Search PubMed⌕ Search

Biomedical subjects

L L Latta

Publications and source records attributed to L L Latta.

31 records · Page 2Linked to original sources
PubMed1987

Treatment of isolated ulnar shaft fractures with prefabricated functional fracture braces.

In a prospective study, from September 1980 to December 1984, 146 isolated ulnar shaft fractures were treated with prefabricated fracture braces. Clinical and roentgenographic follow-up data were available for 73 fractures. Functional results were rated excellent in 64 fractures (88%), good in seven (9%), and poor in two (3%). All fractures healed in an average time of 57 days. The mean angulation measured 6 degrees in the mediolateral plane and 4 degrees in the anteroposterior plane. The complication rate was 18%, relating mostly to residual angulation. Most isolated fractures of the distal one-half of the ulnar shaft can be treated successfully with prefabricated fracture braces.

Adult↗
PubMed1987

Conservative management of difficult phalangeal fractures.

Stable fractures of the metacarpal and proximal phalanges can be treated satisfactorily by closed methods. The problem in those unstable fractures is whether to treat with open or closed reduction. Stiffness of the proximal interphalangeal joint (PIP), malunion, rotation deformities, shortening, and nonunion are known complications of fractures of the proximal phalanx. Fractures at the base of the proximal phalanx. Fractures at the base of the proximal phalanx have low incidence of complications if they are treated closed. Fractures at the shaft carry a much larger risk of complications with either type of treatment. This study of 158 fractures of the proximal phalanx demonstrates that there is a place for conservative treatment in the management of unstable shaft fractures of the proximal phalanx.

Casts, Surgical↗
PubMed1984

Healing of fractures with freeze-dried cortical bone plates. Comparison with compression plating.

The healing of fractures of the radius with internal fixation by stainless-steel compression plates was compared with fractures fixed with freeze-dried bone-plate allografts. Fractures fixed with metallic plates gained slightly less than half the biomechanical strength of the contralateral control bone and healed without noticeable external callus formation. Bone-plated fractures regained three-fourths of the biomechanical strength of controls and healed by forming an external callus. Bone-plate allografts were eventually incorporated in the host bone. Allograft plates were vascularized and remodeled into cancellous bone in the process of incorporation in the host bones.

Animals↗
PubMed1984

The effects of function in fracture healing and stability.

A mechanically based classification system and hypothesis for fracture healing with peripheral callus has been proposed based on many years of clinical experience and numerous laboratory research studies. This hypothesis describes the interactions and influences on fracture healing from the vascular, mechanical, electric, chemical, and thermal environments in specific callus regions surrounding the fracture site. The central theme to this phenomenon is motion at the fracture site. The single factor distinguishing the effects of closed functional bracing of fractures from all other treatment modalities is motion between the fragments which results from early functional activity. Perhaps the stimulus to a prolonged inflammatory response is provided by friction between moving fracture fragments and the surrounding tissues. An increased vascular response results, and environmental factors are stimulated to form an abundant peripheral callus. Three distinct callus zones exist which provide overlapping stages of healing based on structure and optimized physiologic conditions. Clinical signs and symptoms, such as fracture stability as well as motion and pain at the fracture site, combine to provide the optimum feedback mechanism to control functional activity, which in turn governs environmental factors. Roentgenographic appearance can be better judged for mechanical significance if these three callus regions are appreciated. In animals as well as in humans, if function has correctly influenced the environment during callus formation, refracture strength is often greater than that of the original bone.

Animals↗
PubMed1983

Histopathology and metallurgical analysis of a removed Lane plate at 53 years postimplantation: a case report.

A vanadium steel Lane plate with nickel coating and low grade steel screws were removed from a patient 53 years postimplantation. Corrosion of the parts was extreme, but the reaction in the surrounding tissues was surprisingly quiescent under the circumstances. By today's standards, the materials, their application, and their performance were totally unacceptable. However, the biological system tolerated this "insult" well.

Aged↗
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↗
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↗
PubMedDate not supplied

Biomechanics of a less invasive procedure for reconstruction of the ulnar collateral ligament of the elbow.

A reconstruction of the anterior bundle of the ulnar collateral ligament of the elbow using bone anchors was compared regarding strain and valgus load strength with the intact ulnar collateral ligament and the reconstructed ulnar collateral ligament using bone tunnels. In both normal and reconstructed elbows, the anterior band and posterior band were tight during only a portion of the range of motion. Toward extension, the mean peak strain in the anterior band was tight for the normal and bone anchor groups, but lax in the bone tunnel group. Toward extension, the mean peak strain in the posterior band was lax in all elbows. Toward flexion, the strain in the anterior band was lax in the normal and bone anchor groups, but tight in the bone tunnel group. The mean of the peak strains for the posterior band toward flexion was tight for all elbows. Mean valgus load strength of normal elbows was 22.7 +/- 9.0 N.m. The bone tunnel and bone anchor mean strengths were 76.3% and 63.5%, respectively, of normal elbow strength. We concluded that the bone anchor reproduced the normal anatomy and mechanical function of the ulnar collateral ligament more closely than the bone tunnel, and that both reconstruction methods were significantly weaker than the normal ulnar collateral ligament. However, we found no significant difference in reconstruction strength between bone anchor and bone tunnel.

Biomechanical Phenomena↗
PubMedDate not supplied

Abductor muscle performance in total hip arthroplasty with and without trochanteric osteotomy. Radiographic and mechanical analyses.

Total hip arthroplasty was performed for unilateral hip disease in 26 patients with trochanteric osteotomy (TS) and 27 patients without osteotomy (NS). Early postoperative recovery of function, pain, mobility, radiographic changes, and abduction torques were recorded and evaluated. Theoretic analysis of hip mechanics based on radiographic measurements was compared with measured abduction torques for each patient. Function, pain, and mobility ratings were similar for both groups pre- and postoperation. Radiographic measurements demonstrated better mechanical reconstruction of hips in both groups. There was a trend, but no statistically significant correlation, of mechanical parameters and measured isokinetic or isometric abduction torques at the hip joint in the TS group. In the NS group, no correlation was found between mechanical parameters and measured torques. A significant improvement in recovery of torque was found in the NS group when compared to the TS patients.

Aged↗
PubMedDate not supplied

Fracutres of the proximal tibia and tibial condyles: a clinical and laboratory comparative study.

Angulatory deformities frequently develop following condylar and proximal diaphyseal tibial fractures. Laboratory studies conducted in cadaver specimens with artificially created fractures closely resembled the behavior of fractures treated with functional braces. Providing that the fibula factor is properly assessed, selected condylar and proximal tibial shaft fractures can be successfully treated by nonsurgical means including early knee motion in a brace followed by graduated weight-bearing ambulation.

Adolescent↗
PubMedDate not supplied

Factors contributing to lysis of the femoral neck in total hip arthroplasty.

A radiographic analysis of 483 Charnley total hip arthroplasties performed from July 1970 to November 1975 demonstrated that 13% of the hips had lysis of the medial femoral neck. The findings suggest that the lysis of the medial femoral neck is significantly reduced if the femoral stem is oriented in a valgus or neutral position and with at least 5 mm of cement separating the stem of the prosthesis and the medial cortex of the femoral neck.

Bone Cements↗