Subchondral insufficiency fractures of the femoral head.

The aim of this study was to increase awareness of, and to show the variable clinical and radiological features of, subchondral insufficiency fractures of the femoral head. The clinical and radiological findings in 7 patients with subchondral insufficiency fractures of the femoral head were reviewed retrospectively. The diagnosis was confirmed histologically in 4 patients. Radiographs were performed in all patients, MRI in 5 and scintigraphy in 4 patients. Radiographs showed varying degrees of femoral head collapse in 4 patients. In the remaining 3 patients radiographs showed a normal femoral head, regional osteoporosis and focal sclerosis, respectively. Magnetic resonance imaging showed a low-signal band on T1- and T2-weighted images in the subchondral bone adjacent or parallel to the articular surface associated with bone marrow oedema. Scintigraphy showed increased uptake in the femoral head. Insufficiency fractures of the femoral head are easily overlooked or confused with avascular necrosis and, when there is significant joint destruction, osteoarthritis. Unsuspected insufficiency fracture of the femoral head can lead to significant and rapid loss of bone stock in osteoporotic patients waiting for arthroplasty for osteoarthritis. Increased awareness of this condition will hopefully lead to earlier diagnosis and a successful outcome of conservative treatment.

Pacinian corpuscles hyperplasia--an uncommon cause of digital pain.

The authors present two cases of hyperplasia of Pacinian corpuscles, one in the hand and another in the foot. In the hand the corpuscles were located along the radial border of the pulp of the little finger and presented with localised sharp pain. In the foot, it presented as metatarsalgia in association with Morton's neuroma of the second web space. Both patients underwent exploration and excision of the lesion with complete resolution of symptoms.

Vertebral intra-osseous chordoma or giant notochordal rest?

Chordomas of the lumbar vertebral bodies are rare. We report an unusual case of an entirely intraosseous chordoma of the fifth lumbar vertebra treated by vertebrectomy. Conventional radiographs and scintigraphy were normal. The lesion was well visualised by MR imaging, but showed only slight sclerosis on CT. We give our reasons for making a diagnosis of chordoma rather than giant notochordal rest and discuss the problems of management resulting from this diagnostic dilemma.

Radiologically guided bone biopsy: results of 502 biopsies.

PURPOSE: To analyze the results of 502 biopsies over a 19-year period for the purpose of highlighting the results that can be expected from such a large study, with emphasis on needle choice and anesthetic methods. METHODS: The histological, cytological, and microbiological results of 477 patients who had 502 bone biopsies carried out between July 1977 and March 1996 were studied. Less than 5% of patients required second biopsies. There were almost equal numbers of males and females in the group. The lesions were visible radiologically and most of the biopsies were carried out by a single operator. The lesions were classified on their histopathological, cytopathological, and microbiological findings. RESULTS: Tumors accounted for 40% of the biopsies, and infection for 16%. Biopsies which did not yield a "positive" diagnosis accounted for 31%; these included specimens reported as normal, or as showing reactive changes, repair, remodelling, non-specific features, inflammation (but not clearly infective), or no evidence of malignancy or inflammation. Less than 4% of biopsies were incorrect, and some of these were re-biopsied. CONCLUSION: Bone biopsy is a valuable technique for positive diagnosis of malignancy or infection, as it enables a definitive plan for treatment and management of patients to be established. Exclusion of serious pathology is almost equally important. In principle, any osseous site can be biopsied using fluoroscopic or computed tomographic guidance. Care in the biopsy technique and selection of the bone needle is required.

Innervation of the spondylolysis "ligament".

SUMMARY OF BACKGROUND DATA: Spondylolysis of the lower lumbar vertebrae is a non-united childhood fracture of the arch of the vertebra, persisting into adult life. Symptoms of disabling low back pain appear in a minority of patients, usually for the first time in adulthood. This pain is considered to arise from several separate sources, one of which may be the spondylolysis ligament. STUDY DESIGN: The innervation of the ligament has been investigated immunohistochemically. METHODS: Specimens from eight patients were divided longitudinally for histology including hematoxylin and eosin, toluidine blue, and elastic van Gieson. Histochemistry involved immunostaining for the neuropeptides: protein gene product, calcitonin gene related peptide, substance P, vasoactive intestinal peptide, and the c-flanking peptide of neuropeptide Y. RESULTS: Immunoreactivity to calcitonin gene-related peptide, the c-peptide of neuropeptide Y, and vasoactive intestinal peptide was identified in the ligament or in the adjacent adipose tissue. CONCLUSION: The movement that the ligament allows at the fracture site may result in stimulation of the nerve endings both in the ligament and in the surrounding soft tissue.

Osteopenia in systemic mastocytosis: natural history and responses to treatment with inhibitors of bone resorption.

Studies of a 63-year-old woman with osteopenia due to systemic mastocytosis are reported. Delay in making the diagnosis and the occurrence of coincident medical problems meant that radiographs during a 12-year period were available for study. Skeletal symptoms began 20 years after the skin lesions of mastocytosis first appeared, but once established bone loss was rapid, particularly from cortical bone (estimated at 3.75% pa). Biochemical and histological measurements indicated a "high turnover" bone disease and treatment with inhibitors of bone resorption was assessed. Oral, but not intravenous, clodronate was effective in reducing bone turnover as judged by falls in hydroxyproline excretion (p less than 0.01) and serum alkaline phosphatase (p less than 0.01). Mithramycin and chlorambucil were ineffective. Clodronate may be beneficial in arresting bone loss in this disorder.

Plasma cell balinitis of Zoon.

Superficial lesions of the glans penis can pose diagnostic difficulties. Plasma cell balanitis is such a condition and it may be confused clinically with erythroplasia of Queyrat. It is unresponsive to topical medication and curable only by circumcision.

Mesenchymal hamartoma of the liver--report of an unusual case.

An 8 year old girl presented with gross hepatomegaly, anaemia and pyrexia unresponsive to antibiotics. At laparotomy a cystic mass 19 cm in diameter was found arising from the liver. The cyst contained 2.4 litres of changed blood and an abscess cavity filled with thick pus was present in the cyst wall. Histological examination showed the appearances of a mesenchymal hamartoma of the liver, a rare diagnosis at this age. This case is unusual as mesenchymal hamartoma has not been previously reported presenting with pyrexia and anaemia as well as hepatomegaly.

Papillary adenocarcinoma of lung with psammoma bodies: report of a case derived from type II pneumocytes.

A 52-year-old woman underwent thoracotomy for the removal of a mass in the middle lobe of the right lung. Light microscopy showed a tumour with the morphology of a papillary adenocarcinoma with numerous psammoma bodies. Electron microscopy revealed the tumour cells to possess the lamellated intracytoplasmic inclusions characteristic of normal and neoplastic type II pneumocytes. Psammoma bodies have not previously been reported in type II cell carcinoma of the lung. Alveolar cell carcinoma should be considered in the differential diagnosis of a papillary adenocarcinoma with psammoma bodies occurring in the lung.

Dyspnoea and thoracic spinal deformation in rats after oral prizidilol (SK&F 92657-A2).

Prizidilol (SK&F 92657-A2), an anti-hypertensive agent, has undergone a range of prescribed toxicity studies required for the investigation of possible adverse drug effects. During the second year of the 2-year rat oral study, a variety of symptoms were exhibited by males receiving 1600 mg of the compound day-1kg-1 by gavage. These animals became lethargic, slouched and developed dyspnoea which became progressively more severe during the course of the study. Necropsy of the affected rats revealed severely haemorrhagic lungs, cardiac hypertrophy and lordosis of the spine into the thoracic cavity. At the 2-year terminal kill, a proportion of the male rats receiving 100 and 400 mg of prizidilol day-1kg-1 were identified with similar but less severe spinal deformation. No female was found with spinal changes but all the rats receiving prizidilol showed haemorrhagic lungs and enlarged hearts. The lordosis of the affected males was always confined to the thoracic spine and this, along with the cardiac hypertrophy, presumably led to marked reduction in the volume of the thoracic cavity, inducing the dyspnoea. Thoracic vertebral body damage, possibly a precursor to the spinal deformities, was found in male rats from both drug-treated and control groups. The nature of the spinal lesion is at present under investigation.

Bone metabolism in acute parathyroid crisis.

Studies on bone metabolism described in a fatal case of acute parathyroid crisis, occurring in a 48-year-old woman in whom serum immunoreactive parathyroid hormone levels were very high, and a 5 g parathyroid adenoma was found at operation. The histological and biochemical findings suggested a massive and acute increase in bone resorption. There was, however, no evidence of any compensatory increase in bone formation, indicating that acute parathyroid crisis is characterized by a marked dissociation between bone resorption and formation. It is suggested that a sudden fall in oestrogen levels may contribute to the pathogenesis of this disorder.

Sex hormones and skin collagen content in postmenopausal women.

Skin biopsy specimens were taken from 29 postmenopausal women who had not been given hormone replacement therapy and from 26 women who had been treated with oestrogen and testosterone implants for two to 10 years. The mean hydroxyproline content and therefore the mean collagen content in the skin was found to be 48% greater in the treated than the untreated women, who were matched for age. This difference was significant (p less than 0.01). The implication of this finding is that oestrogen or testosterone, or both, prevents the decrease in skin collagen content that occurs with aging and protects skin in the same way as it protects bone in postmenopausal women.

Jamshidi needle biopsy of bone lesions.

The technique and advantages of using a Jamshidi needle for skeletal biopsies are described, together with the results of 50 consecutive biopsies. A combined clinical, radiological and pathological approach to the lesions can provide the diagnosis in the majority of patients.

Mean wall thickness and formation periods of trabecular bone packets in idiopathic osteoporosis.

The mean wall thickness (MWT) and duration of formation periods (sigma f) of trabecular bone packets have been measured in iliac crest biopsies following double tetracycline labeling from 9 women having primary osteoporosis, with vertebral crush fractures and reduced trabecular bone volume (TBV), and 9 age- and sex-matched controls. The MWT of the osteoporotic biopsies was significantly less than that of the controls and was negatively correlated with age in the latter. There was also a positive correlation between MWT and TBV in the controls but not in the osteoporotics. Sigma f, in days, showed a tendency to decline with age in the control biopsies and was further decreased in the osteoporotic patients. These results suggest that a major contribution to the negative skeletal balance existing in both primary osteoporosis and physiological osteopenia is a decrease in bone formation, caused by a reduction in the life span of the osteoblastic population at the basic multicellular unit (BMU) level.

Hormone replacement therapy in the menopause: a suitable animal model.

Female CBA mice, aged 11 months, were treated cyclically with oral ethynyl oestradiol or oestrone sulphate for 3 months. The ovaries of all animals appeared to be atrophied. Target tissues throughout the genital tract showed a response to both oestrogens. Electron microscopy of both the endometrium and the urothelium demonstrated morphological changes characteristic of increased cellular metabolic activity in the treated mice. Endometrial hyperplasia developed in both treatment groups but more pronounced epithelial changes occurred with oestrone sulphate. This hyperplasia was accompanied by a doubling in the number of uterine cytoplasmic oestrogen receptors. A 50% fall in serum levels of luteinizing hormone in the treated mice revealed that the hypothalamic-pituitary system was still intact. Both oestrogens improved skeletal balance by changes in cortical-endosteal bone remodelling. The results suggest that the CBA strain of mouse is a suitable model for the study of the human climacteric and its response to hormone replacement therapy.