Table 1 Heterotopic ossification staging
Brookers’ classification of HO of the hip joint | Hastings and Graham’s classification | ||
|---|---|---|---|
Grade | Description | Class | Description |
1 | Bone islands in the soft tissue around the hip | Class I | HO without functional limitation |
2 | Exophytes in the pelvis or proximal end of the femur with at least 1 cm between opposing bone surfaces | Class II IIa IIb IIc | HO with functional limitation (limited ROM) Flexion/extension limitation Pronation/supination limitation Both A and B |
3 | Exophytes in the pelvis or proximal end of the femur with less than 1 cm between opposing bone surfaces | Class III IIIa IIIb IIIc | HO with ankylosis Flexion/extension limitation Pronation/supination limitation Both A and B |
4 | Bony ankylosis between proximal femur and pelvis | ||