Biomedical subjects

H Resch

Publications and source records attributed to H Resch.

97 records · Page 6Linked to original sources

PubMedDate not supplied

Dynamic stabilization of winging scapula by direct split pectoralis major transfer: a technical note.

A new technique of split pectoralis major tendon transfer (sternal head) for symptomatic scapular winging is shown. Whereas other authors use a lengthening with autogenous grafts, we prefer a direct attachment of the split pectoralis major tendon. With the use of an anterior and a posterior incision, the tendon of the sternal head of the pectoralis major is mobilized and transferred directly to the inferior angle of the scapula. An anatomic study shows that the pectoralis major muscle usually seems to be suitable for this procedure. Direct transosseous fixation of the transferred split pectoralis major tendon appears to be an excellent operation for correcting winging scapula without the necessity of an autogenous graft and concern over stretching or tearing of the graft extension.

Cadaver↗

PubMedDate not supplied

Reconstruction of the valgus-impacted humeral head fracture.

Between 1985 and 1991, 22 patients (average age 52 years, range 26 to 65 years) with severely impacted humeral head fractures were operated on with the aim of preserving the humeral head. All 22 cases showed no significant lateral displacement. Thus it was assumed that the periosteum leading medially to the humeral head was intact and that the vessels passing through the periosteum would ensure survival of the humeral head segment. All patients underwent treatment with open reduction. The impacted segment of the humeral head was raised, the tuberosities were relocated, and the void was filled with chips of cancellous bone. This procedure provided fixation with minimal osteosynthesis. At follow-up evaluation (minimum 18 months, average 36 months) one patient had sequestration of the head segment, and another patient had clinically asymptomatic partial necrosis. None of the remaining 20 patients showed signs of necrosis. Slight arthrosis was present in two patients, and moderate arthrosis was present in one. A correlation was found between the functional result and the quality of reduction. Where anatomic reconstruction had been successful, the long-term functional result was almost identical with the nontraumatized side.

Adult↗

PubMedDate not supplied

Structural analysis of an offset-keel design glenoid component compared with a center-keel design.

Many different designs of glenoid prostheses have been developed in an attempt to reduce the loosening rates and improve the prognosis of total shoulder arthroplasty. This study investigated a design in which the keel is positioned anterior to the central plane of the component, an offset-keel design. The primary purpose of anterior location of the keel is to avoid contact between the keel and the cortical bone surface. However, anterior placement of the keel also situates it more directly under the line of action of the contact force in abduction; this has the possible advantage of reducing the bending stress on the cement mantle. Our purpose was to establish whether an offset-keel design reduces the cement stresses below those obtained with conventional central-keel designs. A computed tomography-based finite element model of the glenoid region is used and dynamic loading for 0 degrees to 180 degrees in both flexion and abduction is simulated with the use of data from van der Helm (J Biomech 1994;27:527-50). Finite element analyses are carried out for both the normal and the rheumatoid arthritic case. For the rheumatoid arthritic joint, a Larsen grade IV type destruction is reproduced and proximal subluxed loads are applied, associated with a deficient rotator cuff for 0 degrees to 180 degrees in flexion and abduction. Results predict that the cement mantle in the offset-keel design is much less stressed compared with that in the center-keel design for the maximum glenohumeral joint load in abduction for both the normal and the rheumatoid arthritis case. In flexion the offset-keel design still has lower cement stresses even though the load is acting on the opposite side of the glenoid cup from the keel; one explanation for this is that insertion of the offset keel involves removal of the lower stiffness cancellous bone, leaving the glenoid component flanges to be supported by the stronger bone remaining in the glenoid cavity. From a biomechanical point of view, the advantages of an offset-keel design would appear to be considerable.

Biomechanical Phenomena↗

PubMedDate not supplied

The impact of a senior dancing program on spinal and peripheral bone mass.

Because activity and regular exercise are important factors to maintain general good health in senior citizens, we investigated whether senior dancing has any effect on peripheral or lumbar bone density. We performed a prospective study over a12-mo period on bone density at a spinal and peripheral measuring site in 28 female senior members (mean age: 67 +/- 2 yr) of a dancing group in Vienna. Lumbar bone mineral density was assessed by quantitative computed tomography (qCT) and radial bone density by single photon absorptiometry of the distal forearm. The mean training time per week was 3.2 +/- 0.8 h. In the entire group of female dancers, no significant effects of dancing on radial or lumbar bone density could be observed. Linear regression analysis showed that the lower the qCT at the beginning of the observation period, the higher was the percentage increase of spinal qCT in the entire group during 12 mo of dancing (r = 0.52, P < 0.0001). For additional evaluation, females were divided into two subgroups, osteoporotic or nonosteoporotic, based on x-rays and lumbar bone mineral density (BMD) as measured by qCT. The group classified as dancers with osteoporosis (group I) showed a significant increase in lumbar bone density, whereas in the group of dancers without signs of osteoporosis (group II), BMD remained unchanged. Additionally, radial bone density did not show any changes in either group. Group I showed a significant correlation between basal spinal BMD and the percentage change of BMD during the observation period (r = 0.7, P < 0.001). Changes of the biochemical parameters were observed in the bone-specific isoenzyme of alkaline phosphatase, a marker of osteoblastic activity, in group I giving additional evidence of increased bone formation.

Absorptiometry, Photon↗

PubMedDate not supplied

Myofibrillar (desmin-related) myopathy: clinico-pathological spectrum in 3 cases and review of the literature.

Myofibrillar or desmin-related myopathies encompass neuromuscular disorders with abnormal deposits of desmin and myofibrillar alterations. We report 3 unrelated patients presenting with proximal and distal myopathy, and, as a unique congenital syndrome, diffusely distributed myopathy, osteoporosis and myopia. Muscle biopsies shared cytoplasmic inclusions, rimmed vacuoles, and ragged-red-like fibers. Sarcoplasmic inclusions, either plaque-like or amorphous, strongly immunoreacted on dystrophin and variably for desmin, alphaB crystallin and ubiquitin. Cyclin-dependent kinases CDK1, CDK2 and CDK5 were overexpressed in affected fibers. Ultrastructurally, focal myofibrillar disruption was accompanied by tubulo-filamentous inclusions in one case and abundant glycogen and enlarged mitochondria displaying respiratory chain dysfunction at biochemistry in another case. Molecular analysis of the alphaB crystallin gene coding sequence and exons 4, 5 and 6 of the desmin gene did not reveal any mutation. The morphologic denominator of hyaline structures and areas of myofibrillar destruction occurs in heterogeneous conditions and may overlap with features of inclusion body myopathy and mitochondrial myopathy.

Adult↗

PubMedDate not supplied

[Perspectives on therapy with diphosphonates in non-malignant diseases].

Diphosphonates inhibit bone resorption. This therapeutic effect found early recognition in the treatment of Paget's disease. The favorable long-term effect of the substance gives rise to a shorter therapy period. Due to increased fracture incidence as a result of osteoidosis observed under ethane-hydroxy diphosphomate (EHDP) administration, today amino-hydroxy-propylidine diphosphonate (APD) and dichloromethylene diphosphonate (clodronate) are preferred in the treatment of Paget's disease. Diphosphonates inhibit both osteoblasts and osteoclasts, thus being also used in the treatment of primary osteoporosis. Their efficacy in high-turnover osteoporosis in the form of monotherapy or within the framework of cyclical therapy schemes has been demonstrated by an increase in bone mass. Diphosphonates have played an important role in the therapy of steroid-induced osteoporosis. Prevention of osteopenic changes is of utmost significance: a prophylactic effect was demonstrated in immobilization osteoporosis. In prophylaxis, diphosphonates might also be applied in women after ovariectomy who had to undergo surgery before the menopause due to oncologic indications and in whom the administration of estrogens to prevent expected osteoporosis is contra-indicated. The favorable effect of diphosphonates on bone changes in Gaucher's disease implies an inhibition of macrophage-mediated bone resorption. The importance of this substance in orthopedics will further contribute to prevent ectopic ossification in hip endoprosthetics.

Aged↗

PubMedDate not supplied

[Recent possibilities for the treatment of osteoporosis in the aged].

Treatment of idiopathic osteoporosis in the elderly presupposes exact radiological diagnosis, the exclusion of a primary illness as the cause of the pathological process and exact differential diagnosis from other metabolic osteopathies. We consider possible means of prevention of the immobilization of old people, and appropriate hormonal substitution in cases of previous illnesses which coincide with a disturbance of the gonadal function, as important prophylactic measures. In the case of manifest osteoporosis, if possible, an assignment of the disease to a manifestation with high or low bone turnover should be made, by means of biochemical adjuvants. In high bone turnover, the substitution of sex hormones or the administration of calcitonin is indicated, particularly if symptoms of pain are distinct. In osteoporosis with low bone turnover, fluoride in long-term therapy is the preferred medication. The latest studies show that a combination of fluoride and active vitamin D metabolites is preferable to monotherapy. All therapy for this disease, independent of the age of the patient, should be supported by isometric exercises, analgesics and appropriate dietary measures. Orthopaedic supporting measures should be applied only if conservative measures in acute vertebral fractures fail.

Aged↗