BMC Musculoskeletal Disorders

Background: To describe a semi-quantitative score for multi-feature, whole-organ evaluation of the knee in osteoarthritis based on the results of arthroscopic evaluation. Methods: This was a study of 1,199 patients who were suffering from knee pain for over 3 months (range 3 to 48 months) and had undergone arthroscopy. The mean age of patients was 49.8 (range 17 to 85) years old. Cartilage lesions were graded according to the ICRS protocol (grade 0 to 4 and for osteophytes "grade 5"). Meniscus lesions were classified regarding to the extent of resection which was needed (grade 0: intact meniscus, grade 1: partial meniscectomy, grade 2: subtotal meniscectomy, and grade 3: total meniscectomy). The whole grade of cartilage lesions was calculated as the sum of ICRS grades in all joint surfaces (bearing and non-bearing margin). The whole grade of meniscus lesions was calculated as the sum of the points for medial and lateral meniscus surgery. The Whole-Organ Arthroscopic Knee Score (WOAKS) was the sum of the cartilage and meniscus score. Results: The mean knee osteoarthritis outcome score (KOOS) of all patients was 67.3 ± 26.0 (range 21 to 128) points. The WOAKS was significantly associated (p = 0.001) with patient age (R = 0.399), the subjective complaints (R = 0.630) in KOOS, and the radiological grade of OA