Introduction. Osteoarthritis continues to be a major cause of pain and disability. The pathological processes leading to the end-stage of joint degeneration remain poorly understood. Advances in radiological imaging have the potential to improve understanding of the structural and functional changes observed in OA. The aim of this study was to describe the microarchitecture of the femoral head in osteoarthritis. Methods. Twenty osteoarthritic femoral heads underwent micro-computed tomography scanning at 30µm. Four parameters of micro-architecture and structure were determined: bone volume ratio (BV:TV), trabecular thickness, structural model index and degree of anisotropy. The femoral head was divided into 27 cubic volumes of interest. Analysis of variance (ANOVA) was used to assess differences between regions. Cystic and sclerotic changes were assessed qualitatively. Results. There was marked heterogeneity in the density and architecture throughout the head. The greatest density and trabecular thickness was found in a central core that extended from the medial calcar to the physeal scar (ANOVA p< 0.001). This region also correlated with the greatest degree of anisotropy (DA=2.4, p< 0.001), plate-like trabeculae (SMI=−0.22, p< 0.001). All osteophytes exhibited a radially orientated trabecular pattern, in close relation to the superior and inferior nutrient foramina in the region of the physeal scar. Cartilage eburnation was associated with loss of the normal subchondral structure of radially-orientated trabeculae and replacement by thickened lamellar bone. Discussion. This study demonstrated marked structural heterogeneity at the 30 µm resultion and the micro-architectural changes associated osteophytes, cysts and sclerosis. The elucidation of the osseous microstructure can clarify the interaction between geometry and function in OA. Further work is necessary to relate this to underlying pathogenic process to determine the temporal sequence of microarchitectural changes

Conventionally, medial malleolus fractures are treated surgically with anatomical reduction and internal fixation using screws. There seems to be no consensus, backed by scientific study on the optimal screw characteristics in the literature. We retrospectively examined case notes and radiographs of 48 consecutive patients taken from our trauma database (21 male, 27 female) with an average age of 50 years (range 16-85) who had undergone medial malleolus fracture fixation with screws at the Royal Free Hospital, London between January 2009 and June 2010. The most commonly used screw was the AO 4.0 mm diameter cancellous partially-threaded screw in 40, 45 and 50 mm lengths (40 mm n = 28, 45 mm n = 26, 50 mm n = 23) with the threads passing beyond the physeal scar in all cases. Incomplete reduction defined as > 1mm fracture displacement was observed on post-operative x-rays in 12 out of 48 cases (25%), all of which relied on partially-threaded screw fixation. In 5 cases where AO 4.0 mm diameter fully-threaded screws engaging the physeal scar had been used, no loss of reduction was observed. This unusual, occasional use of fully-threaded screws prompted us to investigate further using a porcine model and adapted pedo-barographic transducer. We compared pressures generated within the fracture site using AO 4.0 mm partially-threaded cannulated screws, 4.0 mm partially-threaded cancellous screws and 4.0 mm fully-threaded cancellous screws. Fully-threaded cancellous 4.0 mm diameter screws generated almost 3 times the compression of a partially-threaded cancellous screw with superior stability at the fracture. Partially-threaded screws quickly lost purchase, compression and stability particularly when they were cannulated. We also observed that screw thread purchase seemed enhanced in the physeal region. We conclude that fully-threaded cancellous 4.0 mm AO screws are superior to longer partially-threaded screws and that use of cannulated 4.0 mm partially-threaded screws should be avoided in fixation of medial malleolus fractures

Introduction:. Recent published studies have examined the normal dimensions of the syndesmosis on CT. However, previous anatomical studies have shown variations of the articulating facets within the tibialae fibularis and may contribute to the false appearance of increased spacing within the syndesmosis. In this study, we measured and compared anterior and posterior distances of the distal tibiofibular(DTF) syndesmosis on MRI and CT imaging. Methods:. We identified adult patients who had had both a CT scan and an MRI scan of their ipsilateral ankle to investigate symptoms unrelated to the DTF syndesmosis. The anterior and the posterior DTF dimensions were measured on CT and MRI axial images, at the level of the distal tibial physeal scar. This was taken from anterior tubercle of tibia and from the most anterior aspect of the posterior tibial tubercle to the nearest point of medial aspect of the fibula. The geometrical shapes of the syndesmosis and the anterior tibial tubercle were also recorded. Results:. 16 ankles in 15 patients were included. The mean age was 34.6+/−8.8 years. The mean (SD) for the anterior DTF distance was 2.0 mm (0.7 mm) on MRI and 2.9 mm (0.9 mm) on CT whilst the mean posterior DTF distance was 3.2 mm (1.1 mm) on MRI and 4.3 mm (1.0 mm) on CT. This difference reached statistical significance (p < 0.001, paired T-test). When examining the shape of the syndesmosis on MRI, 56% were crescent and 44% rectangular, this was compared to 69% and 31%, respectively, on CT. There was, however, no statistical difference in the shape of the syndesmosis between the two radiological modalities (p=0.625, McNemar test). Conclusion:. CT appears to over-estimate the distal tibiofibular separation and may lead to a false positive diagnosis. Further studies are needed to establish the reliability in the use of CT scans to investigate normal and abnormal syndesmosis

Introduction and Aims: Anterior cruciate ligament (ACL) injuries have historically been classified as non-contact or contact based on the mechanism of injury. The purpose of this study was to establish a detailed correlation between mechanism and the associated osteochondral, meniscal and other injuries to improve understanding of this common injury and its outcome. Method: A descriptive analysis of prospectively collected data on ACL injuries requiring reconstruction between 2000 and 2004 was completed. Mechanism of injury was clearly elicited and correlated with clinical, radiologic and operative findings. Magnetic resonance imaging (MRI) was performed on all patients to analyse patterns of ACL rupture and associated osteochondral, meniscal and ligament injuries. Osteochondral injuries were analysed by a musculoskeletal radiologist according to location, intensity and depth. Intra-operative documentation of intra-articular injury pattern was also performed and correlated with MRI findings. Classification into ‘active’ (non-contact) and ‘passive’ (contact) mechanisms was completed and correlated with injury pattern. Results: Seventy patients were identified with appropriate clinical, radiologic and operative data. A thorough review of the events surrounding the injury was documented. Forty-six patients described an active mechanism and 24 patients a passive mechanism of injury. Clinical examination demonstrated a similar proportion of medial collateral ligament injuries in each group. MRI within three months of injury demonstrated occult osteochondral lesions or ‘bone bruises’ in the majority of patients. Clear distinguishing patterns of femoral and tibial osteochondral injury were identified in the active and passive groups. Depth of osteochondral injury was most commonly classified as at least two-thirds the distance to the physeal scar in both groups. Intensity of the abnormal edema-like signal in the marrow of the distal femur and proximal tibia was most commonly classified as severe in both groups. Lateral meniscus injury was more common than medial, and was found in the majority of patients, more commonly in the passive group. Conclusion: Although surgical techniques continue to improve, the ACL injury mechanism and its relation to intra-articular pathology is less well defined. This study defines either ‘active’ or ‘passive’ mechanisms, with implications for likely associated osteochondral and meniscal injury. This gives valuable insight into the ACL injured knee, its management, and eventual prognosis

Femoroacetabular impingement (FAI) causes pain and chondrolabral damage via mechanical overload during movement of the hip. It is caused by many different types of pathoanatomy, including the cam ‘bump’, decreased head–neck offset, acetabular retroversion, global acetabular overcoverage, prominent anterior–inferior iliac spine, slipped capital femoral epiphysis, and the sequelae of childhood Perthes’ disease.

Both evolutionary and developmental factors may cause FAI. Prevalence studies show that anatomic variations that cause FAI are common in the asymptomatic population. Young athletes may be predisposed to FAI because of the stress on the physis during development. Other factors, including the soft tissues, may also influence symptoms and chondrolabral damage.

FAI and the resultant chondrolabral pathology are often treated arthroscopically. Although the results are favourable, morphologies can be complex, patient expectations are high and the surgery is challenging. The long-term outcomes of hip arthroscopy are still forthcoming and it is unknown if treatment of FAI will prevent arthrosis.

The February 2014 Foot & Ankle Roundup³⁶⁰ looks at: optimal medial malleolar fixation; resurfacing in the talus; predicting outcome in mobility ankles; whether mal-aligned ankles can be successfully replaced; cartilage colonisation in bipolar ankle grafts; CTs and proof of fusion; recalcitrant Achilles tendinopathy; and recurrent fifth metatarsal stress fractures.

Pathological fractures in children can occur as a result of a variety of conditions, ranging from metabolic diseases and infection to tumours. Fractures through benign and malignant bone tumours should be recognised and managed appropriately by the treating orthopaedic surgeon. The most common benign bone tumours that cause pathological fractures in children are unicameral bone cysts, aneurysmal bone cysts, non-ossifying fibromas and fibrous dysplasia. Although pathological fractures through a primary bone malignancy are rare, these should be recognised quickly in order to achieve better outcomes. A thorough history, physical examination and review of plain radiographs are crucial to determine the cause and guide treatment. In most benign cases the fracture will heal and the lesion can be addressed at the time of the fracture, or after the fracture is healed. A step-wise and multidisciplinary approach is necessary in caring for paediatric patients with malignancies. Pathological fractures do not have to be treated by amputation; these fractures can heal and limb salvage can be performed when indicated.