Diagnostic Imaging and the Role of Stage and Lesion Size in Determining Outcome in Osteonecrosis of the Femoral Head:

Conservative Treatment in Avascular Necrosis of the Femoral Head: A Systematic Review

INTRODUCTION

Avascular necrosis (AVN) of the femoral head is a pressing orthopedic issue, leading to bone tissue death due to disrupted blood supply and affecting the quality of life of individuals significantly. This review focuses on conservative treatments, evaluating their efficacy as mainstay therapies. Enhanced understanding of AVN's pathophysiology and advancements in diagnostic tools have rekindled interest in non-surgical interventions, emphasizing personalized, multidisciplinary approaches for improved outcomes.

MATERIAL AND METHOD

A systematic search was conducted on PubMed, SCOPUS, and Google Scholar databases from January 2020 to August 2023, with the objective of focusing on conservative treatments for AVN of the femoral head. Eligible studies, including original research, case reports, and observational studies, were examined for relevant, well-documented patient outcomes post-conservative treatments, excluding non-English and surgically focused articles without comparative conservative data.

RESULTS

A systematic search yielded 376 records on AVN of the femoral head across multiple databases. After de-duplication and rigorous screening for relevance and quality, 11 full-text articles were ultimately included for a comprehensive qualitative synthesis, focusing on conservatively managing the condition.

CONCLUSIONS

This review evaluates the effectiveness of conservative treatments such as pharmacological interventions and physical modalities in managing AVN of the femoral head. Despite promising results in symptom alleviation and disease progression delay, variability in outcomes and methodological limitations in studies necessitate further rigorous, randomized controlled trials for a robust, patient-centric approach to optimize therapeutic outcomes in AVN management.

Modifications to advanced Core decompression for treatment of Avascular necrosis of the femoral head

BACKGROUND

"Advanced Core Decompression" (ACD) is a new technique for treatment of osteonecrosis of the femoral head (ONFH) that includes removal of the necrotic tissue using a percutaneous expandable reamer followed by refilling of the drill hole and the defect with an injectable, hard-setting, composite calcium sulphate (CaSO4)-calcium phosphate (CaPO4) bone graft substitute. As autologous bone has been shown to be superior to all other types of bone grafts, the aim of the study is to present and evaluate a modified technique of ACD with impaction of autologous bone derived from the femoral neck into the necrotic defect.

METHODS

A cohort of patients with an average follow-up of 30.06 months (minimum 12 months) was evaluated for potential collapse of the femoral head and any reasons that led to replacement of the operated hip. Only patients in stages 2a to 2c according to the Steinberg classification were included in the study.

RESULTS

In 75.9% the treatment was successful with no collapse of the femoral head or conversion to a total hip replacement. Analysis of the results of the different subgroups showed that the success rate was 100% for stage 2a lesions and 84.6% respectively 61.5% for stages 2b and 2c lesions.

CONCLUSIONS

Previous studies with a comparable follow-up reported less favourable results for ACD without autologous bone. Especially in stages 2b and 2c the additional use of autologous bone has a positive effect. In comparison to other hip-preserving techniques, the modified ACD technique is a very promising and minimally invasive method for treatment of ONFH.

TRIAL REGISTRATION

German clinical trials register ( DRKS00011269 , retrospectively registered).

Bilateral Avascular Necrosis of the Femoral Head in Fibrous Dysplasia

Fibrous dysplasia (FD) is an uncommon benign skeletal disorder, characterized by bone pain, deformities, and the development of pathological fractures. It is caused by osteoblastic lineage differentiation defects, leading to the replacement of normal bone with benign disorganized fibrous connective tissue. Avascular necrosis (AVN) of the femoral head is an insidious condition that can often be challenging to diagnose in its early stages. The pathogenesis of AVN is not well understood; however, it causes femoral head ischemia and collapse, often requiring hip arthroplasty. We report the first case of FD and bilateral AVN of the femoral head in the absence of an antecedent fracture. We postulate several mechanisms to explain how FD may result in AVN; however, further research is required to understand its pathophysiology and thus to guide clinical practice. © 2017 The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.

Core decompression and biotechnologies in the treatment of avascular necrosis of the femoral head

Avascular necrosis (AVN) of the femoral head (FH) causes 5% to 12% of total hip arthroplasties (THA). It especially affects active male adults between the third and fifth decades of life. The exact worldwide incidence is unknown. There are only few data related to each country, but most of it relates to the United States.Non-surgical management has a very limited role in the treatment of AVN of the FH and only in its earliest stages. Core decompression (CD) of the hip is the most common procedure used to treat the early stages of AVN of the FH. Recently, surgeons have considered combining CD with autologous bone-marrow cells, demineralised bone matrix or bone morphogenetic proteins or methods of angiogenic potential to enhance bone repair in the FH.Manuscripts were deemed eligible for our review if they evaluated treatment of early stage AVN of the FH with biotechnology implanted via CD. After application of eligibility criteria, we selected 19 reports for final analysis.The principal results showed that only by correctly mastering the therapeutic principles and adopting proper methods specifically oriented to different stages can the best therapeutic effect be achieved. Combining CD with biotechnology could result in a novel long-lasting hip- preserving treatment option.Furthermore, more refined clinical studies are needed to establish the effectiveness of biotechnology treatments in AVN of the FH. Cite this article: EFORT Open Rev 2017;2:41-50. DOI: 10.1302/2058-5241.2.150006.

Two-year follow-up after advanced core decompression

The so-called "Advanced Core Decompression" (ACD) is a new option that tries to remove the necrotic tissue in patients with osteonecrosis of the femoral head (AVN) in a minimally invasive way by the use of a percutaneous expandable reamer and refilling with a resorbable and osteoinductive bone-graft substitute. Seventy-two hips of sixty patients with a mean follow-up of 29.14 months after ACD have been included in this study. Patients underwent physical examination preoperatively and six weeks after surgery as well as at two further follow-ups. Certain phases in disease progression and size of the necrotic lesion were differentiated on the basis of the classification of osteonecrosis of the femoral head by Steinberg.The femoral heads had collapsed in 24 cases (33%). Analysis of the survival rates with regard to defect size revealed that the largest defects had a significantly higher rate of femoral head collapse than the smaller defects. Clinical scores were also depending on defect size but also on disease stage. The current ACD technique has not yet achieved any significant improvement in the success rate of core decompression procedures. It can be concluded that the success of ACD depends especially on the defect size. Copyright © 2015 John Wiley & Sons, Ltd.

How do radiologists evaluate osteonecrosis?

OBJECTIVES

Management of patients with osteonecrosis of the hip remains controversial and challenging. Because the prognosis and treatment are determined in large part by the stage and extent of the disease, it is important to use a reliable and efficient method for evaluation and staging. The objective of this study was to determine how musculoskeletal (MSK) radiologists evaluate osteonecrosis and whether this evaluation is adequate.

MATERIALS AND METHODS

A 12-part questionnaire was designed to determine how MSK radiologists evaluate patients with osteonecrosis of the femoral head (ONFH). This was sent to 888 members of the Society of Skeletal Radiology.

RESULTS

One hundred and twenty-one members responded to essentially all questions. Patients were evaluated using plain radiographs and MRI. All agreed that it is clinically important to determine the extent of necrosis and joint involvement, and 115 (95 %) stated that this should be part of the radiologists' evaluation. However, only 55 (46 %) said that in practice they used a specific system of classification, and most of these used the Ficat and Arlet classification, which does not indicate the extent of involvement. One hundred and seven (88 %) respondents included a simple visual estimate of the extent of involvement, and a small number added a specific measurement of lesion size. The majority indicated that they were infrequently consulted about which imaging studies should be obtained.

CONCLUSIONS

Although radiologists recognize the clinical importance of determining the extent of necrosis and joint involvement in patients with ONFH, in practice the methods used to evaluate these patients often do not accomplish this satisfactorily. The use of an effective classification, which includes both stage and extent of involvement, should be stressed, as it will lead to improved treatment of patients with ON. Physicians who order imaging studies for patients with ON should be encouraged to consult routinely with their radiology colleagues regarding which studies to request, as well as on the interpretation of these studies.

Osteonecrosis of the femoral head: An update in year 2012

Osteonecrosis is a phenomenon involving disruption to the vascular supply to the femoral head, resulting in articular surface collapse and eventual osteoarthritis. Although alcoholism, steroid use, and hip trauma remain the most common causes, several other etiologies for osteonecrosis have been identified. Basic science research utilizing animal models and stem cell applications continue to further elucidate the pathophysiology of osteonecrosis and promise novel treatment options in the future. Clinical studies evaluating modern joint-sparing procedures have demonstrated significant improvements in outcomes, but hip arthroplasty is still the most common procedure performed in these affected younger adults. Further advances in joint-preserving procedures are required and will be widely studied in the coming decade.

Advanced core decompression, a new treatment option of avascular necrosis of the femoral head--a first follow-up

Aseptic necrosis of the femoral head (AVN) leads to destruction of the affected hip joint, predominantly in younger patients. Advanced core decompression (ACD) is a new technique that may allow better removal of the necrotic tissue by using a new percutaneous expandable reamer. A further modification is the refilling of the drill hole and the defect with an injectable, hard-setting, composite calcium sulphate (CaSO₄)-calcium phosphate (CaPO₄) bone graft substitute. Compression tests were performed on seven pairs of femoral cadaver bones. One femur of each pair was treated with ACD, while the opposite side remained untreated. Clinically, the postoperative outcome of 27 hips in 23 patients was performed by physical examination 6 weeks after ACD and at average follow-up of 9.69 months, and compared with the preoperative results. MRI was used to assess the removal of the necrotic tissue, any possible progression of AVN and evaluation of collapse. In the biomechanical analysis, the applied maximum compression force that caused the fracture did not significantly differ from the untreated opposite side. The overall results of postoperative physical examinations were significantly better than preoperatively. Five hips (18.5%) were converted to a total hip replacement. The follow-up MRIs of the other patients showed no progression of the necrotic area. The first follow-up results of ACD have been encouraging for the early stages of aseptic necrosis of the femoral head. In our opinion, an assured advantage is the high stability of the femoral neck after ACD, which allows quick rehabilitation.

Bildgebung der aseptischen Femurkopfnekrose des Erwachsenen

The aim of diagnostic imaging procedures in avascular femoral head necrosis is to provide the patient with a stage-adapted therapy. Therefore, a differentiated diagnostic work-up is needed. Native radiography of the hip in two planes is still the first step. Over the past years, the diagnosis of femoral head necrosis has experienced tremendous improvement due to the use of MRI and CT scans. Because of these improvements the correct stage can be diagnosed early and the appropriate therapy can be initiated immediately. Today, MRI is the most sensitive diagnostic imaging procedure. CT scans can be particularly useful to exclude subchondral fractures. The use of bone scintigraphy is restricted to exceptional cases. In Europe, the ARCO classification of avascular femoral head necrosis has been widely accepted. It is essential here to define subtypes according to the localisation and the extent of the necrosis, because both have major influence on the prognosis of the disease and therefore also for the therapeutic strategy. In this overview, we describe the specific characteristics of the different diagnostic imaging procedures and illustrate them with appropriate imaging material. At the end of the article an algorithm for diagnostic imaging procedures in avascular femoral head necrosis for daily orthopaedic practice is proposed.