Surgical treatment of neuropathic spinal arthropathy.

Surgical treatment of neuropathic spinal arthropathy is traditionally associated with a high rate of complication. Ten patients were treated surgically using contemporary techniques of spinal instrumentation and fusion which included combined anterior and posterior procedures when appropriate. The etiology of the spinal arthropathy was fracture (8 patients) and tumor (2 patients). Mean postsurgical follow-up was 4 years. Solid arthrodesis was obtained in eight patients. Our recommendations for surgical treatment include (a) posterior segmental instrumentation and fusion for single level Charcot involvement, with bone grafting of the anterior single level defect accomplished through the posterolateral approach; (b) restoration of normal sagittal plane contour, with anterior first stage surgery recommended for rigid kyphosis or multiple level Charcot involvement; and (c) leaving no intercurrent unfused segments between new and old fusions in the area of neurologic deficit. Fusion to the pelvis is not always necessary but late arthropathy may develop between the fused segment and the pelvis.

Treatment of adult spinal deformity with fusion to the sacrum using CD instrumentation.

The effectiveness of Cotrel-Dubousset (CD) instrumentation in long fusions to the sacrum for adult spinal deformity was evaluated in 27 consecutive patients. The CD system provided acceptable correction of kyphosis and scoliosis while restoring or maintaining lumbar lordosis. However, the standard CD pelvic fixation using sacral pedicle and alar screws was problematic. Instrumentation-related complications were frequent (70%). Sagittal and frontal plane balance was difficult to achieve and not consistently maintained. The CD system using sacral pedicle and alar screws in the adult patient does not appear to offer advantages over alternative techniques for achieving arthrodesis to the sacrum for adult deformity.

The osteogenic response to distant skeletal injury.

We tested the hypothesis that when one bone of the skeleton is injured, others experience an osteogenic response. Although similar or related phenomena have been observed previously, the purposes of the study were to determine if this response was reproducible, to characterize it in terms of its magnitude and duration, and to show how it is related to the type of injury sustained. To obtain this information, a model was used in which an intramedullary nail was implanted in the femur and a standard closed fracture was subsequently produced. The osteogenic response was measured by histomorphometry. Eight-four nine-week-old male Sprague-Dawley rats were divided into seven groups of twelve animals each. Groups I and II consisted of control animals in which no injury was produced. In Group-III rats, cortical drilling of the intercondylar notch and piriformis fossa of the right femur was performed, without intramedullary nailing. In Groups IV through VII, half of each group received intramedullary nails only, and in the other half intramedullary nailing was done and a closed transverse diaphyseal fracture was produced. With two different fluorochrome labels, rates of mineral apposition were measured in the left and right tibiae of all animals. The labeling periods differed in each group and were designed to determine when the peak response occurred, how long it lasted, and whether aging during the course of the experiment affected the response.(ABSTRACT TRUNCATED AT 250 WORDS)

Neutral protein-degrading enzymes in experimental fracture callus: a preliminary report.

The process of endochondral fracture healing is biochemically similar to growth plate calcification. Recent studies have identified potentially important roles for proteoglycan-degrading enzymes in the growth plate. The purpose of the study described herein was to identify, in healing fractures, neutral enzyme activities capable of degrading proteoglycans and other matrix proteins. Two sets of 60 male Sprague-Dawley rats underwent the production of closed femoral fractures. Calluses were retrieved at timed intervals, and cell and matrix vesicle fractions were prepared for electron microscopy, neutral peptidase, and alkaline phosphatase assays. In another group of 10 animals, fractions were prepared from 14-day calluses and examined for proteoglycanase activity. In the cell fractions, alkaline phosphatase, alanyl-beta-naphthylamidase, aminopeptidase, and endopeptidase activities showed somewhat parallel distributions peaking at approximately 14-17 days. In the matrix vesicle fractions, similar relative distributions were observed for alkaline phosphatase and endopeptidase. However, here the peak activities occurred up to 3 days later than they did in the cell fractions. Significant proteoglycanase activity was confirmed in both cell and matrix vesicle fractions. These findings are consistent with the hypotheses that (a) neutral peptidases, by virtue of their temporal expression in parallel with alkaline phosphatase, may be involved in preparing fracture callus matrix for calcification; and (b) matrix vesicles may convey certain of these enzymes to sites of both matrix degradation and calcification, since the same activities found in cells are found in matrix vesicles a few days later. The possibility that some of these enzymes are involved in growth factor activation remains to be investigated.

Fracture healing and osteocalcin metabolism in vitamin K deficiency.

Osteocalcin (a vitamin K-dependent, bone-specific protein) is widely accepted as a marker of osteoblastic activity. The present study was conducted to determine if a vitamin K deficiency would affect fracture healing by virtue of an alteration in osteocalcin metabolism. Thirty male Sprague-Dawley rats were divided into two groups. The control group was fed a diet that was lacking in, but offered water replete with vitamin K. The experimental group was fed a vitamin K-deficient diet and was offered water that was lacking in vitamin K. After two weeks, vitamin K deficiency was established in the experimental group as shown by decreased urinary excretion of gamma-carboxyglutamic acid and an elevation of serum prothrombin times to between two to two and one-half times the control values. At this time, a standard, closed femoral fracture was produced. Six weeks later, the animals were killed. The bones were biomechanically tested in torsion. Subsequent to mechanical testing, the calluses were retrieved, and the osteocalcin content and the degree of gamma carboxylation of the osteocalcin in the calluses were measured. The results show that despite significant alterations in the gamma carboxylation of osteocalcin and elevation of prothrombin times to two to two and one-half times the control values, there were no differences in the mechanical properties of the calluses. Furthermore, there were no differences in the content or gamma carboxylation of osteocalcin in these calluses. Apparently, in vitamin K deficiency, fracture callus achieves normal mechanical properties and may have a mechanism for the gamma carboxylation of glutamic acids in osteocalcin despite a substantial depression of this activity in the rest of the body.

The mineral and mechanical properties of bone in chronic experimental diabetes.

The long-term effects of experimentally induced diabetes on bone were studied in eight male Lewis rats, intravenously (i.v.) injected with 65 mg/kg of streptozocin (STZ) and maintained for 12 months. Eight untreated age-matched rats served as controls. In the STZ-treated rats, experimentally induced diabetes was documented by the presence of hyperglycemia at 24 h and at 3 and 12 months. Significantly less weight was gained and less growth occurred in the STZ-treated rats despite careful attention to feeding and hydration. Mineral alterations were detected in the bones of the animals with experimental diabetes. Decreased hydroxyapatite crystal perfection, decreased Ca/P of the ash, and decreased ash content in the tibial metaphyses with increased ash content in the tibial diaphyses, was noted relative to controls. Bone osteocalcin content was increased in the metaphyses of the STZ-treated rats. While absolute measures of stiffness, torsional strength and energy absorption were decreased in the bones of the STZ-treated animals, when torsional strength and stiffness were normalized for differences in both growth and geometry, the normalized stiffness values for the diabetic bones were increased. The results suggest that in experimental diabetes certain aspects of bone mineralization are adversely affected and lead to reduced strength-related properties. However, a compensatory increase in stiffness occurs. The reason for this increase, although not known, may be related to changes in bone crystal structure.

Total hip arthroplasty after renal transplantation. Long-term follow-up study and assessment of metabolic bone status.

Twenty-two patients had 36 total hip arthroplasties for painful osteonecrosis of the femoral head. At a mean of 86 months after operation, a complete follow-up evaluation, including physical examination, was obtained in 24 hips in 15 patients. An additional 12 hips in seven patients were followed by telephone interview and radiographic evaluation. Although most patients experienced improved hip function and symptomatic relief from pain as a result of the operation, 10 hips developed heterotopic bone, 5 hips dislocated after operation, 6 hips failed due to aseptic loosening, and 1 hip developed a deep infection, and one patient died due to pulmonary embolism. Neither sex, preoperative steroid dose, nor postoperative mean alternate-day steroid dose could be related to aseptic loosening. However, histologic examination of transilial bone biopsy specimens (7 patients, 13 hips) revealed steroid-induced osteoporosis, by the presence of hyperosteoidosis (increased unmineralized osteoid) and increased bone resorption. Bilateral hip involvement, osteoporosis, and high turnover skeletal remodelling at the cement-bone interface potentially contributed to a failure rate that was higher in this group than that reported for primary hip arthroplasty for other diagnoses. The existence of steroid-induced metabolic bone disease and preexisting renal osteodystrophy may pose a significant threat to the long-term survival of a total hip implant.

Bilateral rupture of extensor pollicis longus. A case report.

Bilateral rupture of the extensor pollicis longus tendon is a rare entity. Most case studies in the literature have been reported in patients with an underlying systemic condition such as rheumatoid arthritis or following an episode of trauma. An interesting and unusual case is presented and theories concerning etiology, various operative techniques, and recent cases in the literature are discussed.

A case report of calcinosis universalis.

Calcium deposits in soft tissues without previous trauma may represent calcinosis universalis, a condition without systemic manifestations and with laboratory values of blood and urine that are consistently normal. Radiographs reveal areas of calcification with homogenous density, and microscopic examination of these deposits shows foreign body giant cell reaction without capsule formation. In this case of calcinosis universalis, wide excision and lavage of the calcium deposits were temporarily beneficial, but the deposits recurred in this patient.

Abnormalities of the spine in relation to congenital upper limb deficiencies.

A retrospective study was performed to determine the incidence of spinal abnormalities in patients with skeletal defects of the upper extremities. The incidence of scoliosis in the patient population studied was 16%, and spinal abnormalities of all types were present in 18% of the population. Patients with bilateral amelia had a 100% incidence of scoliosis. Those patients with unilateral amelia had a 50% incidence of scoliosis. Patients with ulnar and radial hemimelias had an incidence of scoliosis of 20 and 13%, respectively. The transverse complete and partial hemimelics had an 18% incidence of scoliosis and the phocomelic group had an incidence of 11%. The patient population studied had an increased incidence of scoliosis compared with the general population. The patients with amelia had a particularly high incidence of scoliosis. There was no relationship between the side of the deficiency and the direction of the curve. The age of onset was not found to be related to the progression of the curve. The results of bracing were poor, due to patient rejection of the brace. All patients with upper limb deficiencies warrant close observation throughout growth for the development of scoliosis.

The release of flexion contractures as a prerequisite for the treatment of pressure sores in multiple sclerosis: a report of ten cases.

Ten patients with multiple sclerosis who had severe flexion contractures of the lower extremity ranging from 120 to 180 degrees were treated for large pressure sores. Each patient had at least one pressure sore in the sacral, greater trochanteric, or ischial areas. It was necessary to perform a tendon release procedure of the knee joint prior to addressing the problem of the pressure sores. Prior to treatment all patients were unable to utilize a wheelchair owing to their condition. Subsequent treatment, including development of skin flaps and skin grafts, postoperative casting, and immobilization in a special lamb's wool sling, allowed all 10 patients to improve to the point where they could utilize a wheelchair, with the result that their self-images improved.