Study Design: Case control study.

Objectives: The objectives of this study are: (1) to perform factor analyses on data from the 8 components of the star excursion balance test (SEBT) in subjects with and without chronic ankle instability (CAI) in an effort to reduce the number of components of the SEBT, (2) to assess the relationships between performance of the different reach directions using correlation analyses, and (3) to determine which components of the SEBT are most affected by CAI.

Background: The SEBT is a series of 8 lower-extremity–reaching tasks purported to be useful in identifying lower extremity functional deficits.

Methods and Measures: Forty-eight young adults with unilateral CAI (22 males, 26 females; mean ± SD age, 20.9 ± 3.2 years; mean ± SD height, 173.6 ± 11.1 cm; mean ± SD mass, 80.1 ± 22.1 kg) and 39 controls (23 males, 16 females; mean ± SD age, 20.7 ± 2.4 years; mean ± SD height, 174.1 ± 12.9 cm; mean ± SD mass, 75.1 ± 18.6 kg) performed 3 trials of the 8 tasks with each of their limbs. Separate exploratory factor analyses were performed on data for involved limbs of the CAI group, uninvolved limbs of the CAI and control groups, and both limbs of the CAI and control groups. Pearson product moment correlations were calculated to identify the relationships between the different reach directions. A series of eight 2 × 2 analyses of variance were calculated to determine the influence of group (CAI, control) and side (involved, uninvolved) on performance of the 8 tasks.

Results: For all 3 factor analyses, only 1 factor in each analysis produced an eigenvalue greater than 1 and the posteromedial reach score was the most strongly correlated task with the computed factor (α>.90), although all 8 tasks produced alpha scores greater than .67. Bivariate correlations between specific reach directions ranged from .40 to .91. Subjects with CAI reached significantly less on the anteromedial, medial, and posteromedial directions when balancing on their involved limbs compared to their uninvolved limbs and the side-matched limbs of controls.

Conclusions: The posteromedial component of the SEBT is highly representative of the performance of all 8 components of the test in limbs with and without CAI. There is considerable redundancy in the 8 tasks. The anteromedial, medial, and posteromedial reach tasks may be used clinically to test for functional deficits related to CAI in lieu of testing all 8 tasks. There is a need for a hypothesis-driven study to confirm the results of this exploratory study. J Orthop Sports Phys Ther. 2006;36(3):131-137.

Key Words: dynamic postural control, functional testing, lower extremity

Study Design: Case series.

Objectives: To describe an established method of diagnosing cervical radiculopathy (CR) using a clinical prediction rule (CPR), and to describe the management of 6 patients using intermittent cervical traction (ICT), thoracic thrust joint manipulation (TJM), and exercise.

Background: Many patients present with unilateral arm pain without having undergone magnetic resonance imaging (MRI) of the cervical spine. Using a CPR has demonstrated high levels of specificity to rule in cervical radiculopathy. ICT and manual therapy (including thoracic TJM) are widely used in clinical settings to treat cervical radiculopathy.

Case description: Six patients (3 men, 3 women) were diagnosed with cervical radiculopathy using the CPR. All patients were treated with ICT, thoracic TJM, and exercise. The Northwick Park Neck Questionnaire served as the outcome measure.

Outcomes: The CPR accurately identified CR (secondary to a disc herniation) in 4 out of 4 patients when compared to the results of a reference standard (MRI). Six patients were seen from 5 to 18 sessions over a 19- to 56-day period. Reduction in Northwick Park Neck Questionnaire scores ranged from 13% to 88%. One patient did not improve significantly and underwent neck surgery.

Discussion: Using the CPR may be beneficial in diagnosing CR, so the clinician can devise a plan of care and assess treatment outcomes in a relatively homogenous group of patients. It is possible that a treatment regimen of ICT, thoracic TJM, and exercise will aid in centralizing radicular symptoms and improving functional outcomes in patients with CR. J Orthop Sports Phys Ther. 2006;36(3):152-159.

Key Words: cervical spine, intermittent traction, thoracic thrust joint manipulation

Study Design: Semiexperimental study.

Objective: To investigate the effect of an external wrist extension force on extensor muscle activity during hand gripping in patients with lateral epicondylalgia.

Background: Lateral epicondylalgia or ‘‘tennis elbow’’ is a common, often disabling ailment affecting millions of people. An optimal treatment strategy remains to be identified. The use of an external wrist extension force may reduce the extensor muscle activity during gripping in these patients.

Methods: Muscle activity of the extensor carpi radialis brevis (ECRB), extensor digitorum communis (EDC), and extensor carpi radialis longus (ECRL) was measured using surface EMG. Subjects gripped at an intensity of 10%, 20%, and 30% of the maximum voluntary contraction (MVC) force with and without the dynamic extensor brace and with and without an applied external wrist extension force of 1%, 2%, and 3% of MVC.

Results: At all levels of MVC gripping, the EMG signal of the ECRB and EDC were significantly lower for gripping with than without brace. An extension force of 3% of the MVC force significantly reduced the EMG signal of all muscles in almost all measurement conditions.

Conclusions: The results of this study indicate that the dynamic extensor brace as well as the external extension force significantly reduced the EMG signal of the wrist extensor muscles during gripping in patients with lateral epicondylalgia. Based on these results, the dynamic extensor brace could be a promising new intervention for lateral epicondylalgia. J Orthop Sports Phys Ther. 2006;36(3):170-178.

Key Words: electromyography, hand grip, isometric force, tennis elbow