Physical therapy vs internet-based exercise training for patients with knee osteoarthritis: results of a randomized controlled trial.

OBJECTIVE: To compare the effectiveness of physical therapy (PT, evidence-based approach) and internet-based exercise training (IBET), each vs a wait list (WL) control, among individuals with knee osteoarthritis (OA). DESIGN: Randomized controlled trial of 350 participants with symptomatic knee OA, allocated to standard PT, IBET and WL control in a 2:2:1 ratio, respectively. The PT group received up to eight individual visits within 4 months. The IBET program provided tailored exercises, video demonstrations, and guidance on progression. The primary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC, range 0 [no problems]-96 [extreme problems]), assessed at baseline, 4 months (primary time point) and 12 months. General linear mixed effects modeling compared changes in WOMAC among study groups, with superiority hypotheses testing differences between each intervention group and WL and non-inferiority hypotheses comparing IBET with PT. RESULTS: At 4-months, improvements in WOMAC score did not differ significantly for either the IBET or PT group compared with WL (IBET: -2.70, 95% Confidence Interval (CI) = -6.24, 0.85, P = 0.14; PT: -3.36, 95% (CI) = -6.84, 0.12, P = 0.06). Similarly, at 12-months mean differences compared to WL were not statistically significant for either group (IBET: -2.63, 95% CI = -6.37, 1.11, P = 0.17; PT: -1.59, 95% CI = -5.26, 2.08, P = 0.39). IBET was non-inferior to PT at both time points. CONCLUSIONS: Improvements in WOMAC score following IBET and PT did not differ significantly from the WL group. Additional research is needed to examine strategies for maximizing benefits of exercise-based interventions for patients with knee OA. TRIAL REGISTRATION: NCT02312713.

Q-angle influences on the variability of lower extremity coordination during running.

UNLABELLED: The quadriceps angle (Q-angle) has received attention as a possible predictor of patellofemoral pain (PFP). It has been suggested that an excessive Q-angle alters the patellofemoral tracking, thereby leading to PFP. Traditional methods used to evaluate alterations in lower extremity angular kinematics have not confirmed this thought. A dynamical systems approach involving segment couplings may provide additional insight by addressing the variability of the intersegmental coordination. METHODS: Thirty-two healthy pain-free subjects with varying Q-angles were examined and divided into groups based on gender and Q-angle. Subjects ran overground for 10 trials while three-dimensional kinematic data were collected from the thigh, leg, and foot. The kinematic data were digitized and filtered before a direct linear transformation was employed to calculate three-dimensional segment angles and angular velocities. The variability of the continuous relative phase (CRP) of segment couplings was used to assess between-trial consistency at specific stance phase intervals. RESULTS: No differences in CRP variability were found among subjects with varying Q-angles. Significant differences were present between the specific intervals of the couplings with the greatest variability during initial stance (P < 0.05). CONCLUSIONS: A difference in CRP variability does not appear to exist in the lower extremity between individuals with and without abnormal Q-angles. The significant differences among the stance phase intervals of running suggest the inherent presence of coordination pattern variability. The importance of the increased pattern variability during initial stance may be associated with maintaining external stability.

A dynamical systems approach to lower extremity running injuries.

UNLABELLED: In this paper, we are presenting an alternative approach to the investigation of lower extremity coupling referred to as a dynamical systems approach. In this approach, we calculate the phase angle of each segment and joint angle. Pairing the key segment/joint motions, we use phase angles to determine the continuous relative phase and the variability of the continuous relative phase. Data from two studies illustrate the efficacy of the dynamical systems approach. Individuals who were asymptomatic, even though they may have anatomical aberrant structural problems (i.e. high Q-angle vs low Q-angle) showed no differences in the pattern of the continuous relative phase or in the variability of the continuous phase. However, differences in the variability of the continuous relative phase were apparent in comparing individuals who were symptomatic with patellofemoral pain with non-injured individuals. Patellofemoral pain individuals showed less variability in the continuous relative phase of the lower extremity couplings than did the healthy subjects. We hypothesize that the lower variability of the couplings in the symptomatic individuals indicates repeatable joint actions within a very narrow range. RELEVANCE: We claim that the traditional view of the variability of disordered movement is not tenable and suggest that there is a functional role for variability in lower extremity segment coupling during locomotion. While the methods described in this paper cannot determine a cause of the injury, they may be useful in the detection and treatment of running injuries.

Reliability of the Lido Linea closed kinetic chain isokinetic dynamometer.

Due to increasing emphasis on closed kinetic chain exercises in rehabilitation, there is a need to objectively quantify their effectiveness. The purpose of this study was to determine the test-retest reliability of the peak force and total work scores during a concentric isokinetic leg press pattern using the Lido Linea closed kinetic chain isokinetic dynamometer. The static calibration of force measurements was established by hanging a series of certified weights from a lever arm of known length affixed to the system's force measurement shafts. A repeated-trials, multiple-day experimental paradigm was utilized to establish the static calibration procedure's reliability. No significant difference was found between expected and observed force scores (p > .05). Thirty healthy, active subjects (22.5 +/- 3.9 years) performed concentric isokinetic leg press exercise under maximal voluntary conditions across a velocity spectrum of 25.4, 50.8, and 76.2 cm/sec (10, 20, and 30 inch/sec) in a test-retest experimental paradigm, separated by 24-72 hours. Intraclass correlation coefficient values (ICC 2,1) across Day 1 and Day 2 for peak force and total work ranged from 0.87 to 0.94 (p < .05). The data indicate that the Lido Linea closed kinetic chain isokinetic dynamometer is an appropriate instrument for assessing concentric isokinetic performance during a closed kinetic chain leg press pattern.

Influence of Q-angle on lower-extremity running kinematics.

STUDY DESIGN: Two-group posttest-only comparison. OBJECTIVE: To assess the influence of the Q-angle on the 3-dimensional lower-extremity kinematics during running. BACKGROUND: An excessive Q-angle has been implicated in the development of knee injuries by altering the lower-extremity locomotion kinematics. Previous investigations using 2-dimensional analyses during walking did not support this hypothesis. METHODS AND MEASURES: We hypothesized that individuals with Q-angles more than 15 degrees would display an increase in rearfoot eversion and tibial internal rotation during running. Thirty-two nonimpaired subjects (men: n = 16, mean age = 22 +/- 3 years; women: n = 16, mean age = 23 +/- 3 years) ran over ground, and 3-dimensional kinematic data were collected from the right lower extremity. Subjects with a Q-angle of 15 degrees or less comprised the low-Q-angle group, whereas those with Q-angles of more than 15 degrees comprised the high-Q-angle group. Segment and joint maximum angles and the times when the maxima occurred during stance were measured. RESULTS: The Q-angle magnitude did not increase the maximum segment or joint angles during running. The groups displayed similar maximum angles for rearfoot eversion (low Q-angle, -15.5 +/- 5.0 degrees; high Q-angle, -15.6 +/- 6.6 degrees) and tibial internal rotation (low Q-angle, -8.8 +/- 4.8 degrees; high Q-angle, -6.8 +/- 5.1 degrees). The high-Q-angle group (39.5 +/- 16.3%) achieved maximum tibial internal rotation later in the stance phase than the low-Q-angle group (28.8 +/- 10.7%). CONCLUSIONS: In support of the previous investigations involving Q-angle influences on kinematics, our study did not reveal any differences between groups in maximum joint or segment angles. The kinematic information did reveal that the high-Q-angle group displayed an increase in time to maximum tibial internal rotation. The impact of this single factor on producing knee injury is unknown.

The effects of isokinetic vs. plyometric training on the shoulder internal rotators.

Plyometric training has become a popular training and rehabilitation tool. The purpose of this study was to compare the effects of plyometric and isokinetic concentric/eccentric training of the shoulder internal rotators. Female subjects (N = 78) were randomly assigned to three groups: control, isokinetic training, and plyometric training. Pre-/posttesting measurements included: 1) concentric/eccentric isokinetic power measurements of the shoulder internal rotators at 60 degrees/sec, 180 degrees/sec, and 240 degrees/sec; 2) kinesthetic measurements of shoulder internal rotation, external rotation < 45 degrees, and external rotation > 45 degrees; and 3) a softball distance test. Both groups trained twice a week for 8 weeks. Power and kinesthetic data were analyzed using multiple analyses of variance with repeated measures. A one-way analysis of variance was performed on the softball throw data. No significant (p < .05) pre-/posttest differences were found with kinesthetic testing or the softball throw. Pre-/postpower differences were significantly greater for the isokinetic group at 60 degrees/sec eccentric, 120 degrees/sec concentric and eccentric, and 240 degrees/sec concentric and eccentric. Isokinetic training of the shoulder internal rotators increases isokinetic power, but neither isokinetic nor plyometric training resulted in a functional improvement with the softball throw.