Objectives

Activation of the leptin pathway is closely correlated with human knee cartilage degeneration. However, the role of the long form of the leptin receptor (Ob-Rb) in cartilage degeneration needs further study. The aim of this study was to determine the effect of increasing the expression of Ob-Rb on chondrocytes using a lentiviral vector containing Ob-Rb.

From 1981 to 1986 we treated 413 patients for acute spinal-cord injuries. We reviewed 356 patients followed for a minimum of two years of whom 71 (20%) developed heterotopic ossification around one or more joints. Heterotopic ossification occurred more often in male patients (23%) than in female (10%), and was most frequent in the 20- to 30-year age group. It was also more common after injuries of the lower cervical or thoracic spine than after those of the lumbar spine. Patients with severe neurological deficits (Frankel grades A and B) showed significantly more heterotopic ossification but there was no correlation with the number or severity of associated head and limb injuries. Serum calcium levels did not change significantly in either group for 30 weeks after injury, but the erythrocyte sedimentation rate and the alkaline phosphatase level were significantly increased at six weeks in patients with heterotopic ossification

Aims

During revision procedures for aseptic reasons, there remains a suspicion that failure may have been the result of an undetected subclinical infection. However, there is little evidence available in the literature about unexpected positive results in presumed aseptic revision spine surgery. The aims of our study were to estimate the prevalence of unexpected positive culture using sonication and to evaluate clinical characteristics of these patients.

We aimed to assess whether the immunological abnormalities which have been observed in patients with loose total hip replacements (THRs) are present in patients with a well-fixed prosthesis. We examined blood samples from 39 healthy donors, 22 patients before THR and 41 with well-fixed THRs of different types (15 metal-on-metal, 13 metal-on-polyethylene, 13 ceramic-on-ceramic). Before THR, the patients showed a decrease in leukocytes and myeloid cells in comparison with healthy donors, and a prevalence of type-1 T lymphocytes, which was confirmed by the increase in ratio of interferon-γ to interleukin 4. Moreover, patients with metal-on-metal or metal-on-polyethylene implants showed a significant decrease in the number of T lymphocytes and a significant increase in the serum level of chromium and cobalt, although no significant correlation was observed with the immunological changes. In the ceramic-on-ceramic group, leukocytes and lymphocyte subsets were not significantly changed, but a significant increase in type-2 cytokines restored the ratio of interferon-γ to interleukin 4 to normal values. We conclude that abnormalities of the cell-mediated immune response may be present in patients with a well-fixed THR, and that the immunological changes are more evident in those who have at least one metal component in the articular coupling

Aims

Biopsy of the periprosthetic tissue is an important diagnostic tool for prosthetic joint infection (PJI) as it enables the detection of the responsible microorganism with its sensitivity to antibiotics. We aimed to investigate how often the bacteria identified in the tissue analysis differed between samples obtained from preoperative biopsy and intraoperative revision surgery in cases of late PJI; and whether there was a therapeutic consequence.

Aims

Cigarette smoking has a negative impact on the skeletal system, causes a decrease in bone mass in both young and old patients, and is considered a risk factor for the development of osteoporosis. In addition, it disturbs the bone healing process and prolongs the healing time after fractures. The mechanisms by which cigarette smoking impairs fracture healing are not fully understood. There are few studies reporting the effects of cigarette smoking on new blood vessel formation during the early stage of fracture healing. We tested the hypothesis that cigarette smoke inhalation may suppress angiogenesis and delay fracture healing.

We performed a case-control study on the influence of oophorectomy on the development of degenerative spondylolisthesis, including a clinical review and determination of serum oestradiol levels. We also compared the radiological appearance of the lumbar spine at L4/5 in patients with and without spondylolisthesis and with and without oophorectomy. Oophorectomy was a risk factor for degenerative spondylolisthesis with an odds ratio of 7.5 (95% confidence interval, 1.6 to 46). The incidence of degenerative spondylolisthesis in 69 oophorectomised patients was about three times higher than in 69 non-oophorectomised matched control subjects. There was also a difference in spinal variation between oophorectomised and non-oophorectomised patients with spondylolisthesis. A high incidence of sagittal-plane orientation of the L4/5 facet and an increase in pedicle-facet angle were seen in both groups and are typical radiological features of this disease. An increase in lumbosacral angle and in disc-space narrowing was seen only in the non-oophorectomised patients with this condition. Our results suggest that the abrupt decrease in oestradiol level caused by oophorectomy may be a predisposing factor in degenerative spondylolisthesis at L4/5

Aims

Osteoarthritis (OA) is the most prevalent joint disease. However, the specific and definitive genetic mechanisms of OA are still unclear.

1. A case of essential osteolysis is presented, occurring in a young man of eighteen with no known family history and developing progressively from early childhood. The condition was radiologically evident in the elbows, hands and feet, and was accompanied by atrophy of the cancellous bone of the epiphyses of the shoulders and knees. It was also associated with certain abnormalities of the skull and vertebrae. The patient died from a nephropathy of late onset. 2. Examination of the left foot revealed on the radiologically "lysed" bony extremities a very slow process of erosion affecting essentially the epiphysial and metaphysial cortical bone, of a non-inflammatory nature and accompanied by disappearance of the hyaline cartilage. The extremities not radiologically "lysed" showed signs of erosion that were histologically similar but not macroscopically evident; they were accompanied by regressive changes in the hyaline cartilage. 3. There were no signs of renal osteodystrophy or of Sudeck's dystrophy. 4. Post-mortem tests revealed an increase in the seromucoids and failed to reveal the presence of proline in the serum or of proline and hydroxyproline in the urine. 5. The authors discuss the place of this condition among osteolyses in general

1. Metabolic balance studies in two cases of the Fanconi syndrome are presented. 2. The actions of sodium bicarbonate and calciferol on the calcium and phosphorus balance were observed separately in the two cases. 3. The results show that sodium bicarbonate alone corrects acidosis and decreases the loss of calcium in the urine. 4. Calciferol in high dosage will increase intestinal absorption of calcium and phosphorus, but the urine calcium excretion then increases and vitamin D alone does not, therefore, give a positive balance adequate for complete healing and normal growth. 5. Alkalies and calciferol together put these cases into strongly positive calcium and phosphorus balance and promote healing of rickets, osteomalacia and pseudo-fractures. 6. Large doses of sodium bicarbonate in tablet form correct acidosis, do not adversely affect intestinal absorption of calcium, and facilitate accurate dosage and convenient administration. 7. Alkali therapy may lower serum potassium and precipitate symptoms of hypokalaemia in potassium-losing patients. This is thought to have been the cause of symptoms in several cases reported in the literature

We used a rat model in vivo to study the effects of particulate bone cements at the bone-implant interface. A ceramic pin was implanted into the tibiae of 48 rats. Three types of particle of clinically relevant size were produced from one bone-cement base without radio-opacifier, with zirconium dioxide (ZrO. 2. ) and with barium sulphate (BaSO. 4. ). The rats were randomly assigned to four groups to receive one of the three bone cements or normal saline with 2% v/v Sprague-Dawley serum as the control. A total of 10. 9. particles was injected into the knee at 8, 10 and 12 weeks after the original surgery. The animals were killed at 14 weeks and the tibiae processed for histomorphometry. The area of fibrous tissue and the gap between the implant and bone were measured using image analysis. All three types of particle were associated with a larger area of bone resorption than the control. Only in the case of the BaSO. 4. -containing cement did this reach statistical significance (p = 0.01). Particles of bone cement appear to promote osteolysis at the bone-implant interface and this effect is most marked when BaSO. 4. is used as the radiopaque agent

Objectives

Mesenchymal stem cells (MSCs) are of growing interest in terms of bone regeneration. Most preclinical trials utilize bone-marrow-derived mesenchymal stem cells (bMSCs), although this is not without isolation and expansion difficulties. The aim of this study was: to compare the characteristics of bMSCs and adipose-derived mesenchymal stem cells (AdMSCs) from juvenile, adult, and ovarectomized (OVX) rats; and to assess the effect of human parathyroid hormone (hPTH) 1-34 on their osteogenic potential and migration to stromal cell-derived factor-1 (SDF-1).

Aims

Graft infection following anterior cruciate ligament reconstruction (ACLR) may lead to septic arthritis requiring multiple irrigation and debridement procedures, staged revision operations, and prolonged courses of antibiotics. To our knowledge, there are no previous studies reporting on how gentamicin pre-soaking of hamstring grafts influences infection rates following ACLR. We set out to examine this in our study accordingly.

Aims

It is increasingly appreciated that coordinated regulation of angiogenesis and osteogenesis is needed for bone formation. How this regulation is achieved during peri-implant bone healing, such as osseointegration, is largely unclear. This study examined the relationship between angiogenesis and osteogenesis in a unique model of osseointegration of a mouse tibial implant by pharmacologically blocking the vascular endothelial growth factor (VEGF) pathway.

Aims

The best marker for assessing glycaemic control prior to total knee arthroplasty (TKA) remains unknown. The purpose of this study was to assess the utility of fructosamine compared with glycated haemoglobin (HbA1c) in predicting early complications following TKA, and to determine the threshold above which the risk of complications increased markedly.

Sarcoma complicating Paget's disease is uncommon; ninety-five cases have been collected and seven further cases are now reported. Sarcoma probably complicates less than 2 per cent of all cases of Paget's disease. There is a relatively high incidence in males, especially in the sixth decade, whereas bone sarcoma over the age of fifty years without osteitis deformans is rare. Injury is prominent in the history of many cases. Comparison of Paget's sarcoma, "ordinary" bone sarcoma and the bones affected by uncomplicated osteitis deformans reveals some important differences. As to the type of tumour, osteogenic sarcoma is the commonest, but fibrosarcoma and round-cell sarcoma are also frequent. The serum phosphatase is a most useful prognostic guide in a disease with a generally poor prognosis. Magnesium metabolism in relation to bone sarcoma requires further study. Prophvlaxis is based on a clinical suspicion of this complication in Paget's disease, and measures are outlined which may be of assistance. Sarcoma in Paget's bone is highly lethal, but Nature in striking down these old people may have provided us with facts which will ultimately solve problems common to all sarcomas of bone

Aims

To characterize the intracellular penetration of osteoblasts and osteoclasts by methicillin-resistant Staphylococcus aureus (MRSA) and the antibiotic and detergent susceptibility of MRSA in bone.