Signs of osteoarthritis (OA; based on the KOSS scoring system) and presence of knee OA on the 6-year MRI, compared with the K&L score for knee OA on the 6-year radiograph, their relation with the K&L score (grade 0 vs grade 1 and 2) and their relation with persistent knee symptoms at 6-year follow-up (n=47)
| K&L score on 6-year radiograph | ||||||
|---|---|---|---|---|---|---|
| Grade 0 (n=28) n (%) | Grade 1 (n=13) n (%) | Grade 2 (n=6) n (%) | K&L score (grade 0 vs 1 and 2) OR (95% CI) | Persistent knee symptoms OR (95% CI) | ||
| Signs of OA on 6-year MRI Frequency (n=47) n (%) | ||||||
| Chondral defect | 26 (55.3) | 10 (35.7) | 10 (76.9) | 6 (100.0) | 9.6 (2.2 to 41.1)* | 2.3 (0.7 to 8.4) |
| Medial | 22 (46.8) | 6 (21.4) | 10 (76.9) | 6 (100.0) | 19.6 (4.2 to 90.2)* | 1.8 (0.5 to 6.0) |
| Lateral | 15 (31.9) | 5 (17.9) | 5 (38.5) | 5 (83.3) | 5.1 (1.4 to 19.2)* | 5.4 (1.4 to 20.3)* |
| Osteophytes† | 21 (44.7) | 7 (25.0) | 8 (61.5) | 6 (100.0) | 8.4 (2.2 to 31.8)* | 3.0 (0.9 to 10.6) |
| Medial | 19 (40.4) | 5 (17.9) | 8 (61.5) | 6 (100.0) | 12.9 (3.2 to 52.6)* | 4.1 (1.1 to 14.6)* |
| Lateral | 13 (27.7) | 4 (14.3) | 4 (30.8) | 5 (83.3) | 5.4 (1.3 to 21.7)* | 2.1 (0.6 to 7.7) |
| Subchondral cyst | 17 (36.2) | 5 (17.9) | 7 (53.8) | 5 (83.3) | 7.9 (2.1 to 30.2)* | 1.6 (0.5 to 5.7) |
| Medial | 11 (23.4) | 2 (7.1) | 5 (38.5) | 4 (66.7) | 11.7 (2.1 to 63.8)* | 1.9 (0.5 to 7.5) |
| Lateral | 7 (14.9) | 3 (10.7) | 3 (23.1) | 1 (16.7) | 2.2 (0.4 to 11.3) | 1.6 (0.3 to 8.0) |
| Bone marrow oedema | 19 (40.4) | 7 (25.0) | 8 (61.5) | 4 (66.7) | 5.1 (1.5 to 18.2)* | 1.8 (0.5 to 6.2) |
| Medial | 14 (29.8) | 4 (14.3) | 6 (46.2) | 4 (66.7) | 6.6 (1.7 to 26.8)* | 1.7 (0.5 to 6.3) |
| Lateral | 7 (14.9) | 3 (10.7) | 3 (23.1) | 1 (16.7) | 2.2 (0.4 to 11.3) | 3.1 (0.6 to 16.1) |
| Meniscal subluxation‡ | 10 (21.3) | 2 (7.1) | 3 (23.1) | 5 (83.3) | 9.5 (1.7 to 51.9)* | 7.3 (1.5 to 34.1)* |
| Medial | 10 (21.3) | 2 (7.1) | 3 (23.1) | 5 (83.3) | 9.5 (1.7 to 51.9)* | 7.3 (1.5 to 34.1)* |
| Lateral | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | − | − |
| Meniscal degeneration‡ | 39 (83.0) | 21 (75.0) | 12 (92.3) | 6 (100.0) | 6.0 (0.7 to -53.5) | 4.4 (0.5 to 39.2) |
| Medial | 32 (68.1) | 17 (60.7) | 11 (84.6) | 4 (66.7) | 2.4 (0.6 to 9.3) | 1.0 (0.3 to 3.8) |
| Lateral | 18 (38.3) | 6 (21.4) | 7 (53.8) | 5 (83.3) | 6.3 (1.7 to 23.0)* | 3.1 (0.9 to 11.0) |
| Effusion‡ | 5 (10.6) | 2 (7.1) | 2 (15.4) | 1 (16.7) | 2.4 (0.4 to 16.2) | 1.3 (0.2 to 8.9) |
| Baker's cyst | 5 (10.6) | 4 (14.2) | 1 (7.7) | 0 (0.0) | − | 2.0 (0.1 to 34.2) |
| Knee OA on 6-year MRI§ | 17 (36.2) | 3 (10.7) | 8 (61.5) | 6 (100.0) | 23.3 (4.8 to 112)* | 3.7 (1.0 to 13.2)* |
* p≤0.05.
†≥2 minimal osteophytes or ≥1 moderate or severe osteophyte(s) in the lateral or medial compartment of the femorotibial joint.
‡Moderate and severe.
§Definition according to Hunter et al.
K&L score, Kellgren & Lawrence score; KOSS, Knee Osteoarthritis Scoring System; OA, osteoarthritis.