Orthopaedics & Traumatology-Surgery & Research最新文献

Background: Knee osteoarthritis (KOA) is a common degenerative disease impairing elderly mobility. Oxford Unicompartmental Knee Arthroplasty (OUKA) is effective for unicompartmental degenerative osteoarthritis, yet traditional intramedullary alignment methods may cause inaccuracies, compromising outcomes. The purpose of this study was to assess the safety and accuracy of a 3D-printed intramedullary femoral positioning guide in Oxford Unicompartmental Knee Arthroplasty (OUKA), with subgroup analysis by femoral mechanical-anatomical angle (FMA).

Methods: A prospective randomized controlled trial enrolled 120 patients with severe medial knee osteoarthritis undergoing OUKA. Patients were randomly divided into two groups: the experimental group (n = 60) used a 3D-printed intramedullary femoral positioning guide, while the control group (n = 60) employed traditional femoral intramedullary localization. The primary outcome measures were femoral component valgus/varus angle (FCVA) and femoral component posterior slope angle (FCPSA). Secondary outcomes included operative time, tourniquet time, and early postoperative complications. Stratified analyses were performed based on the femoral mechanical-anatomical angle (FMA) using cutoff values of < 5°, 5-7 °, and > 7°.

Results: Among the 119 patients with complete data (one lost to follow-up), no significant differences in FCVA (experimental: -0.63 ° [-2.46 ° to 1.60 °]; control: 2.31 ° [-4.17 ° to 3.12 °], P = 0.438) or FCPSA (9.72 ° [7.24 ° to 11.64 °] vs. 6.93 ° [3.96 ° to 15.70 °], P = 0.401) were observed overall. However, subgroups with FMA <5° or >7° showed significant improvements in FCVA (mean difference: -2.42 °, 95% CI: -3.12 ° to -1.72 °) and FCPSA (3.79 °, 95% CI: 2.45 ° to 5.13 °, both P < 0.05). No differences in operative time, complications, or functional scores were noted. Safety outcomes, including rates of deep vein thrombosis, infection, and prosthesis-related complications, were comparable between groups, with no severe adverse events reported.

Conclusion: 3D-printed guides improve prosthesis alignment in OUKA for patients with FMA <5° or >7° but not for FMA 5-7 °. Clinicians should consider patient-specific anatomical variations when deciding whether to use 3D-printed guides in OUKA.

Level of evidence: I; Randomized controlled trial.

Background: Knee osteoarthritis increasingly affects active adults under 65 years of age. As total and unicompartmental knee arthroplasty (TKA/UKA) become common treatments, return to work (RTW) emerges as a key milestone in recovery. While age, obesity, and comorbidities have been identified as predictors, the specific impact of professional occupation remains underexplored. This prospective study addresses this gap by investigating (1) how socio-professional category (SPC) influences the duration of sick leave after knee arthroplasty; and (2) whether physically demanding jobs; higher body mass index (BMI), age, and/ or other demographic or clinical factors are associated with prolonged sick leave.

Hypothesis: The authors hypothesized that the type of profession is the most significant predictor of extended sick leave following knee arthroplasty.

Methods: A prospective, single-center study was conducted involving 120 professionally active patients aged 18-65 years who underwent TKA or UKA between February 2020 and December 2023. Sociodemographic data, job classification (using PCS-ESE 2017), job physical demands, and clinical characteristics were collected. RTW status was evaluated at three months postoperatively, with an additional follow-up at four months for patients with extended sick leave (> 90 days). Univariate and multivariate logistic regression analyses were performed to identify predictors of prolonged sick leave (> 90 days).

Results: While patients in SPC-3 (executives and intellectual professions) and SPC-5 (employees) were significantly associated with prolonged sick leave in univariate analysis (OR = 0.35; 95% CI: 0.15-0.81; p = 0.014 and OR = 3.95; 95% CI: 1.73-8.98; p = 0.001, respectively), neither association was confirmed in multivariate analysis (SPC-3: OR = 1.52; 95% CI: 0.47-4.88; p = 0.484; SPC-5: OR = 2.41; 95% CI: 0.89-6.51; p = 0.0837). Secondly, physically demanding jobs strongly predicted extended sick leave, with nearly a fivefold increase in risk (OR = 4.58 95% CI:1.63-12.87; p = 0.0038). Thirdly, while a trend was observed for higher BMI to be associated with longer sick leave (OR = 1.09; 95% CI: 0.99-1.19; p = 0.060), no significant associations were found for sex, age, ASA score, length of hospital stay, discharge modality, or caregiver availability.

Conclusion: Physically demanding occupations and not professional status are the main factors delaying return to work after knee arthroplasty. In contrast, traditional demographic factors such as sex, BMI and ASA score appear less influential. These findings highlight the importance of integrating occupational context and modifiable risk factors into preoperative planning to facilitate earlier RTW and optimize patient recovery trajectories.

Level of evidence: II; prospective study.

Developmental dysplasia of the hip (DDH) is one of the most frequent pediatric disorders. Management of DDH is age-related. While an outpatient orthopedic treatment may be initiated during the neonatal period, open reduction with/out pelvic and/or femoral osteotomy is reserved for cases of failed closed reduction or late presentation. Open reduction aims at stable concentric hip reduction, with capsulorrhaphy enhancing stability. An S-shaped capsulotomy is proposed for 10 patients with an average follow-up 9.4 months, to enhance hip joint access and provide a more secure, double-layered capsulorrhaphy. LEVEL OF EVIDENCE: V; Technical note.

Background: As an emerging technology, functionally aligned robotic-assisted total knee arthroplasty (FA-RTKA) enables more precise osteotomy and prosthesis positioning through preoperative imaging modeling and intraoperative real-time navigation. Multiple studies have compared the clinical outcomes between FA-RTKA and mechanically aligned total knee arthroplasty (MA-TKA), yet the results remain inconsistent. It is necessary to conduct a meta-analysis to synthesize the existing evidence and investigate the differences in postoperative clinical outcomes between FA-RTKA and MA-TKA, thereby providing a more reliable basis for clinical decision-making.

Methods: We systematically searched four electronic databases (PubMed, Embase, Cochrane Library, and Web of Science). The inclusion criteria were controlled studies comparing the clinical outcomes between FA-RTKA and MA-TKA. The main outcomes were the Visual Analog Scale (VAS) score, Forgotten Joint Score (FJS), Knee Society Function Score (KSFS), Knee Society Knee Score (KSKS). Secondary outcome is the Range of Motion (ROM). All clinical outcomes were analyzed and evaluated using data from the final follow-up visit in each study.

Results: A total of 11 studies involving 1,666 patients subjected to TKA were included, with 833 patients in the FA-TKA group and 833 in the MA-TKA group. No significant difference was observed in the VAS score and ROM at the final follow-up between the two groups. Statistically significant differences were found in all other clinical outcomes. Specifically, significant improvements were noted in the FJS (MD: 15.79, 95% CI: 6.02-25.57, P = 0.002), KSKS (MD: 2.36, 95% CI: 1.33-3.39, P < 0.00001), and KSFS (MD: 7.94, 95% CI: 1.47-14.42, P = 0.002).

Conclusions: Compared to MA-TKA, FA-RTKA demonstrated superior outcomes in joint function, stability, and patients' subjective perception. In contrast, both techniques provided comparable pain relief.

Level of evidence: I.

Background: With the emergence of new alignment techniques such as kinematic alignment (KA) and functional alignment (FA), personalized joint line restoration has gained attention, yet its theoretical underpinnings remain underdeveloped. This study aims to investigate the impact of different joint line orientation angles (JLOAs) on knee compartment loads during total knee arthroplasty (TKA), thereby establishing a biomechanical tolerance range for JLOA and providing theoretical guidance for new alignment techniques.

Methods: We collected computed tomography (CT) data from three patients with severe knee osteoarthritis (KOA) and established standard mechanical alignment (MA) finite element models for each case. Keeping hip-knee-ankle angle (HKA) neutral, we constructed a series of JLOA models from -9 ° to +9 ° (Positive numbers represent varus, negative numbers represent valgus). Subsequently, the maximum stress on the polyethylene liner surface was calculated with ANSYS in three positions: two-legged stance, one-legged stance, and squat. Finally, a mathematical model of maximum stress trend was established through statistical analyses.

Results: In the three patients' models, during both the two-legged and one-legged standing positions, the maximum stress fluctuated smoothly from -3 ° to +4 °, while the maximum stress increased markedly when JLOA reached -4 ° and +5 °. In the squatting position, the stress increased markedly when it exceeded the -3 ° to +6 ° range. Quadratic regression analysis confirmed that all patient positions exhibited U-shaped curves (p < 0.05). T-tests comparing the three position tolerance ranges (-3°to +4 °) revealed that the two-legged standing position exhibited the highest stress increase ratio (46.01%, Cohen's d = 2.50) in the non-tolerance range. A three-way ANOVA confirmed that the tolerance range effect remained consistent across patients (p = 0.839), while stress levels varied significantly between patients (p < 0.001).

Conclusions: This in silico study demonstrated that the polyethylene liners maintain relative biomechanical homeostasis within the JLOA range of -3 ° to +4 °. It is recommended that the JLOA for personalized reconstruction can be controlled within this range, serving as biomechanical theoretical guidance for new alignment techniques.

Level of evidence: IV; biomechanical computational study.

Introduction: Total hip arthroplasty (THA) in obese patients (BMI ≥ 30 kg/m²) is technically more demanding and associated with a higher risk of postoperative morbidity. Its realization seems more complex by the direct anterior approach. The hypothesis was that muscular mass would have a stronger impact than BMI on intraoperative difficulty during anterior THA. The study objectives were; 1. To assess the influence of body composition and BMI on intraoperative difficulty, 2. To determine the influence of body composition on early complications (< 3 months) and short-term functional outcomes.

Methods: A total of 162 anterior approach THAs without traction table were included. Body composition (muscle and fat mass) was assessed preoperatively by bioelectrical impedance analysis of the operated limb and trunk. Subgroup analyses were performed according to BMI (< 30, 30-35, or ≥ 35) and muscle mass (threshold set at 67%). Intraoperative difficulty was evaluated based on operative time in minutes and total blood loss in mL, calculated using the OSTHEO formula. Perioperative complications, early complications (< 3 months), and 3-month functional outcomes (Oxford Hip Score and Forgotten Joint Score) were assessed.

Results: In univariate analysis, operative time (+19 min) and total blood loss (+615 mL) were significantly higher in patients with BMI ≥ 35 compared to those with BMI < 30 (p <  0.001). Operative time was also longer (+6 min) in muscular patients (≥ 67%) (p =  0.009), with no significant difference in total blood loss. No significant differences were observed in perioperative or early postoperative complications, nor in 3-month functional outcomes between obese/non-obese or muscular/non-muscular groups. In multivariate analysis, BMI and total muscle mass were independently associated with intraoperative difficulty: Operative time (min) = 22.2 + 0.25 × total muscle mass (kg) + 1.1 × BMI (R² = 0.24, p <  0.001) Total blood loss (mL) = -692.6 + 13.3 × total muscle mass (kg) + 31.1 × BMI (R² = 0.29, p <  0.001) CONCLUSION: BMI and total muscle mass are two preoperative factors associated with greater intraoperative difficulty, as reflected by increased operative time and total blood loss in anterior approach THA. These factors can be anticipated through a more detailed assessment of body composition. Despite the increased surgical complexity, they do not appear to be associated with a higher risk of early postoperative complications. In this cohort, muscle mass did not demonstrate a stronger impact than BMI on operative difficulty, contrary to the initial hypothesis.

Level of evidence: II; Prospective comparative study.