Biomedical subjects

R B Heppenstall

Publications and source records attributed to R B Heppenstall.

At least 55 records · Page 3Linked to original sources

PubMed1983

Clinical and roentgenographic evaluation of nonunion of the forearm in relation to treatment with D.C. electrical stimulation.

A total of 50 nonunions of the forearm bones in 42 patients were reviewed. The mean age was 35.6 years, with the majority secondary to motor vehicle accidents. Five of the nine identified infections were due to primary closure of the initial open fracture. The middle third of the forearm was the most common site of the nonunion. The majority (96%) had significant displacement on the original roentgenograms. Open fractures were more apt to develop nonunions. A gap produced a significant therapeutic challenge and we conclude such are best managed with a bone graft. If a compression plate is applied in the presence of comminution, a bone graft is indicated. The overall success rate with 3 months of D.C. electrical stimulation in the absence of a gap or infection was 80.0%. This compares favorably with time-honored bone graft surgery for nonunion.

Adult↗

PubMed1983

Constant direct-current treatment for established nonunion of the tibia.

The treatment of nonunion of the tibia in 40 patients by constant direct current was evaluated in a prospective survey. The method was simple to apply and the complication rate was low, but considerable cooperation is required on the part of patients. The success rate was 85%. When two patients who had significant fracture gaps and the one patient who had an undetected synovial pseudarthrosis were excluded, the corrected, realistic success rate was 92.5%. The results are equal to or better than those obtained by bone grafting; the method eliminates the complications of open bone operations. Although the precise biophysical mechanisms actively involved in this nonunion therapy are not to date fully comprehended, it is clear that the technique has been safe and beneficial in the majority of cases.

Adult↗

PubMed1980

Evaluation and management of subtalar dislocations.

Twenty subtalar dislocations were reviewed in patients seen at the hospital complex of the University of Pennsylvania, 1950--1979. All patients were available for followup examination and roentgenographic review. These were 15 males and five females in the study. Length of followup ranged from 6 months to 23 years, mean, 4.2 years. Medial dislocation was most frequent, occurring in 17 out of 20. All three with lateral dislocations had associated fractures. All of the dislocations were closed injuries and only one patient required open reduction. Immobilization was maintained in a below-knee weight bearing cast for 6 weeks post-reudction. Of the patients, 80% demonstrated significant restriction of motion and 30% had roentgenographic evidence of arthritis. Few were symptomatic. Fourteen had excellent results, two good, two fair, and two poor. In general, a satisfactory result is to be expected with closed reduction following parenteral medication.

Adolescent↗

PubMed1979

Pathophysiologic effects distal to a tourniquet in the dog.

Intramuscular tissue pO2, pCO2, and pH were monitored distal to a pneumatic tourniquet in a dog hindleg preparation. A severe state of tissue hypoxia, hypercarbia, and acidosis was quantitated. The recovery time for tissue gases following release increased with increasing tourniquet time. Elevated c.p.k. and lactic acid values were noted at 2 hours of ischemia, reflecting the muscle changes at that time. Histologic sections revealed early signs of degeneration by 1 hour which progressively increased with increased tourniquet ischemia. On the basis of this study, we conclude that ischemia should not exceed 1 to 1 1/2 hours if significant pathophysiologic tissue changes are to be avoided. If longer time is required, intermittent release of the tourniquet for 10 minutes at the end of each hour of inflation will avoid complications.

Animals↗

PubMed1976

Fracture healing in the presence of chronic hypoxia.

Recent studies have demonstrated that fracture healing normally takes place under hypoxic conditions. The present study evaluated the effect of a state of chronic systemic hypoxia on fracture healing in dogs. A significant delay in fracture healing was demonstrated in the hypoxic animals roentgenographically, histologically, and by strength-testing criteria. A further reduction in the available oxygen supply below that present during normal repair had an adverse effect on fracture healing.

Animals↗

PubMed1975