Modified Quadriceps Strengthening Maneuver for Patients undergoing Acl Reconstruction-surface Electromyogrphic Analysis

Introduction: Quadriceps femoris muscle setting is isometric quadriceps femoris exercise which can be widely used in early knee rehabilitation.However this exercise cannot obtain enough co-contraction of the hamstrings. We succeeded in developing a simple training maneuver that is effective in obtaining co-contraction of the hamstrings-a modified maneuver for the quadriceps femoris (MQS) muscle setting.

Aim of Study: To analyze the effect of MQS muscle settings by Electromyographic (EMG) analysis.

Methodology: It is an experimental study including 50 normal healthy subjects (Age: 20-30, Sex: Male) from the K.K Sheth Physiotherapy College, Rajkot. Orthopaedic, Neurological, Cardiovascular and Un co-operative patients were not included in the study. The subjects underwent 2 Quadriceps settings. One was the normal quadriceps femoris muscle setting (NQS) and the other was MQS. Moreover, subjects had worn a sand bag of 2 or 5 kg on the ankle of the raised lower limb in MQS (MQS2, MQS5). EMG activity was recorded from surface electrodes on the vastus medialis, vastus lateralis, semitendinosus and biceps femoris.Statistical processing on four movements were conducted using repeated measures ANOVA. Significant differences were identified using the Fisher's least significant difference test.

Results: The activities of the hamstrings were greater in MQS than in NQS, and co-contraction of the quadriceps femoris and hamstrings was obtained in the MQS maneuver.

Discussion: In MQS, the hamstrings work with quadriceps femoris. The activities of rectus femoris declined as the load to the raised lower limb progressed from NQS to MQS5. While in NQS induce contraction of the quadriceps femoris alone. Conclusion: This study suggests that effective co-contraction of the hamstrings can be obtained in MQS.