Journal of Orthopaedic Surgery and Research最新文献

Background: Screw cut-out remains a major mechanical complication after proximal femoral nailing (PFN) for intertrochanteric fractures. Traditional predictors such as tip-apex distance (TAD) and reduction quality do not account for individual femoral anatomy. This study aimed to determine whether deviation from the contralateral collodiaphyseal (CCD) angle (|Δ angle|) independently predicts screw cut-out after PFN.

Methods: A total of 354 patients (mean age 77.6 ± 12.0 years; 58% female) treated with PFN between 2015 and 2020 were retrospectively analyzed. Radiographic parameters included TAD and the absolute difference between postoperative and contralateral collodiaphyseal (CCD) angles (|Δ angle|), representing patient-specific alignment. Functional outcomes were assessed using the Harris Hip Score, Barthel Index, and time to full weight bearing. Univariate and multivariable logistic regression analyses were performed to identify independent predictors of screw cut-out.

Results: Screw cut-out occurred in 56 patients (15.8%) and was associated with larger TAD, greater |Δ angle| deviation, and poorer reduction quality (all p < 0.01). In multivariable analysis, TAD, |Δ angle|, and reduction quality independently predicted cut-out. Patients with cut-out exhibited lower functional scores and delayed weight bearing, indicating substantial impairment in postoperative recovery.

Conclusion: Patient-specific anatomical alignment, along with TAD and reduction quality, independently predicts screw cut-out. Deviations ≥ 9° from native CCD alignment increase mechanical failure risk and delay functional recovery.

Background: Understanding the microstructural basis of anterior cruciate ligament (ACL) mechanics is important for advancing reconstruction strategies and rehabilitation. Histological studies indicate that collagen and elastin are distributed in a region-specific manner within the ligament, but such heterogeneity has rarely been incorporated into computational models. Finite element (FE) simulations are widely applied in ligament biomechanics, yet their validation against clinically used tools such as the Lachman test with KT2000 arthrometry remains limited. This study aimed to investigate how regional collagen-elastin variations affect ligament mechanics, whether histology-informed models provide improved agreement with experimental data, and how closely such models align with clinical assessment.

Methods: Porcine ACLs were selected as surrogates for the human ligament due to their structural similarity. Regional collagen and elastin distributions were quantified using histological imaging and integrated into a crosslinked collagen-elastin fiber network model. FE analyses were performed under tensile, shear, and torsional loading. Model predictions were compared with uniaxial tensile testing of ACL specimens and with force-displacement curves obtained from KT2000 arthrometry during Lachman testing. Simulations were conducted at both millimeter and micrometer scales to assess multi-scale applicability.

Results: The histology-informed fiber model reproduced ligament stiffness more consistently than a uniform sheet representation, particularly under tensile loading. Its stiffness characteristics showed partial agreement with experimental uniaxial data and with KT2000 arthrometer measurements in normal and injured knees. Comparable outcomes across different model scales suggested that the framework is adaptable to multi-scale analyses.

Conclusion: This study highlights the contribution of region-specific elastin distribution to ACL mechanical behavior and demonstrates that histology-informed FE models may improve biological relevance compared with uniform representations. While still preliminary, the partial alignment with both experimental and clinical measurements suggests that such models may provide a useful foundation for bridging microstructural mechanics and joint-level function. With further refinement, this approach could support individualized planning, rehabilitation monitoring, and the design of biomimetic grafts.

Introduction: The critical shoulder angle (CSA), a radiographic measure reflecting the relationship between glenoid inclination and lateral acromial coverage, has garnered increased attention for its potential influence on shoulder arthroplasty outcomes. Despite its significance, the impact of CSA on shoulder arthroplasty outcomes remains uncertain, as conflicting evidence persists in the literature. The purpose of this systematic review was to conduct a comprehensive analysis of the available literature, focusing on the functional outcomes and complications associated with CSA in the context of shoulder arthroplasty.

Materials and methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.The English-language articles were screened from databases such as PubMed, EMBASE, the Web of Science, and the Cochrane Library Database. Studies involving patients who underwent shoulder arthroplasty and evaluated the influence of CSA on complications, clinical scores, and range of motion (ROM) were included. The data were independently extracted by two authors, and evidence quality and bias risk were assessed collectively.

Results: Nine studies were included-six cohort studies, one case series, and two case-control studies. When a meta-analysis was not conducted, a consistent trend emerged. A higher CSA was linked to an increased risk of revision surgery after shoulder arthroplasty, primarily due to complications such as prosthetic loosening, glenoid lucency, and secondary rotator cuff failure. However, no substantial correlation was found between the CSA and postoperative clinical score or ROM.

Conclusions: A higher CSA correlates with an increased revision rate following shoulder arthroplasty, primarily due to complications such as prosthetic loosening. However, the CSA was not significantly correlated with postoperative clinical score or ROM. This finding underscores the value of the CSA as a predictive factor for revision risk while emphasizing its limited impact on clinical outcomes and shoulder joint ROM.

Level of evidence: Level IV; Systematic Review.

Background: Glucagon-like peptide-2 (GLP-2) has been demonstrated to stimulate bone formation and increase bone mass. Conversely, aberrant expression of fibroblast growth factor 23 (FGF23), a crucial bone-derived hormone that regulates phosphate metabolism and mineralization, is implicated in the pathogenesis of osteoporosis. This study aimed to elucidate the mechanisms by which GLP-2 ameliorates postmenopausal osteoporosis, focusing on whether it exerts bone-protective effects through downregulation of FGF23 expression via the PI3K/AKT/FOXO1 signalling pathway.

Methods: An ovariectomized (OVX) mouse model was established to mimic postmenopausal osteoporosis. Mice were treated with GLP-2, the PI3K inhibitor LY294002, or a combination of both. The bone mineral density (BMD) of the femur and lumbar spine, trabecular microarchitecture (BV/TV, Tb.N, Tb.Sp, Tb.Pf), and expression of Runx2 and FGF23 were assessed. RNA sequencing and KEGG pathway enrichment analyses revealed key signalling pathways. In vitro, MC3T3-E1 osteoblasts were subjected to GLP-2R overexpression or knockdown, as well as PI3K/AKT and FOXO1 modulation, to explore the underlying mechanisms.

Results: Compared with the sham, control mice, the OVX mice exhibited significantly lower femoral and lumbar BMD (P < 0.01), lower BV/TV and Tb.N, and greater Tb.Sp and Tb.Pf (P < 0.01). Runx2 expression was downregulated, whereas FGF23 levels in bone and serum were markedly elevated (P < 0.01). GLP-2 treatment significantly increased the BMD (femur + 18%, lumbar + 22%), increased the BV/TV and Tb.N, reduced Tb.Sp and Tb.Pf (all P < 0.05), upregulated Runx2 expression, and downregulated FGF23 expression. RNA-seq revealed enrichment of the PI3K/AKT pathway in the differentially expressed genes. LY294002 partially reversed the effects of GLP-2, lowering the BV/TV by 12% and increasing the level of FGF23 by 30% (P < 0.05). In MC3T3-E1 cells, GLP-2 increased p-AKT and p-FOXO1 levels (P < 0.01) and decreased FGF23 mRNA and protein levels (40% reduction, P < 0.01); these effects were abolished by PI3K/AKT inhibition. Inhibition of FOXO1 can reduce FGF23 expression, whereas the overexpression of FOXO1 leads to an increase in FGF23 expression, suggesting that the transcription of the FGF23 gene requires the participation of FOXO1.

Conclusions: GLP-2 ameliorates postmenopausal osteoporosis by activating the PI3K/AKT/FOXO1 pathway in osteoblasts, leading to FGF23 downregulation. These findings provide novel molecular insights and potential therapeutic targets for the use of GLP-2 in osteoporosis management.

Background: Poor posture and related musculoskeletal conditions represent a growing global health concern. Conventional postural assessment methods are often subjective, intermittent, and insufficient for accurate, continuous monitoring. Advances in artificial intelligence (AI), particularly in computer vision and human pose estimation (HPE), have introduced new possibilities for objective and real-time postural analysis.

Main body: This critical review synthesizes and evaluates current developments in AI technologies for postural management. The review draws on recent literature from computer science, bioengineering, and clinical research, focusing on studies from the past decade that explore the use of AI and HPE in the detection, monitoring, and correction of human posture. AI-based HPE models demonstrate high precision in identifying anatomical landmarks and quantifying postural parameters, offering a robust alternative to traditional assessment methods. Applications are expanding beyond laboratory environments to practical contexts such as ergonomic risk evaluation and sports performance analysis. In addition, AI-driven systems that deliver real-time feedback and support tele-rehabilitation are enhancing user engagement and enabling personalized interventions. Despite these advancements, the field faces several challenges. Evidence from large-scale clinical trials remains limited, and the generalizability of existing models across diverse populations and real-world conditions is uncertain. Concerns related to usability, data privacy, and integration within healthcare systems also pose significant barriers to clinical translation.

Conclusion: AI holds considerable potential to transform postural management through continuous, objective, and accessible assessment and intervention. To fully realize this potential, future work must extend beyond technical innovation to include rigorous clinical validation, user-centered design, and the establishment of ethical and regulatory frameworks that ensure safe, effective, and equitable implementation.

Background: To determine whether an integrated dual-lag-screw (IDLS) cephalomedullary nail (CMN) confers superior clinical and mechanical outcomes compared with single-lag-screw (SLS) designs in the fixation of intertrochanteric femoral fractures.

Methods: Seven databases (MEDLINE, Embase, Cochrane CENTRAL, Web of Science, Google Scholar, ClinicalTrials.gov) were searched from inception through 20 January 2025 following PRISMA guidelines. Randomized trials and comparative observational studies of adult intertrochanteric or subtrochanteric extension fractures treated with IDLS versus SLS nailing and ≥ 6 months follow-up were eligible. Twenty-nine studies met all criteria. Three reviewers independently screened studies, extracted data, and graded quality (ROB-2 for randomized controlled trials, MINORS for non-randomized studies). Random-effects meta-analysis produced pooled odds ratios (OR) for binary outcomes; heterogeneity was assessed with I². Publication bias was explored with funnel plots, trim-and-fill, and Egger's test.

Results: The 29 studies encompassed over 20,000 fractures. Compared with SLS nails, IDLS fixation was associated with significantly fewer implant-related complications (OR 0.55, P = .01), instances of lag-screw cut-out (OR 0.44, P = .016), and cases of lateral hip or thigh pain (OR 0.50, P < .01). In the unstable-fracture subgroup, IDLS nails similarly showed lower odds of implant-related complications (OR 0.38, P < .001), revision surgeries (OR 0.37, P = .005), mechanical failure (OR = 0.19, P < .001), cut-out (OR = 0.19, P < .001) and post-operative hip/thigh pain (OR = 0.47, P < .006) compared to SLS nails. No significant evidence of publication bias was detected. Operative time, blood loss, union rate, and 1-year Harris Hip Score were comparable between constructs.

Conclusions: IDLS CMNs demonstrated markedly lower rates of mechanical failure, revision surgery, and lateral hip/thigh pain, especially in unstable intertrochanteric fracture patterns. These findings support preferential use of IDLS implants in geriatric fragility hip fractures.

Level of evidence: Level IV Therapeutic.

Objective: This study aimed to quantify and compare the learning curves of percutaneous endoscopic interlaminar discectomy (PEID) and unilateral biportal endoscopic discectomy (UBED) for lumbar disc herniation (LDH), using operative time and clinical outcomes as primary metrics.

Methods: This study retrospectively reviewed 158 consecutive patients with lumbar disc herniation (LDH) who underwent endoscopic lumbar discectomy from 2022 to 2024. The patients were categorized into two groups: PEID group (n = 93) and UBED group (n = 65). The learning curve for each technique was evaluated using cumulative sum (CUSUM) analysis. Surgical failure was defined as the occurrence of either complications or a lack of symptom relief. Patient and surgical variables were then compared across the distinct phases of the learning curve.

Results: CUSUM analysis demonstrated distinct learning curves for PEID and UBED, with identified cut-off points at 45 and 31 cases, respectively. Upon reaching the mastery phase, the mean operative time decreased significantly by approximately 17 min for PEID and 18 min for UBED. The surgical failure rate did not differ significantly between the initial and mastery phases in either group. Notably, both techniques resulted in significant postoperative improvements in clinical outcomes, as evidenced by the Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), and Japanese Orthopaedic Association (JOA) scores at the final follow-up compared to preoperative baselines.

Conclusion: Both PEID and UBED demonstrated comparable effectiveness and low complication rates in the treatment of LDH. Notably, the learning curve analysis revealed that achieving procedural proficiency required 45 cases for PEID, compared to 31 cases for UBED.

Purpose: This study aimed to identify radiographic and demographic predictors influencing the intraoperative decision for cemented versus cementless humeral fixation in patients ≤ 80 years undergoing short-stem reverse shoulder arthroplasty (RSA).

Methods: A retrospective analysis was conducted on RSA cases between 02/2019 and 10/2024. Patients ≤ 80 years were stratified into Group A (cementless fixation; n = 209) or Group B (cemented fixation; n = 58) based on intraoperative assessment of trial stem stability and bone quality. Preoperative variables included age, sex, body mass index (BMI), American Society of Anesthesiologists score (ASA), diagnosis, and radiographic parameters such as cortical bone thickness gauge (CBTg), average cortical thickness (CBTavg), acromiohumeral distance (AHD), and Hamada and Walch classifications. Multivariate logistic regression including age, sex, CBTavg, CBTg, and diagnosis was performed to identify independent predictors of cemented fixation.

Results: Patients in the cemented group were significantly older (74.0 ± 4.2 vs. 70.0 ± 6.1 years; p < 0.05) and more often female (81% vs. 61%; p < 0.05). Cortical bone measurements were significantly lower in the cemented group (CBTg: 0.25 ± 0.06 vs. 0.27 ± 0.06; CBTavg: 5.15 mm ± 1.23 mm vs. 6.42 mm ± 1.43 mm; both p < 0.05). Multivariate analysis identified increasing age (OR: 1.1; p < 0.05), female sex (OR: 2.8; p < 0.05), and reduced CBTavg (OR: 0.6; p < 0.05) as independent predictors of cemented fixation. Other variables such as BMI, ASA score, AHD, and CBTg did not show significant associations with fixation type.

Conclusion: Among all evaluated factors, lower CBTavg was the strongest independent predictor for the use of cemented humeral fixation in short-stem RSA. Its integration into preoperative planning may assist surgical decision-making and improve consistency in fixation strategy.

Study design: Level IV; retrospective case series.

Background: Marijuana use is rising in the United States, yet its impact on perioperative outcomes remains poorly understood, particularly in orthopaedic trauma where cessation is often not feasible. This study evaluates the risks associated with cannabis and nicotine use in patients undergoing fixation of upper extremity fractures.

Methods: We performed a retrospective analysis of adult trauma patients with upper extremity fractures (2015-2023) identified using CPT codes for surgical fixation in the TriNetX database. Four cohorts were defined: cannabis-only users (n = 801), nicotine-only users (n = 14,310), concurrent users (n = 901), and non-users matched 1:1 to each exposure cohort. Propensity score matching was applied to each pairwise comparison. Primary outcomes were surgical and medical complications; secondary outcomes included new postoperative psychosocial diagnoses (anxiety, depression, opioid use disorder, and chronic pain) and coagulation parameters. Binary outcomes were compared using absolute risk differences, risk ratios, odds ratios, and 95% confidence intervals; continuous outcomes with independent t-tests, all assessed within 1 year following surgery.

Results: Cannabis-only users had significantly higher rates of implant-related infection, reoperation, readmission, depression, and anxiety compared with non-users (p < 0.05). Nicotine-only users demonstrated higher odds ratios in most overlapping outcomes and showed significantly elevated rates across a broader range of complications, including superficial and deep infection, nonunion or malunion, wound dehiscence, pneumonia, chronic pain, mortality, and psychosocial complications. Concurrent users did not demonstrate additive risk compared with cannabis-only users.

Conclusion: Cannabis and nicotine use were independently associated with increased postoperative complications following fixation of upper extremity fractures compared with matched non-user controls. The absence of statistically significant additive effects may reflect limited power to detect modest interactions, overlapping biological mechanisms, or a true absence of synergy. These findings support standardized screening, risk stratification, and targeted perioperative strategies, including extended antibiotic prophylaxis and integrated psychosocial support, to reduce complications in this at-risk population.