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

Optimizing indications of impacting bone allograft transplantation in osteonecrosis of the femoral head

AIMS

The aim of this study was to report the medium-term outcomes of impaction bone allograft and fibular grafting for osteonecrosis of the femoral head (ONFH) and to define the optimal indications.

METHODS

A total of 67 patients (77 hips) with ONFH were enrolled in a single centre retrospective review. Success of the procedure was assessed using the Harris Hip Score (HHS) and rate of revision to total hip arthroplasty (THA). Risk factors were studied, including age, aetiology, duration of hip pain, as well as two classification systems (Association Research Circulation Osseous (ARCO) and Japanese Investigation Committee (JIC) systems).

RESULTS

After a mean follow-up period of 8.61 years (SD 1.45), 81.3% (52/64) of enrolled cases had a good or excellent HHS at latest follow-up (declining to 76.0% (38/50) for those with more than eight years of follow-up). Overall survival was 92.1% at eight years' follow-up (95% CI 83.2% to 96.4%). A total of 12 hips (19.0%) failed (reoperation or HHS < 70 points) at final follow-up. Rate of success was adversely affected by increasing age, duration of pain, and more severe disease as measured using the ARCO and JIC classifications, but not by aetiology of the ONFH.

CONCLUSION

We report favourable medium-term results of this procedure. Best outcomes can be expected in patients matching the following indications: younger than 40 years; less 12-month hip pain before surgery; femoral head collapse being less than 2 mm; and integrated lateral wall of femoral head. Cite this article: Bone Joint J 2020;102-B(7):838-844.

Modified technique of advanced core decompression for treatment of femoral head osteonecrosis

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is a destructive condition most commonly affecting young and middle-aged patients. The leading consequence of ONFH is often a significant articular disability. Effective joint-preserving surgical treatments are urgently needed for patients with early stage ONFH when outcomes of treatment are in general better than the advanced stage disease.

AIM

To introduce a new surgery procedure called percutaneous expanded core decompression and mixed bone graft technique, which is a new way of joint-preserving surgical treatments.

METHODS

The clinical data of 6 patients with ONFH diagnosed and treated with the procedure called percutaneous expanded core decompression and mixed bone graft technique at The First Hospital of Qiqihar from March 2013 to August 2019 were retrospectively analyzed; the follow-up ended in December 2019.

RESULTS

There were 6 male patients with an average age of 43 years in our study. Gratifying results have been obtained from the comparison of Harris hip score, visual analogue scale, and imaging examination before and after operation.

CONCLUSION

This new modified technique is simple, safe, and reliable. No serious perioperative complications were observed in our cases. Advantages of the single blade expandable reamer are obvious. The adjuvant substance is inexpensive and easy to obtain. Thus, this technique is an effective joint-preserving surgical treatment for patients with early stage of ONFH.

Management of osteonecrosis of the femoral head

Aims

Earlier studies dealing with trends in the management of osteonecrosis of the femoral head (ONFH) identified an increasing rate of total hip arthroplasties (THAs) and a decreasing rate of joint-preserving procedures between 1992 and 2008. In an effort to assess new trends in the management of this condition, this study evaluated the annual trends of joint-preserving versus arthroplasties for patients aged < or > 50 years old, and the incidence of specific operative management techniques.

Methods

A total of 219,371 patients with ONFH were identified from a nationwide database between 1 January 2009 and 31 December 2015. The mean age was 54 years (18 to 90) and 105,298 (48%) were female. The diagnosis was made using International Classification of Disease, Ninth revision, Clinical Modification (ICD-9-CM) and Tenth Revision, Clinical Modification (ICD-10-CM) procedure codes. The percentage of patients managed using each procedure during each year was calculated and compared between years. The trends in the use of the types of procedure were also evaluated.

Results

The rate of joint-preserving procedures was significantly higher in patients aged < 50 years compared with those aged > 50 years (4.93% vs 1.52%; p < 0.001). For the overall cohort, rates of arthroplasty were far greater than those for joint-preserving procedures. THA was the most commonly performed procedure (291,114; 94.03%), while osteotomy (3,598; 1.16%), partial arthroplasty (9,171; 2.96%), core decompression (1,200; 0.39%), and bone graft (3,026; 0.98%) were performed markedly less frequently. The annual percentage of patients managed using a THA (93.56% to 89.52%; p < 0.001), resurfacing (1.22% to 0.19%; p < 0.001), and osteotomy (1.31% to 1.05%; p < 0.001) also decreased during the study period.

Conclusion

We found that patients with ONFH have been most commonly managed with non-joint-preserving procedures. Our findings provide valuable insight into the current management of this condition and should increase efforts being made to save the hip joint. Cite this article: Bone Joint J 2020;102-B(7 Supple B):122–128.

Nontraumatic Osteonecrosis of the Femoral Head: Where Do We Stand Today?: A 5-Year Update

➢. Clinicians should exercise a high level of suspicion in at-risk patients (those who use corticosteroids, consume excessive alcohol, have sickle cell disease, etc.) in order to diagnose osteonecrosis of the femoral head in its earliest stage. ➢. Nonoperative treatment modalities have generally been ineffective at halting progression. Thus, nonoperative treatment is not appropriate in early stages when one is attempting to preserve the native joint, except potentially on rare occasions for small-sized, medially located lesions, which may heal without surgery. ➢. Joint-preserving procedures should be attempted in early-stage lesions to save the femoral head. ➢. Cell-based augmentation of joint-preserving procedures continues to show promising results, and thus should be considered as an ancillary treatment method that may improve clinical outcomes. ➢. The outcomes of total hip arthroplasty in the setting of osteonecrosis are excellent, with results similar to those in patients who have an underlying diagnosis of osteoarthritis.

Digital Subtraction Angiography and Magnetic Resonance Imaging-Based Staging of Circulatory Obstruction in the Femoral Head During Osteonecrosis of the Femoral Head Development

INTRODUCTION

Nontraumatic osteonecrosis of the femoral head (NONFH) is a common and difficult disease in orthopedics. Magnetic resonance imaging (MRI) assessment of NONFH and bone marrow edema was combined with digital subtraction angiography (DSA) to evaluate the circulatory status of NONFH in different Association Research Circulation Osseous stages. Based on the circulatory obstruction status (venous stasis, arterial ischemia, and arterial occlusion), appropriate perioperative management was adopted to achieve hip joint preservation and effectively delay the time for total hip arthroplasty in young patients.

METHODS

From January 2013 to March 2019, 41 orthopedic patients were evaluated for medical imaging. Sixty-one ONFH cases were enrolled. The inclusion criteria include: (1) Clear diagnosis of osteonecrosis of the femoral head. (2) No history of infection in the affected hip, no history of hip surgery, and no congenital hip diseases. The patients enrolled in this study were 8 women and 33 men between the ages of 19 and 64 years (mean, 39.25 ± 8.90 years). Preoperative X-ray, computed tomography, MRI, DSA, and histological data were taken.

RESULTS

The combination of DSA and MRI can efficiently show blood supply changes in the femoral head of NONFH patients at different Association Research Circulation Osseous stages; and also can possibly reveal the causes and development of NONFH. Different stages of circulatory obstruction of the femoral head can be clearly distinguished and used to determine the required perioperative management, thus yielding successful surgical outcomes.

CONCLUSIONS

The existing classification systems do not fully reflect the progression of circulatory obstruction in ONFH. Each stage of NONFH development has its own characteristics circulatory obstruction. Early-stage NONFH displays characteristic venous stasis of the femoral head, whereas advanced stage NONFH is characterized by insufficient arterial blood supply to the femoral head. Corresponding NONFH treatment strategies should be considered based on their specific circulatory status. This work also provides guidance and recommendations for adopting corresponding femoral head preserving strategies for young patients in different NONFH circulatory status.

Did Osteoblastic Cell Therapy Improve the Prognosis of Pre-fracture Osteonecrosis of the Femoral Head? A Randomized, Controlled Trial

BACKGROUND

In patients with nontraumatic osteonecrosis of the femoral head (ONFH), implantation of bone marrow aspirate concentrate (BMAC) could delay the progression of osteonecrosis and improve symptoms in pre-fracture ONFH. However, the BMAC content, especially in osteoblastic stem cells, could have an important individual variability. An autologous osteoblastic cell product could improve the effect of such cell-based therapy.

QUESTIONS/PURPOSES

(1) Does autologous osteoblastic cell therapy decrease the likelihood of progression to subchondral fracture with or without early collapse corresponding to Association Research Circulation Osseous (ARCO) classification Stage III or higher, and provide a clinically important pain improvement compared with BMAC treatment alone? (2) Were patients treated with osteoblastic cell therapy less likely to undergo subsequent THA? (3) What proportion of patients in the treatment and control groups experienced adverse events after surgery?

METHODS

Between 2004 and 2011, we treated 279 patients for Stage I to II hip osteonecrosis (ON) with surgery. During that time, our general indications for surgery in this setting included non-fracture ON lesions. To be eligible for this randomized, single-blind trial, patients needed to have an ONFH Stage I or II; we excluded those with traumatic ONFH, hemoglobinopathies and positive serology for hepatitis B, C or HIV. Of those treated surgically for this diagnosis during the study period, 24% (67) agreed to participate in this randomized trial. Hips with pre-fracture ONFH were randomly treated with a core decompression procedure associated with either implantation of a BMAC (BMAC group; n = 26) or osteoblastic cell (osteoblastic cell group; n = 30). The groups were not different in terms of clinical and imaging characteristics. The primary study outcome was treatment response, defined as the absence of progression to subchondral fracture stage (ARCO stage III or higher) plus a clinically important pain improvement defined as 1 cm on a 10-cm VAS. The secondary endpoint of interest was the frequency in each group of subsequent THA and the frequency of adverse events. The follow-up duration was 36 months. We used an as-treated analysis (rather than intention-to-treat) for our efficacy endpoint, and an intention-to-treat analysis for adverse events. Overall, 26 of 26 patients in the BMAC group and 27 of 30 in the osteoblastic cell group completed the trial.

RESULTS

At 36 months, no clinically important differences were found in any study endpoint. There was no difference in the proportion of patients who had progressed to fracture (ARCO stage III or higher; 46% of the BMAC hips [12 of 26] versus 22% in the hips with osteoblastic cells [six of 27], hazard ratio, 0.47 [95% CI 0.17 to 1.31]; p = 0.15). There was no clinically important difference in VAS pain scores. No differences were found for either the WOMAC or the Lequesne indexes. With the numbers available, there was no difference in the proportion of patients in the groups who underwent THA at 36 months 15% (four of 27) with osteoblastic cells versus 35% (nine of 26) with BMAC; p = 0.09 With the numbers available, we found no differences between the treatment and control groups in terms of the frequencies of major adverse events.

CONCLUSIONS

We found no benefit to osteoblastic cells over BMAC in patients with pre-collapse ONFH; side effects were uncommon and generally mild in both groups. This study could be used as pilot data to help determine sample sizes for larger (presumably multicenter) randomized controlled trials. However, this novel treatment cannot be recommended in routine practice until future, larger studies demonstrate efficacy.

LEVEL OF EVIDENCE

Level II, therapeutic study.

Single approach to double-channel core decompression and bone grafting with structural bone support for treating osteonecrosis of the femoral head in different stages

BACKGROUND

We created a novel method-single approach to double-channel core decompression and bone grafting with structural bone support (SDBS)-to treat early-stage osteonecrosis of the femoral head (ONFH) by improving the Phemister technique. This study aimed to evaluate the results of SDBS for early-stage ONFH.

METHODS

Altogether, 53 patients (73 hips) were treated using SDBS during 2016-2018. Bilateral (20 patients) and unilateral (33 patients = 18 left hips, 15 right hips) ONFH was diagnosed. According to the Association Research Circulation Osseous classification stages, the femoral heads were staged as IIB (n = 15), IIC (n = 19), IIIA (n = 34), IIIB (n = 4), and IIIC (n = 1). The Harris hip score was used to evaluate the hips' clinical function, computed tomography to evaluate subchondral fractures, and plain radiography to assess the extent of femoral head collapse.

RESULTS

The average follow-up was 20.71 ± 6.65 months (6-36 months). At the patients' last follow-up, 4 hips were found to require arthroplasty. Thus, the overall femoral head survival rate was 94.52% (69/73). Also, the overall Harris score (84.44 ± 14.57) was significantly higher than that preoperatively (77.67 ± 14.37) (P = 0.000). The combined excellent and good rate (76.71%) was significantly higher than that preoperatively (38.36%) (P = 0.000). Imaging showed that 16 femoral heads had some ONFH progression. The average length of stay was 6.15 ± 0.86 days. The average incision measured 2.69 ± 0.30 cm. Intraoperative blood loss was 61.20 ± 4.81 ml. There were no complications during or after the operation.

CONCLUSION

SDBS is an effective method for treating early-stage ONFH. It is a hip-preserving surgical approach to slow/prevent ONFH progression.

MiR-596 inhibits osteoblastic differentiation and cell proliferation by targeting Smad3 in steroid-induced osteonecrosis of femoral head

Background

It is reported that miR-596 has a potential diagnostic value for non-traumatic osteonecrosis of the femoral head (NOFH), but its underlying mechanisms in NOFH is unclear.

Methods

The expression of miR-596 and Smad3 was detected by western blot and quantitative real-time PCR. The relationship between the two molecules was explored using Dual-Luciferase Reporter Assay. Glucocorticoid (GC)—dexamethasone, was used to induce bone marrow mesenchymal stem cell (BMSC) osteogenic differentiation, and the effects of miR-596 on BMSC osteogenic differentiation and proliferation were determined.

Results

MiR-596 expression was upregulated, while Smad3 expression was inhibited in the bone marrow samples of patients with steroid-induced osteonecrosis of femoral head (SANFH). Overexpression of miR-596 inhibited the proliferation and osteogenic differentiation of BMSCs induced by GC. Meanwhile, the opposite results were observed in the miR-596 inhibitor group. In addition, Smad3 was a target gene of miR-596, and negatively regulated by miR-596. The promotion effect of the miR-596 inhibitor on BMSC proliferation and osteogenic differentiation was reversed by si-Smad3.

Conclusion

MiR-596 can suppress GC-BMSC osteoblastic differentiation and proliferation by regulating Smad3 expression.

β-ecdysone promotes osteogenic differentiation of bone marrow mesenchymal stem cells

BACKGROUND

β-ecdysone (βEcd) has numerous pharmacological effects, although its role in the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) has not yet been explored.

METHODS

In cell experiments, BMSCs were induced to differentiate by osteogenic induction medium (OIM) or βEcd. In animal experiments, an osteonecrosis of the femoral head (ONFH) rat model was established using lipopolysaccharide plus methylprednisolone and treating the rats with βEcd. The osteogenic differentiation capacity of human BMSCs (hBMSCs) was analyzed by alkaline phosphatase and alizarin red S staining. Histopathological changes in rat femoral head tissues were observed by hematoxylin and eosin staining. The expression levels of RUNX2, COL1A1, OCN and phosphorylated Akt in BMSCs from rat femoral head tissues were measured by a quantitative real-time polymerase chain reaction or western blot analysis.

RESULTS

Alkaline phosphatase activity and calcium nodules in the βEcd-treated BMSC group dose-dependently increased compared to those in the control and OIM groups. The hematoxylin and eosin staining results indicated that femoral head tissues of ONFH rats showed typical osteonecrosis, which could be ameliorated by βEcd. Western blot, quantitative real-time polymerase chain reaction and immunohistochemistry assays demonstrated that the expression levels of RUNX2, COL1A1 and OCN in hBMSCs and femoral head tissue models were obviously increased after βEcd treatment, and phosphoinositide 3-kinase and Akt phosphorylation were also increased.

CONCLUSIONS

βEcd may be beneficial for the recovery of ONFH patients by accelerating osteogenic differentiation of BMSCs, which may be a novel therapy for related diseases.

Comparison of surgical dislocation and impacting bone graft and surgical dislocation and rotational osteotomy for the treatment of ARCO III femoral head necrosis

Hip preserving procedures are still a challenge in late-stage osteonecrosis of femoral head (ONFH) patients. We aimed to compare the clinical outcomes of surgical dislocation and impaction bone graft and surgical dislocation and rotational osteotomy for treatment of ONFH in Association Research Circulation Osseous (ARCO) stage III patients.We retrospectively reviewed 30 ARCO stage III patients (33 hips) who had surgical dislocation and impaction bone graft or surgical dislocation and rotational osteotomy in our center from June 2012 to December 2017. Baseline characteristics, clinical evaluation using Harris score and radiologic evaluation up to 12 months after surgery were recorded and compared.Fifteen patients (17 hips) were in the surgical dislocation and impaction bone graft group and 15 patients (16 hips) were in the surgical dislocation and rotational osteotomy group. No significant differences in age, gender, etiology, ARCO stage, duration of illness, operation time, and length of hospitalization were observed between the 2 groups. Compared to preoperation Harris score, the Harris score of 6 months postoperation and 12 months postoperation significantly improved. At 12 months postoperation, the excellent and good rate was 76.5% in the impaction bone graft group and 87.5% in the rotational osteotomy group. No significant difference in Harris scores was detected in the 2 groups.Surgical dislocation and impaction bone graft and surgical dislocation and rotational osteotomy had satisfactory 1-year efficacy for ARCO III ONFH patients. Surgical dislocation and rotational osteotomy had better short-term efficacy than surgical dislocation and impaction bone graft.

High failure rate after Beta-tricalcium phosphate grafting for the treatment of femoral head osteonecrosis: a retrospective analysis

Background

Non-vascularized bone grafting is a promising head-preserving technique for younger patients diagnosed as non-traumatic osteonecrosis of the femoral head (NONFH). Among the various types of bone grafting techniques, “light-bulb” procedure grafting with synthetic bone substitute is an attractive option. We aimed to assess the effectiveness of using beta-tricalcium phosphate (β-TCP) for the treatment of pre-collapse and early post-collapse lesions NONFH.

Methods

From April 2010 to June 2014, 33 patients (47 hips) with NONFH were treated using the afore-mentioned technique. The clinical and radiological outcomes were recorded and compared statistically between pre- and post-operation. Harris hip score (HHS) was used to evaluate the clinical results, and Association Research Circulation Osseous (ARCO) stage was applied to assess the radiological outcomes.

Results

The 5-years survival rate of using β-TCP grafting was accounting for 25.5%. HHS was decreased from 78.47 to 52.87 points, and a very significant worsening of radiological results were revealed (P <  0.05). Two hips collapsed more than 2 mm were awaiting for THA, and 33 of the 47 hips had converted to THAs in an average time to failure of 24.24 months postoperatively. Meanwhile, only 4 hips survived without collapse, and 8 hips collapsed less than 2 mm. After surgery, the time onset of head collapse was 3.65 months on average, and the first conversion to THA was performed at 5 months postoperative.

Conclusions

Our results suggest that “light-bulb” procedure grafting with β-TCP sticks presented with a high failure rate in the early postoperative period. It is not proposed for the treatment of pre-collapse and early post-collapse lesions NONFH.

Steroid-induced osteonecrosis of the femoral head reveals enhanced reactive oxygen species and hyperactive osteoclasts

Steroid-induced osteonecrosis of the femoral head (ONFH) is a progressive bone disorder which typically results in femoral head collapse and hip joint dysfunction. It is well-accepted that abnormal osteoclast activity contributes to loss of bone structural integrity and subchondral fracture in ONFH. However, the pathophysiologic mechanisms underlying the recruitment and hyperactivation of osteoclasts in ONFH remain incompletely understood. We assessed the changes of reactive oxygen species (ROS) level and subsequent osteoclast alterations in steroid-induced osteonecrotic femoral heads from both patients and rat ONFH models. When compared with healthy neighboring bone, the necrotic region of human femoral head was characterized by robust up-regulated expression of osteoclast-related proteins [cathepsin K and tartrate-resistant acid phosphatase(TRAP)] but pronounced down-regulation of antioxidant enzymes (catalase, γ-glutamylcysteine synthetase [γ-GCSc], and superoxide dismutase 1 [SOD1]). In addition, the ratio of TNFSF11 (encoding RANKL)/TNFRSF11B (encoding OPG) was increased within the necrotic bone. Consistently, in rat ONFH models induced by methylprednisolone (MPSL) and imiquimod (IMI), significant bone loss in the femoral head was observed, attributable to increased numbers of TRAP positive osteoclasts. Furthermore, the decreased expression of antioxidant enzymes observed by immunoblotting was accompanied by increased ex-vivo ROS fluorescence signals of dihydroethidium (DHE) in rat ONFH models. Therefore, this study lends support to the rationale that antioxidant agents may be a promising therapeutic avenue to prevent or mitigate the progression of steroid-induced ONFH by inhibiting ROS level and hyperactive osteoclasts.

Chinese herbal Huo-Gu formula for the treatment of steroid-associated osteonecrosis of femoral head: A 14-year follow-up of convalescent SARS patients

Purpose

The coronavirus disease 2019 (COVID-19) reminds us of the severe acute respiratory syndrome (SARS) outbreak in 2003, and up to date, corticosteroid is commonly administrated to severe patients with COVID-19. Osteonecrosis of the femoral head (ONFH) is a common disabling complication among convalescent SARS patients who received corticosteroid therapy. In China, a considerable number of convalescent SARS patients with steroid-associated ONFH had undergone conservative treatment by traditional Chinese medicine, and this study aims to evaluate the long-term results of a spleen-invigorating Huo-Gu formula (HGF) therapy in these patients.

Participants and methods

A total of 33 convalescent SARS patients (9 males and 24 females) with bilateral steroid-associated ONFH (66 hips) were enrolled in this study. All patients received oral HGF therapy for 6 months when they were confirmed the diagnosis of steroid-associated ONFH. They had been regularly followed up at an interval of 1 year. Harris hip score and medical imaging modalities, including plain radiography, computed tomography and magnetic resonance imaging, were performed to evaluate the outcomes.

Results

Based on average 14 years of follow-up of HGF therapy (ranging from 6 to 16 years), 38 hips (57%) among the 66 hips developed definite osteoarthritis, and 14 hips (26%) in 53 precollapse hips (Association Research Circulation Osseous [ARCO] Stage I or II) progressed to femoral head collapse (ARCO Stage III or IV). Only five patients (also 5 hips) underwent total hip arthroplasty, and the mean hip survival time was over 15 years by the Kaplan-Meier analysis. We observed a mean Harris hip score of 63 points, which represented the reserve of 55% in pain score and 70% in physical function score. The severity of groin pain was not correlated to the severity of osteoarthritis.

Conclusion

Chinese herbal HGF therapy demonstrates beneficial effects on preventing femoral head collapse, delaying total hip arthroplasty, and maintaining physical function in the treatment of steroid-associated ONFH. HGF therapy might be therefore a good alternative for the treatment of steroid-associated ONFH secondary to rheumatologic and infection diseases.

Translational potential of the article

HGF therapy might be a good alternative for the treatment of steroid-associated ONFH secondary to rheumatologic and infectious diseases.

The 2019 Revised Version of Association Research Circulation Osseous Staging System of Osteonecrosis of the Femoral Head

BACKGROUND

The Association Research Circulation Osseous (ARCO) presents the 2019 revised staging system of osteonecrosis of the femoral head (ONFH) based on the 1994 ARCO classification.

METHODS

In October 2018, ARCO established a task force to revise the staging system of ONFH. The task force involved 29 experts who used a web-based survey for international collaboration. Content validity ratios for each answer were calculated to identify the levels of agreement. For the rating queries, a consensus was defined when more than 70% of the panel members scored a 4 or 5 rating on a 5-point scale.

RESULTS

Response rates were 93.1%-100%, and through the 4-round Delphi study, the 1994 ARCO classification for ONFH was successfully revised. The final consensus resulted in the following 4-staged system: stage I-X-ray is normal, but either magnetic resonance imaging or bone scan is positive; stage II-X-ray is abnormal (subtle signs of osteosclerosis, focal osteoporosis, or cystic change in the femoral head) but without any evidence of subchondral fracture, fracture in the necrotic portion, or flattening of the femoral head; stage III-fracture in the subchondral or necrotic zone as seen on X-ray or computed tomography scans. This stage is further divided into stage IIIA (early, femoral head depression ≤2 mm) and stage IIIB (late, femoral head depression >2 mm); and stage IV-X-ray evidence of osteoarthritis with accompanying joint space narrowing, acetabular changes, and/or joint destruction. This revised staging system does not incorporate the previous subclassification or quantitation parameters, but the panels agreed on the future development of a separate grading system for predicting disease progression.

CONCLUSION

A staging system has been developed to revise the 1994 ARCO classification for ONFH by an expert panel-based Delphi survey. ARCO approved and recommends this revised system as a universal staging of ONFH.

Results of advanced core decompression in patients with osteonecrosis of the femoral head depending on age and sex-a prospective cohort study

Background

Core decompression is a common surgical technique to treat osteonecrosis of the femoral head. The aim of this study is to evaluate the effect of the parameters “age” and “sex” on the outcome of this type of treatment.

Methods

A prospective cohort study was performed. Eighty-six osteonecrotic hips with a mean follow-up of 32.5 months (± 24.8) after advanced core decompression were analysed regarding age- and sex-dependent treatment failure. Additionally, the modified Harris Hip Score and Numeric Rating Scale were compared regarding the parameters age and sex.

Results

The mean hip survival of the male participants was 51.3 months (39.4% treatment failure), whereas females presented a longer, thus not significant, mean survival of 61.4 months (30% therapy failure; p = 0.48). The further evaluation revealed significantly better survival in the patients aged < 40 years (mean survival 66.09 months, 16% treatment failure) in comparison to those aged ≥ 40 years (mean survival 50.14 months, 46% therapy failure; p = 0.03). The modified Harris Hip Score and Numeric Rating Scale results of patients whose treatment did not fail during the study period were similar, irrespective of the patient’s sex or age.

Conclusions

The study shows that the number of therapy failures is significantly higher in older patients, with 40 years of age marking the borderline. Patients’ sex does not seem to affect the outcome of treatment, and postoperative clinical scores appear to be identical with individuals not affected by therapy failure. Since age and sex are unalterable parameters, the study helps to provide valuable predictions regarding the chances of long-term hip survival after treatment of osteonecrosis.

Effect of Allogeneic Cell-Based Tissue-Engineered Treatments in a Sheep Osteonecrosis Model

Osteonecrosis of the femoral head (ONFH) is defined as a tissue disorder and successive subchondral bone collapse resulting from an ischemic process, which may progress to hip osteoarthritis. Cell therapy with multipotent bone marrow mesenchymal stromal cells (BM-MSC) of autologous origin appears to be safe and has shown regenerative potential in previous preclinical and clinical studies. The use of allogeneic cells is far more challenging, but may be a promising alternative to use of autologous cells. Moreover, an optimized dosage of cells from an allogeneic source is needed to obtain off-the-shelf tissue engineering products (TEPs). The purpose of this study was to evaluate the efficacy of a TEP composed of undifferentiated ex vivo expanded BM-MSC of allogeneic origin, combined with bone matrix particles in variable doses. A comparative analysis of TEP's bone regenerative properties against its autologous counterpart was performed in an early-stage ONFH preclinical model in mature sheep. Allogeneic BM-MSC groups demonstrated bone regeneration capacity in osteonecrotic lesions equivalent to autologous BM-MSC groups 6 weeks after treatment. Likewise, stimulation of bone regeneration by a low cell dose of 0.5 × 10⁶ BM-MSC/cm³ was equivalent to that of a high cell dose, 5 × 10⁶ BM-MSC/cm³. Neither local nor systemic immunological reactions nor tumorigenesis were reported, strengthening the safety profile of allogeneic BM-MSC therapy in this model. Our results suggest that low-dose allogeneic BM-MSC is sufficient to promote bone regeneration in femoral head osteonecrotic lesions, and should be considered in translation of new allogeneic cell-based TEPs to human clinics. Impact statement Cell therapy and tissue engineering hold promise as novel regenerative therapies for musculoskeletal diseases, and particularly in bone regeneration strategies. In this article, we report the evaluation of the efficacy of an allogeneic cell-based tissue engineering product (TEP) in an early-stage osteonecrosis of the femoral head preclinical model in skeletally mature sheep. Moreover, we demonstrate its bone regeneration capacity and safety in vivo and its equivalence to autologous counterparts. These findings have important implications for the translation of new allogeneic cell-based TEPs to human clinics.

A 3D printed porous titanium alloy rod with biogenic lamellar configuration for treatment of the early-stage femoral head osteonecrosis in sheep

There is no ideal implant for mechanical strut on early-stage osteonecrosis of the femoral head (ONFH) after core decompression. In this study, a biogenic trabecular porous titanium rod with lamellar configuration was designed and fabricated using selective laser melting technique. Early-stage ONFH of sheep induced by cryo-insult were dealt with core decompression combined with rod insertion (Rod group) and core decompression alone (CD group) after X-ray evaluation was used to assess the necrotic region one months after cryo-intervention. Bone integration and ingrowth of the two groups were investigated and compared. Early-stage ONFH intervened with the rod gained better bone ingrowth than CD 3 and 6 months after the intervention, as evidenced by radiographic, micro-CT and histological evaluation. X-ray images showed compact integration between rods and peripheral bone, evidenced by no radiolucent lines encircling the rods at 3 and 6 months. Micro-CT and histological images showed that the new bone had grown into the centre of rods along the metal at 3 months, whereas the new bone grew mainly at the periphery of the decompressive channel. Micro-CT analysis show that the ratios of bone volume to total volume (BV/TV) of volume of interest (VOI) in Rod group was 890.0% and 438.1% higher than CD group at 3 (0.198 ± 0.0094 VS 0.020 ± 0.0058, p < 0.05, n = 3) and 6 (0.226 ± 0.0166 VS 0.042 ± 0.0061, p < 0.05, n = 3) months respectively. Histological analysis showed that the BV/TV of VOI in Rod group was 881.0% and 413.3% higher than CD group at 3 (0.206 ± 0.0102 VS 0.021 ± 0.0061, p < 0.05, n = 3) and 6 (0.231 ± 0.0156 VS 0.045 ± 0.0059, p < 0.05, n = 3) months respectively. The mechanical tests revealed that the maximum load of Rod group was 57.6% larger than CD group at 6 months (4505.25 ± 443.86 N VS 2858.25 ± 512.91 N, p < 0.05, n = 3). These favourable short-term results can provide insight on treatment of early-stage ONFH.

The Use of Platelet-Rich Plasma for the Treatment of Osteonecrosis of the Femoral Head: A Systematic Review

Background

As a pathological process, osteonecrosis of the femoral head (ONFH) is characterized by the avascularity of the femoral head, cellular necrosis, microfracture, and the collapse of the articular surface. Currently, critical treatment for early-stage ONFH is limited to core decompression. However, the efficacy of core decompression remains controversial. To improve the core decompression efficacy, regenerative techniques such as the use of platelet-rich plasma (PRP) were proposed for early-stage ONFH. As a type of autologous plasma containing concentrations of platelets greater than the baseline, PRP plays an important role in tissue repair, regeneration, and the differentiation of mesenchymal stem cells (MSCs). In this review, we present a comprehensive overview of the operation modes, mechanism, and efficacy of PRP for early-stage ONFH treatment.

Methods

We searched for relevant studies in the PubMed, Web of Science, and Embase databases. By searching these electronic databases, the identification of either clinical or experimental studies evaluating PRP, MSC, core decompression, and ONFH was our goal.

Results

Seventeen studies of PRP and avascular necrosis of the femoral head were evaluated in our review. Ten studies related to the possible mechanism of PRP for treating ONFH were reviewed. Seven studies of the operation modes of PRP in treating ONFH were identified. We reviewed the efficacy of PRP in treating ONFH systematically and made an attempt to compare the PRP operation modes in 7 studies and other operation modes in past studies for early-stage ONFH treatment.

Conclusion

PRP treats ONFH mainly through three mechanisms: inducing angiogenesis and osteogenesis to accelerate bone healing, inhibiting inflammatory reactions in necrotic lesions, and preventing apoptosis induced by glucocorticoids. In addition, as an adjunctive therapy for core decompression, the use of PRP is recommended to improve the treatment of early-stage ONFH patients, especially when combined with stem cells and bone grafts, by inducing osteogenic activity and stimulating the differentiation of stem cells in necrotic lesions.

Osteonecrosis of the femoral head due to brucellosis: a case report

BACKGROUND

Brucellosis is a zoonotic infection transmitted from infected animals to humans, osteonecrosis of the femoral head (ONFH) is a devastating disease that affects patients' life with pain, dysfunction of walking and always lead to total hip arthroplasty (THA). We presented a case of ONFH which was very likely due to the infection of Brucella spp.

CASE PRESENTATION

The patient was a 49 years-old male who was a herder living in Inner Mongolia, the northern part of China. He first showed recurrent fever then presented bilateral hip pain, which was confirmed to be brucellosis and ONFH on the right side of the hip. He was admitted to our center showed bilateral ONFH with the restrictive movement of both hips. We performed THA after it was confirmed that the infection has been cured. The patient can walk with the help of the walker the second day after surgery.

CONCLUSION

Brucellosis is still a common epidemic disease worldwide, which can lead to many complications, brucellosis arthritis is the most common complication of Brucellosis. Osteonecrosis of the femoral head can also present in the patients with brucellosis. All the patients presented with recurrent fever and hip pain, who is from the epidemic region, should be taken both septic arthritis and ONFH into consideration.

Therapeutic Applications of Genes and Gene-Engineered Mesenchymal Stem Cells for Femoral Head Necrosis

Osteonecrosis of the femoral head (ONFH) is a common and disabling joint disease. Although there is no clear consensus on the complex pathogenic mechanism of ONFH, trauma, abuse of glucocorticoids, and alcoholism are implicated in its etiology. The therapeutic strategies are still limited, and the clinical outcomes are not satisfactory. Mesenchymal stem cells (MSCs) have been shown to exert a positive impact on ONFH in preclinical experiments and clinical trials. The beneficial properties of MSCs are due, at least in part, to their ability to home to the injured tissue, secretion of paracrine signaling molecules, and multipotentiality. Nevertheless, the regenerative capacity of transplanted cells is impaired by the hostile environment of necrotic tissue in vivo, limiting their clinical efficacy. Recently, genetic engineering has been introduced as an attractive strategy to improve the regenerative properties of MSCs in the treatment of early-stage ONFH. This review summarizes the function of several genes used in the engineering of MSCs for the treatment of ONFH. Further, current challenges and future perspectives of genetic manipulation of MSCs are discussed. The notion of genetically engineered MSCs functioning as a "factory" that can produce a significant amount of multipotent and patient-specific therapeutic product is emphasized.

Icariin promotes osteogenic differentiation of BMSCs by upregulating BMAL1 expression via BMP signaling

Increasing research has demonstrated that expression of brain and muscle ARNT‑like 1 (BMAL1) and other circadian clock genes can be regulated by drugs and toxicants. We previously demonstrated that icariin, extracted from Herba Epimedii, sromotes osteogenic differentiation. However, the mechanism underlying the association between icariin and BMAL1 in osteogenic differentiation of bone marrow‑derived mesenchymal stem cells (BMSCs) remains unclear. The present study was designed with an aim to clarify the association between icariin and BMAL1 in osteogenic differentiation of BMSCs. The Cell Counting Kit‑8 assay was used to evaluate cell proliferation. The expression of bone morphogenetic protein 2 (BMP2), RUNX family transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osteocalcin (OC) and BMAL1 in BMSCs was evaluated by reverse transcription‑quantitative PCR and western blotting. ALP and Alizarin red S (ARS) staining were also performed. Icariin promoted BMSC proliferation, and upregulated expression of osteogenic genes and BMAL1. In addition, expression of the osteogenic genes BMP2, RUNX2, ALP and OC were upregulated by BMAL1 overexpression. Furthermore, we confirmed that BMAL1 deficiency suppressed osteogenic differentiation in BMSCs. Finally, ARS staining of BMAL1‑/‑ BMSCs revealed that BMAL1 was an essential intermediary in matrix mineralization during osteogenic differentiation. In conclusion, these results demonstrated that icariin promoted osteogenic differentiation through BMAL1‑BMP2 signaling in BMSCs. The present study thus described a novel target of icariin that has potential applications in the treatment of osteogenic disorders.

Microarray profiling of circular RNAs in steroid-associated osteonecrosis of the femoral head: Observational study

The aim of this study was to elucidate the molecular mechanisms and to identify the differential expression of circular RNAs (circRNAs) for steroid-associated osteonecrosis of the femoral head (SONFH) using bioinformatics analysis.circRNA microarray was performed with 3 SONFH tissues and the adjacent normal tissues, and differentially expressed circRNA were identified by limma package in R. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using the Database for Annotation, Visualization and Integrated Discovery database. In addition, a differentially expressed genes (DEG)-associated circRNA/microRNA (miRNA) interaction was predicted by combination of TargetScan and miRanda, and the circRNA/miRNA interaction network generated by the cytoscape software.A total of 647 differentially expressed circRNAs, including 433 upregulated and 214 downregulated circRNA were identified. The most enriched GO terms for upregulated and downregulated circRNA were extracellular matrix organization and leukocyte activation in biological process; extracellular matrix and spindle pole in cellular component; integrin binding and ATP binding in molecular function, and KEGG pathway enrichment analyses showed that the upregulated and downregulated circRNA were strongly associated with Protein digestion and absorption and Cell cycle. Moreover, a total of 212 differentially expressed messenger RNAs (mRNAs), including 113 upregulated and 99 downregulated genes were identified. In addition, from the analysis of miRNA, long noncoding RNAs, mRNA, and circRNA networks, we found that hsa_circ_0008136 and hsa_circ_0074758 were respectively the upregulated and downregulated circRNA with highest degrees.The identified circRNA and mRNA could be implicated in the progression of human SONFH. The findings could lead to a better understanding of SONFH pathogenesis.

Femoral Head and Neck Fenestration Through a Direct Anterior Approach Combined With Compacted Autograft for the Treatment of Early Stage Nontraumatic Osteonecrosis of the Femoral Head: A Retrospective Study

BACKGROUND

This study aimed to evaluate the effect of femoral head and neck fenestration combined with compacted autograft (light bulb procedure) through a direct anterior approach for early stage nontraumatic osteonecrosis of the femoral head.

METHODS

We conducted a retrospective cohort study investigating 66 hips undergoing the light bulb procedure through the direct anterior approach (light bulb group) and 59 hips undergoing traditional core decompression (control group). Visual analog scale pain scores and range of hip motion were evaluated before discharge to assess the quality of functional recovery. Follow-up was conducted at 6 weeks, 3 months, 6 months, and annually after surgery until 4 years. The clinical effectiveness was evaluated by Harris hip score and the University of California Los Angeles activity-level score. Patients were followed up with postoperative X-ray and computed tomography. Survival was compared between the 2 groups by radiographic progression and receiving total hip arthroplasty.

RESULTS

There was no significant difference in quality of functional recovery between the 2 groups. There were no significant differences in clinical outcomes within 1 year after surgery. Patients in the light bulb group had significantly better Harris hip scores and University of California Los Angeles activity-level scores from 2 years after surgery to the end of follow-up. During the 4-year follow-up, significantly fewer patients in light bulb group had radiographic progression (22.7% vs 44.1%) or received total hip arthroplasty (15.2% vs 30.5%).

CONCLUSIONS

The light bulb procedure through a direct anterior approach offers significantly better results for the treatment of early stage nontraumatic osteonecrosis of the femoral head compared with traditional core decompression.

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.

Prognosis after autologous peripheral blood stem cell transplantation for osteonecrosis of the femoral head in the pre-collapse stage: a retrospective cohort study

OBJECTIVES

Autologous peripheral blood stem cell (auto-PBSC) transplantation is an effective therapeutic for the osteonecrosis of the femoral head (ONFH) but without prognosis estimation. This study mainly aimed to (1) determine whether auto-PBSC transplantation is a promising option, (2) assess the risk of hip-preservation failure, (3) achieve a predictive model of femoral head survival after the intervention, and (4) eventually identify clinical indications for auto-PBSC transplantation in future.

METHODS

After reviewing the in-patient database of the First Affiliated Hospital of Zhejiang Chinese Medicine University from June 2012 to June 2014, 37 eligible patients with Association Research Circulation Osseous stage I or II ONFH who were receiving intra-arterial infusion of auto-PBSCs were recruited. A case form was designed to retrieve relevant data. Hip-preservation failure was defined as the endpoint. All participants were stratified by the categorical risk of collapse, which was statistically tested through log-rank analysis. All significant factors were evaluated using Cox proportional hazards regression model, and a predictive nomogram plot was generated.

RESULTS

In total, 47 hips were followed up for 53.96 ± 21.09 months; the median survival time was 60.18 months. Among the predictors, body mass index (BMI; P = 0.0015) and Harris hip score (HHS; P < 0.0001) independently affected femoral head survival. Patients with BMI ≥ 24 kg/m² exhibited a 2.58 times higher risk of hip-preservation failure [95% confidence interval (CI), 1.32-5.45] than those with BMI < 24 kg/m², whereas those with HHS ≥ 70 exhibited a 0.19 times lower risk (95% CI, 0.09-0.38) than those with HHS < 70. Hazard ratios associated with age (P = 0.042), BMI (P = 0.012), HHS (P = 0.022), and necrotic volume (P = 0.000) were 1.038 (95% CI, 1.001-1.075), 1.379 (95% CI, 1.072-1.773), 0.961 (95% CI, 0.928-0.994), and 1.258 (95% CI, 1.120-1.412), respectively. A nomogram plot (score test P = 0.000; C-index = 0.8863) was available for the orthopedic doctor to predict hip survival probability.

CONCLUSIONS

The results suggest that intra-arterial infusion of auto-PBSCs prolongs femoral head survival. Age, BMI, HHS, and necrotic volume can influence the efficacy of this intervention. This study was approved by ethics committee of the trial center, number 2019-KL-075-01.

Urinary miRNAs as biomarkers for idiopathic osteonecrosis of femoral head: A multicentre study

Objectives

Urinary microRNAs (miRNAs) have shown great diagnostic and prognostic values for multiple diseases. The profile of urinary miRNAs in patients with idiopathic osteonecrosis of femoral head (ONFH) is currently unclear.

Methods

We first randomly chose ten patients with each Association Research Circulation Osseous (ARCO) stage (I, II, III and IV) and ten healthy participants from the entire cohorts for initial screening. The miRNA polymerase chain reaction (PCR) array was then performed to identify the differentially abundant miRNAs in urine of these participants. We then verified the findings in the entire cohort. Clinical features including age, gender, bone mass index (BMI), lesion size and stages were recorded. We then analysed the association between the level of urinary miRNAs and clinical features.

Results

Our data indicated that there were 13 differentially abundant miRNAs among all groups. Urinary miR-150 demonstrated the highest diagnostic value among all candidates. Urinary miR-185 and miR-133a increased by ARCO staging. The levels of urinary miR-4824 abruptly decreased after femoral head collapse (ARCO stage III and IV). Urinary miR-144 was the only marker that correlated with lesion size.

Conclusions

The levels of urinary miRNAs are valuable biomarkers for idiopathic ONFH. Given the noninvasive nature of this test, it is potentially useful for diagnosis and monitoring of idiopathic ONFH progression.

The translational potential of this article

This article gives novel methods for ONFH diagnosis and progression monitoring in a convenient and non-invasive way.

Long-term bone and lung consequences associated with hospital-acquired severe acute respiratory syndrome: a 15-year follow-up from a prospective cohort study

The most severe sequelae after rehabilitation from SARS are femoral head necrosis and pulmonary fibrosis. We performed a 15-year follow-up on the lung and bone conditions of SARS patients. We evaluated the recovery from lung damage and femoral head necrosis in an observational cohort study of SARS patients using pulmonary CT scans, hip joint MRI examinations, pulmonary function tests and hip joint function questionnaires. Eighty medical staff contracted SARS in 2003. Two patients died of SARS, and 78 were enrolled in this study from August 2003 to March 2018. Seventy-one patients completed the 15-year follow-up. The percentage of pulmonary lesions on CT scans diminished from 2003 (9.40 ± 7.83)% to 2004 (3.20 ± 4.78)% (P < 0.001) and remained stable thereafter until 2018 (4.60 ± 6.37)%. Between 2006 and 2018, the proportion of patients with interstitial changes who had improved pulmonary function was lower than that of patients without lesions, as demonstrated by the one-second ratio (FEV₁/FVC%, t = 2.21, P = 0.04) and mid-flow of maximum expiration (FEF_25%–75%, t = 2.76, P = 0.01). The volume of femoral head necrosis decreased significantly from 2003 (38.83 ± 21.01)% to 2005 (30.38 ± 20.23)% (P = 0.000 2), then declined slowly from 2005 to 2013 (28.99 ± 20.59)% and plateaued until 2018 (25.52 ± 15.51)%. Pulmonary interstitial damage and functional decline caused by SARS mostly recovered, with a greater extent of recovery within 2 years after rehabilitation. Femoral head necrosis induced by large doses of steroid pulse therapy in SARS patients was not progressive and was partially reversible.

The effect of rotational degree and routine activity on the risk of collapse in transtrochanteric rotational osteotomy for osteonecrosis of the femoral head-a finite element analysis

To explore the mechanical mechanism and provide preoperative planning basis for transtrochanteric rotational osteotomy (TRO) procedure, a joint-preserving procedure for osteonecrosis of the femoral head. Eleven TRO finite element femurs with the most common types of necrosis were analyzed under multi-loading conditions. Thereafter, we made a comprehensive evaluation by considering the anatomy characters, daily activities, and risk indicators contain necrosis expansion trend, necrotic blood supply pressure, and the risk of fracture. The risk of fracture (ROF) is the lowest when standing on feet and increases gradually during normal walking and walking upstairs and downstairs. Compared with posterior rotation, rotating forward keeps more elements at low risk. Additionally, the correlation analysis shows it has a strong negative correlation (R² = 0.834) with the average modulus of the roof. TRO finally decreased the stress and energy effectively. However, the stress and strain energy arise when rotated posteriorly less than 120°. The comprehensive evaluation observed that rotating forward 90°could reduce the total risks to 64%. TRO is an effective technique to prevent collapse. For the anterior and superior large necrosis, we recommend to rotate forward 60° to 90° (more efficient) or backward 180°. The methodology followed in this study could provide accurate and personalize preoperative planning.

Graphical Abstract

Peripheral Blood Stem Cell Therapy Does Not Improve Outcomes of Femoral Head Osteonecrosis With Cap-Shaped Separated Cartilage Defect

A combination treatment with porous tantalum rod implantation and intra-arterial infusion of peripheral blood stem cells (PBSCs) provides a promise for treating early and intermediate stages of osteonecrosis of the femoral head (ONFH). However, its clinical indications and application restrictions remain unclear. This study aims to determine the clinical, histological, and radiological outcomes of a combination treatment using mechanical support and a targeted intra-arterial infusion of PBSCs for painful ONFH with a cap-shaped separation (CSS) cartilage defect. Compared with the standard pain management (control group), this combination treatment did not improve the Harris Hip Score (HHS) at 36 months. Micro-CT and histologic analyses showed severe focal destruction in all CSS-ONFH femoral heads in both the combination and control groups. Femoral heads showed a higher percentage of bone lesions in the combination treatment group than in the control group. There was no significant difference in osteoclast number in the subchondral bone areas between the two groups. A high level of expression of inflammatory cytokines, including tumor necrosis factor-α and interleukin-1β, was detected in blood vessels around the subchondral bone in both groups. The RANKL/OPG (receptor activator of the nuclear factor-kB ligand/osteoprotegerin) ratio was also similar between the control and combination treatment groups. Our results indicate that this combination treatment is not an effective method for the treatment of patients with painful CSS-ONFH. Moreover, this combination treatment did not inhibit inflammatory osteoclastogenesis in patients with more advanced disease. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:269-276, 2020.

Acetabular Anatomical Parameters in Patients With Idiopathic Osteonecrosis of the Femoral Head

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is an increasing worldwide health problem. However, about 30% of the patients are diagnosed with idiopathic ONFH, which means no underlying etiology is identified. We hypothesized that acetabular anatomical abnormalities might be related to idiopathic ONFH.

METHODS

This retrospective, 1:2 matched, case-control study included 101 patients (136 hips) with idiopathic ONFH and 202 control subjects (404 hips) matched for age, gender, and body mass index who had no apparent radiographic hip pathologies. The anteroposterior pelvic X-rays of the patients and control subjects were used to measure the anatomical parameters including the center-edge angle, the sharp angle, the acetabular depth ratio (ADR), and the acetabular head index (AHI).

RESULTS

We found that hips with idiopathic osteonecrosis had less acetabular coverage, lower center-edge angle (28.3° vs 32.3°, P < .001), acetabular depth ratio (298.0 vs 306.4, P = .006), and acetabular head index (82.2 vs 85.8, P < .001), and higher sharp angle (39.7° vs 38.0°, P < .001), compared with the control subjects. The incidence of acetabular dysplasia was also higher in the idiopathic ONFH group than the control group.

CONCLUSION

Less acetabular coverage was found in hips with idiopathic osteonecrosis than the control subjects. Less acetabular coverage may be associated with the development of ONFH in East Asian population.

Comparison of Total Hip Arthroplasty after Two Types of Failed Hip Preserving Procedures with Primary Total Hip Arthroplasty

Objective

Porous tantalum implantation (PTI) and bone impaction grafting (BIG) through a window at the femoral head neck junction are known as two types of joint‐preserving procedures. They provide an alternative option in the treatment of osteonecrosis of the femoral head by providing strong structural support to the subchondral plate. However, when earlier joint‐preserving treatments fail, conversion to a total hip arthroplasty seems to be the final treatment of choice. This emphasizes the importance of joint‐preserving procedures that do not hinder the clinical results of a subsequent total hip arthroplasty. The results of conversion total hip arthroplasty after failed PTI and BIG are still controversial. The purpose of this study was to compare the clinical and radiological outcomes of total hip arthroplasty after failed PTI or BIG surgery with primary total hip arthroplasty.

Methods

Patients at our institution between 2010 and 2014 who underwent total hip arthroplasty after failed PTI or BIG surgery compared to primary total hip arthroplasty were retrospectively reviewed. A total of 27 patients (30 hips) who underwent total hip arthroplasty after failed PTI surgery (group I) were matched according to age, gender and BMI index with 28 patients (30 hips) who underwent total hip arthroplasty after failed BIG surgery (group II) and 30 patients (30 hips) who underwent primary total hip arthroplasty (group III). The clinical results included preoperative and postoperative Harris Hip score, surgery duration, blood loss volume and clinical complications. Radiological follow‐up results included abduction angle and anteversion angle of the acetabular cup, periprosthetic osteolysis, and prosthesis subsidence.

Results

There was no significant difference in the preoperative and postoperative Harris Hip score among the three groups at the latest follow‐up (P = 0.247). The surgery duration was longer and intra‐operative blood loss volume was higher in group I than in group II and group III (P < 0.05, respectively). There was no difference in surgery duration and blood loss volume between group II and group III (P > 0.05). There was no significant difference in radiological follow‐up results among the three groups (P > 0.05). Varying degrees of residual tantalum debris were seen on postoperative radiographs of all group I patients. There was no difference in the incidence of complications among the three groups (P > 0.05).

Conclusions

PTI group had higher blood loss volume and surgery duration than BIG group and primary total hip arthroplasty group. BIG group had no significant differences with primary total hip arthroplasty group in clinical and radiological follow‐up results. There were no significant differences between the three groups in the Harris Hip score and radiological follow‐up results.

Identification of potential miRNA biomarkers for traumatic osteonecrosis of femoral head

Traumatic osteonecrosis of femoral head (TONFH) is a common orthopedic disease caused by physical injury in hip. However, the unclear pathogenesis mechanism of TONFH and lacking of simple noninvasive early diagnosis method cause the necessity of hip replacement for most patients with TONFH. In this study, we aimed to identify circulating microRNAs (miRNAs) by integrated bioinformatics analyses as potential biomarker of TONFH. mRNA expression profiles were downloaded from the Gene Expression Omnibus database. Then we combined two miRNA screen methods: Weighted gene co-expression network analysis and fold change based differentially expressed miRNAs analysis. As a result, we identified 14 key miRNAs as potential biomarkers for TONFH. Besides, 302 target genes of these miRNAs were obtained and the miRNA-mRNA interaction network was constructed. Furthermore, the results of Kyoto Encyclopedia of Gene and Genome pathway analysis, Gene Ontology function analysis, protein-protein interaction (PPI) network analysis and PPI network module analysis showed close correlation between these 14 key miRNAs and TONFH. Then we established receiver operating characteristic curves and identified 6-miRNA signature with highly diagnosis value including miR-93-5p (area under the curve [AUC] = 0.93), miR-1324 (AUC = 0.92), miR-4666a-3p (AUC = 0.92), miR-5011-3p (AUC = 0.92), and miR-320a (AUC = 0.89), miR-185-5p (AUC = 0.89). Finally, the results of quantitative real-time polymerase chain reaction confirmed the significantly higher expression of miR-93-5p and miR-320a in the serum of patients with ONFH. These circulating miRNAs could serve as candidate early diagnosis markers and potential treatment targets of TONFH.

FSTL1 Promotes Inflammatory Reaction and Cartilage Catabolism through Interplay with NFκB Signaling Pathways in an In Vitro ONFH Model

Osteonecrosis of the femoral head (ONFH) usually occurs in young people and is closely associated with autoimmune reactions. Follistatin-like 1 (FSTL1) was recently proven to participate in several inflammation-related diseases. The role of FSTL1 in ONFH is still unclear. Serum levels of FSTL1 were not significantly different in ONFH patients and healthy individuals. In contrast, elevated expression levels of FSTL1 were observed in degraded cartilage and synovial fluid in ONFH patients and in a cultured human primary chondrocyte model treated with interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α). Suppression of FSTL1 by FSTL1-siRNA downregulated the inflammatory response mediated by IL-1β or TNF-α in cultured human chondrocytes. In a human cartilage culture model, FSTL1 promoted the production of inflammatory cytokines and cartilage degradation enzymes. The activation of NFκB signaling pathway was detected in degenerated cartilage from ONFH patients and in FSTL1-treated chondrocytes. Additionally, administration of an NFκB inhibitor (JSH-23) significantly reduced the overexpression of inflammatory cytokines and protein degradation enzymes induced by FSTL1 and maintained the level of major cartilage matrix components (aggrecan and collagen II). In summary, FSTL1 was involved in the degeneration progression of the ONFH and might provide a novel direction for treating and curing ONFH.

T1-weighted MRI images accurately represent the volume and surface of architectural mineral damage of osteonecrosis of the femoral head: Comparison with high-resolution computed tomography

The potency of magnetic resonance imaging (MRI) to measure the exact extent of osteonecrosis of the femoral head (ONFH) remains uncertain. The objective of this study was to determine if the volume of necrosis assessed with MRI accurately reflects the volume of architectural mineral alterations in osteonecrosis of the femoral head by comparison with high-resolution microfocus X-ray computed tomography (HR-μCT). Fourteen male patients aged 53 years [46.2;59.0] suffering from ONFH were prospectively enrolled to undergo preoperative MRI and ex vivo analysis using HR-μCT. The necrotic zone on T1-weighted MRI scans was defined as total necrosis (delimited by the low-signal peripheral band) or dark necrosis (low-signal lesions only). The HR-μCT scans delimited outer necrosis and inner necrosis by including or excluding the sclerotic zone. The intra-class correlation coefficient (ICC) was calculated to compare the agreement of surface areas and volumes of necrosis measurements with the two techniques. There was an overall excellent agreement between MRI dark necrosis volume and HR-μCT outer necrosis volume (ICC=0.91[0.54;0.98]) while the MRI total necrosis volume showed poor agreement with both HR-μCT delimitations of necrosis volume. For surface area, agreement between MRI dark necrosis and HR-μCT delimitations was good for inner necrosis (ICC=0.70[0.21;0.9]) and moderate for outer necrosis (ICC=0.58[0.07;0.85]). This study demonstrates that measurement of the MRI lesions provides a reliable assessment of the extent of ONFH-related architectural damage.

Increased COUP-TFII Expression Mediates the Differentiation Imbalance of Bone Marrow-Derived Mesenchymal Stem Cells in Femoral Head Osteonecrosis

Objective

Bone marrow-derived mesenchymal stem cells (BMSCs) have multilineage differentiation potential, which allows them to progress to osteogenesis, adipogenesis, and chondrogenesis. An imbalance of differentiation between osteogenesis and adipogenesis will result in pathologic conditions inside the bone. This type of imbalance is also one of the pathological findings in osteonecrosis of the femoral head (ONFH). Chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII) was previously reported to mediate the differentiation of mesenchymal stem cells. This study investigated the expression of the osteogenesis regulator Runx2, osteocalcin, the adipogenesis regulator PPARγ, and COUP-TFII in the femoral head tissue harvested from ONFH patients, and characterized the effect of COUP-TFII on the differentiation of primary BMSCs.

Methods

Thirty patients with ONFH were recruited and separated into 3 groups: the trauma-, steroid- and alcohol-induced ONFH groups (10 patients each). Bone specimens were harvested from patients who underwent hip arthroplasty, and another 10 specimens were harvested from femoral neck fracture patients as the control group. Expression of the osteogenesis regulator Runx2, osteocalcin, the adipogenesis regulator PPARγ, C/EBP-α, and COUP-TFII was analyzed by Western blotting. Primary bone marrow mesenchymal cells were harvested from ONFH cells treated with COUP-TFII RNA interference to evaluate the effect of COUP-TFII on MSCs.

Results

ONFH patients had significantly increased expression of the adipogenesis regulator PPARγ and C/EBP-α and decreased expression of the osteogenesis regulator osteocalcin. ONFH bone tissue also revealed higher COUP-TFII expression. Immunohistochemical staining displayed strong COUP-TFII immunoreactivity adjacent to osteonecrotic trabecular bone. Increased COUP-TFII expression in the bone tissue correlated with increased PPARγ and decreased osteocalcin expression. Knockdown of COUP-TFII with siRNA in BMSCs reduced adipogenesis and increased osteogenesis in mesenchymal cells.

Conclusion

Increased COUP-TFII expression mediates the imbalance of BMSC differentiation and progression to ONFH in patients. This study might reveal a new target in the treatment of ONFH.

Free vascularized iliac bone flap based on deep circumflex iliac vessels graft for the treatment of osteonecrosis of femoral head

BACKGROUND

To investigate the feasibility and clinical efficacy of free vascularized iliac bone flap based on deep iliac circumflex vessels graft for the treatment of osteonecrosis of femoral head (ONFH) in young adults.

METHODS

Eighteen patients (19 hips) undergoing ONFH were included from January 2016 to May 2017. After the debridement of the necrotic bones, the contralateral vascularized iliac bone flap was designed and harvested before grafting, in which the deep circumflex iliac vessels and the transverse branch (or ascending branch) of the lateral circumflex femoral artery and their accompanying veins were anastomosed. X-ray was obtained at 1, 3, 6, 9, and 12 months respectively for evaluation of the bone flap healing. Hip function was evaluated with Harris hip score at 18 months postoperatively.

RESULTS

None of the patients is lost to follow-up. All the hips healed well except for four complications: one patient developed superficial wound infection, one patient had subcutaneous hematoma, and two patients developed anterolateral femoral cutaneous nerve injury. X-ray films at 12 months showed improvement in 13 hips (68.4%), five hips (26.3%) were unchanged, and one femoral head collapse with conversion to total hip arthroplasty (THA) at 14 months postoperatively (5.3%). Postoperative mean Harris hip scores were significantly improved compared to the preoperative results (P < 0.05).

CONCLUSION

Free vascularized iliac bone flap based on deep circumflex iliac vessels graft is an acceptable treatment option for young adult ONFH in mid-late stage with low conversion to THA rate at short-term follow-up.

S100 Calcium Binding Protein A9 Represses Angiogenic Activity and Aggravates Osteonecrosis of the Femoral Head

Ischemic damage aggravation of femoral head collapse is a prominent pathologic feature of osteonecrosis of the femoral head (ONFH). In this regard, S100 calcium binding protein A9 (S100A9) is known to deteriorate joint integrity, however, little is understood about which role S100A9 may play in ONFH. In this study, a proteomics analysis has revealed a decrease in the serum S100A9 level in patients with ONFH upon hyperbaric oxygen therapy. Serum S100A9 levels, along with serum vascular endothelial growth factor (VEGF), soluble vascular cell adhesion molecule-1 (sVCAM-1), interleukin-6 (IL-6), and tartrate-resistant acid phosphatase 5b levels were increased in patients with ONFH, whereas serum osteocalcin levels were decreased as compared to healthy controls. Serum S100A9 levels were increased with the Ficat and Arlet stages of ONFH and correlated with the patients with a history of being on glucocorticoid medication and alcohol consumption. Osteonecrotic tissue showed hypovasculature histopathology together with weak immunostaining for vessel marker CD31 and von Willrbrand factor (vWF) as compared to femoral head fracture specimens. Thrombosed vessels, fibrotic tissue, osteocytes, and inflammatory cells displayed strong S100A9 immunoreactivity in osteonecrotic lesion. In vitro, ONFH serum and S100A9 inhibited the tube formation of vessel endothelial cells and vessel outgrowth of rat aortic rings, whereas the antibody blockade of S100A9 improved angiogenic activities. Taken together, increased S100A9 levels are relevant to the development of ONFH. S100A9 appears to provoke avascular damage, ultimately accelerating femoral head deterioration through reducing angiogenesis. This study provides insight into the molecular mechanism underlying the development of ONFH. Here, analysis also highlights that serum S100A9 is a sensitive biochemical indicator of ONFH.

Expression Profile Analysis of Differentially Expressed Circular RNAs in Steroid-Induced Osteonecrosis of the Femoral Head

Background

A growing number of studies have suggested that circular RNAs (circRNAs) serve as potential diagnostic biomarkers in many diseases. However, the role of circRNAs in steroid-induced osteonecrosis of the femoral head (SONFH) has not been reported.

Methods

Secondary sequencing was performed to profile circRNA expression in peripheral blood samples from three SONFH patients and three healthy individuals. We confirmed our preliminary findings by qRT-PCR. Bioinformatics analysis was conducted to predict their functions.

Results

The result showed 345 dysregulated circRNAs. qRT-PCR of eight selected circRNAs preliminarily confirmed the results, which were consistent with RNA sequencing. Bioinformatics analyses were performed to predict the functions of circRNAs to target the genes of miRNAs and the networks of circRNA-miRNA-mRNA interactions.

Conclusions

This study provides a new and fundamental circRNA profile of SONFH and a theoretical basis for further studies on the functions of circRNAs in SONFH.

Classification of osteonecrosis of the femoral head: Who should have surgery?

Objectives

Using a simple classification method, we aimed to estimate the collapse rate due to osteonecrosis of the femoral head (ONFH) in order to develop treatment guidelines for joint-preserving surgeries.

Methods

We retrospectively analyzed 505 hips from 310 patients (141 men, 169 women; mean age 45.5 years (sd 14.9; 15 to 86)) diagnosed with ONFH and classified them using the Japanese Investigation Committee (JIC) classification. The JIC system includes four visualized types based on the location and size of osteonecrotic lesions on weightbearing surfaces (types A, B, C1, and C2) and the stage of ONFH. The collapse rate due to ONFH was calculated using Kaplan–Meier survival analysis, with radiological collapse/arthroplasty as endpoints.

Results

Bilateral cases accounted for 390 hips, while unilateral cases accounted for 115. According to the JIC types, 21 hips were type A, 34 were type B, 173 were type C1, and 277 were type C2. At initial diagnosis, 238/505 hips (47.0%) had already collapsed. Further, the cumulative survival rate was analyzed in 212 precollapsed hips, and the two-year and five-year collapse rates were found to be 0% and 0%, 7.9% and 7.9%, 23.2% and 36.6%, and 57.8% and 84.8% for types A, B, C1, and C2, respectively.

Conclusion

Type A ONFH needs no further treatment, but precollapse type C2 ONFH warrants immediate treatment with joint-preserving surgery. Considering the high collapse rate, our study results justify the importance of early diagnosis and intervention in asymptomatic patients with type C2 ONFH.

Cite this article: Y. Kuroda, T. Tanaka, T. Miyagawa, T. Kawai, K. Goto, S. Tanaka, S. Matsuda, H. Akiyama. Classification of osteonecrosis of the femoral head: Who should have surgery?. Bone Joint Res 2019;8:451–458. DOI: 10.1302/2046-3758.810.BJR-2019-0022.R1.

Bone turnover markers may predict the progression of osteonecrosis of the femoral head in aged males

Background

Recent studies suggest that the imbalance of bone metabolism is associated with the pathogenesis of osteonecrosis of the femoral head (ONFH). However, limited data exist on the bone turnover markers (BTMs) in these patients compared with the healthy control (HC) comprehensively.

Methods

In total, 196 participants aged 29-83 [53 patients were excluded, 70 nontraumatic ONFH (mean age 57.75±12.61; mean BMI 24.10±3.04) and 73 HC (mean age 54.04±11.12; mean BMI 23.67±3.64)] were recruited in our cross-sectional study. Osteocalcin (OC), t-P1NP (N-terminal procollagen type 1 extension pro-peptide), β-CTx (beta-isomerized type I collagen C-telopeptide breakdown products), 25-hydroxy-cholecalciferol, and parathormone (PTH) were measured using automated analyser.

Results

In comparison to controls, nontraumatic ONFH patients have lower 25(OH)D levels and higher levels of t-P1NP, β-CTx and OC (P<0.01). But there was no significant difference in PTH levels between these two groups. Logistic regression analysis revealed that low 25(OH)D and high t-P1NP were significantly associated with nontraumatic ONFH. ROC curve analysis showed the highest AUC for t-P1NP+25(OH)D model [t-P1NP+25(OH)D: 0.702, 95% CI: 0.620-0.776; t-P1NP: 0.621, 95% CI: 0.536-0.701; 25(OH)D: 0.678, 95% CI: 0.594-0.753]. With regard to the cutoff values calculated from the ROC curves, t-P1NP+25(OH)D model showed 64.29% sensitivity and 73.97% specificity. The deficiency of 25(OH)D occurred at all phases, and other BTMs were in a high rate during different phases according to the ARCO classification.

Conclusions

Both 25(OH)D deficiency and high t-P1NP were independent risk factors for nontraumatic ONFH. Our results suggest that BTMs, t-P1NP+25(OH)D model (t-P1NP ≥54.82 ng/mL and 25(OH)D ≤21.86 ng/mL), may facilitate to diagnose nontraumatic ONFH in aged male patients.

Mid-term outcomes of arthroscopic-assisted Core decompression of Precollapse osteonecrosis of femoral head-minimum of 5 year follow-up

Background

Osteonecrosis of the femoral head (ONFH) is a progressive disease that leads to collapse and the development of secondary arthritis. The preferred management of ONFH remains controversial. Arthroscopic-assisted management of ONFH is a new and evolving approach for hip preservation. We hypothesis that arthroscopy is able to improve ONFH outcomes by achieving accurate and minimally invasive decompression while successfully addressing concomitant intraarticular pathologies resulting in reliable mid-term outcomes.

Methods

This was a retrospective cohort analysis. All patients had atraumatic ONFH with a precollapse lesion and a minimum follow-up of 5 years.

Results

A total cohort of 11 hips (8 patients) was identified. The mean patient follow-up was 7 years ±1.48 years (range, 64—118 months). The Ficat-Alret classification found on preoperative imaging was Stage I—3 (27.2%), IIa—4 (36.4%), and IIb—4 (36.4%) hips. Four (36.4%) hips experienced mechanical issues, including locking, catching, and buckling. The most common concomitant pathology addressed at the time of arthroscopy, was labral repair/debridement—8 (73%), followed by microfracture—7 (64%). At final follow-up, 6 hips (54.5%) had not converted to THA. Upon further stratification, Stage I—100%, Stage IIa—75%, for a combined 87%, had not converted to THA, in contrast, 100% of hips categorized as Stage IIb had converted to THA. Ficat-Alret staging, especially Stage IIb, was significantly associated with conversion to THA. (p-value = 0.015) There were 0% major or minor complications.

Conclusions

To our knowledge, this is the longest reported follow-up of arthroscopic-assisted management of ONFH. Arthroscopic-assisted management is a promising surgical approach that provides safe, accurate, and minimally invasive decompression, resulting in reliable results with an acceptable conversion rate to THA.

Level of evidence

Level IV, Case Series.

[Minimally invasive treatment for osteonecrosis of the femoral head in ARCO stage and with bioceramic system]

Objective

To perfect the theory system of minimally invasive treatment for osteonecrosis of the femoral head (ONFH) with β tricalcium phosphate (β-TCP) bioceramic system and evaluate the effectiveness.

Methods

Eighteen New Zealand white rabbits aged 7-8 months were used to establish an animal model to verify the vascularization of porous β-TCP bioceramic rods. Micro-CT based three-dimensional reconstruction and fluorescence imaging were used to display the new blood vessels at 4, 8, and 12 weeks after operation. The inserting depth, number and diameter of vessels in the encapsulated area were analyzed. Nine pig femoral specimens were randomly divided into 3 groups ( n=3): group A was normal femur; group B had cavity (core decompression channel+spherical bone defect in femoral head); in group C, mixed bioceramic granules were implanted to fill the defect in femoral head, and porous β-TCP bioceramic rod was implanted into decompression channel. The stiffness and yield load of specimens were analyzed by biomechanical test. A multicenter retrospective study was conducted to analyze 200 patients (232 hips) with femoral head necrosis treated with bioceramic system in 7 hospitals in China between January 2012 and July 2018. There were 145 males and 55 females, with an average age of 42 years (range, 17-76 years). According to the Association Research Circulation Osseous (ARCO) stage, 150 hips were in stage Ⅱ and 82 hips in stage Ⅲ. Postoperative imaging assessment was carried out regularly, and hip function was evaluated by Harris score. The effectiveness of ARCO stage Ⅱ and Ⅲ was also compared.

Results

Animal experiments showed that blood vessels could grow into the encapsulated area and penetrate it at 12 weeks. The inserting depth, number and diameter of blood vessels in the encapsulated area gradually increased, and there was significant difference between different time points ( P<0.05). Biomechanical tests showed that the stiffness and yield load of specimens in groups B and C were significantly lower than those in group A, while the yield load in group B were significantly lower than that in group C ( P<0.05). The stiffness in group C was restored to 41.52%±3.96% in group A, and the yield load was restored to 46.14%±7.85%. Clinical study showed that 200 patients were followed up 6-73 months, with an average of 22.7 months. At last follow-up, 12 patients (16 hips) underwent total hip arthroplasty, and the hip survival rate was 93.10%. According to the imaging evaluation, 184 hips (79.31%) were stable and 48 (20.69%) were worse. Harris score (79.3±17.3) was significantly higher than that before operation (57.3±12.0) ( t=18.600, P=0.000). The excellent rate of hip function was 64.22% (149/232). The survival rate of hip joint, imaging score and Harris score of patients in ARCO stage Ⅱ were better than those in ARCO stage Ⅲ ( P<0.05).

Conclusion

β-TCP bioceramic system can guide the abundant blood supply of greater trochanter and femoral neck to the femoral head to promote repair; it can partly restore the mechanical properties of the femoral head and neck in the early stage, providing a new minimally invasive hip-preserving method for patients with ONFH, especially for those in early stage.

Hypoxia-inducible factor (HIF): how to improve osseointegration in hip arthroplasty secondary to avascular necrosis in sickle cell disease

Many studies in the literature have been carried out to evaluate the various cellular and molecular processes involved in osteogenesis.

Angiogenesis and bone formation work closely together in this group of disorders. Hypoxia-inducible factor (HIF) which is stimulated in tissue hypoxia triggers a cascade of molecular processes that helps manage this physiological deficiency.

However, there still remains a paucity of knowledge with regard to how sickle cell bone pathology, in particular avascular necrosis, could be altered when it comes to osseointegration at the molecular level.

Hypoxia-inducible factor has been identified as key in mediating how cells adapt to molecular oxygen levels.

The aim of this review is to further elucidate the physiology of hypoxia-inducible factor with its various pathways and to establish what role this factor could play in altering the disease pathophysiology of avascular necrosis caused by sickle cell disease and in improving osseointegration.

This review article also seeks to propose certain research methodology frameworks in exploring how osseointegration could be improved in sickle cell disease patients with total hip replacements and how it could eventually reduce their already increased risk of undergoing revision surgery.

Cite this article: EFORT Open Rev 2019;4:567-575. DOI: 10.1302/2058-5241.4.180030

How to evaluate the clinical outcome of joint-preserving treatment for osteonecrosis of the femoral head: development of a core outcome set

Background

This study aimed to develop a core outcome set (COS) for clinical trials of joint-preserving treatment for osteonecrosis of the femoral head (ONFH), that is, to define a minimal set of outcomes that should be reported in such trials.

Methods

A mixed research method was adopted in this study. First, clinical trials of hip preservation therapy were systematically researched and analyzed. Second, a three-round Delphi survey involving both doctors and patients was carried out to obtain the core outcome indicators. Round 1 was a modified Delphi questionnaire for doctors and patients to determine which outcomes are important to these stakeholders, round 2 determined what clinical evaluation core outcomes should be included for the joint-preserving treatment of ONFH, and round 3 determined how core outcomes should be measured. Finally, a consensus meeting was held to discuss and vote on the established COS.

Results

The results of the systematic review showed that 42 outcome indicators were classified according to common signs and symptoms, quality of life, long-term outcomes, radiological evaluation, blood biochemistry, and indexes of safety. The three rounds of Delphi surveys completed the selection of indicators for the COS and the determination of the corresponding measurements.

A total of 73 orthopedic doctors and 103 patients participated in round 1, and the top 10 indicators selected were basically the same. In round 2, 32 experts identified the following indicators: pain, range of motion (ROM) of hip flexion, walking distance, and stable rating of X-ray images. In round 3, 35 experts defined the measurement of each indicator. Finally, the consensus meeting identified the four indicators aforementioned that constituted the COS.

The scores for pain, ROM of hip flexion, and walking distance are from 0 to 10; 0 represents the best scores, while 10 represents the most serious impairment. The stable rating of X-ray images is determined by the morphology of the femoral head and the change in the density of the necrotic area.

Conclusions

We established a COS for hip-preserving treatment of ONFH that includes four indicators: pain, ROM of hip flexion, walking distance, and stable rating of X-ray images.

Serum levels of carotenoids in patients with osteonecrosis of the femoral head are lower than in healthy, community-living people

PURPOSE

Oxidative stress is closely associated with the pathogenesis of nontraumatic osteonecrosis of the femoral head (ONFH). This study aimed to determine whether the serum levels of antioxidant nutrients were decreased in patients with ONFH.

METHODS

We analyzed the serum levels of antioxidant nutrients in 39 patients with ONFH (ONFH group) and 78 age- and gender-matched healthy people (control group) who voluntarily participated in the Yakumo study, which is a comprehensive health examination program. We measured and compared the serum levels of α-tocopherol (vitamin E) and total carotenoids, including zeaxanthin/lutein, β-cryptoxanthin, lycopene, α-carotene, and β-carotene, in the ONFH and control groups using high-performance liquid chromatography.

RESULTS

The mean serum levels of total carotenoids were significantly lower in the ONFH group than in the control group (2.36 ± 1.26 and 3.79 ± 2.36 µmol/l, respectively, p < 0.001). However, no significant difference was found in α-tocopherol between the two groups (26.37 ± 6.90 µmol/l in the ONFH group and 26.24 ± 6.28 µmol/l in the control group, p = 0.920). Among each carotenoid, the serum levels of zeaxanthin/lutein, lycopene, and β-carotene were significantly lower in the ONFH group than in the control group ( p < 0.001).

CONCLUSIONS

The serum levels of carotenoids were lower in patients with ONFH than in healthy, community-living people. This result suggests that carotenoids may be related to the pathogenesis of ONFH.

Long-Term Survivorship of Total Hip Arthroplasty with Highly Cross-Linked Polyethylene for Osteonecrosis

BACKGROUND

Osteonecrosis of the hip is the underlying etiology for 3% to 12% of total hip arthroplasties (THAs). Compared with patients who undergo THA because of osteoarthritis, those who do so because of osteonecrosis typically are younger, have a greater number of underlying diagnoses, and have inferior clinical outcomes and implant survivorship. The purpose of this study was to compare the long-term implant survivorship (median follow-up, 10 years), functional outcomes, and radiographic results of contemporary THAs with a highly cross-linked polyethylene (HXLPE) liner between patients with osteonecrosis and those with osteoarthritis.

METHODS

All patients who underwent primary THA with an HXLPE liner from 1999 to 2007 were identified from our institutional total joint registry. Patients with a primary diagnosis of osteonecrosis were matched 1:1, on the basis of age, sex, and body mass index (BMI), to patients with a diagnosis of osteoarthritis. This resulted in 461 hips in 413 patients with osteonecrosis matched to 461 hips in 427 patients with osteoarthritis (mean age, 59 years; 47% female; and mean BMI, 29 kg/m). Long-term implant survivorship, patient-reported outcomes, and radiographic findings were compared. In addition, a subgroup analysis of the osteonecrosis group was performed to see whether certain underlying etiologies portended poor outcomes. The median follow-up was 10 years.

RESULTS

The 15-year cumulative rates of revision were 6.6% and 4.5% in the osteonecrosis and osteoarthritis groups, respectively (hazard ratio [HR] = 1.8, p = 0.09). The 15-year cumulative rates of any reoperation were 10.5% and 6.4% in the osteonecrosis and osteoarthritis groups, respectively (HR = 2.2, p = 0.008). There were no radiographic signs of component loosening or osteolysis in the entire cohort. Despite a lower median preoperative Harris hip score (HHS) for patients with osteonecrosis, both groups had marked improvements in their scores, which were similar at all time points after surgery. The cumulative rate of reoperations at 15 years was 0% for hips with radiation-induced osteonecrosis, 6.3% for those with alcohol-induced osteonecrosis, 9.0% for those with posttraumatic osteonecrosis, 12.1% for those with steroid-induced osteonecrosis, and 25% for those with idiopathic osteonecrosis.

CONCLUSIONS

Contemporary THA with an HXLPE liner offers excellent long-term implant survivorship and functional outcomes for patients with osteonecrosis; however, the risk of a reoperation is higher when compared with patients with osteoarthritis.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.