Context: Abnormal movement patterns have been implicated in lower extremity injury. Reliable, valid, and easily implemented assessment methods are needed to examine existing musculoskeletal disorders and investigate predictive factors for lower extremity injury. Objective: To determine the reliability of experienced and novice testers in making visual assessments of lower extremity movement patterns and to characterize the construct validity of the visual assessments. Design: Cross-sectional study. Setting: University athletic department and research laboratory. Patients or Other Participants: Convenience sample of 30 undergraduate and graduate students who regularly participate in athletics (age = 19.3 ± 4.5 years). Testers were 2 experienced physical therapists and 1 novice postdoctoral fellow (nonclinician). Main Outcome Measure(s): We took videos of 30 athletes performing the single-legged squat. Three testers observed the videos on 2 occasions and classified the lower extremity movement as dynamic valgus, no change, or dynamic varus. The classification was based on the estimated change in frontal-plane projection angle (FPPA) of the knee from single-legged stance to maximum single-legged squat depth. The actual FPPA change was measured quantitatively. We used percentage agreement and weighted κ to examine tester reliability and to determine construct validity of the visual assessment. Results: The κ values for intratester and intertester reliability ranged from 0.75 to 0.90, indicating substantial to excellent reliability. Percentage agreement between the visual assessment and the quantitative FPPA change category was 90%, with a κ value of 0.85. Conclusions: Visual assessments were made reliably by experienced and novice testers. Additionally, movement-pattern categories based on visual assessments were in excellent agreement with objective methods to measure FPPA change. Therefore, visual assessments can be used in the clinic to assess movement patterns associated with musculoskeletal disorders and in large epidemiologic studies to assess the association between lower extremity movement patterns and musculoskeletal injury.

Study Design: Controlled laboratory study. Objectives: To compare hip and knee kinematics and pain during a single-limb squat between 3 movement conditions (usual, exaggerated dynamic knee valgus, corrected dynamic knee valgus) in women with patellofemoral pain. Background: Altered kinematics (increased hip adduction, hip medial rotation, knee abduction, and knee lateral rotation, collectively termed dynamic knee valgus) have been proposed to contribute to patellofemoral pain; however, cross-sectional study designs prevent interpreting a causal link between kinematics and pain. Methods: The study sample included 20 women with patellofemoral pain, who demonstrated observable dynamic knee valgus. Participants performed single-limb squats under usual, exaggerated, and corrected movement conditions. Pain during each condition was assessed using a 0-to-100-mm visual analog scale. Hip and knee frontal and transverse plane angles at peak knee flexion and pain levels were compared using repeated-measures 1-way analyses of variance. Pearson correlation coefficients were used to determine within-condition associations between kinematic variables and pain. Results: In the exaggerated compared to the usual condition, increases were detected in hip medial rotation (mean ± SD difference, 5.8° ± 3.2°; P<.001), knee lateral rotation (5.5° ± 4.9°, P<.001), and pain (8.5 ± 10.8 mm, P = .007). In the corrected compared to the usual condition, decreases were detected in hip adduction (mean ± SD difference, 3.5° ± 3.7°; P = .001) and knee lateral rotation (1.6° ± 2.8°, P = .06); however, average pain was not decreased (1.2 ± 14.8 mm, P = 1.0). Pain was correlated with knee lateral rotation in the usual (r = –0.47, P = .04) and exaggerated (r = –0.49, P = .03) conditions. In the corrected condition, pain was correlated with hip medial rotation (r = 0.44, P = .05) and knee adduction (r = 0.52, P = .02). Conclusion: Avoiding dynamic knee valgus may be an important component of rehabilitation programs in women with patellofemoral pain, as this movement pattern is associated with increased pain. J Orthop Sports Phys Ther 2012;42(12):1017–1024, Epub 5 September 2012. doi:10.2519/jospt.2012.4231