Severe Femoral Bone Loss Research Articles

Clinical outcomes and survival rates of a uncemented modular revision stem system in hip arthroplasty: a 10-year single-institution study on a frail population

IntroductionThe increasing prevalence of primary hip arthroplasty has led to a parallel rise in revision cases. Femoral revision often entails compromised bone integrity, requiring consideration of various solutions for optimal reconstructive options. Despite technological advancements, there is limited evidence on the clinical outcomes of the latest modular revision stems. This study aimed to evaluate the clinical outcomes and survival rates of next generation uncemented modular revision stem in patients undergoing hip revision surgery.Materials and methodsThis retrospective single-center study assessed the survival and failure causes of a specific uncemented modular stem in 48 patients undergoing hip revision surgery between 2012 and 2022. Data included preoperative parameters, surgical details, and postoperative outcomes measured through clinical and radiographic assessments. Forty-eight patients (25 males, 23 females; mean age 72 years) were included, with a mean Charlson Comorbidity Index of 5. Preoperative diagnoses varied, with periprosthetic joint infection (PJI) being the most common (45.8%), followed by periprosthetic fractures (27.1%). Partial revisions occurred in 60.4%, total revisions in 39.6%. According to Paprosky classification of femoral bone loss, type II and III were the most represented, respectively 35.4% and 50%.ResultsAt a mean follow-up of 4.6 years, stem survival was 92.5%. Complications (20%) included dislocation, PJI, fracture, and loosening; the overall reoperation rate was 12.5%. The SF-12 physical score was 43.6, while the mental score was 51.1. The HOOS score was 71.8, and the HHS score was 71.4. Radiographic analysis identified nonprogressive osteolysis in 15.1% of patients.ConclusionsThis study on this uncemented modular revision stem demonstrated favorable outcomes in an elder fragile population with moderate to severe femoral bone loss. The implant’s modularity provides versatility in addressing various defects, without any implant breakage observed during the study period. Literature comparison highlighted similar outcomes despite sample size differences. The promising results warrant continued investigation into the long-term survivorship of this modular stem system.

Prediction of Distal Femoral and Posterior Articular Surfaces in Total Knee Arthroplasty With Severe Bone Defects Using Computed Tomography-Based Templating Software.

Introduction Optimal repair of the joint line (JL) in total knee arthroplasty (TKA) is critical for knee joint motion reconstruction and ligament balance. Identification of JL may be difficult, particularly in revision or primary cases of severe femoral condylar bone loss. We aimed to define the relationship between the epicondyles and the articular surface (AS) of the femur using computed tomography-based three-dimensional digital templating software. Methods The study included 127 knees with osteoarthritis of the knee below grade 2 on the Kellgren-Lawrence index. A perpendicular line was drawn from the medial and lateral femoral epicondylar processes to the most distal point of the AS, and the distance was measured in the axial and coronal planes. Femoral width was measured as the distance between the medial and lateral epicondyles. All distances described above were converted to a ratio by division with femoral width. Results On the axial plane, the distance from epicondyles to the posterior ASs was 29.4 ± 2.2 mm medially and 21.3 ± 2.1 mm laterally. The width of the distal femur was 75.2 ± 4.2 mm. On the coronal plane, the distances from epicondyles to the distal ASs were 25.2 ± 2.9 mm on the medial side and 21.3 ± 2.5 mm on the lateral side. The ratio of the distance from epicondyles to the distal and posterior ASs divided by the width of the femur was 0.39 ± 0.02, 0.28 ± 0.03, 0.34 ± 0.03, and 0.28 ± 0.03. Conclusions The distance from the epicondyles to the distal and posterior JLs correlates with the distal femur width. These findings may be useful in determining an appropriate JL.

ACHIEVING DISTAL FIXATION AND EARLY MOBILIZATION IN PATIENTS WITH SEVERE FEMORAL BONE LOSS USING AN INTERNAL PROXIMAL FEMORAL REPLACEMENT PROSTHESIS

The management of femoral bone loss is challenging during revision hip arthroplasty. In patients with Paprosky grade IIIB and IV defects, obtaining fixation and rotational stability using traditional surgical constructs is difficult. The use of a custom-made internal proximal femoral replacement prostheses has been proposed as a solution in patients, with severe femoral bone stock loss. However, there is a paucity in the literature on their use and long-term outcomes. We report on the clinical and radiological results of our cohort.We retrospectively reviewed all patients who underwent internal proximal femoral replacement for revision hip arthroplasty between April 1996 and April 2019. All patients had at least 2 years of follow-up time.160 patients underwent limb salvage at our institution using internal proximal femoral replacement. The mean follow-up was 79.7 months (S.D 41.3). Indications for revision included periprosthetic fractures, aseptic loosening, and deep infection. The mean Oxford hip score increased from 13.8 (0–22) to 31.5 (18–43) (paired t-test, p < 0.001). Kaplan-Meier prosthesis survival analysis with revision as the endpoint was 87% at 5 years. None required revision of the femoral stem. There were four dislocations (5%) and there was failure to eradicate the deep infection in four.This technique allows instant distal fixation, allowing for early mobilisation. Long-term clinical and radiological outcomes are encouraging and the complication rates are acceptable for this patient group.

Implant Survival of an Uncemented Modular Femoral Implant in Patients With Severe Femoral Bone Loss and 2‐Stage Hip Revision

Background and Purpose: Revision total hip arthroplasty (rTHA) is a challenging procedure especially in the presence of severe bone loss where implant fixation is compromised. The aim of this study was to evaluate implant survival, clinical outcome, and midterm results in a group of complex patients after femoral revision using an uncemented modular implant design.Patients and Methods: We performed a retrospective study including 100 patients (101 hips) treated with revision THA using an uncemented modular implant design. We identified 51 hips as Paprosky types I‐II and 50 hips as Paprosky III‐IV bone defects. We reviewed operative reports and radiographs. Patients underwent a clinical examination to assess the Harris Hip Score (HHS) and completed patient‐reported outcome measures (PROM), including the Oxford Hip Score (OHS) and the EQ‐5D Visual Analog Scale (VAS). Minimum follow‐up was 2 years (average, 5.8 years; range, 2.0–9.4 years).Results: Among the cases, 46 hips were revised for infection in a 2‐stage procedure and 44 hips for aseptic loosening. 11 hips had periprosthetic fractures of Vancouver type B2 or B3. A total of 5 hips required revision with removal of the femoral implant and 11 patients experienced complications resulting in fracture (n = 1), dislocation (n = 10), and soft tissue revision (n = 1). The 5‐year implant survival estimated by Kaplan–Meier survival analysis was 95% (95%‐CI: 91%–99%). All hips had radiographic evidence of osseointegration and no one with subsidence greater than 5 mm. Additionally, 80% showed radiographic evidence of restoration of proximal femoral bone. Mean HHS was 78.Conclusion: In complex cases of revision THA, using a modular revision femoral system yielded promising results. The 5‐year implant survival estimated by Kaplan–Meier survival analysis was 95% (95%‐CI: 91%–99%), with all hips demonstrating radiographic evidence of osseointegration and no one with subsidence greater than 5 mm. Notably 80% showed radiographic evidence of restoration of proximal femoral bone.

Excellent Survival Rate of Cemented Modular Stems in One-Stage Revision for Periprosthetic Hip Infections With Massive Femoral Bone Loss: A Retrospective Single-Center Analysis of 150 Cases

BackgroundWith the increasing incidence of total hip arthroplasty (THA), there is also an expected concurrent increase in revision THA (rTHA), which is known to have a high complication and re-revision rate. In the setting of infection, radical debridement is essential and options for femoral bone loss are limited. One viable solution is cemented modular stems, but limited evidence exists on their use in septic revision. This study aimed to analyze survival and complication related to the use of cemented modular stems in one-stage septic rTHA with severe femoral bone loss. MethodsThe institutional database of patients who underwent rTHA for septic one-stage revision with cemented modular stems was reviewed. Exclusion criteria were patients aged less than 18 years and nonseptic or 2 stage revisions. Outcomes measured were complication, re-infection, re-operation, and survivorship of the implant. A total of 150 patients were included. The mean age was 68 years (range, 30 to 91), and the mean follow-up was 105 months (range, 1 to 150). ResultsTreatment was considered successful in 81.3% of cases. Patients who underwent multiple prior surgeries demonstrated a lower rate of treatment success (P < .001). The main cause of failure was re-infection (11 of 28). Among cases failed for aseptic reasons (17 of 28), loosening of the cemented modular stem was the cause of re-revision in 2 patients (1.3%). ConclusionsThe use of modular cemented stems is a viable option in case of septic one-stage rTHA associated with severe femoral bone loss. However, surgeons and patients should be aware that this treatment is still characterized by a high rate of complications, which may lead to further surgeries. Level of evidenceIII.

Clinical and Radiographic Outcomes of a Monoblock Fluted Titanium-Tapered Stem for Paprosky IIIa, IIIb, and IV Femoral Bone Defects

BackgroundModern fluted titanium-tapered stems (FTTS) have been increasingly utilized to achieve primary stability in conversion and revision total hip arthroplasty with major femoral bone loss. This study sought to determine the radiographic and clinical outcomes of a monoblock FTTS in patients who had major femoral bone loss. MethodsA multicenter retrospective observational study of all total hip arthroplasty patients who received a monoblock FTTS who had up to 5-year radiographic follow-up was conducted. Only patients with femoral Paprosky classifications of IIIa, IIIb, and IV were included. Eighty-one monoblock FTTS were examined. Median clinical follow-up was 29 months (range, 18 to 58). Stem subsidence and loosening were assessed on most recent radiographs. All-cause revisions and stem survivals were assessed. ResultsMedian subsidence was 1.4 millimeters (mm) (range, 0 to 15.0). Sixteen (23.9%) and 3 (4.5%) stems had subsidence greater than 5 and 10 mm, respectively. All stems not acutely revised appeared stable, without evidence of loosening, at latest follow-up. Ten hips (12.3%) required reoperations. Of these, only 5 (6.2%) stems were removed; 4 due to periprosthetic joint infection and 1 for surgical exposure during acetabular revision. Kaplan–Meier analyses yielded an all-cause stem survivorship of 95.1% at 2-years and 87.1% at 4-years. Stem survivorships excluding septic causes was 98.8% at both 2 and 4 years. ConclusionMonoblock FTTS in complex femoral reconstruction cases showed encouraging clinical and radiographic results in patients who had severe femoral bone loss at median 29 months follow-up.

Two-stage revision for periprosthetic joint infection in cemented total hip arthroplasty: an increased risk for failure?

BackgroundThe impact of the prior fixation mode on the treatment outcome of chronic periprosthetic joint infection (PJI) of the hip is unclear. Removal of cemented total hip arthroplasty (THA) is particularly challenging and residual cement might be associated with reinfection. This study seeks to compare the results of two-stage revision for PJI in cemented and cementless THA.MethodsWe reviewed 143 consecutive patients undergoing two-stage revision THA for PJI between 2013 and 2018. Thirty-six patients with a fully cemented (n = 6), hybrid femur (n = 26) or hybrid acetabulum (n = 4) THA (cemented group) were matched 1:2 with a cohort of 72 patients who underwent removal of a cementless THA (cementless group). Groups were matched by sex, age, number of prior surgeries and history of infection treatment. Outcomes included microbiological results, interim re-debridement, reinfection, all-cause revision, and modified Harris hip scores (mHHS). Minimum follow-up was 2 years.ResultsCompared with PJI in cementless THA, patients undergoing removal of cemented THA had increasingly severe femoral bone loss (p = 0.004). Patients in the cemented group had an increased risk for positive cultures during second-stage reimplantation (22% compared to 8%, p = 0.043), higher rates of reinfection (22% compared to 7%, p = 0.021) and all-cause revision (31% compared to 14%, p = 0.039) compared to patients undergoing two-stage revision of cementless THA. Periprosthetic femoral fractures were more frequent in the group of patients with prior cementation (p = .004). Mean mHHS had been 37.5 in the cemented group and 39.1 in the cementless group, and these scores improved significantly in both groups (p < 0.01).ConclusionThis study shows that chronic infection in cemented THA might be associated with increased bone loss, higher rates of reinfection and all-cause revision following two-stage revision. This should be useful to clinicians counselling patients with hip PJI and can guide treatment and estimated outcomes.

Utilizing a Prefabricated Antibiotic-Impregnated Articular Spacer Combined With an Intramedullary Device for Significant Femoral Bone Loss in Periprosthetic Hip Infection.

Periprosthetic joint infection can be a devastating complication following total hip arthroplasty, which often requires a lengthy treatment course that is fraught with complications. There are various types of antibiotic-impregnated spacers that can be used to treat periprosthetic hip infections, with articulating spacers being utilized frequently with the goal of preserving patient range of motion and functionality. Many of these articulating spacers have pre-set sizes and stem options, which accommodate the majority of patients. However, when significant femoral bone loss is evident at the time of revision surgery, many articulating spacer options are not sufficient to provide stability, and custom modifications of available spacer constructs may be needed to fill the bony void. The goal of this article is to report a surgical technique that can be used in the salvage of failed antibiotic-impregnated spacers where severe femoral bone loss is present.

Revision total hip arthroplasty in patients with femoral bone loss using tapered rectangular femoral stem: a minimum 10 years' follow-up.

Revision total hip arthroplasty (THA) remains a significant challenge when there is severe femoral bone loss. The purpose of this study was to evaluate the clinical and radiographic outcomes of revision THA in patients with femoral bone loss treated with Zweymüller SLR-Plus stem. A retrospective review of 82 patients who underwent revision THA using tapered rectangular femoral stem between 1997 and 2007 was undertaken. Of the 82 patients, 9 patients were lost to follow-up and were excluded from the study. The most common reason for revision was aseptic loosening (92%), periprosthetic femur fracture (5%), and infection (3%). Bone loss was categorised preoperatively according to the Paprosky classification. The mean clinical follow-up was 14 years (range 10-19 years). Their mean age at the time of index surgery was 54.7 ± 15.3 (range 30-82) years. The mean Harris Hip Score was significantly improved at final follow-up (68.1 ±10.3) compared with that before the revision surgery (30.4 ± 7.7) (p < 0.0001). Of the 75 stems, 69 (92%) stems were radiographically stable at the last evaluation. Among the 69 stems, 64 hips (85%) had radiographic evidence of bone ingrowth and 5 (5%) had stable fibrous fixation of the stem. Among the 7 hips that were re-revised, 5 hips were re-revised for aseptic loosening, whereas 2 were re-revised for an infection. Kaplan-Meier survivorship analysis, with removal of the stem for any cause as the endpoint, revealed that the 15-year rate of survival of the components was 90% (95% CI, 0.83-0.97). Revision THA in patients with proximal femoral bone loss using Zweymüller SLR-Plus stem led to a high rate of osseointegration of the stem and good clinical results at long-term follow-up.

Antibiotic impregnated total femur spacers: a technical tip.

Simultaneous prosthetic joint infection of ipsilateral hip and knee arthroplasties is often accompanied by significant bone loss and presents a challenging reconstructive problem. Two-stage reconstruction is favored and requires the placement of a total femur spacer, which is not a commercially available device. We describe a surgical technique, reporting on 2 cases in which a customized total femur antibiotic impregnated spacer was created by combining an articulating knee spacer and an articulating hip spacer with a reinforced cement dowel construct connecting the 2 spacers. Custom total femoral spacers are useful in the management of infected femoral megaprostheses and cases with ipsilateral injected hip and knee arthroplasties and severe femoral bone loss.

Uncemented modular stems used for Vancouver B2 and B3 periprosthetic femoral fractures

Objective To evaluate the clinical outcome of Vancouver B2 and B3 periprosthetic femoral fractures treated with uncemented modular stems. Methods From September 2011 to April 2014, Twenty-four patients (12 males and 12 females, with the average age 63 years, ranging from 28 to 85 years) with periprosthetic femoral fractures (16 Vancouver B2 and 8 Vancouver B3) were treated with uncemented modular stems. Revision arthroplasty was conducted in all cases by using modular stems with 12 cerclage wirings and 11 great trochanter claw plates. One patient was treated with revision arthroplasty without additional fixations. Extended trochanter osteotomy was performed on 11 patients. Cortical strut allograft was used in 9 patients with severe femoral bone loss. Intraoperative complications including vascular or nerve injury and systemic complications including cardiovascular events, cerebrovascular events and deep vein thrombosis were recorded. Severe postoperative complications such as nonunion, re-fracture, periprosthetic joint infection and dislocation were recorded. The clinical outcome was evaluated by Harris score, Visual Analogue Score and Parker Mobility Score. The radiological outcome was taken to observe the healing status, stem subsidence and stability of the prosthesis. Results Two patients were lost to follow-up. Twenty-two patients were clinically followed-up. Radiological data was recorded in 16 patients. The average follow-up was 33 months (range, 12-68 months). All fractures healed within 6 months. The average Harris score improved from 4.0±1.1 preoperatively to 78.8±16.2 postoperatively (t= -20.195, P=0.000). The mean Parker Mobility Score improved from 0.5±0.9 preoperatively to 7.0±1.8 postoperatively (t=-14.835, P=0.000). The mean Visual Analogue Score decreased from 6.4±1.2 preoperatively to 2.0±1.5 postoperatively (t=10.879, P=0.000). No nonunion, infection or dislocation was found. One patient underwent re-operation because of re-fracture. Eight mm of prosthesis subsidence was observed in one case at 3 months postoperatively, and reached stable fixation at 6 months postoperatively without further subsidence. Conclusion Uncemented modular stems can achieve distal fixation and implant stability of periprosthetic femoral fractures while retaining optimal biomechanics of the hip. Assisted by femoral reconstruction techniques such as extended trochanter osteotomy, cortical strut allograft, great trochanter claw plates and cerclage wiring, revision arthroplasty using uncemented modular stems could realize optimal outcomes in treating Vancouver B2 and B3 periprosthetic femoral fractures. Key words: Arthroplasty, replacement, hip; Periprosthetic fractures; Femur; Reoperation; Prosthesis design

Porous-Coated Metaphyseal Sleeves for Severe Femoral and Tibial Bone Loss in Revision TKA

BackgroundMetaphyseal bone loss is commonly encountered in revision total knee arthroplasty (TKA). Anderson Orthopaedic Research Institute types 2 and 3 defects generally require some form of metaphyseal fixation or augmentation. This study evaluates the midterm results of stepped, porous-coated metaphyseal sleeves in revision TKA in the setting of severe bone loss. MethodsPatients who underwent revision TKA using metaphyseal sleeves from March 2006 to May 2014 at our institution were identified from a prospective research database. Preoperative patient characteristics and operative data were reviewed. Postoperative outcomes were compared with preoperative values. Primary study outcomes included complications, reoperations, radiographic assessment of sleeve osteointegration, and survivorship. ResultsOne hundred sixteen knees (108 patients) underwent revision TKA with 152 metaphyseal sleeves (111 tibial and 41 femoral). Anderson Orthopaedic Research Institute defect classification included 5 type 2A, 89 type 2B, and 17 type 3 tibial defects; and 3 type 2A, 34 type 2B, and 4 type 3 femoral defects. There were 3 intraoperative fractures (1.9%) associated with sleeve preparation and/or insertion. Six knees (5 patients) were lost to follow-up and 5 patients (6 knees) died before 2 years. Of the remaining 104 knees (98 patients, 134 sleeves), mean follow-up was 5.3 years (range 2-9.6 years). Nineteen knees (16.4%) required reoperation, most commonly for recurrent infection. Only one sleeve demonstrated radiographic evidence of failed osteointegration, but did not require revision. Two sleeves (1.5%) required removal and/or resection for recurrent infection. ConclusionThis large retrospective series illustrates the utility of porous metaphyseal sleeves in revision TKA with a low rate of intraoperative complications, excellent osteointegration, and long-term fixation.

Proximal femoral replacement in contemporary revision total hip arthroplasty for severe femoral bone loss: a review of outcomes.

Loss or absence of proximal femoral bone in revision total hip arthroplasty (THA) remains a significant challenge. While the main indication for the use of proximal femoral replacements (PFRs) is in the treatment of malignant disease, they have a valuable role in revision THA for loosening, fracture and infection in patients with bone loss. Our aim was to determine the clinical outcomes, implant survivorship, and complications of PFRs used in revision THA for indications other than malignancy. A retrospective review of 44 patients who underwent revision THA using a PFR between 2000 and 2013 was undertaken. Their mean age was 79 years (53 to 97); 31 (70%) were women. The bone loss was classified as Paprosky IIIB or IV in all patients. The mean follow-up was six years (2 to 12), at which time 22 patients had died and five were lost to follow-up. The mean Harris Hip Score improved from 42.8 (25.9 to 82.9) pre-operatively to 68.5 (21.0 to 87.7) post-operatively (p = 0.0009). A total of two PFRs had been revised, one for periprosthetic infection eight years post-operatively and one for aseptic loosening six years post-operatively. The Kaplan-Meier survivorship free of any revision or removal of an implant was 86% at five years and 66% years at ten years. A total of 12 patients (27%) had a complication including six with a dislocation. PFRs provide a useful salvage option for patients, particularly the elderly with massive proximal femoral bone loss who require revision THA, with significant clinical improvement. While the survivorship of the implant is good at five years, dislocation continues to be the most common complication. The judicious use of larger femoral heads, dual-mobility constructs, or constrained liners may help to minimise the risk of dislocation. Cite this article: Bone Joint J 2017;99-B:325-9.

Midterm Results of Porous Tantalum Femoral Cones in Revision Total Knee Arthroplasty

Severe bone loss during a revision total knee arthroplasty (TKA) remains a challenging problem. The purpose of this study was to determine the midterm clinical outcomes, fixation as evaluated radiographically, and survivorship of tantalum femoral cones used during revision TKAs in patients with severe femoral bone loss. From 2003 to 2011, 159 tantalum metaphyseal femoral cones were implanted in 157 patients at a single institution. Knee Society scores, radiographic results, and implant survivorship were analyzed. Two patients were lost to follow-up. Nineteen died of causes unrelated to the surgery but had been followed for >2 years and thus were included in the study. The mean age at the time of the index surgery was 64 years, and 82 patients were male. The mean duration of follow-up was 5 years (range, 2 to 10 years). The mean Knee Society score increased from 47 preoperatively to 65 at the most recent follow-up evaluation (p = 0.1). Radiographically, all 134 unrevised femoral cones were seen to be well fixed without any evidence of loosening. At 5 years, 23 cones had been revised: 14 because of infection, 6 because of aseptic loosening of the cone (all in hinged TKAs in patients with a Type-3 defect), and 3 because of ligamentous instability. The 5-year survivorship was 96% when the end point was revision of the cone due to aseptic loosening, 84% when it was revision of the cone for any reason, and 70% when it was any reoperation. In what we believe to be the largest series of such implants, femoral cones provided a durable and reliable option for metaphyseal fixation during revision TKA with severe femoral bone loss. Aseptic failure of the femoral cone was associated with use of a hinged TKA in a patient with a Type-3 bone defect. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Current concepts in total femoral replacement.

Total femoral replacement (TFR) is a salvage arthroplasty procedure used as an alternative to lower limb amputation. Since its initial description in the mid-20(th) century, this procedure has been used in a variety of oncologic and non-oncologic indications. The most compelling advantage of TFR is the achievement of immediate fixation which permits early mobilization. It is anticipated that TFR will be increasingly performed as the rate of revision arthroplasty rises worldwide. The existing literature is mainly composed of a rather heterogeneous mix of retrospective case series and a wide assortment of case reports. Numerous TFR prostheses are currently available and the surgeon must understand the unique implications of each implant design. Long-term functional outcomes are dependent on adherence to proper technique and an appropriate physical therapy program for postoperative rehabilitation. Revision TFR is mainly performed for periprosthetic infection and the severe femoral bone loss associated with aseptic revisions. Depending on the likelihood of attaining infection clearance, it may sometimes be advisable to proceed directly to hip disarticulation without attempting salvage of the TFR. Other reported complications of TFR include hip joint instability, limb length discrepancy, device failure, component loosening, patellar maltracking and delayed wound healing. Further research is needed to better characterize the long-term functional outcomes and complications associated with this complex procedure.

CORR Insights®: modular tapered implants for severe femoral bone loss in THA: reliable osseointegration but frequent complications.

CORR Insights®: modular tapered implants for severe femoral bone loss in THA: reliable osseointegration but frequent complications.

Modular tapered implants for severe femoral bone loss in THA: reliable osseointegration but frequent complications.

Modular tapered stems have been suggested as the optimal implants for patients with severe femoral bone loss (Paprosky Type IIIB and IV) undergoing revision total hip arthroplasty (THA); however, there are few data describing survivorship and hip scores associated with this treatment. At minimum 2 years, we sought to determine the (1) survivorship of these implants; (2) radiographic evidence of osseointegration; and (3) the Harris hip scores of patients revised with a modular tapered stem for severe femoral bone loss including the complications associated with their use. Between 1999 and 2010, we performed 1124 femoral revisions; of those, 135 (12%) were performed using a modular tapered stem. General indications for use of this device included bone loss, poor quality bone, leg length discrepancy, difficulty adjusting version, proximal femoral remodeling, and ectatic medullary canals in the setting of revision THA. This report reviewed 70 of those that were performed in Type IIIB and IV femurs. Of those 70 patients, 11 had died and one was lost before 2-year followup; the remaining 58 (83%, 33 with a Type IIIB femur and 25 with a Type IV femur) were followed for a minimum of 24 months (average, 67 months; range, 24-151 months). Survivorship free from revision, radiographic analysis for signs of subsidence or stem loosening, and Harris hip scores were tallied. One patient underwent stem revision for early subsidence followed by failure of ingrowth for a survivorship free from repeat revision of 98% (57 of 58 patients). Five other stems (for a total of six [10%]) subsided early but nonetheless achieved radiographic signs of ingrowth and were not revised again. All other stems demonstrated osseointegration without subsidence and remained radiographically well fixed. In patients with surviving implants, the mean Harris hip score improved from 34 (range, 11-49) preoperatively to 74 (range, 14-100; p<0.001) postoperatively. Overall, 15 of 58 patients (26%) experienced a complication, of whom 10 (17%) underwent reoperation. We found that modular tapered stems resulted in 98% survivorship at a mean of 67 months in patients with Type IIIB and IV femurs undergoing femoral revision, although the overall complication rate in this complex subset of patients is high. Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

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.

Three-Year Follow Up Utilizing Tantal Cones in Revision Total Knee Arthroplasty

There still is no consensus on the treatment of choice in revision knee arthroplasty associated with severe femoral and/or tibial bone loss. A total of 44 patients underwent revision knee arthroplasty procedures using porous tantalum cones (TM cones) to reconstruct tibial and/or femoral bone defects. At latest follow up after 37 months (32-48), 38 patients remained in the study. Tibial and femoral bone loss was categorized according to the AORI-Classification. The average preoperative KSS improved from 34 (range, 6-90) to 63 points (range, 7-90 points). The VAS improved from 7.5 to 4.8. Two patients required a re-revision due to aseptic loosening. There was no correlation between the different types of knee prosthesis implanted. Our study shows favourable clinical and radiological outcomes using TM cones in managing significant bone loss in revision total knee surgery.

Prevalence, Risk Factors, and Management of Proximal Femoral Remodeling in Revision Hip Arthroplasty

The prevalence of, risk factors, and management of proximal femoral remodeling in revision total hip arthroplasty is unknown. Therefore, we reviewed the files of 200 consecutive femoral revision arthroplasties to study this phenomenon. Remodeling was considered present if a properly sized diaphyseal-engaging acrylic template had appropriate distal canal fill but lied within 2mm of the proximal lateral endosteal cortex (definition 1) or completely outside the femoral canal (definition 2) on anteroposterior femoral radiographs. The prevalence of remodeling was 42% by definition 1 and 21% by definition 2. The strongest risk factors were loose femoral components and more severe femoral bone loss. Orthopedic surgeons performing revision arthroplasty should be prepared to encounter remodeling as its presence can complicate femoral component revision.