Some factors predict successful short-term outcomes in individuals with shoulder pain receiving cervicothoracic manipulation: a single-arm trial.

BACKGROUND: It has been reported that manipulative therapy directed at the cervical and thoracic spine may improve outcomes in patients with shoulder pain. To date, limited data are available to help physical therapists determine which patients with shoulder pain may experience changes in pain and disability following the application of these interventions. OBJECTIVE: The purpose of this study was to identify prognostic factors from the history and physical examination in individuals with shoulder pain who are likely to experience rapid improvement in pain and disability following cervical and thoracic spine manipulation. DESIGN: This was a prospective single-arm trial. SETTING: This study was conducted in outpatient physical therapy clinics. PARTICIPANTS: The participants were individuals who were seen by physical therapists for a primary complaint of shoulder pain. INTERVENTION AND MEASUREMENTS: Participants underwent a standardized examination and then a series of thrust and nonthrust manipulations directed toward the cervicothoracic spine. Individuals were classified as having achieved a successful outcome at the second and third sessions based on their perceived recovery. Potential prognostic variables were entered into a stepwise logistic regression model to determine the most accurate set of variables for prediction of treatment success. RESULTS: Data for 80 individuals were included in the data analysis, of which 49 had a successful outcome. Five prognostic variables were retained in the final regression model. If 3 of the 5 variables were present, the chance of achieving a successful outcome improved from 61% to 89% (positive likelihood ratio=5.3). LIMITATIONS: A prospective single-arm trial lacking a control group does not allow for inferences to be made regarding cause and effect. The statistical procedures used may result in "overfitting" of the model, which can result in low precision of the prediction accuracy, and the bivariate analysis may have resulted in the rejection of some important variables. CONCLUSIONS: The identified prognostic variables will allow clinicians to make an a priori identification of individuals with shoulder pain who are likely to experience short-term improvement with cervical and thoracic spine manipulation. Future studies are necessary to validate these findings.

Predicting short-term response to thrust and nonthrust manipulation and exercise in patients post inversion ankle sprain.

STUDY DESIGN: Prospective-cohort/predictive-validity study. OBJECTIVES: To develop a clinical prediction rule (CPR) to identify patients who had sustained an inversion ankle sprain who would likely benefit from manual therapy and exercise. BACKGROUND: No studies have investigated the predictive value of items from the clinical examination to identify patients with ankle sprains likely to benefit from manual therapy and general mobility exercises. METHODS AND MEASURES: Consecutive patients with a status of post inversion ankle sprain underwent a standardized examination followed by manual therapy (both thrust and nonthrust manipulation) and general mobility exercises. Patients were classified as having experienced a successful outcome at the second and third sessions based on their perceived recovery. Potential predictor variables were entered into a stepwise logistic regression model to determine the most accurate set of variables for prediction of treatment success. RESULTS: Eighty-five patients were included in the data analysis, of which 64 had a successful outcome (75%). A CPR with 4 variables was identified. If 3 of the 4 variables were present the accuracy of the rule was maximized (positive likelihood ratio, 5.9; 95% CI: 1.1, 41.6) and the posttest probability of success increased to 95%. CONCLUSIONS: The CPR provides the ability to a priori identify patients with an inversion ankle sprain who are likely to exhibit rapid and dramatic short-term success with a treatment approach, including manual therapy and general mobility exercises. LEVEL OF EVIDENCE: Prognosis, level 2b.

A biomechanical analysis of youth pitching mechanics.

BACKGROUND: It is estimated that nearly 6% of youth baseball participants seek medical attention for injuries sustained during play. Most injuries are overuse injuries, and 26% are to the shoulder or upper arm. By quantifying youth pitching biomechanics, knowledge can be gained concerning the manner in which these injuries are sustained during play. METHODS: Sixteen healthy right hand-dominant baseball pitchers participated in this study. After digitization of 21 bony landmarks, kinematic calculations were conducted using the 3-dimensional coordinates from each video frame. Data were time normalized, forcing major temporal components of the movement to occur at specific intervals. Segment-based reference frames were established, and resultant joint kinetics were projected onto each reference frame. Kinetic data were normalized and calculated along or about the anterior/posterior, medial/lateral, and proximal/distal axes. RESULTS: Maximum trunk rotation and external shoulder rotation were observed during arm cocking. Each of the remaining kinematic parameters peaked after ball release. All maximum values for joint kinetics were measured during arm cocking with the exception of compressive forces experienced at the shoulder and elbow, which peaked after the instant of ball release. CONCLUSIONS: Data produced in this study indicate that youth pitchers initiate trunk rotation early in the movement, which can lead to shoulder hyperangulation. Opposing torques at each end of the humerus also produce a large net torque about the longitudinal axis of the humerus during late arm cocking and may increase humeral retrotorsion in youth pitchers. Underdeveloped musculature in the rotator cuff may lead to difficulty controlling throwing-arm deceleration, causing an increase in horizontal adduction across the torso. CLINICAL RELEVANCE: An improved understanding of youth pitching mechanics is gained from the data collected, analyzed, and discussed in this study. Through increases in the knowledge pertaining specifically to the mechanics of youth pitchers, the opportunity to develop pitching mechanics specifically designed for preventing injuries in little league pitchers arises. LEVEL OF EVIDENCE: This study is a Level 4 study describing youth pitching biomechanics and how they relate to possible injuries.