Coronal tibiofemoral subluxation (CTFS) is frequently observed in patients with medial knee osteoarthritis; however, its clinical relevance and the acceptable degree of CTFS when considering unicompartmental knee arthroplasty (UKA) remain unclear. This study aimed to determine whether preoperative CTFS influences short-term postoperative clinical outcomes in patients with anteromedial osteoarthritis (AMOA) undergoing medial UKA. In this retrospective cohort study, 457 consecutive knees with AMOA who underwent mobile-bearing UKA performed at a single center between August 2016 and May 2023 were analyzed. CTFS, defined as medial translation of the femur relative to the tibia, was measured on preoperative weight-bearing anteroposterior radiographs and expressed as the percentage of tibial plateau width. Patients were categorized into mild (0–5
Day-case hip and knee arthroplasty can reduce bed occupancy and improve cost-effectiveness, which is crucial for addressing the increasing demand among hip and knee osteoarthritis patients. This study investigated how different arthroplasty center setups were associated with the implementation and day-of-surgery (DOS) discharge rates of a standardized day-case setup. We included unilateral primary hip and knee arthroplasty patients from seven fast-track arthroplasty centers, all implementing a standardized day-case setup in September 2022 with identical eligibility and discharge criteria. Centers were categorized as: Satellite Arthroplasty Centers (SACs): Only primary arthroplasties, separate logistics. Elective Arthroplasty Centers (EACs): Complex primaries, revisions, separate logistics. Arthroplasty Unit Orthopedic Departments (AUOs): Primary and revision procedures, integrated into a general orthopedic department. We compared DOS discharge rates from September 2022 to September 2023 with a baseline period (July 2019–December 2019) using crude percentages. We compared the DOS discharge rate for day-case-eligible patients in study period between the center types using mixed effects models. We included 6718 patients (1357 SAC, 4309 EAC, 1052 AUO) during the study period and 3974 in the baseline period. DOS discharge rates increased post-implementation across all centers (SAC: 3.9
Pelvic discontinuity is a rare but challenging condition in revision hip arthroplasty. Traditional cage-based reconstruction techniques often rely solely on mechanical fixation and may be associated with implant migration, loosening, and mechanical failure. Alternative strategies aimed at restoring pelvic continuity and achieving biological fixation may improve construct stability and clinical outcomes. This retrospective study included 19 patients with intraoperatively confirmed pelvic discontinuity who underwent revision total hip arthroplasty between 2014 and 2024. Patients were divided into three groups according to the reconstruction technique used: Group 1 (n = 8) underwent anti-protrusio cage reconstruction alone, Group 2 (n = 6) received additional anterior quadrilateral surface plating prior to cage implantation, and Group 3 (n = 5) underwent restoration of pelvic continuity through anterior and posterior column fixation followed by implantation of a porous-coated primary acetabular cup. Clinical and radiological outcomes were assessed with a minimum follow-up of 2 years, including complications, loosening, reoperation, and reoperation-free survival. Nineteen patients (mean age 71.2 years) with intraoperatively confirmed pelvic discontinuity were included. Aseptic loosening rates differed significantly among the three groups (P = 0.039), occurring in 50
Monteggia-like lesions are rare but complex elbow injuries involving fractures of both the proximal ulna and the radial head. While the influence of ulnar alignment and soft tissue integrity on radial head stability has been extensively studied, the effect of radial head integrity on the stability of ulnar fixation remains poorly understood. Given the high rates of nonunion and revision surgery after proximal ulna fractures, improved understanding of forearm biomechanics in these combined injuries is highly clinically relevant as it influences the surgical strategy in primary care of these injuries. Accordingly, this study aimed to evaluate the biomechanical impact of radial head resection and radial head arthroplasty on forearm stiffness in a simulated Monteggia-like injury model. We hypothesized that radial head resection would reduce construct stiffness compared with both the native state and radial head arthroplasty, and that arthroplasty would partially restore stiffness toward native levels Eight fresh-frozen human cadaveric elbow specimens were biomechanically tested under axial loading. After baseline testing in the native state, a standardized segmental comminution model was created and stabilized using locking plate osteosynthesis. Sequential testing was then performed after radial head resection and after implantation of a modular radial head prosthesis. Specimens were loaded cyclically up to 450 N for 1,000 cycles with the elbow positioned at 30° of flexion. Construct stiffness was calculated and compared between testing conditions. Mean construct stiffness in the native state was 49.3 ± 4.29 N/mm and decreased significantly after creation and fixation of the ulnar defect (36.05 ± 6.71 N/mm). Radial head resection resulted in a further significant reduction in stiffness (25.83 ± 6.65 N/mm). Following radial head arthroplasty, stiffness increased to 33.8 ± 7.89 N/mm, representing a significant improvement compared with the resection state (p ≤ 0.0026). No significant difference was observed between stiffness after prosthesis implantation and the condition with intact radial head and stabilized ulna. Radial head integrity significantly contributes to forearm stiffness in Monteggia-like lesions. Radial head arthroplasty partially restores biomechanical stability after resection and may alter load distribution in a manner that could be relevant for fixation durability. These findings support the need to address the radial column to optimize stability in complex elbow injuries. Biomechanical study
Floating elbow is a rare injury type in pediatric fractures. This study compared the differences in injury mechanisms, treatment modalities, complications and prognosis between floating elbow injury and supracondylar humerus fractures (SHF) in children in a surgically treated cohort. The retrospective analysis included patients with floating elbow and SHF treated at our hospital between May 2016 and May 2023. Sex, age, body mass index (BMI), mechanism of injury, affected limb, fracture displacement, presence of neurovascularinjury, type of injury, Gartland classification, and acute compartment syndrome (ACS) were analyzed. Elbow function was evaluated using the Mayo Elbow Performance Score (MEPS). ACS was defined by clinical criteria including pain, paresthesia, and/or compartment pressure > 30 mmHg. A total of 113 children were enrolled, including 27 in the floating elbow group (22 males, 5 females, median age 8 years [IQR 6–11 years]), and 86 in the SHF group (58 males, 28 females, median age 8 years [IQR 5–10 years]). Mechanism of injury (p = 0.001), fracture type (p = 0.003), and preoperative nerve injury (p = 0.001) differed significantly between the two groups. ACS incidence differed significantly between open and closed fractures in the floating elbow group (p = 0.028); however, this finding is based on a small number of events. In this surgically treated cohort, we did not detect statistically significant differences in elbow function outcomes between children with floating elbow and those with isolated SHF. Open fractures were associated with a higher incidence of ACS in the floating elbow group compared with closed fractures, although the number of events was small (p = 0.028). Larger studies are needed to confirm equivalence or identify clinically meaningful differences. III.
