the casted patient for use in radiographically evaluating pediatric hip subluxation in the anterior-posterior dimension.

A biomechanical comparison of lateral retinacular releases.

A lateral patellar retinacular release that transects the tendon of the vastus lateralis muscle may result in significant complications. To avoid such complications, the superior extent must be limited, and maximizing the inferior extent may be important in achieving an adequate release. The effective release of the patella from its lateral retinaculum was examined for 2 incision lengths using 10 fresh-frozen human cadaveric knees and comparing the medial displacement of the patella relative to the femur for 3 study groups (control, intact retinacula; Group A, retinacula cut from the inferior third of the vastus lateralis tendon down to the anterolateral arthroscopic portal; and Group B, retinacula cut from the inferior third of the vastus lateralis tendon down to the tibial tubercle) when a 22-N medially directed force was applied to the patella with the knee at 30 degrees and 60 degrees of flexion. The extended release (Group B) resulted in a significantly more effective release when compared with the standard release (Group A) or control group. This technique may allow an adequate release of the patella while preserving the function of the vastus lateralis muscle.