Catherine Quatman-Yates

A 'plane' explanation of anterior cruciate ligament injury mechanisms: a systematic review.

Although intrinsic and extrinsic risk factors for anterior cruciate ligament (ACL) injury have been explored extensively, the factors surrounding the inciting event and the biomechanical mechanisms underlying ACL injury remain elusive. This systematic review summarizes all the relevant data and clarifies the strengths and weaknesses of the literature regarding ACL injury mechanisms. The hypothesis is that most ACL injuries do not occur via solely sagittal, frontal or transverse plane mechanisms. Electronic database literature searches of PubMed MEDLINE (1966–2008), CINAHL (1982–2008) and SportDiscus® (1985–2008) were used for the systematic review to identify any studies in the literature that examined ACL injury mechanisms. Methodological approaches that describe and evaluate ACL injury mechanisms included athlete interviews, arthroscopic studies, clinical imaging and physical exam tests, video analysis, cadaveric studies, laboratory tests (motion analysis, electromyography) and mathematical modelling studies. One hundred and ninety-eight studies associated with ACL injury mechanisms were identified and provided evidence regarding plane of injury, with evidence supporting sagittal, frontal and/or transverse plane mechanisms of injury. Collectively, the studies indicate that it is highly probable that ACL injuries are more likely to occur during multi-planar rather than single-planar mechanisms of injury.

A systematic review of sensorimotor function during adolescence: a developmental stage of increased motor awkwardness?

Background Although adolescent motor awkwardness and increased injury susceptibility have often been speculated and researched, studies regarding adolescent regressions in motor control have yielded inconsistent conclusions. Thus, the relationship between adolescent maturation and injury risk remains unclear. The purpose of this study was to systematically review the literature relative to two questions: (1) Which sensorimotor mechanisms are not fully mature by the time children reach adolescence? and (2) Is adolescence a period when children exhibit delays or regressions in sensorimotor mechanisms? Methods Systematic searches for keywords were performed in February 2010 using PubMed MEDLINE (from 1966), CINAHL (from 1982) and SPORTDiscus (from 1985) databases. Articles were reviewed relative to predetermined criteria, and the methodological quality of each included study was assessed. Results The search identified 2304 studies, of which 33 studies met the inclusion criteria. All 33 identified studies provided results associated with Question 1, 6 of which also yielded results pertaining to Question 2. The search results indicated that many aspects of sensorimotor function continue to mature throughout adolescence, and at least some children experience delays or regressions in at least some sensorimotor mechanisms. The results also exposed several significant weaknesses in our knowledge base. Conclusion The identified knowledge gaps are critical barriers because they hinder methods for identifying children at high risk and diminish the efficacy of targeted prevention programmes. Implications regarding research on adolescent injury risk are discussed and recommendations for future research such as improved methodological designs and integration of non-linear analyses are provided.

The Influence of Quadriceps Strength Asymmetry on Patient-Reported Function at Time of Return to Sport After Anterior Cruciate Ligament Reconstruction

Background: An objective assessment of quadriceps strength after anterior cruciate ligament reconstruction (ACLR) is an important clinical measure to determine readiness to return to sport (RTS). Not all clinicians are equipped with the means to objectively quantify quadriceps strength limb symmetry indices (Q-LSIs) via lower extremity isokinetic dynamometers, as recommended by previous studies. Purpose/Hypothesis: The purpose of this study was to determine whether the International Knee Documentation Committee 2000 Subjective Knee Form (IKDC) score at time of RTS was a predictor of quadriceps strength in a young, athletic population after ACLR. Two hypotheses were tested: (1) Individuals with higher self-reports of function would demonstrate better quadriceps strength of the involved limb than individuals with lower self-reports of function at the time of RTS, and (2) individuals with higher self-reports of function would have normal quadriceps strength limb symmetry. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: At time of RTS, 139 subjects who had undergone ACLR completed the IKDC. In addition, an isometric quadriceps strength test (Biodex dynamometer) was performed on both lower extremities. Peak torques were calculated, as was the Q-LSI, determined by the formula (involved limb peak torque/uninvolved limb peak torque) × 100%. Participants were dichotomized based on IKDC scores: high IKDC (IKDC ≥90) and low IKDC (IKDC <90). Two-way analysis of variance was used to determine the effect of limb (involved vs uninvolved) and group (high vs low IKDC) on isometric quadriceps strength. Chi-square and logistic regression analyses were then performed to determine whether IKDC scores could predict Q-LSI. Results: At time of RTS, a significant correlation between IKDC scores and (1) peak isometric torque (r = 0.282, P < .001) and (2) Q-LSI (r = 0.357, P < .001) was observed. Individuals with IKDC scores ≥90 were 3 times (OR = 3.4; 95% CI, 1.71-6.93) more likely to demonstrate higher Q-LSI (≥90%). An IKDC score ≥94.8 predicted Q-LSI ≥90% with high sensitivity (0.813) and moderate specificity (0.493). Conclusion: Participants with higher IKDC scores demonstrated an increased likelihood of presenting with greater involved limb quadriceps strength and better Q-LSI. Based on the results of this study, a patient-reported outcome measure, such as the IKDC, may be able to serve as a valuable screening tool for the identification of quadriceps strength deficits in this population; however, it should not be considered an accurate surrogate for isokinetic dynamometry. Furthermore, a score of ≥94.8 on the IKDC is likely to indicate that a patient’s quadriceps strength is at an acceptable RTS level.

A longitudinal evaluation of maturational effects on lower extremity strength in female adolescent athletes.

Purpose: Recent studies demonstrate that adolescent growth without corresponding strength adaptations may lead to the development of risk factors for patellofemoral pain and anterior cruciate ligament injuries. Our purpose was to investigate the longitudinal trajectories of lower extremity strength across maturational stages for a cohort of female student athletes. Methods: A nested cohort design was used to identify 39 subjects who had complete knee flexion, knee extension, and hip abduction strength data for 3 test sessions spaced approximately 1 year apart and during which they transitioned from prepubertal to a pubertal status. Results: Knee extension strength increased while hip abduction and hamstrings-to-quadriceps ratio strength decreased from prepubertal to pubertal stages (P < .05). No effects of time with respect to knee flexion strength or nondominant/dominant limb differences were found (P > .05). Conclusion: These data provide support that preadolescence is an optimal time to institute strength training programs aimed toward injury prevention.

Aerobic Exercise for Adolescents With Prolonged Symptoms After Mild Traumatic Brain Injury: An Exploratory Randomized Clinical Trial

Objective: To describe the methodology and report primary outcomes of an exploratory randomized clinical trial (RCT) of aerobic training for management of prolonged symptoms after a mild traumatic brain injury (mTBI) in adolescents. Setting: Outpatient research setting. Participants: Thirty adolescents between the ages of 12 and 17 years who sustained a mTBI and had between 4 and 16 weeks of persistent symptoms. Design: Partially blinded, pilot RCT of subsymptom exacerbation aerobic training compared with a full-body stretching program. Main Measures: The primary outcome was postinjury symptom improvement assessed by the adolescents self-reported Post-Concussion Symptom Inventory (PCSI) repeated for at least 6 weeks of the intervention. Parent-reported PCSI and adherence are also described. Results: Twenty-two percent of eligible participants enrolled in the trial. Repeated-measures analysis of variance via mixed-models analysis demonstrated a significant group × time interaction with self-reported PCSI ratings, indicating a greater rate of improvement in the subsymptom exacerbation aerobic training group than in the full-body stretching group (F = 4.11, P = .044). Adherence to the home exercise programs was lower in the subsymptom exacerbation aerobic training group compared with the full-body stretching group (mean [SD] times per week = 4.42 [1.95] vs 5.85 [1.37], P < .0001) over the duration of the study. Conclusion: Findings from this exploratory RCT suggest subsymptom exacerbation aerobic training is potentially beneficial for adolescents with persistent symptoms after an mTBI. These findings and other recent research support the potential benefit of active rehabilitation programs for adolescents with persistent symptoms after an mTBI. Larger replication studies are needed to verify findings and improve generalizability. Future work should focus on determining the optimal type, timing, and intensity of active rehabilitation programs and characteristics of individuals most likely to benefit.

The Clinical Utility and Diagnostic Performance of MRI for Identification and Classification of Knee Osteochondritis Dissecans

BACKGROUND Magnetic resonance imaging (MRI) is a common clinical tool used to diagnose and monitor the progression and/or healing of osteochondritis dissecans of the knee. The purpose of this study was to systematically review the literature relative to the following questions: (1) Is MRI a valid, sensitive, specific, accurate, and reliable imaging modality to identify knee osteochondritis dissecans compared with arthroscopy? (2) Is MRI a sensitive tool that can be utilized to characterize lesion severity and stability of osteochondritis dissecans fragments in the knee? METHODS A systematic search was performed in December 2010 with use of PubMed MEDLINE (from 1966), CINAHL (from 1982), SPORTDiscus (from 1985), Scopus (from 1996), and EMBASE (from 1974) databases. RESULTS Seven studies, four Level-II and three Level-III investigations, met the specified inclusion criteria. No randomized controlled studies were identified. Because of inconsistencies between imaging techniques and methodological shortcomings of many of the studies, a meta-analysis was not performed. CONCLUSIONS The limited available evidence, methodological inconsistencies in imaging techniques, and lack of standardized grading criteria used in current studies prevent clear conclusions regarding the diagnostic and specific staging equivalency of MRI with arthroscopy. However, available evidence supports the use of MRI to detect the stability or instability of the lesion. Given the benefits of the use of MRI as a noninvasive tool to diagnose, predict lesion progression, and assess clinical outcomes of treatment, there is a pressing need for high-level, systematic, sound, and thorough studies related to the clinical utility of MRI for assessing osteochondritis dissecans of the knee.

Internal consistency and validity of the QuickDASH instrument for upper extremity injuries in older children

Background: The short version of the Disabilities of the Arm, Shoulder and Hand instrument (QuickDASH) has been shown to be a valid, reliable, and responsive measure of upper extremity function in adults. However, the psychometric properties of the QuickDASH for younger patients have not been well established. The purpose of this study was to evaluate the internal consistency and validity of the QuickDASH for use with older children and adolescents. Methods: The QuickDASH and PedsQL instruments were administered to 149 patients grouped into ages 8 to 12 and 13 to 18 years. Results: Item response analysis showed a low SE of measurement (0.06) and a high coefficient &agr; (0.91), suggesting high internal consistency among items. The QuickDASH was found to be a predictor of PedsQL score for both groups (P<0.01). Conclusions: The results indicate that the QuickDASH is a consistent and valid instrument for older children and adolescents with upper extremity pathology. Level of Evidence: III, case series.

Postconcussion Postural Sway Variability Changes in Youth: The Benefit of Structural Variability Analyses

Purpose: The purpose of this study was to evaluate the utility of postural sway variability as a potential assessment to detect altered postural sway in youth with symptoms related to a concussion. Methods: Forty participants (20 who were healthy and 20 who were injured) aged 10 to 16 years were assessed using the Balance Error Scoring System (BESS) and postural sway variability analyses applied to center-of-pressure data captured using a force plate. Results: Significant differences were observed between the 2 groups for postural sway variability metrics but not for the BESS. Specifically, path length was shorter and Sample and Renyi Entropies were more regular for the participants who were injured compared with the participants who were healthy (P < .05). Conclusion: The results of this study indicate that postural sway variability may be a more valid measure than the BESS to detect postconcussion alterations in postural control in young athletes.

A longitudinal examination of postural impairments in children with mild traumatic brain injury: implications for acute testing

Objective: To examine how postural control changes following pediatric mild traumatic brain injury. Setting: Urban pediatric emergency department. Participants: Children 11 to 16 years old who presented within 6 hours of sustaining mild traumatic brain injury. Design: Prospective observational cohort followed for 1 month. Main Measures: Total center of pressure path velocity and path velocity within distinct frequency bands, ranging from moderate to ultralow, were recorded by the Nintendo Wii Balance Board during a 2-legged stance. Measurements were recorded in 2 separate tests with eyes open and closed. The scores of the 2 tests were compared, and a Romberg quotient was computed. Results: Eleven children were followed for 1 month postinjury. The ultralow frequency, which reflects slow postural movements associated with exploring stability boundaries, was lower (p = .02) during the eyes closed stance acutely following injury. The Romberg quotient for this frequency was also significantly lower acutely following injury (p = .007) than at 1 month. Conclusion: Following mild traumatic brain injury, children acutely demonstrate significantly more rigid sway patterns with eyes closed than with eyes open, which were highlighted by the Romberg quotient. The Romberg quotient could allow for accurate identification and tracking of postural instability without requiring knowledge of preinjury balance ability.

Influence of Age on Postconcussive Postural Control Measures and Future Implications for Assessment.

Objective:To examine the influence of age, sex, attention-deficit hyperactivity disorder (ADHD) status, previous history of concussion, and days since injury on postconcussion postural control assessment in adolescents who have suffered a concussion. Design:Prospective cohort study. Setting:Hospital-based outpatient clinic. Participants:Seventy-one participants (42 males; 29 females) with mean age 14.14 ± 2.44. Independent Variables:Age, sex, previous concussion history, ADHD status, total and severity of postconcussion symptoms, and days since injury. Main Outcome Measures:Total Balance Error Scoring System score, path length, center-of-pressure (COP) area, sample entropy, and Romberg quotient. Results:Pearson product–moment correlation coefficients were calculated to test for potential associations between the continuous participant characteristics and the postural control variables. Spearman correlation was used to test the association between symptom severity and the postural control variables. Standard multiple regression was used to model the extent to which participant characteristics accounted for the variance in the postural sway variables. Age was significantly associated with all of the postural sway variables except COP area for the eyes open condition and sample entropy in the anterior–posterior direction for the eyes closed condition. Sex, ADHD status, and previous concussion history did not significantly predict postural control scores. Conclusions:Age significantly influences scores on common postconcussion postural control assessments. Clinical Relevance:This study demonstrates that age is a critical factor that needs to be accounted for to improve the clinical appropriateness and utility of current postconcussion postural control assessments.