Osteochondritis dissecans of the knee fixed with biodegradable self-reinforced polyglycolide and polylactide rods in 24 patients.

Over a period of 7 years (1987-1994), 24 cases of osteochondritis dissecans of the knee were treated with self-reinforced polyglycolic acid (SR-PGA) and polylactic acid (SR-PLLA) rods. Rods measuring 1.1 mm, 1.5 mm and 2 mm in diameter, and 20-40 mm in length were used in the fixation of the fragment depending on the size of the lesions. There were 23 patients with osteochondritis dessicans in the medial and 1 in the lateral femoral condyle. The average age of the patients was 25 years (range: 16-48). Follow-up was for 3.3 years (range: 1-7.6). There were 6 lesions in situ, 3 early separations, 11 were partially detached, and there were 4 loose bodies. SR-PGA rods were used in 12 patients, SR-PLLA rods in 11 patients, and both SR-PGA and SR-PLLA rods in 1 patient. The rod in each case was inserted subchondrally and in 9 cases arthroscopically, using a special instrument. In our study, the clinical result was excellent in 13 patients, good in 6, fair in 1 and poor in 4. On radiological assessment the fragment had healed in 19 cases. Synovitis occurred in 1 patient in the SR-PGA group (1/13): the effusion continued for 6 months postoperatively but, after treatment by needle aspiration, there were no symptoms at follow-up 4.2 years later. We conclude that SR-PGA and SR-PLLA rods can be used intra-articularly for the adequate fixation of osteochondritis dissecans.