Poor Long-term Clinical Results of Saddle Prosthesis After Resection of Periacetabular Tumors
Bibliographic record
Abstract
BACKGROUND: The saddle prosthesis originally was developed to reconstruct large acetabular defects in revision hip arthroplasty and was used primarily for hip reconstruction after periacetabular tumor resections. The long-term survival of these reconstructions is unclear. QUESTIONS/PURPOSE: We therefore examined the long-term function, complications, and survival in patients treated with saddle prostheses after periacetabular tumor resection. PATIENTS AND METHODS: Between 1987 and 2003 we treated 17 patients with a saddle prosthesis after periacetabular tumor resection (12 chondrosarcomas, three osteosarcomas, one malignant fibrous histiocytoma, one metastasis). During followup, 11 patients died, resulting in a median overall survival of 49 months (95% CI, 30-68 months). The remaining six patients were alive without disease (mean followup, 12.1 years; range, 8.3-16.8 years). In one patient the saddle prosthesis was removed after 3 months owing to dislocation and infection. We obtained SF-36 questionnaires, Toronto Extremity Salvage Scores (TESS), and Musculoskeletal Tumor Society (MSTS) scores. RESULTS: Thirteen of 17 patients used walking assists for mobilization at last followup: eight patients required two crutches, five needed one crutch, and one did not use any walking aids. The other three patients were not able to mobilize independently and only made bed to chair transfers. The mean hip flexion in the six surviving patients was 60° (range, 40°-100°) at last followup. Local complications were seen in 14 of the 17 patients: nine wound infections, seven dislocations, and two leg-length discrepancies requiring additional surgery. In the five surviving patients with their index prosthesis still in situ, the mean MSTS score at long-term followup was 47% (range, 20%-77%), the mean TESS score was 53% (range, 41%-67%), and the mean composite SF-36 physical and mental component summaries were 43.9 and 50.6, respectively. CONCLUSION: Reconstruction with saddle prostheses after periacetabular tumor surgery has a high risk of complications and poor long-term function with limited hip flexion; therefore, we no longer use the saddle prosthesis for reconstruction after periacetabular tumor resections.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".