The Functional Movement Screen (FMS) Deep Squat (DS) utilizes set biomechanical criteria to determine successful completion of a fundamental movement pattern. It is suggested that dysfunction exhibited during FMS tests may predispose individuals to musculoskeletal injury. Successful completion of the DS requires a subject to meet the following four criteria: 1. The torso is parallel to the tibia or toward vertical, 2. The femur is below horizontal, 3. The knees do not track inside of the feet, and 4. The dowel is aligned over the feet. The complexity of the DS makes accurate identification of dysfunctional patterns difficult.
PURPOSE: To investigate the frequency of DS dysfunction criteria both individually and in combination, and to determine the percent agreement in the identification of DS dysfunction patterns.
METHODS: Forty-one physically active individuals (21F, 20 M; 20.8 ± 1.4 yo; 68.5 ± 13.4 kg; 1.7 ± 0.17 m) performed the DS. One subject was removed due to incomplete data. All subjects completed an informed consent and injury history questionnaire for this IRB approved study. Participants performed 3 DS trials according to standard FMS protocols and were recorded using Microsoft LifeCam webcams in the frontal and sagittal planes. Two raters viewed video of all trials and each subject’s best trial was retained and categorized by demonstrated dysfunction(s).
RESULTS: Percent agreement was calculated between the raters (Percent Agreement = 60%). Thirty-three subjects presented with movement dysfunction with 29 demonstrating 2 or more dysfunctions and only 4 subjects demonstrating a singular dysfunction. The most frequently observed combination of dysfunctions was the torso falling beyond parallel to the tibia, the femur not reaching the horizontal, and the dowel tracking beyond the foot, which was observed in 15 subjects. Six subjects demonstrated all 4 movement dysfunctions.
CONCLUSION: The DS is a complex movement pattern and individuals that demonstrate dysfunction often present with multiple dysfunctions. As a result, agreement between raters is lacking. Misidentification of dysfunction(s) results in a missed opportunity for clinicians to correct potentially harmful dysfunctional movement patterns.