Aims

The processes linking long-term bisphosphonate treatment to atypical fracture remain elusive. To establish a means of exploring this link, we have examined how long-term bisphosphonate treatment with prior ovariectomy modifies femur fracture behaviour and tibia mass and shape in murine bones.

Aims

Carpal malalignment after a distal radial fracture occurs due to loss of volar tilt. Several studies have shown that this has an adverse influence on function. We aimed to investigate the magnitude of dorsal tilt that leads to carpal malalignment, whether reduction of dorsal tilt will correct carpal malalignment, and which measure of carpal malalignment is the most useful.

Aims

The use of frozen tumour-bearing autograft combined with a vascularized fibular graft (VFG) represents a new technique for biological reconstruction of massive bone defect. We have compared the clinical outcomes between this technique and Capanna reconstruction.

The histology and mechanics of leg lengthening by callus distraction were studied in 27 growing rabbits. Tibial diaphyses were subjected to subperiosteal osteotomy, held in a neutral position for 10 days and then slowly distracted at 0.25 mm/12 hours, using a dynamic external fixator. Radiographs showed that the gap became filled with callus having three distinct zones. Elongation appeared to occur in a central radiolucent zone; this was bounded by two sclerotic zones. Histologically, the radiolucent zone consisted of longitudinally arranged cartilage and fibrous tissue while the sclerotic zones were formed by fine cancellous bone. New bone occasionally contained islands of cartilage, suggesting it had been formed by endochondral ossification. After completion of distraction, the two sclerotic zones fused, shrank and were eventually absorbed, leaving tubular bone with a new cortex. When the periosteum had been removed at the operation, callus formation was markedly disturbed and there was failure of bone lengthening. Scraping of endosteum, in contrast, did not have a pronounced effect. These results suggest that the preservation of periosteum is essential if bone lengthening by callus distraction is to succeed, and that preservation of the periosteum is more important than careful corticotomy

Stereoradiography with a base shift of the source of illumination was used to produce pairs of radiographs to be measured by stereophotogrammetric techniques. The direction of shift was parallel with the longitudinal axis of the body, so that each radiograph in the stereopair could be used for other clinical purposes. A base shift of 10 centimetres with a distance of 100 centimetres between the focus and the film gave acceptable value of stereoscopic parallax. The radiographs were measured using a Hilger and Watts medical stereometer. This method was checked with test specimens, namely an osteotomised pelvis in which one acetabulum could be rotated and an osteotomised femur in which the whole upper portion could be rotated against the shaft. Measurements made on the acetabulum and its radiographs showed a correlation coefficient of 0.9838 over the range 0 to 30 degrees of anteversion, with a mean error +2.54 degrees and a standard deviation of +/- 1.52 degrees (n = 21). For the femoral neck, over the range from 10 degrees of retroversion to 80 degrees of anteversion, the correlation coefficient was 0.9979, the mean error +2.46 and the standard deviation +/- 1.48 degrees (n = 30)

1. Radiography of the spines of thirty-three West African patients recently recovered or dead from tetanus revealed vertebral fractures in nineteen. These fractures occurred most frequently in the fourth to eighth thoracic vertebrae. 2. The spines of 111 Nigerians from the same area of West Africa were examined, measurement of the areas and shape of the vertebral bodies carried out, and the proportional incidence of articular shelves and laminar spicules was calculated. 3. The upper mid-thoracic vertebral bodies are relatively long and narrow and have but little greater cross-sectional area than those immediately above them; possessing no neural arch supports to sustain longitudinal compressive forces in flexion, they are at greatest hazard during tetanic spasms. 4. Analyses of these factors and of the clinical features, together with experimental observations drawn from the literature, are used to explain the prevalence of upper mid-thoracic vertebral fractures as a complication of tetanus in West Africans, and in particular the greater degree of compression and higher incidence found in children. 5. Vertebral fracture is not usually an important complication of tetanus; it causes little pain, does not prolong the illness, gives rise to no permanent disability and has no effect on the mortality

Puppies in the second half of their growing period have been observed for one and a half to four and a half months after creation of a superficial femoral arteriovenous fistula on the right side. From measurements of the whole bone and from microradiographic and tetracycline-fluorophore studies of the diaphysial bone, it is believed that the following statistically significant phenomena may be attributed to the influence of the arteriovenous fistula. 1. All bones distal to the fistula are influenced in their growth. The tibia and metatarsals become heavier and larger, but retain normal shape. Although stimulation of longitudinal growth is small, it is significant for the tibiae and nearly significant for the femora in these short-term experiments. 2. The histological structure of the bones remains normal but quantitative changes are induced. The compact bone is more porous because of an increased number of osteones. Haversian turnover itself is affected in that the individual formation time of osteones tends to become longer, especially in the metatarsals. 3. Periosteal new bone formation is immediately stimulated, producing a flare of new bone. This accounts for the increase in diaphysial weight in the tibia but not in the metatarsals, where the same effect results from decreased resorption of old bone. 4. Endosteal new bone formation is depressed, especially in the metatarsals, resulting in an enlarged medullary cavity

1. One hundred and seventy-three hips in 138 patients have been examined and studied in reference to the type of treatment received. 2. Shepherd's method of assessing the results of arthroplasty operations has been adapted to this series. 3. Satisfactory results were found in 77·9 per cent of all patients. 4. The value of straight longitudinal traction is questioned. Medial rotation appears to be an essential step in the reduction of the deformity. 5. Manipulation was found to be a relatively safe and effective method of reducing the deformity in patients seen soon after an acute episode, and should be reserved for them. 6. Complications were common after nailing operations, and included subtrochanteric fracture in three cases. 7. Avascular necrosis was the commonest cause of a poor result. The two types of avascular necrosis are discussed. 8. Avascular necrosis was found in 37 per cent of cases in which a manipulation was followed by a nailing operation. 9. Avascular necrosis was not found in any case in which a manipulation was combined with the use of Moore's pins, but such cases were kept under observation for a shorter time. 10. Avascular necrosis was found in 38·1 per cent of cases of cervical osteotomy

We undertook a comparative study of magnetic resonance imaging (MRI) vertebral morphometry of thoracic vertebrae of girls with adolescent idiopathic thoracic scoliosis (AIS) and age and gender-matched normal subjects, in order to investigate abnormal differential growth of the anterior and posterior elements of the thoracic vertebrae in patients with scoliosis. Previous studies have suggested that disproportionate growth of the anterior and posterior columns may contribute to the development of AIS. Whole spine MRI was undertaken on 83 girls with AIS between the age of 12 and 14 years, and Cobb’s angles of between 20° and 90°, and 22 age-matched controls. Multiple measurements of each thoracic vertebra were obtained from the best sagittal and axial MRI cuts. Compared with the controls, the scoliotic spines had longer vertebral bodies between T1 and T12 in the anterior column and shorter pedicles with a larger interpedicular distance in the posterior column. The differential growth between the anterior and the posterior elements of each thoracic vertebra in the patients with AIS was significantly different from that in the controls (p < 0.01). There was also a significant positive correlation between the scoliosis severity score and the ratio of differential growth between the anterior and posterior columns for each thoracic vertebra (p < 0.01). Compared with age-matched controls, the longitudinal growth of the vertebral bodies in patients with AIS is disproportionate and faster and mainly occurs by endochondral ossification. In contrast, the circumferential growth by membranous ossification is slower in both the vertebral bodies and pedicles

Chondrocytes at the lower zone of the growth plate must be eliminated to facilitate longitudinal growth; this is generally assumed to involve apoptosis. We attempted to provide definitive electron-microscopic evidence of apoptosis in chondrocytes of physes and chondroepiphyses in the rabbit. We were, however, unable to find a single chondrocyte with the ultrastructure of ‘classical’ apoptosis in vivo, although such a cell was found in vitro. Instead, condensed chondrocytes had a convoluted nucleus with patchy chromatin condensations while the cytoplasm was dark with excessive amounts of endoplasmic reticulum. These cells were termed ‘dark chondrocytes’. A detailed study of their ultrastructure combined with localisation methods in situ suggested a different mechanism of programmed cell death. In addition, another type of death was identified among the immature chondrocytes of the chondroepiphysis. These cells had the same nucleus as dark chondrocytes, but the lumen of the endoplasmic reticulum had expanded to fill the entire non-nuclear space, and all cytoplasm and organelles had been reduced to dark, worm-like inclusions. Since these cells appeared to be ‘in limbo’, they were termed ‘paralysed’ cells. It is proposed that ‘dark chondrocytes’ and ‘paralysed cells’ are examples of physiological cell death which does not involve apoptosis. It is possible that the confinement of chondrocytes within their lacunae, which would prevent phagocytosis of apoptotic bodies, necessitates different mechanisms of elimination

1. The healing of the radius and tibia in dogs after compression plating of osteotomies made by a Gigli saw was studied. 2. The methods used were indian ink microangiography and terramycin labelling. The Spalteholz technique and azane colouring were used. 3. Revascularisaton of the fracture region took place both from newly formed vessels in the Haversian systems and from periosteal and endosteal vessels. 4. The fracture gap was filled at an early stage by a vascular network. Under stable conditions direct angiogenic bone formation took place around this network. 5. Rebuilding of the cortical bone in the fracture region occurred by osteoclastic activity. Groups of osteoclasts made cavities in the necrotic bone and were immediately followed by loops of vessels; behind and around the loop new bone was formed. Another form of bone absorption consisted of bundles of vessels which eroded necrotic cortical bone without new bone formation. 6. The new bone was initially oriented along the fracture gap but, by conversion into secondary osteones, it became progressively oriented longitudinally in the direction of the original bone. 7. Under stable conditions some periosteal and endosteal callus formation occurred though it was of slight importance. It regressed very soon and was seldom seen in the radiographs

Aims

To devise a method to quantify and optimize tightness when inserting cortical screws, based on bone characterization and screw geometry.

We aimed to evaluate the precision and longitudinal sensitivity of measurement of bone mineral density (BMD) in the pelvis and to determine the effect of bone cement on the measurement of BMD in femoral regions of interest (ROI) after total hip arthroplasty (THA). A series of 29 patients had duplicate dual-energy x-ray absorptiometry (DXA) scans of the hip within 13 months of THA. Pelvic analyses using 3- and 4-ROI models gave a coefficient of variation (CV) of 2.5% to 3.6% and of 2.5% to 4.8%, respectively. Repeat scans in 17 subjects one year later showed a significant change in BMD in three regions using the 4-ROI model, compared with change in only one region with the 3-ROI model (p < 0.05). Manual exclusion of cement from femoral ROIs increased the net CV from 1.6% to 3.6% (p = 0.001), and decreased the measured BMD by 20% (t = 12.1, p < 0.001). Studies of two cement phantoms in vitro showed a small downward drift in bone cement BMD giving a measurement error of less than 0.03 g/cm. 2. /year associated with inclusion of cement in femoral ROIs. Changes in pelvic periprosthetic BMD are best detected using a 4-ROI model. Analysis of femoral ROI is more precise without exclusion of cement although an awareness of its effect on the measurement of the BMD is needed

Aims

The consensus is that bipolar hemiarthroplasty (BHA) in allograft-prosthesis composite (APC) reconstruction of the proximal femur following primary tumour resection provides more stability than total hip arthroplasty (THA). However, no comparative study has been performed. In this study, we have compared the outcome and complication rates of these two methods.

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To evaluate the donor site morbidity and tendon morphology after harvesting whole length, full-thickness peroneus longus tendon (PLT) proximal to the lateral malleolus for ligament reconstructions or tendon transfer.

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The aim of this study is to report the results of a case series of olecranon fractures and olecranon osteotomies treated with two bicortical screws.

We studied the vascular pattern of human posterior tibial tendons by injection techniques and immunohistochemically using antibodies against laminin. The intravascular volume of the posterior tibial tendon was determined using a new method of injection of a solution of . 99m. Tc and gelatin ink into the lower legs of cadavers. Three segments of 1 cm length from different regions of the human posterior tibial tendon were measured using a gamma well counter. The main blood supply arises from the posterior tibial artery. Blood vessels enter the paratenon of the posterior tibial tendon via a mesotenon from the posterior aspect. From the paratenon, the blood vessels penetrate the posterior tibial tendon and anastomose with a longitudinally orientated intratendinous network. The number of vessels in the substance of the tendon is consistently less than that in the surrounding paratenon. The distribution of blood vessels within the posterior tibial tendon is not homogeneous. In the retromalleolar region the intravascular volume was significantly reduced with a mean value of 15 μl/g of tendon tissue. There was no significant difference between the mean intravascular volumes of the proximal and distal areas (distal, 27.7 μl/g tendon tissue; proximal, 30 μl/g tendon tissue). The immunohistochemical investigation showed that there was no immunostaining for laminin in the anterior part of the tendon in the region where it passes behind the medial malleolus. This region is avascular. The most frequent site of rupture of the posterior tibial tendon is in the region behind the medial malleolus. A potential endogenous risk factor may be the limited healing potential of avascular tissue

In this review, we discuss the evidence for patients returning to sport after hip arthroplasty. This includes the choices regarding level of sporting activity and revision or complications, the type of implant, fixation and techniques of implantation, and how these choices relate to health economics. It is apparent that despite its success over six decades, hip arthroplasty has now evolved to accommodate and support ever-increasing patient demands and may therefore face new challenges.

Cite this article: Bone Joint J 2020;102-B(6):661–663.