implementation of CKC activities along with traditional OKC therapeutic exercise interventions within a program geared toward prevention or treatment of shoulder instability or dysfunction would most likely not decrease positive outcomes of the prospective rehabilitation program. As this study utilized young, (16 years old) uninjured subjects who were exclusively male and thus, make it difficult to translate the findings across a general patient population. Further studies of this type should be completed across a more diverse patient population regarding patient sex, age and activity level as well as implementation of complete treatment protocol incorporating multiple interventions more geared to challenge proprioceptive capability of the patient. References: 1. Western Michigan University. Table of critical values for the F distribution (for use with ANOVA). Assessed 11/20/2014 http://homepages.wmich.edu/~hillenbr/619/AnovaTable.pdf 2. Statistical Solutions, LLC. Power and Sample Size Calculator. Updated 2014, assessed 11/20/2014. http://www.statisticalsolutions.net/pss_calc.php 3. Lephart S.M et al. Proprioception of the shoulderjoint in healthy, unstable and surgically repaired shoulders. Journal of shoulder and elbow surg, 1994;volume 3:371-380 4. Dillman C.J et al. Biomechanical differences open and closed chain exercises with respect to the shoulder. Journal of sport and rehabilitation, 1994;volume 3:228-238

## IMPLICATIONS FOR PRACTICE and FUTURE RESEARCH

There exists a multitude of evidence, which indicate a moderate to strong correlation regarding core stability, balance capability and the presence of acute injury or chronic shoulder dysfunction amongst overhead athletes. However these studies are most often not clinical trials without pre and post testing but rather repeated measures of core stability among a single cohort. Specific to the activity of rock-climbing, most of the available evidence are based upon rate of traumatic injuries associated with the sport or curtailed to the wrist and hand specifically, the injury and pathology associated with the flexor pulley/tendon complex associated with assuming the “crimp-grip” position. There is widespread implementation of CKC exercise, core stability and means of challenging both at the trunk and GHJ/STJ via perturbation-like challenges. Closed-chain exercise protocols are felt to be preferable to other exercise programs in that they simulate normal physiologic and biomechanical functions, create little shear stress across injured or healing joints and reproduce proprioceptive stimuli. Due to these advantages, they are used during early rehabilitation and have been integral parts of accelerated programs.1 rehabilitation Specific to the shoulder methods of incorporating CKC and perturbation-based challenge include but not limited to rhythmic stabilization, the use of foam-mats, Swiss-balls, multi- sensory balance training or various modifications of the patients base of support such as single-leg stance, semi-tandem and tandem stances. There is no increased cost with utilizing these types of interventions with necessary equipment to implement these types of interventions being readily available within the normal outpatient rehabilitation setting. Furthermore, there is strong evidence, which shows that those who are active participants in the activity of rock-climbing could be predisposed to shoulder pathology and dislocation. This is due to activity-induced muscle imbalance, with hypertrophy of muscle-tendon units which extend, adduct and shoulder-joint.2 internally rotate the Clinicians should become more familiar with the sport of rock- climbing and the style of functional movement this activity encompasses to facilitate an understanding of prospective mechanisms of injury and implement a more patient-centered plan of care. Based on quasi-static equilibrium, climbing is a dynamic and controlled upward or lateral movement of a bodies COM. This is achieved through continuous postural/proximal joint stability, automatic postural reactions, anticipatory postural adjustments, coordination of movements composed of open kinematic chain (OKC) as well as closed kinematic chain (CKC) motion, and continuous to intermittent maximal