Quadriceps muscle atrophy and long-term recovery after knee ligamentous injury.

The aim of the study was to clarify if atrophy of the quadriceps muscle was in itself related to clinical and radiological long-term outcome of primary knee ligament surgery. At Tampere University Central Hospital clinical and radiological reexamination was performed in 61 patients on an average 40 months after primary operation of acute knee ligament injury. The study group consisted of 26 patients having clear quadriceps muscle atrophy in the injured knee at the follow-up. Thirty four patients, having equal circumference of the thighs, served as controls. One patient was excluded. The groups did not differ significantly from each other in respect to age, sex, physical activity, type of ligament injury, meniscectomy, and follow-up time. In clinical reexamination the patients with quadriceps atrophy were placed significantly more often in groups of fair or poor healing than the patients with normal quadriceps muscle, and they had also more posttraumatic osteoarthritic changes in the injured knee. According to this study it seems that quadriceps muscle atrophy plays an important role as a poor prognostic factor of knee ligament injuries being thus a good target for efforts to stop the continuous deterioration of the injured knee.