Analysis of biomechanical gait parameters in patients after total hip replacement operated via anterolateral approach depending on size of the femoral head implant: retrospective matched-cohort study.

INTRODUCTION: Total hip replacement (THR) is considered one of the most effective medical procedures in treatment of osteoarthritis. Since its introduction, there has been a worldwide debate over proper implant selection in terms of size, bearing type and shape. Following study was designed to assess the importance of femoral head size in long-term follow-up. MATERIALS AND METHODS: A cohort of 30 patients with primary end stage osteoarthritis who underwent total hip replacement was analysed retrospectively. A homogenous group was chosen with no major differences in BMI. Patients' gait parameters were measured in a biomechanics laboratory using the 3D BTS Smart system. WOMAC and VAS questionnaires were used to assess patient reported outcome. RESULTS: The subgroup with larger implant head size had several outcomes significantly superior to the subgroup with standard head size and non-inferior to healthy hips. Following variables were measured during this study: time of support phase, time of swing phase, double support time, walking hip extension angle. CONCLUSIONS: Use of larger sized femoral heads during THR gives better results in terms of gait pattern. Since restoring the gait pattern is one of the aspects of rehabilitation and returning to daily activities it seems to be an important observation.

The Direct Anterior Approach to Primary Total Hip Replacement: Radiological Analysis in Comparison to Other Approaches.

Total hip arthroplasty (THA) is currently considered the most effective treatment for end-stage hip osteoarthritis (OA). The surgery can be performed via a number of different approaches, including direct anterior (DAA; Smith-Petersen; Hueter), anterolateral (ALA; Watson-Jones), direct lateral (LA; Bauer), posterior (PA; Kocher-Langenbeck), and posterolateral (PLA). There is still a dispute over the optimal technique. The aim of this systematic review was to assess how different surgical approaches toward a THA influence the prosthesis elements' positioning. We conducted a literature search of Scopus, ScienceDirect, PubMed, Embase, and The Cochrane Library. We evaluated studies in terms of the first author's name, country, publication year, type of surgical approach being compared to the direct anterior approach, any significant differences at baseline, sample size, and radiographic analysis. A subanalysis of each approach in comparison to the DAA revealed differences in terms of all analyzed implant positioning radiographic parameters. There is still an insufficient number of randomized controlled studies that include radiological analyses comparing THRs (total hip replacements) performed using DAA with other approaches. Implant placement is a crucial step during a THR and surgeons must be aware that the approach they use might impact their judgment on angles and spaces inside the joint and thus alter the implant positioning.

Genetic Predisposition for Osteoporosis and Fractures in Postmenopausal Women.

Osteoporosis is a disease with complex etiology where the genetic factors may account for as much as 50-85% of the risk of its development in postmenopausal women. The polymorphism of estrogen receptor genes (ESR1, ESR2) seems essential among the genetic factors. The goal of this study was to analyze polymorphisms of selected genes in a population of postmenopausal women treated for osteoporosis and to evaluate the influence of genetic and nongenetic factors on the estimated 10-year risk of fracture. The study group consisted of 214 women hospitalized for treatment of postmenopausal osteoporosis. We investigated the presence of ESR1, ESR2, LRP5, and WNT16 genetic polymorphisms and the risk of fracture in each woman. The main finding was that of significant differences in the polymorphisms of the WNT16 rs2908004 genetic variant, notably, the less frequent presence of TC allele in women with a greater risk of osteoporotic fractures. We conclude that the polymorphism of the WNT16 gene seems highly relevant in the pathogenesis of osteoporosis, which makes it a promising object for further research on the genetic background of fracture risk.

Does Patient-Specific Instrumentation Improve Femoral and Tibial Component Alignment in Total Knee Arthroplasty? A Prospective Randomized Study.

Alignment of the prosthesis is one of the most significant factors that affect the long-term clinical outcome following total knee arthroplasty (TKA). There is conflicting evidence whether patient-specific instrumentation (PSI) for TKA improves the component position compared to standard instrumentation. This study aimed to compare the rotational alignment of the femoral and tibial components in TKA patients when performed with either conventional or PSI. Sixty patients with primary knee osteoarthritis were randomly divided into two groups treated surgically with TKA: one with conventional instrumentation and the other with the Visionaire PSI system (Smith and Nephew, Memphis, TN). Computerized tomography (CT) and X-ray imaging were performed preoperatively and 12 weeks after surgery. The rotational alignment of the femoral and tibial component in all patients was assessed postsurgically using CT imaging according to the Berger protocol. Both groups were clinically assessed in a blinded fashion using the Knee Society Score (KSS) and a visual analog scale (VAS). Fifty-eight patients were prospectively assessed. The mean postsurgical follow-up was 3.0 ± 0.4 months. CT images did not reveal any significant improvement in the rotational alignment of the implant components between the groups. X-rays revealed a significant improvement in the deviation from the optimal alignment range of the femoral component in the coronal plane in both groups. Patients operated with Visionaire PSI assistance had poorer functional outcomes. We conclude that there were no improvements in clinical outcomes or knee component alignment in patients treated with PSI compared with those treated with standard instruments. In addition, clinical and functional assessment showed inferior results in terms of KSS and VAS scores at the midterm follow-up in patients treated with PSI.