The condition first known as ‘‘tennis elbow'' has been recognized for over a century. Typical signs and symptoms include pain and tenderness over the lateral epicondyle, exacerbated by resisted wrist extension and passive wrist flexion, and impaired grip strength. Although many tennis players may experience this condition, most cases are associated with work-related activities or have no obvious precipitating event. As a result, the term now most widely used is lateral epicondylitis. Yet, this name implies a pathological basis that is contrary to longstanding, albeit evolving, evidence that it is not an inflammatory condition. It is therefore recommended that it is time to adopt a new and more appropriate term, such as epicondylalgia (suffix algia means pain), that does not reflect such underlying pathology. This Journal has recently embraced this terminology.

J Orthop Sports Phys Ther. 2005; 35(4):200-202. doi:10.2519/jospt.2005.0104

Key Words: epicondylitis, lateral epicondylalgia, tennis elbow

Study Design: Cross-sectional. Objective: To investigate the association between lumbar segmental motion and pain response during the application of a posterior-to-anterior (PA) force to the lumbar spinous processes in persons with nonspecific low back pain. Background: Although low back pain is believed to be associated with altered segmental motion of the lumbar spine, the relationship between subjective reports of pain and objective measurements of segmental motion has not been established. Methods and Measures: Thirty-five individuals between 18 and 45 years of age with nonspecific low back pain (less than 3 months’ duration) participated. All subjects participated in 2 separate procedures: (1) segmental motion assessment during a PA force application over the lumbar spinous processes using dynamic magnetic resonance imaging (MRI), and (2) pain assessment during a PA force application procedure outside of the MRI environment. Frequency counts were used to determine the lumbar segments that were most painful, and which functional spinal units had the most and least motion. Fisher exact tests were performed to determine if an association existed between the most painful segment and the functional spinal unit with the most or least motion. Results: L5 was deemed the most painful segment in nearly half of the participants (48.1%). The L1-2 and L3-4 functional spinal units most frequently had the most motion (25.9% each) and the L4-5 functional spinal units most frequently had the least motion (29.6%). No association was found between the most painful segment and the functional spinal units with either the most or least motion. Conclusion: The results of this study indicate that an assumption regarding segmental motion cannot be inferred from the pain response when using a PA force application procedure.

J Orthop Sports Phys Ther. 2005;35(4):203-209. doi:10.2519/jospt.2005.1479

Key Words: lumbar spine, manual therapy, painful segment

Study Design: Randomized clinical trial. Objectives: To investigate the clinical efficacy of the addition of the Protonics system to a standard exercise-based patellofemoral rehabilitation protocol. Background: The Protonics system has been suggested as an intervention for patients with patellofemoral pain syndrome (PFPS). However, the effects of this system have not been compared to the effects associated with traditional exercise-based rehabilitation alone. Methods and Measures: Seventeen of 34 females (mean age, 28 years; range, 13-55 years) diagnosed with PFPS were randomly assigned to wear the Protonics system while participating in a conventional exercise-based rehabilitation program. Functional and patient-reported outcome measures were evaluated, including Kujala score and the lateral step-up test. In addition, measurements of hip internal and external rotation, hip extension, and iliotibial band muscle length were compared between groups. Results: Patients in both groups demonstrated improvement in Kujala score (P<.001), performance on the lateral step-up test (P<.001), and pain during the step-up test (P<.001) at the conclusion of the study. However, there was no difference between groups with respect to improvement in Kujala score (P = .33), step-up test performance (P = .47), or pain during the step-up test (P = .24). Patients using the Protonics system demonstrated greater gain in passive hip extension (P = .023) and increased hip external rotation motion (P = .017) at discharge versus patients treated with exercise alone. However, there was no difference in iliotibial band flexibility (P = .80) or hip internal rotation motion (P = .09) between groups. A greater proportion of patients in the Protonics group reported no pain with step-up testing at each 2-week interval. However, the 2.2 fewer visits required by patients in the Protonics group to meet discharge criteria did not achieve statistical significance (P = .08). Conclusions: Patients using the Protonics system demonstrated a shift in available hip rotation and increased passive hip extension flexibility. However, these changes were not outside the bounds of potential measurement error and did not translate into significant functional differences from a similar group treated with exercise alone. The economic implications of an average 2.2-visit decrease in treatment sessions per patient using the Protonics system are uncertain.

J Orthop Sports Phys Ther. 2005;35(4):210-219. doi:10.2519/jospt.2005.1566

Key Words: anterior knee pain, hip rotation, Kujala score, therapeutic exercise

Study Design: One-group, prospective, cross-sectional study. Objectives: To determine how sensorimotor function, balance, and physical performance are associated with disability and walking capacity in patients with lumbar spinal stenosis. Background: Patients with lumbar spinal stenosis often report disability and limited walking capacity. Identification of associated factors could provide information for future investigations leading to better prevention and intervention strategies. Methods and Measures: Fifty patients with lumbar spinal stenosis answered questions regarding symptom intensity, disability, and walking capacity. Muscle strength and vibration sense were assessed to represent sensorimotor function. Balance ability was measured by single-leg stance time and basic physical performance was tested by the up-and-go (UG) test. Regression analyses, entering demographics and symptom intensity as control variables, and sensory, strength, balance, and physical performance as additional independent variables, were conducted separately for disability and walking capacity. Results: Symptom intensity, vibration sense at the big toe, and UG test time were significantly correlated with disability. The final regression model showed that the control variables explained 20% of the variance, while vibration sense and UG test time explained an additional 20% of the variance. Walking capacity was significantly correlated with vibration sense at the big toe and UG test time. No significant regression model emerged for walking capacity. Conclusions: A moderate amount of variance in disability could be explained by sensory function at the big toe and physical performance. These factors should be considered in future research.

J Orthop Sports Phys Ther. 2005;35(4):220-226. doi:10.2519/jospt.2005.1613

Key Words: low back pain, muscle strength, sensory function

Study Design: Two-group comparison. Objective: To compare scapular kinematics during arm elevation between groups distinguished by pectoralis minor resting length. Background: Studies have demonstrated that individuals with subacromial impingement have altered scapular kinematics, such as loss of posterior tipping and increased internal rotation. One proposed mechanism for these alterations is an adaptively short pectoralis minor. This anterior scapulothoracic muscle may impact normal scapular kinematics if adaptively short. Methods and Measures: Fifty volunteers without shoulder pain were divided into long or short groups according to normalized pectoralis minor resting length. An electromagnetic motion capture system determined the angular orientation of the scapula, humerus, and trunk during arm elevation in 3 separate planes. Groups were compared for 3-dimensional scapular orientation relative to the trunk at arm elevation angles of 30°, 60°, 90°, and 120°, using a mixed-model analysis of variance (ANOVA). Results: There were statistically significant interaction effects between group and arm elevation angle for scapular tipping in all planes of arm elevation, with the scapula for the short group staying anteriorly tipped at higher angles. There was also a significant interaction for scapular internal rotation at lower arm elevation angles in the coronal plane only, with individuals with a shorter pectoralis minor demonstrating a more internally rotated scapula. Conclusions: The group distinguished by a short pectoralis minor demonstrated scapular kinematics similar to the kinematics exhibited in earlier studies by subjects with shoulder impingement. These results support the theory that an adaptively short pectoralis minor may influence scapular kinematics and is therefore a potential mechanism for subacromial impingement.

J Orthop Sports Phys Ther. 2005;35(4):227-238. doi:10.2519/jospt.2005.1669

Key Words: biomechanics, impingement, muscle, shoulder, 3-dimensional

Study Design: Independent group design, 1 group per carrier frequency, with subjects stratified by gender and systematically assigned to groups. Objective: To determine the effect of the frequency of burst-modulated alternating current (AC) on the electrically induced torque (EIT) response of the quadriceps femoris muscle. Background: Many studies have examined the influence of current amplitude and burst modulation on the EIT response. However, research is limited on the effects of carrier frequency on the EIT response of the quadriceps femoris. Methods and Measures: Twenty-three healthy subjects (mean age ± SD, 22.7 ± 1.7 years) volunteered for the study and were systematically assigned to 1 of 3 groups: group 1 (2500-Hz AC), group 2 (3750-Hz AC), and group 3 (5000-Hz AC). For normalization purposes, maximal voluntary isometric contraction (MVIC) force was assessed with a load cell prior to the application of 5 minutes of neuromuscular electrical stimulation (NMES). The EIT and current amplitude were recorded during each of the 5 minutes of NMES. Results: The mean EIT ([EIT/MVIC] × 100) produced at equivalent current amplitudes when using the 2500-Hz carrier frequency was significantly greater than the mean EITs generated at 3750 Hz (P = .004) and 5000 Hz (P<.001), respectively. Conclusions: Burst-modulated alternating current delivered at 2500 Hz produced greater EITs than those generated at 3750 and 5000 Hz.

J Orthop Sports Phys Ther. 2005;35(4):239-245. doi:10.2519/jospt.2005.1779

Key Words: current amplitude, electrical muscle stimulation, muscle training intensity

Study Design: Cross-sectional descriptive study. Objectives: To examine the factors of gender and age, stratified by 10-year increments, on hamstring muscle length (HML) as measured by passive straight leg raise (PSLR) and popliteal angle (PA). Background: Differences in HML between men and women have not been examined for a large group of healthy adults over a wide range of ages. The usefulness of these data is to provide some typical values of HML for future reference. Methods and Measures: Two hundred fourteen adults (108 women, 106 men; age range, 20-79 years) with no known history of hip or knee joint disease and no history of recent hamstring strain participated in the study. PSLR (trunk-thigh angle) and PA (thigh-leg angle) were estimated with a goniometer. A 2-way analysis of variance (ANOVA) was used to analyze the effects of 2 independent variables (gender and age) on 2 dependent variables (PSLR and PA). Statistical significance was established at a<.05. Results: HML differed significantly (P<.001) between genders for both methods of measurement, with females demonstrating greater flexibility than their male counterparts. The difference between genders was 8° for PSLR and 11° for PA. HML was not influenced by age. Conclusions: This study provides physical therapists with typical values of HML in healthy men and women.

J Orthop Sports Phys Ther. 2005;35(4):246-252. doi:10.2519/jospt.2005.1428

Key Words: flexibility, hip extensors, lower extremity, straight-leg raise