Baseline characteristics of participants and interventions
| Characteristic | Arthroscopic surgery (n=88) | Non-operative (n=80) |
|---|---|---|
| Male—n (%) | 34 (39) | 23 (28) |
| Age (years)* | 58.3±9.8 | 60.5±9.9 |
| Body mass index† | 31.6±6.6 | 30.2±6.4 |
| Kellgren-Lawrence grade—n (%)‡ | ||
| 2 | 42 (48) | 34 (42) |
| 3 | 41 (47) | 42 (53) |
| 4 | 5 (6) | 4 (5) |
| Symptoms of catching or locking—n (%) | 43 (49) | 37 (46) |
| WOMAC total score* | 1222.9 (478.2) | 1354.1 (545.5) |
| SG utility score | 0.79 (0.22) | 0.80 (0.21) |
| Non-operative treatment—n (%) | ||
| Medical therapy | ||
| Non-steroidal anti-inflammatory drugs | 53 (58) | 48 (56) |
| Acetaminophen | 53 (58) | 43 (50) |
| Chondroitin sulfate or glucosamine | 28 (30) | 25 (29) |
| Hyaluronic acid injection | 39 (42) | 33 (38) |
| Physical therapy§ | 9.3±5.1 | 8.0±5.7 |
| Use of brace | 3 (3) | 5 (6) |
| Surgical treatment—n (%) | ||
| Debridement of articular cartilage | 83 (97) | |
| Debridement or partial resection of meniscus | 70 (81) | |
| Excision of osteophytes | 8 (9) | |
| Removal of loose bodies | 12 (14) | |
*Mean (SD).
†Body mass index is the weight in kilograms divided by the square of the height in metres.
‡Scale that evaluates the radiographic severity of osteoarthritis.
§Average number of physical therapy sessions attended in the first 3 months since randomisation.
SG, Standard Gamble; WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index.