Good physical function but reduced quality of life in children 3 years after ACL reconstruction.

PURPOSE: To assess children's physical function and subjective knee status 1 and 3 years after anterior cruciate ligament (ACL) reconstruction. It was hypothesised that there was no difference between the operated and normal legs in relation to physical strength and function, that there was <-2 mm side-to-side difference in knee laxity, and that the subjective knee function was better 3 years after ACL reconstruction compared to 1 year after. METHODS: Children (<16 years of age) who had an ACL reconstruction had follow-up with physical function tests (four hop tests and strength measurement in a power rig [PR]), anterior knee laxity (measured using a Rolimeter) and patient-reported outcome measures (Pedi-International Knee Documentation Committee [IKDC] and Knee injury and Osteoarthritis Outcome Score [KOOS]-Child) 1 and 3 years postoperatively. Changes from 1- to 3-year follow-up were evaluated with a paired t test. RESULTS: Out of 148 ACL reconstructed children, 60 had all measures. The four hop tests and the PR all yielded a Limb Symmetry Index >90% at both follow-ups. There was a significant improvement from 1- to 3-year follow-up in two-hop tests (6 m on time and crossover hop). Side-to-side knee laxity was >2 mm in four children at 1- and 3-year tests. Pedi-IKDC scores increased, and KOOS-Child improved significantly from 1 to 3 years in two of the five domains: 'Sport' and 'Quality of life', but scores were lower than in a cohort of normal children. CONCLUSION: The children had good objective physical function 1 and 3 years after ACL reconstruction. However, scores from the KOOS-Child sport-specific function and quality of life domains were lower than in normal children. LEVEL OF EVIDENCE: Level II.

Similar outcomes after anterior cruciate ligament reconstruction in paediatric and adult populations: a 1-year follow-up of 506 paediatric operations in Denmark.

PURPOSE: To present 1-year results after all paediatric anterior cruciate ligament (ACL) reconstructions in Denmark (5.9 M inhabitants) for the 10½ year period, 1 July 2011 to 31 December 2021. METHODS: All children who had an ACL reconstruction were enrolled. They were asked to complete Pedi-IKDC preoperatively and at 1-year follow-up. Independent observers performed pivot shift test and instrumented laxity assessment preoperatively and at 1-year follow-up. RESULTS: The median age of the 506 children (47.2% girls) was 14.3 years (9.3-15.9). The Pedi-IKDC score increased from preoperatively 61.6 ± 15.8 (mean ± SD) to 85.9 ± 13.0 at 1-year follow-up (p < 0.0001). There were concomitant injuries (to meniscus and/or cartilage) in 49.9%, but these children had preoperative and follow-up Pedi-IKDC scores similar to the scores for children with isolated injury to ACL (n. s.). Instrumented anterior laxity was 4.3 ± 1.4 (mean ± SD) mm preoperatively and 1.4 ± 1.4 mm at follow-up (p < 0.0001). Preoperatively, 3% had no pivot shift whilst this was the case for 68% postoperatively (p < 0.0001). Twenty-five children (5.6%) had 4 mm instrumented laxity or more relative to the unoperated knee at follow-up. Two patients (0.4%) had an operatively treated deep infection, three (0.5%) were operated on for reduced range of motion and two (0.4%) had a revision ACL reconstruction. CONCLUSION: ACL reconstruction resulted in a clinically meaningful increase in Pedi-IKDC, an improved instrumented stability, a reduction in the grade of pivot shift and the complication rate was low at 1-year follow-up. The risk of graft insufficiency at 1-year follow-up was the same as in an adult population. LEVEL OF EVIDENCE: II.

No correlation between performance tests, clinical measurements and data from patient-reported outcome measures (PROM) in children reconstructed for anterior cruciate ligament injury.

PURPOSE: To investigate if patient-reported outcome measures (PROMs), functional tests and clinical measures correlate well in children after reconstruction of the anterior cruciate ligament (ACL). It was hypothesized that these outcomes correlate, so it is sufficient to report only one of them. METHODS: A consecutive group of children (< 16 years old) who had an ACL reconstruction, were prospectively followed and assessed after 1-year with Pedi-IKDC and KOOS-Child, instrumented laxity measurement, range of motion, extension strength and four performance tests. Relations between the different outcomes were calculated by partial correlation coefficient analysis, controlling for gender, age, height, and weight. RESULTS: Outcomes were available for 141 of 163 children. There were only few positive and weak correlations between performance tests and PROM scores and between clinical measurements and PROM scores. There were weak to strong correlations between the scores from Pedi-IKDC and the scores from each of the five domains of KOOS-Child and a weak to moderate correlation between the different domains of KOOS-Child. Similar correlations were found between the different performance tests. CONCLUSION: For children who had their ACL reconstructed there was no clinically important correlation between scores obtained by PROMs, a battery of functional performance tests and instrumented laxity of the knee at 1-year follow-up. This is an argument for always to include and report all three types of outcomes. LEVEL OF EVIDENCE: Level II.

Reference data for hop tests used in pediatric ACL injury rehabilitation: A cross-sectional study of healthy children.

In rehabilitation, four single-leg hop tests are frequently used for evaluation of ACL-injured children. However, reference values on single-leg hop performance and the corresponding limb symmetry indexes (LSIs) of healthy children younger than 15 years of age are lacking. Thus, the purpose was to describe hop performance and LSIs in healthy Danish children, and to quantify the proportion of participants passing LSI values of ≥85% as well as ≥90%. Healthy children aged 9-15 years were invited to participate in the study. Hop performance (single hop, 6-m timed hop, triple hop, and cross-over hop) was assessed for each leg for each hop test and expressed as absolute, normalized (to body height), and LSI values. Descriptive statistics were applied to calculate mean ±SD for all outcomes within age and gender groups. Further, the 95% reference interval was calculated for each age and gender group. A total of 531 healthy children (52% girls) were included in the study, representing seven age groups (9-15 years). The LSI group means across all participants for the four hop tests ranged between 84 and 95%. Between 70 and 83% of the children had an LSI of ≥85%, while 50 to 65% of the children had an LSI of ≥90%. The present reference material can be used in clinical practice when evaluating hop performance in pediatric ACL patients.