Stress fracture of the tibia after arthrodesis of the ankle or the hindfoot.

We studied twelve patients who had a stress fracture of the tibia and one patient who had a stress fracture of the fibula after arthrodesis of the ankle or the foot. A second stress fracture subsequently developed in two patients. All but two patients were managed non-operatively, and the fractures healed uneventfully. One patient who was managed operatively had a below-the-knee amputation to treat a painful non-union of a tibial fracture, and the other had interlocking intramedullary nailing for a displaced fracture. All but one of the arthrodesis sites had fused before the stress fracture occurred. All of the stress fractures that occurred after arthrodesis of the ankle were in the middle and distal aspects or the distal aspect of the tibia, while those that occurred after triple arthrodesis were in the distal aspect of the fibula or the medial malleolus. Although six of the thirteen patients still had uncorrected alignment and deformity after the arthrodesis, optimum alignment after the arthrodesis did not preclude the occurrence of a stress fracture. We conclude that stress fracture must be considered in the differential diagnosis of pain months or even years after solid fusion at the site of an ankle or triple arthrodesis.

Centrocentral anastomosis with autologous nerve graft treatment of foot and ankle neuromas.

Painful neuromatas in the foot and around the ankle can be difficult to treat. Five patients of clinically and histologically proven neuromas underwent centrocentral union with autologous transplantation. Three patients had previous toe amputations involving multiple operations. One patient had failed multiple operative treatments for Morton's neuroma in his 3rd web space. One patient had a neuroma in his superficial peroneal nerve caused by a gun shot wound. All patients but one showed definitive subjective and objective improvement after centrocentral union with the interposed autologous nerve graft. The patient with "recurrent" Morton's neuroma had the least improvement. This technique can be recommended as an alternative for the prevention of painful stump neuromata.

Effect of serum amyloid A, HDL-apolipoprotein, on endothelial cell proliferation. Implication of an enigmatic protein to atherosclerosis.

The possible contribution of apo-HDL serum amyloid A (SAA) to the protective effect of HDL against atherosclerosis was studied by evaluating its effect on bovine aortic endothelial cell (BAEC) proliferation. Our results suggest that human SAA, both purified and recombinant, in concentrations relevant to mild acute phase events, significantly inhibit endothelial cell proliferation in a dose-dependent manner (e.g., 50 micrograms/ml causes approximately 88% inhibition; p < 0.001). This inhibition was attenuated by addition of fibroblast growth factor (FGF), which antagonized the SAA-mediated effect. As levels of TNF may be highly elevated during the acute phase response, its effect on BAEC proliferation was evaluated and found, at concentrations of > 1 pg/ml, to be substantially inhibitory Co-incubation of cells with both SAA and TNF was inhibitory, albeit neither additive nor synergistic. FGF antagonized the effect of both proteins. Amyloidic deposit (AA, i.e. SAA 1-76), derived from pathological proteolysis of SAA, practically retains the inhibitory activity (e.g. 50 micrograms/ml causes approximately 66% inhibition; p < 0.001) but apparently lacks the regulatory site towards FGF. In contrast to the above inhibitory effect, synthetic SAA-related peptide corresponding to the sequence 29-33 of SAA enhances BAEC proliferation (50 micrograms/ml causes approximately 64% increase; p < 0.001). The present data, coupled with our previous observations in which SAA was found to induce endothelial PGI2 formation and to inhibit overproduction of PGI2 by TNF and LPS as well as platelet aggregation, may suggest that SAA contributes to the protective effect of HDL against atherosclerosis. This, by means of its modulatory effect on endothelial cell and platelet activation, primarily in the presence of other regulatory proteins. SAA-derived peptides may, potentially, be used as therapeutic agents in the treatment of atherosclerosis and cardiovascular diseases.

Decrease in bone levels of 1,25-dihydroxyvitamin D in women with subcapital fracture of the femur.

In a previous study we were able to show that in women over the age of 45 the level of 1,25-dihydroxyvitamin D (1,25(OH)2D) in bone, but not in serum, is significantly reduced when compared with younger women. In the present study we measured the concentration of 1,25(OH)2D in sera and bones of 19 female patients with subcapital fractures of the femur, mean age 78 +/- 2 years. We were able to show that serum levels of 1,25(OH)2D were within the normal range, while bone levels were markedly reduced compared to levels in femoral bone obtained from young female cadavers or to the previously reported levels in non-osteoporotic elderly women. Thus, reduced levels of 1,25(OH)2D in bones of elderly women may lead, together with other factors, to subcapital fractures.

Management of pyogenic vertebral osteomyelitis with spinal cord compression in the elderly.

Five elderly and debilitated patients presented with compressive myelopathy due to pyogenic spondylitis. All had undergone surgery which consisted of eradication of the infected tissue via an anterior approach followed by primary bone graft. Supplementary antibiotic treatment was determined by intraoperative bacteriological culture. This aggressive approach, disregarding the patients' advanced age and poor general medical state, resulted in total resolution of the neurological deficit and the patients' return to their preoperative everyday activity.

Parosteal lipoma of the proximal radius: a report of five cases.

Parosteal lipoma of the proximal radius is a benign, slow-growing tumor. It may cause compression of either the posterior interosseous or the superficial branch of the radial nerve. Surgical excision usually leads to complete recovery. Five cases of parosteal lipoma of the proximal radius are presented. X-ray films demonstrated a radiolucent mass in contact with the radius. Two patients had signs of posterior interosseous nerve compression, and two showed signs of superficial radial nerve compression. In one case the lipoma surrounded an exostosis arising from the proximal radius. The tumors were excised in four patients. The three patients with neurologic involvement recovered fully. One patient refused surgery, and posterior interosseous nerve paralysis developed.

Sarcoidosis masquerading as a parathyroid adenoma.

Two patients presented with a presumptive diagnosis of hyperparathyroidism. Surgically excised "parathyroid glands" were found to be, in fact, large lymph nodes with sarcoid granulomata. In one patient, the preoperative localization of the "parathyroid adenoma" was based on scintigraphy (thallium-technetium subtraction imaging) and sonography procedures. The differential diagnosis of hypercalcemia, and positive scintigraphy-sonography studies, must include sarcoidosis in an isolated cervical lymph nodes.

Decrease in bone level of 1,25-dihydroxyvitamin D in women over 45 years old.

The most active metabolite of vitamin D is 1,25-dihydroxyvitamin D [1,25(OH)2D]. Its level in the bone may play a role in the pathogenesis of metabolic bone diseases such as osteoporosis. To assess this, and to see whether there is correlation between serum and bone levels, we studied serum and bone samples taken from 43 patients (18 men and 25 women) undergoing different orthopedic procedures. Patients were studied according to sex and age groups (less than 45 years, 46-60 years, greater than 61 years). Serum level of 1,25(OH)2D was found to be 29.7 +/- 2.61 pg/ml (mean +/- SEM) for women, 32.2 +/- 3.86 pg/ml for men, and 30.7 +/- 2.18 pg/ml for the group as a whole. No significant statistical differences were found among age subgroups in either sex or between sexes. Bone level of 1,25(OH)2D was found to be 31.5 +/- 4.46 pg/g for women, 26.5 +/- 3.06 pg/g for men, and 29.4 +/- 2.81 pg/g for the entire group. No significant statistical difference was found between the age subgroups for men. However, the level of 1,25(OH)2D was found to be higher in the group of younger women (less than 45 years) compared with the older women (46-60 years and greater than 61 years) (P less than 0.005).

Salmonella paratyphi C osteomyelitis: report of two separate episodes 17 years apart.

Osteomyelitis secondary to salmonella infection is well documented in the literature. Infection in more than one focus has also been described. To the best of our knowledge this is the first report of recurrent osteomyelitis in a normal host (a 35-year-old man) with the same organism (S. paratyphi C) in different sites 17 years apart.

Successful high-dose calcium treatment of aluminum-induced metabolic bone disease in long-term home parenteral nutrition.

A patient who developed severe metabolic bone disease is presented. He had received long-term home parenteral nutrition (HPN) following extensive small bowel resection after mesenteric vein thrombosis. Bone disease caused by aluminum intoxication had components of osteomalacia and low-turnover osteoporosis. Aluminum was detected at the surface of mineralized bone and was elevated in the serum, resulting in a positive deferoxamine infusion test. One year of treatment with high doses of calcium (up to 24 mEq per day) significantly diminished the patient's bone pain, increased the serum levels of calcium, abolished aluminum deposits in the mineralized trabecula, improved bone formation, and increased trabecular bone volume as assessed by repeated histomorphometric analysis.

Migratory multiple bone involvement in a patient with systemic mastocytosis.

A young patient with severe generalized osteopenia and multiple compressed vertebral fractures caused by systemic mastocytosis is presented. Extensive clinical, laboratory, and pathologic examination showed the involvement of the skeleton alone. Follow-up bone scintigraphy with Tc-99m MDP during a period of 6 years demonstrated migratory multiple axial lesions. These results suggest that Tc-99m MDP imaging is an accurate detection of the activity of the disease.

Osteoporosis as the sole presentation of bone marrow mastocytosis.

Three (young) adults with severe generalized osteopenia and vertebral compression fractures were studied. Extensive clinical and laboratory investigations were not contributory. Undecalcified bone biopsies demonstrated multiple mast cell granulomas in the marrow in two patients and numerous mast cells diffusely distributed throughout the bone marrow in the third patient. Mast cells may serve as a pathogenic agent in osteoporosis. Therefore, we conclude that isolated skeletal mastocytosis without clinical evidence of mast cell mediator release should be sought in the evaluation of a patient with unexplained severe bone loss.

Biochemical and biomechanical properties of avian callus after local administration of dihydroxylated vitamin D metabolites.

In vitamin D-fed chicks 1,25-dihydroxyvitamin D3 and 24,25-dihydroxyvitamin D3 were implanted into experimentally-produced fractures of the mid-tibia. The mechanical and biochemical properties of the tibia were evaluated for two weeks, including torsion tests, measurement of alkaline phosphatase activity, 45Ca incorporation, and Ca2+ content. Both dihydroxylated metabolites of vitamin D3 had a direct effect on endochondral bone formation. 24,25(OH)2D3 strengthened the callus, and raised alkaline phosphate activity in the first seven days after fracture. 1,25(OH)2D3 decreased the strength of the callus concomitant with a reduction in 45Ca incorporation. It is suggested that local application of 24,25(OH)2D3 into fractures may accelerate healing and prevent non-union.

Proteoglycan synthesis in vitamin D-deficient cartilage: recovery from vitamin D deficiency.

Vitamin D appears to be required for mineralization of skeletal elements. There is also evidence that cartilage proteoglycans may be involved in the regulation of mineralization. Previous studies have shown an alteration in the structure of the proteoglycans of the epiphyseal growth cartilage as a result of the decrease in serum calcium related to deficiency of dietary vitamin D. Vitamin D deficiency also induces a thickening of the epiphyseal growth plate presumably because of the inhibition of maturation of the growth plate chondrocytes. In order to compare the effect on proteoglycan structure with that on growth plate morphology, the proteoglycans of healing epiphyseal cartilage were characterized. The results indicate that, consistent with previous data, in vitamin D-deficient hatching chicks, the proteoglycans of the growth cartilage, but not of the articular cartilage, are smaller in monomer size with slightly smaller chondroitin sulfate chains whose sulfation pattern is unaltered. Sternal cartilage proteoglycans are unaffected. During recovery from vitamin D deficiency, the proteoglycans isolated from the growth cartilage are still not completely normal one day after supplementation with vitamin D, but are indistinguishable from normal by four days. In addition, the results conflict with those of a previous study in which only growth cartilage of hatchling chicks, not sternal or articular cartilage, was reported to synthesize large proteoglycans. Instead, all of these cartilages in the normal chicken have been found in this study to produce large proteoglycans of a size typical for mammalian cartilage and embryonic chick cartilage.