Blood flow in intact tendons in dogs was measured using 57Co-labelled microspheres and compared with the simultaneous clearance of a diffusible radionuclide, 85Sr, by the same tendons. Clearance was significantly greater than flow in all tendons, indicating that diffusion from surrounding tissues may be important in the nutrition of normal tendons

The use of an osteocutaneous free fibular graft as a single-stage reconstructive procedure for composite tissue loss is increasingly common. Detailed anatomical study in cadavers of the blood supply to the graft demonstrates cutaneous arteries arising from the peroneal artery and then passing along the posterior surface of the lateral intermuscular septum. These vessels pierce the crural fascia and then ramify to supply the skin. Knowledge of the vascular anatomy of the skin overlying the fibula is essential to the success of the graft

The systemic arterial pressure has been used as a guide for determining the susceptibility to surgical bleeding during controlled hypotensive anaesthesia. Arterial hypotension is not, however, necessarily accompanied by venous or intraosseous hypotension. The main source of bleeding during posterior spinal surgery is the bone and is venous rather than arterial. The intraoperative blood loss, the intraosseous pressure (IOP) within the first thoracic vertebral body, and the systemic arterial pressure were measured in 27 patients during cervical laminoplasty for spondylotic myelopathy. The intraoperative blood loss correlated significantly with the vertebral IOP (p = 0.0073, r = 0.499), but not with systemic arterial pressure, age, or body-weight. The systemic arterial pressure did not correlate with the vertebral IOP. The mean value of the mean arterial pressure throughout the operation varied between 74 and 110 mmHg. The findings suggest that the vertebral IOP parallels surgical bleeding during posterior spinal surgery under normotensive anaesthesia and that patients with a low arterial pressure do not necessarily have a low IOP

There has been a long-standing debate as to whether medullary or periosteal flow is the dominant vascular supply during the healing of diaphyseal fractures. We used radioactive microspheres to quantify blood flow to the canine tibia two weeks after an osteotomy. There was a significant contribution from the periosteum to the blood supply of healing cortical bone after nutrient artery ligation, with a reversal of flow from a centrifugal to a centripetal direction. Our study has confirmed the qualitative observations of Trueta (1974) regarding the significant recruitment of vessels from surrounding soft tissue during fracture healing. We have not studied the later stages of healing

The blood supply of the flexor and extensor tendons of the fingers is described. The blood-vascular system consists of main feeding channels which supply a longitudinal network of vessels. These lie in the interfascicular connective tissue. A variation of the typical intratendinous vascular pattern in relation to the proximal interphalangeal joint is described

We have reviewed prospective data on 1016 patients who underwent unilateral total hip replacement to establish the pre-operative risk factors associated with peri-operative blood transfusion. Most patients who required transfusion were older and were of lower weight, height, pre-operative haemoglobin level and body mass index than patients who were not transfused. Multivariate analysis revealed that only the pre-operative haemoglobin level and the patients weight were identified as significant independent factors increasing the need for transfusion (p < 0.001). A haemoglobin level below 12 g/dl was associated with a threefold increase in transfusion requirement

1. The behaviour of various types of cortical bone graft has been studied in rabbits by histological and injection techniques. 2. The results suggest that penetration of the graft by blood vessels plays an important part in the incorporation of autogenous and homogenous grafts. 3. Autogenous and homogenous grafts are both incorporated–the latter more slowly than the former–but heterogenous grafts are rejected. The reasons for this rejection are discussed

1. By the surgical division of the main capsular artery supplying the upper femoral epiphysis of the rabbit it is possible to cause changes which resemble those occurring in human osteochondritis. 2. The phase of anaemia (ischaemia and hypovascularisation) lasts in the rabbit less than fifteen days. The whole process lasts approximately ninety days, and only for one-sixth of this period does the femoral head suffer from a reduction in its blood supply. 3. After the fifteenth day until the end of the process the condition changes to one of hypervascularisation, which lasts six times longer than that of ischaemia or relative anaemia. 4. By the ninetieth day the whole process has lost its activity and only some permanent deformities remain. The vascular pattern is from then on the normal in the rabbit. 5. The "osteochondritic" changes cannot be elicited in the distal femoral epiphysis. The apparent reason is the presence of anastomoses between the main artery and other epiphysial vessels. 6. There seems to be reasonable experimental evidence, by implication, in favour of the vascular theory of osteochondritis of the upper femoral epiphysis in children

1. Sixteen injected specimens of human femoral heads and necks, in which a nail or screw had been inserted, were examined. 2. The possibility exists that the fixing agent may interfere with the blood supply of the femoral head. The likelihood of this occurrence is not great. 3. The position of the fixing agent in which vascular damage is least likely is the central area or "neutral zone" of the femoral neck and head

1. Intertransverse fusion in the lumbar spine appears to have many advantages over previously described techniques. 2. The disadvantage of profuse bleeding can be overcome by the use of a Hastings frame and by an operative technique designed to demonstrate constant muscular and articular branches of the lumbar arteries. 3. Coagulation of these vessels by cautery and avoidance of dissection anterior to the plane of the transverse processes ensure that the operative procedure can be carried out with a blood loss averaging less than 500 millilitres

The long-term biological effects of wear debris are unknown. We have investigated whether there is any evidence of cumulative mutagenic damage in peripheral blood lymphocytes of patients undergoing revision arthroplasty of predominantly metal-on-plastic total hip replacements compared with those at primary arthroplasty. There was a threefold increase in aneuploidy and a twofold increase in chromosomal translocations which could not be explained by the confounding variables of smoking, gender, age and diagnostic radiographs. In the patients with TiVaAl prostheses there was a fivefold increase in aneuploidy but no increase in chromosomal translocations. By contrast, in patients with cobalt-chrome prostheses there was a 2.5-fold increase in aneuploidy and a 3.5-fold increase in chromosomal translocations. In six patients with stainless-steel prostheses there was no increase in either aneuploidy or chromosomal translocations. Our results suggest that future epidemiological studies of the putative long-term risks of joint replacement should take into account the type of alloy used in the prosthesis

The acute childhood diseases haematogenous staphylococcal osteomyelitis and septic arthritis were studied concurrently using avian models which closely resemble the human diseases. Ultrastructural studies during the initial stages of bone and joint infection showed that adherence of bacteria to cartilage, bacterial proliferation, cartilage destruction and subsequent bacterial spread along the vascular channels within cartilage were common to both disease processes. Histological studies revealed that transphyseal blood vessels were present in the growing chickens and were a likely explanation for the frequency of the concurrence of acute osteomyelitis and adjacent joint infection following intravenous injection of bacteria. Transphyseal vessels provide a direct connection between the growth plate (physis) and epiphyseal cartilage supplying a route for bacteria to spread from an osteomyelitic focus in the metaphysis to the epiphysis and subsequently to the joint lumen

We perfused 16 human femora with a 50% barium sulphate suspension and studied the intra-osseous vessels by microfocal radiography and histology. There were few anastomoses between the vessels of the greater trochanter and those of the adjacent cancellous bone of the shaft. Ischaemia of the trochanter may contribute to nonunion after trochanteric osteotomy.

1. The treatment of two haemophilic patients with cystic haematoma by radical surgical excision is described.

2. Details are given of their management after operation with the successful use of animal and human antihaemophilic globulin to control bleeding.

3. The literature of cystic haematoma in haemophilia is briefly reviewed and the seriousness of this condition stressed.

Skin cover after below-knee amputation has been extensively discussed. We describe the flaps which are commonly used and discuss their vascular basis in the context of the current knowledge of the fasciocutaneous system. An understanding of this vascular system will enable surgeons to plan and shape flaps for surgical exposure and coverage.