Search PubMed⌕ Search

Biomedical subjects

A Sarmiento

Publications and source records attributed to A Sarmiento.

At least 109 records · Page 6Linked to original sources
PubMed1982

Prosthetic hip range of motion and impingement. The effects of head and neck geometry.

Two major design parameters to total hip arthroplasty which can be selected to optimize for anatomical variation are head diameter and neck length. By using a cadaveric pelvis mounted in a three-dimensional protractor, it was shown that increased head-neck diameter ratio results in increased range of motion, with decreased prosthetic impingement, and that increased neck-length results in increased range of motion, with increased prosthetic impingement. Head diameter has no range of motion effect in arcs characterized exclusively by bony impingement, and neck length has no range of motion effect in arcs characterized exclusively by prosthetic impingement. The surgeon is currently confronted with a variety of prostheses with different head-neck diameter ratios and neck lengths. When choosing the optimal prosthesis for a particular patient, the surgeon is often restricted by various anatomical constraints. While a large head diameter cannot always be chosen, an adequate range of motion without prosthetic impingement can still be achieved by ensuring that head-neck diameter ratio is optimum. A sufficient neck length to ensure adequate range of motion is desirable, but the neck should not be so long that neck-socket impingement is of concern. Optimum clinical range of motion, with minimal prosthetic impingement, may be achieved with a large head size and a medium neck length.

Biomechanical Phenomena↗
PubMed1980

A quantitative comparative analysis of fracture healing under the influence of compression plating vs. closed weight-bearing treatment.

The study compared the healing of fractures treated with rigid immobilization with the healing of fractures without internal fixation. Comparative studies were made of the cytologic, morphologic and mechanical properties of callus from closed fractures in 2 groups of dogs: one plated, the other not. Significant differences were observed in the 2 groups in early stages of healing. The biomechanical differences between the 2 groups persisted into later stages of healing, even after histologic and electron microscopic appearance of cellular activity and new bone formation had become similar. In general, closed, nondisplaced fractures of dogs' radii treated without surgical procedures and followed by early functional activity demonstrated a cytologically more active endosteal callus and increased biomechanical strength characteristics at the fracture site.

Animals↗
PubMed1979

Clinical experiences with a titanium alloy total hip prosthesis: a posterior approach.

Using a titanium alloy femoral prosthesis (STH Zimmer) and an ultra high molecular weight polyethylene acetabular cup with a posterior surgical approach to the hip joint, 237 consecutive total hip arthroplasties in 215 patients were performed between December 1975 and May 1977. The preliminary results and early postoperative complications suggest that this system can be considered an alternative to total hip arthroplasty using other materials and surgical approaches.

Adult↗
PubMed1978

Functional fracture-bracing of long-bone fractures of the lower extremity in children.

Fifty-six tibial fractures in fifty-five children, sixteen years old or younger, and seventeen femoral fractures in seventeen children in the same age group, seven of them with associated tibial fractures, were treated by fracture-bracing. The tibial fractures healed in an average of 13.2 weeks with no complications that could be attributed to failure of the method. The femoral fractures healed in an average of seventeen weeks. There was an angular femoral deformity of more than 5 degrees in seven of seventeen patients, all but one in fractures of the middle third of the femoral shaft. Of nine distal fractures, only one had angulation of more than 5 degrees. Therefore, the method should be restricted to fractures in the distal third of the femoral shaft. Fracture-bracing gave more freedom to the child and was eminently satisfactory to the parents.

Adolescent↗
PubMed1977

Fracture healing in rat femora as affected by functional weight-bearing.

Femoral fractures were created in rats to determine whether there were differences in healing under conditions of immobilization and under conditions of immediate weight-bearing. Histological and roentgenographic differences were present by the second week after fracture and differences in mechanical properties were also present. These differences became progressively greater during the next three weeks. Functional weight-bearing was found to accelerate the rate of fracture healing and to improve significantly the strength of the healing bone.

Animals↗
PubMed1977

Functional bracing of fractures of the shaft of the humerus.

We treated fifty-one cases of fracture of the shaft of the humerus with a functional method of treatment consisting of a plastic sleeve, individually molded or prefabricated. It maintained good alignment of the fragments and permitted rapid and uninterrupted osteogenesis. The early introduction of functional activity to the entire extremity appears to provide a desirable physiological environment conducive to rapid healing. Non-unions have not been encountered in nonpathological fractures. Healing time has been rapid, and there has been consistent restoration of motion of all joints prior to the completion of healing. The morbidity was minimum.

Adolescent↗
PubMed1976

Treatment of ulnar fractures by functional bracing.

Treatment of isolated fracture of the ulna by means of functional bracing was successful in seventy-two cases. No non-unions were encountered. There was minimum deformity and loss of pronation-supination, and no loss of motion at the elbow and wrist. The average time to healing was ten weeks.

Adolescent↗
PubMed1976

A clinical evaluation of aspirin prophylaxis of thromboembolic disease after total hip arthroplasty.

Prophylaxis of thromboembolic disease using aspirin was studied prospectively in 340 patients undergoing total hip replacement, excluding those with prior thromboembolic disease. Clinical criteria were used to diagnose thrombophlebitis, while clinical criteria, roentgenography, blood-gas determinations, electrocardiography, and pulmonary vascular scanning were used to diagnose pulmonary emboli. Five patients had signs of symptoms of pulmonary emboli, all confirmed by pulmonary vascular scan. No fatal pulmonary emboli occurred. Twenty-six patients had thrombophlebitis. Without simultaneous control group, a reduction in postoperative thromboembolic disease in these patients receiving aspirin was not proved. However, the observed low incidence of clinically evident thromboembolic manifestations suggests that aspirin may be a simple and useful prophylactic agent in these patients.

Adolescent↗
PubMed1975

Forearm fractures. Early functional bracing - A preliminary report.

Forty-five fractures of the forearm in forty-three patients were treated with a functional below-the-elbow brace applied three to forty-two days after injury, at a median time of fifteen days. The brace permitted flexion and extension of the wrist and elbow while limiting pronation and supination of the forearm during the fracture's reparative period. The results were rewarding, with only one non-union and minimum impairment of function in the overwhelming majority of cases.

Braces↗
PubMed1975

Colles' fractures. Functional bracing in supination.

The classic position of immobilization of Colles' fractures with the elbow in flexion, the forearm in pronation, and the wrist in volar flexion and ulnar deviation is probably the main reason for the common and rapid recurrence of the original deformity. Such a position places the brachioradialis muscle, a strong flexor of the elbow and the only muscle attached to the distal fracture fragment, in an ideal physiological position to exert a deforming force on the fracture fragments. Based on this assumption, further supported by electromyographic studies, a method of treatment was developed which calls for the initial immobilization of the arm in an above-the-elbow cast with the elbow in flexion, the forearm in supination, and the wrist inmoderate ulnar and volar flexion. This cast is changed a few days after application for an Orthoplast brace that permits motion of the elbow and volar flexion of the wrist while preventing pronation and supination of the forearm and dorsiflexion of the wrist. The proposed method did not prevent collapse of the fragments in all instances. However, the degree of collapse was minimum. The position of supination of the forearm and the freedom of motion of all joints seemed to reduce the swelling, stiffness, and incapacitation frequently found during active treatment of these fractures.

Braces↗