PURPOSE

This study was carried out to investigate the effect of selective strengthening  of the vastus medialis oblique muscle (by electrical stimulation and quadsetting) on the muscle bulk and quadriceps angle (Q-angle).

RELEVANCE

The outcome of this study showed that selective strengthening of the vastus medialis oblique muscle through electrical stimulation or quadsetting significantly increased the muscle bulk and the Q-angle. This will be useful in addressing problems secondary to quadriceps muscle atrophy especially the medial component.

PARTICIPANTS

Forty apparently healthy male subjects aged between 19 and 25 years participated in the study. They were volunteers from the student population of the College of Medicine, University of Ibadan, Nigeria.

METHODS

Participants who had no history of patellofemoral joint disorders and tested negative to the patella apprehension test were randomly assigned to two groups. Group I had their VMO trained by electrical stimulation while Group II had their VMO trained by quadsetting. The right limbs were trained and the left limbs served as control. Muscle bulk and Q-angle were measured in both limbs pre and post-training.

ANALYSIS

Data were summarized using the descriptive statistics of mean and standard deviation. The independent t-test was used to compare between the two groups while the paired t-test was used to compare pre and post-training values as well as contralateral limbs in each group. The α-level was set at 0.05.

RESULTS

In the group I (electrical stimulation) subjects, the mean change in right and left muscle bulk were 1.86±0.69cm and 0.35±0.22cm respectively and the mean change in right and left Q-angles were 0.95±0.82^o and 0.15±0.75^o respectively. In the group II (quadsetting) subjects the mean change in right and left muscle bulk were 2.30±0.87cm and 0.45±0.24cm respectively and the mean change in right and left Q-angles were 1.15±0.81^o and 0.25±0.55^o respectively. The paired t-test showed significant differences (p<0.05) between the changes in VMO muscle bulk and Q-angle in the trained versus untrained limbs in the two groups. However, the independent t-test showed that the across-group differences were not significant (p>0.05).

CONCLUSION

Selective strength training of the VMO muscle using either electrical stimulation or quadsetting increase the muscle bulk and Q-angle. Both electrical stimulation and quadsetting are suitable for training the VMO muscle and neither method is superior to the other.

IMPLICATIONS

Selective strength training of the VMO muscle using either electrical stimulation or quadsetting may be useful in managing patellofemoral joint pathologies that are related to muscular atrophy of the quadriceps femoris especially the VMO.

KEYWORDS

Q-angle, Vastus medialis oblique muscle, Quadsetting, Electrical stimulation