A retrospective review of revision proximal humeral allograft-prosthetic composite procedures: an analysis of proximal humeral bone stock restoration

Reverse Allograft Prosthetic-Composite Versus Endoprosthesis Reconstruction for Massive Proximal Humerus Bone Loss: A Systematic Review and Meta-analysis of Outcomes and Complications

Background

This systematic review and meta-analysis sought to compare the clinical outcomes after proximal humerus reconstruction with a reverse allograft-prosthetic composite (APC) versus reverse endoprosthesis.

Methods

Per PRISMA guidelines, we queried PubMed/MEDLINE, Embase, Web of Science, and Cochrane databases to identify articles reporting clinical outcomes of reverse APC or reverse endoprosthesis reconstruction of the proximal humerus for massive bone loss secondary to tumor, fracture, or failed arthroplasty. We compared postoperative range of motion, outcome scores, and the incidence of complications and revision surgery.

Results

Of 259 unique articles, 18 articles were included (267 APC, 260 endoprosthesis). There were no significant differences between the APC and endoprosthesis cohort for postoperative forward elevation (P = .231), external rotation (P = .634), ASES score (P = .420), Constant score (P = .414), MSTS (P = .815), SST (P = .367), or VAS (P = .714). Rate of complications was 15% (31/213) in the APC cohort and 19% (27/144) in the endoprosthesis cohort. The rate of revision surgery was 12% after APC cohort and 7% after endoprosthesis. APC-specific complications included a 10% APC nonunion/malunion/resorption rate and 6% APC fracture/fragmentation rate.

Discussion

Reverse APC and endoprosthesis are reasonable options for proximal humerus reconstruction. APC carries additional risks for complications, warranting evaluation of patients' healing capacity and surgeon experience.

Level of Evidence

Level IV; Systematic Review.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-024-01248-7.

Complications and functional outcomes after reconstruction of the proximal humerus with allograft-prosthetic composite: a systematic review of the literature

BACKGROUND

Allograft prosthetic composite (APC) reconstruction is performed after resection of proximal humerus tumors or failure of arthroplasty implants. There is limited literature on the postoperative outcomes of this technique. We sought to assess implant survival, failure rates, and postoperative functional outcomes after APC reconstruction of the proximal humerus.

METHODS

A systematic review of the PubMed and Embase databases was conducted. The study was registered on PROSPERO (ID: 448,663). The Strengthening of the Reporting of Observational Studies in Epidemiology checklist was used for quality assessment. Implant failure was determined using the Henderson classification for biological reconstruction. Functional outcome was primarily assessed using the Musculoskeletal Tumor Society score at last follow-up.

RESULTS

Twenty-five studies with a total of 488 patients were included. Mean follow-up in reporting studies ranged from 2.5 to 10 years. Five-year revision-free survival for implants ranged from 41% to 92%. Overall implant failure rate ranged from 9% to 54%, and reoperation rate ranged from 0% to 55%. Graft host nonunion (type 2) was the most common mode of failure, with rates ranging from 0% to 75%. The mean Musculoskeletal Tumor Society scores at last follow-up ranged from 57% to 90% across studies. A trend towards better functional outcomes was seen in patients having an APC with a reverse total shoulder arthroplasty (rTSA) compared with those with hemiarthroplasty.

CONCLUSIONS

APCs show promise in proximal shoulder reconstruction, with heterogeneous functional outcomes that are noninferior to other reconstruction techniques. Graft host nonunion is a common mode of failure and remains a concern in this type of prosthesis. Future studies should compare rTSA-APCs and rTSA endoprostheses while controlling for potential confounders.

Total Humeral Endoprosthetic Reconstruction: A Systematic Review

BACKGROUND

Total humeral endoprosthetic reconstruction (THER) is a rare reconstruction option for limb salvage surgery for large humeral neoplasms or bone destruction.

MATERIALS AND METHODS

Because of the limited data and need for this procedure, we reviewed the literature surrounding THER and assessed functionality, complications, and revisions using the PubMed, Embase, Ovid, and Scopus databases.

RESULTS

Among 29 articles and 175 patients, the most common indication was neoplasm (n=25, 86%), mean follow-up was 61.98 months (SD=55.25 months), and mean Musculoskeletal Tumor Society score was 73.64% (SD=10.69%). Reported complications included 26 (23%) revisions in 7 studies, 35 (36%) cases of shoulder instability in 7 studies, and 13 (13.54%) cases of deep infection in 4 studies.

CONCLUSION

THER should be considered with a thorough knowledge of outcomes and potential complications to guide patient and clinician expectations. [Orthopedics. 2024;47(3):e106-e113.].

Allograft-Prosthetic Composite Reconstruction for Proximal Humerus Bone Loss: A Systematic Review and Meta-Analysis of Outcomes and Complications

BACKGROUND

In smaller studies, allograft-prosthetic composite (APC) has been used for proximal humerus bone loss with some success, although with notable complication risk. This systematic review and meta-analysis sought to describe outcomes and complications after proximal humerus APC and how major APC complications are defined in the literature.

METHODS

A systematic review was performed per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane were queried for articles on APC for proximal humeral bone loss secondary to tumor, fracture, or failed arthroplasty. Primary outcomes included postoperative range of motion, outcome scores (Musculoskeletal Tumor Society [MSTS], Simple Shoulder Test [SST], American Shoulder and Elbow Surgeons [ASES], Constant, visual analog scale [VAS], and subjective shoulder value [SSV]), and complication incidence. We also described individual study definitions of APC malunion/nonunion, methods of postoperative evaluation, malunion/nonunion rates, allograft fracture/fragmentation rates, and mean union time, when available. Secondarily, we compared hemiarthroplasty and reverse total shoulder arthroplasty.

RESULTS

Sixteen articles including 375 shoulders were evaluated (average age: 49 years, follow-up: 54 months). Fifty-seven percent of procedures were performed for tumors, 1% for proximal humerus trauma sequelae, and 42% for revision arthroplasty. Average postoperative forward elevation was 82° (69-94°), abduction 60° (30-90°), and external rotation 23° (17-28°). Average MSTS score was 82% (77%-87%), SST score 5.3 (4.5-6.1), ASES score 64 (54-74), Constant score 44 (38-50), VAS score 2.2 (1.7-2.7), and SSV 51 (45-58). There was a 51% complication rate with an 18% nonallograft surgical complication rate, 26% APC nonunion/malunion/resorption rate, and 10% APC fracture/fragmentation rate. Fifteen percent of nonunited APCs underwent secondary bone grafting; 3% required a new allograft; and overall revision rate was 12%. APC nonunion/malunion was defined in 2 of 16, malunion/nonunion rates in 14 of 16, fracture/fragmentation rates in 6 of 16, and mean union time (7 months) in 4 of 16 studies.

CONCLUSION

APC reconstruction of the proximal humerus remains a treatment option, albeit with substantial complication rates. In addition, there is a need for APC literature to report institutional definitions of nonunion/malunion, postoperative evaluation, and time to union for a more standardized evaluation.

LEVEL OF EVIDENCE

Level IV; systematic review. See Instructions for Authors for a complete description of levels of evidence.

[Humeral bone defects in revision shoulder arthroplasty]

BACKGROUND

Revision shoulder arthroplasty is mainly performed with reverse TSA and should consider proper adjustment of the length and the amount of bone loss in humeral reconstruction. Whilst epi-/metaphyseal bone loss can mostly be compensated easily by stemmed standard implants, advanced bone loss exceeding 2° requires the support of longer revision stems.

EXTENSIVE HUMERAL BONE LOSS

Cementless fixation in the intact diaphyseal humerus is recommended in bone loss exceeding 2°, preferably with modular revision systems, because cemented reverse revision stems have higher loosening rates in the mid to long-term follow-up. In cases of advanced bone loss 3°-4° (more than 6-7 cm), structural humeral allografts should be considered to prevent instability and early loosening. Unfortunately, the access to fresh frozen allografts is very limited due to regulation of the German government in contrast to the situation in the US or Switzerland. Reverse tumor arthroplasty is an option with a higher complication rate and inferior function even when polyester mesh is used for ingrowth of soft tissues.

DISTINCT DIAPHYSEAL DEFECTS

In bone loss 4°-5° the minimal anchorage length is mostly critical due to the curvature of the medullary canal. The fixation of a revision stem is only possible when at least 2-3 widths of the diaphyseal diameter are available. Custom-made implants with flanges or distal locking screws, or bipolar tumor arthroplasty may be required. Additionally, strut allografts can be useful to achieve stable fixation. Two-stage biological reconstruction in impaction-bone-graft or the Masquelet technique are rarely used as a salvage procedure.

Allograft prosthetic composite reconstruction using a reverse total shoulder arthroplasty for failed oncologic proximal humerus reconstruction

INTRODUCTION

Endoprosthetic or allograft reconstruction are the preferred reconstruction techniques for proximal humeral bone tumors. Failure of these reconstructions may occur, but historically revision is performed rarely due to the lack of reliable options. Reverse shoulder arthroplasty with an allograft prosthetic composite (rAPC) may provide a revision option. The purpose of the current study was to evaluate our institutional outcome of these procedures.

METHODS

Eleven (6 male, 5 female) patients (mean age 51 ± 17 years) underwent revision of a failed oncologic reconstruction of the proximal humerus utilizing a rAPC. The most common indication for revision was subluxation (n = 6) and the most common previous implant was an endoprosthesis (n = 5).

RESULTS

Revision resulted in improvements in shoulder elevation (39° vs. 62°, p = 0.02), external rotation (13° vs. 25°, p = 0.04), American Shoulder and Elbow Surgeons score (39 vs. 58, p = 0.004) and Musculoskeletal Tumor Society Scores (51% vs 69%, p = 0.002). There were 2 re-revision procedures performed. One for an allograft fracture and one for allograft resorption and loosening.

CONCLUSIONS

Revision with a rAPC can effectively restore patient function. Due to the complexity of the cases, we advocate for these procedures to be performed by subspecialty upper extremity surgeons trained in complex revision shoulder arthroplasty.

Composite-Free Vascularized Fibular Epiphyseal Flap and Proximal Humeral Allograft for Proximal Humerus Reconstruction in a Pediatric Patient

Tumors involving the epiphysis in children present a reconstructive challenge. A free vascularized fibula epiphyseal transfer offers a means for biological reconstruction and longitudinal growth; however, it is often complicated by graft fracture and limited shoulder motion. Here, we present a case of a composite structural allograft with free vascularized fibula epiphyseal transfer for proximal humeral reconstruction. At 27-month follow-up, there was longitudinal growth, hypertrophy of the epiphysis, shoulder function which allowed activities of daily living, and no graft fracture.

Custom Prosthetic Reconstruction for Severe Proximal Humeral Bone Loss Status Post Infected Arthroplasty: A Case Report

CASE

A 68-year-old male, status post revision right reverse total shoulder arthroplasty (RTSA) for periprosthetic fracture, suffered a periprosthetic joint infection necessitating 2-stage revision. Imaging revealed 8.6 cm of ipsilateral proximal humeral bone loss (PHBL) including loss of the greater and lesser tuberosities. A 2-stage revision was performed using an antibiotic spacer, followed by a custom long-stem RTSA for definitive reconstruction. Two years postoperatively, the patient had significantly improved pain and functional range of motion.

CONCLUSION

Custom long-stem RTSA could serve as a potentially viable reconstructive option in patients with severe PHBL.

Humeral stress shielding following cemented endoprosthetic reconstruction: An under-reported complication?

INTRODUCTION

The proximal humerus is a common location for primary and non-primary tumors. Reconstruction of the proximal humerus is commonly performed with an endoprosthesis with low rates of structural failure. The incidence and risk factors for stress shielding are under reported.

METHODS

Thirty-nine (19 male, 20 female) patients underwent resection of the proximal humerus and reconstruction with a cemented modular endoprosthesis between 2000 and 2018. The mean resection length was 12 ± 4 cm and was most commonly performed for metastatic disease (n = 26, 67%).

RESULTS

Stress shielding was observed in 9 (23%) patients at a mean of 29 (6-132) months postoperatively. Patients with stress shielding were noted to have shorter intramedullary stem length (87 vs. 107 mm, p < .001), longer extramedullary implant length (16 vs. 14 cm, p = .01) and a higher extramedullary implant to stem length ratio (2.1 vs. 1.1, p < .001). The incidence of stress shielding was higher (p = .003) in patients reconstructed with 75 mm stem (n = 6, 67%) lengths.

CONCLUSION

Stress shielding of the humerus was associated with the use of shorter stems and long extramedullary implants. The long-term ramifications of stress shielding on implant stability, complications at the time of revision surgery, and overall patient outcomes remain unknown.