To assess the feasibility of a new technique for antegrade insertion of LC-II screws, guided solely by the obturator-outlet view. From September 2020 to September 2025, patients with pelvic and/or acetabular fractures involving disruption of the supra-acetabular corridor treated with antegrade insertion of a LC-II screw in our hospital were included in this study. The procedure of LC-II screw insertion was performed solely guided by the obturator-outlet view, referencing with two anatomical points, namely the anterior inferior iliac spine and a virtual anatomical point. Postoperative CT scans were carried out to assess whether the LC-II screws were placed correctly within the bony corridor. Peri- and postoperative complications were documented. Thirty-seven long, large-diameter (≥ 7 mm) LC-II screws were inserted in a total of 20 consecutive patients. The average length of these 37 screws was 115.8mm. The procedure was performed without any noted wound infections or related vascular, neurological, and visceral complications. Postoperative CT images confirmed that all 37 LC-II screws were correctly placed within the bony corridors, with no instances of screw penetration. All patients were followed up for an average of 19.1 months (range, 6.1- 37 months). No cases of screw loosening, breakage, or bone union failure were observed. The technique for antegrade insertion of LC-II screws, guided solely by the obturator-outlet view is a feasible surgical procedure. The virtual anatomical point has been shown to be a reliable anatomical landmark in our surgical procedure.

To compare the clinical efficacy and radiological outcomes of the far lateral approach of uni-portal non-coaxial spinal endoscopic surgery versus traditional percutaneous endoscopic transforaminal discectomy (PETD) for the treatment of L5/S1 foraminal stenosis with a high iliac crest. A retrospective analysis was conducted on 82 patients with L5/S1 foraminal stenosis and a high iliac crest treated at our hospital from June 2023 to June 2025. Patients were divided into a uni-portal non-coaxial spinal endoscopic surgery group (n = 42) and a PETD group (n = 40) based on the surgical procedure. Operative time, the fluoroscopy time estimated blood loss, length of hospital stay, and complication rates were recorded and compared between the two groups. Clinical outcomes were evaluated using the Visual Analogue Scale (VAS) for leg pain, the Oswestry Disability Index (ODI), and the modified MacNab criteria. Radiological assessments included postoperative foraminal area, facet joint preservation rate, and segmental stability. All patients were followed up for at least 12months. The uni-portal non-coaxial spinal endoscopic surgery group had a significantly shorter operative time (68.5 ± 12.3min vs. 92.6 ± 18.4min, P < 0.001) and significantly fewer fluoroscopy time (5.4 ± 1.5 vs. 15.8 ± 4.2, P < 0.001) compared to the PETD group. There were no significant differences between the two groups in estimated blood loss (42.5 ± 15.3mL vs. 40.2 ± 16.1mL, P 0.05) or length of hospital stay (3.2 ± 1.1days vs. 3.6 ± 1.4days, P 0.05). Both groups showed significant improvement in VAS and ODI scores at all postoperative time points compared to preoperative values (P < 0.05). At oneweek postoperatively, the uni-portal non-coaxial spinal endoscopic surgery group had noticeably better leg pain VAS scores than the PETD group (2.2 ± 0.7 vs. 3.3 ± 1.3, P < 0.01), while clinical outcomes were comparable between the two groups at three, six and 12months postoperatively (P 0.05). The excellent-to-good rate according to the modified MacNab criteria was 90.5% in the uni-portal non-coaxial spinal endoscopic surgery group and 87.5% in the PETD group (P 0.05). Radiologically, the uni-portal non-coaxial spinal endoscopic surgery group demonstrated a noticeably larger postoperative foraminal area (79.8 ± 13.2 mm2 vs. 63.5 ± 12.1 mm2, P < 0.001) and a noticeably higher facet joint preservation rate (93.5% vs. 75.8%, P < 0.01) compared to the PETD group. The complication rate was 7.1% in the uni-portal non-coaxial spinal endoscopic surgery group and 17.5% in the PETD group (P 0.05). Both the far lateral approach of uni-portal non-coaxial spinal endoscopic surgery and PETD are effective treatments for L5/S1 foraminal stenosis with a high iliac crest, yielding satisfactory clinical outcomes. Compared to PETD, uni-portal non-coaxial spinal endoscopic surgery offers advantages including shorter operative time, less fluoroscopy, more thorough foraminal decompression, and better preservation of the facet joint, making it a valuable and comparable alternative with additional perioperative benefits for managing pathologies in the L5/S1 region with a high iliac crest.

Antibiotic-loaded polymethylmethacrylate (PMMA) cement spacers are widely used in periprosthetic joint infection and chronic osteomyelitis. Manual prefabrication and sterilisation of non-commercial antibiotic-loaded cement may reduce operative time and cost; however, the effects of sterilisation and storage on antimicrobial efficacy remain unclear. Manually prefabricated PMMA cement containing vancomycin (2g or 4g) underwent formaldehyde gas sterilisation (FO) and storage for one, four or sevendays. Antibiotic elution was evaluated over 28days. Antimicrobial activity against Staphylococcus aureus ATCC 25923 was assessed using minimum inhibitory dilution (MID) testing at predefined time points. Given the small number of specimens per subgroup, all comparisons should be interpreted as preliminary and hypothesis-generating. FO sterilisation significantly reduced antimicrobial activity during the early elution phase. In the 4-g vancomycin group, Day 1 MID values were significantly higher in oneday storage sterilised specimens than in specimens stored for four or sevendays (1024µg/mL vs. 213µg/mL and 213µg/mL, respectively; P < 0.001). Differences persisted at early time points but were no longer significant during the sustained elution phase (Days 14-28; P > 0.05). Overall, sterilised cement containing 4g of vancomycin demonstrated higher MID values than 2g cement during the early and mid-elution phases (Days 1-14; P < 0.01). MID values in all sterilised specimens remained several-fold above inhibitory thresholds for S. aureus throughout the 28-day period. FO sterilisation transiently reduces vancomycin antimicrobial activity during the early elution phase (Days 1-7) but does not affect sustained antimicrobial efficacy compared with non-sterilised cement. Based on these findings, vancomycin-loaded PMMA cement containing 4g of antibiotic may be sterilised and stored for up to sevendays while maintaining MIC values several-fold above inhibitory thresholds for Staphylococcus aureus throughout the 28-day elution period.

Total hip arthroplasty (THA) is the standard treatment for hip osteoarthritis, yet its effects on lower limb alignment remain unclear. The coronal plane alignment of the knee (CPAK) classification system, widely used in knee surgery, has not been explored in THA. We investigated CPAK classifications in patients with hip osteoarthritis and examined alignment changes following THA. This retrospective cohort study analyzed 110 patients (113 hips) who underwent primary THA between January 2017 and July 2019. Full-length standing radiographs were obtained preoperatively and oneyear postoperatively. Measured parameters included the mechanical medial proximal tibial angle (MPTA), mechanical lateral distal femoral angle (LDFA), arithmetic hip-knee-ankle angle (aHKA), and joint line obliquity for CPAK classification. Horizontal and vertical alignments were assessed to determine hip centre position. Type II was the predominant CPAK type (47.8%) preoperatively, while types I and III were equally distributed (22.1% each). One year postoperatively, types I and II were equally prevalent (34.5% each), whereas type III decreased to 15%. LDFA and aHKA changed from 86.4 ± 2.2° to 87.9 ± 2.2° and from -0.2 ± 3.2° to -1.2 ± 3.2°, respectively, while MPTA remained unchanged. Hip center medialization was observed, with horizontal and vertical alignments changing from 43.6 ± 6.4mm to 34.7 ± 4.9mm and 30.2 ± 8.8mm to 24.5 ± 6.0mm. Japanese patients exhibit distinct CPAK patterns, with type II predominance. Post-THA alignment changes were characterized by increased LDFA and decreased aHKA due to hip center medialization, highlighting the importance of considering alignment changes during THA planning.

To clarify differences in hip-specific function, satisfaction, and patient preference between transposition osteotomy of the acetabulum (TOA) and contralateral total hip arthroplasty (THA) in the same patients with bilateral hip dysplasia. Among 689 patients who underwent TOA between 1998 and 2019, 32 patients who also underwent contralateral THA were included. Median age at surgery was 46 years for TOA and 50 years for THA (p = 0.008), and median follow-up was 14 and 12 years, respectively (p = 0.049). Postoperative patient-reported outcome measures included pain and satisfaction visual analogue scales (VAS), the Forgotten Joint Score-12 (FJS-12), and the Hip disability and Osteoarthritis Outcome Score (HOOS). Patients were also asked which hip they preferred. Preoperative modified Harris Hip Score (mHHS) was higher in TOA hips than in THA hips (64 vs. 43; p < 0.001), whereas the latest mHHS was lower in TOA hips (92 vs. 96; p = 0.007). Although pain VAS, FJS-12, and all HOOS subscales were comparable between TOA and THA, satisfaction VAS was higher in THA hips (98 vs. 93; p = 0.029). Fifteen patients (47%) preferred THA, nine (28%) reported no difference, and eight (25%) preferred TOA. The most common reason for preferring THA was less pain (10 of 15 patients, 67%). In middle-aged patients with bilateral hip dysplasia, TOA and contralateral THA yielded comparable functional outcomes; however, satisfaction was higher after THA, and 47% preferred THA. These findings may inform shared decision-making regarding joint-preserving surgery and arthroplasty.

Operating rooms contribute disproportionately to healthcare-related greenhouse gas emissions and waste generation. Total Hip Arthroplasty (THA) and Total Knee Arthroplasty (TKA) are high-volume procedures with increasing global incidence, yet pooled data on their environmental impact are lacking. A systematic review and pooled analysis were conducted in accordance with PRISMA guidelines (PROSPERO: CRD420261297449). PubMed, Embase, and Scopus were searched through October 31, 2025, for studies reporting total waste, recyclable waste, and carbon dioxide equivalent (CO₂e) emissions associated with primary THA and TKA. Seventeen studies, including 394 procedures, were included. Data extraction covered waste quantity, recyclable proportion, and carbon footprint. Random-effects models with inverse variance weighting were used to calculate pooled mean estimates. Standard deviations were estimated from reported ranges when not provided. Heterogeneity was assessed using I2 statistics. Pooled mean total waste per arthroplasty was 12.27kg (95% CI, 10.88-13.66). Recyclable waste averaged 1.97kg per procedure (95% CI, 1.64-2.31), representing 14.5% of total waste (95% CI, 11.99-17.02), and indicating substantial unrealized recycling potential. Carbon footprint estimates varied substantially by accounting methodology. Studies measuring waste-disposal emissions alone reported a pooled mean of 13.7kg CO₂e per case (95% CI, 11.32-16.08), whereas comprehensive life-cycle assessment (LCA) studies reported a pooled mean of 135.37kg CO₂e per case (95% CI, 74.91-195.83). Considerable inter-study heterogeneity reflected differences in waste segregation, recycling infrastructure, and carbon accounting methodologies. Primary THA and TKA generate substantial waste and carbon emissions, with low recycling rates across institutions. These findings provide benchmark data to inform sustainability initiatives, optimize resource use, and guide standardized environmental assessment frameworks in arthroplasty.

The optimal management of AO/OTA 33-C3 distal femoral fractures combined with symptomatic medial compartment knee osteoarthritis remains uncertain. This preliminary feasibility series explored whether metaphyseal comminution could be used as a "natural osteotomy" window to permit intentional valgus alignment correction during dual-plate fixation, while maintaining anatomical articular reconstruction and fracture stability. This retrospective preliminary feasibility series included 17 patients with AO/OTA 33-C3 distal femoral fractures complicated by Kellgren-Lawrence grade 3 or 4 medial compartment knee osteoarthritis. All patients underwent anatomical reconstruction of the articular surface, intentional mild valgus alignment correction using the metaphyseal comminuted zone as a "natural osteotomy," and medial-lateral dual-plate fixation. The primary feasibility outcomes included successful articular reconstruction, achievement and maintenance of planned valgus alignment, fracture union, and absence of early mechanical failure or reoperation. Operative time, intraoperative blood loss, articular step-off and gap, healing time, complications, mLDFA, and HKA angle were assessed. Pain, range of motion, Knee Society Score, and ambulatory status were evaluated as exploratory clinical outcomes. Mean operative time was 148.18 ± 10.01min and blood loss 351.18 ± 30.18mL. Anatomical articular reduction (step-off ≤ 2mm) was achieved in all patients, with mean step-off 0.97 ± 0.20mm and gap 0.98 ± 0.16mm. All fractures united (mean healing time 29.76 ± 3.42weeks), with no nonunion, implant failure, or reoperation within years. mLDFA changed from contralateral baseline 93.09° ± 0.65°to postoperative 85.03° ± 0.50°(P < 0.001); HKA changed from varus -9.12° ± 1.41°to valgus 2.47° ± 0.80°(P < 0.001). At final follow‑up, VAS pain score decreased from 7.47 ± 0.87 to 1.18 ± 0.39 (P < 0.001). KSS knee score increased from 34.12 ± 3.64 to 89.76 ± 3.21 (P < 0.001), and KSS function score from 43.82 ± 4.85 to 81.65 ± 2.80 (P < 0.001). Mean maximum knee flexion was 99.29° ± 4.22°at final follow‑up. Independent ambulation was achieved in 16 patients (94.1%). In this small single-center preliminary feasibility series, intentional valgus alignment correction using the metaphyseal comminuted zone as a "natural osteotomy" during dual-plate fixation was technically feasible in selected patients with AO/OTA 33-C3 distal femoral fractures and medial compartment knee osteoarthritis. This approach achieved fracture union, maintained coronal alignment, and showed favorable exploratory pain and functional outcomes at mid-term follow-up. These preliminary findings support this joint-preserving concept and warrant further validation in prospective comparative studies with longer follow-up.

This study aimed to evaluate the accuracy of two imageless navigation systems for restoring leg length change (LLC) and global offset change (GOC) in total hip arthroplasty (THA) using two-dimensional (2D) radiographic and three-dimensional computed tomography (3D CT)-based assessment methods. Patients undergoing primary cementless THA were divided into two groups based on the imageless navigation system used: a large-console group (n = 120) and a portable handheld group (n = 83). Intraoperative navigation measurements of the LLC and GOC were compared with values derived from preoperative and postoperative assessments, and absolute measurement errors were calculated. Accuracy was evaluated using 2D radiographic and 3D CT-based measurements. Between-system differences and discrepancies between 2 and 3D assessment methods were analyzed. Absolute LLC error in the large-console group was 2.7 ± 3.3mm on 2D radiographic evaluation and 2.5 ± 3.3mm on 3D CT-based evaluation, compared with 2.9 ± 2.7mm and 3.0 ± 2.8mm, respectively, in the portable handheld group. LLC error was significantly lower in the large-console group on 3D evaluation (p = 0.004). Absolute GOC error did not differ significantly between groups. No differences were observed between 2 and 3D evaluations for LLC, whereas most GOC-related parameters differed significantly between methods. Imageless navigation systems achieved favorable accuracy for LLC and GOC in THA. While radiographic assessment is sufficient for evaluating leg length, 3D CT-based evaluation provides a more consistent and less position-dependent assessment of global offset.

Osteoarthritis (OA) is now understood as a heterogeneous syndrome driven by diverse biological, biomechanical, metabolic, genetic, and molecular mechanisms. This variability explains differences in disease progression and treatment response, challenging the traditional "one-size-fits-all" approach. This review highlights OA phenotyping as a key step toward precision medicine, focusing on clinical, structural, and molecular classifications that inform individualized care. A narrative review was conducted using a non-systematic search of major databases and Osteoarthritis Research Society International sources (2010-2026). Evidence was thematically synthesized across clinical, imaging, and molecular domains to characterize OA phenotypes and their potential relevance to precision medicine. Multiple OA phenotypes were identified: inflammatory, metabolic, biomechanical, cartilage-subchondral, pain-sensitization, and aging/senescence. These exhibit distinct clinical features, risk factors, and therapeutic responses. Imaging-based phenotypes (e.g., inflammatory, meniscus-cartilage, subchondral bone, atrophic, hypertrophic) and molecular endotypes (low turnover, structural damage, systemic inflammation) further refine stratification. Pain-structure discordance is notable in sensitization phenotypes and may predict poorer surgical outcomes. Joint-specific variations and emerging genomic and epigenetic insights underscore disease complexity. Advances in imaging, biomarkers, and machine learning may enable earlier detection and patient clustering, though clinical application remains limited. Phenotype- and endotype-based classification represents a critical advancement toward precision OA management. Tailored interventions based on stratification hold promise for improving outcomes; however, clinical translation remains limited by overlapping phenotypes, lack of validated biomarkers, and inconsistent results from phenotype-driven trials. Wider clinical adoption requires standardized definitions, validation across joints, and integration of multimodal diagnostic tools into routine practice.

Septic arthritis (SA) of the native knee is a severe and increasingly prevalent condition, particularly among elderly and comorbid patients. When associated with end-stage degenerative joint disease, a two-stage total knee arthroplasty (TKA) with an antibiotic-loaded articulating spacer is commonly adopted. However, evidence directly comparing different spacer designs is limited. The aim of this study was to compare the clinical and functional outcomes of two two-stage strategies: a preformed cement articulating spacer and a Hofmann-type metal-on-polyethylene articulating spacer. We retrospectively reviewed 15 consecutive patients treated between June 2022 and December 2024 at a tertiary referralcentre. Inclusion criteria were native knee SA with end-stage arthritis managed with planned two-stage TKA and minimum 12-month follow-up. Seven patients received a Hofmann spacer and eight a preformed cement spacer. The primary endpoint was septic failure, defined as recurrent infection requiring surgical intervention; secondary endpoints included functional outcomes (Knee Society Score [KSS], Oxford Knee Score [OKS], Forgotten Joint Score [FJS]), pain (VAS), and range of motion (ROM) during the interstage period and after reimplantation. Mean follow-up was 24.2months. Infection eradication was comparable between groups, with one reinfection (6.7%) occurring in the cement spacer group (p = 1). During the interstage period, the Hofmann group demonstrated significantly superior KSS, OKS, FJS, VAS, and ROM (p = 0.001). After reimplantation, functional outcomes remained significantly better in the Hofmann group, with greater ROM and higher patient-reported scores. Two patients in the Hofmann group elected spacer retention due to satisfactory function. Both strategies achieved effective infection control. However, the Hofmann articulating spacer provided superior functional recovery without compromising septic eradication, supporting its use in selected patients with native septic knee arthritis and advanced degeneration.