Revision of the deficient proximal femur with a proximal femoral allograft

Does Freehand, Patient-specific Instrumentation or Surgical Navigation Perform Better for Allograft Reconstruction After Tumor Resection? A Preclinical Synthetic Bone Study

BACKGROUND

Joint-sparing resection of periarticular bone tumors can be challenging because of complex geometry. Successful reconstruction of periarticular bone defects after tumor resection is often performed with structural allografts to allow for joint preservation. However, achieving a size-matched allograft to fill the defect can be challenging because allograft sizes vary, they do not always match a patient's anatomy, and cutting the allograft to perfectly fit the defect is demanding.

QUESTIONS/PURPOSES

(1) Is there a difference in mental workload among the freehand, patient-specific instrumentation, and surgical navigation approaches? (2) Is there a difference in conformance (quantitative measure of deviation from the ideal bone graft), elapsed time during reconstruction, and qualitative assessment of goodness-of-fit of the allograft reconstruction among the approaches?

METHODS

Seven surgeons used three modalities in the same order (freehand, patient-specific instrumentation, and surgical navigation) to fashion synthetic bone to reconstruct a standardized bone defect. National Aeronautics and Space Administration (NASA) mental task load index questionnaires and procedure time were captured. Cone-beam CT images of the shaped allografts were used to measure conformance (quantitative measure of deviation from the ideal bone graft) to a computer-generated ideal bone graft model. Six additional (senior) surgeons blinded to modality scored the quality of fit of the allografts into the standardized tumor defect using a 10-point Likert scale. We measured conformance using the root-mean-square metric in mm and used ANOVA for multipaired comparisons (p < 0.05 was significant).

RESULTS

There was no difference in mental NASA total task load scores among the freehand, patient-specific instrumentation, and surgical navigation techniques. We found no difference in conformance root-mean-square values (mean ± SD) between surgical navigation (2 ± 0 mm; mean values have been rounded to whole numbers) and patient-specific instrumentation (2 ± 1 mm), but both showed a small improvement compared with the freehand approach (3 ± 1 mm). For freehand versus surgical navigation, the mean difference was 1 mm (95% confidence interval [CI] 0.5 to 1.1; p = 0.01). For freehand versus patient-specific instrumentation, the mean difference was 1 mm (95% CI -0.1 to 0.9; p = 0.02). For patient-specific instrumentation versus surgical navigation, the mean difference was 0 mm (95% CI -0.5 to 0.2; p = 0.82). In evaluating the goodness of fit of the shaped grafts, we found no clinically important difference between surgical navigation (median [IQR] 7 [6 to 8]) and patient-specific instrumentation (median 6 [5 to 7.8]), although both techniques had higher scores than the freehand technique did (median 3 [2 to 4]). For freehand versus surgical navigation, the difference of medians was 4 (p < 0.001). For freehand versus patient-specific instrumentation, the difference of medians was 3 (p < 0.001). For patient-specific instrumentation versus surgical navigation, the difference of medians was 1 (p = 0.03). The mean ± procedural times for freehand was 16 ± 10 minutes, patient-specific instrumentation was 14 ± 9 minutes, and surgical navigation techniques was 24 ± 8 minutes. We found no differences in procedures times across three shaping modalities (freehand versus patient-specific instrumentation: mean difference 2 minutes [95% CI 0 to 7]; p = 0.92; freehand versus surgical navigation: mean difference 8 minutes [95% CI 0 to 20]; p = 0.23; patient-specific instrumentation versus surgical navigation: mean difference 10 minutes [95% CI 1 to 19]; p = 0.12).

CONCLUSION

Based on surgical simulation to reconstruct a standardized periarticular bone defect after tumor resection, we found a possible small advantage to surgical navigation over patient-specific instrumentation based on qualitative fit, but both techniques provided slightly better conformance of the shaped graft for fit into the standardized post-tumor resection bone defect than the freehand technique did. To determine whether these differences are clinically meaningful requires further study. The surgical navigation system presented here is a product of laboratory research development, and although not ready to be widely deployed for clinical practice, it is currently being used in a research operating room setting for patient care. This new technology is associated with a learning curve, capital costs, and potential risk. The reported preliminary results are based on a preclinical synthetic bone tumor study, which is not as realistic as actual surgical scenarios.

CLINICAL RELEVANCE

Surgical navigation systems are an emerging technology in orthopaedic and reconstruction surgery, and understanding their capabilities and limitations is paramount for clinical practice. Given our preliminary findings in a small cohort study with one scenario of standardized synthetic periarticular bone tumor defects, future investigations should include different surgical scenarios using allograft and cadaveric specimens in a more realistic surgical setting.

Shape-memory sawtooth-arm embracing clamp used in complex femoral revision hip arthroplasty for stem stability: average 9-year follow-up study

BACKGROUND

Nickel-Titanium shape-memory sawtooth-arm embracing clamps (SSECs) have been used in revision total hip arthroplasties (rTHAs) to protect stem stability. This study was to introduce this technique and report its mid to long-term clinical and radiographic outcomes.

METHODS

We retrospectively reviewed all patients implanted with SSECs in our department from January 2008 to December 2015. 41 patients (41 hips) were finally included. Radiographs and Harris hip scores (HHS) were collected. Radiographs were blindly analyzed for evidence of loosening, subsidence and stress shielding. HHS were compared to previous records by student's t tests. The average follow-up period was 9.3 years.

RESULTS

All stems were stably fixed with no signs of loosening. The mean stem subsidence was 0.9 mm (range, 0 to 3 mm). Only one patient (2.4%) demonstrated the fourth degree of stress shielding, with the others none or minor bone resorption. The mean HHS at the final follow-up was 84.2 (range, 81 to 91), which was improved from 17.4 (range, 0 to 37) before surgery. No implant failures or re-revisions occurred. Dislocation occurred in 1 case during the follow-up period.

CONCLUSIONS

The SSEC protected stem fixation and achieved favorable clinical and radiographic outcomes in this 9-year follow-up study. It offered an additional extramedullary fixation option for surgeons to choose from in treating complex femoral revision arthroplasties.

Intussusception Allograft Prosthetic Composites in Total Hip Arthroplasty: A Salvage Operation for Extensive Femoral Bone Loss

BACKGROUND

Allograft prosthetic composites (APCs) have been used to perform revision total hip arthroplasty (THA) for massive femoral bone loss or deformity. Intussusception, or "telescoping", APC techniques have been proposed to enhance the contact area of this interface and provide superior mechanical fixation over conventional methods. The purpose of this study is to present to our knowledge, the largest series of telescoping APC THAs, along with surgical technique details and midterm (average 5-10 years) clinical results.

METHODS

Between 1994 and 2015, 46 revision THAs performed with proximal femoral telescoping APCs were retrospectively reviewed at a single institution. Overall survival, reoperation-free survival, and construct survival rates were calculated via Kaplan-Meier methods. In addition, radiographic analyses were performed to evaluate for component loosening, union at the APC-host interface, and resorption of the allograft.

RESULTS

At 10 years, the overall patient survival was 58%, reoperation-free survival was 76%, and construct survival was 95%. Reoperation was performed in 20% (n = 9) and only 2 constructs required resection. Radiographic analyses performed at latest follow-up revealed no instances of radiographic femoral stem loosening, an 86% union rate at the APC-host site, 23% with signs of some allograft resorption, and a 54% trochanteric union. The mean postoperative Harris hip score was 71 points (range, 46-100).

CONCLUSION

Telescoping APCs are technically demanding, but provide reliable mechanical fixation for the reconstructing of large proximal femoral bone deficits in revision THA with excellent construct survivorship, acceptable reoperation rates, and good clinical outcomes.

LEVEL OF EVIDENCE

IV.

Proximal femoral replacement for non-neoplastic conditions: a systematic review on current outcomes

Proximal femoral replacement (PFR) is a well-established treatment for neoplasia of the proximal femur. The use of this surgical technique for non-neoplastic conditions has increased over the years. We carried out a systematic review of the literature to study the indications, complications, and functional results when PFR is used for non-neoplastic conditions. Twenty-seven studies were included in the review with a total of 828 PFRs with a mean follow-up of 50 months (range 1-225 months). The main indications were infection (28%), periprosthetic fracture (27%), aseptic loosening (22%), and fracture (16%). The rate of reoperation was 20.3% overall. The overall revision rate was 15.4%. The main complications were dislocation (10.2%) and infection (7.3%). After 2010, the rates of reoperation (25.5% versus 18.2%), loosening (9.4% versus 3.2%), and dislocation (15.7% versus 7.9%) were lower than before 2010. The 30-day mortality ranged from 0% to 9%. The hip function scores improved post-surgery. In conclusion, the use of PFR in non-neoplastic conditions remains a marginal tool, associated with low direct mortality and high complication rates, but we expect its use to increase in the near future.

A Novel Endosteal Reconstruction of the Femur from Distal Femoral Remnant Using 3D-Printed Titanium Rings: A Two-Case Report

CASE

Femur reconstruction with only the distal femoral remnant is challenging because of poor bone volume required for stem fixation. Although proximal femoral replacement, total femur replacement, allograft prosthesis composite, and custom porous tantalum implants are options, hybrid fixation enhanced by endosteal reconstruction with three-dimensional (3D)-printed porous titanium rings to reconstruct the femur without supporting isthmus has not been described. We report 2 cases with satisfactory 34- and 22-month follow-up results of hybrid fixation enhanced by endosteal reconstruction with 3D-printed porous titanium rings.

CONCLUSION

This novel method provides a solution to revise loosened femoral endoprosthesis with only distal femoral remnant.

Interlocking reconstruction-mode stem-sideplates preserve at-risk hips with short residual proximal femora

AIMS

We have evaluated the survivorship, outcomes, and failures of an interlocking, reconstruction-mode stem-sideplate implant used to preserve the native hip joint and achieve proximal fixation when there is little residual femur during large endoprosthetic reconstruction of the distal femur.

METHODS

A total of 14 patients underwent primary or revision reconstruction of a large femoral defect with a short remaining proximal femur using an interlocking, reconstruction-mode stem-sideplate for fixation after oncological distal femoral and diaphyseal resections. The implant was attached to a standard endoprosthetic reconstruction system. The implant was attached to a standard endoprosthetic reconstruction system. None of the femoral revisions were amenable to standard cemented or uncemented stem fixation. Patient and disease characteristics, surgical history, final ambulatory status, and Musculoskeletal Tumor Society (MSTS) score were recorded. The percentage of proximal femur remaining was calculated from follow-up radiographs.

RESULTS

All 14 at-risk native hip joints were preserved at a mean final follow-up of 6.0 years (SD 3.7), despite a short residual femur, often after proximal osteotomies through the lesser trochanter. Overall, 13 of 14 stems had long-term successful fixation. Eight patients required no reoperation. Three patients required reoperation due to implant-related issues, and three patients required reoperation for wound healing problems or infection. There were no dislocations or fractures. At final follow-up the mean MSTS score was 24.9 (SD 4.1). Nine patients required no ambulation aids, and only one had a Trendelenburg gait.

CONCLUSION

This interlocking, reconstruction-mode stem-sideplate reliably preserves native hip joint anatomy and function after large femoral resection with a short remaining proximal femur, both in the primary and revision setting. This is particularly important for preventing or delaying total femoral arthroplasty in young patients after oncological reconstruction. Hip abductor strength and function could be maintained by this method, and the risk of dislocation eliminated. The success of this technique in this modest series should be verified in a larger collaborative study and will be of interest to revision surgeons and oncologists. Cite this article: Bone Joint J 2021;103-B(2):398-404.

Proximal Femoral Allograft-Prosthetic Composites: Do They Really Restore Bone? A Retrospective Review of Revision Allograft-Prosthetic Composites

BACKGROUND

Large bone deficiencies are a challenging problem, historically treated with an allograft-prosthetic composite (APC) or megaprosthesis. There were several advantages of the APC compared with early megaprostheses, including the theoretical benefit of restoring bone stock. To our knowledge, there are no studies that have evaluated this claim. Our purpose was to review our institution's experience with APCs of the proximal femur that underwent revision for an aseptic cause and determine if the allograft bone was retained or removed during the revision procedure.

METHODS

We identified 203 proximal femoral allograft prosthetic composites placed from 1988 through 2014. Twenty-seven of these patients underwent a revision because of an aseptic cause. Three categories were devised to classify the amount of allograft retention: type A, complete allograft retention; type B, partial retention; and type C, no allograft retention.

RESULTS

The mean time from the initial APC to revision surgery was 5 years. The most common indication for revision included failure of the allograft (loosening or fracture). At the time of revision, there were 3 type A cases (11%), 4 type B cases (15%), and 20 type C cases (74%). Three of the 4 type B cases used the retained allograft as a strut graft around a newly inserted megaprosthesis.

CONCLUSION

The results of this study are contradictory to previous literature that suggests APCs restore bone stock. In this series, the allograft was retained in only a small percentage of cases when the APC was revised for an aseptic cause.

LEVEL OF EVIDENCE

IV.

Revision total hip arthroplasty - Salvage procedures using bone allografts in Japan

Total hip arthroplasty (THA) and hemiarthroplasty have improved hip joint function of patients suffering from hip disease or trauma with excellent clinical results and long-term survivorship. Conversely, there has been an increase in the number of revision surgeries after THA and hemiarthroplasty due to bone deficiency. The reconstruction of deficient bone remains a challenging problem following THA. While performing revision surgery, we have previously classified the preoperative bone deficiency using X-ray, CT and three-dimensional CT imaging according to location and severity of the deficiencies. We then predicted the shape and amount of the required bone allograft and the type of implant. Due to the accepted reconstruction methods of bone deficiency following revision surgeries, it is important to pre-operatively assess the site and size of the bone deficiency to be repaired in the revision THA (re-THA). Bone allograft makes it possible to repair massive bone deficiency, recover bone stock, and improve long-term implant stability. Performing bone allograft will require a bone bank for harvesting, treating, and storing bone in Japan.

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.

Management of femoral bone loss in revision total hip arthroplasty

Femoral bone loss is frequently encountered during revision total hip arthroplasty. The quality and quantity of remaining bone helps determine the best method for reconstruction. Extensively porous-coated cylindrical stems or titanium fluted tapered devices that achieve fixation in the diaphysis have both demonstrated excellent long-term survivorship. Titanium fluted tapered stems with a modular proximal body allow for more accurate leg length, offset, and version adjustments independent of the distal stem which may optimise hip biomechanics. Intraoperative fractures are more common with cylindrical stems and subsidence with tapered stems, particularly monoblock designs and in both dislocation continues to be one of the most common postoperative complications. In salvage situations in which an ectatic femoral canal is unable to support an uncemented device, impaction bone grafting, allograft-prosthetic composite, or a segmental proximal femoral replacement may be required.

Vancouver type B2 and B3 periprosthetic fractures treated with revision total hip arthroplasty

PURPOSE

Periprosthetic fractures are the fourth most common cause for hip revision and a devastating complication. Our purpose is to report results and quality of life following revision THA for Vancouver B2 and B3 fractures.

METHODS

This was a retrospective review from January 2000 to November 2012 to identify all revision THA performed for Vancouver types B2 and B3 that had a minimum follow-up of two years. Routine post-operative and radiographic evaluation to assess patient survival, implant failure, complications and quality of life was involved. Statistical analysis was made with the Kaplan-Meier survival curve with 95 % confidence interval and the log rank (Mantel-Cox) test.

RESULTS

A total of 76 fractures were included, with an average follow-up 74.4 months. Mean age at the revision surgery was 75.7 years (range, 41-97 years; SD, 12.4). Sixty-six cases were classified as Vancouver B2 and treated with distal fixation stem. Ten cases were Vancouver B3 and a proximal femoral allograft technique was used. The overall five-year Kaplan-Meier survival rate for the patients was 77.9 % (95 % CI, 67.4-88.4), and the ten-year rate was 65.1 % (95 % CI, 51.4-78.8). Five-year Kaplan-Meier survival rate for the implants was 89.6 % (95 % CI, 82.2-97); we presented seven failures. The mean SF-12 mental was 55.1 (range, 31-68; SD, 8.1) and the physical was 37.4 (range, 16-55; SD, 9.4).

CONCLUSION

Mortality rate after periprosthetic fractures is high as compared to other hip surgeries; our Kaplan-Meier analysis showed that it tends to plateau after five years. In our series the failure rate was low and occurred early in the post-operative period.

The use of Gamma-irradiated proximal femoral allografts for bone stock reconstruction in complex revision hip arthroplasty

We have followed a consecutive series of 49 revision hip arthroplasties, performed for severe femoral bone loss using Gamma-irradiated anatomic-specific proximal femoral allografts longer than five centimetres. The patients were followed for a median 10.2 years, with a five year minimum follow-up. The median preoperative Harris Hip Score (HHS) improved from 42 points to 77 points postoperatively. In four hips the femoral component was further revised for non-union of the allograft and aseptic failure. In one hip the allograft and the femoral component were removed because of infection. In one hip the allograft and the femoral component were re-revised for host step-cut fracture. Junctional-union was observed in 44/49 hips. By defining success as an increase of HHS by 20 points or more, a stable implant and no need for any subsequent re-operations related to the allograft and /or the implant, a success rate of 76% was observed. Kaplan-Meier survivorship analysis predicted 79% rate of survival at 10 years and 75% rate of survival at 17 years, with the need for further revision of the allograft and/or implant as the end point. Three hips underwent re-attachment of the greater trochanter for trochanteric escape. Asymptomatic non-union of the greater trochanter was noticed in another three hips. Moderate allograft resorption was observed in four hips. Two fractures of the host step-cut occurred. There were four dislocations. Good long-term results with the use of large anatomic-specific femoral allografts justify their continued use in cases of revision hip arthroplasty complicated with severe femoral bone loss.

Proximal femoral reconstruction after aseptic loosening following proximal femoral replacement for Ewing sarcoma: a case report with one-year follow-up

We report the case of a 30-year-old patient initially treated for a proximal femoral Ewing's sarcoma when 12 years old. Index treatment comprised tumour resection and total hip arthroplasty. Two years later revision for aseptic loosening was performed. Subsequently, six further surgical revisons were performed for varying causes. At the age of 23 years the proximal femur was resected and a proximal femoral endoprosthesis implanted.Eighteen years after initial diagnosis the patient presented with recurrent aseptc loosening. Both the proximal femur and acetabulum were reconstructed. For acetabular reconstruction a structural allograft and a tantalum cup were utilised. Reconstruction of the femur utilsed extensive wire mesh and circlage wiring with impaction bone allograft into which a femoral stem was implanted.At one-year follow-up the patient was pain free, had no evidence of infection with satisfactory radiographs and no evidence of implant loosening. This is the first case reporting an extended proximal femoral reconstruction with a wire mesh in combination with impaction bone grafting in an aseptic loosened proximal femoral replacement following Ewing's Sarcoma.

Management bone loss of the proximal femur in revision hip arthroplasty: Update on reconstructive options

The number of revision total hip arthroplasties is expected to rise as the indications for arthroplasty will expand due to the aging population. The prevalence of extensive proximal femoral bone loss is expected to increase subsequently. The etiology of bone loss from the proximal femur after total hip arthroplasty is multifactorial. Stress shielding, massive osteolysis, extensive loosening and history of multiple surgeries consist the most common etiologies. Reconstruction of extensive bone loss of the proximal femur during a revision hip arthroplasty is a major challenge for even the most experienced orthopaedic surgeon. The amount of femoral bone loss and the bone quality of the remaining metaphyseal and diaphyseal bone dictate the selection of appropriate reconstructive option. These include the use of impaction allografting, distal press-fit fixation, allograft-prosthesis composites and tumor megaprostheses. This review article is a concise review of the current literature and provides an algorithmic approach for reconstruction of different types of proximal femoral bone defects.

Proximal femoral arthroplasty in patients undergoing revision hip arthroplasty

Bone loss represents one of the greatest challenges in revision joint surgery. A retrospective review was conducted of both radiographic and clinical outcomes of eleven patients who underwent revision arthroplasty using a long extensively porous coated cylindrical femoral component. All patients' femurs presented with severe proximal femoral bone loss (Paprosky class IIIB and IV). With a mean follow-up of 8 years (2 to 14) we report no femoral revisions and one acetabular revision to a constrained cup secondary to instability. All patients were clinically and radiographically stable. We did not observe any issue with proximal stress shielding or component loosening. The article reports that in patients with severe proximal femoral bone loss, extensively porous-coated non-modular stems are a viable option offering stable and predictable outcomes.

A Custom Trabecular Metal Implant in Revision Total Hip Replacement with a Paprosky Type-IV Femoral Defect: A Case Report

CASE

Treatment for severe femoral bone defects involving loss of the supporting isthmus is limited. Techniques are based on surgeon experience and patient-related factors. Revision arthroplasty can be challenging depending on bone loss and quality. Highly porous metals, such as trabecular metal, are ideal alternatives for complex reconstruction; however, little has been written about trabecular metal for reconstruction of the proximal part of the femur.

CONCLUSION

We report the five-year midterm results of a custom trabecular metal implant for a Paprosky type-IV femoral defect. This novel construct provides durable midterm survivorship and excellent function for Paprosky type-IV femoral bone loss.

The clinical and radiological evaluation of the use of an allograft-prosthesis composite in the treatment of proximal femoral giant cell tumours

Giant cell tumour is the most common aggressive benign tumour of the musculoskeletal system and has a high rate of local recurrence. When it occurs in proximity to the hip, reconstruction of the joint is a challenge. Options for reconstruction after wide resection include the use of a megaprosthesis or an allograft-prosthesis composite. We performed a clinical and radiological study to evaluate the functional results of a proximal femoral allograft-prosthesis composite in the treatment of proximal femoral giant cell tumour after wide resection. This was an observational study, between 2006 and 2012, of 18 patients with a mean age of 32 years (28 to 42) and a mean follow-up of 54 months (18 to 79). We achieved excellent outcomes using Harris Hip Score in 13 patients and a good outcome in five. All allografts united. There were no complications such as infection, failure, fracture or resorption of the graft, or recurrent tumour. Resection and reconstruction of giant cell tumours with proximal femoral allograft-prosthesis composite is a better option than using a prosthesis considering preservation of bone stock and excellent restoration of function. A good result requires demanding bone banking techniques, effective measures to prevent infection and stability at the allograft-host junction.

Treatment of failed allograft prosthesis composites used for hip arthroplasty in the setting of severe proximal femoral bone defects

This study assessed failures of allograft prosthesis composites (APC) and revisions with a new APC. Twenty-one patients with failed APC's after revision hip arthroplasty with severe proximal femoral bone loss underwent revision with a new APC. Causes of failure were aseptic loosening (18 patients), infection (3 patients). Of these 21 APC revisions, two patients failed (after 60, 156 months). The 5 and 10 year survival rates were 83.5% (95% CI, 79-100%, number at risk 12 and 6 accordingly). In addition, two patients had non-union at the host-allograft bone junction and were augmented with bone autograft and plate. These results suggest that failed APCs may be revised to a new APC with a predictable outcome.

Femoral bone loss in revision total hip arthroplasty: evaluation and management

Primary total hip arthroplasty (THA) is one of the most effective procedures for managing end-stage hip arthritis. The burden of revision THA procedures is expected to increase along with the rise in number of primary THAs. The major indications for revision THA include instability, aseptic loosening, infection, osteolysis, wear-related complications, periprosthetic fracture, component malposition, and catastrophic implant fracture. Each of these conditions may be associated with mild or advanced bone loss. Careful patient evaluation and bone loss classification guide preoperative planning and overall patient care. Historically, uncemented fixation has provided the best results, but cemented fixation is required in some cases.

Proximal femoral replacement and allograft prosthesis composite in the treatment of periprosthetic fractures with significant proximal bone loss

Femoral bone loss due to periprosthetic fracture, a challenging problem in total hip arthroplasty (THA), is increasingly encountered due to a rise in the number of revision THAs performed. Allograft prosthesis composite (APC) and proximal femoral replacement (PFR) are two available options for management of patients with difficult type-B3 Vancouver periprosthetic fractures. The treatment algorithm for patients with these fractures has been extensively studied and is influenced by the age and activity level of the patient. APC is often preferred in young and active patients in an attempt to preserve bone stock while older and less active patients are considered candidates for PFR. In spite of the high rate of overall complications with these two procedures, reported survivorship is acceptable. Treating patients with these complicated fractures is fraught with complications and, even with successful treatment, the outcomes are not as promising as those associated with primary hip replacement. In this paper, we aimed to review available published reports about PFR and APC for treatment of periprosthetic fractures around THAs.

Segmental proximal femoral bone loss and revision total hip replacement in patients with developmental dysplasia of the hip: the role of allograft prosthesis composite

The treatment of substantial proximal femoral bone loss in young patients with developmental dysplasia of the hip (DDH) is challenging. We retrospectively analysed the outcome of 28 patients (30 hips) with DDH who underwent revision total hip replacement (THR) in the presence of a deficient proximal femur, which was reconstructed with an allograft prosthetic composite. The mean follow-up was 15 years (8.5 to 25.5). The mean number of previous THRs was three (1 to 8). The mean age at primary THR and at the index reconstruction was 41 years (18 to 61) and 58.1 years (32 to 72), respectively. The indication for revision included mechanical loosening in 24 hips, infection in three and peri-prosthetic fracture in three. Six patients required removal and replacement of the allograft prosthetic composite, five for mechanical loosening and one for infection. The survivorship at ten, 15 and 20 years was 93% (95% confidence interval (CI) 91 to 100), 75.5% (95% CI 60 to 95) and 75.5% (95% CI 60 to 95), respectively, with 25, eight, and four patients at risk, respectively. Additionally, two junctional nonunions between the allograft and host femur required bone grafting and plating. An allograft prosthetic composite affords a good long-term outcome in the management of proximal femoral bone loss in revision THR in patients with DDH, while preserving distal host bone.

Proximal femoral allograft in revision hip surgery with severe femoral bone loss: a systematic review and meta-analysis

This study provides an objective appraisal of available evidence regarding the outcome of proximal femoral allograft for reconstruction of massive proximal femoral bone loss. The primary outcomes were rates of success, structural failure, and infection. A systematic literature review identified 16 studies with a minimum 2-year follow-up. Estimated pooled effect analysis performed with heterogeneity quantified using I(2) and τ(2). The total cohort included 498 patients with a mean follow-up of 8.1 years. The pooled success rate was 81%, pooled structural failure rate of 15%, and pooled infection rate of 8%. Significant heterogeneity was observed in structural failure rates (I(2) = 47.9, τ(2) = 0.29, P < .05). Proximal femoral allografts afford viable reconstruction for massive femoral bone loss when performed by experienced.

Dislocation and infection after revision total hip arthroplasty: comparison between the first and multiply revised total hip arthroplasty

Dislocation and infection are common complications of total hip arthroplasty (THA). This study evaluated the correlation between the number of revision THAs and the incidence of these complications. Data were obtained from 749 revision THAs. Average follow-up was 13.2 ± 5.9 years. Patients were grouped as first, second, third, and fourth or greater revision THA. Dislocation rates (5.68%, 7.69%, 8.33%, and 27.45%) and infection rates (1.35%, 1.92%, 2.5%, and 7.84%) in the first, second, third, and fourth or greater groups, respectively, correlated directly with the revision number and were highest (P < .001) in the fourth or greater group. Dislocation and infection are exponentially correlated with the number of revision THA. From the fourth revision onward, those risks are multiplied.

Proximal femoral allograft for major segmental femoral bone loss: a systematic literature review

As the indications for total hip arthroplasty increase, the prevalence of extensive proximal femoral bone loss will increase as a consequence of massive osteolysis, stress shielding and multiple revisions. Proximal femoral bone stock deficiency provides a major challenge for revision hip arthroplasty and is likely to account for a significant future caseload. Various surgical techniques have been advocated included impaction allografting, distal press-fit fixation and massive endoprosthetic reconstruction. This review article provides a systematic review of the current literature to assess the outcome of revision hip arthroplasty using allograft to reconstruction massive proximal femoral bone loss.

Structural allograft as an option for treating infected hip arthroplasty with massive bone loss

BACKGROUND

Revision of the infected hip arthroplasty with major bone loss is difficult. Attempts to restore bone stock with structural allograft are controversial.

QUESTIONS/PURPOSES

We assessed the (1) reinfection rate; (2) rerevision rate; (3) radiographic graft union, resorption, and implant migration; (4) Harris hip scores at 1 year and at last followup compared with before surgery; and (5) other major complications associated with the use of bulk structural allograft to treat massive bone loss in infected hip arthroplasty.

METHODS

We retrospectively reviewed 27 patients who underwent two-stage revision arthroplasty using structural allograft to treat massive bone defects in infected hip arthroplasty. There were 17 proximal femoral grafts, three acetabular major column grafts, two acetabular minor column grafts, and 10 cortical strut grafts used. Five patients had combinations of two allografts. The minimum followup was 1.1 years (mean, 8.2 years; range, 1.1-16.8 years).

RESULTS

One of 27 patients had reinfection. The Kaplan-Meier survivorship was 93% at 10 years with rerevision for aseptic loosening as the end point. Radiographically, three patients had nonunion at the graft-host junction. All patients except two had graft resorption, of which all were mild except two, which were severe. Three patients had implant migration. The mean modified Harris hip scores were 39.2 points (range, 25-60) preoperatively, 67.3 points (range, 40-91) at 1-year followup, and 70.3 points (range, 46-81) at last followup. Other major complications included one patient with dislocation and one patient with transient sciatic nerve injury.

CONCLUSIONS

Based on our data, we believe the use of structural allografts is a reasonable option for treating massive bone loss in infected hip arthroplasties.

LEVEL OF EVIDENCE

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

Revision total hip arthroplasty with a modular tapered stem

Femoral stem revision surgery with proximal bone loss may be treated with modular uncemented distal fixation stems. Early results of the ZMR tapered stems with relatively fewer cases were encouraging. In this prospective study, we evaluated the 2 to 10 years survivorship, associated complications and functional outcomes of 84 cases of femoral revision using the ZMR tapered stem. The indications for revision were aseptic loosening (50), periprosthetic fracture (12), infection (17), stem fracture (4) and instability (1). The mean follow-up was 46 months (range, 25-117). The Kaplan-Meier survival with femoral re-revision for any reason as an end-point was 92.7% (95% CI: 87.7%-97.7%). The mean Harris hip score improved from 37 (10-77) points before operation to 72 (41-96) points at last follow-up. The ZMR tapered stem has shown satisfactory results in 2 to 10 years followup in various femoral stem revision conditions.

Revision total hip arthroplasty with a porous-coated modular stem: 5 to 10 years follow-up

The ZMR porous stem is a modular cylindrical porous-coated femoral stem for revision THA. The objective of this study was to evaluate the clinical and radiographic outcomes of this stem at midterm followup. We prospectively reviewed 69 patients (72 femoral revisions) treated with the stem. The indication for revision was aseptic loosening in 61 (85%), periprosthetic fractures in five (7%), infection in three (4%), dislocation in two (3%), and fractured stem in one (1%). Minimum followup was 60 months (mean, 85 months; range, 60-114 months). The survival rate with revision for any reason as an end point was 93.8%. Mean preoperative Harris hip score was 39 points, and mean Harris hip score at last followup was 72 points. Four (5.5%) stems required rerevision, two (2.8%) for loosening, one (1.4%) for fracture at the modular junction, and one (1.4%) for infection. Subsidence occurred in eight (11%) patients, in the range of 5 to 25 mm. Two (2.89%) of the stems that subsided were symptomatic and progressive. The ZMR porous stem is a versatile system that offers a reliable fixation and an off-the-shelf solution for a multitude of femoral reconstruction challenges.

LEVEL OF EVIDENCE

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

Proximal femoral allograft-prosthesis composites in revision hip replacement: a 12-year follow-up study

We report the use of an allograft prosthetic composite for reconstruction of the skeletal defect in complex revision total hip replacement for severe proximal femoral bone loss. Between 1986 and 1999, 72 patients (20 men, 52 women) with a mean age of 59.9 years (38 to 78) underwent reconstruction using this technique. At a mean follow-up of 12 years (8 to 20) 57 patients were alive, 14 had died and one was lost to follow-up. Further revision was performed in 19 hips at a mean of 44.5 months (11 to 153) post-operatively. Causes of failure were aseptic loosening in four, allograft resorption in three, allograft nonunion in two, allograft fracture in four, fracture of the stem in one, and deep infection in five. The survivorship of the allograft-prosthesis composite at ten years was 69.0% (95% confidence interval 67.7 to 70.3) with 26 patients remaining at risk. Survivorship was statistically significantly affected by the severity of the pre-operative bone loss (Paprosky type IV; p = 0.019), the number of previous hip revisions exceeding two (p = 0.047), and the length of the allograft used (p = 0.005).

Proximal femur allograft-prosthesis with compression plates and a short stem

Proximal femur allograft-prosthesis composites (APCs) performed with compression plates and a short stem theoretically could minimize the resorption or nonunion that reportedly occurs with long stems bypassing the diaphyseal osteotomy. To confirm this theoretical consideration, we retrospectively reviewed 34 patients with 38 proximal femoral APCs using a short-cemented femoral stem and compression plates for diaphyseal osteotomy fixation. In 26 patients, the plate fixation extended over at least half the femoral stem and in 12, it did not. We reinserted the abductor mechanism with two techniques: in 10 cases the host trochanter was reattached to the APC, and in 28 the host tendons were sutured to the tendinous insertion of the allograft. The overall survival of the entire series was 72% at 5 years and 69% at 10 years. Eleven of the 38 (29%) APCs were removed: three for infection, one for local recurrence of tumor, and seven for fractures. Trendelenburg gait occurred in four of 21 patients with direct tendon-to-tendon suture of the abductor mechanism and in three of six patients with trochanteric osteotomy. The overall APC survival rate was greater in patients in whom the allograft was adequately protected with internal fixation than in patients in whom it was not.

LEVEL OF EVIDENCE

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

The use of allograft prosthesis composite for extensive proximal femoral bone deficiencies: a 2- to 9.8-year follow-up study

We report here results for 15 hips that we repaired using allograft prosthesis composite (APC) and monitored for a mean of 4.2 years. Two hips underwent repeat revisions with new APCs after a mean of 83.7 months. The average Harris Hip Score improved from 21.8 before revision surgery to 83.2 afterward, and 12 stems showed good stability. Of the 15 hips repaired with APC, 13 had good junctional union. One of the 2 remaining hips showed nonunion, which was repaired with an onlay graft 3.3 years later, and the other hip showed both infection and nonunion. There was 1 dislocation, and 2 hips had complications related to the greater trochanter. Our findings demonstrate that the use of APC produces satisfactory results.