Aims

Abnormal femoral torsion (FT) is increasingly recognized as an additional cause for femoroacetabular impingement (FAI). It is unknown if in-toeing of the foot is a specific diagnostic sign for increased FT in patients with symptomatic FAI. The aims of this study were to determine: 1) the prevalence and diagnostic accuracy of in-toeing to detect increased FT; 2) if foot progression angle (FPA) and tibial torsion (TT) are different among patients with abnormal FT; and 3) if FPA correlates with FT.

CT scans of 18 hips with typical congenital dislocation have been studied in 16 children. These show that the common position of dislocation is lateral, superior and slightly anterior, and that a "false acetabulum" can be distinguished even in young children. A defect in the posterior ischium causing distortion of the acetabulum was also present in most cases. The cartilage and the acetabular contents were well shown. Positions of reduction and the anteversion of the acetabulum and the femoral neck were studied. Hypotheses are presented on the mode of dislocation and on the cause of the pathological changes

Specimens of tissue from haemophilic synovium and articular cartilage were collected from 39 patients during reconstructive surgery. They were studied by histochemistry, electron microscopy and microprobe analysis. The detailed findings are presented and discussed. It is suggested that haemophilic arthropathy is the result of a number of mechanisms affecting the synovial lining which becomes progressively fibrotic and the hyaline cartilage which disintegrates and is eventually lost. Mechanical and chemical processes cause degeneration of cells but enzymatic processes appear to be primarily responsible for the degradation of the matrix of the articular cartilage

We applied joint distraction using an Ilizarov apparatus in 11 patients with post-traumatic osteoarthritis of the ankle to try to delay the need for an arthrodesis. Distraction for three months resulted in clinical improvement in pain and mobility for a mean of two years, with an increase in the joint space. We considered that these effects may be produced by the absence of mechanical stress on the cartilage combined with the intra-articular hydrostatic pressures during distraction. We measured these pressures during walking with distraction, and found levels very similar to those reported to improve osteoarthritic cartilage when applied in vitro

1. The importance of recognising osteochondral fractures of the femoral condyle in the adolescent knee joint is emphasised. 2. The mechanism of the formation of the fractures is discussed. Essentially, a powerful rotary and compressive force shears off cartilage and subchondral bone. The absence of lateral condylar lesions in the experimental group lends support to the theory that the patella may cause the fracture by impingement. 3. On the basis of the mechanism a clinical classification of osteochondral fractures of the femoral condyles is presented. 4. Early surgery is recommended. The arguments for removal or replacement of the fragment are discussed

1. All articulating cartilages are fibrocartilages. 2. The articular cartilages of the synovial joints are largely composed of collagen fibres. 3. These fibres form a dense network, the fibres of which run obliquely between the articular surface and the bone. 4. This network is operative when the parts are at rest and in contact under pressure. It takes the tensile component of the resultant shear stress, and is a postural mechanism of the joint. 5. The articular cartilage is most heavily chondrified at its centre, between the juxta-synovial and juxta-osseous parts. 6. The technique for demonstrating the fibrous structure is described

We studied the most superficial layer of macroscopically normal articular cartilage obtained from human femoral heads, using polarising microscopy and SEM. The most superficial layer, 4 to 8 microns thick, was acellular consisting of collagen fibrils. This layer could be peeled away as a thin film, with no broken collagen fibrils on its inferior surface or on the surface of subjacent cartilage layers. The orientation and diameter of collagen fibrils were different on these two surfaces. Our findings suggest that the most superficial layer is an independent one which is only loosely connected to the fibrous structure in the layer deep to it

Objectives

X-linked hypophosphataemic rickets (XLHR) is a disease of impaired bone mineralization characterized by hypophosphataemia caused by renal phosphate wasting. The main clinical manifestations of the disorder are O-shaped legs, X-shaped legs, delayed growth, and bone pain. XLHR is the most common inheritable form of rickets, with an incidence of 1/20 000 in humans. It accounts for approximately 80% of familial cases of hypophosphataemia and serves as the prototype of defective tubular phosphate (PO4³⁺) transport, due to extra renal defects resulting in unregulated FGF23 activity. XLHR is caused by loss-of-function mutations in the PHEX gene. The aim of this research was to identify the genetic defect responsible for familial hypophosphataemic rickets in a four-generation Chinese Han pedigree and to analyze the function of this mutation.

Aims

There has been a recent resurgence in interest in combined partial knee arthroplasty (PKA) as an alternative to total knee arthroplasty (TKA). The varied terminology used to describe these procedures leads to confusion and ambiguity in communication between surgeons, allied health professionals, and patients. A standardized classification system is required for patient safety, accurate clinical record-keeping, clear communication, correct coding for appropriate remuneration, and joint registry data collection.

1. Clinical studies in humans have indicated that a delay of one to three weeks in the open reduction of a fracture decreases the incidence of delayed union and non-union. 2. Studies in cats indicate that a delay of two weeks before open reduction causes a different repair mechanism from that following immediate operation. 3. Repair after delayed operation is characterised by increased periosteal new bone formation and more rapid endochondral bone formation. After immediate operation periosteal new bone is slow to develop; much more fibrous tissue and cartilage develop, followed by slow endochondral bone formation

1. Periosteal bone is supplied by periosteal vessels and endochondral bone by the nutrient artery. 2. In the earliest stages of development the metaphysis is supplied by vessels derived only from the nutrient artery. Later, metaphysial arteries derived from the periosteum take over the supply of its peripheral part, the extent of their area of supply progressively increasing. 3. In injected specimens the blood vessels approaching the epiphysial cartilaginous plate end in saccular dilations. Histological sections show these dilations to be blood-filled cartilage lacunae, with no endothelial lining and into which open the blood vessels approaching the epiphysial plate

1. The bone changes in four autopsied cases of Cushing's syndrome are described. The changes take the form of osteoporosis, which is most marked in the spine and the ribs. 2. The osteoporosis results from impaired osteoblastic bone formation in the presence of a normal degree of osteoclastic bone resorption. 3. Histological abnormalities of fracture callus in Cushing's syndrome indicate interference with the proliferation of osteoblasts and cartilage cells and with the formation of new tissue by these cells. 4. The bone changes in Cushing's syndrome are comparable with those produced in experimental animals by the administration of A.C.T.H. or cortisone

1. Because of the importance of nutrition of the intervertebral disc in relation to its disorders, a detailed study has been made of the neighbouring vasculature of the vertebral body. 2. This has been made possible by an injection technique involving prevention of leakage by freezing with liquid nitrogen. 3. By this method capillary beds are found in the vertebral end-plate cartilage in the adult. A very fine subchondral post-capillary venous network has been demonstrated draining by short vertical tributaries to a much coarser horizontal collecting vein system connecting with the familiar basivertebral system. 4. This arrangement may be of special importance in the nutrition of the intervertebral disc

An experimental method is described which permits observations on the early stages of repair after acute displacement of the upper femoral epiphysis. Because the epiphysis is intra-articular, displacement brings about avascular necrosis which is slowly repaired by ingrowth of callus and blood vessels from the stump of the neck. As the bulk of the epiphysial plate remainsattached to the epiphysis, it acts as a barrier to successful revascularisation. Deliberate removal of the epiphysial cartilage allows earlier revascularisation. It is suggested that in clinical cases reduction be done through the epiphysial plate rather than through the neck, and that it be accompanied by curettage of the remaining part of the epiphysial plate from the under surface of the head

We report the cases of three children with chronic injuries of the medial tibial malleolus caused by traction injuries during sport. All three had the triad of swelling of the medial malleolus, tenderness over its anterior part, and pain on forced valgus movement of the foot. Radiographs showed bilateral accessory ossification centres and MRI demonstrated partial avulsion or avulsion fracture of the apophyseal cartilage and fragmentation of the accessory centres. A review of 134 young basketball players showed that 25% had tenderness of the anterior medial malleolus. This high rate indicates that traction apophysitis of the medial malleolus is not uncommon in children as a sports-related disorder

We have performed a prospective, single-surgeon study analysing the histological results of autologous chondrocyte implantation. Fourteen patients underwent autologous chondrocyte implantation of the knee and were evaluated at one year by clinical assessment and arthroscopy. Standard staining was used to examine the sections. In addition, in situ hybridisation was used to establish type-IIa and type-IIb collagen mRNA expression and immunolocalisation techniques demonstrated the positions of type-II and type-X collagen. Eight patients regenerated hyaline cartilage and also contained type-X collagen in the deepest layers and type-II collagen in the deep layers. Three demonstrated fibrocartilage and had type-II collagen in the deep layers. In situ hybridisation revealed that all 14 samples had the potential to express both type-IIa and type-IIb collagen. We have shown that one year after the initial implantation chondrocytes are capable of producing type-II collagen and that they continue to proliferate and mature

Throughout this work data have been gathered favouring the concept that the metaphysial vascular arrangement is primarily related to the process of enchondral ossification, and has very limited, if any, responsibility for the nourishment of the growth cartilage. The present evidence favours the suggestion that when the chondrocytes of the column have become too far separated from their source of nourishment (the epiphysial vessels) they and their surrounding matrix suffer changes which prepare them for the process of calcification. At least calcium and phosphate ions will be required for this to take place. The proximity of the vessel and also the fact that it is not isolated by a membrane at its very end suggests a profuse interchange of fluids with the surrounding area

We have compared the findings of MRI with those of hip arthroscopy in 23 hips in young adults with hip pain. Large deep cartilage deficiencies on the acetabulum or femoral head, the percentage of femoral head cover, and the presence of marginal osteophytes seen on MRI correlated well with those seen at arthroscopy, but chondral softening, fibrillation, or partial-thickness defects less than 1 cm in diameter were less consistently detected by MRI. Osteochondral loose bodies and labral tears were not well demonstrated by MRI, but were readily identified and treated at arthroscopy. Arthroscopy of the hip is a useful investigation for hip pain in young adults especially when standard non-invasive MRI fails to provide a clear diagnosis

Nuclear magnetic resonance imaging (MRI) was used to study the normal knee. As well as revealing bone quality, MRI provided useful information on intra-articular and extra-articular soft tissues. Midsagittal views gave clear images of the cruciate ligaments, and of the patellar and quadriceps tendons. Parasagittal views were the best for delineating the menisci which, like ligaments and tendons, are of low intensity; the semimembranosus tendon and its insertion to the proximal tibia were also seen clearly in these views. The cruciate ligaments and menisci, though visible in the coronal view also, were better seen in the sagittal view. Axial views provided information on the structure of the patella, its cartilage, the patellofemoral joint and posterior soft-tissue structures