Autologous Costal Cartilage Grafting for a Large Osteochondral Lesion of the Femoral Head: A 1-Year Single-Arm Study with 2 Additional Years of Follow-up.

BACKGROUND: There is currently no ideal treatment for osteochondral lesions of the femoral head (OLFH) in young patients. METHODS: We performed a 1-year single-arm study and 2 additional years of follow-up of patients with a large (defined as >3 cm 2 ) OLFH treated with insertion of autologous costal cartilage graft (ACCG) to restore femoral head congruity after lesion debridement. Twenty patients ≤40 years old who had substantial hip pain and/or dysfunction after nonoperative treatment were enrolled at a single center. The primary outcome was the change in Harris hip score (HHS) from baseline to 12 months postoperatively. Secondary outcomes included the EuroQol visual analogue scale (EQ VAS), hip joint space width, subchondral integrity on computed tomography scanning, repair tissue status evaluated with the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score, and evaluation of cartilage biochemistry by delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) and T2 mapping. RESULTS: All 20 enrolled patients (31.02 ± 7.19 years old, 8 female and 12 male) completed the initial study and the 2 years of additional follow-up. The HHS improved from 61.89 ± 6.47 at baseline to 89.23 ± 2.62 at 12 months and 94.79 ± 2.72 at 36 months. The EQ VAS increased by 17.00 ± 8.77 at 12 months and by 21.70 ± 7.99 at 36 months (p < 0.001 for both). Complete integration of the ACCG with the bone was observed by 12 months in all 20 patients. The median MOCART score was 85 (interquartile range [IQR], 75 to 95) at 12 months and 75 (IQR, 65 to 85) at the last follow-up (range, 24 to 38 months). The ACCG demonstrated magnetic resonance properties very similar to hyaline cartilage; the median ratio between the relaxation times of the ACCG and recipient cartilage was 0.95 (IQR, 0.90 to 0.99) at 12 months and 0.97 (IQR, 0.92 to 1.00) at the last follow-up. CONCLUSIONS: ACCG is a feasible method for improving hip function and quality of life for at least 3 years in young patients who were unsatisfied with nonoperative treatment of an OLFH. Promising long-term outcomes may be possible because of the good integration between the recipient femoral head and the implanted ACCG. LEVEL OF EVIDENCE: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Dimethyloxaloylglycine increases bone repair capacity of adipose-derived stem cells in the treatment of osteonecrosis of the femoral head.

Mesenchymal stem cells have been widely studied to promote local bone regeneration of osteonecrosis of the femoral head (ONFH). Previous studies observed that dimethyloxaloylglycine (DMOG) enhanced the angiogenic and osteogenic activity of mesenchymal stem cells by activating the expression of hypoxia inducible factor-1α (HIF-1α), thereby improving the bone repair capacity of mesenchymal stem cells. In the present study, it was investigated whether DMOG could increase the bone repair capacity of adipose-derived stem cells (ASCs) in the treatment of ONFH. Western blot analysis was performed to detect HIF-1α protein expression in ASCs treated with different concentrations of DMOG. The results showed DMOG enhanced HIF-1α expression in ASCs in a dose-dependent manner at least for 7 days. Furthermore, DMOG-treated ASCs were transplanted into the necrotic area of a rabbit model of ONFH to treat the disease. Four weeks later, micro-computed tomography (CT) quantitative analysis showed that 58.8±7.4% of the necrotic area was regenerated in the DMOG-treated ASCs transplantation group, 45.5±3.4% in normal ASCs transplantation group, 25.2±2.8% in only core decompression group and 10.6±2.6% in the untreated group. Histological analysis showed that transplantation of DMOG-treated ASCs clearly improved the bone regeneration of the necrotic area compared with the other three groups. Micro-CT and immunohistochemical analysis demonstrated the revasculation of the necrotic area were also increased significantly in the DMOG-treated ASC group compared with the control groups. Thus, it is hypothesized that DMOG could increase the bone repair capacity of ASCs through enhancing HIF-1α expression in the treatment of ONFH.

Relationship between the Apolipoprotein AI, B gene polymorphism and the risk of non-traumatic osteonecrosis.

BACKGROUND: Previous studies suggested that Apolipoprotein AI (ApoAI) and apolipoprotein B (ApoB) gene polymorphisms may result in lipid metabolism disorders. Genetic polymorphisms in these genes may be associated with the occurrence of osteonecrosis. METHODS: We designed a case-control study including 429 patients of osteonecrosis and 368 age- and sex-matched control subjects. Polymerase chain reaction was used to amplify the DNA fragments in promoter -75 G > A of ApoAI gene and EcoR I, Xba I and 3'-VNTR of ApoB gene in osteonecrosis patients and healthy controls. We utilized polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to genotype these four single nucleotide polymorphisms (SNPs). RESULTS: For -75 G > A polymorphism of ApoAI, AA genotype frequency (0.501) was significantly higher in patients with osteonecrosis than that in control (0.462) subjects (P <0.001), GA genotype frequency (0.170) was significantly lower than that in the control (0.310) group (P <0.0001). In osteonecrosis patients, the odds ratio (OR) of A allele was 3.932 (95% CI: 3.0847 ~ 5.0123), which suggested that subjects carrying A allele of promoter region -75 G > A of ApoAI gene had higher susceptibility to osteonecrosis than G allele carriers. The genotype and allele frequency distributions showed no significant difference in EcoR I, Xba Iand 3'-VNTR loci of ApoB gene between the osteonecrosis group and control group. CONCLUSION: Our study suggested that ApoAI gene -75G > A polymorphism may be associated with susceptibility to osteonecrosis in Chinese population. However, our results need further investigation with large sample size and various populations.

Diagnosis, management, and prevention of prosthetic joint infections.

As the number of joint prosthesis replacements worldwide increases exponentially, prosthetic joint infection (PJI), associated with prosthetic implants, has become a devastating complication associated with high morbidity and substantial cost. Patients who develop PJIs typically require extended hospitalization, additional surgical procedures, and long courses of parenteral antimicrobials. Defining the diagnostic criteria is complicated by patient heterogeneity. No single routinely used clinical test has been shown to achieve the ideal sensitivity, specificity, and accuracy for the diagnosis of PJI. Goals of treatment are to eradicate infection, prevent recurrence, and preserve mechanical joint function. Meanwhile, preventive strategies should be used in a timely and appropriate fashion. The present review will discuss the diagnosis, management, and prevention of PJI.

HIF-1α transgenic bone marrow cells can promote tissue repair in cases of corticosteroid-induced osteonecrosis of the femoral head in rabbits.

Although corticosteroid-induced osteonecrosis of the femoral head (ONFH) is common, the treatment for it remains limited and largely ineffective. We examined whether implantation of hypoxia inducible factor-1α (HIF-1α) transgenic bone marrow cells (BMCs) can promote the repair of the necrotic area of corticosteroid-induced ONFH. In this study, we confirmed that HIF-1α gene transfection could enhance mRNA expression of osteogenic genes in BMCs in vitro. Alkaline phosphatase activity assay and alizarin red-S staining indicated HIF-1α transgenic BMCs had enhanced osteogenic differentiation capacity in vitro. Furthermore, enzyme linked immunosorbent assay (ELISA) for VEGF revealed HIF-1α transgenic BMCs secreted more VEGF as compared to normal BMCs. An experimental rabbit model of early-stage corticosteroid-induced ONFH was established and used for an evaluation of cytotherapy. Transplantation of HIF-1α transgenic BMCs dramatically improved the bone regeneration of the necrotic area of the femoral head. The number and volume of blood vessel were significantly increased in the necrotic area of the femoral head compared to the control groups. These results support HIF-1α transgenic BMCs have enhanced osteogenic and angiogenic activity in vitro and in vivo. Transplantation of HIF-1α transgenic BMCs can potentially promote the repair of the necrotic area of corticosteroid-induced ONFH.

Efficacy of leukocyte- and platelet-rich plasma gel (L-PRP gel) in treating osteomyelitis in a rabbit model.

Leukocyte- and platelet-rich plasma gel (L-PRP gel), a new autologous product which was previously utilized in several surgical procedures to enhance tissue healing, is now increasingly used as a promising treatment method for infections. In this study, we investigated the antibacterial property of L-PRP gel against Methicillin-resistive Staphylococcus aureus (MRSA, ATCC 43300) in a rabbit model of osteomyelitis. Tibial osteomyelitis was induced in 40 New Zealand white rabbits using the MRSA strain. Three weeks after induction, the rabbits with tibial osteomyelitis were randomly divided into four groups: Control group (no treatment); Van group (debridement and parenteral treatment with vancomycin alone); L-PRP gel + Van group (debridement and local L-PRP gel injection, plus parenteral treatment with vancomycin); L-PRP gel group (debridement and local L-PRP gel injection). All rabbits were sacrificed 6 weeks after debridement. The antibacterial efficacy was evaluated by radiological, microbiological, and histological examinations. Newly formed bone was also quantified. The best therapeutic efficacy, including infection elimination and bone defect repair, was observed in the L-PRP gel + Van group. Although not comparable to vancomycin, L-PRP gel also exibited antimicrobial efficacy in vivo. We believe that a combination of L-PRP gel and antibiotics could be a favorable alternative for the treatment of osteomyelitis.

Edaravone, a novel free radical scavenger, prevents steroid-induced osteonecrosis in rabbits.

OBJECTIVE: To investigate the efficacy of edaravone, a novel free radical scavenger, on preventing steroid-induced osteonecrosis (ON) in a rabbit model. METHODS: Thirty-six New Zealand white rabbits were divided into control (C; n = 6), steroid-administered (S; n = 15) and edaravone-administered groups (E; n = 15) after receiving an established protocol of steroid-induced ON. Before and after steroid administration, plasma levels of reduced glutathione (GSH) and lipid peroxidation (LPO) were measured for oxidative stress. Two weeks later bilateral proximal femurs were dissected for micro-CT-based micro-angiography, and the presence or absence of ON and intravascular thrombi were examined histopathologically. Immunohistochemical examination of oxidative injury in bone tissue was conducted using the anti-8-hydoxy-2'-deoxyguanosine and anti-malondialdehyde mAbs. RESULTS: The incidence of ON in the E group (20%) was significantly lower than in the S group (73%). Three to five days after steroid administration, the plasma GSH level was significantly higher and LPO level was significantly lower in the E group than the S group. Compared with the S group, there were significantly more small-sized perfusion vessels and fewer large-sized dilated vessels in the E group. Thrombosis incidence was significantly lower in the E group than the S group. Intraosseous vessels and haematopoietic cells that sustained oxidative injury were significantly fewer in the E group than the S group. CONCLUSION: Edaravone exerted beneficial effects on reducing incidence of steroid-induced ON by suppressing the accumulation of lipid peroxidative products and oxidative DNA damage in endothelial cells and haematopoietic cells.