Muscle strength in individuals with healed burns.

OBJECTIVE

To quantify the long-term effects of burns on muscle strength and to investigate the impact of the initial severity of the trauma on muscle strength.

DESIGN

Cross-sectional study comparing individuals with healed burns to nonburned control individuals matched for age, gender, body mass index, and physical activity level.

SETTING

Subjects were selected from the data bank of a burn center of a large Montreal teaching hospital and tested in a university laboratory.

PATIENTS: Thirty subjects (mean age, 36.3 +/- 11.5 yrs) with second- and third-degree burns covering 15% to 75% of total body surface area (TBSA) (mean, 35.5% +/- 15.9%) were evaluated more than 1 year after discharge (mean, 37.3 +/- 20.4 months; range, 15 to 92 months). Thirty unburned subjects were recruited from the community at large.

MAIN OUTCOME MEASURE: Maximal torque, work, and power developed by the elbow and knee flexors and extensors.

RESULTS

Subjects with burns of > 30% of TBSA produced significantly less torque, work, and power in the quadriceps than control subjects (15.2% to 20.5% depending on velocity [p < .05]). The ability to develop muscle power at the elbow was also compromised in the severely burned subjects (19.2% in extension and 18.7% in flexion [p = .07]) at the faster velocities. No differences were observed between controls and patients with small burn injuries (TBSA of < 30%).

CONCLUSION

Patients who had severe burns (TBSA of > 30%) had weaker muscles even years after the trauma, suggesting either an inability to fully recover or insufficient rehabilitation.