Table 1.
Comparative features between spacer groups
| Comparative features | Male-female (first generation) | Lap joint (second generation) | p Value |
|---|---|---|---|
| Patient and tumor demographics | |||
| Age (years; mean ± SD) | 64.8 ± 13.1 | 62.8 ± 11.4 | 0.67 |
| Primary cancer | 0.64 | ||
| Histology | 0.24 | ||
| Metastatic/myeloma (%) versus primary | 90.5% metastases | 90.9% metastases | 0.97 |
| Preoperative treatment | |||
| Preoperative radiation treatment (%) | 23.8 | 9.1 | 0.31 |
| Preoperative chemotherapy (%) | 28.6 | 45.5 | 0.19 |
| Previous operations for cancer (%) | 76.2 | 36.4 | 0.06 |
| Previous humeral operations (%) | 33.3 | 0 | 0.03 |
| Index surgery indications | |||
| Impending fracture (%) | 28.6 | 9.1 | 0.21 |
| Actual fracture (%) | 61.9 | 81.8 | 0.25 |
| Failed open reduction with internal fixation (%) | 28.6 | 0 | 0.05 |
| Resection solitary metastasis (%) | 19.0 | 9.1 | 0.46 |
| Segmental defect (%) | 90.5 | 100 | 0.29 |
| Lesion characteristics | |||
| Segmental defect size (cm; mean ± SD) | 6.5 ± 1.9 | 6.5 ± 2.5 | 0.93 |
| Defect site (%) (proximal-middle/middle/middle-distal/distal) | 42.9/38.1/14.3/4.8 | 36.4/54.5/9.1/0 | 0.84 |
| Radiodensity (lytic/mixed/blastic; %) | 81.0/4.8/0* | 90.9/0/0* | 0.60 |
| Implant sizes (mean ± SD) | |||
| Proximal stem length (cm) | 7.5 ± 1.2 | 8.2 ± 2.0 | 0.35 |
| Body size (cm) | 7.4 ± 2.7 | 6.3 ± 1.6 | 0.26 |
| Distal stem length (cm) | 6.4 ± 1.7 | 7.5 ± 1.1 | 0.09 |
| Operation details (mean ± SD) | |||
| Operative time (minutes) | 165 ± 55 | 165 ± 105 | 0.98 |
| Estimated blood loss (mL) | 665 ± 417 | 520 ± 399 | 0.37 |
| Postoperative treatment | |||
| Radiotherapy (%) | 28.6 | 63.6 | 0.19 |
| Radiotherapy dose (Gy; mean ± SD) | 28 ± 2.7 | 40.1 ± 15.7 | 0.12 |
| Hormonal/immunotherapy (%) | 28.6 | 11.1† | 0.26 |
| Chemotherapy (%) | 30.0‡ | 22.2‡ | 0.30 |
*Three cases had missing data on radiodensity from the male-female group, one missing from the lap joint group; †two cases had missing data on hormonal/immunotherapy postoperative treatment from the lap joint group; ‡one case had missing data on chemotherapy postoperative treatment from the male-female group and two from the lap joint group; SD = standard deviation.