AbstractBackgroudIntervertebral disc degeneration (IDD) is one of the common degenerative diseases. Due to ethical constraints, it is difficult to obtain sufficient research on humans, so the use of an animal model of IDD is very important to clarify the pathogenesis and treatment mechanism of the disease.MethodsIn this study, thirty 2‐month‐old mice were selected for operation to establish a coccygeal IDD model. The distal tail portion of the tail (beyond the 17th coccygeal vertebra) and a small piece of skin above the 8th coccygeal vertebra were excised, and the two incisions were brought together after flexion, and secured with sutures. The heights and signal intensities of the intervertebral discs (IVDs) were assessed using microcomputed tomography (μCT) and magnetic resonance imaging (MRI) at 0, 6, 12 weeks postoperatively. The overall tissue morphology, cell distribution and density, and extracellular matrix of the IVDs were also assessed using Hematoxylin and Eosin (HE), Safranin O‐Fast Green and immunohistochemical staining.ResultsAll mice in the experimental group survived after the operation, and there were no complications such as wound infection, tail necrosis and suture shedding. The experimental results demonstrated that the suturing method can successfully initiate IDD. Different severity levels of IDD can be induced by controlling the bending angle of the IVDs within the tail loop; however, for consistency, histologic and imaging results should be obtained at the same bending angle and looping period.ConclusionsThis IDD model is an effective method for studying the etiology and treatment of degenerative IVD disease.

The collagen and elastin are important components of extracellular matrix (ECM) in the nucleus pulposus (NP), which can produce water-insoluble proteins through cross-linkages to stabilize ECM. Lysyl oxidase (LOX), a copper-dependent amine oxidase, insolubilizes ECM proteins to keep the stability of ECM by initiating collagen and elastin cross-linkages. The present study aimed to investigate the relationships between intervertebral disc (IVD) degeneration and LOX expression in human NP. A total of 22 cases with lumbar IVD degeneration were designed to the observed group and the control group consisted of 4 young patients with the need of surgically removing the IVD due to lumbar vertebra fracture caused by sudden trauma. These patients were grouped based on Pfirrmann grades of IVDs. The control group represented grade I (group A) and the observed group was subdivided into 4 group: Grade II (group B), grade III (group C), grade IV (group D) and grade V (group E). The herniated NP of each group was prepared for immunohistochemistry, western blotting and reverse transcription-quantitative PCR. The present results showed that the number of NP cells and the components of ECM were significantly lower in the observed group than in the control group. There was an inverse association of the expression rate of LOX NP cells with Pfirrmann grades and age. The protein expression of LOX in group A, B, C, D and E was 2.69±0.24, 2.24±0.32, 1.34±0.19, 1.3±0.32 and 1.01±0.12, respectively. The mRNA expression of LOX in Group A, B, C, D and E was 1±0.03, 0.83±0.07, 0.71±0.09, 0.53±0.09 and 0.27±0.05, respectively. With increasing IVD degeneration, the protein and mRNA expression levels of LOX in NP decreased gradually. Taken together, the findings of the present study revealed that the protein and mRNA expression levels of LOX were decreased with increasing IVD degeneration. These findings provide new insights that LOX might involve in the occurrence and development of IVD degeneration.

Tendons and ligaments are essential connective tissues that attach muscle to bone and bone to bone, thus enabling the storage and transfer of kinetic energy under high-intensity and repetitive conditions. The incidence of tendon and ligament injuries caused by sports has shown an increasing trend over the years, as the population's participation in daily sporting activities continues to rise. Moreover, during the late gestational and postnatal stages, the tendon repair mechanism shifts from complete regeneration to a repair process that is characterized by some scar tissue formation. Current understanding of tendon recovery has shifted from initially focusing on local cell proliferation and extracellular matrix (ECM) synthesis at the injury sites to emphasizing dynamic matrix remodeling, cell heterogeneity, and the integrated regulation of multiple signaling pathways. Tenomodulin (TNMD) is a key regulator of tendon maturation, differentiation, and remodeling, and is recognized as a crucial marker for the tendon lineage. The review aims to systematically consolidate the role of TNMD in tendon repair process. A comprehensive analysis of the TNMD gene and protein structure and its function in different stages of the tendon repair process is presented. In addition, the review addresses the potential therapeutic applications of TNMD, providing both a theoretical framework and an experimental foundation for the development of translational strategies in tendon and ligament clinical practice.

Irisin, an exercise-induced myokine, is known to be able to regulate bone metabolism. However, the underlying mechanisms regarding the effects of irisin on senile osteoporosis have not been fully elucidated. Here, we demonstrated that irisin can inhibit bone mass loss and bone microarchitecture alteration in senile osteoporosis mouse model. In addition, irisin has effects on bone remodeling that is in favor of bone formation. Remarkably, irisin induced autophagy in osteocytes demonstrated by increased LC3-positive osteocytes, and increased autophagy-related genes and proteins. In vitro analysis revealed that Irisin can prevent mitochondrial oxidative damage. Furthermore, irisin can obviously induce osteocyte mitophagy and increased phosphorylation of Ampk and Ulk1. Inhibition of Ampk signaling recapitulated the biological effect of irisin loss, accompanied by the markedly lower expression of Ulk1. Taken together, our findings show that irisin reduces age-related bone loss by inducing osteocyte mitophagy via Ampk-dependent activation of Ulk1.

OBJECTIVE:To analyze the effects of the angle between dynamic hip screw (DHS) and anti-rotation screw (AS) on vertically oriented femoral neck fractures (VOFNFs) and investigate the clinical results of them. METHODS:Eighteen synthetic femurs were simulated and divided into 3 groups. The angle between DHS and AS in anteroposterior-view was marked as α, and in lateral-view was marked as β, thus the total angle (TA) was defined as the summation of α and β. The groups were categorized as group A (TA ≤ 5°), B (5° < TA ≤ 10°), and C (TA > 10°), respectively. All samples were tested under incremental, cyclical loading, and loading to failure. In clinic, 80 consecutive VOFNFs in 78 patients were treated with DHS plus AS. The patients were divided into 2 groups, including 48 fractures in parallel group (TA ≤10°) and 32 in angular group (TA >10°). RESULTS:Group A and B survived during incremental and cyclical loading and endured longer than group C. Axial stiffness and failure loads were not different between group A and B, and greater than group C. Fracture gaps compressive stress was highest in group A, followed by group B and C. Forty-one fractures in parallel group and 23 in angular group healed at final follow-up. Nonunion and osteonecrosis occurred in 3 and 4 of parallel group, and 4 and 5 of angular group. CONCLUSION:The construction with TA ≤10° between DHS and AS showed superior biomechanical performance and clinical results than those with TA >10°.

Purpose Malunited distal radius fractures frequently occur in the older population, posing a dilemma in selecting ideal management for symptomatic patients. Radial corrective osteotomy (RCO) and the Sauv & eacute;-Kapandji procedure (SK) have been used to treat this challenging condition. However, it remains unknown which approach is better for the older population. The objective of this study was to compare the outcomes of RCO with those of SK for the treatment of symptomatic distal radius malunion in older adults. Methods Thirty-three patients aged >= 60 years, with malunited distal radius fractures, were randomized to be treated with either RCO or SK and followed for a minimum of 2 years. The primary evaluation parameter was grip strength, and secondary outcome parameters were surgical time, range of motion of the wrist, exercise-related wrist pain assessment using visual analog scale scores, radiographic results, patient-reported outcomes evaluated using the Disability of the Arm, Shoulder, and Hand (DASH), and Patient-Related Wrist Evaluation (PRWE) scores. Results The average follow-up duration was 36.7 +/- 10.2 months. The grip strength was significantly higher in the RCO group. The surgical time was shorter in the SK group than in the RCO group. The postoperative wrist range of motion and visual analog scale scores for exercise-related pain alleviation were similar in both groups. The ulnar variance decreased in both groups and was similar when compared with the postoperative images. The DASH and PRWE scores were similar between the RCO and SK groups. Conclusions Radial corrective osteotomy and SK surgeries have similar clinical and functional outcomes in patients aged >= 60 years. Grip strength is higher in the RCO group than in the SK group. However, the operating time to accomplish SK is shorter than RCO. (J Hand Surg Am. 2024;49(11):1089-1094. Copyright (c) 2024 by the American Society for Surgery of the Hand. All rights are reserved, including those for text and data mining, AI training, and similar technologies.) Type of study/level of evidence Therapeutic II.

Background Context: This study’s purpose was to evaluate the biomechanical performance of plate–nail and dual-plate fixation for the treatment of AO/OTA 41-C2 tibial plateau fractures. Methods: Twenty synthetic tibias were selected and randomly divided into a plate–nail group (n = 10) and a dual-plate group (n = 10). After the artificial tibias were osteotomized to simulate AO/OTA 41-C2 tibial plateau fractures in both groups, the plate–nail and the dual-plate methods, respectively, were used for fixation, and then axial compression loading, three-point bending, torsion, and axial failure tests were carried out. The data of each group were recorded and statistically analyzed. Results: In the axial compression test, the average stiffness of the plate–nail group was higher than that of the dual-plate group (p < 0.05). The displacement generated in the plate–nail group was significantly smaller than that in the dual-plate group (p < 0.05). In the resisting varus test, the stress of the plate–nail group was significantly higher than that of the dual-plate group (p < 0.05). In the resisting valgus test, the stress of the plate–nail group was slightly higher than that of the dual-plate group, but the difference was not statistically significant (p > 0.05). In the static torsion test, the load applied to the plate–nail group was smaller than that of the dual-plate group when rotated to 5° (p < 0.05). In the axial compression failure test, the average ultimate load of the plate–nail group was significantly higher than that of the dual-plate group (p < 0.05). Conclusion: The treatment of AO/OTA 41-C2 tibial plateau fractures with plate–nail fixation is superior to that with dual-plate fixation in resisting axial stress and preventing tibial varus deformity, while dual-plate fixation has better resisting torsional ability.

Purpose Malunited distal radius fractures frequently occur in the older population, posing a dilemma in selecting ideal management for symptomatic patients. Radial corrective osteotomy (RCO) and the Sauvé–Kapandji procedure (SK) have been used to treat this challenging condition. However, it remains unknown which approach is better for the older population. The objective of this study was to compare the outcomes of RCO with those of SK for the treatment of symptomatic distal radius malunion in older adults. Methods Thirty-three patients aged ≥60 years, with malunited distal radius fractures, were randomized to be treated with either RCO or SK and followed for a minimum of 2 years. The primary evaluation parameter was grip strength, and secondary outcome parameters were surgical time, range of motion of the wrist, exercise-related wrist pain assessment using visual analog scale scores, radiographic results, patient-reported outcomes evaluated using the Disability of the Arm, Shoulder, and Hand (DASH), and Patient-Related Wrist Evaluation (PRWE) scores. Results The average follow-up duration was 36.7 ± 10.2 months. The grip strength was significantly higher in the RCO group. The surgical time was shorter in the SK group than in the RCO group. The postoperative wrist range of motion and visual analog scale scores for exercise-related pain alleviation were similar in both groups. The ulnar variance decreased in both groups and was similar when compared with the postoperative images. The DASH and PRWE scores were similar between the RCO and SK groups. Conclusions Radial corrective osteotomy and SK surgeries have similar clinical and functional outcomes in patients aged ≥60 years. Grip strength is higher in the RCO group than in the SK group. However, the operating time to accomplish SK is shorter than RCO. Type of study/level of evidence Therapeutic II.

Objective:To explore the effectiveness and advantages of using Fastpass Scorpion suture passer to stitch the inferior capsulolabral complex in arthroscopic Bankart repair compared with traditional arthroscopic suture shuttle. Methods:The clinical data of 41 patients with Bankart lesion, who met the selection criteria and were admitted between August 2019 and October 2021, was retrospectively analyzed. Under arthroscopy, the inferior capsulolabral complex was stitched with Fastpass Scorpion suture passer in 27 patients (FS group) and with arthroscopic suture shuttle in 14 patients (ASS group). There was no significant difference between the two groups ( P>0.05) in gender, age, injured side, frequency of shoulder dislocation, time from first dislocation to operation, and preoperative Rowe score of shoulder. Taking successful suture and pull-tightening as the criteria for completion of repair, the number of patients that were repaired at 5∶00 to 6∶00 (<6:00) and 6∶00 to 7∶00 positions of the glenoid in the two groups was compared. The operation time, and the difference of Rowe shoulder score betwee pre- and post-operation, the occurrence of shoulder joint dislocation, the results of apprehension test, and the constituent ratio of recovery to the pre-injury movement level between the two groups at 1 year after operation. Results:Both groups completed the repair at 5∶00 to 6∶00 (<6∶00), and the constituent ratio of patients completed at 6∶00 to 7∶00 was significantly greater in the FS group than in the ASS group ( P<0.05). The operation time was significantly shorter in the FS group than in the ASS group ( P<0.05). All incisions in the two groups healed by first intention. All patients were followed up 12-36 months (mean, 19.1 months). No anchor displacement or neurovascular injury occurred during follow-up. Rowe score of shoulder in the two groups significantly improved at 1 year after operation than preoperative scores ( P<0.05), and there was no significant difference in the difference of Rowe shoulder score between pre- and post-operation between the two groups ( P>0.05). At 1 year after operation, no re-dislocation occurred, and there was no significant difference in the apprehension test and the constituent ratio of recovery to the pre-injury movement level between the two groups ( P>0.05). Conclusion:Compared with the arthroscopic suture shuttle, using Fastpass Scorpion suture passer to stitch the inferior capsulolabral complex in arthroscopic Bankart repair is more convenient, saves operation time, and has good effectiveness.

Objective To observe the clinical results and feasibility of corrective osteotomy combined with autogenous iliac bone graft for malunited distal radius fractures in the elderly.Methods A retrospective analysis on 22 cases of malunited distal radius fractures in the elderly from July 2020 to December 2021 was conducted.All patients were treated with corrective osteotomy combined with autogenous iliac bone graft and volar locking plate.Radiological parameters,range of motion of wrist,percentage of affected wrist grip strength in healthy side,VAS score,wrist DASH score,PRWE score and Gartland-Merley score were compared between before operation and at last follow-up.Results Twenty-two elderly patients were successfully followed up for at least 12 months.The incisions of all patients healed well without infection and neurovascular injury.At the end of follow-up,X-rays of 22 patients showed fracture union was achieved.The time of fracture union was 3-6 months,with an average 4.2 months.That the percentage of the affected side’s grip strength in the lateral side was（30.86±9.71）% preoperatively and（79.38±7.13）% at the last follow-up with statistically significant difference（P＜0.05）.There were significant differences in VAS score,DASH score,PRWE score,Gartland and Werley score,radiological parameters and range of motion wrist between before operation and at last follow-up（P＜0.05）.Conclusion Corrective osteotomy combined with autogenous iliac bone graft for malunited distal radius fractures in the elderly is safe and effective,and it can improve the grip strength and range of motion of wrist,and effectively relief patients’ clinical symptoms and improve their quality of life by reconstructing anatomical of the distal radius.

Background: The aim of the study was to investigate the effect of platelet-rich plasma (PRP) on subchondral bone marrow edema (BME) and the level of biomarkers in synovial fluid of the knee osteoarthritis.Methods: Eighty-one patients with symptomatic knee osteoarthritis were randomly divided into two groups according to the number of inpatients. Forty-five cases were trea-ted with intra-articular injection of PRP (PRP group), 36 cases were treated with sodium hyaluronate (SH group), and the clinical effects were evaluated using the Visual Analogue Scale (VAS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores. The changes of subchondral BME were assessed by magnetic res-onance imaging (MRI) before and after treatment. The levels of TNFa, IL-6, MCP-1, MMP-1, MMP-3, and MMP-9 in synovial fluid were also detected.Results: All the patients completed the corresponding treatment and were followed up for 12 months without serious complications. After the treatment, the VAS and WOMAC scores of the two groups were significantly decreased, and the difference was statistically signif-icant at different time points (P < 0.05). The VAS and WOMAC scores of the PRP group were better than those of the SH group (P < 0.05). MRI showed that the subchondral bone edema of the two groups were reduced in varying degrees, and the reduction was more noticeable in the PRP group (P < 0.05). The levels of TNFa, IL-6, MCP-1, MMP-1, MMP-3, and MMP-9 in two groups were decreased, and the difference was statistically significant at different time points (P < 0.05). However, the levels of TNFa, IL-6, MCP-1, MMP-1, MMP-3, and MMP-9 in the PRP group were significantly lower than those in the SH group (P < 0.05).Conclusions: Intra-articular injection of PRP can significantly reduce the subchondral BME and the level of biomarkers in synovial fluid of the symptomatic knee osteoarthritis.(c) 2023 Elsevier B.V. All rights reserved.

Bronchogenic cyst is a benign lesion with congenital dysplasia. Although the occurrence of this type of cyst is rare in the retroperitoneum, the presence of fluid-fluid levels is an even rarer phenomenon in bronchogenic cysts. Therefore, it can be easily misdiagnosed due to the lack of a universal guideline of specific imaging manifestations. The present report describes the case of a patient with a bronchogenic cyst with fluid-fluid levels whilst also performing a brief literature review to summarize the findings of previous reports on this condition. A 48-year-old male individual presented with severe lower back pain without any obvious causes. A CT scan revealed a low-density cystic mass of ~3x4x6 cm in the left front of the T12-L2 area, which originated from the left crus of the diaphragm. MRI revealed a fluid-fluid level in the cyst. Anterior thoracolumbar surgery was performed to completely resect the mass. During the surgery, it was confirmed that the cyst originated from the left crus of the diaphragm and the lesion was diagnosed to be a bronchogenic cyst by pathological analysis. The patient's symptoms improved after the surgery and no recurrence of the cyst was observed during the 3-year follow-up period. The presence of a fluid-fluid level in a retroperitoneal bronchogenic cyst is rare, particularly in the abdominal aorta and paravertebral regions, rendering it easily misdiagnosed. It may be associated with protein, hemorrhage and calcium-containing mucus deposition in the cysts. In the present study, a rare case of fluid-fluid level in bronchogenic cyst was reported and a literature review was provided.

目的 探讨关节镜下Bankart修复联合肩胛下肌增强术治疗肩胛盂骨缺损＜25％的慢性肩关节前向不稳的临床疗效.方法 回顾性分析自2017-01-2019-01采用关节镜下Bankart修复联合肩胛下肌增强术治疗的17例肩胛盂骨缺损＜25％的慢性肩关节前向不稳,比较两组术前以及术后6、12、24个月AESE评分、Rowe评分、前屈上举、外旋、内旋、外展90°外旋、外展90°内旋活动度.结果 17例均顺利完成手术并获得至少24个月的随访.均未出现神经损伤、再脱位等并发症.术后6、12、24个月AESE评分、Rowe评分较术前增加,差异有统计学意义(P＜0.05).术后6、12、24个月前屈上举、内旋、外展90°内旋活动度与术前比较差异无统计学意义(P＞0.05);外旋、外展90°外旋活动度较术前减小,差异有统计学意义(P＜0.05).末次随访时复查肩关节MRI片均未发现肩胛下肌损伤,压腹试验及熊抱试验均为阴性.结论 关节镜下Bankart修复联合肩胛下肌增强术治疗肩胛盂骨缺损＜25％的慢性肩关节前向不稳可以取得良好的疗效,术后患者肩关节外旋轻度受限,但无肩胛下肌损伤表现.

Background:Platelet-rich plasma (PRP) therapy is a new kind of biological therapy to retune the plasma concentrator into the patient's body for the treatment of osteoarthritis diseases. The present research aimsed to confirm the treatment effects of PRP against osteoarthritis injury and elucidate its potential mechanism via constructing a kind of cellular injury model of human synovial fibroblast cells (HSF cells) induced by synovial fluid from osteoarthritis patients.Materials and Methods:HSF cells wereas firstly treated with the different doses of synovial fluid from osteoarthritis patients, and evaluated for the cellular injury via cell morphology and MTT assay. And then, the protective effect of PRP against cellular injury were examined by cell morphology and MTT assay. Following, flow cytometry and western blot assay were employed to evaluate the effect of PRP on mitochondrial apoptosis. Finally, the effect of PRP on NF-κB pathway-associated inflammation wasere examined by Elisa ELISA assay and western blot.Results:The dilution ratio 1 : 5 of synovial fluid displayed an excellent injury effect against HSF cells and selected as the model condition. The data from cellular image and MTT assay showed that PRP with the doses 1 : 5 and 1 : 10 could alleviate the cellular mounts decrease in the damaged HSF cells. Flow cytometry, western blot, and Elisa ELISA assay displayed that PRP could relieve the cellular mitochondrial apoptosis and NF-κB pathway-associated inflammation in the damaged HSF cells.Conclusion:PRP might relieve HSF cells injury induced by synovial fluid from osteoarthritis patients through alleviating the mitochondrial apoptosis and NF-κB pathway-associated inflammation.

目的 采用网状Meta分析系统评价治疗肝细胞癌常用的射频消融(RFA)、经皮无水乙醇注射(PEI)、微波消融术(MWA)、激光消融术(LSA)、冷冻消融术(CRA)和PEI+RFA的临床价值.方法 通过检索PubMed、Embase、Clinical-trials.gov、万方数据库和CNKI数据库2017-12-20前收录的有关消融技术治疗肝细胞癌的随机对照试验,提取研究所需的数据,用Stata 14.0进行网状Meta分析.结果 最终纳入14项研究,共计1985例患者.累积排名曲线下面积(SUCRA)排序结果显示,在肿瘤完全消融率方面,由高到低排序依次为PEI+RFA(94.6％)、CRA(59.9％)、RFA(55.0％)、MWA(50.7％)、PEI(22.9％)和LSA(16.9％);在局部癌灶复发率方面,由低到高排序依次为CRA(93.2％)、PEI+RFA(67.1％)、MWA(60.5％)、RFA(41.8％)、LSA(31.9％)和PEI(5.5％).结论 RFA联合PEI的肿瘤完全消融率最高,CRA局部癌灶复发率最低.由于研究数据的不足和两两比较的研究数量不均衡,PEI+RFA和CRA的有效性还有待进一步研究.

BACKGROUND:Recently, the roles of ESR1 and ESR2 polymorphisms in osteoporosis have been extensively reported, with conflicting findings. Therefore, we performed this present study to evaluate the potential associations between ESR1 and ESR2 polymorphisms and osteoporosis risk.METHODOLOGY:All included literatures published up to April 2021 were identified by searching Pubmed, Embase, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI) and Wanfang databases. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated the associations using a fixed or random effects model.RESULTS:36 observational studies involving five gene polymorphisms (ESR1 PvuII, ESR1 XbaI, ESR1 G2014A, ESR2 AluI and ESR2 RsaI) covering 12507 cases and 18487 controls were included. The results of our meta-analysis demonstrated the variant A allele of ESR2 RsaI polymorphism might play a remarkable protective role in developing osteoporosis under all genetic models. However, no associations were observed between ESR1 PvuII, ESR1 XbaI, ESR1 G2014A and ESR2 AluI polymorphisms with the risk of osteoporosis under all genetic models.CONCLUSIONS:Our meta-analysis suggests that genetic polymorphism in ESR2 RsaI may lead to decreased risk for osteoporosis. Further larger studies are needed to confirm this conclusion.

目的 比较微创内固定系统与逆行髓内钉内固定治疗股骨远端骨折的临床疗效.方法 计算机检索PubMed、Embase、Cochrane、Web of Science、万方、中国知网数据库关于比较微创内固定系统与逆行髓内钉内固定治疗股骨远端骨折的文献,检索时间设置为2010-01-2021-05.观察指标为切口长度、手术时间、术中出血量、并发症发生率、膝关节功能优良率、骨折愈合时间.采用Review Manager 5.3软件进行Meta分析.结果 纳入10篇文献,6篇随机对照试验,4篇前瞻性病例对照研究.10篇文献中病例数共503例,其中微创内固定组245例,逆行髓内钉组258例.Meta分析结果显示,微创内固定组与逆行髓内钉组手术切口长度、手术时间、并发症发生率比较差异无统计学意义(P＞0.05);逆行髓内钉组术中出血量少于微创内固定组,骨折愈合时间比微创内固定组短,而微创内固定组术后膝关节功能优良率高于逆行髓内钉组,差异有统计学意义(P＜0.05).结论 微创内固定系统治疗股骨远端骨折术后膝关节功能优于逆行髓内钉内固定,而逆行髓内钉内固定治疗股骨远端骨折术中出血量更少且骨折愈合时间更短.

Objective The underlying mechanisms and molecular factors influencing intervertebral disc (IVD) homeostasis and degeneration remain clinically relevant. Tenomodulin (Tnmd) and chondromodulin (Chm1) are antiangiogenic transmembrane glycoproteins, with cleavable C-terminus, expressed by IVD cells that are implicated in the onset of degenerative processes. We evaluate the organ-level biomechanical impact of knocking out Tnmd alone, and Tnmd and Chm1, simultaneously. Design Caudal (c5-8) and lumbar vertebrae (L1-4) of skeletally mature male and female 9-month-old wildtype (WT), Tnmd knockout (Tnmd−/−), and Tnmd/Chm1 double knockout (Tnmd−/−/Chm−/−) mice were used ( n = 9-13 per group). Disc height index (DHI), histomorphological changes, and axial, torsional, creep, and failure biomechanical properties were evaluated. Differences were assessed by one-way ANOVA with post hoc Bonferroni-corrected comparisons ( P < 0.05). Results Tnmd−/−/Chm1−/− IVDs displayed increased DHI and histomorphological scores that indicated increased IVD degeneration compared to the WT and Tnmd−/− groups. Double knockout IVDs required significantly less torque and energy to initiate torsional failure. Creep parameters were comparable between all groups, except for the slow time constant, which indicated faster outward fluid flow. Tnmd−/− IVDs lost fluid faster than the WT group, and this effect was amplified in the double knockout IVDs. Conclusion Knocking out Tnmd and Chm1 affects IVD fluid flow and organ-level biomechanical function and therefore may play a role in contributing to IVD degeneration. Larger effects of the Tnmd and Chm1 double knockout mice compared to the Tnmd single mutant suggest that Chm1 may play a compensatory role in the Tnmd single mutant IVDs.

OBJECTIVE:To bring forward an arthroscopic classification of the popliteomeniscal fascicles of the lateral meniscus (PFLM) tears.DESIGN:Six fresh frozen knee joint samples of adult males were chosen, and the lateral meniscus at the popliteal hiatus region were measured to analyze their anatomic relationship. Patients who had received magnetic resonance imaging scan at knee joint before the surgery and diagnosed as PFLM tears by arthroscopy from April 2014 to October 2017 were selected. Data regarding the integrity of PFLM were prospectively recorded in a data registry. Tear morphology and treatment received were subsequently extracted by 2 independent reviewers from operative notes and arthroscopic surgical photos.RESULTS:The average length and thickness of the popliteal hiatus of the lateral meniscus were 2.09 ± 0.21 cm and 0.43 ± 0.08 cm, respectively. The average length of anterosuperior popliteomeniscal fascicle (APF) was 0.87 ± 0.18 cm, and the posterosuperior popliteomeniscal fascicle (PPF) was 0.72 ± 0.15 cm. A total of 36 PFLM tears in 36 patients were divided as type I (APF tear; n = 5, 13.9%), type II (PPF tear; n = 20, 55.6%), and type III (both APF and PPF tears; n = 11, 30.6%). All patients were treated with arthroscopic all-inside repair using a suture hook for the PFLM tears and follow-up for 21.1 months. All patients have done well with significantly improved Lysholm and International Knee Documentation Committee scores at the last follow-up relative to preoperative scores (P < 0.01).CONCLUSION:This study suggests to possibly classify the PFLM tears for clinical practice.