Disruption of the vastus medialis obliquus with medial knee ligament injuries.

We reviewed the clinical records of 189 consecutive surgically treated acute ligamentous injuries of the medial compartment of the knee to determine the prevalence of disruptions of the vastus medialis obliquus muscle and to document the results of simultaneous repair of the disruption. Forty knees (40 patients) demonstrated a vastus medialis muscle disruption at the time of surgical repair for the medial ligamentous disruption. All were surgically corrected and the sites of tearing were documented. The vastus medialis obliquus muscle was ruptured from the adductor tubercle in 31 (78%) knees. Of these, the tibial collateral ligament was torn from its femoral attachment in 19 (61%) knees and the meniscofemoral portion of the capsular ligament ligament was torn from its femoral attachment in 23 (74%) knees. The vastus medialis obliquus muscle was ruptured from the patella in seven (18%) knees and was ruptured interstitially in nine (23%) knees. Each of the 40 patients returned for objective, subjective, and functional follow-up evaluation (average, 39 months). At follow-up examination, 88% of the 40 knees were rated as good subjectively, 90% objectively, and 93% functionally. A high correlation exists between tears of the vastus medialis obliquus muscle from its femoral attachment and tears of the medial compartment ligaments from their respective femoral attachments. Surgical repair of disruptions of the vastus medialis obliquus muscle at the time of primary repair of injury to the ligaments of the medial compartment of the knee can prevent subsequent disorder of the extensor mechanism and can produce an objectively, subjectively, and functionally stable knee.