Ipsilateral knee injury with femoral fracture. Examination under anesthesia and arthroscopic evaluation.

Forty adults with closed diaphyseal femoral fractures and no previous knee injury were prospectively studied to determine the incidence of concomitant ipsilateral extra- and intraarticular knee injury. After intramedullary nailing, examination under anesthesia and arthroscopy were performed. The mechanism of injury was high-energy trauma. Femoral fixation included 30 interlocked nails. The results of the examination showed laxity > Grade I in 52.5% of the patients. Significant arthroscopic findings included 19 partial (48%) and two complete (5%) anterior cruciate injuries; two partial (5%) and one complete (2.5%) posterior cruciate injuries; and five medial (12%) and eight lateral (20%) meniscus tears. Significant arthroscopic findings (anterior cruciate ligament or posterior cruciate ligament injuries, meniscal tear, osteochondral fracture) were noted in conjunction with effusion or laxity > Grade I in more than half of the group, and such findings were present in one third despite absence of effusion or laxity. This study documented the incidence and array of findings noted at arthroscopy. In all, 22 patients (55%) had significant arthroscopic findings. A high incidence of knee injuries, including many that were occult, occurred in conjunction with ipsilateral femoral shaft fractures. Based on these findings, the authors recommend a high index of suspicion for coexisting knee injuries with ipsilateral femoral fracture and use of appropriate diagnostic and therapeutic measures.