Instability after major tumor resection: prevention and treatment

Pelvic-girdle reconstruction with three-dimensional-printed endoprostheses after limb-salvage surgery for pelvic sarcomas: current landscape

Resection of pelvic bone tumors and the subsequent reconstruction of the pelvic girdle pose challenges due to complex anatomy, load-bearing demands, and significant defects. 3D-printed implants have revolutionized pelvic girdle reconstruction by offering customized solutions, porous surface structures for precise resection with custom guides, and improved integration. Many tertiary medical centers have adopted 3Dprinted hemipelvic endoprostheses, leading to enhanced outcomes. However, most studies are limited to single centers, with a small number of cases and short follow-up periods. Additionally, the design of these implants often relies heavily on individual experience, resulting in a lack of uniformity and significant variation. To provide a comprehensive assessment of this technology, we conducted an analysis of existing literature, encompassing tumor resection classification, various types of prosthesis design, reconstruction concepts, and post-reconstruction functional outcomes.

A Conceptual Blueprint for Making Neuromusculoskeletal Models Clinically Useful

The ultimate goal of most neuromusculoskeletal modeling research is to improve the treatment of movement impairments. However, even though neuromusculoskeletal models have become more realistic anatomically, physiologically, and neurologically over the past 25 years, they have yet to make a positive impact on the design of clinical treatments for movement impairments. Such impairments are caused by common conditions such as stroke, osteoarthritis, Parkinson’s disease, spinal cord injury, cerebral palsy, limb amputation, and even cancer. The lack of clinical impact is somewhat surprising given that comparable computational technology has transformed the design of airplanes, automobiles, and other commercial products over the same time period. This paper provides the author’s personal perspective for how neuromusculoskeletal models can become clinically useful. First, the paper motivates the potential value of neuromusculoskeletal models for clinical treatment design. Next, it highlights five challenges to achieving clinical utility and provides suggestions for how to overcome them. After that, it describes clinical, technical, collaboration, and practical needs that must be addressed for neuromusculoskeletal models to fulfill their clinical potential, along with recommendations for meeting them. Finally, it discusses how more complex modeling and experimental methods could enhance neuromusculoskeletal model fidelity, personalization, and utilization. The author hopes that these ideas will provide a conceptual blueprint that will help the neuromusculoskeletal modeling research community work toward clinical utility.

Long-term outcome of iliosacral resection without reconstruction for primary bone tumours

AIMS

Iliac wing (Type I) and iliosacral (Type I/IV) pelvic resections for a primary bone tumour create a large segmental defect in the pelvic ring. The management of this defect is controversial as the surgeon may choose to reconstruct it or not. When no reconstruction is undertaken, the residual ilium collapses back onto the remaining sacrum forming an iliosacral pseudarthrosis. The aim of this study was to evaluate the long-term oncological outcome, complications, and functional outcome after pelvic resection without reconstruction.

METHODS

Between 1989 and 2015, 32 patients underwent a Type I or Type I/IV pelvic resection without reconstruction for a primary bone tumour. There were 21 men and 11 women with a mean age of 35 years (15 to 85). The most common diagnosis was chondrosarcoma (50%, n = 16). Local recurrence-free, metastasis-free, and overall survival were assessed using the Kaplan-Meier method. Patient function was evaluated using the Musculoskeletal Tumour Society (MSTS) and Toronto Extremity Salvage Score (TESS).

RESULTS

At a mean follow-up of 159 months (1 to 207), 23 patients were alive without disease, one was alive with lung metastases, one was alive following local recurrence, four were dead of disease, and three had died from other causes. The overall ten-year survival was 77%. There was only one (3%) local recurrence, which occurred at 26 months. There were 18 complications in 17 patients; 13 wound healing complications/infections, three fractures, one pulmonary embolism, and one dislocation of the hip. Most complications occurred early. The mean functional scores were 21.1 (SD 8.1) for MSTS-87, 67.3 (SD 23.9) for MSTS-93 and 76.2 (SD 20.6) for TESS.

CONCLUSION

Patients requiring Type I or Type I/IV pelvic resections can expect a good oncological outcome and a high rate of local control. Complications are generally acute in nature and are easily manageable. These patients achieved a good functional outcome without the need for bony reconstruction. Cite this article: Bone Joint J 2020;102-B(6):779-787.

COMPLICATIONS AND COST ANALYSIS OF HEMIPELVECTOMY FOR THE TREATMENT OF PELVIC TUMORS

Objective:

Hemipelvectomy is a complex surgery with a high complication rate. Here, we aimed to identify factors related to the onset of complications and calculate their impacts on hospital costs.

Methods:

We evaluated 31 consecutive patients who underwent hemipelvectomy between 1999 and 2015. We assessed the clinical and radiographic data to determine the patients’ demographic factors, tumor and surgical characteristics, and complications. The individual hospital stays and financial balances were assessed up to 6 months following the index surgery.

Results:

The overall complication rate was 61% (19/31). Infection was the most prevalent complication (36%). Immediate postoperative death occurred in 5/31 patients (16%); another 5 (16%) died after hospital discharge due to disease progression. Histological grade, previous surgery, and previous radiotherapy were not associated with complications or infection. Acetabular resections, bone reconstruction, and longer operative times were associated with infection, whereas older age, pelvic organ involvement, and comorbidities were associated with immediate postoperative death. Complications and infection were associated with 4.8- and 5.9-fold increases in hospital costs, respectively.

Conclusions:

Acetabular resection and bone reconstruction are important factors that increase short-term complication rates, infection rates, and hospital costs. Mortality was associated with older age and adjacent pelvic tumor progression. Level of Evidence: IV, case series.

Resection and reconstruction of pelvic bone tumors

The objective of this study was to assess outcome and recurrence rate after limb-salvage surgery with reconstruction for pelvic bone tumors and analyze complications and their relationship with surgery. The authors analyzed 129 patients followed for a mean of 6 years (range, 2-19 years). Chondrosarcoma was the most frequent histotype. Thirty-one cases with no acetabular involvement were reconstructed with allograft only. Acetabular resections were reconstructed with allograft prosthetic composite (n=60), allograft only (n=11), trabecular metal components (n=2), prosthesis only (n=10), saddle prosthesis (n=11), and iliofemoral arthrodesis (n=1). Margins were wide (n=94), wide contaminated (n=22), marginal (n=7), and intralesional (n=6). Oncologic outcomes were as follows: 75 patients were continuously disease free, 6 were disease free after treatment of relapse, 13 were alive with disease, 28 were dead of disease, and 5 were dead of other causes. Survival was 66% at 10 years. Local recurrence rate of malignant tumors was 22.1% and was not statistically influenced by margins (P=.140) or site (P=.933). Metastasis rate was 32.8%. Deep infection was observed in 30 (23.6%) cases, with no statistical difference between reconstructions with and without allograft (P=.09). Final external hemipelvectomy was performed in 16 cases. Newer techniques of reconstruction using stemmed acetabular cups or porous metal components combined with allograft are now available. Local control and satisfactory survival is achievable long term in patients with pelvic tumors, but this surgery implies a high rate of complications. Infection is a major complication, not influenced by the use of allografts. Amputation is rarely needed.

Alloprosthetic composite is a suitable reconstruction after periacetabular tumor resection

BACKGROUND

Resection of a tumor of the pelvis is most disabling when the acetabulum is excised and a durable reconstruction of the defect is hard to achieve. All available methods are associated with frequent complications. Few large series have been published, and fewer have focused entirely on complete resections of the acetabulum. The use of an allograft-prosthetic composite allows customization on the operating table. However, while such composites restore anatomy and function of the pelvis the use of pelvic allografts is controversial and the durability is unknown.

QUESTIONS/PURPOSES

We therefore examined (1) the frequency of allograft and prosthetic failure, (2) positive and negative factors influencing the survival of the allograft prosthetic composite, and (3) function of patients with this reconstruction.

PATIENTS AND METHODS

We retrospectively evaluated 35 patients who had resection of the entire acetabulum and reconstruction with an allograft-prosthetic composite. Function was scored by the Musculoskeletal Tumor Society system. Followup in 24 survivors averaged 120 months (range, 61-188 months).

RESULTS

Greater than 75% of the allografts were still in place at last followup, and the original prosthetic reconstruction was still in place in 56%. Infection was an important negative factor for allograft survival. The average functional score was 72%, with better mean scores for patients who had reconstruction with a stemmed cup and an artificial ligament (average 89%).

CONCLUSIONS

An allograft-prosthetic composite provides a versatile substitution of the pelvis and hip, with functional scores approximately 75% of normal.

Pelvic chondrosarcomas: surgical treatment options

INTRODUCTION

Chondrosarcoma (CS) is a primary malignant bone tumor with cartilaginous differentiation. The only available treatment is carcinological surgical resection since the usual adjuvant treatments are ineffective. The pelvic location creates specific technical difficulties both for exeresis and reconstruction. Our objective was to evaluate the carcinological and functional outcomes of inter-ilioabdominal amputation and conservative surgery.

MATERIALS AND METHODS

We retrospectively studied 59 cases of pelvis chondrosarcoma managed in our department between 1968 and 2003. Demographic, anatomopathological, surgical and survival data were analyzed. Survival was estimated by the Kaplan-Meier curves and the cumulative incidence method. Multivariate analysis was used to identify all possible independent prognostic variables.

RESULTS

There were 33 men and 26 women, with an average age of 48 years. The average follow-up duration was 94 months. Eleven patients had a grade 1 chondrosarcoma, 36 a grade 2 chondrosarcoma, five were grade 3, and seven were dedifferentiated chondrosarcoma. Eleven patients underwent an inter-ilioabdominal disarticulation, and 48 had a more conservative surgery. Resection margins proved healthy in 46 patients (78%). Eighteen patients (31%) had a local recurrence, and 12 (20%) had metastases. At last follow-up, 30 patients (51%) were still alive without any sign of recurrence. Twenty-three patients (39%) died from the disease. Multivariate analysis showed that margin invasion was associated with a definitely increased local recurrence rate. A high tumoral grade was correlated with a greater risk of metastases occurrence. These two last factors (margin status and tumor grade) as well as acetabulum involvement were correlated with a reduced survival rate. Function was better among patients treated by conservative surgery, and among them, even better when the peri-acetabular area remained intact. Our study confirmed that resection margins quality is a major prognostic factor both for local control and for survival. On the other hand, local recurrence is an adverse survival prognosis factor and is itself correlated with resection margins quality. Peri-acetabular chondrosarcoma location (in zone 2) appears to be a poor oncological prognosis factor since, in this location, obtaining healthy margins appears particularly difficult. Compared to resection, inter-ilioabdominal amputation did not prove its superiority concerning resection margins quality or survival. However, resection guaranteed a better functional outcome.

CONCLUSION

Chondrosarcoma of the pelvic girdle remains of worse prognosis than peripheral bones chondrosarcoma since the critical prognosis factor is the resection margins quality. This location, and especially the peri-acetabular zone, poses difficult specific technical problems when conservative surgery is selected. Various imaging techniques should help better envision tumor resection extent. Inter-ilioabdominal amputation should only be resorted to in non-metastatic patients, when the tumor does not seem to be removable with sufficient healthy margins guarantee, or when local conditions make it impossible to hope for a good quality reconstruction.

LEVEL OF EVIDENCE

Level IV; therapeutic retrospective study.

Revision of the deficient proximal femur with a proximal femoral allograft

Substantial bone loss is frequently encountered with revision hip arthroplasty. A proximal femoral allograft may be used to reconstitute bone stock in the multiply revised femur with segmental bone loss of greater than 5 cm. We retrospectively reviewed 92 patients (93 hips) who underwent such proximal femoral allografts. The average age at the surgery was 61 years. The average number of previous revision procedures was 2.5. Six patients were lost to followup. Thirty-four of 36 deceased patients had the original proximal femoral allograft at the time of death. The minimum followup for the 50 remaining patients was 15 years (average, 16.2 years; range, 15-22 years). Analysis included survivorship and radiographic assessment. Of the 50 patients reviewed, two had a failed reconstruction due to infection, six for aseptic loosening, three for nonunion, and four for dislocation. Revision of the proximal femoral allograft for all reasons excluding the acetabulum was performed in seven patients. At last followup, 42 patients (84%) had a well-functioning construct. Proximal femoral allograft for revision hip arthroplasty in femoral segmental bone loss is a durable alternative in most patients for a complex problem.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.