Massive Bone Defects Research Articles

Bridging compound internal fixation system for treatment of femoral fractures with postoperative infection

Objective To investigate the curative effect of the non-contact bridging compound internal fixation system in the treatment of femoral fractures with postoperative infection. Methods From March 2011 to December 2014, 17 patients with femoral fracture were complicated with postoperative infection. They were 13 males and 4 females, from 16 to 61 years of age (average, 43.2 years). Six cases were at the left side and 11 at the right side. By AO/OTA classification, there were 2 cases of type 32-A2 and 2 cases of type 32-A3; 3 cases of type 32-B2 and 4 cases of type 32-B3; 2 cases of type 32-C1, 3 cases of type 32-C2 and one of type 32-C3. Unilateral external fixators had been used in 11 cases and compound external fixators in 6 cases. The time between primary fixation and bridging internal fixation ranged from 32 to 71 days (average, 41.5 days). After removal of original fixation and necrotic tissue at fracture ends, non-contact bridging compound internal fixation system was applied to fix the fracture. Results All the 17 patients received postoperative follow-up for 12 to 24 months (average, 17.9 months). All the surgical incisions healed by one intention. All the postoperative laboratory indicators were normal, including blood routine examination, blood sedimentation and C-reactive protein. Two patients had to undergo secondary iliac cancellous bone graft due to massive bone defects. X-ray examination one year later revealed bony union in all the 17 cases of femoral fracture. No recurrence of infection was observed before removal of internal fixation. At the final follow-up, the knee joint function by the Kolmert evaluation was excellent in 10 cases, good in 6 cases, and fair in one. Conclusion Non-contact bridging compound internal fixation system can be used in treatment of femoral fractures with postoperative infection to prevent recurrence of infection. Key words: Femoral fractures; Infection; Fracture fixation, internal; Wounds and injuries

“Reverse” hip spacer for massive distal femur defects in peri-prosthetic knee infections

BackgroundBone loss in the distal femur is a common problem in knee revision surgeries. The problem is exacerbated in the context of an active infection. In extreme cases this bone loss could compromise the feasibility of a two-stage exchange protocol using dynamic spacers due to the inherent instability of this type of spacers. Use of a hip prefabricated spacer in a “reverse” way forming a ball-and-socket joint is a therapeutic option in cases of massive bone defect and infection. Material and methodsA retrospective review was performed of our institutional database to identify all cases of massive distal femoral defect in which this technique was used from January 2010 to December 2013. A record was made of the epidemiological data, characteristics of the infection (clinical and microbiological), and adverse event during the spacer stage. The main end-point was the infection eradication rate (minimum: 18 months of follow-up). The complications associated with the technique were also assessed. Finally, each patient completed a visual analogue pain scale, and a satisfaction questionnaire (SAPS). ResultsThis technique was successfully used in six cases so far, controlling the infection in all cases. Mean femoral defect was 117cm (range: 32–191cm). Mean time with spacer was 7.6 months, with no major complications. All but one patient reached second stage reconstruction with a mega-prosthesis, and mean time since second stage was 34.7 months. All patients stated high levels of satisfaction with the technique employed, as well as and low pain scores (mean visual analogue pain scale: 1; range: 0–4). ConclusionA reproducible and safe technique is described. Patients report a high level of satisfaction with the procedure, and there were no cases of recurrence of the infection after a minimum follow-up of 18 months.

Establishment of a Segmental Femoral Critical-size Defect Model in Mice Stabilized by Plate Osteosynthesis

The use of tissue-engineered bone constructs is an appealing strategy to overcome drawbacks of autografts for the treatment of massive bone defects. As a model organism, the mouse has already been widely used in bone-related research. Large diaphyseal bone defect models in mice, however, are sparse and often use bone fixation which fills the bone marrow cavity and does not provide optimal mechanical stability. The objectives of the current study were to develop a critical-size, segmental, femoral defect in nude mice. A 3.5-mm mid-diaphyseal femoral ostectomy (approximately 25% of the femur length) was performed using a dedicated jig, and was stabilized with an anterior located locking plate and 4 locking screws. The bone defect was subsequently either left empty or filled with a bone substitute (syngenic bone graft or coralline scaffold). Bone healing was monitored noninvasively using radiography and in vivo micro-computed-tomography and was subsequently assessed by ex vivo micro-computed-tomography and undecalcified histology after animal sacrifice, 10 weeks postoperatively. The recovery of all mice was excellent, a full-weight-bearing was observed within one day following the surgical procedure. Furthermore, stable bone fixation and consistent fixation of the implanted materials were achieved in all animals tested throughout the study. When the bone defects were left empty, non-union was consistently obtained. In contrast, when the bone defects were filled with syngenic bone grafts, bone union was always observed. When the bone defects were filled with coralline scaffolds, newly-formed bone was observed in the interface between bone resection edges and the scaffold, as well as within a short distance within the scaffold. The present model describes a reproducible critical-size femoral defect stabilized by plate osteosynthesis with low morbidity in mice. The new load-bearing segmental bone defect model could be useful for studying the underlying mechanisms in bone regeneration pertinent to orthopaedic applications.

Establishment of a Segmental Femoral Critical-size Defect Model in Mice Stabilized by Plate Osteosynthesis.

The use of tissue-engineered bone constructs is an appealing strategy to overcome drawbacks of autografts for the treatment of massive bone defects. As a model organism, the mouse has already been widely used in bone-related research. Large diaphyseal bone defect models in mice, however, are sparse and often use bone fixation which fills the bone marrow cavity and does not provide optimal mechanical stability. The objectives of the current study were to develop a critical-size, segmental, femoral defect in nude mice. A 3.5-mm mid-diaphyseal femoral ostectomy (approximately 25% of the femur length) was performed using a dedicated jig, and was stabilized with an anterior located locking plate and 4 locking screws. The bone defect was subsequently either left empty or filled with a bone substitute (syngenic bone graft or coralline scaffold). Bone healing was monitored noninvasively using radiography and in vivo micro-computed-tomography and was subsequently assessed by ex vivo micro-computed-tomography and undecalcified histology after animal sacrifice, 10 weeks postoperatively. The recovery of all mice was excellent, a full-weight-bearing was observed within one day following the surgical procedure. Furthermore, stable bone fixation and consistent fixation of the implanted materials were achieved in all animals tested throughout the study. When the bone defects were left empty, non-union was consistently obtained. In contrast, when the bone defects were filled with syngenic bone grafts, bone union was always observed. When the bone defects were filled with coralline scaffolds, newly-formed bone was observed in the interface between bone resection edges and the scaffold, as well as within a short distance within the scaffold. The present model describes a reproducible critical-size femoral defect stabilized by plate osteosynthesis with low morbidity in mice. The new load-bearing segmental bone defect model could be useful for studying the underlying mechanisms in bone regeneration pertinent to orthopaedic applications.

Endemic impact of human T cell leukemia virus type 1 screening in bone allografts.

Allograft bone is a widely used as a convenient tool for reconstructing massive bone defects in orthopedic surgery. However, allografts are associated with the risk of viral disease transmission. One of the viruses transmitted in this manner is human T-lymphotropic virus type 1 (HTLV-1), which is found worldwide but is unevenly distributed. The southwestern parts of Japan are a highly endemic for HTLV-1. We investigated the HTLV-1 seroprevalence in candidate allograft donors at the regional bone bank in Kagoshima, Japan during its first 5 years of service. Between 2008 and 2012, we collected 282 femoral heads at the Kagoshima regional bone bank from living donors with osteoarthritis of the hip joint. Among the 282 candidate donors, 32 donors (11.3 %) were seropositive for anti-HTLV-1 antibody; notably, this prevalence is higher than that reported for blood donors in this area. Additionally, to determine if HTLV-1 genes are detectable after processing, we examined the bone marrow of the femoral heads from seropositive donors by conducting PCR assays. Our results confirm the existence of viral genes following the heat treatment processing of the femoral heads. Therefore, it is important to inactivate a virus completely by heat-treatment. Together, our findings highlight the importance of HTLV-1 screening at bone banks, particularly in HTLV-1-endemic areas such as southwest Japan.

Bone Remodeling in Acetabular Reconstruction Using a Kerboull-Type Reinforcement Device and Structural Bone-Grafting in Total Hip Arthroplasty

BackgroundThe purpose of this study was to identify the long-term durability of the Kerboull-type reinforcement device (KT plate) in acetabular reconstruction for massive bone defects, assessing the remodeling of structural bone grafts. MethodsThis study retrospectively evaluated 106 hips that underwent acetabular reconstruction using a KT plate between November 2000 and December 2010. Thirty-eight primary total hip arthoplasties (THAs) and 68 revised THAs were performed, and the mean duration of clinical follow-up was 8 years (5-14 years). Regarding reconstructing the acetabular bone defects, autografts were used in 37 hips, allografts in 68 hips, and A-W glass ceramics in 2 hips. ResultsOne hip exhibited radiological migration and no revision for aseptic loosening. The mean Merle d'Aubigné Clinical Score improved from 7.5 points (4-12 points) preoperatively to 10.9 points (9-18 points) at the last follow-up. The Kaplan–Meier survival rate for radiological migration of primary and revised THAs at 10 years was 100% and 97% (95% confidence interval: 96%-100%), respectively. Bone remodeling was evaluated using the radiological demarcation at the bone-to-bone interface, and an improvement of 100% in primary THAs and 94% in revised THAs was observed. ConclusionFor massive bone defects, acetabular reconstruction using the KT plate with a structural bone grafting can yield successful results.

Inserting the Ulnar Prosthesis into Radius as a Novel Salvage Surgery for Revision Total Elbow Arthroplasty with Massive Bone Defect.

Background:Infection and aseptic loosening are common complications of total elbow arthroplasty (TEA) and often require revision surgery. However, bone defects, along with other complications, bring an extra difficulty to the second surgery, especially for patients with a massive bone defect in the proximal ulna. Several methods including allograft or autograft have been introduced into practice, but none sufficiently solves these problems.Methods:We conducted a new surgical method for patients with a massive ulnar bone defect needing revision TEA. During revision arthroplasty, the ulnar prosthesis was inserted into the radius as a salvage procedure. Four consecutive patients received revision arthroplasty with this method between 2013 and 2016. Patients’ data were collected to evaluate the clinical outcome.Results:All patients had a Grade III ulnar bone defect. At the last follow-up session, all patients reported a painless, functional elbow joint. Three patients suffered from a periprosthetic infection that was completely cured using the two-stage method. No major complications, including infection, aseptic loosening, or wound problems were found. One patient had a transient ulnar neuritis, and another had a transient radial neuritis. Both patients had full recovery at the last follow-up session.Conclusions:Inserting an ulnar prosthesis into the radius is a novel procedure for patients with a massive bone defect due to infection or aseptic loosening. It is a safe, quick, and effective treatment with a promising short-term outcome. This method should be provided as a salvage procedure for patients with a nonreconstructable ulnar bone defect.

Espaciador de cadera «invertido» para defectos masivos de fémur distal en infecciones periprotésicas de rodilla

BackgroundBone loss in the distal femur is a common problem in knee revision surgeries. The problem is exacerbated in the context of an active infection. In extreme cases this bone loss could compromise the feasibility of a two-stage exchange protocol using dynamic spacers due to the inherent instability of this type of spacers. Use of a hip prefabricated spacer in a “reverse” way forming a ball-and- socket joint is a therapeutic option in cases of massive bone defect and infection. Material and methodsA retrospective review was performed of our institutional database to identify all cases of massive distal femoral defect in which this technique was used from January 2010 to December 2013. A record was made of the epidemiological data, characteristics of the infection (clinical and microbiological), and adverse event during the spacer stage. The main end-point was the infection eradication rate (minimum: 18 months of follow-up). The complications associated with the technique were also assessed. Finally, each patient completed a visual analogue pain scale, and a satisfaction questionnaire (SAPS). ResultsThis technique was successfully used in six cases so far, controlling the infection in all cases. Mean femoral defect was 117cm (range: 32-191cm). Mean time with spacer was 7.6 months, with no major complications. All but one patient reached second stage reconstruction with a mega-prosthesis, and mean time since second stage was 34.7 months. All patients stated high levels of satisfaction with the technique employed, as well as and low pain scores (mean visual analogue pain scale: 1; range: 0-4). ConclusionA reproducible and safe technique is described. Patients report a high level of satisfaction with the procedure, and there were no cases of recurrence of the infection after a minimum follow-up of 18 months.

Allograft-prosthetic composite versus megaprosthesis in the proximal tibia—What works best?

Modular megaprosthesis (MP) and allograft-prosthetic composite (APC) are the most commonly used reconstructions for large bone defects of the proximal tibia. The primary objective of this study was to compare the two different techniques in terms of failures and functional results.A total of 42 consecutive patients with a mean age of 39.6 years (range 15–81 years) who underwent a reconstruction of the proximal tibia between 2001 and 2012 were included. Twenty-three patients were given an MP, and 19 patients received an APC. There were nine reconstruction failures after an average follow-up of 62 months: five in the MP group and four in the APC group (p=0.957). The 10-year implant survival rate was 78.8% for the MP and 93.7% for the APC (p=0.224). There were no relevant differences between the two groups in functional results. Both MP and APC are valid and satisfactory reconstructive options for massive bone defects in the proximal tibia. In high-demanding patients with no further risk factors, an APC should be considered to provide the best possible functional result for the extensor mechanism.

Reconstruction of acetabulum in revision total hip arthroplasty for pelvic discontinuity: report of a difficult case requiring four revision arthroplasty.

BackgroundMassive bone defects of the acetabulum with pelvic discontinuity are one of the major problems in revision total hip arthroplasty. Several techniques have been described for repair of acetabular defect; however, reconstruction of acetabulum with massive bone defect is still a major problem. We describe a patient who required four revision total hip arthroplasty during a 24-year period.FindingsThe acetabulum with pelvic discontinuity was successfully reconstructed by stabilization of the posterior column with a plate commonly used for fracture treatment, and stabilization of the anterior column by reinforcement device commonly used for acetabular reconstruction. Fixation of both acetabular columns provided significant improvement of component stability.ConclusionsIn the case of pelvic discontinuity with massive acetabular bone defect, reconstruction by stabilizing both acetabular columns using reconstruction plate and KT plate is one of the better surgical options.

Is unicondylar osteoarticular allograft still a viable option for reconstructions around the knee?

BackgroundUnicondylar osteoarticular allografts (UOAs) represent a possible technique for reconstructing massive bone defects around the knee when only one condyle is affected. The aim of this retrospective study is to evaluate the outcome of UOAs and describe the possible salvage procedures in case of graft failure. MethodsTwenty-five deep-frozen UOAs were implanted at Rizzoli Orthopedic Institute (Bologna, Italy). Twenty-two followed bone tumor resection, two cases were post-traumatic defects and one case followed UOA failure.Mean age at surgery was 33years (range: 15 to 63). Eighteen UOAs were in distal femur, seven in proximal tibia. ResultsThree patients died (only one because of the tumor). One UOA was removed for chondrosarcoma relapse and one for allograft fracture. Mean overall survival with UOA failure as a primary endpoint was 129months (range 12 to 302), with differences in the femur (85%) and in the tibia (40%) at 150months. Six UOAs had to be converted into knee prostheses due to osteoarthritis after a mean follow-up of 146months. No complications were recorded in UOAs converted into knee prostheses after a mean three year follow-up. Fourteen patients with UOAs still in place at the last follow-up (mean 123months) were radiologically and functionally evaluated: no correlation was found between function and the degree of osteoarthritis. ConclusionsIn selected cases, UOAs offer good clinical results and postpone the need for knee prosthesis. Despite short-term encouraging results, longer-term follow-up is needed in order to evaluate the outcome of knee prosthesis after UOA.

Total knee arthroplasty in patients with Charcot joints.

Although total knee arthroplasty (TKA) entails diverse operative techniques and achieves varying results in patients with different knee pathologies, few studies have discussed TKA for Charcot joints. This study aimed to investigate the efficacy of TKA in patients with Charcot knees. From 2009 to 2013, seven patients with eight Charcot knees were admitted to our institution. They were confirmed by pre-operative examination and subsequently underwent TKAs. The pre-operative clinical and imaging characteristics of their knees indicated that all were in the Charcot stages of reconstruction or coalescence. Rotating hinge prostheses were selected for three knees with severe bone deficiency and soft tissue imbalance, whereas long stem condylar-constrained prostheses were implanted in the remaining five cases. Autogenous bone grafts were used in three patients to repair residual defects after osteotomy. Clinical data, including Hospital for Special Surgery (HSS) knee scores, range of motion (ROM), complications, and radiographic data, were used to assess surgical efficacy. The mean HSS score increased from 45.8±14.2 (24-60) points pre-operatively to 84.6±4.8 (75-90) points at final follow-up (P<0.01). ROM was 65°±25° (30°-100°) pre-operatively and 92°±11° (75°-110°) after arthroplasty (P<0.05), indicating satisfactory outcomes. Radiographic findings, including assessment for prosthetic loosening and alignment changes, suggested favourable outcomes. TKA using constrained condylar or rotating hinge prostheses and autografts for massive bone defects is effective for Charcot knees in the reconstruction or coalescence stage. IV.

Clinical evaluation following the use of mineralized collagen graft for bone defects in revision total hip arthroplasty

Revision total hip arthroplasty (THA) with massive bone loss has been a real challenge for orthopaedic surgeons. Here we describe an approach using mineralized collagen (MC) graft to reconstruct acetabulum and femur with massive bone defects. We identified 89 patients suffering acetabular or femoral bone defects after primary THA, who required revision THA for this study. During the surgery, MC was applied to reconstruct both the acetabular and femoral defects. Harris hip score was used to evaluate hip function while radiographs were taken to estimate bone formation in the defect regions. The average follow-up period was 33.6 ± 2.4 months. None of the components needed re-revised. Mean Harris hip scores were 42.5 ± 3.5 before operation, 75.2 ± 4.0 at 10th month and 95.0 ± 3.6 at the final follow-up. There were no instances of deep infection, severe venous thrombosis or nerve palsy. The present study demonstrated that MC graft can serve as a promising option for revision THA with massive bone deficiency. Meanwhile, extended follow-up is needed to further prove its long-term performance.

An evaluation of the effect of bone morphogenetic protein-2 in a hydroxyapatite carrier on the rate of cortical restoration of large bone defects using the dog ulna model

To evaluate the rate of establishment of cortical continuity and union of large bone defects with the use of recombinant bone morphogenetic protein (rh-BMP- 2)/hydroxyapatite implants. Six adult male dogs were used to evaluate the effect of bone morphogenetic proteins (BMP) in filling large cortical defects. A 1.5cm cortical ulnar defect was created in two groups of dogs. First group had 1.5cm BMP implant in a carrier of hydroxyapatite in the cortical defect; the control (group 2) defect was left intact. Evaluation was through serial radiographic determination of mean fracture gaps. There was progressive filling of osseous defects in group 1, which was total at the 16th week post-surgical (PS); group 2 dogs had radiographic non-union at the 16th PS week. It was concluded that BMP implanted with a hydroxyapatite carrier significantly enhanced the rate of cortical restoration of massive bone defects in dogs. Keywords : Bone healing, Bone morphogenetic protein-2, Cortical growth, Dogs, Segmental bone defects, Ulna

Proximal humeral osteoarticular allografts: technique, pearls and pitfalls, outcomes.

Allograft transplantation is a biologic reconstruction option for massive bone defects after resection of bone sarcomas. This type of reconstruction not only restores bone stock but it also allows us to reconstruct the joint anatomically. These factors are a major concern, especially in a young and active population.We are describing indications, surgical techniques, pearls and pitfalls, and outcomes of proximal humeral osteoarticular allografts, done at present time in our institution.We found that allograft fractures and articular complications, as epiphyseal resorption and subchondral fracture, are the main complications observed in proximal humerus osteoarticular allograft reconstructions. Nevertheless, only fractures need a reconstruction revision. Joint complications may adversely affect the limb function, but for this reason, an allograft revision is rarely performed.

Ipsilateral fibula transport for the treatment of massive tibial bone defects

ObjectiveThe objective of the study was to evaluate the effectiveness of the treatment of massive tibial bone defects by ipsilateral fibula transport. Materials and methodsNine patients with massive tibial bone defects were retrospectively reviewed. There were 7 males and 2 females with an average age of 32.22 years. The mean length of bone defect was 15.67cm (range 13–25cm). ResultsAll patients were followed up and the mean time of follow up was 40.11 months (range 26–60 months). All the patients achieved bone union and the average external fixation time was 11.67 months (range 9–14 months). The mean degrees of knee extension were 2.2°(range 0–5°) and the mean degrees of knee flexion were 131.7° (range 120–140°). The mean degrees of ankle dorsiflexion were 8.9° (range 0–15°) and the mean degrees of ankle plantar flexion were 30° (range 20–40°). ConclusionOur study suggested that ipsilateral fibula transport in the treatment of massive tibial bone defects acquired satisfying functional results. It may be a better choice for the patients without suitable proximal or distal tibia remnant to transport.

The use of customized cages in revision total hip arthroplasty for Paprosky type III acetabular bone defects.

Revision total hip arthroplasty (THA) is challenging if severe periacetabular bone loss is present. Here we describe a method that uses a customised cage to reconstruct an acetabulum with a massive bone defect. Designed with the aid of the rapid prototyping technique, a customised cage with a hook, crest and flange or braids was made, and then utilized to reconstruct severe compromised acetabulum in revision THA since 2001. Twenty-two patients (23 hips) were included in this study. The mean patient age at the time of surgery was 60.9 years (range, 38-80 years). Three hips had massive acetabular bone defects of Paprosky type IIIA and 20 of type IIIB. The Harris hip score was used to evaluate hip function. Radiographs were taken to evaluate loosening of the cage and resorption of allograft bone. The average follow up was 81.6 ± 24.9 months. The mean Harris hip score improved from 39.6 pre-operatively to 80.9 at the final follow-up. There were no instances of deep infection, severe venous thrombosis, and nerve palsy. One patient who had an intra-operative rupture of the superior acetabular artery was successfully treated using the haemostatic suturing technique. Two patients experienced dislocation at post-operative days four and six, respectively, and both were treated with closed reduction and skin traction for three weeks. The present study demonstrates that a customised cage may be a promising option for THA revision of severely compromised acetabula. Extended follow-up is necessary to evaluate the long-term performance of this approach.

Long-term outcome of free fibula osteocutaneous flap and massive allograft in the reconstruction of long bone defect

Reconstruction of massive bone defects in bone tumors with allografts has been shown to have significant complications including infection, delayed or nonunion of allograft, and allograft fracture. Resection compounded with soft tissue defects requires skin coverage. A composite osteocutaneous free fibula offers an optimal solution where the allografts can be augmented mechanically and achieve biological incorporation. Following resection, the cutaneous component of the free osteocutaneous fibula flaps covers the massive soft tissue defect. In this retrospective study, the long-term outcome of 12 patients, who underwent single-stage limb reconstruction with massive allograft and free fibula osteocutaneous flaps instead of free fibula osteal flaps only, was evaluated. This study included 12 consecutive patients who had primary bone tumors and had follow-up for a minimum of 24 months. The mean age at the time of surgery was 19.8 years. A total of eight patients had primary malignant bone tumors (five osteosarcomas, two chondrosarcomas and one synovial sarcoma), and four patients had benign bone tumors (two giant-cell tumors, one aneurysmal bone cyst, and one neurofibromatosis). The mean follow-up for the 12 patients was 63 months (range 24-124 months). Out of the 10 patients, nine underwent lower-limb reconstruction and ambulated with partial weight bearing and full weight bearing at an average of 4.2 months and 8.2 months, respectively. In conclusion, augmentation of a massive allograft with free fibula osteocutaneous flap is an excellent alternative for reducing the long-term complication of massive allograft and concurrently addresses the soft tissue coverage.

The use of porous metal cones in revision total knee arthroplasty

Massive bone defects represent a major problem in revision total knee arthroplasty. Traditionally, structural allograft has been used for this purpose; however, this is technically demanding and is associated with a failure rate. Metaphyseal tantalum cones have been a major advancement. They have made surgery easier and have yielded better results when compared to reconstruction with allograft. Adding the ability to comfortably use these implants to one’s armamentarium should be a priority for surgeons who regularly revise total knee replacements. These implants have completely replaced the use of structural allografts in the authors’ practice.

Total Femur Replacement After Tumor Resection: Limb Salvage Usually Achieved But Complications and Failures are Common.

Primary bone or soft tissue tumors of the femur sometimes present with severe and extensive bone destruction, leaving few limb-salvage options other than total femur replacement. However, there are few data available regarding total femur replacement and, in particular, regarding implant failures. We asked: (1) What are the revision-free and overall implant survival rates of conventional total femur replacements in patients treated for sarcoma of the femur or soft tissues? (2) What are the revision-free and overall implant survival rates of expandable total femur replacements in skeletally immature patients? (3) Using the comprehensive International Society of Limb Salvage failure-mode classification, what types of complications occur with conventional and expandable total femur replacements? Our retrospective, single-center cohort study was based on data prospectively collected for 50 patients who received a total femur replacement after tumor resection for indications other than carcinoma or metastatic disease. Of the 50 patients, six (12%) were lost to followup before 6months. Ten of the remaining 44 patients received expandable implants. The mean followup was 57months (range, 1-280months) and 172months (range, 43-289months) for patients who underwent conventional and expandable total femur replacements, respectively. For implant survival, competing risk analyses were used. At 5years, revision-free implant survival of conventional total femur replacements was 48% (95% CI, 0.37-0.73), and overall implant survival was 97% (95% CI, 0.004-0.20). Five-year revision-free implant survival of expandable total femur replacements was 30% (95% CI, 0.47-1.00) and overall implant survival was 100%. With conventional total femur replacements soft tissue failures occurred in 13 of 34 patients, structural failures in three, infection in six, and local tumor progression in one. No patient had aseptic loosening with conventional total femur replacements, but hip disarticulation occurred in two patients owing to extensive wound-healing problems and infection. With expandable total femur replacements soft tissue failure, aseptic loosening, and infection occurred in one patient each of 10, and structural failures in three of 10 (two periprosthetic fractures, one loosening of an enhanced tendon anchor). No hip disarticulations were performed. Additionally expandable total femur replacement-related failures included hip instability in eight of 10 patients, contractures attributable to massive scar tissue in six, and defect of the implant's expansion mechanism in four patients. Although the indications for total femoral resection are rare, we think that total femur replacement is a reasonable treatment option for reconstruction of massive femoral bone defects after tumor resection in adults and skeletally immature patients, and results in limb salvage in most patients. Level IV, therapeutic study.