Management of non-traumatic avascular necrosis of the femoral head-a comparative analysis of the outcome of multiple small diameter drilling and core decompression with fibular grafting

Prognostic factors in the management of osteonecrosis of the femoral head: A systematic review

BACKGROUND

Several hip preserving techniques have been described for the management of osteonecrosis of the femoral head (ONFH). This systematic review identified prognostic factors in the treatment of ONFH that are associated with treatment failure and conversion to total hip arthroplasty (THA).

MATERIAL AND METHODS

This study followed the PRISMA guidelines. The literature search was conducted in November 2021. All clinical trials comparing two or more treatments for femoral head osteonecrosis were accessed. A multivariate analysis was performed to investigate the association between baseline characteristics and the surgical outcome. A multiple linear model regression analysis through the Pearson Product-Moment Correlation Coefficient (r) was used.

RESULTS

Data from 88 articles (6112 procedures) were retrieved. Female gender was associated with increased time to THA (P = 0.03) and reduced rate of THA (P = 0.03). Longer symptom duration before treatment was associated with shorter time to failure (P = 0.03). Increased pre-treatment VAS was associated with reduced time to failure (P = 0.03) and time to THA (P = 0.04). Reduced pre-treatment hip function was associated with increased rate of THA (P = 0.02) and failure (P = 0.005). Patient age and BMI, aetiology, time from surgery to full weight bearing and the side did not show evidence of a statistically significant association with the surgical outcome.

CONCLUSION

Male gender, longer symptom duration before treatment, higher VAS scores, and lower HHS scores were negative prognostic factors after treatment for osteonecrosis of the femoral head.

Comparison of current treatment strategy for osteonecrosis of the femoral head from the perspective of cell therapy

Aims: The purpose of our study is to compare the effects of core decompression (CD) and bone grafting (BG) on osteonecrosis of the femoral head (ONFH). And evaluate the efficacy of CD based on cell therapy to provide guidance for the dose and number of cells. Methods: We searched PubMed, Embase, and the Cochrane Library between 2012 and 2022, with keywords including "osteonecrosis of the femoral head", "core decompression" and "bone grafting". We selected comparative studies of CD and BG, and the comparison of CD combined with bone marrow (BM) transplantation and CD alone. Changes in hip pain were assessed by VAS, hip function were assessed by HHS and WOMAC, and THA conversion rate was used as an evaluation tool for femoral head collapse. From these three aspects, the dose of bone marrow and the number of cells transplantation were subgroup analyzed. Results: Eleven studies were used to compare the efficacy of CD and BG. There was no significant difference in HHS, and the THA conversion rate of BG was significantly lower than that of CD. Thirteen CD studies based on cell therapy were included in the meta-analysis. Bone marrow aspiration concentrate (BMAC) can significantly improve VAS (mean difference (MD), 10.15; 95% confidence intervals (CI) 7.35 to 12.96, p < 0.00001) and reduce THA conversion rate (odds ratio (OR), 2.38; 95% CI 1.26 to 4.47, p = 0.007). Medium dose bone marrow fluid has a lower p-value in THA conversion rate. The p values of bone marrow mononuclear cells (BMMC) of 10⁹ magnitude in VAS score were lower. Conclusion: In general, there is no consensus on the use of BG in the treatment of ONFH. The enhancement of cell-based CD procedure shows promising results. Using 20 mL BMAC and 10⁹ magnitude BMMC is likely to achieve better results.

A modified surgical method for the treatment of ONFH: quadratus femoris muscle pedicle bone grafting with preservation of the posterior superior retinacular artery

BACKGROUND

Osteonecrosis of the femoral head (ONFH) can lead to pain and loss of function of the hip joint, which places a great burden on patients and society. Surgery is the main treatment for osteonecrosis of the femoral head, and quadratus femoris muscle pedicle bone grafting has a definite therapeutic effect as one method of surgery for the treatment of ONFH. However, the posterior superior retinacular artery is often injured during quadratus femoris muscle pedicle bone graft surgery. There is evidence that this artery is extremely important to the femoral head, as injury to this artery will seriously affect the blood supply of the femoral head. Therefore, this situation restricts the clinical application of quadratus femoris muscle pedicle bone grafts. We aimed to explore a new surgical method of quadratus femoris muscle pedicle bone grafting that can preserve the integrity of the posterior superior retinacular artery.

METHODS

We modified the traditional quadratus femoris muscle pedicle bone graft and preserved the integrity of the posterior superior retinacular artery. To explore the safety and feasibility of the operation, we simulated the operation on 6 fresh frozen cadavers (12 hips) and measured the related data. We also tried this modified surgical method in the clinic and collected detailed data from the patients.

RESULTS

By simulating the modified quadratus femoris muscle pedicle bone graft on the hip joints of fresh frozen cadavers, we found that the posterior superior retinacular artery existed in all cadaver specimens and that the sources may be different (MFCA or IGA). In the modified operation, the joint capsule did not need to be cut during the operation; therefore, the integrity of the posterior superior retinacular artery was preserved. The quadratus femoris muscle was exposed via the posterior approach of the hip joint, and then the quadratus femoris muscle pedicle bone flap was chiseled. After the pedicle of the quadratus femoris muscle was loosened properly, the migration distance of the quadratus femoris muscle pedicle bone flap reached 5.89 ± 0.45 (χ ± s) cm. The bone flap was trimmed properly and placed on one side. Next, we drilled a bone tunnel from the external intertrochanteric aspect of the capsule of the hip joint, and the bone tunnel broke through the sclerosing zone and proceeded straight to the necrotic area of the femoral head. Next, the necrotic bone was removed with a ring saw and arc bone knife, autogenous bone or allogeneic bone was filled into the bone groove according to the situation, and the cancellous bone in the bone groove was tamped by percussion. Then, the bone flap was inserted into the bone groove, and appropriate pressurization was performed. The depth of the bone groove was determined by the location of ONFH. We found that the furthest distance between the bone groove and the femoral head was 4.76 ± 0.07 (χ ± s) cm and that the length of the bone flap was (4.91 ± 0.23) (χ ± s) cm. This means that when the depth of the bone groove reached the area of ONFH, the quadratus femoris muscle pedicle bone flap had a sufficient length and migration distance to be embedded in the area of ONFH and firmly fixed, and the quadratus femoris did not have much tension. The closest distance between the posterior superior retinacular artery and the bone groove was (1.11 ± 0.96) (χ ± s) cm. When the bone groove was created in this area, the edge of the bone groove had a safe distance of at least 1 cm from the posterior superior retinacular artery of the femoral head. We attempted to implement this modified operation clinically. During the procedure, the quadratus femoris muscle pedicle bone flap was embedded into the drilled bone groove and fixed with a magnesium nail. There was no sliding of the bone flap after the operation, and the posterior superior retinacular artery was intact. We followed the patient for 3 months and found that the patient recovered well with no weight-bearing by the affected limb. The duration of the modified operation was shorter than that of the traditional quadratus femoris muscle pedicle bone graft, the amount of bleeding was significantly reduced, the postoperative pain was lessened, and no special discomfort was reported. Postoperative imaging examination showed that the collapse of the femoral head had been partially corrected and that the bone flap had gradually fused with the surrounding bone.

CONCLUSIONS

Through this experimental study, we confirmed the feasibility of the modified method for quadratus femoris muscle pedicle bone grafting with preservation of the posterior superior retinacular artery. This modified operation not only retains the integrity of the posterior superior retinacular artery of the femoral head but also reduces the difficulty of the operation and shortens the surgical time, which is of great clinical significance.

Minimally Invasive Necrotic Bone Washing Improves Bone Healing After Femoral Head Ischemic Osteonecrosis: An Experimental Investigation in Immature Pigs

BACKGROUND

Ischemic osteonecrosis of the femoral head produces necrotic cell debris and inflammatory molecules in the marrow space, which elicit a chronic inflammatory repair response. The purpose of this study was to determine the effects of flushing out the necrotic cell debris and inflammatory proteins on bone repair in a piglet model of ischemic osteonecrosis.

METHODS

Osteonecrosis of the femoral head of the right hindlimb was induced in 12 piglets by tying a ligature tightly around the femoral neck. One week after the surgery, 6 animals were treated with a percutaneous 3-needle bone washing procedure and non-weight-bearing (NWB) of the right hindlimb (wash group). The total saline solution wash volume was 450 mL per femoral head. Serial wash solutions were collected and analyzed. The remaining 6 animals were treated with NWB only (NWB group). At 8 weeks after the surgery, the femoral heads were assessed using radiography, micro-computed tomography (micro-CT), and histological analysis. In addition, we compared the results for these piglets with our published results for 6 piglets treated with multiple epiphyseal drilling (MED) plus NWB without bone washing (MED group).

RESULTS

Necrotic cells and inflammatory proteins were present in the bone wash solution collected 1 week after ischemia induction. The protein and triglyceride concentrations decreased significantly with subsequent washing (p < 0.005). At 8 weeks after ischemia induction, the wash group had a significantly higher bone volume than the MED or NWB group (p < 0.0001). Histological bone-formation measures were also significantly increased in the wash group compared with the MED group (p = 0.002) or NWB group (p < 0.0001) while macrophage numbers were significantly decreased in the wash group.

CONCLUSIONS

The percutaneous 3-needle procedure flushed out cell debris and inflammatory proteins from the necrotic femoral heads, decreased osteoclasts and macrophages, and increased bone formation following induction of ischemic osteonecrosis.

CLINICAL RELEVANCE

We believe that this is the first study to investigate the concept of washing out the necrotic femoral head to improve bone healing. The minimally invasive procedure may be useful to improve the necrotic bone environment and bone repair following ischemic osteonecrosis.

Comparison of cell therapy and other novel adjunctive therapies combined with core decompression for the treatment of osteonecrosis of the femoral head : a systematic review and meta-analysis of 20 studies

Aims

The value of core decompression (CD) in the treatment of osteonecrosis of the femoral head (ONFH) remains controversial. We conducted a systematic review and meta-analysis to evaluate whether CD combined with other treatments could improve the clinical and radiological outcomes of ONFH patients compared with CD alone.

Methods

We searched the PubMed, Embase, Web of Science, and Cochrane Library databases until June 2020. All randomized controlled trials (RCTs) and clinical controlled trials (CCTs) comparing CD alone and CD combined with other measures (CD + cell therapy, CD + bone grafting, CD + porous tantalum rod, etc.) for the treatment of ONFH were considered eligible for inclusion. The primary outcomes of interest were Harris Hip Score (HHS), ONFH stage progression, structural failure (collapse) of the femoral head, and conversion to total hip arthroplasty (THA). The pooled data were analyzed using Review Manager 5.3 software.

Results

A total of 20 studies with 2,123 hips were included (CD alone = 768, CD combined with other treatments = 1,355). The combination of CD with other therapeutic interventions resulted in a higher HHS (mean difference (MD) = 6.46, 95% confidence interval (CI) = 2.10 to 10.83, p = 0.004) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (MD = −10.92, 95% CI = -21.41 to -4.03, p = 0.040) and a lower visual analogue scale (VAS) score (MD = −0.99, 95% CI = -1.56 to -0.42, p < 0.001) than CD alone. For the rates of disease stage progression, 91 (20%) progressed in the intervention group compared to 146 (36%) in the control group (odds ratio (OR) = 0.32, 95% CI = 0.16 to 0.64, p = 0.001). In addition, the intervention group had a more significant advantage in delaying femoral head progression to the collapsed stage (OR = 0.32, 95% CI = 0.17 to 0.61, p < 0.001) and reducing the odds of conversion to THA (OR = 0.35, 95% CI = 0.23 to 0.55, p < 0.001) compared to the control group. There were no serious adverse events in either group. Subgroup analysis showed that the addition of cell therapy significantly improved clinical and radiological outcomes compared to CD alone, and this approach appeared to be more effective than other therapies, particularly in precollapse (stage I to II) ONFH patients.

Conclusion

There was marked heterogeneity in the studies. There is a trend towards improved clinical outcomes with the addition of stem cell therapy to CD.

Cite this article: Bone Joint Res 2021;10(7):445–458.

Relationship between hip joint medial space ratio and collapse of femoral head in non-traumatic osteonecrosis: a retrospective study

To retrospectively analyze the medial space ratio (MSR) of the hip joint to evaluate its efficacy in predicting osteonecrosis of femoral head (ONFH)-induced collapse and its impacts on the mechanical environment of necrotic femoral head. In this retrospective analysis of traditional Chinese medicine, non-traumatic ONFH (NONFH) patients from January 2008 to December 2013 were selected. The patients were divided into collapse group and non-collapse group based on whether the femoral head collapsed. The anatomical parameters including center–edge (CE) angle, sharp angle, acetabular depth ratio and MSR were evaluated. Receiver operating characteristic curves were estimated to evaluate the sensitivity and specificity of MSR and CE angle in collapse prediction. The results showed that 135 patients (151 hips) were included in this study. The differences in CE angle and MSR between collapse group and non-collapse group were statistically significant. The mean survival time of the hips of patients with MSR &lt;20.35 was greater (P &lt; 0.001) than that of patients with MSR &gt;20.35. The ONFH patients with MSR &gt;20.35 were prone to stress concentration. We could conclude that the hip joint MSR and CE angle strongly correlated with the collapse of NONFH. The specificity of MSR is higher than that of CE angle. When MSR is &gt;20.35, the collapse rate of ONFH will increase significantly.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

TRIAL REGISTRATION

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

Failure and progression to total hip arthroplasty among the treatments for femoral head osteonecrosis: a Bayesian network meta-analysis

INTRODUCTION

Osteonecrosis of the femoral head (ONFH) often leads to secondary osteoarthritis and total hip arthroplasty.

SOURCE OF DATA

Recent published literatures.

AREAS OF AGREEMENT

There has been increasing focus on the early intervention in ONFH patients to preserve the native hip articulation, reduce pain and improve function.

AREAS OF CONTROVERSY

Efficacy of surgical strategies for ONFH is debated. Several clinical studies showed controversial results, and the best treatment has not yet been clarified.

GROWING POINTS

To provide an overview over current treatment options for ONFH compares their failure rates and conversion to total hip arthroplasty (THA) rates.

AREAS TIMELY FOR DEVELOPING RESEARCH

Core decompression (CD) augmented with autologous bone grafting plus the implantation of bone marrow concentrate can decrease the rate of failure and progression to THA rates compared to CD alone.

Does augmented core decompression decrease the rate of collapse and improve survival of femoral head avascular necrosis? Case-control study comparing 184 augmented core decompressions to 79 standard core decompressions with a minimum 2 years' follow-up

INTRODUCTION

Avascular necrosis of the femoral head often progresses to femoral head collapse if not treated. Conservative treatment yields highly variable results and is not standardised, mainly because it is typically evaluated in small patient populations. This led us to conduct a large retrospective comparative study with the goals of 1) analysing survival and functional outcomes, 2) looking for differences in survival between core decompression techniques (standard versus augmented), and 3) studying the risk factors for femoral head collapse and revision by arthroplasty.

HYPOTHESIS

Core decompression limits the number of patients who suffer femoral head collapse requiring arthroplasty at 2 years' follow-up.

METHODS

This multicentre, comparative, retrospective study analysed 330 patient records (1975-2016) where at least 2 years' follow-up was available. Sixty-two patients were excluded from the analysis: 5 had a stage III with collapse, 5 were lost to follow-up, 2 died within 24 months of the procedure and 50 had incomplete data. The study included 263 patients with a mean age of 42 years (15.7-70). In the Ficat classification, there were 51 cases of stage I necrosis, 186 cases of stage II and 22 cases of stage II with crescent sign (transition stage). The Kerboull angle on radiographs was between 5° and 20° in 40 patients, between 20° and 40° in 107 patients, between 40° and 60° in 52 patients and more than 60° in 29 patients. A standard core decompression was done in 79 patients and an augmented one in 184 patients. The more severe AVN cases (stage II) were more likely to be treated by augmented CD (160/184 patients, 87%) than by standard CD (48/79 patients, 61%) (p<0.001).

RESULTS

In the 263 patients, the overall survival (no arthroplasty at 2 years) was 73% (196/263). At 2 years, the survival rate (without arthroplasty) was 71% (56/79) in the standard CD group versus 76% (140/184) in the augmented CD group. This difference was significant when adjusted for Ficat stage and Kerboull angle [HR=0.457, 95% CI (0.247-0.844) (p=0.012)]. When the survival data was adjusted to the Ficat stage, augmented CD was better than standard CD with 10-year survival of 58.1% vs. 57.9% (p=0.0082). More than 30% necrosis volume increased the risk of failure [HR=3.291 95%CI (1.494-7.248) (p=0.0031)]. Also, a Kerboull angle above 60° increased the risk of failure [HR=3.148 95%CI (1.346-7.5) (p=0.0083)].

CONCLUSION

After 2 years, CD for non-collapsed femoral head AVN prevents collapse and revision to arthroplasty in 73% of cases (196/268). Augmented CD improves the 2-year survival and the long-term survival after adjusting for preoperative characteristics (Kerboullangle and Ficat stage). The risk of collapse and need for arthroplasty is greater in patients with 30% necrosis volume on MRI and Kerboull angle above 60°.

LEVEL OF EVIDENCE

III; retrospective case-control study.

What are the outcomes of core decompression without augmentation in patients with nontraumatic osteonecrosis of the femoral head?

Purpose

Core decompression (CD) of the femoral head is performed to preserve the hip in avascular necrosis (AVN). The outcome following this procedure differs based on the medical centre and the technique. Also, the time to total hip replacement (THR) and the percentage of patients subsequently undergoing a THR are controversial.

Methods

A systematic review was performed following PRISMA guidelines. The search included CENTRAL, MEDLINE, EMBASE, Scopus, AMED and Web of Science Core Collection databases. Studies reporting the outcome of CD for AVN were assessed. Studies using additional implants, vascularized grafts or any type of augmentation were excluded. Quality assessment was performed using the Joanna Briggs Institute Critical Appraisal Checklist (JBI CAC) tool.

Trial registration

International prospective register of systematic reviews (PROSPERO) - CRD42018100596.

Results

A total of 49 studies describing 2540 hips were included. The mean weighted follow-up time was 75.1 months and the mean age at surgery was 39 years. Twenty-four of 37 studies reported improvement in all outcome scores, whilst 9/37 studies report only partial improvement post-operatively. Four studies (4/37) described poor clinical outcomes following intervention. Data was pooled from 20 studies, including 1134 hips with a weighted mean follow-up of 56 months. The percentage of hips undergoing THR averaged 38%. The time to THR had a weighted mean of 26 months after CD.

Conclusion

Pooled results from 1134 hips and of these nearly 80% with early stage of osteonecrosis, showed that approximately 38% of patients underwent a total hip replacement at an average of 26 months following core decompression without augmentation.

Electronic supplementary material

The online version of this article (10.1007/s00264-020-04790-9) contains supplementary material, which is available to authorized users.

Study on the outcome of patients with aseptic femoral head necrosis treated with percutaneous multiple small-diameter drilling core decompression: a retrospective cohort study based on magnetic resonance imaging and equivalent sphere model analysis

Background

Aseptic necrosis of the femoral head (ANFH) has a high incidence in the community and causes substantial problems with health as well as economic and social stress. Core decompression is the most commonly used treatment for early ANFH. Although many studies have reported on the efficacy of femoral head core decompression surgery for ANFH, there are still some shortcomings in assessing the severity of femoral head necrosis, the location distribution, and changes in necrotic lesions before and after surgery. Magnetic resonance imaging (MRI) and equivalent sphere model analysis were used to further clarify the clinical efficacy of percutaneous multiple small-diameter drilling core decompression in patients with ANFH.

Methods

From July 2013 to November 2016, 24 patients (32 cases of the hip joint) with ANFH who underwent percutaneous multiple small-diameter drilling core decompression were selected, and a retrospective analysis was conducted. MRI as well as VAS, OHS-C, and HHS scores were used to evaluate joint function in all patients before and 6, 12, and 24 months after the operation.

Results

Twenty-four months after the operation, 10 hips were amputated. The survival rates of alcoholic femoral head necrosis (AFNH), idiopathic femoral head necrosis (IFHN), and steroid-induced femoral head necrosis (SIFHN) patients at 24 months were 100%, 85.7% (− 2 hips), and 0.0% (− 8 hips), respectively. The MRI and equivalent sphere analysis results revealed that the anterior superior medial quadrant was the area most prone to osteonecrosis, and the posterior superior medial quadrant was the area second most prone to necrosis. After the operation, the average percentage of the AFHN necrosis area in the total volume of the femoral head decreased from 14.5 to 10.3%, and the average percentage of the IFHN necrosis area decreased from 16.3 to 9.2%; however, the average percentage of the necrosis area for SIFHN increased from 30.4 to 33.1%.

Conclusion

Percutaneous multiple small-diameter drilling core decompression significantly reduced the lesion volume for AFHN and IFHN, but the effect on SIFHN was not good.

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.

A Comparison of Transphyseal Neck-Head Tunneling and Multiple Epiphyseal Drilling on Femoral Head Healing Following Ischemic Osteonecrosis: An Experimental Investigation in Immature Pigs

BACKGROUND

Two operative procedures are currently advocated to stimulate the necrotic femoral head healing in children with Legg-Calve-Perthes disease: transphyseal neck-head tunneling (TNHT) and multiple epiphyseal drilling (MED). The purpose of this study was to compare the bone healing and physeal function after treatment with TNHT or MED in a piglet model of ischemic osteonecrosis.

METHODS

Eighteen piglets were induced with osteonecrosis by surgically placing a ligature tightly around the right femoral neck. One week later, the piglets were assigned to 1 of 3 treatment groups (n=6/group): (1) local nonweight bearing only (NWB), (2) TNHT plus NWB, or (3) MED plus NWB. The unoperated left femoral heads were used as normal controls. The animals were euthanized at 8 weeks after osteonecrosis induction. Histologic, histomorphometric, radiographic, microcomputed tomography (CT), and calcein-labeling assessments were performed. Statistical analysis included a 1-way ANOVA.

RESULTS

Micro-CT analyses showed higher femoral head bone volume in the MED group compared with the TNHT and the NWB groups (P<0.01). The MED group had a higher mean trabecular number (P<0.001) and new bone formation (P=0.001) based on calcein-labeling parameters compared with the TNHT and the NWB groups. In addition, the osteoclast number per bone surface was lower in the MED group compared with the NWB group (P=0.001). Histologic and micro-CT assessments of the proximal femoral physis revealed a larger physeal disruption at the site of physeal drilling in the TNHT group compared with the MED group. However, no significant differences in physeal elongation (P=0.61) and femoral neck length (P=0.31) were observed between the treatment groups.

CONCLUSIONS

MED produced a higher bone volume and stimulated greater bone formation than the TNHT or the NWB alone. Both procedures did not produce a significant physeal growth disturbance during the study period.

CLINICAL RELEVANCE

This preclinical study provides evidence that MED produces more favorable bone healing than the TNHT in a large animal model of Legg-Calve-Perthes disease.

Joint-preserving procedures for osteonecrosis of the femoral head

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

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

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

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

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

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.

Effects of transplantation of FGF-2-transfected MSCs and XACB on TNF-α expression with avascular necrosis of the femoral head in rabbits

Objective: The present study aimed to investigate the effect of the transplantation of basic fibroblast growth factor (FGF-2) gene-transfected mesenchymal stem cells (MSCs) and xenogeneic antigen-cancellous bone (XACB) on tumor necrosis factor-α (TNF-α) expression with avascular necrosis of the femoral head (ANFH) in rabbits. Methods: The models of steroid-induced osteonecrosis in rabbits were randomly divided into five groups: A (model), B (XACB), C (XACB + MSCs), D (XACB + MSCs + LV), and E (XACB + MSCs + LV-FGF-2) groups. The therapeutic effect was evaluated by Hematoxylin and Eosin (H&E) staining. Immunohistochemical and RT-PCR assays were used to detect the protein and mRNA expression of TNF-α in the femoral head, respectively. Results: At 12 weeks after the operation, the defect in rabbits in group E was completely repaired, while defects in rabbits in the other groups were not completely repaired, and the area of new bone formation was higher, when compared with the other groups (P<0.05). Furthermore, the protein and mRNA expression TNF-α was lower at 3, 6, and 12 weeks after surgery, when compared with the other groups, and the difference was statistically significant (P<0.05). Conclusion: FGF-2/MSCs/XACB could promote the repair of ANFH, and may be correlated to the inhibition of TNF-α expression.

Hip osteonecroses treated with calcium sulfate-calcium phosphate bone graft substitute have different results according to the cause of osteonecrosis: alcohol abuse or corticosteroid-induced

INTRODUCTION

The aim of the study was to assess the factors influencing the final results of treatment of the femoral head osteonecrosis (ONFH) with core decompression and bone substitute grafting. The special interest was focused on comparison between alcohol- and steroid-induced ONFHs.

MATERIAL AND METHODS

In this prospective study, a total of 53 patients (58 hips) in the mean age of 35.5 years were included: 29 had a history of alcohol use (32 hips) and 24 of steroid use (26 hips). The mean follow-up was 4.2 years (minimum 3 years).

RESULTS

At last follow-up, significant improvements were noted in the Harris Hip Score (HHS) (mean 44.0 vs 55.9 points, p < 0.00002) and VAS scores (mean 7.0 vs 5.8 points, p < 0.0002) for the whole ONFH cohort, comparing to pre-operative status. The degree of improvement did not differ between Ficat and Arlet grade II and grade III (mean 14.9 vs 6.2 points, respectively, p = 0.1). No change was found between the final and initial results in this group in the steroid group (HHS mean 42.2 vs 45.5 points, p = 0.5 and VAS mean 6.8 vs 6.5 points, p = 0.5), but the improvement was noted in the alcohol group (HHS mean 45.5 vs 64.4 points, p < 0.0001; VAS mean 7.1 vs 5.2 points, p < 0.0001) comparing to pre-operative status.

CONCLUSIONS

Presented treatment of ONFH significantly improves hip function, offers pain reduction, and gives similar functional improvement for hips scoring grade II and III on the Ficat and Arlet scale. A good response to operative treatment is seen in patients with alcohol-induced ONFH, but not in those with steroid-induced ONFH.

[Effectiveness of multiple small-diameter drilling decompression combined with hip arthroscopy for early osteonecrosis of the femoral head]

Objective

To evaluate the effectiveness of multiple small-diameter drilling decompression combined with hip arthroscopy for early oeteonecrosis of the femoral head (ONFH).

Methods

Between March 2010 and December 2013, 91 patients with early ONFH were treated with the operation of multiple small-diameter drilling decompression combined with hip arthroscopy in 39 cases (53 hips, group A) or with drilling decompression alone in 52 cases (74 hips, group B). The patients in 2 groups had obvious hip pain and limited motion before operation. There was no significant difference in gender, age, etiology, effected side, stage of osteonecrosis, and preoperative Harris score between 2 groups ( P>0.05).

Results

All operations succeeded and all incisions healed by first intention. The operation time was significantly longer in group A [(73.3±10.6) minutes] than in group B [(41.5±7.2) minutes] ( t=8.726, P=0.000). Temporary of sciatic nerve apraxia after operation occurred in 2 patients of group A, and no complication occurred in other patients. Patients were followed up 24-52 months (mean, 39.3 months) in group A and 24-48 months (mean, 34.6 months) in group B. At last follow-up, the Harris scores were 83.34±8.76 in group A and 76.61±9.22 in group B, showing significant differences when compared between 2 groups ( t=-4.247, P=0.029) and when compared with preoperative values in 2 groups ( t=-10.327, P=0.001; t=-8.216, P=0.008). X-ray films showed that the collapse of the femoral head was observed in 6 hips (1 hip at stage Ⅰand 5 hips at stage Ⅱ) in group A, and in 16 hips (4 hips at stageⅠand 12 hips at stage Ⅱ) in group B; and hip arthroplasty was performed. The total effective rates were 88.68% (47/53) in group A and 78.38% (58/74) in group B, respectively; showing significant difference between 2 groups ( χ²=5.241, P=0.041).

Conclusion

Multiple small-diameter drilling decompression combined with hip arthroscopy is effective in pain relief, improvement of hip function, slowing-down the process of femoral head necrosis, delaying the need for total hip arthroplasty in patients with early ONFH.