Dysregulated miR-127-5p contributes to type II collagen degradation by targeting matrix metalloproteinase-13 in human intervertebral disc degeneration.

BACKGROUND: Intervertebral disc degeneration (IDD) is a chronic disease associated with the degradation of extracellular matrix (ECM). Matrix metalloproteinase (MMP)-13 is a major enzyme that mediates the degradation of ECM components. MMP-13 has been predicted to be a potential target of miR-127-5p. However, the exact function of miR-127-5p in IDD is still unclear. OBJECTIVE: We designed this study to evaluate the correlation between miR-127-5p level and the degeneration of human intervertebral discs and explore the potential mechanisms. METHODS: miR-127-5p levels and MMP-13 mRNA levels were detected by quantitative real-time polymerase chain reaction (qPCR). To determine whether MMP-13 is a target of miR-127-5p, dual luciferase reporter assays were performed. miR-127-5p mimic and miR-127-5p inhibitor were used to overexpress or downregulate miR-127-5p expression in human NP cells, respectively. Small interfering RNA (siRNA) was used to knock down MMP-13 expression in human NP cells. Type II collagen expression in human NP cells was detected by qPCR, western blotting, and immunofluorescence staining. RESULTS: We confirmed that miR-127-5p was significantly downregulated in nucleus pulposus (NP) tissue of degenerative discs and its expression was inversely correlated with MMP-13 mRNA levels. We reveal that MMP-13 may act as a target of miR-127-5p. Expression of miR-127-5p was inversely correlated with type II collagen expression in human NP cells. Moreover, suppression of MMP-13 expression by siRNA blocked downstream signaling and increased type II collagen expression. CONCLUSION: Dysregulated miR-127-5p contributed to the degradation of type II collagen by targeting MMP-13 in human IDD. Our findings highlight that miR-127-5p may serve as a new therapeutic target in IDD.

Analysis of Sagittal Parameters in Patients Undergoing One- or Two-Level Closing Wedge Osteotomy for Correcting Thoracolumbar Kyphosis Secondary to Ankylosing Spondylitis.

STUDY DESIGN: Retrospective analysis of clinical records. OBJECTIVE: To assess and compare the improvement in sagittal balance after one- or two-level closing wedge osteotomy for correcting thoracolumbar kyphosis secondary to ankylosing spondylitis (AS). SUMMARY OF BACKGROUND DATA: Closing wedge osteotomy represents a common approach to correct kyphosis in AS. Although several reports have described the outcomes of one- or two-level closing wedge osteotomy in terms of sagittal parameters, data comparing the outcomes of these procedures are scarce. METHODS: Between January 2010 and December 2014, 22 patients with AS underwent closing wedge osteotomy (one-level, 12 patients; two-level, 10 patients) for correcting thoracolumbar kyphosis (mean follow-up, 24.8 months; range, 12-60 months). Preoperative and postoperative chin-brow vertical angle, and the sagittal parameters of the vertebral osteotomy segment were documented and compared. Perioperative and postoperative complications were also recorded. RESULTS: The chin-brow vertical angle improved significantly, from 55.0°â€Š±â€Š27.3° to 4.7°â€Š±â€Š4.9° and from 38.2°â€Š±â€Š14.9° to 3.2°â€Š±â€Š5.4° in the one-level and two-level groups, respectively. The total correction (thoracic kyphosis and lumbar lordosis) was 32.8°â€Š±â€Š18.2° and 53.7°â€Š±â€Š9.4° in the one-level and two-level groups, respectively. No death, complete paralysis, or vascular complications occurred during the procedure, but cerebrospinal fluid leak was noted in one and two patients from the one-level and two-level groups, respectively. A distal pedicle screw adjacent to the osteotomy segment became loose during surgery in one patient (one-level group). Postoperatively, no transient neurological deficit, infection, delay union, or loosening or breaking of the internal fixation devices was observed. Osteotomy site fusion was achieved in all patients, and the Oswestry Disability Index scores improved significantly. CONCLUSION: Closing wedge osteotomy is effective and safe for correcting thoracolumbar kyphosis in patients with AS. Significant correction and improvement in all sagittal parameters were noted in both groups, but two-level closing wedge osteotomy provided better correction. LEVEL OF EVIDENCE: 3.

Initial CT-guided percutaneous biopsy of vertebral lesions: Evaluation of its diagnostic accuracy and clinical value.

This study aimed to examine the diagnostic accuracy and clinical efficacy of initial CT-guided percutaneous biopsy of the vertebral lesions. A total of 305 percutaneous biopsies of the vertebral lesions were performed under either CT guidance (n=127) or C-arm guidance (n=178). The diagnostic accuracy rate was evaluated by comparing the histopathological diagnosis with the ultimate diagnosis. The histopathological diagnosis was consistent with the ultimate diagnosis in 108 (85.0%, 108/127) cases of CT-guided biopsy and in 135 (75.8%, 135/178) cases of C-arm guided biopsy and there was a significant difference. The accuracy of diagnosis based on biopsies varied with different diseases, including primary benign or malignant tumors, metastatic tumors, inflammatory lesions and fractures. A second biopsy or further examinations were required for patients with negative result obtained in the initial biopsy. The complication rate was 3.1% (4/127) in CT-guided biopsy and 7.3% (13/178) in C-arm guided biopsy. In conclusion, CT-guided percutaneous biopsy is an accurate and safe technique for biopsy of the vertebral lesions.

Total hip arthroplasty with subtrochanteric femoral shortening osteotomy for high hip dislocation.

OBJECTIVE: To evaluate the outcomes of total hip arthroplasty (THA) with subtrochanteric femoral shortening osteotomy for high hip dislocation. METHODS: In this retrospective study, the results of 24 primary THAs with acetabular reconstruction and subtrochanteric femoral shortening osteotomy in 21 patients with high hip dislocation were evaluated. The acetabula were reconstructed with cemented or uncemented cups and bone grafting. Transverse subtrochanteric femoral shortening osteotomies were applied and the osteotomy sites treated by bone grafting and cable fixation. Assessment was by Hip Harris scores and radiographic evaluation. RESULTS: The mean follow-up time was 42 months (18-108 months), three cases being lost to follow-up 18-27 months postoperatively. The HHS improved from 47.5 ± 8.7 to 88.5 ± 3.1. The mean length of femoral segments removed was 2.5 ± 0.8 cm (range, 1.0-4.5 cm) and mean acetabular inclination 43° ± 5° (range, 31°-54°). Caudalization of the femoral head center was 3.2 ± 3.0 mm (range, -3 to 12 mm) and lateralization 4.0 ± 4.0 mm (range, -9 to 11 mm). Mean greater trochanter height relative to theoretical hip center was 5.2 ± 1.0 cm (range, 3.5-7.1 cm) preoperatively and 0.2 ± 0.6 cm (range, -0.9 to 1.2 cm) postoperatively. Intraoperative trochanteric fractures occurred in three cases and sciatic nerve palsy in one. CONCLUSION: THA with subtrochanteric femoral shortening osteotomy is an effective technique for treating high hip dislocation. Its advantages include improvement in limb imbalance and decreased risk of sciatic nerve injury.