The reliability and precision of measurement in sports medicine are of concern in both research and clinical practice. The validity of conclusions drawn from a research project and the rationale for decisions made about the care of an injured athlete are directly related to the precision of measurement. Through analysis of variance, estimates of reliability and precision of measurement can be quantified. The purpose of this manuscript is to introduce the concepts of intraclass correlation as an estimate of reliability and standard error of measurement as an estimate of precision. The need for a standardized set of formulas for intraclass correlation is demonstrated, and it is urged that the standard error of measurement be included when estimates of reliability are reported. In addition, three examples are provided to illustrate important concepts and familiarize the reader with the process of calculating these estimates of reliability and precision of measurement.
Craig R. Denegar and Donald W. Ball
Matthew P. Callahan, Craig R. Denegar and Craig A. Segree
Orthotics are commonly prescribed for the treatment of lower extremity injuries secondary to hyperpronation. However, the efficacy of vacuum-molded orthotics has not been established. We assessed the effects of vacuum-molded orthotics on pain and level of function in athletes suffering from plantar fasciitis, medial tibial stress syndrome, or knee pain secondary to hyperpronation. Fourteen athletes assessed their pain and level of function during athletic activity before being fitted for orthotics (Professional Rx, SuperFeet In-Shoe Systems Inc.) and weekly for 7 weeks following break-in. Five athletes (36%) reported complete pain resolution and eight (57%) reported substantial improvement. Eight athletes (57%) reported full return to athletic participation and five (36%) reported substantial improvement in athletic function. One athlete failed to respond to treatment. Results indicate that vacuum-molded orthotics are an effective treatment for lower extremity overuse injuries secondary to hyperpronation.
Jay Herteil and Craig R. Denegar
Jennifer M. Medina McKeon, Craig R. Denegar and Jay Hertel
The purpose of this study was to formulate a predictive equation to discriminate males from females using static and dynamic lower extremity (LE) alignments. Twenty-four healthy adults volunteered to participate. Three-dimensional motion analysis was used to assess the kinematics of the right hip and knee during two functional tasks. Six measures of static LE alignment were also performed. Statistical comparisons were made between males and females for all variables. Static and dynamic variables that were significantly different by sex were entered into separate discriminant analyses for each task. The resulting equations were each able to correctly predict 87% of the subjects by sex. Fifty-eight percent and 55% of the variance was explained by sex for the vertical jump and plant & jump, respectively. The frontal plane hip angle was the best predictor of sex for both tasks. While there were statistically significant differences between the sexes for static measures of LE alignment, kinematic measures were better at discriminating between sexes.
Michael F. Joseph, Kathryn Taft, Maria Moskwa and Craig R. Denegar
Systematic literature review.
To assess the efficacy of deep friction massage (DFM) in the treatment of tendinopathy.
Anecdotal evidence supports the efficacy of DFM for the treatment of tendinopathy. An advanced understanding of the etiopathogenesis of tendinopathy and the resultant paradigm shift away from an active inflammatory model has taken place since the popularization of the DFM technique by Cyriax for the treatment of “tendinitis.” However, increasing mechanical load to the tendinopathic tissue, as well as reducing molecular cross-linking during the healing process via transverse massage, offers a plausible explanation for observed responses in light of the contemporary understanding of tendinopathy.
The authors surveyed research articles in all languages by searching PubMed, Scopus, Pedro, CINAHL, PsycINFO, and the Cochrane Library using the terms deep friction massage, deep tissue massage, deep transverse massage, Cyriax, soft tissue mobilization, soft tissue mobilisation, cross friction massage, and transverse friction massage. They included 4 randomized comparison trials, 3 at the extensor carpi radialis brevis (ECRB) and 1 supraspinatus outlet tendinopathy; 2 nonrandomized comparison trials, both receiving DFM at the ECRB; and 3 prospective noncomparison trials—supraspinatus, ECRB, and Achilles tendons. Articles meeting inclusion criteria were assessed based on PEDro and Centre for Evidence-Based Medicine rating scales.
Nine studies met the inclusion criteria.
The heterogeneity of dependent measures did not allow for meta-analysis.
The varied locations, study designs, etiopathogenesis, and outcome tools used to examine the efficacy of DFM make a unified conclusion tenuous. There is some evidence of benefit at the elbow in combination with a Mills manipulation, as well as for supraspinatus tendinopathy in the presence of outlet impingement and along with joint mobilization. The examination of DFM as a single modality of treatment in comparison with other methods and control has not been undertaken, so its isolated efficacy has not been established. Excellent anecdotal evidence remains along with a rationale for its use that fits the current understanding of tendinopathy.
Jennifer E. Earl, Jay Hertel and Craig R. Denegar
Dynamic malalignment (DM), abnormal muscle activation, and static malalignments all might lead to patellofemoral pain (PFP) but have not been examined using a multifactorial approach.
To determine which measures of static malalignment, DM, and muscle-onset times best predict PFP.
Design and Setting:
2 groups (PFP and uninjured) of 16 subjects each.
EMG and 3-D kinematic data were recorded during a step-down. Five static-alignment assessments were performed.
Three discriminant analyses using injury as the grouping variable and static measures, joint angles, and EMG onsets as the predictor variables. A final combined discriminant analysis using the most predictive variables from each set.
The static-alignment discriminant function was most predictive (81.3% correct), followed by the kinematic (69%) and the EMG (67%) functions. The final discriminant function included iliotibial-band flexibility, navicular drop, pronation, knee flexion, hip adduction, gluteus medius, and vastus medialis obliquus onset time and correctly classified 92.3% of PFP subjects.
PFP can most accurately be predicted when multiple measures of lower extremity function are considered together.
Susan B. Andersen, Donna M. Terwilliger and Craig R. Denegar
The purpose of this study was to determine if a difference exists in the reproducibility of knee joint flexion angles in an open versus a closed kinetic chain. Thirty generally healthy subjects (12 males, 18 females; mean age 23.8 years) participated. Subjects actively reproduced small, medium, and large knee flexion angles (with target angles of 15°, 45°, and 75°, respectively) in an open and a closed kinetic chain while being videotaped. Goniometric measurements were taken from the videotape of initial and reproduced joint angles. Data were analyzed using ANOVA with repeated measures on kinetic chain test position and joint angle. Subjects more accurately reproduced knee flexion angles in a closed kinetic chain position. The main effect for angle and the interaction of angle and test position were nonsignificant. The results indicate that knee joint position is more accurately reproduced in closed kinetic chain. Closed kinetic chain testing is also a more functional assessment of joint position sense, and thus closed kinetic chain assessment of lower extremity joint position sense is recommended.
Jay Hertel, S. John Miller and Craig R. Denegar
To estimate intratester and intertester reliability and learning effects during the Star Excursion Balance Tests (SEBTs).
A university athletic training research laboratory.
Sixteen healthy volunteers with no history of balance disorders or significant lower extremity joint pathology.
Length of excursion was measured manually for each trial.
ICCs for intratester reliability were .78–.96 on day 1 and 32–.96 on day 2. ICCs for intertester reliability were .35–.84 on day 1 and .81–.93 on day 2. Significant learning effects were identified for 4 of the 8 tests.
Estimates of intratester and intertester reliability were high, but adequate practice trials should be performed before taking baseline measures.
Todd A. Evans, Jennifer R. Kunkle, Krista M. Zinz, Jessica L. Walter and Craig R. Denegar
To assess the efficacy of lidocaine iontophoresis on myofascial trigger-point pain.
University athletic training facility.
Randomized, double-blind, placebo-controlled, repeated-measures.
Twenty-three subjects with sensitive trigger points over the trapezius.
Placebo iontophoresis treatment without current or lidocaine, control treatment using distilled water and normal current dose, medicated treatment using 1% lidocaine and normal current dose.
Main Outcome Measure:
Trigger-point pressure threshold assessed with an algometer.
ANOVA revealed a significant difference among treatments (F 2,40 = 7.38, P < .01). Post hoc comparisons revealed a significant difference in pressure threshold between the lidocaine treatment and the control (P = .01) and placebo (P = .001) treatments. Effect sizes of .28 and .39, respectively, were found for these comparisons.
Although the data revealed significant differences between treatments, the small effect sizes and magnitude of the pressure-sensitivity deviation scores suggest that iontophoresis with 1% lidocaine is ineffective in treating trigger points.