Large osteochondral fractures of the lateral femoral condyle in the adolescent: outcome of bioabsorbable pin fixation.

BACKGROUND

Large osteochondral fractures of the lateral femoral condyle of the knee in adolescent patients can be diagnostically and therapeutically challenging. Historically, management has involved removal of the fragment, leaving a large area of bone devoid of articular cartilage on the weight-bearing surface of the lateral femoral condyle. This study assessed open reduction and internal fixation of the osteochondral fragments with use of multiple polyglycolic acid rods.

METHODS

Eight patients, between twelve and fifteen years old, with a large (>4 cm(2)) osteochondral fracture of the lateral femoral condyle were treated with open reduction and internal fixation with use of multiple polyglycolic acid rods. Each patient was evaluated at more than five years (a mean of nine years) after the index procedure with a clinical assessment, during which the knee was scored according to the International Knee Documentation Committee and Cincinnati knee rating systems, plain radiographs were made, and magnetic resonance imaging scans were acquired.

RESULTS

The majority of patients scored well on both knee rating systems, with no poor results. Five of the eight patients had normal findings on knee radiographs, and three had radiographs that showed minor changes. Magnetic resonance imaging scans of all patients demonstrated intact articular cartilage in the lateral compartment with no area of full-thickness articular cartilage loss. No evidence of articular cartilage thinning was seen in two knees; a small area of <2 cm(2) of cartilage thinning, in four; a moderate area of 2.7 cm(2) of cartilage thinning, in one; and a large area of 11.2 cm(2) of abnormal cartilage signal, in one knee.

CONCLUSIONS

Osteochondral fracture of the lateral femoral condyle is an injury to which adolescents with ligamentous laxity of the knee are prone. Our results show that internal fixation of these osteochondral fragments with bioabsorbable implants is possible and is a worthwhile option.