Table 2.
Comparison of characteristics between patients with HO and patients with LR (n = 278)
| Variable | With HO, % (n) | With LR, % (n) | p value |
| 8 (21) | 10 (28) | ||
| Age in years, mean ± SD | 26 ± 14 | 26 ± 12 | 0.74 |
| Gender, % (n) | |||
| Male | 76 (16) | 61 (17) | 0.21 |
| Female | 24 (5) | 39 (11) | |
| Follow-up in months, mean ± SD | 62 ± 32 | 65 ± 36 | 0.29 |
| Mean time of occurrence postoperatively in months, mean ± SD | 6 ± 4 | 18 ± 8 | <0.001a |
| Tumor type, % (n) | |||
| Osteosarcoma | 81 (17) | 89 (25) | |
| Ewing sarcoma | 9 (2) | 4 (1) | 0.42 |
| Parosteal osteosarcoma | 5 (1) | 4 (1) | |
| Periosteal osteosarcoma | |||
| Chondrosarcoma | |||
| MFH | 5 (1) | 4 (1) | |
| Leiomyosarcoma | |||
| Pain at presentation of HO or LR, % (n) | |||
| Yes | 14 (3) | 8 (24) | <0.001a |
| No | 86 (18) | 14 (4) | |
| Chemotherapy, % (n) | |||
| Yes | 95 (20) | 96 (27) | 0.83 |
| No | 5 (1) | 4 (1) | |
| Tumor stage, % (n) | |||
| IIA | 5 (1) | 7 (2) | 0.39 |
| IIB | 95 (20) | 93 (26) | |
| Tumor location, % (n) | |||
| Distal femur | 71 (15) | 75 (21) | 0.52 |
| Proximal tibia | 29 (6) | 25 (7) | |
| Length of resection in cm, mean ± SD | 18 ± 3 | 18 ± 3 | 0.33 |
| Size of lesion in cm2, mean ± SD | 4 ± 3 | 4 ± 3 | 0.21 |
a
Statistically significant (p value < 0.05); HO = heterotopic ossification; LR = local recurrence; MHF = malignant fibrous histiocytoma; MUTARS = Modular Universal Tumor and Revision System; HMRS = Howmedica Modular Reconstruction System; GMRS = Global Modular Reconstruction System.