Core decompression combined with implantation of a demineralised bone matrix for non-traumatic osteonecrosis of the femoral head

Translational horizons in stem cell therapy for osteonecrosis of the femoral head: a journey from basic research to clinical practice through bibliometric insights

BACKGROUND

Osteonecrosis of the femoral head (ONFH) significantly impacts young and middle-aged adults, with steroid use implicated in many cases. Traditional treatments have limited efficacy, prompting a shift towards innovative approaches, such as stem cell therapy, offering less invasive regenerative solutions.

METHODS

Using bibliometric analysis from 1997 to 2023, we identified 392 articles on stem cell therapy for ONFH from the Web of Science Core Collection and analysed them using VOSviewer and CiteSpace to identify key trends and research directions.

RESULTS

From 1997 to 2023, stem cell therapy for ONFH research expanded significantly, with 392 articles evidencing global collaboration, particularly from China, the United States and South Korea. The field is characterised by 158 core authors across 26 clusters and contributions from 417 institutions in 104 research clusters, with Shanghai Jiao Tong University as a notable leader. This research is disseminated through 23 journal clusters, emphasising interdisciplinary work, with Clinical Orthopaedics and Related Research among the most influential journals. Key findings include the identification of the most influential papers, highlighting advances, such as use of autologous mesenchymal stem cells (MSCs) and innovative delivery mechanisms. High-frequency keyword analysis further mapped the evolution of the field, from basic mechanisms to advanced therapies, underscoring a trend towards more targeted stem cell treatments for ONFH.

CONCLUSION

Stem cell therapy for ONFH has advanced significantly, showcasing a successful transition from basic research to clinical practice, particularly highlighted by developments in use of autologous MSCs and delivery methods. Future research will focus on refining therapies through exosome technology, targeted modulation of stress and inflammation and integration with surgical techniques, with the aim of tailored patient care and improved ONFH outcomes.

Bone tissue engineering for treating osteonecrosis of the femoral head

Osteonecrosis of the femoral head (ONFH) is a devastating and complicated disease with an unclear etiology. Femoral head-preserving surgeries have been devoted to delaying and hindering the collapse of the femoral head since their introduction in the last century. However, the isolated femoral head-preserving surgeries cannot prevent the natural progression of ONFH, and the combination of autogenous or allogeneic bone grafting often leads to many undesired complications. To tackle this dilemma, bone tissue engineering has been widely developed to compensate for the deficiencies of these surgeries. During the last decades, great progress has been made in ingenious bone tissue engineering for ONFH treatment. Herein, we comprehensively summarize the state-of-the-art progress made in bone tissue engineering for ONFH treatment. The definition, classification, etiology, diagnosis, and current treatments of ONFH are first described. Then, the recent progress in the development of various bone-repairing biomaterials, including bioceramics, natural polymers, synthetic polymers, and metals, for treating ONFH is presented. Thereafter, regenerative therapies for ONFH treatment are also discussed. Finally, we give some personal insights on the current challenges of these therapeutic strategies in the clinic and the future development of bone tissue engineering for ONFH treatment.

Optimal drilling at femoral head-neck junction for treatment of the femoral head necrosis: Experimental and numerical evaluation

BACKGROUND

Advanced core decompression (ACD) is a relative new technique for treatment of early stages of avascular femoral head necrosis. Although it is a promising treatment option, there is a need to modify this technique for achieving higher hip survival rates. An idea was to combine this technique with the lightbulb procedure in order to get a complete removal of the necrosis. This study aimed at evaluating the fracture risk of the femora treated by the combined Lightbulb-ACD technique as the basis for clinical application.

METHODS

Subject-specific models were generated from CT scan data of five intact femora. Several treated models were then created from each intact bone and simulated during normal walking activity. Biomechanical testing was additionally performed on 12 pairs of cadaver femora to confirm the simulation results.

FINDINGS

The finite element results revealed that the risk factor of the treated models with a 8 mm-drill increased, but was not significantly greater than that of their corresponding intact models. However, for the femur treated with a 10 mm-drill, the risk factor increased significantly. Fracture always initiated on the femoral neck, i.e. it was either subcapital or transcervical fracture. Our biomechanical testing results correlated well with the simulation data which confirmed the usefulness and effectiveness of the bone models.

INTERPRETATION

The combined Lightbulb-ACD technique using a 10 mm drill increased the fracture risk of femur postoperatively. A drill of up to 8 mm at the anterior head-neck junction did not however lead to the weakening of the femur so that full load bearing may be possible.

A rat model of ischemic osteonecrosis for investigating local therapeutics using biomaterials

Osteonecrosis is one of the most disabling diseases affecting pediatric and adult populations. Local application of biomaterials is a promising therapeutic strategy for osteonecrosis. Currently, there is a lack of low-cost animal models of osteonecrosis for testing and developing biomaterials-driven therapeutics. To develop a rat model of ischemic osteonecrosis (IO), the distal femoral epiphysis was selected due to its size 7.7 folds larger than the proximal femoral epiphysis (p<0.0001). The feasibility of intraosseous drillings and the local application of biomaterials were determined. Four model biomaterials were successfully applied: injectable hydrogel, microsphere, bone cement, and implant. The IO was induced by surgically cauterizing the blood vessels supplying the distal femoral epiphysis. Osteonecrosis of the whole epiphysis was achieved with a complete absence of blood flow and near 100% of apoptotic osteocytes. At eight weeks after IO, severe bone deformity and osteoarthritis developed in the affected epiphysis. The histological analysis showed 50% lacunae empty in the IO group compared to 2% in the control group (p<0.0001). The μCT analysis showed the epiphyseal quotient decreased to 0.46 in the IO group compared to 0.53 in the control group (p<0.0001), and the distal femoral epiphysis in the IO group was 19% smaller than the control group (p<0.01). The Safranin O stained sections showed articular cartilage erosions and subchondral bone fractures in the IO group. In summary, we established a clinically relevant IO model on rats that is compatible with the application of biomaterials for treatment. STATEMENT OF SIGNIFICANCE: Osteonecrosis is one of the most serious orthopedic conditions, leading to permanent joint deformity and end-stage osteoarthritis. An efficient and low-cost animal model is essential for development and testing of new treatment strategies for osteonecrosis. This is the first study to develop a clinically relevant model of osteonecrosis on the distal femoral epiphysis of rats. The model is highly efficient in developing osteonecrosis with relatively low cost and it provides suitable skeletal size to apply various forms of biomaterials. More importantly, it mimicked the pathological features and progression of osteonecrosis in humans. The study is expected to have an important impact on the development and testing of innovative biological therapeutics for osteonecrosis.

Serum Insufficiency Induces RANKL-Independent Osteoclast Formation during Developing Ischemic ONFH

Blood supply interruption induces hypoxia and reduces serum provision to cause ischemia-induced osteonecrosis, including avascular osteonecrosis of the femoral head (ONFH). Oxygen deficiency (hypoxia) is known to induce different expression patterns in osteoblasts and osteoclasts, which have been extensively studied. However, the effects of serum insufficiency in nutrients, growth factors, and hormones on osteoblast and osteoclast activity in the damaged area and nearby regions remain poorly understood. In this study, the expression of osteoblast and osteoclast marker proteins was elucidated through in vitro and ex vivo studies. The results indicate that serum insufficiency accelerates the formation of monocyte-derived osteoclasts. The combined effect of serum insufficiency and hypoxia (mimicking ischemia) suppressed the activity of alkaline phosphatase and calcification in osteoblasts after the stimulation of osteogenic growth factors. Serum insufficiency increased the activity of tartrate-resistant acid phosphatase, expression of phosphorylated extracellular signal-regulated kinases, and production of reactive oxygen species in monocyte-derived osteoclasts in the absence of receptor activator of nuclear factor kappa-Β ligand stimulation. The findings indicate that changes in the expression of osteoblast and osteoclast markers in necrotic bone extracts were similar to those observed during an in vitro study. These results also suggest that serum insufficiency may be involved in the regulation of osteoclast formation in patients with ONFH.

Multiple drilling is not effective in reducing the rate of conversion to Total hip Arthroplasty in early-stage nontraumatic osteonecrosis of the femoral head: a case-control comparative study with a natural course

BACKGROUND

To determine whether multiple drilling is effective in postponing the need for total hip arthroplasty (THA) in early-stage nontraumatic osteonecrosis of the femoral head (ONFH).

METHODS

We identified 514 patients who were diagnosed with early-stage ONFH between January 2008 and December 2018. One hundred ninety-six patients underwent multiple drilling, and 318 patients had a natural course of progression. One hundred fifty-nine patients were selected for each group after case-control matching for preoperative demographics and modified Ficat and Arlet stage. The rates of THA conversion were compared. We also performed Cox regression to identify risk factors associated with THA conversion in patients who underwent multiple drilling.

RESULTS

Kaplan-Meier survivorship with an endpoint of THA for nontraumatic reasons were not significantly different between the multiple drilling group (75.6, 95% confidence interval 67.8-83.4%) and the natural course group (72.2, 95% confidence interval 64.8-79.6%) at 5 years (log-rank, P = .191). In the Cox regression model, a larger extent of necrotic lesion, bone marrow edema (BME), and higher postoperative work intensity significantly increased the risk of THA conversion (P < .05). Among patients treated with autogenous bone grafting, there was a lower risk of failure in patients with necrotic lesion less than 15% (P < .05).

CONCLUSIONS

Multiple drilling is not effective in reducing the rate of THA conversion in early-stage nontraumatic ONFH. The risk of conversion to THA after multiple drilling is increased by a larger extent of necrotic lesion, presence of BME, and higher postoperative work intensity in patients with early-stage ONFH.

TRIAL REGISTRATION

The trial was registered in the Chinese Clinical Trial Registry ( ChiCTR2000035180 ) dated 2 August 2020.

Core Decompression and Biological Treatment in Osteonecrosis of the Hip due to Systemic Lupus Erythematosus, 8-year Follow-up: A Case Report

BACKGROUND: Osteonecrosis most commonly affects the femoral head, especially in middle-aged adults. It can be caused by trauma, chronic inflammation, or infection. It leads to collapse of the entire femoral head and culminates with total hip replacement. CASE REPORT: A 29-year-old female with systemic lupus erythematosus (SLE) had a chief complaint of bilateral hip pain. She was diagnosed with early osteonecrosis of the femoral head (FICAT stage II) using magnetic resonance imaging and core decompression surgery was performed using three small diameter (4 mm) drillings and added biological treatment. She was evaluated with a visual analog scale (VAS), Harris hip score (HHS), and plain radiography in the pre-operative stage and post-operative follow-up. RESULTS: Functional outcome at 8-year follow-up showed improvement with significantly decreased VAS (pre-operative: 5, post-operative: 0), significant improvement of HHS from 52.725 points (poor) pre-operative to 92.025 points (excellent) post-operative, and subsided femoral head lesion. CONCLUSIONS: Surgical decompression and biological treatment result in decreased intraosseous pressure and enhanced osteogenesis. It can restrict the SLE disease progression and limit the number of cell death.

Treatment of aseptic osteonecrosis of the femoral head: Historical aspects

The treatment of aseptic osteonecrosis (ON) of the femoral head has been the subject of numerous therapeutic and surgical proposals due to the absence of medical treatment with proven efficacy. For many years, the goal of surgical treatment was to avoid total hip replacement (THR) with uncertain survival in patients considered too young (30-50 years) for this procedure. Numerous conservative treatments were thus proposed: core decompression with numerous variants, non-vascularized and vascularized bone grafts, intertrochanteric and rotational transtrochanteric osteotomies, cementing. The lack of a common classification and a lack of knowledge of natural history complicated the interpretation of the results for a long time. Nevertheless, it appeared that these treatments were effective only in the very early stages and among these in the limited ONs, medial rather than central and especially lateral, with discrepancies according to etiologies apart from sickle cell disease recognized by all as being pejorative. For the same reason, partial arthroplasties have been attempted and abandoned in turn: femoral head total and partial resurfacing and femoral prosthesis. The most recent advances are stem-cell-enhanced core decompression and progress in total arthroplasty, whose reliability has made it possible to extend the indications to increasingly younger patients seeking treatment with guaranteed or near-guaranteed efficacy. Most of the other interventions have disappeared or almost disappeared because of their lack of effectiveness especially in extensive and post-fracture ONs, sometimes because of their complexity and the length of their post-operative management, and also because they complicate and penalize a future total arthroplasty. This argues for early detection of ON at an early stage where the "head can be saved" by stem cell augmented core decompression, a minimally invasive treatment that leaves the chances of success of a THR intact.

Implantation of autologous Expanded Mesenchymal Stromal Cells in Hip Osteonecrosis through Percutaneous Forage: Evaluation of the Operative Technique

Bone forage to treat early osteonecrosis of the femoral head (ONFH) has evolved as the channel to percutaneously deliver cell therapy into the femoral head. However, its efficacy is variable and the drivers towards higher efficacy are currently unknown. The aim of this study was to evaluate the forage technique and correlate it with the efficacy to heal ONFH in a multicentric, multinational clinical trial to implant autologous mesenchymal stromal cells expanded from bone marrow (BM-hMSCs). Methods: In the context of EudraCT 2012-002010-39, patients with small and medium-sized (mean volume = 13.3%, range: 5.4 to 32.2) ONFH stage II (Ficat, ARCO, Steinberg) C1 and C2 (Japanese Investigation Committee (JIC)) were treated with percutaneous forage and implantation of 140 million BM-hMSCs in a standardized manner. Postoperative hip radiographs (AP—anteroposterior and lateral), and MRI sections (coronal and transverse) were retrospectively evaluated in 22 patients to assess the femoral head drilling orientation in both planes, and its relation to the necrotic area. Results: Treatment efficacy was similar in C1 and C2 (coronal plane) and in anterior to posterior (transverse plane) osteonecrotic lesions. The drill crossed the sclerotic rim in all cases. The forage was placed slightly valgus, at 139.3 ± 8.4 grades (range, 125.5–159.3) with higher dispersion (f = 2.6; p = 0.034) than the anatomical cervicodiaphyseal angle. Bonferroni’s correlation between both angles was 0.50 (p = 0.028). More failures were seen with a varus drill positioning, aiming at the central area of the femoral head, outside the weight-bearing area (WBA) (p = 0.049). In the transverse plane, the anterior positioning of the drill did not result in better outcomes (p = 0.477). Conclusion: The forage drilling to deliver cells should be positioned within the WBA in the coronal plane, avoiding varus positioning, and central to anterior in the transverse plane. The efficacy of delivered MSCs to regenerate bone in ONFH could be influenced by the drilling direction. Standardization of this surgical technique is desirable.

Quantitative Characterization of Bone Viability of Femoral Head and Subchondral Bone by Using Single Photon Emission Computerized Tomography/Computerized Tomography (SPECT/CT)

Background

Vascularized fibular grafting (VFG) has been successfully employed for treating avascular necrosis of the femoral head (ANFH). In this study, we aimed to evaluate the bone viability of the femoral head and subchondral bone following VFG by using single photon emission computerized tomography and computerized tomography (SPECT/CT).

Material/Methods

Between March 2011 and June 2014, 14 ANFH patients (17 hips) treated with VFG at Zhongshan Hospital, Fudan University, were prospectively enrolled. The patients included 9 males and 5 females with an average age of 26.6 years (range, 18–34 years). According to the ARCO (Association Research Circulation Osseous) stage criteria, 3 hips corresponded to stage IIA, 4 hips to stage IIB, 2 hips to stage IIC, 5 hips to stage IIIA, and 3 hips to stage IIIB. A novel method based on SPECT/CT was developed to quantitative characterized the bone viability of femoral head and subchondral bone prior to surgery and at 3 months after VFG. All patients were followed for an average duration of 3.8 years (ranging 2.6–5.5 years).

Results

The bone viability of the femoral head (V_fh) and subchondral bone (V_sb) of patients’ hips at ARCO stage III was 58.9±7.6 and 48.9±6.1, respectively, which were significantly lower than the preoperative V_fh (78.1±5.2) and V_sb (69.8±4.3) of hips at stage II (P<0.05). The V_fh of hips at stage II improved to 104.0±9.7 at 3 months post-intervention, and there was no significant difference compared with the V_fh (97.3±7.4) of hips at stage III (P=0.15). The V_sb of hips at stage III improved to 80.4±7.3 at 3 months after VFG; however, this value was significantly lower than that of hips at stage II (92.7±5.5) (P<0.05).

Conclusions

The V_fh and V_sb of our patients were associated with their ARCO stages, and could be improved after vascularized fibular grafting procedure as measured by SPECT/CT.

Guidelines for clinical diagnosis and treatment of osteonecrosis of the femoral head in adults (2019 version)

Osteonecrosis of the femoral head (ONFH) is a common and refractory disease in orthopaedic clinics. The number of patients with ONFH is increasing worldwide every year. There are an estimated 8.12 million patients with nontraumatic osteonecrosis in China alone. Treatment of nontraumatic osteonecrosis has always been a clinical challenge for orthopaedic surgeons. To further standardize diagnosis and treatment of ONFH, these guidelines provide not only basic diagnosis, treatment, and evaluation systems for ONFH but also expert advice and standards in many aspects, including epidemiology, aetiology, diagnostic criteria, pathological staging, prevention and treatment options, and postoperative rehabilitation. The aetiological factors of ONFH can currently be divided into two major categories: traumatic and nontraumatic; however, the specific pathological mechanism of ONFH is not completely clear. Currently, the staging system of ONFH formulated by the Association Research Circulation Osseous is widely used in clinical practice. Based on the changes in the intraosseous blood supply at different stages, the corresponding nonsurgical and surgical treatments are recommended, and when there are risk factors for possible ONFH, certain preventive measures to avoid the occurrence of osteonecrosis are recommended. These guidelines provide brief classification criteria and treatment regimen for osteonecrosis. Specification of the aetiology, treatment plan based on comprehensive consideration of the different stages of osteonecrosis, hip function, age, and occupation of the patients are important steps in diagnosis and developing treatment strategies.

TRANSLATIONAL POTENTIAL OF THIS ARTICLE

New advances in the epidemiology, etiology, pathophysiology, imaging, diagnosis and treatment of ONFH have been renewed in this revision. This guideline can be used for reference by orthopedic professionals and researchers, and for standardized diagnosis and treatment management under the clinical guidance, which is conducive to the prevention, treatment and further research of ONFH, improving the diagnosis and treatment level, making patients' symptoms under good control, and improving their quality of life.

Comparison of sartorius muscle-pedicle and circumflex iliac deep bone flap grafts in the treatment of early non-traumatic osteonecrosis of femoral head in young adults

Objective

The aim of this study was to retrospectively compare and evaluate the midterm curative effect of two different bone flap grafts in the treatment of early non-traumatic osteonecrosis of the femoral head (ONFH).

Methods

A total of 180 patients (199 hips) with early non-traumatic ONFH received surgical treatment by sartorius muscle-pedicle bone flap graft (SMBF) (104 patients, 64 males and 40 females; mean age 34.67 ± 3.24 years) or circumflex iliac deep bone flap graft (CIDBF) (76 patients, 44 males and 32 females; mean age: 35.54 ± 3.37 years) from July 2004 to July 2009. The comparison between the groups was made with Harris score before and after surgery, length of incision, operative time, amount of bleeding, postoperative X-ray. Association Research Circulation Osseous (ARCO) staging was performed.

Results

The preoperative Harris hip score of two groups were 68.26 ± 1.26 and 69.35 ± 1.31, respectively. Patients' ARCO staging indicated 36 hips of stage IIa, 115 hips of stage IIb and 48 hips of stage IIc. The etiology of ONFH mainly including hormones (93 patients), alcohol (64 patients) and other (23 patients). The mean follow-up time of SMBF and CIDBF groups were (51.78 ± 2.35) and (52.73 ± 3.71) months, respectively. The time of removing sutures, operation time, amount of bleeding and length of incision in SMBF group were superior to those in the CIDBF group, and those differences between the SMBF and CIDBF groups were not significant (all p values > 0.28). The Harris score between the two groups was similar after operation and postoperative 12 month, and the difference was not statistically significant (p > 0.05), whereas the difference of the postoperative 24 and 48 months was statistically significant (p ˂ 0.05). X-ray analysis showed improvement of osteonecrosis in both two groups after surgery, and as time went on, the total hip amount decreased, the replacement amount increased.

Conclusion

Both bone flap grafts appear to be effective methods for treatment of early osteonecrosis of femoral head (ARCOⅡ), and the SMBF is a relatively simple technique and easy for mastering, and it is a reliable method for clinical application.

Level of evidence

Level III, Therapeutic Study.

Regenerative Medicine Applications of Mesenchymal Stem Cells

A major research challenge is to develop therapeutics that assist with healing damaged tissues and organs because the human body has limited ability to restore the majority of these tissues and organs to their original state. Tissue engineering (TE) and regenerative medicine (RM) promises to offer efficient therapeutic biological strategies that use mesenchymal stem cells (MSCs). MSCs possess the capability for self-renewal, multilineage differentiation, and immunomodulatory properties that make them attractive for clinical applications. They have been extensively investigated in numerous preclinical and clinical settings in an attempt to overcome their challenges and promote tissue regeneration and repair. This review explores the exciting opportunities afforded by MSCs, their desirable properties as cellular therapeutics in RM, and implicates their potential use in clinical practice. Here, we attempt to identify challenges and issues that determine the clinical efficacy of MSCs as treatment for skeletal and non-skeletal tissues.

Chinese Guideline for the Diagnosis and Treatment of Osteonecrosis of the Femoral Head in Adults

The treatment of adult osteonecrosis of the femoral head (ONFH), with 8.12 million patients in China, remains a challenge to surgeons. To standardize and improve the efficacy of the treatment of ONFH, Chinese specialists updated the experts' suggestions in March 2015, and an experts' consensus was given to provide a current basis for the diagnosis, treatment and evaluation of ONFH. The current guideline provides recommendations for ONFH with respect to epidemiology, etiology, diagnostic criteria, differential diagnosis, staging, treatment, as well as rehabilitation. Risk factors of non-traumatic ONFH include corticosteroid use, alcohol abuse, dysbarism, sickle cell disease and autoimmune disease and others, but the etiology remains unclear. The Association Research Circulation Osseous (ARCO) staging system, including plain radiograph, magnetic resonance imaging, radionuclide examination, and histological findings, is frequently used in staging ONFH. A staging and classification system was proposed by Chinese scholars in recent years. The major differential diagnoses include mid-late term osteoarthritis, transient osteoporosis, and subchondral insufficiency fracture. Management alternatives for ONFH consist of non-operative treatment and operative treatment. Core decompression is currently the most common procedure used in the early stages of ONFH. Vascularized bone grafting is the recommended treatment for ARCO early stage III ONFH. This guideline gives a brief account of principles for selection of treatment for ONFH, and stage, classification, volume of necrosis, joint function, age of the patient, patient occupation, and other factors should be taken into consideration.

An evidence-based guide to the treatment of osteonecrosis of the femoral head

Non-traumatic osteonecrosis of the femoral head is a potentially devastating condition, the prevalence of which is increasing. Many joint-preserving forms of treatment, both medical and surgical, have been developed in an attempt to slow or reverse its progression, as it usually affects young patients. However, it is important to evaluate the best evidence that is available for the many forms of treatment considering the variation in the demographics of the patients, the methodology and the outcomes in the studies that have been published, so that it can be used effectively. The purpose of this review, therefore, was to provide an up-to-date, evidence-based guide to the management, both non-operative and operative, of non-traumatic osteonecrosis of the femoral head. Cite this article: Bone Joint J 2017;99-B:1267-79.

Efficacy of core decompression for treatment of canine femoral head osteonecrosis induced by arterial ischaemia and venous congestion

METHODS

40 healthy mixed-breed dogs were randomly divided into 2 groups, arterial ischaemia (AI) and venous congestion (VC), each containing 20 dogs. The dogs underwent a procedure where the deep femoral artery or deep femoral vein was ligated randomly on the left or right side to establish the femoral head osteonecrosis model. 13 dogs from each group, AI and VC, were randomly selected for subsequent study. 3 dogs were randomly chosen from each group to receive core decompression (CD) every 2 weeks for a total of 4 sessions.

RESULTS

The development of femoral head osteonecrosis was slightly slowed at each measurement time point after CD in the arterial ischaemia (AI) group, but no restoration was observed. The venous congestion (VC) group showed a gradually reduced mixed signal after CD and exhibited a trend towards restoration. The various VC subgroups had significantly improved symptoms compared to the AI subgroups.

CONCLUSIONS

CD displayed greater treatment efficacy for femoral head osteonecrosis caused by VC, but poor efficacy for femoral head osteonecrosis caused by AI.

Long-term results of rotational acetabular osteotomy for osteonecrosis with collapse of the femoral head in young patients

PURPOSE

The surgical treatment of osteonecrosis with collapse of the femoral head is still controversial. The purpose of this study was to investigate the clinical outcome of rotational acetabular osteotomy by Ninomiya and Tagawa for osteonecrosis of the femoral head in young patients.

PATIENTS AND METHODS

Rotational acetabular osteotomy was performed in 202 consecutive patients between 1995 and 2003. Among them, rotational acetabular osteotomy with osteonecrosis of the femoral head was performed in 31 patients (42 hips). The mean age at the time of surgery was 31.2 years (range 16-45). The mean duration of follow-up was 16.1 years (range 13.1-21 years).

RESULTS

The mean preoperative Japanese Orthopedic Association hip score of 56.8 points improved to a mean of 72.4 points at the final follow-up. The 10-year survival rate with conversion to total hip arthroplasty as an end-point was 91.9%, and the 15-year survival rate was 75.5%, the 20-year survival rate was 67.9%. The conversion to total hip arthroplasty was performed in nine hips. The average time to the conversion to total hip arthroplasty was 12.1 years.

CONCLUSIONS

Even though the necrotized range is wide, if normal cartilage remains on the lateral side of the femoral head, it can be utilized for the weight-bearing region by laterally rotating the acetabulum. Since the outcome was favorable, we believe that this is a valuable treatment option for this disease.

Inverted femoral head graft versus standard core decompression in nontraumatic hip osteonecrosis at minimum 3 years follow-up

PURPOSE

Numerous salvage surgeries were popularised to halt the progression of hip osteonecrosis (ON). We aimed to compare the clinico-radiological outcomes of inverted femoral head graft (IFHG) versus standard core decompression (SCD) in treatment of nontraumatic hip ON at pre-arthritic stage.

METHODS

A case review was performed at a minimum 3 years follow-up of 61 patients (71 hips; mean age 32.96 (19-50) years; mean follow-up 7.86 (3-14) years; mean body mass index 28.58 (19-46); 32 males, 29 females) suffering nontraumatic hip ON at pre-arthritic stage. 38 hips underwent SCD and 33 IFHG. The outcome was assessed by changes in modified Harris Hip Score (MHHS), need for revision surgery and progression of modified Ficat-Arlet staging. Data were analysed including logistic regression and Kaplan-Meier survivorship analysis.

RESULTS

13/34 (38.2%) hips in SCD group were revised at 4.61 ± 2.61 years, while 7/33 (21.2%) in IFHG group at 8.43 ± 4.32 years (p = 0.023). MHHS was significantly higher in IFHG group at 1 and 3 years as well as at last follow-up (p = 0.014, 0.001 and 0.023 respectively). Clinical and radiological significant differences were found in survivorship analysis between both groups, in favor of IFHG. A higher clinical failure was noted among obese patients.

CONCLUSIONS

An IFHG technique offers a better alternative regarding postoperative clinico-radiological outcomes in nontraumatic hip ON at the pre-arthritic stage. A cautious prognosis is recommended in obese patients.

Effect of the stiffness of bone substitutes on the biomechanical behaviour of femur for core decompression

Core decompression is the most common procedure for treatment of the early stages of osteonecrosis of the femoral head. The purpose of this study was to compare the biomechanical performance of four different bone graft substitutes combined with core decompression. Subject-specific finite element models generated from computed tomography (CT) scan data were used for a comprehensive analysis. Two different contact conditions were simulated representing states of osseointegration at the interface. Our results showed that the use of a low-stiffness bone substitute did not increase the risk of femoral fracture in the early postoperative phase, but resulted in less micromotion and interfacial stresses than high-stiffness bone substitutes.

Mechanism of chlorogenic acid treatment on femoral head necrosis and its protection of osteoblasts

The aim of the present study was to investigate the therapeutic effect of chlorogenic acid on hormonal femoral head necrosis and its protection of osteoblasts. The study established a femoral head necrosis model in Wistar rats using Escherichia coli endotoxin and prednisolone acetate. The rats were divided into five groups and were treated with different concentrations of chlorogenic acid (1, 10 and 20 mg/kg). The main detected indicators were the blood rheology, bone mineral density, and the hydroxyproline and hexosamine (HOM) contents. At a cellular level, osteoblasts were cultured and treated by drug-containing serum. Subsequently, cell proliferation and the osteoblast cycle were measured using flow cytometry, and the protein expression levels of Bax and B-cell lymphoma 2 (Bcl-2) were detected using western blotting. Chlorogenic acid at a concentration of 20 mg/kg (high-dose) enhanced the bone mineral density of the femoral head and femoral neck following ischemia. Simultaneously, blood flow following the injection of prednisolone acetate was significantly improved, and the HOM contents of the high-dose chlorogenic acid group were significantly different. The results from the flow cytometry analysis indicated that chlorogenic acid can efficiently ameliorate hormone-induced necrosis. The osteoblasts were isolated and cultured. The MTT colorimetric assay showed that chlorogenic acid at different densities can increase the proliferation capabilities of osteoblasts and accelerate the transition process of G₀/G₁ phase to S phase, as well as enhance mitosis and the regeneration of osteoblasts. Western blotting detection indicated that chlorogenic acid may prohibit the decrease of Bcl-2 and the increase of Bax during apoptosis, thereby inhibiting osteoblast apoptosis and preventing the deterioration of femoral head necrosis. In conclusion, chlorogenic acid at the density of 20 mg/kg is effective in the treatment of hormonal femoral head necrosis, which may be applicable for future treatment.

Core decompression or quadratus femoris muscle pedicle bone grafting for nontraumatic osteonecrosis of the femoral head: A randomized control study

BACKGROUND

The traditional management for osteonecrosis of the femoral head (ONFH) includes core decompression (CD) and quadratus femoris muscle pedicle bone graft (QF-MPBG). The aim of this study was to investigate the effects of CD and QF-MPBG on the patients with nontraumatic ONFH in an early stage.

MATERIALS AND METHODS

39 patients (47 hips) with ONFH in an early stage (Ficat Stage I or II) were randomly divided into two groups according to random number table method. One group was treated with CD and cancellous bone grafting. Another group was treated QF-MPBG with cancellous bone grafting. The hip function was evaluated using Harris hip score (HHS). The repair of the femoral head was estimated through X-ray, computed tomography (CT), or magnetic resonance imaging (MRI). The surgical time and intraoperative blood loss was calculated.

RESULTS

All patients were followed for an average 2.5 years (range from 1.5 to 4 years). Two hips in CD group progressed into stage 3 and three hips in QF-MPBG group processed into stage 3. No patient accepted the THA at the last followup. The HHSs significantly increased in both groups after surgery (P < 0.05). No statistical differences were found between CD and QF-MPBG groups in postoperative HHSs at last followup (P > 0.05). X-ray and CT showed that the femoral head did not progress to collapse after operation in both groups. In addition, MRI showed that the edema signals decreased. However, the surgical time was longer in QF-MPBG group than that in CD group (P < 0.05). The intraoperative blood loss was more in QF-MPBG than that in CD group (P < 0.05).

CONCLUSION

The CD with bone graft could relieve hip pain, improve hip function with much lesser surgical trauma compared to QF-MPBG. Hence, the CD with bone graft should be generally used for the treatment of patients with an early stage (Ficat Stage I or II) ONFH.

The Fate and Distribution of Autologous Bone Marrow Mesenchymal Stem Cells with Intra-Arterial Infusion in Osteonecrosis of the Femoral Head in Dogs

This study aimed to investigate if autologous bone marrow mesenchymal stem cells (MSCs) could treat osteonecrosis of the femoral head (ONFH) and what the fate and distribution of the cells are in dogs. Twelve Beagle dogs were randomly divided into two groups: MSCs group and SHAM operated group. After three weeks, dogs in MSCs group and SHAM operated group were intra-arterially injected with autologous MSCs and 0.9% normal saline, respectively. Eight weeks after treatment, the necrotic volume of the femoral heads was significantly reduced in MSCs group. Moreover, the trabecular bone volume was increased and the empty lacunae rate was decreased in MSCs group. In addition, the BrdU-positive MSCs were unevenly distributed in femoral heads and various vital organs. But no obvious abnormalities were observed. Furthermore, most of BrdU-positive MSCs in necrotic region expressed osteocalcin in MSCs group and a few expressed peroxisome proliferator-activated receptor-γ (PPAR-γ). Taken together, these data indicated that intra-arterially infused MSCs could migrate into the necrotic field of femoral heads and differentiate into osteoblasts, thus improving the necrosis of femoral heads. It suggests that intra-arterial infusion of autologous MSCs might be a feasible and relatively safe method for the treatment of femoral head necrosis.

The formation and function of the sclerosis rim in the femoral head: A biomechanical point of view

Sclerosis rim surrounding the necrotic area is commonly found in necrotic femoral head, but the biomechanical function of sclerosis rim has received relatively little attention. Little is known about the formation and natural history of sclerosis rim. In the present work, we assume that the necrotic change may trigger bone remodeling process in the femoral head, which took place according to Huiskes' bone remodeling model incorporated with the FE simulations as described earlier. We then investigate the function of sclerosis rim as a mechanical supporter in delaying further collapse of the femoral head based on our sclerotic rim model. The main tasks of this study are: (1) simulation of the density distribution in the necrotic femoral head after bone remodeling; (2) calculation of maximal von Mises stress in the subchondral bone of the weight-bearing area of the femoral head over the necrotic area before and after bone remodeling. Results show that the sclerotic rim is, from the biomechanical point of view, an adaptive response to the decrease in elastic modulus of the femoral head, and that the sclerotic rim that acts as a compensatory structural reinforcement can usually significantly reduce the maximal stress in the subchondral bone when the lesion is small, but not when the lesion is large.

Nontraumatic Osteonecrosis of the Femoral Head: Where Do We Stand Today? A Ten-Year Update

➤ Although multiple theories have been proposed, no one pathophysiologic mechanism has been identified as the etiology for the development of osteonecrosis of the femoral head. However, the basic mechanism involves impaired circulation to a specific area that ultimately becomes necrotic.➤ A variety of nonoperative treatment regimens have been evaluated for the treatment of precollapse disease, with varying success. Prospective, multicenter, randomized trials are needed to evaluate the efficacy of these regimens in altering the natural history of the disease.➤ Joint-preserving procedures are indicated in the treatment of precollapse disease, with several studies showing successful outcomes at mid-term and long-term follow-up.➤ Studies of total joint arthroplasty, once femoral head collapse is present, have described excellent outcomes at greater than ten years of follow-up, which is a major advance and has led to a paradigm shift in treating these patients.➤ The results of hemiresurfacing and total resurfacing arthroplasty have been suboptimal, and these procedures have restricted indications in patients with osteonecrosis of the femoral head.

Sartorius muscle-pedicle bone graft for osteonecrosis of the femoral head

PURPOSE

This study summarises the clinical efficacy of sartorius muscle-pedicle bone graft in osteonecrosis of the femoral head.

METHODS

A total of 58 patients, including 53 men (61 hips) and five women (6 hips) with osteonecrosis of the femoral head, underwent sartorius muscle-pedicle bone grafting. Association Research Circulation Osseous (ARCO) staging was performed.

RESULTS

The ARCO staging revealed 23 hips of stage I, 36 hips of stage II and eight hips of stage III. The average surgical duration was 65 minutes (range 45-90 minutes). A total of 55 (64 hips) of the 58 patients undergoing surgery were followed up, with a mean follow-up duration of 34.48 months (range, 24-48 months) and a median of 34 months. The outcome was excellent in 27, good in 24, normal in two, and poor in 11 hips, with a total good rating of 79.68 %. The Harris score of the hip joints in the last follow-up was significantly improved compared with pre-surgical scores (P < 0.01). Imaging results showed that 21 hips were improved, 31 hips were stabilized and 12 hips were aggravated (of which 9 hips underwent total hip replacement). The survival rate of femoral head was 81.25 %.

CONCLUSION

Sartorius muscle-pedicle bone graft significantly promotes repair of osteonecrosis of the femoral head, improves the Harris score of the hip joints, with good clinical efficacy. It effectively improves the survival rate of femoral head, delaying or preventing artificial hip replacement.

Management of femoral head osteonecrosis: Current concepts

Osteonecrosis of femoral head (ONFH) is a disabling condition of young individuals with ill-defined etiology and pathogenesis. Remains untreated, about 70-80% of the patients progress to secondary hip arthritis. Both operative and nonoperative treatments have been described with variable success rate. Early diagnosis and treatment is the key for success in preserving the hip joint. Once femoral head collapses (>2 mm) or if there is secondary degeneration, hip conservation procedures become ineffective and arthroplasty remains the only better option. We reviewed 157 studies that evaluate different treatment modalities of ONFH and then a final consensus on treatment was made.

Summary of the various treatments for osteonecrosis of the femoral head by mechanism: A review

Osteonecrosis of the femoral head (ONFH), also known as femoral head avascular necrosis, is a pathological state with a number of possible etiologies including steroid administration, alcohol abuse, traumatic events, vascular injury and idiopathic origins. ONFH causes a reduction in the vascular supply to the subchondral bone of the femoral head, which results in osteocyte death and the collapse of the articular surface. Treatments for ONFH include non-weight-bearing therapy, physical support, the promotion of osteoclast apoptosis, and the reduction of osteoblast and osteocyte apoptosis. The aim of the present review was to summarize the treatments for ONFH by mechanism from a new perspective and to describe the condition with an emphasis on treatment options.

Hip osteonecrosis: does prior hip surgery alter outcomes compared to an initial primary total hip arthroplasty?

The purpose of this study was to assess the clinical and radiographic outcomes of total hip arthroplasty (THA) in patients who had osteonecrosis to see if prior hip preserving surgery affected outcomes. Implant survivorship, Harris hip scores, and radiographic outcomes were compared between 87 patients (92 hips) who had undergone prior hip preserving procedures and 105 patients (121 hips) who had only undergone THA. Patients were also sub-stratified into low- and high-risk groups for osteonecrosis. At a mean follow-up of 75 months, there were no significant differences in survivorship, clinical, and radiographic outcomes among the cohorts. Higher revision rates were associated with patients who were in the high-risk group. The authors believe that hip joint preserving procedures may not adversely affect the outcomes of later THA in patients with osteonecrosis.

Core decompression in combination with nano-hydroxyapatite/polyamide 66 rod for the treatment of osteonecrosis of the femoral head

BACKGROUND

The aim of this study was to investigate the effectiveness of core decompression in combination with a nano-hydroxyapatite/polyamide 66 (n-HA/PA66) rod and a porous bioglass bone graft for the treatment of osteonecrosis of the femoral head (ONFH).

METHODS

Sixty-four patients (84 hips) with ONFH were allocated to a program of either core decompression (CD) in combination with a n-HA/PA66 rod and a porous bioglass bone graft (treatment group) or CD with an autologous cancellous bone graft (control group). Clinical and radiographic retrospective follow-ups were performed on all patients with the prospectively collected data.

RESULTS

The overall clinical failure rate in the treatment group (9/38, 23.68%) was lower than that of the control group (24/46, 52.17%) (p < 0.05). Harris hip scores (HHS) were significantly increased in both groups post-surgery (p < 0.05). There was a significant difference between the two groups on HHS improvement for Steinberg IIC and IIIA (p < 0.05 and p < 0.001, respectively). The visual analogue scale (VAS) was significantly decreased in both groups post-surgery (p < 0.05). Especially, significant difference in the VAS improvement was observed between the groups for IIB, IIC and IIIA (p < 0.05, p < 0.05 and p < 0.01, respectively).

CONCLUSIONS

Core decompression combined with the implantation of a n-HA/PA66 rod and a bioglass bone graft can significantly decrease hip pain, improve hip function, and prevent the collapse of the femoral head in patients with ONFH. As the effectiveness of this approach appears to vary with Steinberg stage, we suggest that this treatment procedure may be suitable for patients with early to middle stage ONFH.

Osteonecrosis of the femoral head

Symptomatic hip osteonecrosis is a disabling condition with a poorly understood aetiology and pathogenesis. Numerous treatment options for hip osteonecrosis are described, which include non-operative management and joint preserving procedures, as well as total hip replacement (THR). Non-operative or joint preserving treatment may improve outcomes when an early diagnosis is made before the lesion has become too large or there is radiographic evidence of femoral head collapse. The presence of a crescent sign, femoral head flattening, and acetabular involvement indicate a more advanced-stage disease in which joint preserving options are less effective than THR. Since many patients present after disease progression, primary THR is often the only reliable treatment option available. Prior to the 1990s, outcomes of THR for osteonecrosis were poor. However, according to recent reports and systemic reviews, it is encouraging that with the introduction of newer ceramic and/or highly cross-linked polyethylene bearings as well as highly-porous fixation interfaces, THR appears to be a reliable option in the management of end-stage arthritis following hip osteonecrosis in this historically difficult to treat patient population.

Cite this article: Bone Joint J 2013;95-B, Supple A:46–50.

Digital subtraction angiography in selection of the vascularized greater trochanter bone grafting for treatment of osteonecrosis of femoral head

The aim of this report is to present our experience on the use of the digital subtraction angiography (DSA) in selection of the vascularized greater trochanter bone grafting for the treatment of the osteonecrosis of femoral head (ONFH) in early stages. Between January 2005 and June 2007, DSA was used to evaluate the blood perfusion of the early stages ONFH in 32 patients (45 hips). There were 18 males and 14 females with an average age of 30 years old. Twenty-one hips were in ARCO stage I, and 24 in ARCO stage II. The arterial blood supply insufficiency was found in 22 hips by DSA, and the venous stasis in 23 hips. The hips with artery blood supply insufficiency received the vascularized greater trochanter bone grafting, and the hips with the venous stasis received the core decompression. All of patients were followed-up with an average of 4.8 years (ranging 2.4-6.6 years). The preoperative Harris Hip score (HHS) in the patients with arterial blood supply insufficiency was 48.18 ± 7.81 and the postoperative HHS was 93.27 ± 3.03. The preoperative HHS in the patients with venous stasis was 44.04 ± 6.40, and the postoperative HHS 92.65 ± .93. The postoperative DSA showed an improved perfusion of the femoral head in 44 hips. Our experience showed that DSA would help to select the appropriate procedure for treatment of ONFH in the early stage.

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.

The effect of core decompression on local expression of BMP-2, PPAR-γ and bone regeneration in the steroid-induced femoral head osteonecrosis

Background

To investigate the efficacy of the sole core decompression surgery for the treatment of steroid-induced femoral head osteonecrosis.

Methods

The model was established by administration of steroids in combination with horse serum. The rabbits with bilateral femoral head osteonecrosis were randomly selected to do the one side of core decompression. The other side was used as the sham. Quantitative RT-PCR and western blot techniques were used to measure the local expression of BMP-2 and PPAR-γ. Bone tissues from control and operation groups were histologically analyzed by H&E staining. The comparisons of the local expression of BMP-2 and PPAR-γ and the bone regeneration were further analyzed between different groups at each time point.

Results

The expression of BMP-2 in the osteonecrosis femoral head with or without decompression was significantly lower than that in normal animals. BMP-2 expression both showed the decreasing trend with the increased post-operation time. No significant difference of BMP-2 expression occurred between femoral head osteonecrosis with and without decompression. The PPAR-γ expression in the femoral head osteonecrosis with and without core decompression both was significantly higher than that in control. Its expression pattern showed a significantly increased trend with increased the post-operation time. However, there was no significant difference of PPAR-γ expression between the femoral head osteonecrosis with and without decompression at each time point. Histopathological analysis revealed that new trabecular bone and a large number of osteoblasts were observed in the steroid-induced femoral head osteonecrosis with lateral decompression at 8 weeks after surgery, but there still existed trabecular bone fractures and bone necrosis.

Conclusions

Although decompression takes partial effect in promoting bone regeneration in the early treatment of femoral head osteonecrosis, such an effect does not significantly improve or reverse the pathological changes of femoral head necrosis. Thus, the long-term effect of core decompression in the treatment of steroid-induced femoral head osteonecrosis is not satisfactory.