Imbalanced bone turnover markers and low bone mineral density in patients with osteonecrosis of the femoral head

Bioinformatics analysis of PANoptosis regulators in the diagnosis and subtyping of steroid-induced osteonecrosis of the femoral head

In this study, we aimed to investigate the involvement of PANoptosis, a form of regulated cell death, in the development of steroid-induced osteonecrosis of the femoral head (SONFH). The underlying pathogenesis of PANoptosis in SONFH remains unclear. To address this, we employed bioinformatics approaches to analyze the key genes associated with PANoptosis. Our analysis was based on the GSE123568 dataset, allowing us to investigate both the expression profiles of PANoptosis-related genes (PRGs) and the immune profiles in SONFHallowing us to investigate the expression profiles of PRGs as well as the immune profiles in SONFH. We conducted cluster classification based on PRGs and assessed immune cell infiltration. Additionally, we used the weighted gene co-expression network analysis (WGCNA) algorithm to identify cluster-specific hub genes. Furthermore, we developed an optimal machine learning model to identify the key predictive genes responsible for SONFH progression. We also constructed a nomogram model with high predictive accuracy for assessing risk factors in SONFH patients, and validated the model using external data (area under the curve; AUC = 1.000). Furthermore, we identified potential drug targets for SONFH through the Coremine medical database. Using the optimal machine learning model, we found that 2 PRGs, CASP1 and MLKL, were significantly correlated with the key predictive genes and exhibited higher expression levels in SONFH. Our analysis revealed the existence of 2 distinct PANoptosis molecular subtypes (C1 and C2) within SONFH. Importantly, we observed significant variations in the distribution of immune cells across these subtypes, with C2 displaying higher levels of immune cell infiltration. Gene set variation analysis indicated that C2 was closely associated with multiple immune responses. In conclusion, our study sheds light on the intricate relationship between PANoptosis and SONFH. We successfully developed a risk predictive model for SONFH patients and different SONFH subtypes. These findings enhance our understanding of the pathogenesis of SONFH and offer potential insights into therapeutic strategies.

PFKP and GPC6 Variants Were Correlated with Alcohol-Induced Femoral Head Necrosis Risk in the Chinese Han Population

Background

Osteonecrosis of the femoral head (ONFH) is a common joint disease caused by excessive drinking, genetic factors, etc. The purpose of this study was to investigate the association between PFKP and GPC6 variants and alcohol-induced ONFH (AIONFH) risk in the Chinese Han population.

Methods

This study genotyped 9 selected single nucleotide polymorphisms (SNPs) in 402 males by Agena MassARRAY Assay. By calculating odds ratios (ORs) and 95% confidence intervals (CIs), we assessed the effect of gene polymorphisms on AIONFH occurrence. False-positive report probability (FPRP) analysis and power were also used to evaluate the significant results. Multifactor dimensionality reduction (MDR) software was also utilized to predict the association between the selected SNPs and AIONFH risk.

Results

The overall analysis showed that PFKP rs10903966 and GPC6 rs7320969 were correlated with AIONFH risk. GPC6 rs4773724 was associated with a reduced risk of AIONFH, while individuals with GPC6 rs9523981 CC genotype had a higher risk of AIONFH than individuals with the other genotypes among people under 42 years old. Based on stratified analysis of necrotic sites, rs7320969 was related to a decreased risk of AIONFH, while rs10903966 and rs9523981 were related to an increased risk of AIONFH. In addition, rs1008993 and rs7320969 were observed to be linked to AIONFH risk in patients at different clinical stages. Meanwhile, there were significant differences in TC, TG, platelet, ApoA1 and ApoB levels among subjects with different genotypes of rs1008993, rs9523981, rs7320969 and rs59624626. The results of MDR showed that rs11251720 and rs7320969 may play a synergistic role in predicting the risk of AIONFH.

Conclusion

PFKP rs10903966 and GPC6 rs9523981 were associated with an increased risk of AIONFH, while GPC6 (rs7320969 and rs4773724) were correlated with a decreased risk of AIONFH. This result will need further experiments to verify.

Composite indices of femoral neck strength predicts the collapse of steroid-associated osteonecrosis of the femoral head: a retrospective study

PURPOSES

The purpose of this study was to investigate the predictive effect exerted by composite indices of femoral neck strength (compressive strength index (CSI), bending strength index (BSI) and impact strength index (ISI) on the femoral head collapse in steroid-associated ONFH patients.

METHODS

Nonoperative steroid-associated osteonecrosis of the femoral head (ONFH) patients from 2017 to 2019 were selected. The patients fell into the collapsed group and the non-collapsed group according to whether the femoral head collapsed. CSI, BSI and ISI were calculated. Moreover, bone turnover markers were measured. The statistical analysis was conducted on the predictive effects of composite indices of femoral neck strength and bone turnover index on ONFH collapse.

RESULTS

A total of 62 patients were included. The mean CSI, BSI and ISI were significantly lower in the collapsed group than those in the non-collapsed group (P < 0.05). CSI, ISI,t-P1NP and β-CTx were suggested as the protective risk factors for the femoral head collapse in ONFH patients. The ISI area under the curve values was 0. 878.The mean survival time of the hips of patients with ISI greater than 0.435 was greater (P < 0.05) than that of patients with ISI less than 0.435.

CONCLUSION

The composite indices of femoral neck strength can predict steroid-associated ONFH femoral head collapse more effectively than the bone turnover markers. The ISI value of 0.435 is a potential cut-off value, lower than this value can predict the early collapse of steroid-associated ONFH.

Animal Models of Femur Head Necrosis for Tissue Engineering and Biomaterials Research

Femur head necrosis, also known as osteonecrosis of the femoral head (ONFH), is a widespread disabling pathology mostly affecting young and middle-aged population and one of the major causes of total hip arthroplasty in the elderly. Currently, there are limited number of different clinical or medication options for the treatment or the reversal of progressive ONFH, but their clinical outcomes are neither satisfactory nor consistent. In pursuit of more reliable therapeutic strategies for ONFH, including recently emerged tissue engineering and biomaterials approaches, in vivo animal models are extremely important for therapeutic efficacy evaluation and mechanistic exploration. Based on the better understanding of pathogenesis of ONFH, animal modeling method has evolved into three major routes, including steroid-, alcohol-, and injury/trauma-induced osteonecrosis, respectively. There is no consensus yet on a standardized ONFH animal model for tissue engineering and biomaterial research; therefore, appropriate animal modeling method should be carefully selected depending on research purposes and scientific hypotheses. In this work, mainstream types of ONFH animal model and their modeling techniques are summarized, showing both merits and demerits for each. In addition, current studies and experimental techniques of evaluating therapeutic efficacy on the treatment of ONFH using animal models are also summarized, along with discussions on future directions related to tissue engineering and biomaterial research. Impact statement Exploration of tissue engineering and biomaterial-based therapeutic strategy for the treatment of femur head necrosis is important since there are limited options available with satisfactory clinical outcomes. To promote the translation of these technologies from benchwork to bedside, animal model should be carefully selected to provide reliable results and clinical outcome prediction. Therefore, osteonecrosis of the femoral head animal modeling methods as well as associated tissue engineering and biomaterial research are overviewed and discussed in this work, as an attempt to provide guidance for model selection and optimization in tissue engineering and biomaterial translational studies.

Global research trends of steroid-induced osteonecrosis of the femoral head: A 30-year bibliometric analysis

OBJECTIVE

To explore the global research trends and hotspots of steroid-induced osteonecrosis of the femoral head (SONFH) through qualitative and quantitative analysis of bibliometrics.

METHODS

All publications on SONFH published from 1992 to 2021 were extracted from the Web of Science Core Collection database. CiteSpace was used for the visualization analysis of major countries, active institutions, productive authors, and the burst of keywords. VOSviewer was used for coupling analysis of countries/regions, institutions, and authors. Microsoft Excel 2017 was used for statistical analysis, drawing bar charts, pie charts, and cumulative area charts. The software of MapInfo was used to draw the distribution map of the publications.

RESULTS

A total of 780 publications were included for analyses. The most productive year was 2020 with 98 records. China was the most influential country with 494 publications, an H-index of 59, and total citations of 16820. The most prolific institution was Shanghai Jiaotong University in China with 53 publications and 998 citations. Clinical Orthopaedics and Related Research (IF = 4.755, 2021) was the most active journal with 26 articles. The hot keywords were "osteonecrosis", "avascular necrosis", "osteogenic differentiation", "proliferation", "PPAR gamma", "apoptosis", "oxidative stress", "genetic polymorphism" and "mesenchymal stem cells". The keywords like "proliferation", "PPAR gamma" and "genome-wide" have emerged in recent years.

CONCLUSION

The number of publications in SONFH has increased significantly in the last three decades. The pathologic mechanism of SONFH gathered most research interests. Genomics and cell molecular biology of SONFH are the research frontiers.

Do biomarkers allow a differentiation between osteonecrosis of the femoral head and osteoarthritis of the hip? - a biochemical, histological and gene expression analysis

OBJECTIVE

Osteonecrosis of the femoral head (ONFH) is a devastating disease of the hip joint. Its early diagnosis is crucial to increase the chances of joint preserving, yet difficult due to similarities with osteoarthritis (OA) of the hip in its clinical appearance. The purpose of this study was to enhance the understanding of ONFH and its pathologic processes in contrast to OA and to identify serum biomarkers helping to improve the diagnosis of the disease.

DESIGN

Bone and bone marrow samples were collected from 24 patients diagnosed with OA and 25 patients with ONFH during total hip replacement surgery. RNA was isolated, histological examination, determination of free reactive oxygen species as well as gene expression and biomarker analysis were performed.

RESULTS

Histological analysis revealed differences in the structural and cellular pattern between the groups. Gene expression analysis revealed a significant upregulation for the genes ASPN, COL1A1, COL2A1 and IL6 and a significant downregulation for HIF1A in ONFH compared to OA group. Analysis of serum biomarkers showed significant differences between the groups for asporin and adiponectin. A final logistical regression model including the parameters adiponectin, asporin and HIF 1α was overall significant, explained 34.5 % of variance and classified 74.5 % of the cases correctly.

CONCLUSION

The combination of adiponectin, asporin and HIF 1α as serum biomarkers revealed a classification accuracy of 74.5 %. The information provided in this study may help to enhance the understanding of pathologic processes in ONFH and to elaborate further aspects of prediction and treatment.

[Predictive effect of femoral neck strength composite indexes on femoral head collapse in non-traumatic osteonecrosis of femoral head]

Objective

To explore the predictive effect of the femoral neck strength composite indexes on femoral head collapse in non-traumatic osteonecrosis of the femoral head (ONFH) compared with bone turnover marker.

Methods

The non-traumatic ONFH patients who were admitted and received non-surgical treatment between January 2010 and December 2016 as the research object. And 96 cases (139 hips) met the selection criteria and were included in the study. There were 54 males (79 hips) and 42 females (60 hips), with an average age of 40.2 years (range, 22-60 years). According to whether the femoral head collapsed during follow-up, the patients were divided into collapsed group and non-collapsed group. The femoral neck width, hip axis length, height, body weight, and bone mineral density of femoral neck were measured. The femoral neck strength composite indexes, including the compressive strength index (CSI), bending strength index (BSI), and impact strength index (ISI), were calculated. The bone turnover marker, including the total typeⅠcollagen amino terminal elongation peptide (t-P1NP), β-crosslaps (β-CTx), alkaline phosphatase (ALP), 25 hydroxyvitamin D [25(OH)D], and N-terminal osteocalcin (N-MID), were measured. The age, gender, height, body weight, body mass index (BMI), bone mineral density of femoral neck, etiology, Japanese Osteonecrosis Investigation Committee (JIC) classification, femoral neck strength composite indexes, and bone turnover marker were compared between the two groups, and the influencing factors of the occurrence of femoral head collapse were initially screened. Then the significant variables in the femoral neck strength composite indexes and bone turnover marker were used for logistic regression analysis to screen risk factors; and the receiver operating characteristic (ROC) curve was used to determine the significant variables' impact on non-traumatic ONFH.

Results

All patients were followed up 3.2 years on average (range, 2-4 years). During follow-up, 46 cases (64 hips) had femoral head collapse (collapsed group), and the remaining 50 cases (75 hips) did not experience femoral head collapse (non-collapsed group). Univariate analysis showed that the difference in JIC classification between the two groups was significant ( Z=-7.090, P=0.000); however, the differences in age, gender, height, body weight, BMI, bone mineral density of femoral neck, and etiology were not significant ( P>0.05). In the femoral neck strength composite indexes, the CSI, BSI, and ISI of the collapsed group were significantly lower than those of the non-collapsed group ( P<0.05); in the bone turnover marker, the t-P1NP and β-CTx of the collapsed group were significantly lower than those of the non-collapsed group ( P<0.05); there was no significant difference in N-MID, 25(OH)D or ALP between groups ( P>0.05). Multivariate analysis showed that the CSI, ISI, and t-P1NP were risk factors for femoral collapse in patients with non-traumatic ONFH ( P<0.05). ROC curve analysis showed that the cut-off points of CSI, BSI, ISI, t-P1NP, and β-CTx were 6.172, 2.435, 0.465, 57.193, and 0.503, respectively, and the area under the ROC curve (AUC) were 0.753, 0.642, 0.903, 0.626, and 0.599, respectively.

Conclusion

The femoral neck strength composite indexes can predict the femoral head collapse in non-traumatic ONFH better than the bone turnover marker. ISI of 0.465 is a potential cut-off point below which future collapse of early non-traumatic ONFH can be predicted.

Treatment of pre-collapse non-traumatic osteonecrosis of the femoral head through Orthopdische Chirurgie München approach combined with autologous bone mixed with β-tricalcium phosphate porous bioceramic bone graft: a retrospective study of mid-term results

Background

This study aimed to evaluate the clinical efficacy of femoral head and neck fenestration combined with autologous bone mixed with β-tricalcium phosphate porous bioceramic bone (light bulb procedure) through Orthopdische Chirurgie München approach (OCM approach) for pre-collapse non-traumatic osteonecrosis of the femoral head(ONFH).

Methods

The clinical data of 47 patients (47 hips) with ONFH were retrospectively reviewed. The Harris hip score (HHS) was used to evaluate the clinical outcomes. Imaging was assessed by X-ray. Clinical failure was defined as postoperative total hip arthroplasty (THA) or the HHS was poor (< 70). The Kaplan–Meier survival curve was used to conduct a univariate analysis of risk factors. The analysis factors included gender, age, International Association Research Circulation Osseous (ARCO) stage, etiology, body mass index (BMI), 25-hydroxyvitamin D (25(OH)D), and type I collagen carboxy-terminal peptide (CTX). The COX multivariate risk model was used to analyze the risk factors.

Results

All the 47 hips were followed up for 24–58 months, with an average of 45 months. The Harris score (76.29 ± 10.38) at the last follow-up was significantly higher than the preoperative HHS (64.45 ± 2.93) (P < 0.05). The postoperative HHS was excellent with a success rate of 36.17%. Postoperative imaging evaluation showed that 9 hips improved, 28 hips stabilized, and 10 hips progressed. Moreover, 17 out of 47 hips were defined as a postoperative clinical failure and the success rate was 63.83%. 25(OH)D and preoperative ARCO stage were risk factors for postoperative clinical failure (P < 0.05). The COX multivariate risk model analysis showed that IIIA stage was an independent risk factor for postoperative clinical failure (P < 0.05).

Conclusions

The head and neck fenestration and bone grafting via the OCM approach in the treatment of non-traumatic ONFH in the pre-collapse stage can achieve good clinical outcomes. 25(OH)D deficient patients and ARCO IIIA patients had a higher failure rate of bone graft using this approach.

Hip pathologies in mucopolysaccharidosis type III

Background

Mucopolysaccharidosis type III (MPS III) comprises a group of rare lysosomal storage diseases. Although musculoskeletal symptoms are less pronounced than in other MPS subtypes, pathologies of hip and spine have been reported in MPS III patients. The purpose of this study was to describe hip pathologies and influencing parameters in MPS III patients.

Methods

A retrospective chart review was performed for 101 MPS III patients. Thirty-two patients met the inclusion criteria of enzymatically or genetically confirmed diagnosis and anteroposterior radiograph of the hips. Modified Ficat classification, Wiberg’s center-edge angle, and Reimer’s migration percentage were measured.

Results

The mean age at data assessment was 11.0 years (SD 5.7). Osteonecrosis of the femoral head was observed in 17/32 patients. No statistically significant association was found between these changes and age, sex, or MPS III subtype. Patients with a severe phenotype showed significantly higher rates of osteonecrosis (14/17) than patients with an intermediate phenotype. Hip dysplasia was present in 9/32 patients and was significantly associated with osteonecrosis of the femoral head (p = 0.04).

Conclusions

The present study demonstrates a high rate of hip pathologies in MPS III patients. Hip dysplasia and severe phenotype were significantly correlated with osteonecrosis of the femoral head. Therefore, radiographs of the hips are highly recommended in baseline and follow-up assessments of MPS III patients.

Trial registration

Retrospectively registered.

Effects of hypoxia environment on osteonecrosis of the femoral head in Sprague-Dawley rats

INTRODUCTION

Osteonecrosis of the femoral head (ONFH) is a disease in which the blood supply of the femoral head is interrupted or damaged, resulting in joint dysfunction. Hypoxic environments increase the expression of EPO, VEGF, and HIF causes vascular proliferation and increases the blood supply. It also causes the organism to be in a state of hypercoagulability and increases thrombosis. Therefore, the purpose of this study was to explore the occurrence of ONFH after the use of glucocorticoids (GCs) under conditions of hypoxia tolerance for a long time.

MATERIALS AND METHODS

Sprague-Dawley rats were fed in a hypobaric hypoxic chamber at an altitude of 4000 m, the whole blood viscosity, and plasma viscosity were determined to analyze the blood flow and hemagglutination. Western blotting, polymerase chain reaction, and immunohistochemistry were used to detect EPO, VEGF, CD31, and osteogenesis related proteins. Femoral head angiography was used to examine the local blood supply and micro-CT scanning was used to detect the structure of the bone trabecula.

RESULTS

Under hypoxic environments, the expression of EPO and VEGF increased, which increased the local blood supply of the femoral head, but due to more severe thrombosis, the local blood supply of the femoral head decreased.

CONCLUSIONS

Hypoxic environments can aggravate ONFH in SD rats; this aggravation may be related to the hypercoagulable state of the blood. We suggest that long-term hypoxia should be regarded as one of the risk factors of ONFH and we need to conduct a more extensive epidemiological investigation on the occurrence of ONFH in hypoxic populations.

IL-15 deficiency alleviates steroid-induced osteonecrosis of the femoral head by impact osteoclasts via RANKL-RANK-OPG system

Background

Whether IL-15 is involved in the development of steroid-induced osteonecrosis of the femoral head (ONFH) is investigated.

Methods

C57BL/6 J and l15^−/−mice were injected with methylprednisolone to induce wide type osteonecrosis (WT ON) and IL-15 deficiency osteonecrosis (IL-15^−/− ON). Hematoxylin-Eosin (H&E) staining and micro-computed tomography (micro-CT) scanning was used to detect the microstructure. The differentiation and formation of osteoclasts were determined with colony-forming unit-granulocyte macrophages (CFU-GM), colony-forming unit-macrophage/mononuclear (CFU-M) per tibia, and tartrate-resistant acid phosphatase (TRACP or TRAP) positive cells. Serum interleukin (IL)-15, osteocalcin, bone alkaline phosphatase (BAP), bone Gla protein (BGP), and TRACP were assayed with enzyme-linked immunosorbent assay (ELISA). The receptor activator of nuclear factor-κB (RANK), RANK ligand (RANKL), and osteoprotegerin (OPG) in the femoral heads were detected by Western blot. CD34 staining was performed to detect microvascular density.

Results

IL-15 secretion was increased in the femoral heads and the serum of steroid-induced ONFH mice. IL-15 deficiency may lead to up-regulated vessel remodeling, improved microstructure, and up-regulated serum osteocalcin, BAP, and BGP secretion. Both the expression of RANKL/RANK/OPG and osteoclast differentiation and formation can be down-regulated by IL-15 deficiency.

Conclusion

IL-15 deficiency alleviates steroid-induced ONFH by impact osteoclasts via RANKL-RANK-OPG system.

Upregulating MicroRNA-410 or Downregulating Wnt-11 Increases Osteoblasts and Reduces Osteoclasts to Alleviate Osteonecrosis of the Femoral Head

BACKGROUND

Little is known regarding the functional role of microRNA-410 (miR-410) in osteonecrosis of the femoral head (ONFH); hence, the aim of the present study was to investigate miR-410 targeting Wnt-11 to modulate the osteogenic and osteoclastic mechanism in the prevention of ONFH.

METHODS

Fifteen ONFH samples and 15 normal samples were gathered. The pathological changes of the femoral head, osteoblasts, and osteoclasts in the clinical samples were observed. The rat model of ONFH was injected with agomir-miR-410, Wnt-11-siRNA, or oe-Wnt-11. MiR-410; Wnt-11; osteoblast-related factors alkaline phosphatase (ALP), bone gamma-carboxyglutamate protein (BGLAP), and Collα1 expression; and osteoclast-related factors acid phosphatase 5 (ACP5), cathepsin K (CTSK), and MMP9, as well as Bcl-2 and Bax expression, were tested by RT-qPCR and western blot analysis. The osteogenic function index ALP and OCN together with osteoclast function index NTX-1 and CTX-1 in serum was tested by ELISA.

RESULTS

MiR-410, ALP, BGLAP, and Collα1 degraded as well as Wnt-11, ACP5, CTSK, and MMP9 enhanced in ONFH tissues of the clinical samples. Upregulated miR-410 and downregulated Wnt-11 enhanced bone mineral density (BMD) and BV/TV of rats, heightened the BMD level of the femoral shaft, femoral head, and spinal column, and also raised the serum calcium and phosphorus levels of rats, while restrained apoptosis of osteocytes, elevated OCN, ALP, BGLAP, and Collα1 expression and declined ACP5, CTSK, NTX-1, CTX-1, and MMP9 expression in rats.

CONCLUSION

This study suggested that upregulating miR-410 or downregulating Wnt-11 increases osteoblasts and reduces osteoclasts to alleviate the occurrence of ONFH. Thus, miR-410 may serve as a potential target for the treatment of ONFH.

Betaine alleviates alcohol-induced osteonecrosis of the femoral head via mTOR signaling pathway regulation

Osteonecrosis of the femoral head (ONFH) is usually caused by chronic and excessive alcohol dependency, and this condition largely suppresses the osteogenic differentiation of bone mesenchymal stem cells (BMSCs). As a trimethyl derivative of glycine, betaine is an important human nutrient that regulates a series of vital biological processes, including oxidative stress, inflammatory responses, osteoblast differentiation and cellular apoptosis. However, no study has investigated the role of betaine in alcohol-induced ONFH. In this study, we hypothesized that betaine might have protective effects on ethanol-treated BMSCs and decrease the morbidity of alcohol-induced ONFH in a rat model. In vitro, we found that ethanol significantly downregulated the expression of osteocalcin (OCN), collagen 1 (COL1) and RUNX2 via activating the mammalian target of rapamycin (mTOR) signaling cascade. However, the inhibitory effects were rescued by betaine co-treatment at concentrations of 1 mM and 10 mM. In vivo, the typical ONFH pathological changes in a rat model of alcohol-induced ONFH were investigated by using multiple methods, including hematoxylin-eosin staining, micro-CT scans, TdT-mediated dUTP nick end labeling (TUNEL) assays and immunohistochemical staining for OCN and COL1. Osteonecrotic lesions of the femoral head could be alleviated by betaine as evidenced by significant histological and radiological improvements. Collectively, betaine plays a protective role against ethanol-induced suppression of osteogenesis and mineralization of hBMSCs and is thus a potential pharmacotherapy for alcohol-induced ONFH in vivo.

Biomarkers of bone healing induced by a regenerative approach based on expanded bone marrow-derived mesenchymal stromal cells

BACKGROUND

Safety and feasibility of a regenerative strategy based on the use of culture-expanded mesenchymal stromal cells (MSCs) have been investigated in phase 2 trials for the treatment of nonunion and osteonecrosis of the femoral head (ONFH). As part of the clinical study, we aimed to evaluate if bone turnover markers (BTMs) could be useful for predicting the regenerative ability of the cell therapy product.

MATERIALS AND METHODS

The bone defects of 39 patients (nonunion: n = 26; ONFH: n = 13) were treated with bone marrow-derived MSCs, expanded using a clinical-grade protocol and combined with biphasic calcium phosphate before implantation. Bone formation markers, bone-resorption markers and osteoclast regulatory proteins were measured before treatment (baseline) and after 12 and 24 weeks from surgery. At the same time-points, clinical and radiological controls were performed to evaluate the bone-healing progression.

RESULTS

We found that C-Propeptide of Type I Procollagen (CICP) and C-terminal telopeptide of type-I collagen (CTX) varied significantly, not only over time, but also according to clinical results. In patients with a good outcome, CICP increased and CTX decreased, and this trend was observed in both nonunion and ONFH. Moreover, collagen biomarkers were able to discriminate healed patients from non-responsive patients with a good diagnostic accuracy.

DISCUSSION

CICP and CTX could be valuable biomarkers for monitoring and predicting the regenerative ability of cell products used to stimulate the repair of refractory bone diseases. To be translated in a clinical setting, these results are under validation in a currently ongoing phase 3 clinical trial.

Stem cell therapy in bilateral osteonecrosis: computer-assisted surgery versus conventional fluoroscopic technique on the contralateral side

PURPOSE

Surgical management of osteonecrosis with core decompression with stem cell therapy is a new procedure. The technique is performed with fluoroscopic guidance. This study attempts to determine if computer-navigated technique can improve the procedure.

METHODS

Thirty consecutive patients with bilateral symptomatic osteonecrosis without collapse were included in this study during the year 2011. A prospective, randomized, and controlled study was conducted on 60 hips (bilateral osteonecrosis) using conventional fluoroscopy technique on one side and computer-based navigation on the contralateral side. Bone marrow aspirated from the two iliac crests was mixed before concentration. Each side received the same volume of concentrated bone marrow and the same number of cells 110,000 ± 27,000 cells (counted as CFU-F).

RESULTS

Computer navigation achieved better parallelism to the ideal position of the trocar, with better trocar placement as regards to tip-to-subchondral distance and ideal centre position within the osteonecrosis for injection of stem cells. Using computer navigation took fewer attempts to position the trocar, used less fluoroscopy time, and decreased the radiation exposure as compared with surgery performed with conventional fluoroscopy. At the most recent follow-up (6 years), increasing the precision with computer navigation resulted in less collapse (7 versus 1) and better volume of repair (13.4 versus 8.2 cm³) for hips treated with the computer-assisted technique.

CONCLUSIONS

The findings of this study suggest that computer navigation may be safely used in a basic procedure for injection of stem cells.