Purpose of the study: Hip resurfacing (HR) is becoming popular again with the advent the the metal-on-metal bearing. This type of surgery is proposed for young, often very active, patients for whom restoration of optimal hip joint range of motion constitutes and important objective. The purpose of this work was to analyse anterior translation of the femoral component to optimise joint range of motion (particularly flexion).

Material and method: From September 2007 to May 2008, 68 hip resurfacing prostheses were implanted in 66 patients aged on average 45 years (range 19–61). All procedures were performed by the same operator using a posterorlateral approach and the same surgical technique. Anterior head-neck offset was a constant objective. The Postel-Merle-d’Aubigné and Harris scores as well as the Devane classification and the WOMAC and the SF-12 were noted. Joint range of motion was noted preoperatively and at last follow-up by and independent operator. Anterior head-neck offset was measured radiographically on the Dunn view using an original technique and calibrated by the Imagika software according to the known diameter of the implants.

Results: All clinical scores as well as the activity level and the subjective scores improved significantly. There were no revisions. The mean anterior head-neck offset was 4.5 mm (range 2–9). Significant correction was observed for gain in postoperative flexion and increased offset (p< 0.005). The group of patients who had an anterior offset considered to be significant (> 4 mm) exhibited significantly better flexion than the group of patients with a small anterior offset.

Discussion: Hip resurfacing has a poor head-neck ratio, depending on the patient’s anatomy, which compares unfavourable with conventional hip prostheses (THA). Nevertheless, the joint range of motion after resurfacing, as observed in our study and in the literature, does not show any decline compared with THA. The greater gain in flexion is an important factor to take into consideration, especially in a young active athletic subject. Each millimetre of gain in anterior offset produces a significant increase in flexion. This offset can be improved by the surgical technique (implanting the femoral component tangentially to the posterior cortical), but also by the design of the resurfacing prosthesis (thick femoral component, increased cement sheath). After hip resurfacing, anterior offset appears to be an essential biomechanical factor for restoration of joint motion.

Advisors. PhD J Hartvigsen, PhD P Aagaard, University of Southern Denmark. PhD G Br⊘nfort, Northwestern Health Sciences University, Minneapolis, MN, USA and NIKKB. PhD G Kawchuk, Canada Research Chair in Spinal Function, University of Edmonton, Alberta, Canada. PhD A Breen, Institute for muscoloskeletal research & clinical implementation, Bournemouth, England. PhD J Rasmussen, Institut for Maskinteknik og Anybody Group, Aalborg Universitet. Introduction. The overall issue of this project is to investigate the relationship between the lumbar spinal biomechanics, patient's pain and physiological effects of traditional conservative treatments. Background. Biomechanical factors such as ranges, patterns and quality of motion in the lumbar spine are thought to be important contributors to many varieties of LBP. Furthermore, commonly used treatments for spine pain such as exercises, training, and various manual treatments such as manipulation are thought to alter biomechanical factors and thereby facilitating return to “normal” function and thus a pain free state. Method. A systematic critical literature review in order to determine the current reproducibility level for measuring 3D regional lumbar spinal motion with various methods and based on the review propose an agenda for future research. Develop of a model to analyze the dynamic non-invasive computerized regional motion data. In this model the complex motion data will be reduced to a manageable size with each movement parameter consisting of individual figures. The data reduction will be done in a developed MATLAB program and the analysis of the reduced data will be handled in STATA. Use collected data from randomized clinical trials (research center at Northwestern Health Sciences University in Minnesota, USA) on the developed model in a reproducibility study and an intervention study

Anterior cruciate ligament (ACL) injuries are among the most common and debilitating knee injuries in professional athletes with an incidence in females up to eight-times higher than their male counterparts. ACL injuries can be career-threatening and are associated with increased risk of developing knee osteoarthritis in future life. The increased risk of ACL injury in females has been attributed to various anatomical, developmental, neuromuscular, and hormonal factors. Anatomical and hormonal factors have been identified and investigated as significant contributors including osseous anatomy, ligament laxity, and hamstring muscular recruitment. Postural stability and impact absorption are associated with the stabilizing effort and stress on the ACL during sport activity, increasing the risk of noncontact pivot injury. Female patients have smaller diameter hamstring autografts than males, which may predispose to increased risk of re-rupture following ACL reconstruction and to an increased risk of chondral and meniscal injuries. The addition of an extra-articular tenodesis can reduce the risk of failure; therefore, it should routinely be considered in young elite athletes. Prevention programs target key aspects of training including plyometrics, strengthening, balance, endurance and stability, and neuromuscular training, reducing the risk of ACL injuries in female athletes by up to 90%. Sex disparities in access to training facilities may also play an important role in the risk of ACL injuries between males and females. Similarly, football boots, pitches quality, and football size and weight should be considered and tailored around females’ characteristics. Finally, high levels of personal and sport-related stress have been shown to increase the risk of ACL injury which may be related to alterations in attention and coordination, together with increased muscular tension, and compromise the return to sport after ACL injury. Further investigations are still necessary to better understand and address the risk factors involved in ACL injuries in female athletes.

Cite this article: Bone Jt Open 2024;5(2):94–100.

Introduction: Degenerative osteoarticular conditions of the lower limb comprise of the most common orthopedic diseases requiring implants surgery. Biomechanical factors have an important role in the development of the degenerative process. Radiological diagnostics prominently rely on bidirectional 2D X-ray images, CT and MRI also being employed in the assessment process. However, these diagnostic tools usually cover a single joint, mostly unilaterally, rarely if ever providing a chance to simultaneously examine each members of the closed kinetic chain of both limbs under normal postural loads in a standing position. Classification and measurements of anatomical conditions are carried out in a 2D environment only and measured values are projected to real-life circumstances. EOS, a new 2D/3D digital imaging system based on Nobel-prize winning ultra low-dose X-ray radiation detection and a unique 3D toolbox with 3D reconstruction module offers a truly groundbreaking option in this field. We present results obtained during the first year of clinical use of our EOS 2D/3D system. Methods: 20 patients with coxarthrosis and 20 patients with gonarthrosis have been examined with traditional 2D X-ray and EOS 2D/3D system. Clinical parameters (femoral and tibial length, mechanical angle of the femur and tibia, anatomical and mechanical femorotibial angle, etc.) have been determined for both diagnostic methods and results were compared. 3D measurements available within EOS 3D toolbox were determined including femoral and tibial torsion and femorotibial rotation. For visualization of the lower limbs EOS 3D reconstructions were made. Results: Using EOS built-in 3D toolbox, comparison of numerical data for 2D and 3D measurements of clinical parameters showed a significant difference whereby 3D measurements always represented more valid, more accurate values. Differences between 2D and 3D measurement values were as much as 5–10 mm in length or 5–8 degrees in angles. This was particularly true for conditions where torsion and rotation of the bones were present. EOS 3D reconstruction module provided a surface reconstructed 3D model of the examined limbs and automatically displayed every clinically relevant parameters measured in the 3D toolbox. This proved to be an important feature for pre-operative planning and postoperative evaluations. Conclusion: EOS 2D/3D system provides a ground-breaking new tool for length and angle measurements of the lower limb in 3D, providing distortion-free clinical parameters that are accurate and true-to-life values, avoiding artefactual effects from projection, torsion and rotation and positioning of the patient, which usually concomitantly affect the accuracy and reproducibility of conventional 2D measurements