Free Vascularized Fibula Grafting for the Treatment of Osteonecrosis of the Femoral Head:

Modified trapdoor procedures using autogenous tricortical iliac graft without preserving the broken cartilage for treatment of osteonecrosis of the femoral head: a prospective cohort study with historical controls

Background

The aim of the present study was to investigate clinical and radiological outcomes of autologous tricortical iliac grafting performed through a window created at the femoral head without suturing the opened articular cartilage for the treatment of osteonecrosis of the femoral head (ONFH), called modified trapdoor procedures.

Materials and methods

A total of 59 consecutive patients (67 hips; 36 males and 23 females) with ONFH were included in this study, which was conducted from April 2009 to March 2012. Patients’ age ranged from 27 to 46 years old, with a mean age of 36.3 years. Harris hip scores (HHS) were used to evaluate hip function pre- and postoperatively. Anteroposterior and frog-position X-rays and magnetic resonance imaging (MRI) were conducted to assess lesion location, size, and ARCO stage. Clinical failure was defined as score < 80 points or treatment by total hip arthroplasty (THA). Radiographic failure was defined as a > 3 mm of collapse in the hip. This group was retrospectively matched according to the ARCO stage, extent, location, etiology of the lesion, average age, gender, and preoperative Harris hip score to a group of 59 patients (67 hips) who underwent the “light bulb” approach between March 2007 and April 2009.

Results

Mean follow-up was 91.2 ± 13.6 months (range, 75–115 months). Mean HHS was 91.3 ± 4.5, compared with 83.1 ± 4.5 in the “light bulb” cohort at the 6-year follow-up examination (P < 0.001). At the 6-year follow-up, for modified trapdoor procedures, five hips (8.5%) were classified as clinical failure, and three hips underwent total hip arthroplasty; seven hips were classified as (10.4%) radiographic failure. The clinical and radiographic failure of the hips treated with the modified trapdoor procedure was significantly lower compared to the hips treated with the “light bulb” procedure (P < 0.05). Survival of the joint was not significantly related to the location of the femoral head lesion between two groups; however, better clinical and radiographic results were observed in modified trapdoor procedures with size C and the ARCO stage III.

Conclusion

The present study demonstrated superior midterm clinical results in ONFH with the use of autologous tricortical iliac block graft through a femoral head window, without suturing the opened articular cartilage. The femoral head-preserving procedure was superior compared to the “light bulb” procedure treatment in patients with postcollapse osteonecrosis and large lesion.

Mid- to long-term results of modified non-vascularized allogeneic fibula grafting combined with core decompression and bone grafting for early femoral head necrosis

Purpose

The aim of this study was to determine mid-and-long term follow-up results of patients with early femoral head osteonecrosis who were treated by modified free vascularized fibular grafting combined with core decompression and bone grafting.

Methods

Forty-four patients at early ONFH were included in this study. Visual analog scale (VAS) pain scores, range of hip motion (ROM), and Harris hip score (HHS) were recorded to assess the clinical outcome; Western Ontario McMaster Osteoarthritis index (WOMAC) scores and Short Form 36 health survey (SF-36) were conducted to measure the living quality; X-ray film or magnetic resonance imaging (MRI) was used to evaluate radiographic progression; survivorship was defined as patients did not undergo the total hip arthroplasty (THA) or fusion at the last follow-up. Median follow-up was 7.4 years (6–8.2 years).

Results

The mean VAS score, ROM, and HHS were significantly improved at the final follow-up compared with preoperative values (p < 0.001). Health assessment including WOMAC scores and SF-36 were also better than those preoperatively (p < 0.001). Seven patients progressed to Ficat III and the four patients progressed to Ficat IV with osteoarthritis. Eight patients who cannot tolerate the pain and had poor living quality underwent THA.

Conclusion

Modified non-vascularized allogeneic fibula Grafting combined with core decompression and bone grafting could improve the clinical outcomes and enhance the quality of life for patients with early ONFH.

Joint-preserving procedures for osteonecrosis of the femoral head

Osteonecrosis of the femoral head is a poorly understood condition that may lead to progressive destruction of the hip joint. Its incidence is common between the third and fifth decades of life and it is the diagnosis behind 5–18% of annually performed total hip arthroplasties (THAs) in the USA.

Regarding the high rate of complications of THA in that age group, authors have agreed on the importance of joint-preservation techniques for this disease but techniques vary to establish a generally accepted algorithmic approach.

Surgical head-preserving procedures, core decompression with or without graft, stem cell augmentation, or biologic adjuncts, vascularized bone grafting, and proximal femoral osteotomies have all been published on with heterogeneous results and with limited evidence to date.

Consensus states that the prognosis of patients with osteonecrosis of the femoral head can be significantly improved with early diagnosis and timely intervention.

Cite this article: EFORT Open Rev 2019;4:647-658. DOI: 10.1302/2058-5241.4.180073

The effect of robot-navigation-assisted core decompression on early stage osteonecrosis of the femoral head

BACKGROUND

The aim of the current paper is to evaluate the effects of robot-navigation-assisted core decompression compared with conventional core decompression surgery for early-stage osteonecrosis of the femoral head.

METHODS

Twenty patients with a total of 36 hips who were diagnosed with Association Research Circulation Osseous stage 2 avascular necrosis of the femoral head and who received core decompression with or without robotic assistance were reviewed. The Harris hip score and visual analog scale score were used to assess clinical function. Intraoperative radiation exposure and operation time were used to evaluate the effectiveness of the robot-assisted system.

RESULTS

At a mean follow-up of 26.4 months (24-36 months), the Harris hip score, visual analog scale score, and survival rate of the patients were similar between the conventional and robot-assisted groups. The guidewire insertion time, number of guidewire attempts, and radiation exposure during guidewire insertion were all significantly lower in the robot-assisted group than in the conventional group.

CONCLUSIONS

Robot-assisted core decompression of the femoral head is as safe and effective as a conventional core decompression surgery. It can reduce operation time and decrease intraoperative radiation exposure.

Vascularized Fibular Grafting in Treatment of Femoral Neck Nonunion: A Prognostic Study Based on Long-Term Outcomes

BACKGROUND

The purpose of this study was to evaluate the long-term efficacy and prognostic factors predicting success of revision surgery with free vascularized fibular grafting (FVFG) for treatment of femoral neck nonunion.

METHODS

We prospectively enrolled patients who underwent revision surgery with FVFG between January 2001 and January 2013 in a tertiary hospital in China. A total of 98 patients with a minimum 5-year follow-up were included for analysis. The criteria for FVFG failure were conversion to hip arthroplasty, recommendation for a hip arthroplasty, or a Harris hip score of <80 points. Demographic information, the preoperative neck shortening ratio (NSR), the fixation method, and postoperative radiographic parameters including the postoperative NSR and neck-shaft angle (NSA) were recorded for prognostic analysis.

RESULTS

At an average of 9.8 ± 3.5 years (range, 3 to 17 years) postoperatively, the overall success rate of this surgical procedure was 77% (75 of 98). The success and failure groups had no significant differences in age, fixation method, interval between initial fixation and revision surgery, or postoperative NSA. The success group had a significantly higher NSR than the failure group both preoperatively (77.8% versus 62.4%, p < 0.001) and postoperatively (87.6% versus 78.4%, p = 0.001). The receiver operating characteristic (ROC) curve analysis revealed an optimal cutoff for preoperative NSR of 60% to predict the outcome. Patients with a preoperative NSR of >60% had a success rate of 91% (68 of 75).

CONCLUSIONS

Revision surgery with FVFG and internal fixation is an effective and important option for treating nonunion of the femoral neck in young patients without severe preoperative shortening and neck resorption (preoperative NSR of >60%).

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Total hip arthroplasty after failed transtrochanteric rotational osteotomy for osteonecrosis of the femoral head: A systematic review and meta-analysis

BACKGROUND

Several studies have reported regarding total hip arthroplasty (THA) for osteonecrosis of the femoral head after failed transtrochanteric rotational osteotomy (TRO). However, to our knowledge, no formal systematic review and meta-analysis have been published yet summarizing the clinical results of a THA after failed TRO. Therefore, we conducted a systematic review and meta-analysis of the THA outcomes after failed TRO. We focussed on the issue whether a previous TRO affects the results of subsequent THA, including operative time, operative blood loss, radiological parameters, postoperative complications, and clinical outcomes.

METHODS

Literatures published up to January 2018 were searched in the PubMed, Web of Science, and Cochrane Library, and the pooling of data was performed using a RevMan software (version 5.3, Cochrane Collaboration, Oxford, UK). A p-value<0.05 was considered statistically significant. We calculated the mean differences (MD) for continuous data and the odds ratio (OR) for dichotomous data with 95% confidence intervals (CI) for each outcome. Statistical heterogeneity was assessed based on I² using the standard Chi². When I²>50%, significant heterogeneity was assumed, and a random-effects model was applied for the meta-analysis. A fixed-effects model was applied in the absence of significant heterogeneity.

RESULTS

Five studies were included in this meta-analysis. The results showed that operative time was significantly longer in the THA after the TRO than that for the THA without previous osteotomy (I²=92%; MD=31.62; 95% CI: 5.95 to 57.28; p=0.02). Operative blood loss was significantly greater in the THA after the TRO than that in the THA without previous osteotomy (I²=71%; MD=123.30; 95% CI: 22.21 to 224.39; p=0.02). The rate of stem malalignment was significantly higher in the THA after the TRO than that in the THA without previous osteotomy (I²=0%; OR=5.23, 95% CI: 1.95 to 14.06; p=0.001). There was no significant difference in the dislocation rate (I²=0%; OR=2.12; 95% CI: 0.64 to 6.99; p=0.22), and the postoperative Harris hip score at the final follow-up (I²=75%, MD=-0.46, 95% CI: -3.92 to 3.01, p=0.80) between the groups.

CONCLUSION

The results demonstrate that, performing the THA after the TRO is technically more demanding than the THA without previous osteotomy. TRO does not affect the clinical results of future THA, and is a sufficient therapeutic alternative in younger patients.

LEVEL OF EVIDENCE

III, systematic and meta-analysis of case control studies.

Muscle pedicle bone grafting using the anterior one-third of the gluteus medius attached to the greater trochanter for treatment of Association Research Circulation Osseous stage II osteonecrosis of the femoral head

PURPOSE

The aim of this study was to evaluate the effectiveness of our technique on further collapse of the femoral head in Association Research Circulation Osseous (ARCO) stage II, patient's functional improvements, and analyze the survival rate of the affected hip.

METHODS

Between June 2007 and March 2015, 24 hips diagnosed with osteonecrosis of the femoral head (ONFH) were treated with our muscle pedicle bone grafting (MPBG) technique using anterior one-third of gluteus medius attached to the greater trochanter. The group was consisted of 15 men and eight women, mean age of 36 years at the time of surgery. Mean follow-up was 6.2 years.

RESULTS

Four hips showed regeneration, 11 hips showed no progression, and nine hips showed slight extent of the lesion. But during the follow-up, three hips underwent total hip arthroplasty at the mean follow-up of 5.8 years after the surgery. The survival rate at the last follow-up was approximately 87.5%. Excluding the three failed cases, the mean total Harris hip score was improved from 57.2 to 82.3 points (p < 0.05). We had no case of complications such as limping, numbness, wound infection, heterotopic ossification, nor intra- and post-operative fracture.

CONCLUSION

We showed 87.5% of survival rate by average of 6.2-year follow-up, maximum of 10.1 years. And compared to other reports, our technique showed relatively good results. In the short term, our modified MPBG technique seems to be effective in ARCO stage II ONFH. We, therefore, suggest this technique as one of the promising treatments of choices for patients with ARCO stage II ONFH.

Efficacy of autologous stem cell-based therapy for osteonecrosis of the femoral head in sickle cell disease: a five-year follow-up study

INTRODUCTION

Stem cell therapy with bone marrow-derived mononuclear cells (BMMCs) is an option for improving joint function in osteonecrosis of the femoral head (ONFH). Bone marrow-derived mesenchymal stromal cell (MSC) numbers and their osteogenic differentiation are decreased in patients with ONFH. However, whether this decrease also extends to the early stages of ONFH in sickle cell disease (SCD) is still unclear.

METHODS

We conducted a phase I/II, non-controlled study to determine efficacy and safety of BMMC implantation using a minimally invasive technique in SCD patients with ONFH. Eighty-nine patients were recruited and followed up for 60 months after surgery. Clinical and radiographic findings were assessed, and data were completed by in vitro analysis.

RESULTS

At the final follow-up (60 months) there was a significant improvement in clinical joint symptoms and pain relief as measured by the Harris Hip Score (P = 0.0005). In addition, after the BMMC implantation procedure, radiographic assessment showed disease stabilization and only 3.7 % of the treated patients did not achieve a satisfactory clinical result. The amount of fibroblast colony-forming units was 28.2 ± 13.9 per 1 million BMMCs after concentration. Flow cytometry analysis showed a significantly higher number of hematopoietic stem/endothelial progenitor cell markers in concentrated BMMCs when compared with bone marrow aspirate, indicating an enrichment of these cell types. Isolated MSCs from SCD patients with pre-collapse ONFH maintained the replicative capacity without significant loss of their specific biomolecular characteristics, multi-differentiation potential, and osteogenic differentiation activities. Cytokines and growth factors (interleukin-8, transforming growth factor-beta, stromal cell-derived factor-1alpha and vascular endothelial growth factor) that mediate endogenous bone regeneration were also produced by expanded MSCs from SCD patients.

CONCLUSION

The autologous BMMC implantation with a minimally invasive technique resulted in significant pain relief and halted the progression of early stages of ONFH in SCD patients. MSCs from SCD patients display biological properties that may add to the efficiency of surgical treatment in ONFH. In summary, our results indicate that infusion of BMMCs enriched with stem/progenitor cells is a safe and effective treatment for the early stages of ONFH in SCD patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02448121; registered 15 May 2015.

Free vascularised fibular grafts in orthopaedics

Bony defects caused by trauma, tumors, infection or congenital anomalies can present a significant surgical challenge. Free vascularised fibular bone grafts (FVFGs) have proven to be extremely effective in managing larger defects (longer than 6 cm) where other conventional grafts have failed. FVFGs also have a role in the treatment of avascular necrosis (AVN) of the femoral head, failed spinal fusions and complex arthrodeses. Due to the fact that they have their own blood supply, FVFGs are effective even in cases where there is poor vascularity at the recipient site, such as in infection and following radiotherapy. This article discusses the versatility of the FVFG and its successful application to a variety of different pathologies. It also covers the applied anatomy, indications, operative techniques, complications and donor-site morbidity. Though technically challenging and demanding, the FVFG is an extremely useful salvage option and can facilitate limb reconstruction in the most complex of cases.

The efficacy of targeted intraarterial delivery of concentrated autologous bone marrow containing mononuclear cells in the treatment of osteonecrosis of the femoral head: a five year follow-up study

OBJECTIVE

To investigate the efficacy and safety of targeted delivery of autologous bone marrow mononuclear cells (BMMCs), which are highly enriched with mesenchymal stem cells (BMMSCs), via medial circumflex femoral artery in the treatment of osteonecrosis of the femoral head (ONFH).

METHODS

62 patients (78 hips) with ONFH were recruited in this study. All of these patients were treated with BMMCs perfusion via medial circumflex femoral artery. The concentrated BMMCs (30-60ml) were gained from autologous bone marrow (100-200ml) harvested from anterior iliac crest and then were intra-arterially perfused into the femoral head. Ficat stage was used to classify the radiological stage of ONFH. Harris hip score was used to evaluate the clinical symptoms of osteonecrosis. Ficat stage and Harris hip scores were assessed at onset of treatment at 6, 12, 24, 36, 48 and 60months after the initial treatment. Total hip arthroplasty (THA) was also assessed as an endpoint at each follow-up.

RESULTS

A follow-up on the patient was done at the end of five years, and 92.31% (72 of 78) of hips achieved a satisfactory clinical result while only 6 hips (7.69%) progressed to clinical failure and required THA. Radiological progression was noted in 34 of 78 hips (43.59%); the overall rate of collapse was 38.24% (26 of 68 hips) in stage-I and stage-II hip combinations and 12.5% (2 of 16) in stage-I hips and 46.15% (24 of 52) in stage-II hips. The mean time of conversion to THA was 3years (1 to 5years) and the average time to collapse were 3.5years (1-5years). The mean Harris hip score increased from 59 points at baseline to 75 points at 12months, 82 points at 24months, 81 points at 36months, 79 points at 48months and 74 points at 60months. Five years after the treatment, 3 of 10 hips (30%) in stage-III had deteriorated to clinical failure whereas only 3 of 68 hips (4.41%) in stage-I and II combination had progressed to clinical failure (p<0.05). Kaplan-Meier survival analysis showed a significant difference in the time to failure between the pre-collapse hips (Ficat stage-I and II) and the post-collapse hips (Ficat stage-III) at five years follow-up (Log-rank test; p<0.01). No complication was found in any patients.

CONCLUSIONS

Autologous BMMSC perfusion via the medial circumflex femoral artery can relieve symptoms, improve hip function and delay the progression of ONFH. The clinical outcome is better when it is applied prior to the collapse. This work demonstrates that autologous BMMSC perfusion via the medial circumflex femoral artery is a safe, effective and minimally invasive treatment strategy for early-stage ONFH.

Treatment of osteonecrosis of the femoral head by using the greater trochanteric bone flap with double vascular pedicles

The use of the bone flap transfer has been reported to be successful in treatment of patients with early to medium stage (Ficat and Arlet stage I-III) osteonecrosis of the femoral head (ONFH). We examined the vascular anatomy and blood supply of the greater trochanter area and evaluated the feasibility of revascularization of the femoral head by using the bone flap pedicled with transverse and gluteus medius branches of the lateral circumflex femoral artery. Based on the anatomy study, from January 2002 to May 2004, 32 ONFH patients were treated with the greater trochanteric bone flap pedicled with double blood vessels. Fifteen femoral heads were Ficat and Arlet stage II and 17 were stage III. The mean follow-up was 99.5 months. Two of the 32 patients required a total hip replacement due to severe hip pain after surgery. The overall Harris hip score improved from a mean of 55.2 points to 85 points. Our data suggest the procedure is relatively easy to perform, less donor-site morbidity and useful for young patients with stages II to III disease with or without mild collapse of the femoral head.

Unilateral free vascularized fibula shared for the treatment of bilateral osteonecrosis of the femoral head

Between June 2007 and May 2008, 21 patients with bilateral osteonecrosis of the femoral head were surgically treated with implantation of free vascularized fibula obtained from the unilateral donor site. All patients were followed up clinically and radiographically for an average of 3.5 years. The evaluation included operative duration, blood loss, Harris hip score, incidence of complications, and radiological examinations. The time for fibular harvesting was 20min on average. Total operative duration was 100-240min, with an average of 150min. Blood loss averaged 300ml. All transplanted fibula integrated well to the femoral head 3.5years postoperatively with no severe complications observed. The results revealed that unilateral free vascularized fibula is effective for the treatment of bilateral osteonecrosis of the femoral head.

Vascularized fibular grafts in patients with avascular necrosis of femoral head: a systematic review and meta-analysis

BACKGROUND

Vascularized fibular grafting (VFG) has been initiated to treat avascular necrosis of the femoral head (ANFH) since the late 1970s. There are a number of review articles updating the use of VFG to treat the ANFH. None of them applied statistical analysis for combining results from different studies to obtain a quantitative estimate of the overall effect and potential harm of VFG in comparison to other treatment.

METHODS

Several electronic databases were searched to find studies using VFG to treat ANFH. The outcomes sought included Harris Score, failure rate (conversion to total hip arthroplasty (THA) and/or femoral head collapse), and complications rate. Included studies were assessed for methodological bias and estimates of effect were calculated. Potential reasons for heterogeneity were explored.

RESULTS

The clinical results of 69.0 % of VFG-treated patients and 25.0 % of non-VFG-treated patients were good to excellent (OR 0.13; p < 0.01). The conversion rate to THA of VFG-treated and that of other methods treated hips was 16.5 % and 42.6 % (OR 0.19; p < 0.001). Collapse rate of VFG-treated and that of non-VFG-treated hips was 16.7 % and 63.6 % (OR 0.09; p < 0.05). The complication rate of VFG-treated and that of other methods treated patients was 23.8 % and 8.9 % (OR 3.44; p = 0.09). For Steinberg stage I, II ANFH, failure rate of VFG-treated and that of non-VFG-treated hips was 9.8 % and 40.2 % (OR 0.17; p < 0.001). For Steinberg stage II, III ANFH, failure rate of VFG-treated and that of non-VFG-treated hips was 16.5 % and 42.8 %, respectively (OR 0.17; p < 0.001).

CONCLUSIONS

VFG is a justified method that can prevent the ANFH from progressing to collapse, and that can retard or avoid hip replacement, especially in the hips of Steinberg stage I, II, and III.

Femoral head osteonecrosis: why choose free vascularized fibula grafting

Osteonecrosis of the femoral head is a disease in which bone death occurs and usually progresses to articular incongruity and subsequent osteoarthritis. To delay the process of the disease and the conversion to total hip arthroplasty, many surgical techniques have been described. Core decompression, nonvascularized autologous bone grafts, porous tantalum implant procedure, and various osteotomies have been used for the management of early precollapse stage osteonecrosis of the femoral head. However, none of these procedures is neither entirely effective nor can obtain predictable results. With the progress of microsurgery, the implantation of a free vascularized fibula graft to the necrotic femoral head has provided the most consistently successful results. Although the procedure is technically demanding, there is growing recognition that the use of free vascularized fibula graft may improve patient quality of life by functional improvement and pain alleviation. The success of the procedure is related to decompression of the femoral head, excision of the necrotic bone, and addition of cancellous bone graft with osteoinductive and osteoconductive properties, which augments revascularization and neoosteogenesis of the femoral head. Free vascularized fibula graft, especially in younger patients, is a salvaging procedure of the necrotic femoral head in early precollapse stages. In postcollapse osteonecrosis, the procedure appears to delay the need for total hip arthroplasty in the majority of patients. The purpose of this review article is to update knowledge about treatment strategies in femoral head osteonecrosis and to compare free vascularized fibula grafting to traditional and new treatment modalities.

Effect of a porous tantalum rod on early and intermediate stages of necrosis of the femoral head

The aim of this study was to evaluate the effect of a porous tantalum rod implant for the treatment of early femoral head necrosis. From April 2007 to June 2009, a total of 35 femoral head necrosis patients (with 49 hips) were treated with core decompression in combination with the insertion of a porous tantalum rod. The mean age was 38.2 years (22-50 years) and the mean follow-up period was 15.2 months (12-36 months). The surgical time and blood loss were recorded. The Harris hip scores and radiological results were adopted for evaluation. The mean surgical time was 35 min, and the mean blood loss was 50 ml. The mean Harris score improved from 48.3 ± 3.2 preoperative to 83.7 ± 4.1 at the last follow-up (p < 0.05). Eight affected hips exhibited progressive pain including three hips that progressed to femoral collapse, and one revision followed by total hip arthroplasty (THA). For the patient who underwent revision and THA, the articular cartilage surface was seen to be damaged and fragmented. High-density metal particle residuals were observed on radiograph in the bone channel and femoral marrow cavity. We conclude that the selection criteria for porous tantalum implants should be early and intermediate stages of femoral head necrosis. Further study is warranted to reveal whether the metal particles released play a role in the progression of pain and failure.

Partial resurfacing with varus osteotomy for an osteochondral defect of the femoral head

Osteochondral defects of the femoral head represent a major challenge and various modern treatment options exist. We report a 16-year-old male with a large (3 x 3 cm) osteochondral defect of the femoral head that was treated with a partial resurfacing prosthesis combined with a high varus osteotomy, performed by surgical dislocation of the hip. Two years after surgery the patient was progressing well without complications.

To study the role of dynamic magnetic resonance imaging in assessing the femoral head vascularity in intracapsular femoral neck fractures

Intracapsular femoral neck fractures remain unsolved fractures even after improvement in techniques of diagnosis and internal fixation. Individuals who sustain displaced femoral neck fractures are at high risk of developing avascular necrosis and non-union. Although several methods for predicting the viability of femoral head have been reported, they are not effective or widely used because of unreliability, potential complications and technical difficulties. Dynamic MRI was introduced in the recent past as a simple, non-invasive technique to predict the femoral head viability after the femoral neck fractures. In this study role of dynamic MRI was studied in 30 patients with 31 intracapsular femoral neck fractures. Fractures were divided in to three types according to dynamic curve patterns on MRI evaluation and were followed up for 6 months to 2 years to observe the final outcome. Sensitivity, Specificity and the Accuracy of dynamic MRI in predicting vascularity after femoral neck fracture are 87%, 88% and 87%, respectively. Type A or Type B curve pattern is a positive factor to successful osteosynthesis with p value <0.0001 (Chi-square test). This is a statistically significant value. From this finding it can be suggested that the reliability of dynamic curves A and B in predicting maintained vascularity of femoral head is high. This investigation can be used to predict the vascularity of femoral head after intracapsular femoral neck fractures. There was a good correlation between the outcomes of fractures and dynamic MRI curves done within 48 h of injury. This signifies the role of dynamic MRI in predicting the vascularity of femoral head as early as 48 h. A treatment algorithm can be suggested on the basis of dynamic MRI curves. The fractures with Type C dynamic curve should be considered as fractures with poor vascularity of femoral head and measures to enhance the vascularity of femoral head along with rigid internal fixation should be undertaken to promote revascularization process and better healing of fractures. Patients with these fractures should be on longer non-weight bearing ambulation than other patients. To conclude, the dynamic MRI seems to be reliable, non-invasive, sensitive, specific and accurate method of assessing the femoral head vascularity after intracapsular femoral neck fractures as early as 48 h of injury and to predict the outcome of fractures and may be used as a guideline for management of intracapsular femoral neck fractures.

Vascularised fibular graft in the management of femoral head osteonecrosis: twenty years later

The management of osteonecrosis of the femoral head ranges from symptomatic therapy to total hip replacement. Conservative treatment is effective only in small, early-stage lesions. Free vascularised fibular grafting has provided more consistently successful results than any other joint-preserving method. It supports the collapsing subchondral plate by primary callus formation, reduces intra-osseous pressure, removes and replaces the necrotic segment, and adds viable cortical bone graft plus fresh cancellous graft, which has osseoinductive and osseoconductive potential. Factors predisposing to success are the aetiology, stage and size of the lesion. Furthermore, it is a hip-salvaging procedure in early pre-collapse stages, and a time-buying one when the femoral head has collapsed.

Subtrochanteric fracture after free vascularised fibular grafting for osteonecrosis of the femoral head

The aim of this study was to determine the incidence and factors associated with subtrochanteric fracture after free vascularised fibular grafting for osteonecrosis of the femoral head, and to analyse clinical and radiological outcomes of open reduction and internal fixation. From April 1991 to May 2004, eight such fractures were managed by Rowe plate fixation. Factors examined included age, gender, side of operation, cause and preoperative and postoperative stage of osteonecrosis, and preoperative and postoperative functional assessment. The osteonecrosis was caused by alcohol consumption in six, steroid use in one and was idiopathic in one case. The overall incidence of fracture was 4.1% (13.9% in bilateral operations) and all occurred in men of mean age 36.3 years, were induced by low-energy injury and were attributed to defects created in the lateral femoral cortex for graft placement. Seven of the eight fractures (87.5%) developed within 12 weeks and all fractures healed at a mean of 16.6 weeks after internal fixation. No major complications occurred and no significant differences were found in clinical or radiological results between the fracture and non-fracture groups. Our findings indicate that strict education and mandatory protection from full weight bearing are required for 12 weeks after free vascularised fibular grafting for osteonecrosis of the femoral head.

Autogenous osteochondral transfer in the femoral head after osteonecrosis

Osteonecrosis of the femoral head is a major problem, especially in younger patients. Most of them need a total hip replacement. This article presents a case of a successful autologous osteochondral transfer.

Subchondral fracture of the femoral head in healthy adults

Subchondral fracture of the femoral head has been reported to occur as an insufficiency fracture associated with poor bone quality or as a fatigue fracture in young military recruits. Transient osteoporosis of the hip has clinical and imaging findings that resemble those of a subchondral fracture, but it usually occurs in healthy middle-aged people not involved in sports or similar activities. The clinical aspects of five cases of subchondral fracture of the femoral head occurring in four healthy adults without antecedent trauma were evaluated. Of particular interest were whether subchondral fracture of the femoral head could occur without a sudden increase in daily activity and what differences could be detected from the imaging and clinical courses between subchondral fracture of the femoral head and transient osteoporosis of the hip. Three cases of subchondral fracture of the femoral head occurred without an increase in daily activity. The only difference in imaging findings between subchondral fracture of the femoral head and transient osteoporosis of the hip was the existence of a subchondral fracture line seen on magnetic resonance images of a subchondral fracture of the femoral head. The clinical courses of these disorders were similar. These findings suggest transient osteoporosis of the hip and subchondral fracture of the femoral head are subchondral bone injuries of different severity.

LEVEL OF EVIDENCE

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

Indications for free vascularized fibular grafting for the treatment of osteonecrosis of the femoral head

Background

The present study aimed to determine the indications for free vascularized fibular grafting for the treatment of osteonecrosis of the femoral head.

Methods

Seventy-one hips (60 patients) were clinically followed for a minimum of 3 years. Average follow-up period was 7 years. Etiologies were alcohol abuse in 31 hips, steroid use in 27, idiopathic in 7 and trauma in 6. Preoperative staging of the necrotic lesion was done using the Steinberg's classification system. The outcomes of free vascularized fibular grafting were determined clinically using the Harris hip-scoring system, radiographically by determining progression, and survivorship by lack of conversion to total hip replacement.

Results

The average preoperative Harris hip score was 56 points and the average score at the latest follow-up examination was 78 points. Forty-seven hips (67%) were clinically rated good to excellent, 4 hips (6%) were rated fair, and 20 hips (28%) were rated poor. Thirty-six hips (51%) did not show radiographic progression while 35 hips (49%) did, and with an overall survivorship of 83% at 7 years. Steroid-induced osteonecrosis was significantly associated with poor scores and survival rate (68%). Preoperative collapse was significantly associated with poor scores, radiographic progression and poor survival rate (72%). A large extent of osteonecrosis greater than 300 degrees was significantly associated with poor scores, radiographic progression and poor survival rate (67%). There was no relationship between the distance from the tip of the grafted fibula to the subchondral bone of the femoral head and postoperative radiographic progression.

Conclusion

In conclusion, small osteonecrosis (less than 300 degrees of the femoral head) without preoperative collapse (Steinberg's stages I and II) is the major indication for free vascularized fibular grafting. Steroid-induced osteonecrosis is a relative contraindication. Large osteonecrosis (greater than 300 degrees) with severe preoperative collapse (greater than 3 mm) is a major contraindication. Hips with 2 negative factors such as severe preoperative collapse and a large extent of osteonecrosis, require hip replacements.

Free vascularized fibular grafting following failed core decompression for femoral head osteonecrosis

The results of treatment of femoral head osteonecrosis with free vascularized fibular grafting (FVFG) following failed core decompression (core decompression-FVFG [CD-FVFG] group: 32 hips) were reviewed and compared with those of a control group that underwent FVFG only (54 hips). Outcome was considered unsuccessful if total hip arthroplasty was subsequently performed. Total hip arthroplasty was performed in 15 and 20 hips of the CD-FVFG and control groups, respectively. When considering age, sex, and presence of bilateral disease, patients with previous core decompression did not have a significantly different failure rate from patients with FVFG only. However, patients with preoperative stage V osteonecrosis or corticosteroid use had worse outcomes after vascularized fibular grafting if they had a previous core decompression of the femoral head.

Osteonecrosis of the femoral head: etiology, imaging and treatment

Osteonecrosis of the femoral head is a disabling clinical entity affecting young adults that usually leads to destruction of the hip joint. A high index of suspicion is necessary for the diagnosis due to the insidious onset of the bone infarcts and the lack of specific clinical signs at the early stages. Many etiology-associated factors have been identified reducing thus the number of idiopathic cases. A number of joint salvaging treatment options are available if early diagnosis can be achieved. MR imaging has been proved to be a highly accurate method both for early diagnosis and for staging of the disease. Replacement of the hip joint is the last resort for pain relief and function, although non-desirable because of the young age of the affected population.

Treatment of avascular necrosis of the hip by a non-vascularised cortical graft

This retrospective study describes the long-term results of core decompression and placement of a non-vascularised bone graft in the management of avascular necrosis of the femoral head. We treated 80 hips in 65 patients, 18 by a cortical tibial autograft and 62 by a fibular allograft. The mean age of the patients was 36 years (SD 13.2). A total of 78 hips were available for evaluation of which pre-operatively six were Ficat-Arlet stage 0, three stage I, 31 stage IIA, 16 stage IIB, 13 stage III and nine stage IV. A total of 34 hips (44%) were revised at a mean of four years (SD 3.8). Survivorship analysis using a clinical end-point showed a survival rate of 59% five years after surgery. We found a significant difference (p = 0.002) in survivorship, when using a clinical and radiological end-point, between the two grafts, in favour of the tibial autograft. We considered this difference to be the result of the better quality and increased volume of tibial bone compared with that from the trochanteric region used with the fibular allograft. This is a relatively simple, extra-articular and reproducible procedure. In our view core decompression, removal of the necrotic tissue and packing of the cancellous grafts into the core track are vital parts of the procedure.

Total hip arthroplasty after failed transtrochanteric rotational osteotomy for avascular necrosis of the femoral head

We compared the clinical and radiographic outcome of 15 hips converted to total hip arthroplasty after failed transtrochanteric rotational osteotomy (THA after TRO) for avascular necrosis of the femoral head (ANFH) with that of a matched control group of 16 hips with primary THA for ANFH. The operating time in THA after TRO was significantly longer than that in primary THA. Perioperative blood loss in THA after TRO was significantly more than that in primary THA. Postoperative complications were observed in 4 hips of THA after TRO. The Harris Hip Score, the stability of implants, and survival rates did not significantly differ in both groups. We conclude that TRO did not influence the outcome of secondary THA at short- and middle-term follow-up.

Treatment of osteonecrosis of the femoral head with core decompression and human bone morphogenetic protein

A retrospective evaluation was done of 15 patients (17 hips) with symptomatic osteonecrosis of the hip treated with core decompression combined with an allogeneic, antigen-extracted, autolyzed fibula allograft and 50 mg of partially purified human bone morphogenetic protein and noncollagenous proteins. The average duration of clinical followup of the patients was 53 months (range, 26-94 months). The osteonecrotic involvement of the hip was classified by plain radiographs using a modification of the Ficat staging system and MRI evaluations. Fifteen hips were classified as Ficat Stage IIA, one hip (one patient) was classified as Ficat Stage IIB, and one hip (one patient) was classified as Ficat Stage III. Fourteen hips had involvement of 50% or less of the femoral head and 2/3 or less involvement of the weight-bearing surface of the femoral head, based on a magnetic resonance imaging evaluation. The procedures were a clinical success in 14 of 15 hips (93%; 13 patients) with Stage IIA disease. Three of 17 hips (three patients) had radiographic progression (Ficat Stages IIA, IIB, and III) of the femoral head and were converted to total hip replacements. Only one of seven hips (six patients) with 50% or less involvement of the femoral head and between 1/3 and 2/3 of the weightbearing surface of the femoral head developed radiographic progression of the femoral head. There was no radiographic progression in the 3 hips with less than 1/3 involvement of the weightbearing surface of the femoral head. Further evaluation of the potential efficacy of bone morphogenetic protein is required in randomized trials.

Évolution anatomo-radiographique des nécroses avasculaires de la tête fémorale traitées par transplant fibulaire vascularisé

PURPOSE OF THE STUDY

We report our experience with vascularized fibular transplant using the technique described by Urbaniak for the treatment of avascular necrosis of the femoral head.

MATERIAL AND METHODS

Sixteen patients, mean age 39 years 4 months at surgery, were evaluated at mean 3 years 6 months follow-up (minimum 15 months). Mean pain score (analog visual scale) was 6.25/10. Mean Postel-Merle-d'Aubigné (PMA) function score was 12. The Ficat classification was grade 2A (n=9) or grade 2B (n=7).

RESULTS

There were no cases of infection or migration of the fibula. The only complication at the donor site was one case of paresia of the long extensor of the hallux which resolved spontaneously. There were five failures which required a hip prosthesis (31%). Three failures occurred early during the first 18 months. Two were late. These patients had grade 2B (n=4) or grade 2A (n=1) necrosis. At last follow-up, eleven hips had not required prosthetic revision (69%). The pain score improved in 81% of patients: mean score=2.3. Nine patients were satisfied or very satisfied (81%). Among these eleven hips, function was good or excellent in eight (72%). Walking distance was improved in nine patients, unchanged in one and worse in one. Joint motion improved in nine patients, was unchanged in one and decreased in one. Nine patients resumed their full-time job. Mean sick leave was 13.3 months. Radiographically, only two of the initial Ficat grade 2A hips remained at this stage. Likewise only one of the three hips initially rated grade 2B remained at this stage. Overall radiographic results were: failure (n=5), worsening (n=9), stabilization and no improvement (n=2). Among the nine 2A hips, one was converted to a total hip prosthesis and five femoral heads remained spheric. Among the seven 2B hips, four were converted to a total hip prosthesis and two femoral heads collapsed.

DISCUSSION

At mean follow-up (3.5 years), 69% of the hips had not required total hip arthroplasty. The grade 2A hips did better but the small sample size did not allow statistical comparison. There was a clear discordance between the clinical presentation and the radiographic findings among the hips which were not treated with a prosthesis: good function score, maintained occupational and daily life activities contrasting with unfavorable radiographic evolution. Results could be improved by detailed quantification of the lesion using 3D imaging and by associating intraoperative navigation.

Pathologic conditions mimicking osteonecrosis

MRI has become increasingly helpful in establishing an early diagnosis of avascular necrosis(AVN). AVN often demonstrates a classic pattern on MRI; findings earlier in the course of the disease are less specific. Many pitfalls can complicate interpretation, and a number of pathologic conditions can share features of early AVN on MRI and plain radiographs. These entities should be distinguished from AVN, because treatment and prognosis may differ significantly.

Results of free vascularized fibular grafting for femoral head osteonecrosis in patients with systemic lupus erythematosus

Osteonecrosis of the femoral head is a known complication of systemic lupus erythematosus. Patients often require surgical intervention at an early age. Options include total hip arthroplasty, core decompression, and free vascularized fibular grafting. Because these patients are usually young, any procedure that avoids total hip arthroplasty, especially if it does not make joint replacement more difficult, would be most desirable. Free vascularized fibular grafting is an effective method of treating osteonecrosis of the femoral head. Inpatients with lupus erythematosus, results of free vascularized fibular grafting at a minimum 2-year follow-up are similar to those in patients without a diagnosis of lupus.

Management of Ficat stage III and IV osteonecrosis of the hip

Management of Ficat stage III and IV osteonecrosis of the hip remains controversial. Because patients usually require a surgical intervention in their mid 30s, the initial procedure is often the first step in a lifelong treatment plan. Long-term results of total hip arthroplasty in these young, active patients have been disappointing. New alternative bearing surfaces (metal-on-metal, ceramic-on-ceramic, and highly cross-linked polyethylene) and improved methods of fixation may lead to better long-term results. Nevertheless, bone- and joint-preserving procedures, such as free-vascularized fibular graft, trapdoor grafting, redirectional osteotomy, or hemiresurfacing hip arthroplasty, should be considered. The choice of option depends on patient age, the cause of osteonecrosis, the extent of femoral head involvement, and the condition of the acetabular articular cartilage. The goals of treatment are to relieve pain, improve function, minimize morbidity, and maintain options for secondary procedures.

VEGF-promoted surgical angiogenesis in necrotic bone

The ability of vascular endothelial growth factor (VEGF) to accelerate neoangiogenesis from implanted arterovenous (AV) bundles in necrotic bone was evaluated. A saphenous AV bundle was placed in a necrotic segment of rabbit ilium. In group II, VEGF (100 ng/h x 3 days) was administered by continuous infusion. Bone blood flow was measured with radioactive-labeled microspheres, and capillary density was determined by microangiography combined with Spälteholtz bone clearing at 1, 2, and 4 weeks. Neovascularization was observed along the implanted vascular bundle in both groups. One week after surgery, bone blood flow and vessel area were significantly higher in VEGF-treated animals (P < 0.05). No significant difference was observed at later times. Direct VEGF administration increased surgical angiogenesis and improved blood flow and neovascularization in necrotic bone 1 week after AV bundle implantation. Thereafter, a robust angiogenic response from the AV bundle was seen in both groups.

Impact of implant design on femoral head hemiresurfacing arthroplasty

Two consecutive series of cemented femoral hemiresurfacing arthroplasty for patients with Ficat Stage III and early Stage IV osteonecrosis of the femoral head were studied to identify the impact of design on the clinical and radiographic results. Group I (30 patients, 33 hips) components had a cobalt chrome shell with a tapered inner dimension, no stem, and sizes in 2-mm increments. Group II (37 patients, 51 hips) components differed by adding a proportional stem, increased spherical coverage, and sizes in 1-mm increments. The average age for the patients in both groups was 40 years. Fifty percent of the patients in Group I were men: in 43% of patients osteonecrosis was associated with steroid use and in 21% of patients it was associated with alcohol use. Thirty-three percent of the patients in Group II were men: in 41% of patients osteonecrosis was associated with steroid use and in 17% of patients it was associated with alcohol use. The average followup is 42 months for Group I and 24 months for Group II. Neither group experienced infections, nerve palsies, dislocations, or loosening. In Group I, two patients died of unrelated causes and five patients had reoperations, two for femoral neck fractures, and three for unsatisfactory pain relief. No patients in Group II had femoral neck fractures but three patients had reoperations for unsatisfactory pain relief. The stemmed component in Group II has resulted in an improvement in component position and elimination of femoral neck fractures in this series.

Treatment of avascular necrosis of the femoral head with vascularized fibular transplant

Two hundred twenty-eight hips in 187 patients with avascular necrosis of the femoral head were treated with vascularized fibular transplant from March 1989 to March 2000. The etiologic factors associated with the disease included corticosteroids in 84 patients (44%; 101 hips, trauma in 25 patients (13%; 29 hips), alcohol abuse in 24 patients (12%; 28 hips), and 41 hips (18%) were classified as idiopathic. Systemic disorders, including systemic lupus erythematosus, sickle cell anemia, inflammatory bowel disease, pregnancy, and dysbaric disease were observed in 12, nine, four, three, and one hip(s), respectively. Of the 228 hips operated on, 184 hips (152 patients) were assessed postoperatively with followup ranging from 1 to 10 years (mean, 4.7 years). Using the Steinberg classification system, 39 hips (21%) were in Stage II; 45 hips (25%) were in Stage II; 77 hips (42%) were in Stage IV; and 23 hips (12%) were in Stage V. Of the 184 hips treated, 101 (54%) remained stable postoperatively, whereas 69 (38%) had progression, and 14 hips (8%) were converted to total hip arthroplasty. Of the 69 hips that had progression, 44 (64%) did not progress until 6 to 10 years after the procedure, whereas 25 (36%) progressed within the first 5 years postoperatively. The best results were obtained in patients with Stage II osteonecrosis in whom 95% of the hips did not progress postoperatively. In contrast, only 39% of the hips in patients with Stage V osteonecrosis remained stable. Preoperative and postoperative clinical evaluation using the Harris hip score showed an increase from 85 to 96 points in hips with Stage II disease; from 74 to 91 points in hips with Stage III disease; from 69 to 85 points in hips with Stage IV disease; and from 61 to 76 in hips with Stage V disease. The current results show that the vascularized fibular graft is an excellent procedure for the precollapse stages and a valuable alternative for patients with Stages III, IV, and V of the disease.

Classification of osteonecrosis of the femoral head. Reliability, reproducibility, and prognostic value

The purpose of the current investigation was to determine interobserver and intraobserver reliability of the classification system of Steinberg et al for osteonecrosis of the femoral head. Sixty-five anteroposterior and lateral radiographs of hips were selected randomly from a pool of patients with confirmed osteonecrosis of the femoral head. Six fellowship-trained observers viewed the radiographs (Reading 1). The observers used six main stages of the classification excluding A, B, and C subgroups. The same observers viewed the radiographs 4 months later in reverse order (Reading 2). Reading 1 was used to calculate interobserver kappa values. Reading 2 was used to calculate intraobserver kappa values. Stage-specific kappa values for interobserver variation between all viewers were as follows: Stage I, k = 0.64; Stage II, k = 0.51; Stage III, k = 0.21; Stage IV, k = 0.49; Stage V, k = 0.36; and Stage VI, k = 0.80. Stage-specific kappa values for intraobserver variation between all viewers were as follows: Stage I, k = 0.74; Stage II, k = 0.60; Stage III, k = 0.46; Stage IV, k = 0.59; Stage V, k = 0.27; and Stage VI, k = 0.78. An average of 10 of 21 (48%) of these errors involved Stage III. An average of 6.3 of 21 (30%) intraobserver errors involved Stage V. The presence of the crescent sign in Stage III and joint space narrowing in Stage V markedly diminished the overall reliability of any four- to six-stage classification system. Based on the authors' experience and analysis of the current classifications of osteonecrosis of the femoral head, an easy and reproducible Pittsburgh classification system is proposed.

Atraumatic osteonecrosis of the knee

BACKGROUND

The purposes of this study were to define the clinical, demographic, and radiographic patterns of atraumatic osteonecrosis of the distal part of the femur and the proximal part of the tibia at presentation and to report the outcome of treatment of this condition.

METHODS

Two hundred and forty-eight knees in 136 patients who were younger than the age of fifty-five years were treated at our institution between July 1, 1974, and September 15, 1998, for atraumatic osteonecrosis of the distal part of the femur or the proximal part of the tibia, or both. Demographic and radiographic features were characterized. The results of nonoperative treatment, core decompression, arthroscopic debridement, and total knee arthroplasty were evaluated.

RESULTS

There were 106 female patients and thirty male patients, and their mean age was thirty-six years (range, fifteen to fifty-four years) at the time of diagnosis. One hundred and one patients (74 percent) had involvement of other large joints, with eighteen (13 percent) presenting initially with knee symptoms. One hundred and one patients (74 percent) had a disease that affected the immune system; sixty-seven of them had systemic lupus erythematosus. One hundred and twenty-three patients (90 percent) had a history of corticosteroid use. Technetium-99m bone-scanning missed lesions in sixteen (29 percent) of fifty-six knees. Eight (20 percent) of forty-one initially symptomatic knees treated nonoperatively had a successful clinical outcome (a Knee Society score of at least 80 points and no additional surgery) at a mean of eight years. The knees that remained severely symptomatic for three months were treated with either core decompression (ninety-one knees) or total knee arthroplasty (seven knees). Seventy-two (79 percent) of the ninety-one knees treated with core decompression had a good or excellent clinical outcome at a mean of seven years. Efforts to avoid total knee arthroplasty with repeat core decompression or arthroscopic debridement led to a successful outcome in fifteen (60 percent) of twenty-five knees. Thirty-four (71 percent) of forty-eight knees treated with total knee arthroplasty had a successful clinical outcome at a mean of nine years.

CONCLUSIONS

Atraumatic osteonecrosis of the knee predominantly affects women, and in our study it was associated with corticosteroid use in 90 percent of the patients. Evaluation should include standard radiographic and magnetic resonance imaging of all symptomatic joints. Prognosis was negatively related to large juxta-articular lesions. Nonoperative treatment should be reserved for asymptomatic knees only. Core decompression was successful (a Knee Society score of at least 80 points and no additional surgery) in 79 percent of the knees in which the disease was in an early stage. Total knee arthroplasty was successful in only 71 percent of the knees.

Identifying structural hip and knee problems. Patient age, history, and limited examination may be all that's needed

A likely identification of a given structural disorder of the hip or knee can be suggested by the patient's age. In the hip, developmental dysplasia is usually found in infants, Legg-Calvé-Perthes disease in children of 4 to 10 years, slipped capital femoral epiphysis in somewhat older children, osteonecrosis in young to middle-aged adults, and degenerative joint disease and hip fracture in older adults. In the knee, Blount's disease is usually found in children aged 3 to 8, patellofemoral disease during the teens and early 20s, meniscal tears from the early teens through the mid-50s, ligament injuries from the teens to the 40s, and osteoarthritis throughout adulthood. With relatively little additional information, a useful diagnosis can be made so appropriate therapy can be started or referral made.

Osteonecrosis of the femoral head

New cases of osteonecrosis of the femoral head in the United States number between 10,000 and 20,000 per year. This disease usually affects patients in their late 30s and early 40s. Although a number of authors have related specific risk factors to this disease, its etiology, pathogenesis, and treatment remain a source of considerable controversy. This disorder has been associated with corticosteroid use, substance abuse, and various systemic medical conditions. Either direct damage to osteocytes (e.g., by toxin production) or indirect damage (e.g., due to disorders in fat metabolism or hypoxia) may lead to osteonecrosis. Patients at increased risk for osteonecrosis should be monitored closely. Unfortunately, most cases are diagnosed in an advanced stage of disease, when minimally invasive surgical procedures are no longer helpful. Furthermore, patients in the advanced stage of the disease must undergo total hip replacement at a young age, which carries a poor long-term prognosis.

Proximal femur fractures after free vascularized fibular grafting to the hip

The management of symptomatic femoral head osteonecrosis in young, active patients is troublesome and controversial. At the authors' institution, 707 consecutive free vascularized fibular grafts were performed for femoral head osteonecrosis between October 1979 and October 1995. Patients who underwent this procedure were at increased risk for proximal femur fractures because of the 16 to 21 mm core drilled through the lateral femoral cortex for removal of the avascular bone and placement of the fibular graft. An ongoing prospective database of patients who underwent this procedure was accessed to determine the incidence of and factors associated with postoperative subtrochanteric femur fractures. Eighteen subtrochanteric fractures occurred for an overall incidence of 2.5%. All fractures occurred through the core decompression site in the lateral femoral cortex. The treatment was nonoperative in seven patients and operative in 11. Fourteen of 18 fractures (77%) healed with an average of 4.1 months until radiographically documented union. Four fractures had nonunions develop, three of which later healed with bone grafting and internal fixation, whereas the fourth eventually required conversion to total hip arthroplasty. Twelve fractures in 251 patients occurred when the weightbearing regimen was touchdown weightbearing for the first 6 weeks and five fractures in 456 patients occurred when the weightbearing regimen was changed to nonweightbearing. The results indicate that nonweightbearing in the immediate postoperative period is associated with the lowest fracture rate.