Internal derangement of the knee after ipsilateral femoral shaft fracture : MR imaging findings

• Published in: Skeletal radiology 1998-08, Vol.27 (8), p.434-439
• Main Authors: BLACKSIN, M. F, ZURLO, J. V, LEVY, A. S
• Format: Article
• Language: English
• Subjects: Adult; Anterior Cruciate Ligament Injuries; Biological and medical sciences; Female; Femoral Fractures - complications; Femoral Fractures - pathology; Humans; Investigative techniques, diagnostic techniques (general aspects); Knee; Knee - pathology; Knee Injuries - etiology; Knee Injuries - pathology; Magnetic Resonance Imaging; Male; Medical sciences; Osteoarticular system. Muscles; Posterior Cruciate Ligament - injuries; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Sports injuries; Sports medicine; Tendon Injuries - etiology; Tendon Injuries - pathology; Tibial Meniscus Injuries
• ISSN: 0364-2348; 1432-2161
• DOI: 10.1007/s002560050413

This study uses magnetic resonance (MR) imaging to delineate the types and frequencies of injuries seen in the knee after ipsilateral femoral shaft fracture. We also compare the results of the orthopedic knee examination with the MR findings. MR imaging of the ipsilateral knee was performed on 34 patients with closed femoral shaft fractures. Indications for knee MR imaging included knee pain at the time of fracture, soft tissue swelling or an effusion of the knee, or a positive knee examination under anesthesia. The patients had a mean age of 27 years and all were stabilized with intramedullary nails. Imaging was performed a mean time of 2.5 days after surgery. All patients had knee examinations done under anesthesia, and the MR results were compiled and compared with the clinical examinations. Ninety-seven percent of patients demonstrated knee effusions. Twenty-seven percent of patients demonstrated meniscal tears, with the posterior horn of the medial meniscus most frequently torn. The medial collateral ligament was the most frequent site of ligamentous injury (38%) followed by the posterior cruciate ligament (21%). Fifty percent of patients had injuries of the extensor mechanism. Bone bruises were noted in 32% of patients. Articular cartilage injuries were confined to the patella in four cases. One occult tibial plateau fracture and one meniscocapsular separation were seen. There is a common incidence of both ligamentous and meniscal injury to the knee after ipsilateral femoral shaft fracture. MR imaging can be useful in assessing the extent of injury, and may reveal findings unsuspected after clinical examination of the knee.