Clinical diagnosis of medial plica syndrome of the knee: a prospective study.

Clinical diagnosis of symptomatic medial plica that causes anteromedial knee pain is poorly defined in the literature; therefore, arthroscopy is considered to be the gold standard for diagnosing this condition. We report our system of clinical diagnosis for medial plica syndrome that is based on patient history and our criteria for clinical examination. This prospective study included 48 symptomatic patients (66 knees) with clinical suspicion of pathological medial plica based on five essential and four desirable criteria. All patients underwent arthroscopic examination to confirm or disprove the clinical diagnosis and also treatment. Arthroscopy confirmed the clinical diagnosis of medial plicae in 44 patients (62 knees) for a diagnostic accuracy of 91.7% (95% confidence interval [CI]: 80% to 97.7%) and sensitivity of 100% (95% CI: 92% to 100%). The 44 patients with pathological medial plicae at arthroscopy were treated by arthroscopic resection. Thirty-nine patients (55 knees) showed satisfactory outcome after arthroscopy (95% CI: 75.4%, 96.2%). Our method of clinical diagnosis of pathological medial plica is simple, inexpensive, noninvasive, and reliable. We conclude arthroscopy is successful in treating this condition.