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Biomedical subjects

N Halperin

Publications and source records attributed to N Halperin.

At least 19 recordsLinked to original sources
PubMed1992

Neuropeptidergic innervation of intramuscular hemangiomas.

Intramuscular hemangiomas are idiopathic lesions which are either tumoral or developmental in origin. A close association of abnormal blood vessels with nerve fibers is found and may suggest that nerves have a primary inciting role in the development of these lesions. In the current study, the number of nerve fibers in different zones around the tumors, as well as the type of neuropeptides present in these fibers, was quantitatively assessed by computer-assisted image analysis of immunohistochemical staining of histological slides. The number of nerve fibers as determined by positive staining by anti-protein S-100 antibodies was found to be elevated in the immediate vicinity of the abnormal blood vessels. The density of the nerve fibers rapidly declined with increasing distance from the hemangiomas, reaching normal values at distances of over 2 mm. Furthermore, hemangiomas contain a significantly higher number of calcitonin gene-related peptide (CGRP), substance P, and Met-enkephalin-positive fibers. The most significant rise in number is that of CGRP-positive fibers. This neuropeptide is a known mitogen, which could be responsible for the growth of the hemangiomatous blood vessels. Substance P is a nociceptive neurotransmitter and its presence can explain the pain which often accompanies even tiny intramuscular hemangiomas.

Adolescent↗
PubMed1992

Medial epicondylectomy in cubital tunnel syndrome: an electrodiagnostic study.

Prospective analysis of 27 medial epicondylectomies in 22 patients with McGowan grade I ulnar neuropathy demonstrated an improvement in clinical symptoms. In all patients a N.C.V. study, in which compression of the ulnar nerve at the cubital tunnel was evident, has been a prerequisite for operation. Conduction velocity across the cubital tunnel averaged 48% of normal (26.4 +/- 8.7 metres per second) preoperatively and increased to 85% of normal (46.7 +/- 9.7 metres per second) postoperatively. A preoperative N.C.V. study allows the achievement of a high success rate, especially in the less well clinically defined group of patients with grade I neuropathy (subjective complaints without any objective signs of muscle atrophy). Medial epicondylectomy is safe and predictable in the treatment of cubital tunnel syndrome.

Adult↗
PubMed1992

Restoration of pinch in ulnar nerve palsy by transfer of split extensor digiti minimi and extensor indicis.

Subcutaneous transfer of the ulnar slip of the extensor digiti minimi (EDM) to the adductor tubercle across the dorsum of the hand restores pinch, and index finger abduction is reproduced by re-routing extensor indicis proprius around the thumb extensor tendons. Six patients with post-traumatic ulnar palsy have been treated by this method with a minimum follow-up period of 40 months. Pinch was improved from an average of 5% to 40-50% of the normal side, and index abduction to 30-40%. There was no donor morbidity.

Adult↗
PubMed1992

The use of the transpillar posterolateral approach to resect cervical osteoid osteomas: operative technique and results.

Osteoid osteomas located in the cervical spine are a rare cause of cervical and shoulder pain. However, successful diagnosis of these tumors has become more frequent in the recent years. This is due to more available diagnostic modalities as well as to physician awareness of the possibility that such lesions can cause cervical pain syndrome. Resection of osteoid osteomas located close to the vertebral artery is often technically difficult, and poses significant risk to the patient. We describe resection of such tumors using a posterolateral transpillar approach in three patients. The advantage of this approach is the direct and relatively easy visualization of the tumor, without the need for an extensive dissection. The stability of the cervical spine is not compromised by this approach. However, extension of the operative field is difficult, should the need arise.

Cervical Vertebrae↗
PubMed1992

Anterior compartment syndrome of the thigh in athletes--indications for conservative treatment.

Anterior compartment syndrome of the thigh resulting from blunt contusion without an accompanying fracture is rare. The treatment advocated for it by most authors has been surgical. However, because wound infection rates are high and loss of knee range of motion is frequent, we considered conservative treatment in selected patients. Six athletes who developed an anterior thigh compartment syndrome shortly after sustaining a blunt contusion to the quadriceps with an accompanying massive hematoma were studied prospectively. Tissue pressure, renal function, and creatinine phosphokinase (CPK) levels were closely monitored. Fasciotomy was not performed, despite sustained pressure elevations above 50 mm Hg. Neurologic function was not affected. At follow-up examination 1 year later, no limitation of joint motion nor weakness of the quadriceps were observed. Thus in selected young patients in whom an isolated anterior compartment syndrome of the thigh occurs, conservative treatment yielded results superior to fasciotomy.

Adult↗
PubMed1992

Devascularization of the anterior cruciate ligament by synovial stripping in rabbits. An experimental model.

In rabbits, synovial stripping of the anterior cruciate ligament was performed, and histologic and mechanical changes were followed up to 2 months. The operation did not immediately affect the strength of the ligament or its histological structure. However, a gradual deterioration of mechanical properties, associated with collagen necrosis and an ineffectual reparative response, was evident. Thus, synovial stripping of the ligament with the attendant concomitant devascularization leads to ligamentary insufficiency despite the lack of structural damage to the ligament by the contusion itself.

Animals↗
PubMed1991

Abductor pollicis longus tendon arthroplasty of the trapezio-metacarpal joint: surgical technique and results.

Tendon interposition resection arthroplasty of the trapezium is a valuable tool in treating osteoarthrosis of the first carpometacarpal joint. A previously unreported modification of such an operation is described in which a part of the abductor pollicis longus tendon is used as an interposition material. This technique was employed in a series of thirty-nine thumbs. After a minimal follow-up period of 2 years, the results of the operation are graded excellent in 48% of the patients, good in 35%, and average in the rest. Grip strength, as well as pinch strength, is about three quarters of the normal average. No patient needed a further operation.

Aged↗
PubMed1991

Active knee joint subluxation: its influence on the prognosis of ligament reconstruction.

Voluntary subluxation of the knee, known as active pivot shift, can be observed in a minority of patients with anterior cruciate ligament deficiency knees. We compared a group of 7 patients exhibiting voluntary subluxation of the knee joint with a group of 61 patients undergoing a similar operative procedure who did not demonstrate this sign. Despite similar age and similar operative procedures, the former group remained handicapped and regained the ability to subluxate the knee. We conclude that patients who exhibit voluntary subluxation of the knee joint are poor candidates for knee-ligament reconstruction.

Adult↗
PubMed1990

Regenerating hyaline cartilage in articular defects of old chickens using implants of embryonal chick chondrocytes embedded in a new natural delivery substance.

Partial and full thickness defects were created mechanically in articular cartilage and subchondral bone of the tibiotarsal joint condyles of 3-year-old chickens. The wounds were then repaired using embryonal chick chondrocytes embedded in a new biocompatible, hyaluronic acid-based delivery substance. Controls were similarly operated on but received either no treatment or implants of the delivery substance only. Animals were killed from 1 week to 6 months postoperatively. Sections from the two groups were examined and compared macroscopically, histologically, and histochemically. Results of 6-month follow-up showed that only the defects of the experimental chickens were completely filled with reparative hyaline cartilage tissue, with no signs of inflammation or immunologic rejection. Initially the entire defect cavity, whether partial thickness or full thickness up to the deep regions in the subchondral bone, was filled with cartilaginous reparative tissue. Relatively rapid maturation occurred under the tidemark; chondrocytes hypertrophied, were invaded with vascular elements and ossified. In the superficial areas, the reparative tissue remained cartilaginous and matured as typical hyaline cartilage tissue. These results indicate that aged chicken cartilage and its accompanying thin and spongy osteoporotic bone offer a favorable host environment for embryonal cell implants.

Animals↗
PubMed1990

Hereditary chondrocalcinosis in an Ashkenazi Jewish family.

A hereditary chondrocalcinosis is described for the first time in an Ashkenazi Jewish kindred. Of 34 family members in five generations, seven had medical history suggesting the disease. Five of 25 members of generations III-V had direct evidence for their disease. Characteristically, symptoms started at a fairly early age (third decade) while radiological evidence of chondrocalcinosis was delayed to the fourth decade. Joints commonly affected were knees, wrists, and elbows. The course was chronic with acute, exercise induced exacerbations.

Adult↗
PubMed1989

Spondyloepiphyseal dysplasia associated with progressive arthropathy. An unusual disorder mimicking juvenile rheumatoid arthritis.

A family is presented with three affected siblings suffering from a rare form of spondyloepiphyseal dysplasia with progressive arthropathy affecting most joints of the body except for the craniofacial skeleton. This syndrome, probably of autosomal recessive inheritance, clinically presents diffuse and chronic joint involvement and should be differentiated from juvenile rheumatoid arthritis and other rheumatic disorders.

Adolescent↗
PubMed1989

Fate of allogeneic embryonal chick chondrocytes implanted orthotopically, as determined by the host's age.

Chondrocytes derived from chick embryos can be successfully implanted in defects of adult chick articular cartilage surfaces. Such implants thrive in their implantation site and create a new articular surface. The chondrocytes mature and hypertrophy in the orthotopic site without invoking an immune response. Eventually a steady state is reached in which mature chondrocytes resurface the defect while in the deeper areas spongy bone replaces the hypertrophic chondrocytes. Time schedules of these repair events have been studied in hosts of different ages. We compared 4-month-old chicks with 3-year-old chickens. The embryonal chondrocytes implanted in the latter group underwent an accelerated aging process. The defects were completely filled-up after 1 month as compared with 2-3 months in the younger age group. Endochondral ossification in the older group was evident as early as 2 months post implantation and was completed after 6 months. This contrasts with the situation in the younger group where the chondrocytes only began to hypertrophy after 6 months. At this stage endochondral ossification was hardly seen at all. A unique response to the cartilaginous implants is seen in the old group only in the vicinity of the reparative tissue, accumulation of hematopoietic centers. This study seem to indicate that the host's environment affects the "biological clock", i.e. rate and degree of aging of the implanted cells, as well as their matrices.

Age Factors↗
PubMed1989

An overlapping pubic dislocation treated by closed reduction: case report and review of the literature.

An overlapping dislocation of the symphysis pubis is a rare injury caused by either side-to-side compression or hyperextension. We hereby describe a case of such injury sustained during parachuting and reduced by closed means. This case appears to be the first described in the literature where no damage to the urogenital tract was observed. The patient is asymptomatic 1 year later.

Adult↗
PubMed1989

Multicentric giant-cell reparative granuloma. A case in the foot.

A case of multicentric giant-cell reparative granuloma in the foot of a 17-year-old boy is reported. Initially, there was a calcaneal lesion and 6 months later, three additional lesions in the forefoot. The calcaneal lesion was treated by curettage and bone grafting, and those in the forefoot by wide excision. The patient has now been free of disease for 18 months.

Adolescent↗
PubMed1989

Nocardia asteroides infection of an Austin-Moore hemiarthroplasty in a nonimmunocompromised host. A case report.

A case of Nocardia asteroides infection of a hip prosthesis in a nonimmunocompromised patient is presented. The infection developed soon after the operation, and did not respond to empiric treatment by multiple antimicrobial drugs. Reoperation and removal of the prosthesis was necessary. The authors found no previous cases of nocardiosis complicating arthroplasty reported in the literature.

Aged↗