Jennifer Stiller and Timothy L. Uhl
Column-editor : Carl G. Mattacola
Richard N. Hinrichs
Ten male recreational runners were filmed using three-dimensional cinematography while running on a treadmill at 3.8 m/s, 4.5 m/s, and 5.4 m/s. A 14-segment mathematical model was used to examine the contributions of the arms to the total-body angular momentum about three orthogonal axes passing through the body center of mass. The results showed that while the body possessed varying amounts of angular momentum about all three coordinate axes, the arms made a meaningful contribution to only the vertical component (Hz). The arms were found to generate an alternating positive and negative Hz pattern during the running cycle. This tended to cancel out an opposite Hz pattern of the legs. The trunk was found to be an active participant in this balance of angular momentum, the upper trunk rotating back and forth with the arms and, to a lesser extent, the lower trunk with the legs. The result was a relatively small total-body Hz throughout the running cycle. The inverse relationship between upper- and lower-body angular momentum suggests that the arms and upper trunk provide the majority of the angular impulse about the z axis needed to put the legs through their alternating strides in running.
Richard N. Hinrichs, Peter R. Cavanagh and Keith R. Williams
Ten male recreational runners were filmed using three-dimensional cinematography while running on a treadmill at 3.8 m/s, 4.5 m/s, and 5.4 m/s. A 14-segment mathematical model was used to examine the influence of the arm swing on the three-dimensional motion of the body center of mass (CM), and on the vertical and horizontal propulsive impulses (“lift” and “drive”) on the body over the contact phase of the running cycle. The arms were found to reduce the horizontal excursions of the body CM both front to back and side to side, thus tending to make a runner's horizontal velocity more constant. The vertical range of motion of the body CM was increased by the action of the arms. The arms were found to make a small but important contribution to lift, roughly 5–10% of the total. This contribution increased with running speed. The arms were generally not found to contribute to drive, although considerable variation existed between subjects. Consistent with the CM results, the arms were found to reduce the changes in forward velocity of the runner rather than increasing them. It was concluded that there is no apparent advantage of the “classic” style of swinging the arms directly forward and backward over the style that most distance runners adopt of letting the arms cross over slightly in front. The crossover, in fact, helps reduce side-to-side excursions of the body CM mentioned above, hence promoting a more constant horizontal velocity.
Shana Harrington, Corinne Meisel and Angela Tate
The prevalence of shoulder pain in the competitive swimming population has been reported to be as high as 91%. Female collegiate swimmers have a reported shoulder-injury rate 3 times greater than their male counterparts. There has been little information on how to best prevent shoulder pain in this population. The purpose of this study was to examine if differences exist in shoulder range of motion, upper-extremity strength, core endurance, and pectoralis minor length in NCAA Division I female swimmers with and without shoulder pain and disability.
NCAA Division I females (N = 37) currently swimming completed a brief survey that included the pain subscale of the Penn Shoulder Score (PSS) and the sports/performing arts module of the Disabilities of the Arm, Shoulder, and Hand (DASH) Outcome Measure. Passive range of motion for shoulder internal rotation (IR) and external rotation (ER) at 90° abduction was measured using a digital inclinometer. Strength was measured using a handheld dynamometer for scapular depression and adduction, scapular adduction, IR, and ER. Core endurance was assessed using the side-bridge and prone-bridge tests. Pectoralis minor muscle length was assessed in both a resting and a stretched position using the PALM palpation meter. All measures were taken on the dominant and nondominant arms.
Participants were classified as positive for pain and disability if the following 2 criteria were met: The DASH sports module score was >6/20 points and the PSS strenuous pain score was ≥4/10. If these criteria were not met, participants were classified as negative for pain and disability. Significant differences were found between the 2 groups on the dominant side for pectoralis muscle length at rest (P = .003) and stretch (P = .029).
The results provide preliminary evidence regarding an association between a decrease in pectoralis minor length and shoulder pain and disability in Division I female swimmers.
Matthew B.A. McCullough, Brian D. Adams and Nicole M. Grosland
Third-generation total wrist arthroplasty devices have provided joint stability, relief from pain and increased wrist motion for patients suffering from severe arthritis. While reports of clinical follow-up appointments describe improved wrist function, the improvement in overall upper extremity function and patient perception remains a question. Therefore, the purpose of this study was to assess the upper extremity function in patients that received the Universal 2 total implant system. Eight patients participated in the complete protocol, which included testing activities of daily living as well as surveys to assess patient perception. The findings of the current study suggest that although patients exhibit motion that exceeds the needed amount, many still have a perceived disability.
Scott M. Lephart and Timothy J. Henry
The confusion between the terms open kinetic chain and closed kinetic chain becomes even greater with application to the upper extremity. Upper extremity function is very difficult to define, due to the numerous shoulder positions and the great velocities with which the shoulder can move. Classifying exercises for rehabilitation of the upper extremity is very difficult due to the complexity of the joint. Many definitions and classification systems have been proposed; however, none of these entirely encompass rehabilitation of the upper extremity. Using previous classifications we have developed a Functional Classification System that is designed to serve as a template for upper extremity rehabilitation. This system has been designed to restore functional shoulder stability, which is dependent upon proper scapulothoracic and glenohumeral stability, and humeral control; all of these are in part mediated by neuromuscular mechanisms. The objective of our new Functional Classification System is to restore functional stability of the shoulder by reestablishing neuromuscular control for overhead activities.
Anthony C. Santago II, Meghan E. Vidt, Xiaotong Li, Christopher J. Tuohy, Gary G. Poehling, Michael T. Freehill and Katherine R. Saul
to identifying individuals at risk for future disability due to strength loss, and ultimately for providing strategies that preserve and improve upper extremity function. Therefore, the objectives of this study were to: (1) quantify required shoulder strength to complete 5 common functional tasks
Bryan L. Riemann and George J. Davies
-arm shot-put functional performance test . J Athl Train . 2018 ; 53 ( 10 ): 976 – 982 . PubMed ID: 30299159 doi: 10.4085/1062-6050-388-17 30299159 2. Negrete RJ , Hanney WJ , Kolber MJ , et al . Reliability, minimal detectable change, and normative values for tests of upper extremity function
Shani Batcir and Itshak Melzer
functional scores of LLFDI (overall function, upper-extremity function, and basic and advanced lower-extremity functions). A significance level of 0.05 was used. Results There were no significant differences in age, gender, height, weight, number of falls, and medications per day, as well as upper
Mark G.L. Sayers and Stephen Bishop
, Hanney WJ , Kolber MJ , et al . Reliability, minimal detectable change, and normative values for tests of upper extremity function and power . J Strength Cond Res. 2010 ; 24 ( 12 ), 3318 – 3325 . PubMed doi: 10.1519/JSC.0b013e3181e7259c 21088548 10.1519/JSC.0b013e3181e7259c 28. van den Tillaar