The effects of electrical stimulation on the control of muscle atrophy and strength in meniscectomy patients
Creators: name: Baker, Robert James
Publisher: name: University of British Columbia
Year: 2010

description: After knee surgery, the development of leg strength and size to its original levels are important requirements in the recovery. The major aim in the rehabilitation of a meniscectomy is to return the injured limb to its original size by a program of active exercises. Failure to do this may result in limited activity and re-injury to the knee joint A program of electrical stimulation has been found to be effective in controlling muscle atrophy during the time of denervation in animals and humans (in animals - Schimrizk et a 1976; Herbison et al, 1973, 1971; Stillwell et al, 1962 and Guttman and Guttman, 1942; in humans - Osbourne, 1951 and Jackson and Seddon, 1945). At the present time no studies have been done to determine if electrical stimulation will be effective in controlling muscle atrophy in normally innervated muscles during the period of immobilization. The purpose of this investigation was to determine the effects of a 10-12 day program of electrical stimulation on the control of muscle atrophy and strength loss during the period of immobilization. A subproblem of this investigation was to determine the relationship between muscle atrophy and strength loss. The subjects for this study were eighteen patients undergoing a meniscectomy operation (mean age 22.7 yrs.). Subjects were rated according to strength per body weight and assigned to a control or an experimental group. The experimental group participated in a five session program of electrical stimulation in addition to a standard physiotherapy program. The control group participated only in the standard physiotherapy program. The electrical stimulation consisted of five sessions each lasting ten minutes. Ninety muscle contractions were made during the ten minute session. The sessions were held on weekdays within a 10-12 day period of the operation. The first session was held 48 hours after the operation. In the first two sessions the leg was stimulated at the immobilized angle and in the remaining three sessions the leg was stimulated at 115 degrees of extention. All subjects were tested one day prior to the operation and at the end of the 10-12 day period for thigh volume and maximal isometric leg strength. The following hypotheses were tested for significance at the .05 level. 1. The use of electrical stimulation in addition to the standard physiotherapy program will show less muscle atrophy as compared to the standard physiotherapy program. 2. The use of electrical stimulation in addition to the standard physiotherapy program will maintain a higher level of original isometric strength as compared to the standard physiotherapy program. 3. There is a positive linear relationship between muscle atrophy and strength loss. Analysis of variance revealed that hypothesis #1 is supported at the .01 level and hypothesis #2 is not supported at the .05 level of significance. The Pearson Product Moment Correlation showed that hypothesis #3 is supported when the two groups were combined and for the control group only at the .01 level of significance, but not for the treatment group only, at the .05 level.