Strength and Stability Analysis of Rehabilitated Anterior Cruciate Ligament Individuals

Abstract

The anterior cruciate ligament (ACL) serves as a vital stabilizer for the human knee, yet it is one of the most injured ligaments in the body. Function of the knee is restored through reconstruction and physical therapy, but long term functional deficits persist in some individuals. To better understand the influence of post rehabilitation outcomes on dynamic balance performance, this study evaluated bilateral differences in strength and stability in 11 participants who have rehabilitated from an ACL reconstruction or repair. The Y-Balance Test and an isokinetic strength assessment using the Biodex dynamometer were used to measure dynamic knee stability and strength, respectively. No significant differences were found in the strength test measurements. However, side to side differences in Y-Balance Test composite score (-2.8±3.1%, p = 0.014), maximal anterior reach (-2.8±2.4 cm, p = 0.01), and posterolateral reach (-2.75±3.5 cm, p = 0.02) were found to be significantly impaired in participants' involved limbs compared to the uninvolved limbs.

Keywords: ACL reconstruction; average power; dynamic stability; peak torque; work.

Figure 1

Mean and standard deviation for composite scores during Y-Balance Test for the involved and uninvolved limb. *Involved limb significantly different from uninvolved limb, p < 0.05.

Figure 2

Mean and standard deviations for maximal reach distances in anterior (ANT), posterolateral (PL), and posteromedial (PM) directions during Y-Balance Test for the involved (IN) and uninvolved (UN) limb. *Involved limb significantly different from uninvolved limb, p < 0.05.