Extended distal femur resection: Megaprosthesis with telescopic bone allograft augmentation versus total femur prosthesis.

BACKGROUND AND OBJECTIVE: Oncological distal femur resections can leave a proximal femur too short to host a stem. Reconstructive techniques are then challenging. The purpose of the study is to compare implant survival, complication rate and MSTS of two different options. METHODS: We retrospectively divided 33 patients with primary bone tumours of distal femur in Group 1 (16 patients reconstructed with knee megaprosthesis with proximal bone augmentation, APC) and Group 2 (17 patients reconstructed with total femur prosthesis, TFP). Less than 12 cm of remaining proximal femur were planned for all resections. RESULTS: MSTS score at 2 years is 25 ± 5 for Group 1 and 19 ± 7 for Group 2 (confidence interval [C.I.] 95%, p = 0.02). At 5 years it is 27 ± 2 for Group 1 and 22 ± 6 for Group 2 (C.I. 95%, p = 0.047). Failure and complication rates are lower for Group 1, but no statistical significance was reached. In APC reconstruction, union at the host-allograft junction was achieved in 16 out of 16 patients using the telescopic bone augmentation technique. CONCLUSIONS: APC provides higher functional results compared to TFP after extended distal femur resection. In APC reconstruction, telescopic augmentation is excellent for achieving union at the host-allograft junction.

Malawer type I/V proximal humerus reconstruction after tumor resection: a systematic review.

BACKGROUND: Several reconstruction methods exist for Malawer type I/V proximal humerus reconstruction after bone tumor resection; however, no consensus has been reached regarding the preferred methods. METHODS: We conducted a literature search on various types of proximal humerus oncologic reconstruction methods. We collected data on postoperative functional outcomes assessed based on Musculoskeletal Tumor Society (MSTS) scores, 5-year reconstruction survival rates, and complications. We calculated each reconstruction's weighted mean based on the sample size and standard errors. Complications were categorized based on the Henderson classification. Based on these integrated data, our primary objective is to propose an optimal strategy for proximal humerus reconstruction after bone tumor resection. RESULTS: We examined various reconstruction techniques, including modular prosthesis (752 patients in 21 articles), osteoarticular allograft (142 patients in 6 articles), allograft prosthesis composites (APCs) (236 patients in 12 articles), reverse shoulder total arthroplasty (141 patients in 10 articles), composite reverse shoulder total arthroplasty (33 patients in 4 articles), claviculo-pro-humero (CPH) technique (51 patients in 6 articles), and cement spacer (207 patients in 4 articles). Weighted mean MSTS scores were: modular prosthesis (73.8%), osteoarticular allograft (74.4%), APCs (79.2%), reverse shoulder total arthroplasty (77.0%), composite reverse shoulder total arthroplasty (76.1%), CPH technique (75.1%), and cement spacer (69.1%). Weighted 5-year reconstruction survival rates were modular prosthesis (85.4%), osteoarticular allograft (67.6%), APCs (85.2%), reverse shoulder total arthroplasty (84.1%), and cement spacer (88.0%). Reconstruction survival data was unavailable for composite reverse shoulder total arthroplasty and CPH technique. Major complications included shoulder joint instability: modular prosthesis (26.2%), osteoarticular allograft (41.5%), APCs (33.9%), reverse shoulder total arthroplasty (17%), composite reverse shoulder total arthroplasty (6.1%), CPH technique (2.0%), and cement spacer (8.7%). Aseptic loosening of the prosthesis occurred: modular prosthesis (3.9%) and reverse shoulder total arthroplasty (5.7%). Allograft fracture was observed in 54.9% of patients with osteoarticular allograft. CONCLUSION: The complication profiles differed among reconstruction methods. Weighted mean MSTS scores exceeded 70% in all methods except cement spacer, and the 5-year reconstruction survival rate surpassed 80% for all methods except osteoarticular allograft. Proximal humerus reconstruction after bone tumor resection should consider potential complications and patients' individual factors.

Management of proximal humerus bone loss with allograft prosthetic composite technique in shoulder arthroplasty.

BACKGROUND: Proximal humerus bone loss in shoulder arthroplasty is a difficult problem with limited treatment options. It most commonly occurs in the setting of a previously failed shoulder arthroplasty; however, it is occasionally encountered in cases of primary shoulder arthroplasty. Reconstruction of the proximal humerus is essential for soft tissue tension for implant stability and maximizing function. The purpose of this study was to analyze the clinical and functional outcomes of the allograft prosthetic composite (APC) technique for the management of proximal humeral bone loss in shoulder arthroplasty. METHODS: A retrospective review was performed of all patients who underwent primary or revision shoulder arthroplasty using an APC technique with a reverse shoulder arthroplasty prosthesis for the management of proximal humerus bone loss. Data collected included demographic variables, previous shoulder surgeries, indication for APC, type of allograft utilized, fixation technique, and reoperation and revision rates. Patients were contacted by phone and/or email survey to obtain the latest patient-reported functional outcome scores. RESULTS: We identified 14 patients who underwent shoulder arthroplasty using the APC technique with a reverse shoulder arthroplasty prosthesis. One (7.1%) was performed as a primary arthroplasty, and 13 (92.9%) were performed as revision arthroplasties. The indications for APC were instability (21.4%), periprosthetic fracture (21.4%), periprosthetic joint infection (14.3%), humeral component loosening (14.3%), rotator cuff failure (14.3%), fracture sequelae (7.1%), and failed hemiarthroplasty (7.1%). In terms of allograft type, 10 (71.4%) were performed with proximal femur allograft and 4 (28.6%) with proximal humerus allograft. There were 6 patients (42.9%) who sustained postoperative complications, 5 patients (35.7%) had instability, and 1 (7.1%) patient had postoperative wound drainage. All patients with a complication required a revision arthroplasty. CONCLUSION: The APC technique used to address proximal humerus bone loss in shoulder arthroplasty has a high complication rate with fair patient-reported functional outcome scores. Most of the postoperative complications and reoperations are related to implant instability.

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.

Comparison of reconstructive techniques following oncologic intraarticular resection of proximal humerus.

INTRODUCTION: The proximal humerus is a common site of primary and metastatic disease in the upper extremity. Historically, the goal of a hemiarthroplasty reconstruction was to provide a stable platform for hand and elbow function, with limited shoulder function. Techniques utilizing a reverse endoprosthesis (endoprosthetic replacement [EPR]) and allograft-prosthetic composite (APC) have been developed; however, there is a paucity of comparative studies. METHODS: A total of 83 (42 females, 41 males) patients undergoing an intraarticular resection of the humerus were reviewed. Reconstructions included 30 reverse and 53 hemiarthroplasty; including hemiarthroplasty EPR (n = 36) and APC (n = 17), and reverse EPR (n = 20) and APC (n = 10). RESULTS: Reverse reconstructions had improved forward elevation (85° vs. 44°, p < .001) and external rotation (30° vs. 21°; p < .001) versus a hemiarthroplasty. Reverse reconstructions had improved American Shoulder and Elbow Surgeons scores (65 vs. 57; p = .01) and Musculoskeletal Tumor Society 93 scores (72 vs. 63; p < .001) versus hemiarthroplasty. Subluxation of the reconstruction was a common (n = 23, 27%), only occurring in hemiarthroplasty patients (EPR [n = 13, 36%] and APC [n = 10, 59%]). CONCLUSION: The current series highlights the improved functional outcome in patients undergoing reconstruction with a reverse arthroplasty compared to the traditional hemiarthroplasty. Currently reverse shoulder arthroplasty (APC or EPR) is our preferred methods of reconstruction in this patient population.

Successful mid- to long-term outcome after reconstruction of the extensor apparatus using proximal tibia-patellar tendon composite allograft.

PURPOSE: The purpose of the study was to assess the outcomes of extensor mechanism reconstruction with proximal tibia-patellar tendon composite allograft. METHODS: 24 consecutive patients treated with allograft-prosthetic composite for proximal tibia tumour resection and a conventional total knee arthroplasty were included. Extensor mechanism reconstruction was performed with a proximal tibia-patellar tendon composite allograft and the suture of the donor tendon to the remnant native patellar tendon. Function was evaluated by the Musculoskeletal Tumor Society score (MSTS) and range of motion. Western Ontario and MacMaster University (WOMAC) and visual analogue scale for pain also were used. RESULTS: After a mean follow-up of 11.7 (range 3-15) years, mean MSTS score was 22.4 (range 20-30), mean flexion was 94.0° (range 84°-110°), and mean extension lag was 7.2° (range 0°-18°). The mean VAS-pain was 4.3 (range 2-6), and WOMAC score was 72.4 (range 58-100). There was no failure of the reconstructed extensor mechanism. CONCLUSION: Patellar tendon reconstruction with allogeneic tissue from the proximal tibia allograft sutured to the recipient's remnant patellar tendon provides the mechanical support needed for healing of the reconstructed extensor mechanism with a substantial functional benefit to stabilize active knee extension and successful reconstruction survival at long-term. LEVEL OF EVIDENCE: III.

Resurfaced allograft-prosthetic composite for distal femur reconstruction in children with bone tumor.

INTRODUCTION: Reconstruction of the distal femur in children following resection of bone sarcoma is challenging. The main problem in children is the small size of bone and a possible limb-length discrepancy at the end of skeletal growth secondary to the loss of the physes. We reported the results of a new surgical technique for distal femur reconstruction after bone tumor resection in children. MATERIAL AND METHODS: We analyzed 5 patients with distal femoral sarcomas who underwent intra-articular resection and reconstruction with resurfaced allograft-prosthetic composite at a mean follow-up of 70 months. There were 2 males and 3 females, with a mean age of 10 years (range 8-12) at the time of the diagnosis. All patients were affected by high-grade osteosarcoma. The patients' medical records were reviewed for clinical and functional outcomes as well as post-operative complications. The functional evaluation of the patients was done at the end of the follow-up using Musculoskeletal Tumor Society scoring system. The minimal follow-up was 24 months. RESULTS: At the last follow-up, 4 patients were continuously disease-free. We excluded one patient who died of disease secondary to lung metastases 16 months after the surgery. Complications occurred in 2 of 4 patients at 17 months and 24 months, respectively. One patient developed deep infection who required the removal of the original reconstruction and, once the infection was treated, the patient underwent reconstruction with an expandable prosthesis. An allograft fracture occurred in another of the 4 patients at 24 months after the first surgery, thus the original reconstruction was removed and the patient underwent reconstruction with modular prosthesis. In the two patients who retained the original reconstruction at the time of their latest follow-up, the mean implant survival time was 70 months. These patients had an excellent MSTS score (29.5 points) and walked without support or limitations with an active knee range of motion of > 90° and complete active extension of the knee. No degenerative changes of the articular surface of the proximal tibia and the patella were observed at the time of the last follow-up. Growth of the physis of the proximal tibia was observed in all the patients during follow-up and no angular deformity of the joint was observed. The limb discrepancy was 4 cm and 2 cm, respectively. CONCLUSIONS: Resurfaced allograft-prosthetic composite may represent an alternative surgical technique for distal femur reconstruction in children with bone sarcomas. Although its success is limited by high risk of complications, resurfaced allograft-prosthetic composite seems to be a viable option to preserve the bone stock and the physis of the proximal tibia in selected young patients, minimizing a potential limb-length discrepancy at the end of the skeletal growth.

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

BACKGROUND: Allograft-prosthetic composite (APC) reconstruction of the proximal humerus is a technique for reconstruction of large bone deficits, provides improvement in pain and function, and is thought to restore bone if revision surgery is needed. The purpose of this study was to evaluate the ability of proximal humeral APCs to restore usable bone at the time of revision surgery. METHODS: Two institutional electronic medical records were reviewed to evaluate proximal humeral APC procedures performed between 1970 and 2018. We identified 115 cases, of which 14 underwent revision for aseptic causes. The indications for revision included nonunion (n = 7), glenohumeral instability (n = 5), and allograft fracture (n = 2). Three categories were used to classify the amount of usable allograft retained at revision surgery: type A, complete allograft retention; type B, partial retention; and type C, no retention. RESULTS: A total of 14 patients (6 male and 8 female patients) underwent revision of the APC reconstruction at a mean of 22.8 months. At revision, allograft retention was classified as type A in 6 shoulders, type B in 3, and type C in 5. Type A cases were associated with nonunion with a well-fixed stem, type B cases were associated with instability and were converted from a hemiarthroplasty to a reverse total shoulder arthroplasty, and type C cases were associated with an allograft fracture or nonunion with a loose humeral component. CONCLUSION: A substantial number of revisions of proximal humeral APC reconstructions maintain a portion of the allograft bone (64.3%). This study supports the ongoing use of the APC reconstruction technique for large bone deficits.

[Therapeutic Effect of Uncemented Allograft-prosthetic Composite for the Reconstruction of Tumorous Bone Defect].

OBJECTIVE: To investigate the surgical techniques and mid-term efficacy of reconstruction for proximal femur with allograft-prosthetic composite (APC) . METHODS: Fifteen patients who underwent uncemented APC reconstruction of proximal femur after bone tumor resection were retrospectively evaluated. Image and physical examinations were taken on the 1st,3rd,6th,9th and 12th month after surgery and every 6 months thereafter to assess union condition,greater trochanteric bone absorption and myodynamia of abductors. Musculoskeletal Tumor Society (MSTS) and Harris Hip Score (HHS) were utilized to evaluate the function of hip joint. RESULTS: Seven male and eight female patients were included with average age of 25.1 years(17-56 years) and average followup of 32.8 months(18-48 months). Four patients had giant cell tumor of the bone,3 patients had osteosarcoma,3 patients had chondrosarcoma,2 patients had malignant fibrous histiotoma,2 patients had osteoblastoma and 1 patient had Ewing sarcoma. Unions occurred in the allograft-host bone interfaces of all patients in the period of 5-9 months postoperatively. Bone absorption in the allograft-host bone interfaces,dislocation,hypersensitivity of the allograft and acetabulum abrasion were not observed,while there were no metastasis and tumor recurrence. Three patients had periprosthetic fractures intraoperatively and were well fixed with cerclage. Absorptions in the greater trochanteric happened to 6 patients. All patients had mean MSTS and HHS scores of 11.3 (7-15) and 47.3 (40.3-58.5) preoperatively and 26.1(24-29) and 80.1(66.2-92.7) postoperatively. CONCLUSION: Uncemented APC reconstruction is proper for young patients with long life expectancy and high demand of function that suffered from tumors of proximal femur.

Freeze Dried Proximal Femoral Allografts in Revision of Femoral Stems.

BACKGROUND: Femoral bone deficiency is a challenging problem in revision femoral arthroplasty in younger patients. We evaluated outcomes of revision femoral arthroplasty using a freeze-dried allograft prosthetic composite (APC). METHODS: This was a retrospective review of 16 patients (12 men and 4 women) who had unilateral proximal femoral deficiencies (Paprosky type III B, 13 patients; type IV, 3 patients) revised with freeze-dried APC. Follow-up at mean 7 years included assessment with Merle D'Aubigné score and radiographs. RESULTS: At follow-up, the average hip score was improved for pain, function, and range of motion. The 5-year graft survival was 87%, and the estimated median survival was 8.8 years. There were 3 patients who walked without support, 10 patients who walked unlimited distance with a cane, 2 patients who walked with 2 crutches, and 1 patient who walked with a walker. Radiographs showed nonunion at the graft-host junction in 3 hips (19%), but only 1 patient was symptomatic. Asymptomatic trochanteric nonunion was observed in 4 hips (25%). There was moderate graft resorption in 2 patients at 9 years after surgery and mild graft resorption in 1 graft at 7 years. There was subsidence of <2 cm in 2 patients and 3.5 cm in 1 patient. CONCLUSION: The present study showed acceptable results in treatment of major femoral deficiencies using freeze-dried APC in younger patients. Freeze-dried APC may be a useful for revision femoral arthroplasty.

Allograft-prosthetic composite reverse total shoulder arthroplasty for reconstruction of proximal humerus tumor resections.

BACKGROUND: Proximal humerus reconstructions after resection of tumors are challenging. Early success of the reverse shoulder arthroplasty for reconstructions has recently been reported. The reverse allograft-prosthetic composite offers the advantage of improved glenohumeral stability compared with hemiarthroplasty for proximal humeral reconstructions as it uses the deltoid for stability. METHODS: This article describes the technique for treating proximal humeral tumors, including preoperative planning, biopsy principles, resection pearls, soft tissue tensioning, and specifics about reconstruction using the reverse allograft-prosthetic composite. Two cases are presented along with the functional outcomes with use of this technique. Biomechanical considerations during reconstruction are reviewed, including techniques to improve the deltoid compression force. RESULTS: Reported instability rates are less with reverse shoulder arthroplasty reconstruction as opposed to hemiarthroplasty or total shoulder arthroplasty reconstructions of tumor resections. Reported functional outcomes are promising for the reverse allograft-prosthetic composite reconstructions, although complications are reported. CONCLUSION: Reverse allograft-prosthetic composites are a promising option for proximal humeral reconstructions, although nonunion of the allograft-host bone junction continues to be a challenge for this technique.

Tendon transfers in the setting of shoulder arthroplasty.

Background: Tendon transfers in conjunction with reverse total shoulder arthroplasty can significantly improve functional outcomes in patients with glenohumeral arthritis and irreparable rotator cuff deficiency. There have been multiple promising new techniques described within the last 20 years that shoulder surgeons should become familiar with. Methods: The authors reviewed the literature on tendon transfers in the setting of reverse total shoulder arthroplasty. Procedures to restore various shoulder functions were described including surgical anatomy, techniques, pearls and pitfalls, and photos. Results: Subscapularis insufficiency can be reconstructed with a pectoralis major transfer or latissimus dorsi transfer, with the latter having better clinical outcomes and a more anatomic line of pull. Posterosuperior rotator cuff deficiency can be reconstructed with a latissimus transfer (L'Episcopo transfer) or lower trapezius transfer, with the latter proving superior in biomechanical and short-term studies. Deltoid deficiency can be reconstructed with a pedicled upper pectoralis major transfer. Massive proximal humerus bone loss can be reconstructed with an allograft-prosthetic composite, and any of the aforementioned transfers can be utilized in this setting as well. Conclusion: Tendon transfers in conjunction with reverse shoulder arthroplasty can significantly improve functional outcomes in patients with glenohumeral arthritis and irreparable rotator cuff deficiency. There have been multiple promising new techniques described within the last 20 years that shoulder surgeons should become familiar with.

Extended deltopectoral approach for revision total elbow arthroplasty requiring humeral allograft-prosthetic composites in patients with severely compromised proximal humerus bone stock.

Background: Severe humeral bone loss in the setting of failed total elbow arthroplasty (TEA) poses a particularly challenging reconstructive problem. The objective of this study was to review the rationale, indications, contraindications, and detailed surgical technique for using an extended anterior deltopectoral approach to perform a revision TEA when substantially long allografts are required in the presence of severely compromised proximal humerus bone stock. Methods: The authors developed this exposure and reconstructive strategy for failed elbow arthroplasties where the remaining segment of proximal humerus is extremely short, which makes adequate plate fixation of an allograft-prosthetic composite (APC) to the native bone extremely challenging. From an anterior deltopectoral approach, it is possible to use dedicated long, precontoured proximal humerus locking plates to maximize fixation in any remaining proximal humerus. This exposure still makes it possible to provide adequate access to the coupling mechanism of the humeral and ulnar components for implantation of a linked elbow arthroplasty. This exposure also allows for adequate judgment of humeral length and rotation. Pitfalls and Challenges: Crucial steps in the surgery include extending the dissection past the elbow flexion crease such that one can obtain circumferential exposure of the distal humerus. It is also important to couple the humeral and ulnar components prior to committing to the length of the APC. Special attention must be paid to gauge appropriate APC rotation and length for proper soft tissue tension. When performing fixation of the proximal humeral plate, screw purchase must be maximized in both the remaining native proximal humerus and the APC. Compression across the allograft-host interface is paramount for healing to occur. Conclusion: An extended anterior deltopectoral approach to perform a revision TEA when very long APCs are required is a viable option to restore humeral bone stock and regain humeral stem fixation in the setting of failed TEA with extensive humeral bone loss.

Midterm outcomes allograft prosthetic composite reconstruction for massive bone loss at the elbow.

BACKGROUND: Revision of a loose total elbow arthroplasty (TEA) is challenging, particularly in the context of massive bone loss (MBL). The use of an allograft prosthetic composite (APC) at the elbow is rare, typically reserved as a salvage procedure for MBL. Thus, limited data describing the outcomes of APCs are available in current literature. HYPOTHESIS: The authors hypothesize that short to midterm clinical outcomes of APC for MBL about the elbow are satisfactory. PATIENTS AND METHODS: Between 2009 and 2018, 6 APCs implanted with a semi-constrained Coonrad Morrey prosthesis were performed in 5 females and 1 male. Median patient age was 70 years (range, 49-76 years). The indication for revision was aseptic loosening in all 6 cases (6 humeral and 2 ulnar). Median follow-up was 3.5 years (range, 2-6.7 years). Functional outcomes including Mayo Elbow Performance Score (MEPS), Visual Analog Scale (VAS), range of motion (ROM), and radiographic outcomes were assessed for all patients. RESULTS: Median MEPS and VAS scores were 75 (range, 40-90), and 0 (range, 0-8) at latest follow-up, respectively. Median postoperative flexion-extension and prono-supination arcs were 90̊ (range, 70-140̊) and 150 (range, 100-160̊), respectively. Allograft incorporation was noted in 5 (83%) patients; all prostheses were well-fixed. In total, 4 patients (63%) experienced 5 complications (83%) including periprosthetic fracture (n=2), ulnar neuropathy (n=1), aseptic loosening (n=1), and wound dehiscence (n=1). Two (33%) required reoperation with prosthetic retention. CONCLUSION: Elbow reconstruction using allograft prosthetic composite is a viable option for patients with MBL following TEA. The midterm functional outcomes are satisfactory with no revisions required, despite a relatively high rate of complications. Further long-term studies with larger cohorts are needed to better elucidate long-term outcomes and reasons for failure. LEVEL OF EVIDENCE: IV; therapeutic study (case series [no, or historical, control group]).

Megaprosthetic reconstruction of the distal femur with a short residual proximal femur following bone tumor resection: a systematic review.

BACKGROUND: To investigate the risk of postoperative function and complications associated with reconstruction methods in patients with short residual proximal femurs (< 12 cm) after resection of distal femoral bone tumors, we performed a systematic review of studies reporting postoperative function and complications in these patients. METHODS: Of the 236 studies identified by systematic searches using the Medline, Embase, and Cochrane Central Register of Controlled Trials databases, eight were included (none were randomized controlled trials). In these studies, 106 (68.4%), 12 (7.7%), and 37 (23.9%) patients underwent reconstruction with custom-made megaprostheses with extracortical plates or cross-pins, allograft prosthetic composite (APC), and Compress® compliant pre-stress (CPS) implants, respectively. RESULTS: Aseptic loosening occurred slightly more frequently in the APC group than in the other reconstruction methods (APC group, 21%; custom-made megaprosthesis group, 0-17%; CPS implant group, 14%). No differences were noted in the frequencies of implant breakage, fractures, or infections between the three reconstruction methods. Mechanical survival, where endpoint was set as implant removal for any reason, was 80% at seven years in the APC group, 70-77% at 10 years in the custom-made megaprosthesis group, and 68% at nine years in the CPS implant group. Therefore, there appeared to be no difference among the three reconstruction methods with respect to mechanical survival. CONCLUSIONS: During megaprosthetic reconstruction of the distal femur with a short residual proximal femur after bone tumor resection, similar results were obtained using custom-made megaprostheses, APCs, and CPS implants.

Megaprosthesis versus Allograft Prosthesis Composite for massive skeletal defects.

Massive skeletal defects are encountered in the setting of tumors necessitating excision, failed total hip arthroplasty with periprosthetic bone loss, periprosthetic fracture, complex trauma, multiple failed osteosynthesis and infection. Reconstruction of the segmental defects poses a tremendous challenge to the orthopaedic surgeons. The goal of osseous reconstruction of these defects is to restore the bone length and function. Currently the most commonly employed methods for reconstruction are either a megaprosthesis or an Allograft Prosthesis Composite (APC). Megaprosthesis, initially created for the treatment in neoplastic pathologies are being used for the non-neoplastic pathologies as well. The longevity of these implants is an issue as majority of the patients receiving them are the survivors of oncologic issue or elderly population, both in which the life expectancy is limited. However, the early complications like instability, infection, prosthetic breakage and fixation failure have been extensively reported in several literatures. Moreover, the megaprostheses are non-biological options preventing secure fixation of the soft tissue around the implant. The Allograft Prosthesis Composites were introduced to overcome the complications of megaprosthesis. APC is made of a revision-type prosthesis cemented into the skeletal allograft to which the remaining soft tissue sleeve can be biologically fixed. APCs are preferred in young and low risk patients. Though the incidence of instability is relatively low with the composites as compared to the megaprosthesis, apart from infection, the newer complications pertaining to APCs are inevitable that includes non-union, allograft resorption, periprosthetic fracture and potential risk of disease transmission. The current review aims to give an overview on the treatment outcomes, complications and survival of both the megaprostheses and APCs at different anatomic sites in both the upper and lower limbs.

Reconstruction After Tumor Resection in the Growing Child.

Limb preservation surgery has gained acceptance as a viable alternative to amputation for the treatment of extremity bone tumors in the growing child. There are several options for reconstructing the potential loss of a physis and the defect created by tumor excision. Metallic endoprosthesis, massive allograft, and allograft-prosthesis composites have been described in the skeletally immature population. With the development of expandable prostheses, even those far from skeletal maturity may be candidates for limb salvage. However, improvements in the literature are needed, including reporting surgical and functional outcomes in a rigorous manner, specific to age, anatomic location, and reconstruction.

Uncemented allograft-prosthetic composite reconstruction of the proximal femur.

BACKGROUND: Allograft-prosthetic composite can be divided into three groups names cemented, uncemented, and partially cemented. Previous studies have mainly reported outcomes in cemented and partially cemented allograft-prosthetic composites, but have rarely focused on the uncemented allograft-prosthetic composites. The objectives of our study were to describe a surgical technique for using proximal femoral uncemented allograft-prosthetic composite and to present the radiographic and clinical results. MATERIALS AND METHODS: Twelve patients who underwent uncemented allograft-prosthetic composite reconstruction of the proximal femur after bone tumor resection were retrospectively evaluated at an average followup of 24.0 months. Clinical records and radiographs were evaluated. RESULTS: In our series, union occurred in all the patients (100%; range 5-9 months). Until the most recent followup, there were no cases with infection, nonunion of the greater trochanter, junctional bone resorption, dislocation, allergic reaction, wear of acetabulum socket, recurrence, and metastasis. But there were three periprosthetic fractures which were fixed using cerclage wire during surgery. Five cases had bone resorption in and around the greater trochanter. The average Musculoskeletal Tumor Society (MSTS) score and Harris hip score (HHS) were 26.2 points (range 24-29 points) and 80.6 points (range 66.2-92.7 points), respectively. CONCLUSIONS: These results showed that uncemented allograft-prosthetic composite could promote bone union through compression at the host-allograft junction and is a good choice for proximal femoral resection. Although this technology has its own merits, long term outcomes are yet not validated.