Date of Award

1995

Document Type

Scholarly Project

Degree Name

Master of Physical Therapy (MPT)

Department

Physical Therapy

First Advisor

Thomas Mohr

Keywords

Exercise Test -- methods; Kinetics; Walking

Abstract

Many physical therapy diagnoses require minimal anterior loading of the knee in their rehabilitation protocols. These include, but are not limited to, tibial plateau fractures, patellofemoral pain, patellar fractures, quadriceps tendinitis, and status post anterior cruciate ligament reconstruction. In the clinical setting, backward walking (BW), or "retro-walking," is often used during the rehabilitation of such diagnoses. We propose backward walking will initiate greater hamstring recruitment due to the kinematics and kinetics of this gait pattern and thereby result in less anterior knee stress. It is the purpose of this research project to determine if hamstring recruitment can increase in a closed kinetic chain (CKC).

Motor points from the quadriceps (00), medial hamstrings (MH), lateral hamstrings (LH), and lateral gastrocnemius (LG) were found on the right lower extremity. In addition, footswitch electrodes were placed over the heel, the ball of the great toe, the fifth metatarsal head, and the third metatarsal head. Data were collected from two trials of each forward walking (FW) and BW on a treadmill at two miles per hour.

The percent of maximal voluntary contraction (O/OMVC) was greatest in the LG, and followed in decreasing order by the VMO, MH, and LH, respectively. This trend held true for both gait cycles. However, the difference in %MVC was significantly greater ( α = .05) for the QD, MH, and LH during BW stance compared to forward stance. The LG had less EMG activity, but was not statistically significant. Increases in the electrical activity of the VMO was greater than that of either the MH or LH. Thus, although hamstring recruitment did increase, it was not to the same degree as the VMO. Because of this, backward walking may be best suited for patients who require hamstring strengthening, but particularly quadriceps strengthening.

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