Results of this study indicate that people with unstable shoulders can perceive shoulder angles as accurately as people with healthy shoulders in activities with voluntary arm movements. Compared with passive matching, better information from muscle spindles and other sources during voluntary arm movements may compensate for the potential joint position sense deficits after the injury. Therefore, individuals with an unstable shoulder may have adequate neuromuscular control to engage proper protective mechanisms to stabilize the shoulder joint during functional activities.

Lateral ankle sprain is a common orthopedic injury with a very high recurrence rate in athletes. After decades of research, it is still unclear what contributes to the high recurrence rate of ankle sprain, and what is the most effective intervention to reduce the incident of initial and recurrent injuries. In addition, clinicians often implement balance training as part of the rehabilitation protocol in hopes of enhancing the neuromuscular control and proprioception of the ankle joint. However, there is no consensus on whether the neuromuscular control and proprioception are compromised in unstable ankles. To reduce the prevalence of ankle sprains, the effectiveness of engaging balance training to enhance the neuromuscular control and proprioception of the ankle joint is also questionable. Core tip: Lateral ankle sprain is a common orthopedic injury with a high recurrence rate. However, there is no consensus on whether neuromuscular control and proprioception are compromised in unstable ankles, and whether proprioception training can reduce initial and recurrent ankle injuries. The purpose of this review is to discuss the etiology and intervention of initial and recurrent ankle sprains, focusing on the role of neuromuscular control and proprioception at the ankle joint. This review can provide clinicians the knowledge of constructing better examination protocols and rehabilitation programs for individuals with the unstable ankle.Hung Y. Neuromuscular control and rehabilitation of the unstable ankle. World J Orthop 2015; 6(5): 434-438 Available from: URL:

Background and purposeBody composition evaluation during health screenings and physical examination is important for health professionals (including physical therapists) to categorize health risk and prescribe appropriate exercise interventions. In addition to measuring bone mineral density, dual energy x-ray absorptiometry (DXA) can provide precise measurement of body fat percentage with minimal radiation exposure. However, having access to DXA is very costly and other common body fat measurements are no very accurate. The purpose of this study was to develop body fat prediction equations for bioelectrical impedance analysis (BIA) and skinfold measurement, using DXA data as the criterion. MethodsThis was a within-group study with repeated measures. Sixty three college age students participated in the study. Subject's body fat percentage was examined with DXA, BIA, and the 3-site skinfold measurements. ResultsBody fat percentage measured with DXA (26.27%) is significantly higher than those measured with skinfold (17.64%) and BIA (20.70%). The DXA criterion regression equations were created for skinfold and BIA: DXA%BF=4.65+0.43 * S3SF (sum of 3 site skinfold in mm); DXA%BF=3.79+1.09 * BIA%BF. The new regression equations were further validated using 75%-25%subject cross-validation. DiscussionBody fat percentage varies greatly among different measurements. Adjustments are necessary to accurately predict body fat percentage when using skinfold or BIA techniques at a clinical setting. The limitation of the study is that it is unclear if the results can be generalized to subjects of a different age group and ethnicities. Implication for physiotherapy practiceObtaining an accurate body fat percentage measurement is important for health promotion and cardiovascular risk screening. Although skin-fold and BIA equipment are more readily available, their results underestimate the body fat percentage and may mislead clinicians on the wellbeing of the patient.

The purpose of this report was to investigate whether a subject with anterior shoulder instability exhibited better active shoulder position sense and 3-dimensional (3-D) reaching accuracy after a surgical repair. The 19-year-old male subject underwent an open Bankart repair procedure for his left shoulder followed by a standardized post-operative rehabilitation program. Shoulder position sense was examined with traditional passive matching and active positioning protocols. Reaching accuracy in space with the unrestricted arm motion was also examined. The subject was tested 5 months prior to the surgery and re-tested 6 months after the surgery. With the traditional passive matching protocol, shoulder position sense improved <2° after surgery. However, shoulder position sense improved greatly after surgery with active shoulder abduction (up to 4.25°) and active shoulder rotation (up to 5.87°) testing protocols. In addition, reaching accuracy also greatly improved after surgery (up to 10.97 cm) with the most significant improvement when reaching to targets located in the frontal plane. Data suggest that anterior shoulder repair with rehabilitation can improve both active shoulder position sense and reaching accuracy, especially in shoulder positions involving abduction with external rotation.

AIMTo investigate the impact of extrinsic visual feedback and additional cognitive/physical demands on single-limb balance in individuals with ankle instability.METHODSSixteen subjects with ankle instability participated in the study. Ankle instability was identified using the Cumberland Ankle Instability Tool (CAIT). The subject’s unstable ankle was examined using the Athletic Single Leg Stability Test of the Biodex Balance System with 4 different protocols: (1) default setting with extrinsic visual feedback from the monitor; (2) no extrinsic visual feedback; (3) no extrinsic visual feedback with cognitive demands; and (4) no extrinsic visual feedback with physical demands. For the protocol with added cognitive demands, subjects were asked to continue subtracting 7 from a given number while performing the same test without extrinsic visual feedback. For the protocol with added physical demands, subjects were asked to pass and catch a basketball to and from the examiner while performing the same modified test.RESULTSThe subject’s single-limb postural control varied significantly among different testing protocols (F = 103; P = 0.000). Subjects’ postural control was the worst with added physical demands and the best with the default condition with extrinsic visual feedback. Pairwise comparison shows subjects performed significantly worse in all modified protocols (P < 0.01 in all comparisons) compared to the default protocol. Results from all 4 protocols are significantly different from each other (P < 0.01) except for the comparison between the “no extrinsic visual feedback” and “no extrinsic visual feedback with cognitive demands” protocols. Comparing conditions without extrinsic visual feedback, adding a cognitive demand did not significantly compromise single-limb balance control but adding a physical demand did. Scores from the default protocol are significantly correlated with the results from all 3 modified protocols: No extrinsic visual feedback (r = 0.782; P = 0.000); no extrinsic visual feedback with cognitive demands (r = 0.569; P = 0.022); no extrinsic visual feedback with physical demands (r = 0.683; P = 0.004). However, the CAIT score is not significantly correlated with the single-limb balance control from any of the 4 protocols: Default with extrinsic visual feedback (r = -0.210; P = 0.434); no extrinsic visual feedback (r = -0.450; P = 0.081); no extrinsic visual feedback with cognitive demands (r = -0.406; P = 0.118); no extrinsic visual feedback with physical demands (r = -0.351; P = 0.182).CONCLUSIONSingle-limb balance control is worse without extrinsic visual feedback and/or with cognitive/physical demands. The balance test may not be a valid tool to examine ankle instability.