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.

SrFe12O19-doped nano-layered double hydroxide/chitosan layered scaffolds with a nacre-mimetic architecture guide in situ bone ingrowth and regulate bone homeostasis

Osteoporotic bone defects result from an imbalance in bone homeostasis, excessive osteoclast activity, and the weakening of osteogenic mineralization, resulting in impaired bone regeneration. Herein, inspired by the hierarchical structures of mollusk nacre, nacre exhibits outstanding high-strength mechanical properties, which are in part due to its delicate layered structure. SrFe₁₂O₁₉ nanoparticles and nano-layered double hydroxide (LDH) were incorporated into a bioactive chitosan (CS) matrix to form multifunctional layered nano-SrFe₁₂O₁₉-LDH/CS scaffolds. The compressive stress value of the internal ordered layer structure matches the trabecular bone (0.18 ​MPa). The as-released Mg²⁺ ions from the nano-LDH can inhibit bone resorption in osteoclasts by inhibiting the NFκB signaling pathway. At the same time, the as-released Sr²⁺ ions promote the high expression of osteoblast collagen 1 proteins and accelerate bone mineralization by activating the BMP-2/SMAD signaling pathway. In vivo, the Mg²⁺ ions released from the SrFe₁₂O₁₉-LDH/CS scaffolds inhibited the release of pro-inflammatory factors (IL-1β and TNF-α), while the as-released Sr²⁺ ions promoted osteoblastic proliferation and the mineralization of osteoblasts inside the layered SrFe₁₂O₁₉-LDH/CS scaffolds. Immunofluorescence for OPG, RANKL, and CD31, showed that stable vasculature could be formed inside the layered SrFe₁₂O₁₉-LDH/CS scaffolds. Hence, this study on multifunctional SrFe₁₂O₁₉-LDH/CS scaffolds clarifies the regulatory mechanism of osteoporotic bone regeneration and is expected to provide a theoretical basis for the research, development, and clinical application of this scaffold on osteoporotic bone defects.

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1, SrFe₁₂O₁₉ nanoparticles and LDH were incorporated into a bioactive CS matrix.

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2, SrFe₁₂O₁₉-LDH/CS scaffolds were prepared as a layered scaffold to increase mechanical strength.

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3, The slow release of Mg²⁺ and Sr²⁺ could maintain bone homeostasis.

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4, The scaffolds also promote the formation of new blood vessels.

[Relationship between alien plant invasion and landscape matrix in the water-level fluctuating zone of the Three Gorges Reservoir, China.]

Invasive process of alien species is affected by not only the invaded habitats, but also the surrounding landscape matrix. Understanding the effects of landscape matrix on alien species is of great significance for controlling invasive alien species. We surveyed plant communities along the water-level fluctuating zone (WLFZ) of the Three Gorges Reservoir. Invasive status of alien plant species was evaluated. Totally 10 spatial scales of the surrounding landscape matrix in the scope of 2000 m (including WLFZ) were classified, and 14 landscape indices were applied to analyze the landscape matrix composition and configuration. Using the principal component analysis and correlation analysis, the effects of landscape matrix on the alien invasive plant species and associated scale effect were tested. Results showed that a total of 42 alien invasive plant species were found in the WLFZ, belonging to 17 families and 36 genera. Fuling was a dividing place to differentiate invasive species distribution. The number of the alien invasive species between Fuling and the Three Gorges Dam was found more than that between Fuling and Jiangjin. For the all scales (within 2000 m). The higher the landscape matrix fragmentation was, the more difficult the alien species invading. The higher landscape connectivity was, the easier the alien species invading. The effects of landscape matrix composition and configuration on the invasive plant diversity at large scales (1200-2000 m) was more significant than those at small scales (200-1000 m), in which landscape matrix composition and configuration at 1200-1400 m showed the strongest effect, demonstrating a significant spatial scale effect. Different invasive plant species showed the scale effects of landscape matrix composition and configuration. At all scales, Xanthium strumarium and Bidens frondosa showed weak correlations with landscape indices, but Bidens tripartita and Erigeron canadensis showed strong correlations. Landscape matrix was closely related to invasive plant species, and demonstrated a significant scale effect. The alien invasive plant species could be traced to the landscape matrix at large scales. Grassland and forest patches at the small scales could be used as the 'stepping stone' for the alien species transiting before they arrived at the WLFZ. In order to control alien plants in the WLFZ, land-use management and optimization should be strengthened at different scales of landscape matrix on the basis of enhancement of habitat management. A diversified comprehensive control for alien species should thus be taken into account.

Analysis of Combined Indicators for Risk of Osteoporotic Hip Fracture in Elderly Women

Objective

To compare the accuracy of combined independent risk factors in assessing the risk of hip fractures in elderly women.

Methods

Ninety elderly females who sustained hip fractures (including femoral neck fractures and intertrochanteric fractures) and 110 female outpatients without a hip fracture were included in our cross‐sectional study from 24 November 2017 to 20 May 2019. The age of subjects in the present study was ≥65 years, with the mean age of 78.73 ± 7.77 and 78.09 ± 5.03 years for women with and without elderly hip fractures, respectively. Bone mineral density (BMD), Beta‐carboxy terminal telopeptide (β‐CTX), N‐terminal/mid region (N‐MID), and 25(OH)D levels were analyzed. A novel evaluation model was established to evaluate combined indicators in assessing hip fractures in elderly women.

Results

Compared with the control group, taller height (155.68 ± 6.40 vs 150.97 ± 6.23, P < 0.01), higher levels of β‐CTX (525.91 ± 307.38 vs 330.94 ± 289.71, P < 0.01), and lower levels of total hip BMD (0.662 ± 0.117 vs 0.699 ± 0.111, P = 0.022), femoral neck BMD (0.598 ± 0.106 vs 0.637 ± 0.100, P = 0.009), and 25(OH)D (15.67 ± 7.23 vs 29.53 ± 10.57, P < 0.01) were found in the facture group. After adjustment for confounding factors, logistic regression analysis revealed that 25(OH)D (adjusted OR 0.837 [95% CI 0.790–0.886]; P < 0.01), femoral neck BMD (adjusted OR 0.009 [95% CI 0.000–0.969]; P = 0.048) and height (adjusted OR 1.207 [95% CI 1.116–1.306]; P < 0.01) remained risk factors for hip fractures in elderly women. Then a model including independent risk factors was established. A DeLong test showed the area under the receiver operator characteristic (ROC) (Area under the curve [AUC]) of 25(OH)D was significantly greater than that for femoral neck BMD (P < 0.01) and height (P < 0.01). The AUC of model including 25(OH)D and height was significantly greater than that of other combinations (P < 0.01).

Conclusion

25(OH)D, femoral neck BMD and height were associated with the occurrence of hip fractures in elderly women even after adjustment for confounding factors, and a model including 25(OH)D and height could provide better associated power than other combinations in the assessment of elderly hip fractures.

Intraoperative Correction of Femoral Rotational Deformity Using a Conventional Navigation System and a Smartphone: A Novel Technique

The intraoperatively rotational control of femoral shaft fractures treated with a closed intramedullary interlocking nailing is a challenging problem. A novel surgical technique that includes respective insertions of guidewires into the proximal and distal femur under the guidance of a 2-dimensional fluoroscopy-based navigation system and the measurements of the intersection angle subtended by the proximal and distal guidewires with the smartphone positional software has been designed to provide intraoperatively quantitative parameters of femoral rotation deformation. The comparison of these parameters with preoperative measurement values of the contralateral intact femur on computed tomography images was used to align the proximal and distal femur fragments based on periaxial rotation. The purpose of this study was to evaluate its clinical suitability. Ten adult patients with femoral shaft fractures were attempted to correct intraoperatively femoral rotational deformity using this novel technique. The additional operation time was 20.04 ± 3.27 minutes. The angle of femoral anteversion was 20.85° ± 4.22°, 38.14° ± 19.07°, and 22.77° ± 3.38° in the contralateral intact and preoperatively and postoperatively injured femur, respectively. The mean absolute difference between both limbs was preoperatively 21.55° ± 10.14° with a statistically significant difference ( P = .005) and postoperatively 3.24° ± 1.69° with no statistically significant difference ( P = .092). Our results showed this novel technique could become an effective tool to correct intraoperatively rotational malalignment of femoral fractures.

Synergistic effects of dimethyloxallyl glycine and recombinant human bone morphogenetic protein-2 on repair of critical-sized bone defects in rats

In bone remodeling, osteogenesis is closely coupled to angiogenesis. Bone tissue engineering using multifunctional bioactive materials is a promising technique which has the ability to simultaneously stimulate osteogenesis and angiogenesis for repair of bone defects. We developed mesoporous bioactive glass (MBG)-doped poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) composite scaffolds as delivery vehicle. Two bioactive molecules, dimethyloxalylglycine (DMOG), a small-molecule angiogenic drug, and recombinant human bone morphogenetic protein-2 (rhBMP-2), an osteoinductive growth factor, were co-incorporated into the scaffold. The synergistic effects of DMOG and rhBMP-2 released in the composite scaffolds on osteogenic and angiogenic differentiation of hBMSCs were investigated using real-time quantitative polymerase chain reaction and western blotting. Moreover, in vivo studies were conducted to observe bone regeneration and vascular formation of critical-sized bone defects in rats using micro-computed tomography, histological analyses, Microfil^® perfusion, fluorescence labeling, and immunohistochemical analysis. The results showed that DMOG and rhBMP-2 released in the MBG-PHBHHx scaffolds did exert synergistic effects on the osteogenic and angiogenic differentiation of hBMSCs. Moreover, DMOG and rhBMP-2 produced significant increases in newly-formed bone and neovascularization of calvarial bone defects in rats. It is concluded that the co-delivery strategy of both rhBMP-2 and DMOG can significantly improve the critical-sized bone regeneration.

Association of the g.19074G>A genetic variant in the osteoprotegerin gene with bone mineral density in Chinese postmenopausal women

Primary osteoporosis is a common health problem in postmenopausal women. This study aimed to detect the association of the g.19074G>A genetic variant in the osteoprotegerin gene (OPG) with bone mineral density (BMD) and primary osteoporosis. The created restriction site-polymerase chain reaction method was used to investigate the g.19074G>A genetic variant. The BMD of the femoral neck hip, lumbar spine (L2-4), and total hip were assessed by dual-energy X-ray absorptiometry (DEXA) in 856 unrelated Chinese postmenopausal women. We found significant differences in the BMDs of the femoral neck hip, lumbar spine (L2-4), and total hip among different genotypes; individuals with the GG genotype had significantly higher BMDs than those with the GA and AA genotypes (P < 0.05). Our results indicated that the A allele was an increased risk factor for primary osteoporosis and the g.19074G>A genetic variant of the OPG gene was associated with BMD and primary osteoporosis in Chinese postmenopausal women.

A novel injectable borate bioactive glass cement as an antibiotic delivery vehicle for treating osteomyelitis

Background

A novel injectable cement composed of chitosan-bonded borate bioactive glass (BG) particles was evaluated as a carrier for local delivery of vancomycin in the treatment of osteomyelitis in a rabbit tibial model.

Materials and Methods

The setting time, injectability, and compressive strength of the borate BG cement, and the release profile of vancomycin from the cement were measured in vitro. The capacity of the vancomycin-loaded BG cement to eradicate methicillin-resistant Staphylococcus aureus (MRSA)-induced osteomyelitis in rabbit tibiae in vivo was evaluated and compared with that for a vancomycin-loaded calcium sulfate (CS) cement and for intravenous injection of vancomycin.

Results

The BG cement had an injectability of >90% during the first 3 minutes after mixing, hardened within 30 minutes and, after hardening, had a compressive strength of 18±2 MPa. Vancomycin was released from the BG cement into phosphate-buffered saline for up to 36 days, and the cumulative amount of vancomycin released was 86% of the amount initially loaded into the cement. In comparison, vancomycin was released from the CS cement for up 28 days and the cumulative amount released was 89%. Two months post-surgery, radiography and microbiological tests showed that the BG and CS cements had a better ability to eradicate osteomyelitis when compared to intravenous injection of vancomycin, but there was no significant difference between the BG and CS cements in eradicating the infection. Histological examination showed that the BG cement was biocompatible and had a good capacity for regenerating bone in the tibial defects.

Conclusions

These results indicate that borate BG cement is a promising material both as an injectable carrier for vancomycin in the eradication of osteomyelitis and as an osteoconductive matrix to regenerate bone after the infection is cured.

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.

Novel borate glass/chitosan composite as a delivery vehicle for teicoplanin in the treatment of chronic osteomyelitis

Composite materials composed of borate bioactive glass and chitosan (designated BGC) were investigated in vitro and in vivo as a new delivery system for teicoplanin in the treatment of chronic osteomyelitis induced by methicillin-resistant Staphylococcus aureus (MRSA). In vitro, the release of teicoplanin from BGC pellets into phosphate-buffered saline (PBS), as well as its antibacterial activity, were determined. The compressive strength of the pellets was measured after specific immersion times, and the structure of the pellets was characterized using scanning electron microscopy and X-ray diffraction. In vivo, the tibial cavity of New Zealand White rabbits was injected with MRSA strain to induce chronic osteomyelitis, treated by debridement after 4weeks, implanted with teicoplanin-loaded BGC pellets (designated TBGC) or BGC pellets, or injected intravenously with teicoplanin. After 12weeks' implantation, the efficacy of the TBGC pellets for treating osteomyelitis was evaluated using hematological, radiological, microbiological and histological techniques. When immersed in PBS, the TBGC pellets provided a sustained release of teicoplanin, while the surface of the pellets was converted to hydroxyapatite (HA). In vivo, the best therapeutic effect was observed in animals implanted with TBGC pellets, resulting in significantly lower radiological and histological scores, a lower positive rate of MRSA culture, and an excellent bone defect repair, without local or systemic side effects. The results indicate that TBGC pellets are effective in treating chronic osteomyelitis by providing a sustained release of teicoplanin, in addition to participating in bone regeneration.