STUDY DESIGN: Controlled laboratory study using a cross-sectional design. OBJECTIVES: To examine the kinematics and kinetics of the trunk and the physical characteristics of trunk and hip in golfers with and without a history of low back pain (LBP). BACKGROUND: Modified swing patterns and general exercises have been suggested for golfers with back pain. Yet we do not know what contributes to LBP in golfers. To create and validate a low back-specific exercise program to help prevent and improve back injuries in golfers, it may be valuable to understand the differences in biomechanical and physical characteristics of golfers with and without a history of LBP. METHODS: Sixteen male golfers with a history of LBP were matched by age and handicap with 16 male golfers without a history of LBP. All golfers underwent a biomechanical swing analysis, trunk and hip strength and flexibility assessment, spinal proprioception testing, and postural stability testing. RESULTS: The group with a history of LBP demonstrated significantly less trunk extension strength at 60°/s and left hip adduction strength, as well as limited trunk rotation angle toward the nonlead side. No significant differences were found in postural stability, trunk kinematics, and maximum spinal moments during the golf swing. CONCLUSION: Deficits observed in this study may affect a golfer’s ability to overcome the spinal loads generated during the golf swing over time. Exercises for improving these physical deficits can be considered, although the cause-effect of LBP in golfers still cannot be determined.

J Orthop Sports Phys Ther 2010;40(7):430-438, Epub 15 April 2010. doi:10.2519/jospt.2010.3152

KEY WORDS: balance, flexibility, golf swing, proprioception, strength

STUDY DESIGN: Controlled laboratory study. OBJECTIVES: To describe and compare scapular and clavicular kinematics and muscle activity during 6 retraction exercises in young healthy adults (mean ± SD age, 23.2 ± 2.4 years). BACKGROUND: Based on the association between shoulder injuries and scapular/clavicular movement, muscle activity during various exercises that target muscles surrounding the scapula have been investigated. However, the scapular and clavicular movements occurring during these exercises remain uninvestigated. Evaluation of the scapular and clavicular kinematics in addition to muscle activity provides additional information that allow clinicians to select exercises that best meet the patient’s needs. METHODS: Three-dimensional scapular and clavicular kinematics and scapular muscle activity data were collected while the participants performed 6 scapular retraction exercises. One-way repeated-measures ANOVA and post hoc analyses were used to determine differences in scapular/clavicular kinematics and activation levels of the upper, middle, and lower trapezius and serratus anterior muscles occurring during the exercises. RESULTS: The general pattern of the kinematics observed during all retraction exercises was scapular external rotation, scapular upward rotation, scapular posterior tilting, clavicular retraction, and clavicular depression. However, the exercises resulted in varying amounts of scapular movement and muscle activity. CONCLUSION: Clinicians can select appropriate exercises for their patients based on their need to strengthen specific retractor muscles and to improve specific scapular and clavicular movement patterns, pre-existing conditions, and available range of motion.

J Orthop Sports Phys Ther 2010;40(3):169-179, Epub 5 February 2010. doi:10.2519/jospt.2010.3018

KEY WORDS: rehabilitation, scapular dyskinesis, shoulder injury

Study Design: Case control group study.
Objectives: To compare scapular position and orientation between baseball players with and without pathologic internal impingement.
Background: Scapular dysfunction has been implicated as a contributor to throwing-related pathologic internal impingement of the shoulder due to its role in increasing the contact between the greater tuberosity and posterior-superior glenoid, thereby impinging the posterior rotator cuff tendon(s) and labrum. However, to date, no definitive data demonstrate this scapular dysfunction in throwing athletes. The purpose of this study was to assess, in a controlled laboratory environment, whether scapular position and orientation would be different in throwing athletes diagnosed with pathologic internal impingement than in a control group of throwing athletes.
Methods and Measures: Eleven throwing athletes diagnosed with pathologic internal impingement, using both clinical examination and a magnetic resonance arthrogram, were demographically matched with a control group of 11 throwers with no history of upper extremity injury. An electromagnetic tracking device was used to measure scapular internal/external rotation, anterior/ posterior tilt, upward/downward rotation, sternoclavicular protraction/retraction, and elevation/ depression during humeral elevation within the scapular plane. Comparisons were made between groups with analysis of variance models (P<.05).
Results: The individuals in the pathologic internal impingement group demonstrated statistically significant increased sternoclavicular elevation when elevating their humerus from 30° to 120° (P = .002) and from 60° to 120° (P = .003), compared to the control group. Furthermore, these patients also had increased posterior scapular tilt position (P = .016). No statistically significant differences were present in any other scapular variables measured.
Conclusions: Based on the results of this study, throwing athletes diagnosed with pathologic internal impingement present with statistically significant increases in sternoclavicular elevation and scapular posterior tilt position during humeral elevation in the scapular plane.

J Orthop Sports Phys Ther. 2006;36(7):485-494. doi:10.2519/jospt.2006.2146

Key Words: pathologic internal impingement, scapular kinematics, throwing athletes