Biofeedback supplementation to physiotherapy exercise programme for rehabilitation of patellofemoral pain syndrome: a randomized controlled pilot study

Objectives: To examine the efficacy of electromyographic (EMG) biofeedback supplementation to exercise rehabilitation for people with patellofemoral pain syndrome.

Design: Double-blinded randomized clinical controlled pilot trial.

Setting: Clinical setting with home programme.

Participants: Twenty-six subjects diagnosed with patellofemoral pain.

Intervention: Subjects were randomly assigned into EMG biofeedback+exercise group or exercise-only group. All subjects participated in an eight-week home exercise programme, while the biofeedback group also received EMG visual feedback of their quadriceps muscle activities during the exercises.

Main outcome measures: Isokinetic knee extension strength, patellar alignments and perceived pain severity were assessed in weeks 0, 4 and 8 for all subjects. The data within and between groups were compared by repeated measures ANOVA with aα=0.05.

Results: Both groups improved in isokinetic peak torque (P=0.005), work output (P=0.037) and patellar alignments (P=0.001-0.014). Besides, there was a trend of decrease in pain (P=0.088). The biofeedback group improved faster than the exercise group in lateral patellar rotation and peak torque per body weight, although no statistically significant difference was shown.

Conclusion: Biofeedback supplement to the exercise programme might hasten the improvement for subjects with patellofemoral pain in the first few weeks of a physiotherapy exercise programme, but this needs further study before being used.

Acute effects of kinesio taping on knee extensor peak torque and electromyographic activity after exhaustive isometric knee extension in healthy young adults

OBJECTIVE

To evaluate the effect of Kinesio Tex tape and its method of application, Kinesio Taping (KT) on knee extensor performance before and after an exhaustive isometric knee extension exercise.

DESIGN

Single-blinded, randomized control trial.

SETTING

Centre for Sports Training and Rehabilitation at The Hong Kong Polytechnic University.

PARTICIPANTS

Twenty-six healthy volunteers with no history of knee injuries.

INTERVENTIONS

Subjects were randomized to either the KT or sham taping group.

MAIN OUTCOME MEASURES

The effects of KT on the neuromuscular performance of the knee extensors were measured before and after KT application, and immediately and 5 and 10 minutes after an exhaustive isometric knee extension exercise.

RESULTS

Within-group analyses revealed a significant effect of time on the peak torque in isometric knee extension (F2.73,65.44 = 24.5, P < 0.001), but no significant group (F2.73,65.44 = 2.13, P = 0.11) or interaction (F1,24 = 0.59, P = 0.45) effect. A significant time effect (F2.52,60.14 = 3.75, P = 0.02) and a significant time × group interaction (F1,24 = 4.59, P = 0.04) was found for the rate of peak torque development. Post hoc comparisons revealed significantly higher rates in the intervention group (F1,24 = 4.594, P = 0.04) over all 5 tests. No significant effects of time (F4,96 = 0.88, P = 0.48; F2.56,61.35 = 2.75, P = 0.06), group (F4,96 = 0.56, P = 0.69; F2.56,61.35 = 1.16, P = 0.33), or time × group interaction (F1,24 = 2.77, P = 0.11; F1,24 = 0.20, P = 0.66) were found for either the electromechanical delay or electromyographic results, respectively.

CONCLUSIONS

The present study suggests that KT shortens the time required to generate peak torque during isometric knee extension, which has important implications for sports performances that require the rapid generation of peak muscular force.

CLINICAL RELEVANCE

Kinesio taping is commonly seen in the sports arena. The popularity is presumably due to the general belief in its injury prevention and enhancement of muscle performance. The results of the present findings suggested that KT shortens the time to reach peak torque generation. Aside from this, there is no other significant positive effect on muscle performance. Further investigation on the effects of KT on muscle performance is warranted.

Motion control shoe delays fatigue of shank muscles in runners with overpronating feet

BACKGROUND

The motion control shoe is a well-developed technology in running shoe design for controlling excessive rearfoot pronation and plantar force distribution. However, there is little information on the leg muscle activation with different shoe conditions.

HYPOTHESIS

The motion control shoe can prevent excessive shank muscle activation and delay fatigue.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twenty female recreational runners with excessive rearfoot pronation were tested with running 10 km on a treadmill on 2 days. Participants wore either a motion control running shoe or neutral running shoe on each day. Activities of their right tibialis anterior and peroneus longus were recorded with surface electromyography. The normalized root-mean-square electromyography and median frequency were compared between the 2 shoe conditions.

RESULTS

Significant positive correlations were found between the root-mean-square eletromyography and running mileage in both the tibialis anterior and peroneus longus in the neutral shoe condition (P <.001). The median frequency dropped in both shoe conditions with mileage, but paired t tests revealed a significantly larger drop in the neutral shoe (P < .001 for peroneus longus, P = .074 for tibialis anterior).

CONCLUSION

The motion control shoe may facilitate a more stable activation pattern and higher fatigue resistance of the tibialis anterior and peroneus longus in individuals with excessive rearfoot pronation during running.

CLINICAL RELEVANCE

The motion control shoe may increase the running endurance, thus reduce overuse injuries, in athletes with unstable feet during long-distance running.

Patellar taping affects vastus medialis obliquus activation in subjects with patellofemoral pain before and after quadriceps muscle fatigue

Objective: To investigate the effects of patellar taping on the electromyographic onset of vastus medialis obliquus and vastus lateralis, and their magnitudes of reflex contraction before and after quadriceps muscle fatigue in subjects with patellofemoral pain.

Methods: Sixteen adults (5 males) diagnosed with patellofemoral pain were studied. The timing of surface electromyography onset and magnitude of vastus medialis obliquus and vastus lateralis contractions were measured during a postero-anterior knee perturbation test. The tests were conducted in random order under three conditions of real taping, placebo taping and no taping. Afterwards, the subjects performed knee extension exercises until fatigue and the above tests were repeated, so as to examine the effects of patellar taping in a muscle fatigued condition.

Results: There was no significant difference in electromyographic onset timing of vastus medialis obliquus and vastus lateralis or in the amplitude of vastus lateralis contraction among the different testing conditions. For vastus medialis obliquus amplitude, however, it was significantly higher in the no taping than the real taping condition regardless of the state of fatigue (P = 0.013).

Conclusions: The present study suggests that patellar taping might not enhance the temporal activation of vastus medialis obliquus in subjects with patellofemoral pain before and after muscle fatigue. Furthermore, vastus medialis obliquus contraction might be inhibited by patellar taping.

Patellar Taping Does Not Affect the Onset of Activities of Vastus Medialis Obliquus and Vastus Lateralis Before and After Muscle Fatigue

OBJECTIVE

This study examined the immediate effect of patellar taping with a standard force on the onset of vastus medialis obliquus and vastus lateralis activities before and after muscle fatigue in able-bodied subjects.

DESIGN

This study tested 29 mature able-bodied subjects. The surface electromyographic onset time of their vastus medialis obliquus and vastus lateralis was measured after a posteroanterior perturbation at the knee in a single-legged standing position. The measurements were taken under three conditions in random order of true patellar taping, sham patellar taping, and no patellar taping. Afterward, subjects performed a knee-extension exercise until their quadriceps fatigued, and the above tests were repeated to test the effect of fatigue on the outcome.

RESULTS

There was no statistically significant difference with patellar taping on the electromyographic onset time of the vastus medialis obliquus and vastus lateralis compared with the placebo-taping and no-taping conditions (P = 0.455). There was no statistically significant difference in onset of vastus medialis obliquus and vastus lateralis muscles before and after muscle fatigue (P = 0.304).

CONCLUSIONS

The present study suggests that patellar taping does not enhance the temporal activation of vastus medialis obliquus in both fatigue and nonfatigue conditions on able-bodied subjects.