James W. Youdas

Reliability of goniometric measurements and visual estimates of ankle joint active range of motion obtained in a clinical setting

We examined intratester and intertester reliability for goniometric measurements of ankle dorsiflexion (ADF) and ankle plantar flexion (APF) active range of motion (AROM). Parallel-forms intratester reliability for ankle AROM measurements obtained by the universal goniometer (UG) and by visual estimation (VE) and intertester reliability for VE of ADF and APF were examined. Repeated measurements were obtained on 38 patients with orthopedic problems by 10 physical therapists in a clinical setting. For intratester reliability of measurements obtained with UG, intraclass correlation coefficients (ICC) for all physical therapists were 0.64 to 0.92 (median, 0.825) for ADF and 0.47 to 0.96 (median, 0.865) for APF. Intertester reliability was quantified with use of ICC. ICCs for measurements obtained by UG were 0.28 for ADF and 0.25 for APF; ICC of VE for ADF was 0.34 and was 0.48 for APF. ICC for parallel-forms intratester reliability obtained with UG and VE ranged from 0 to 0.94 (median, 0.58) for ADF and 0 to 0.86 (median, 0.625) for APF. Thus, a physical therapist should use a goniometer when making repeated measurements of ankle joint AROM. Considerable inconsistency exists when two or more physical therapists make repeated goniometric and visual measurements of ankle motion on the same subject. Physical therapists may erroneously conclude that a patients AROM has changed because of treatment when the change could be attributed to a lack of intertester reliability.

Peer Teaching among Physical Therapy Students during Human Gross Anatomy: Perceptions of Peer Teachers and Students.

Despite nearly 200 accredited entry‐level physical therapist education programs in the United States that culminate in a doctoral degree, only a paucity of reports have been published regarding the efficacy of peer teaching in gross anatomy. No one has described the usefulness of peer teaching from the viewpoint of the peer teacher. An organized peer teaching method provided by four second‐year doctors of physical therapy (DPT) students in a semester course in gross anatomy had a positive impact on the academic performance in gross anatomy of first‐year DPT students. The unique feature of the weekly peer teaching sessions was a packet assembled by the second‐year peer teachers, which contained diagrams, fill‐in‐the blank questions, and helpful mnemonic devices. This study surveyed perceptions of first‐year DPT students in response to a peer teaching method, using a structured 10‐item questionnaire and a five‐point Likert scale. Second‐year DPT peer teachers provided written reflections about the benefits and challenges of serving as a peer teacher. Results revealed that 13 planned peer‐teaching experiences provided by four second‐year DPT students were valuable and promoted a firm understanding of anatomical relationships important for the clinical competence of physical therapist students. Moreover, peer teachers acknowledged acquiring clinically desirable teaching, academic, organizational, and time management skills from the experience. As a result, physical therapist educators may wish to consider this model of peer teaching to augment their teaching strategies for a class in gross human anatomy. Anat Sci Ed 1:199–206, 2008.

The effects of gender, age, and body mass index on standing lumbar curvature in persons without current low back pain

Reference values for standing lumbar curvature (SLC) obtained via noninvasive methods are not well established in persons without current low back pain. The effect of gender is considered to have a significant effect on SLC with women having more lumbar lordosis than men. The effect of age and degree of obesity are not considered to have a statistically significant effect on SLC. The purpose of this study was to test the assumption that measurements of SLC in healthy adults obtained by a flexible curve will differ between genders, whereas the SLC will not differ across categories of age and body mass index (BMI). Two hundred thirty-five volunteers (119 men and 116 women) whose ages ranged between 20 and 79 years participated in the study. Subjects were almost exclusively White and from the Midwest. Measurements of the SLC were obtained by a flexible curve. The curves shape was transferred to poster board, and the value of SLC was quantified by a previously described technique. A three-way analysis of variance (α = 0.05) was used to examine the main effects of gender, age, and BMI on SLC. The effect of gender (F1,199 = 21.4, p < 0.0001) and the effect of age (F5,199 = 2.8, p < 0.017) were statistically significant. The effect of BMI (F2,199 = 1.8, p = 0.176) was not significant. Women (mean, 49.5°±10.7°) demonstrated about 6.5° more SLC than their male (mean, 43.0°±10.7°) counterparts. For age, the only significant difference was between the 20 to 29- and 50 to 59-year-old age categories. This study provides physical therapists with typical values of SLC in men and women without current low back pain.

RELIABILITY OF GONIOMETRIC MEASUREMENTS OF ACTIVE ARM ELEVATION IN THE SCAPULAR PLANE OBTAINED IN A CLINICAL SETTING

Our purpose was to determine the intratester and intertester reliability of measurements of both scapular and glenohumeral rotation during active arm elevation in the scapular plane with a new device, the scapulohumeral goniometer (SHG). Ten physical therapists, with 1 to 29 years of clinical experience, obtained repeated measurements on 45 subjects who were 27 to 82 years old. All subjects were tested in a uniform standing position with the handheld SHG, which was positioned over the subjects scapula and posterior shoulder according to operationally defined landmarks. For both scapular and glenohumeral rotation, 50% of the time the first and second measurements made on a patient by the same physical therapist differed by 3 degrees or more. Ten percent of the time, these measurements differed by 8 degrees or more. Measurements of active range of movement of scapular and glenohumeral rotation made by the same physical therapist during arm elevation in the scapular plane are clinically unacceptable when obtained with the current techniques for positioning the SHG. Clinical decisions based on results of active scapular and humeral motion in the scapular plane as measured on a patient by the same therapist with an SHG should be made with caution, because of the variability associated with this procedure.

Comparison of Muscle-activation Patterns During the Conventional Push-up and Perfect· Pushup™ Exercises

Youdas, JW, Budach, BD, Ellerbusch, JV, Stucky, CM, Wait, KR, and Hollman, JH. Comparison of muscle-activation patterns during the conventional push-up and perfect·pushup™ exercises. J Strength Cond Res 24(12): 3352-3362, 2010-Manufacturers of Perfect·Pushup™ handgrips claim enhanced muscular recruitment when compared with the conventional hand-on-floor push-up exercise. Electromyographic (EMG) data were recorded using surface electrodes from the right-sided triceps brachii, pectoralis major, serratus anterior (SA), and posterior deltoid muscles during push-ups performed from 3 different hand positions: (a) shoulder width, (b) wide base, and (c) narrow base (NB). Push-ups were performed under 2 conditions: (a) standard push-up and (b) Perfect·Pushup™ handgrips. We recruited 20 healthy subjects, 11 men (24.9 ± 2.6 years) and 9 women (23.8 ± 1 years). Subjects completed 3 consecutive push-ups for each hand position under both conditions. Push-up speed was controlled using a metronome, and testing order was randomized. We recorded peak EMG activity for each muscle during each of the push-ups and normalized EMG values by maximum muscle contractions (% maximum voluntary isometric contraction [MVIC]). Electromyographic data were analyzed with 3 (hand position) × 2 (condition) repeated-measures analysis of variance with a post hoc Bonferroni-adjusted simple effects test to detect significant position effects for position by condition interactions (α = 0.05). A push-up required considerable muscle activation of the triceps brachii (73-109% MVIC), pectoralis major (95-105% MVIC), SA (67-87% MVIC), and posterior deltoid (11-21% MVIC) whether performed using the conventional hand-on-floor position or the Perfect·Pushup™ handgrips. The NB hand position was most effective for preferentially activating the triceps brachii and posterior deltoid muscles. Based upon EMG activation from 4 muscles, the Perfect·Pushup™ handgrips do not appear to preferentially enhance muscular recruitment when compared with the conventional push-up method.

Gender differences in dual task gait performance in older adults.

Although attention-dividing dual tasks hinder gait performance in older persons, gender differences in gait have not been examined. The purpose of this study was to examine whether gait performance differs between older men and women during dual task walking. A total of 44 healthy adults (20 men and 24 women) aged 65 years or older participated in the study. Participants walked under normal and dual task (backward spelling) conditions at self-selected speeds. Mean gait speed and stride-to-stride variability in gait speed were quantified with GAITRite ® instrumentation. Whereas gait speed decreased and variability in gait speed increased in both groups during dual task walking, men walked with greater variability during dual task walking than did women. The magnitude of the increase in variability in gait speed observed in men indicates that stride-to-stride variability in gait speed during dual task walking requires more investigation as a potential risk factor for falls in older men.

Surface Electromyographic Activation Patterns and Elbow Joint Motion During a Pull-Up, Chin-Up, or Perfect-Pullup Rotational Exercise

Youdas, JW, Amundson, CL, Cicero, KS, Hahn, JJ, Harezlak, DT, and Hollman, JH. Surface electromyographic activation patterns and elbow joint motion during a pull-up, chin-up, or Perfect-Pullup™ rotational exercise. J Strength Cond Res 24(12): 3404-3414, 2010-This study compared a conventional pull-up and chin-up with a rotational exercise using Perfect·Pullup™ twisting handles. Twenty-one men (24.9 ± 2.4 years) and 4 women (23.5 ± 1 years) volunteered to participate. Electromyographic (EMG) signals were collected with DE-3.1 double-differential surface electrodes at a sampling frequency of 1,000 Hz. The EMG signals were normalized to peak activity in the maximum voluntary isometric contraction (MVIC) trial and expressed as a percentage. Motion analysis data of the elbow were obtained using Vicon Nexus software. One-factor repeated measures analysis of variance examined the muscle activation patterns and kinematic differences between the 3 pull-up exercises. Average EMG muscle activation values (%MVIC) were as follows: latissimus dorsi (117-130%), biceps brachii (78-96%), infraspinatus (71-79%), lower trapezius (45-56%), pectoralis major (44-57%), erector spinae (39-41%), and external oblique (31-35%). The pectoralis major and biceps brachii had significantly higher EMG activation during the chin-up than during the pull-up, whereas the lower trapezius was significantly more active during the pull-up. No differences were detected between the Perfect·Pullup™ with twisting handles and the conventional pull-up and chin-up exercises. The mean absolute elbow joint range of motion was 93.4 ± 14.6°, 100.6 ± 14.5°, and 99.8 ± 11.7° for the pull-up, chin-up, and rotational exercise using the Perfect·Pullup™ twisting handles, respectively. For each exercise condition, the timing of peak muscle activation was expressed as a percentage of the complete pull-up cycle. A general pattern of sequential activation occurred suggesting that pull-ups and chin-ups were initiated by the lower trapezius and pectoralis major and completed with biceps brachii and latissimus dorsi recruitment. The Perfect·Pullup™ rotational device does not appear to enhance muscular recruitment when compared to the conventional pull-up or chin-up.

Validity of hamstring muscle length assessment during the sit-and-reach test using an inclinometer to measure hip joint angle.

The aim of this study was twofold: (i) to describe the criterion-related validity of the sit-and-reach test (SRT) using a hand-held inclinometer when assessing hamstring muscle length (HML) when HML is recorded in degrees of hip joint angle (HJA); and (ii) to describe the effect of gender and age on HML in healthy adults during the performance of a SRT. We examined 212 healthy subjects (106 men and 106 women) whose ages ranged from 20 to 79 years. The Pearson-product moment correlation coefficient (r) described the relationship between HJA at the end-point of the SRT and the criterion, supine passive straight-leg raise (PSLR). We conducted a 6 × 2 analysis of variance, where age was stratified on 6 levels of 10-year increments (20-29, 30-39, 40-49, 50-59, 60-69, and 70-79 years of age) and gender was stratified on 2 levels (men and women). There was a statistically significant correlation (r = 0.59, P < 0.01) between performance on the SRT as measured by HJA and the supine PSLR, but the SRT only accounted for 35% of the variability in the PSLR. SRT performance in men (mean ± SD, 80 ± 9°) was significantly less (P < 0.001) than in women (mean ± SD, 92 ± 10°). Subjects in the 60- to 69- and 70- to 79-year age groups had significantly less (P < 0.05) HJA than those in the 20- to 29-, 30- to 39-, and 40- to 49-year age groups. Using an inclinometer to measure HJA during the SRT is not a valid method for assessing HML in men and women who can independently assume a long-sitting position on a hard surface. Clinicians should recognize there are differences in HML between men and women, and that men and women between 20 to 49 years of age have more HML than their counterparts between ages 60 to 79 years.

The efficacy of two modified proprioceptive neuromuscular facilitation stretching techniques in subjects with reduced hamstring muscle length.

Difference scores in knee extension angle and electromyographic (EMG) activity were quantified before and after modified proprioceptive neuromuscular facilitation (PNF) hold-relax (HR) and hold-relax-antagonist contraction (HR-AC) stretching procedures in 35 healthy individuals with reduced hamstring muscle length bilaterally (knee extension angle <160°). Participants were randomly assigned each PNF procedure to opposite lower extremities. Knee extension values were measured by using a goniometer. EMG data were collected for 10 seconds before and immediately after each PNF stretching technique and normalized to maximum voluntary isometric contraction (% MVIC). A significant time by stretch-type interaction was detected (F1,34 = 21.1; p < 0.001). Angles of knee extension for HR and HR-AC were not different prior to stretching (p = 0.45). Poststretch knee extension angle was greater in the HR-AC condition than the HR condition (p < 0.007). The proportion of subjects who exceeded the minimal detectable change (MDC95) with the HR-AC stretch (97%) did not differ (p = 0.07) from the proportion who exceeded the MDC95 with the HR stretch (80%). Because EMG activation increased (p < 0.013) after the HR-AC procedure, it is doubtful a relationship exists between range of motion improvement after stretching and inhibition of the hamstrings. On average the 10-second modified HR procedure produced an 11° gain in knee extension angle within a single stretch session.

Usefulness of the Trendelenburg test for identification of patients with hip joint osteoarthritis

Abstract This study examined validity indices of the Trendelenburg test as a measure of hip abductor muscle performance (adduction of pelvis-on-femur [P-O-F]) when identifying subjects with and without hip joint osteoarthritis (OA). Muscle performance of the hip abductor muscles was obtained in standing by using the P-O-F position measured with a goniometer and in supine using a handheld dynamometer (HHD) and a manual muscle test (MMT). We studied 20 healthy adults (10 men and 10 women) and 20 adults (10 men and 10 women) with radiographically documented hip joint OA. Indices including sensitivity, specificity, and positive likelihood ratios examined values obtained from the P-O-F position and the MMT when used to identify subjects with and without hip joint OA. Sensitivity of the P-O-F position for identifying subjects with hip joint OA was 0.55, and specificity was 0.70, yielding a positive likelihood ratio of 1.83. Sensitivity of normalized hip abductor MMT strength for identifying subjects with hip joint OA was 0.35 and specificity was 0.90, yielding a positive likelihood ratio of 3.5. Based on validity information from the present study, the Trendelenburg test (P-O-F angle) is not useful in identifying subjects in the early stages of hip joint OA.