TABLE 5.
Comparison between IOR Classification and revised IOR Classification patient distributions
| IOR Class | N (%) | IOR Subclassification | N (%) | Revised IOR Subclassification | N (%) | |
|---|---|---|---|---|---|---|
| <10 years | I | 149 (61.3) | IA (≤5 sites with OC) | 71 (29.2) | IA (≤5 sites with OC) | 71 (29.2) |
| IB (>5 sites with OC) | 78 (32.1) | IB (>5 sites with OC) | 78 (32.1) | |||
| II | 70 (28.8) | IIA (≤5 sites with deformities) | 69 (28.4) | IIA (≤2 sites with deformities) | 55 (22.6) | |
| IIB (>5 sites with deformities) | 1 (0.4) | IIB (>2 sites with deformities) | 15 (6.2) | |||
| III | 24 (9.9) | IIIA (1 site with functional limitation) | 18 (7.4) | IIIA (1 site with functional limitation) | 18 (7.4) | |
| IIIB (>1 site with functional limitation) | 6 (2.5) | IIIB (>1 site with functional limitation) | 6 (2.5) | |||
| 10–15 years | I | 62 (45.6) | IA (≤5 sites with OC) | 31 (22.8) | IA (≤5 sites with OC) | 31 (22.8) |
| IB (>5 sites with OC) | 31 (22.8) | IB (>5 sites with OC) | 31 (22.8) | |||
| II | 55 (40.4) | IIA (≤5 sites with deformities) | 50 (36.8) | IIA (≤2 sites with deformities) | 33 (24.3) | |
| IIB (>5 sites with deformities) | 5 (3.7) | IIB (>2 sites with deformities) | 22 (16.2) | |||
| III | 19 (14.0) | IIIA (1 site with functional limitation) | 10 (7.4) | IIIA (1 site with functional limitation) | 10 (7.4) | |
| IIIB (>1 site with functional limitation) | 9 (6.6) | IIIB (>1 site with functional limitation) | 9 (6.6) | |||
| ≥16 years | I | 241 (40.9) | IA (≤5 sites with OC) | 77 (13.1) | IA (≤5 sites with OC) | 77 (13.1) |
| IB (>5 sites with OC) | 164 (27.8) | IB (>5 sites with OC) | 164 (27.8) | |||
| II | 162 (27.5) | IIA (≤5 sites with deformities) | 152 (25.8) | IIA (≤2 sites with deformities) | 95 (16.1) | |
| IIB (>5 sites with deformities) | 10 (1.7) | IIB (>2 sites with deformities) | 67 (11.4) | |||
| III | 186 (31.6) | IIIA (1 site with functional limitation) | 76 (12.9) | IIIA (1 site with functional limitation) | 76 (12.9) | |
| IIIB (>1 site with functional limitation) | 110 (18.7) | IIIB (>1 site with functional limitation) | 110 (18.7) | |||
| OVERALL | I | 452 (46.7) | IA (≤5 sites with OC) | 179 (18.5) | IA (≤5 sites with OC) | 179 (18.5) |
| IB (>5 sites with OC) | 273 (28.2) | IB (>5 sites with OC) | 273 (28.2) | |||
| II | 287 (29.6) | IIA (≤5 sites with deformities) | 271 (28.0) | IIA (≤2 sites with deformities) | 183 (18.9) | |
| IIB (>5 sites with deformities) | 16 (1.7) | IIB (>2 sites with deformities) | 104 (10.7) | |||
| III | 229 (23.7) | IIIA (1 site with functional limitation) | 104 (10.7) | IIIA (1 site with functional limitation) | 104 (10.7) | |
| IIIB (>1 site with functional limitation) | 125 (12.9) | IIIB (>1 site with functional limitation) | 125 (12.9) |
Abbreviations: IOR, Istituto Ortopedico Rizzoli; OC, osteochondroma(s).