Establishing Age- and Sex-Specific Norms for Pediatric Return-to-Sports Physical Performance Testing.

BACKGROUND: Graft tears and contralateral anterior cruciate ligament (ACL) tears are common in pediatric athletes after ACL reconstruction. Use of objective return-to-sports (RTS) criteria, in particular physical performance tests (PPTs), is believed to reduce the incidence of secondary injury; however, pediatric norms for these tests are unknown. PURPOSE: To establish a proof of concept for the creation of age- and sex-based norms for commonly used RTS PPTs in healthy pediatric athletes, allowing the creation of growth curves for clinical referencing. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 100 healthy people who were between the ages of 6 and 18 years and involved in organized sports were enrolled, with even distributions of age and sex. All participants underwent 9 common RTS PPTs: stork test, stork test on Bosu, single-leg squat, single-leg squat on Bosu, clockwise and counterclockwise quadrant hops, single-leg hop for distance, 6-m timed hop, and triple crossover hop for distance. Mean performance across limbs was calculated for each individual. Chronological age, height, weight, sex, and self-reported Pubertal Maturational Observational Scale (PMOS) score were recorded. Univariable and multivariable models were created for each PPT, assessing the importance of the recorded descriptive variables. Quantile regression was used to create growth curves for each PPT. RESULTS: The cohort was 52% female, and the mean ± standard deviation age was 11.7 ± 3.6 years. PMOS was highly correlated with age (r = 0.86) and was excluded from the regressions. In univariable regression, age, height, and weight were strong predictors of performance for all PPTs, whereas sex was a predictor of performance on the single-leg and triple crossover hops for distance (with males outperforming females). Height and weight were excluded from multivariable regression because of multicollinearity with age. Multivariable regression showed predictive patterns for age and sex that were identical to those shown in the univariable analysis. Given ceiling effects, quantile regression for the stork tests was not possible, but quantile regression growth curves were successfully created for the 7 remaining PPTs. CONCLUSION: Chronological age and sex accurately predicted performance on common RTS PPTs in pediatric patients. The growth curves presented herein could assist clinicians with benchmarking pediatric patients postoperatively against a healthy athletic cohort.

Healthy Pediatric Athletes Have Significant Baseline Limb Asymmetries on Common Return-to-Sport Physical Performance Tests.

BACKGROUND: Return to sport (RTS) after anterior cruciate ligament (ACL) reconstruction in children is associated with a much higher risk (∼30%) of subsequent ACL injury than in adults. Most RTS testing protocols use a limb symmetry index (LSI) ≥90% on physical performance tests (PPTs) to assess an athlete's readiness for sport. This assumes that, in a healthy state, the physical performances across both lower extremities are and should be equal. PURPOSE: To determine the prevalence of limb asymmetries >10% in the uninjured pediatric population on common PPTs as well as to explore the relationship between athlete variables, limb preference, and LSI values. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: This study included healthy volunteers (N = 100) evenly distributed between the ages of 6 and 18 years (mean age, 11.7 ± 3.6 years; 52% female). Participants performed 9 common PPTs. For analysis, we developed a composite score for each limb by averaging trials. We then calculated the LSI for each test. Univariable and multivariable linear regression analyses were performed to assess the relationship between athlete variables (age, sex, height, and weight) and LSI for each PPT. RESULTS: Instances of poor baseline limb symmetry (<90% LSI) were common across all PPTs. The single-leg timed hop had the highest percentage of participants, with LSI ≥90% at 73%, while the stork on a Bosu ball had the lowest percentage at 23%. After adjusting for age, female sex showed a significant association with LSI for the stork test (P = .010) and the quadrant hop-counterclockwise (P = .021). Additionally, after adjusting for sex, increasing age showed a significant association with LSI for the stork test (P < .001), single-leg squat on a Bosu ball (P = .010), quadrant hop-clockwise (P = .016), and quadrant hop-counterclockwise (P = .009). CONCLUSION: The majority of healthy athletes 18 years and younger demonstrated significant (<90%) limb asymmetries. Limb symmetry was not consistently affected by participant age or sex, and the effect sizes of these relationships were small. These findings should encourage clinicians and coaches to exercise caution in using the LSI as an isolated measure of RTS readiness after injury in pediatric athletes.

Factors predictive of poorer outcomes in the surgical repair of multiligament knee injuries.

PURPOSE: To investigate the influence of injury and treatment factors on clinical/functional outcomes in multiligament knee injuries (MLKI). METHODS: Thirty-nine consecutive patients with confirmed and surgically treated MLKI who met inclusion criteria were scheduled for a follow-up visit to obtain: SF-12 and subjective feeling of normalcy between the operated and healthy knee, and IKDC, active range of motion (ROM), and stability exam (Lachman test, posterior drawer, and dial test at 30°). A chart review was used to obtain data on injury and treatment factors. RESULTS: The postoperative mean (SD) outcomes were: IKDC score 62.7 (25.9), flexion-extension ROM 125° (29°), and percentage of normalcy 74% (20%). The postoperative normal/nearly normal stability exam was: Lachman test 36 (95%) patients, posterior drawer at 90° 38 (97%) patients, and dial test of 39 (100%) patients. There were 24 (61.5%) and 23 (59%) patients with complications and reoperations, respectively. The presence of bicruciate injuries was associated with worse Lachman (p = 0.03) and posterior drawer tests (p = 0.03). Presence of injury to meniscal structures was associated with worse Lachman test (p = 0.03), lower percentage of normalcy (p = 0.02) and extension lag (p = 0.04). Injury to cartilage structures was associated with worse IKDC scores (p = 0.04). IKDC was lower in cases of posterolateral corner reconstruction (p = 0.03) and use of allograft tendons for reconstruction (p = 0.02); ROM was lower in allograft reconstruction (p = 0.02) and need for meniscal repair (p = 0.01). Bicruciate reconstruction led to worst posterior drawer test (p = 0.006). CONCLUSIONS: The outcomes of MLKI might be negatively influenced by bicruciate ligament, meniscal, and cartilage injuries; with regards to treatment characteristics, need for posterolateral corner or bicruciate ligament reconstruction, use of allografts, or need for meniscal repair may similarly diminish outcomes. While surgical treatment provides good overall function, ROM and stability, it rarely results in a "normal" knee and the chances of complications and reoperations are high. LEVEL OF EVIDENCE: Cross-sectional comparative study, Level III.

Correction to: Factors associated with poorer outcomes in the surgical treatment of multiligament knee injuries.

The author would like to correct the following errors in the publication of the original article.

The validity and reliability of ultrasound on identifying supraspinatus tears during passive external rotation from 0° to 30°: a pilot project.

BACKGROUND: Controversy exists regarding how much external rotation should be allowed following rotator cuff repair. Clinicians may use ultrasound imaging (USI) to visualize the supraspinatus (SSp) tendon during passive external rotation. However, the validity and reliability of USI used to assess supraspinatus tendon gap formation during external rotation needs to be established prior to using this technique in patient cohorts. METHODS: Ten subjects with magnetic resonance imaging (MRI) confirmation of full-thickness SSp tears were matched to 10 control subjects. Images of the SSp were obtained at 0°, 10°, 20° and 30° of external rotation by a blinded tester on two occasions to establish both validity and reliability of the measure. RESULTS: Validity was established as 70% agreement between the USI and MRI confirmed SSp tear group; reliability was established at greater than 0.90 at all positions of external rotation measured. CONCLUSIONS: USI may be used to detect SSp tears with 70% validity, and the technique is reliable in all positions of external rotation.

Bilateral differences in the upper quarter function of high school aged baseball and softball players.

PURPOSE/BACKGROUND: The Upper Quarter Y Balance Test (YBT-UQ) was developed as a way to identify upper extremity and trunk mobility in the open kinetic chain in the reaching limb as well as midrange limitations and asymmetries of upper extremity and core stability in the closed kinetic chain on the stabilizing limb. Performance on the YBT-UQ is similar between genders and between limbs; however, this has not been examined in athletes who participate in sports that result in upper extremity asymmetries. The primary purpose of this study is to determine if differences exist between the throwing vs. non-throwing sides in high-school baseball and softball athletes on the YBT-UQ. METHODS: In order to complete this forty-eight male high school baseball players and seventeen female high school softball players were tested on the YBT-UQ. Reach distances were normalized to arm length (% AL). Comparisons were made between the throwing (T) and non-throwing (NT) arm for each direction as well as the composite score. RESULTS: No significant differences were observed between the T and NT arm for the medial (NT: 98.4 ± 8.6 %AL, T: 99.1 ± 8.6 %AL, p=0.42), inferolateral (NT: 90.8 ± 11.8 %AL, T: 90.3 ± 11.5 %AL, p =0.61), superolateral (NT: 70.6 ± 10.9 %AL, T: 70.4 ± 11.1 % AL, p=0.91) reaches, or the composite score (NT: 87.2 ± 8.9 % AL, T: 86.6 ± 8.1 %AL, p=0.72). Similarly, no differences were observed between the male baseball and female softball players (p=0.30-0.90). CONCLUSIONS: Based on these findings, it was concluded that there was no difference in performance on the YBT-UQ between throwing and non-throwing limbs in high school baseball and softball players. LEVEL OF EVIDENCE: 3.