Prevalence of isolated medial, isolated lateral, and mixed medial and lateral PF cartilage damage in BOKS, FOA and MOST studies
| Definition of PF cartilage damage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Patellar (cartilage morphology score) | Either patellar or trochlear (cartilage morphology score) | ||||||||
| ≥2 | ≥3 | ≥4 | ≥5 | ≥2 | ≥3 | ≥4 | ≥5 | ||
| BOKS | Isolated medial PF damage % (n/N) | 19.6** (44/224) | 18.3** (41/224) | 12.1 (27/224) | 12.1 (27/224) | 16.1** (36/224) | 15.2** (34/224) | 16.1 (36/224) | 13.4 (30/224) |
| Isolated lateral PF damage % (n/N) | 6.25 (14/224) | 7.6 (17/224) | 9.4 (21/224) | 9.4 (21/224) | 5.4 (12/224) | 4.9 (11/224) | 14.7 (33/224) | 11.6 (26/224) | |
| Mixed PF damage % (n/N) | 55.4 (124/224) | 50.5 (113/224) | 36.2 (81/224) | 14.7 (33/224) | 68.3 (153/224) | 63.8 (143/224) | 39.7 (89/224) | 17.0 (38/224) | |
| FOA (all knees) | Isolated medial PF damage % (n/N) | 21.7** (252/1159) | 11.8**(137/1159) | 8.1**(94/1159) | 8.3**(96/1159) | 22.6**(261/1153) | 13.5**(156/1153) | 8.9**(103/1153) | 8.9** (102/1153) |
| Isolated lateral PF damage % (n/N) | 4.5 (52/1159) | 4.2 (49/1159) | 4.8 (56/1159) | 4.3 (50/1159) | 4.1 (47/1153) | 3.6 (42/1153) | 5.8 (67/1153) | 5.2 (60/1153) | |
| Mixed PF damage % (n/N) | 33.8 (392/1159) | 26.5 (307/1159) | 7.5 (87/1159) | 3.7 (43/1159) | 37.5 (432/1153) | 29.9 (345/1153) | 9.4 (108/1153) | 5.9 (68/1153) | |
| FOA (knees with measured alignment) | Isolated medial PF damage % (n/N) | 18.7** (80/428) | 11.9** (51/428) | 11.7** (50/428) | 11.5** (49/428) | 18.8** (80/426) | 13.6** (58/426) | 12.0** (51/426) | 11.0* (47/426) |
| Isolated lateral PF damage % (n/N) | 4.9 (21/428) | 5.1 (22/428) | 4.9 (21/428) | 4.7 (20/428) | 4.2 (18/426) | 3.8 (16/426) | 6.6 (28/426) | 6.3 (27/426) | |
| Mixed PF damage % (n/N) | 46.0 (197/428) | 38.1 (163/428) | 11.7 (50/428) | 6.3 (27/428) | 51.2 (218/426) | 43.9 (187/426) | 15.0 (64/426) | 10.1 (43/426) | |
| MOST | Isolated medial PF damage % (n/N) | 24.9** (404/1621) | 20.7** (404/1621) | 11.7 (189/1621) | 11.8 (192/1621) | 25.5** (412/1613) | 20.3** (327/1613) | 11.5 (185/1613) | 11.8 (190/1613) |
| Isolated lateral PF damage % (n/N) | 7.5 (122/1621) | 7.5 (122/1621) | 11.1 (180/1621) | 9.8 (159/1621) | 7.4 (120/1613) | 7.3 (118/1613) | 13.4 (216/1613) | 12.5 (202/1613) | |
| Mixed PF damage % (n/N) | 37.8 (613/1621) | 30.9 (501/1621) | 8.6 (140/1621) | 6.8 (110/1621) | 43.7 (704/1613) | 35.8 (578/1613) | 10.2 (164/1613) | 8.0 (129/1613) | |
Crude comparison (χ2) of isolated medial to isolated lateral PF cartilage damage prevalence indicates statistically significant difference: *p<0.05; **p<0.01.
BOKS, Boston Osteoarthritis of the Knee Study; FOA, Framingham Osteoarthritis Study; MOST, Multicenter Osteoarthritis Study; PF, patellofemoral.