The false positive Lachman test.
Five patients with isolated rupture of the posterior cruciate injury following road traffic accidents were noted to demonstrate a "positive Lachman test". Stress radiographs while performing the Lachman manoeuvre confirmed that all 5 patients had only a posterior cruciate injury. Attention is drawn to the "false positive Lachman test" that indicates a posterior cruciate injury. The presence of a sag sign also establishes a diagnosis of posterior cruciate rupture and a positive Lachman test in this situation must be interpreted with caution.
Kumar
V P
VP
Department of Orthopaedic Surgery, National University Hospital, Singapore.
Satku
K
K
D000328:Adult; D016118:Anterior Cruciate Ligament / Q000000981:diagnostic imaging / Q000503:physiopathology; D000070598:Anterior Cruciate Ligament Injuries; D003937:Diagnosis, Differential; D005189:False Positive Reactions; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009068:Movement; D016119:Posterior Cruciate Ligament / Q000000981:diagnostic imaging / Q000293:injuries* / Q000503:physiopathology; D011859:Radiography; D012421:Rupture; D013977:Tibia / Q000000981:diagnostic imaging / Q000503:physiopathology