Altered movement pattern after ACL injury : Review

Why this study relevant ?

A specific altered movement patterns are associated with deviations in muscular activity.If there is such association, it could have implications for future rehabilitation guidance where detection and improvement of altered movement patterns associated with deviations in muscular activation should be considered in ACL rehabilitation.

Summary :

The underlying mechanisms of altered movement patterns in individuals with ACL injury are not fully understood. The current study assessed single and double leg squat movement patterns using surface EMG on 6 muscles of the lower limb as well as video analysis.

How they performed study ?

Surface EMG was applied to the gluteus medius, vastus lateralis, biceps femoris, tibialis anterior, peroneus longus and gastrocnemius. A video camera captured movements from the front only.

The medial displacement of knee and lateral displacement of trunk was observed on the injured side during SIngle leg squat  which correlated by inefficient Glues medius activity.

SEMG was measured at 3 different time points –

  • at the start of the movement,
  • at transition from flexion to extension of the knee
  • at the end of the movement.

A total of 18 comparisons (6 muscles at 3 time points) between injured and non injured sides were made for each subject. SIngle leg squat showed 3 point statiscally significant differences and the DOuble leg squat  showed 9 point .

We concluded that altered movement patterns during functional assessments are not only caused by muscle weakness but probably also by altered senserimotor control.

Clinical implementation:

Proprioception training should be included in ACL injury patient . Only strengthening and stretching will not be helpful. From study don’t concentrate only on knee joint, proximal joint must be address.

What’s your thoughts on below questions?

Are double legged tasks an important part of rehab post ACL injury or should we be prescribing only single leg exercises to restore function?


Altered movement patterns and muscular activity during single and double leg squats in individuals with anterior cruciate ligament injury
Anna Trulsson, Michael Miller, […], and Martin Garwicz