Background: Isolated avulsion fractures of the posterolateral structures (the popliteus tendon, the lateral collateral ligament, and the popliteofibular ligament) of the knee are rare.
Purpose: To describe the outcome after an isolated avulsion fracture at the femoral attachment of the posterolateral structures in skeletally immature patients and to communicate our clinical experience concerning diagnosis and treatment.
Study Design: Case series; Level of evidence, 4.
Methods: Six skeletally immature patients (mean age, 13.3 years; range, 12.6-13.7 years; 5 boys, 1 girl) with an avulsion fracture of the femoral attachment of the posterolateral structures were evaluated on average 5.1 years (range, 2.7-8.3 years) after the injury. Five patients were treated with open reduction and fixation of the fragment. The sixth patient was treated nonoperatively with cast immobilization. The evaluation was based on reassessment of radiographs and magnetic resonance imaging (MRI scans), registration of activity level, and examination of objective and subjective knee function.
Results: The injury involved both the popliteus tendon and the lateral collateral ligament in 5 of the 6 cases. In the operated patients, the mean Lysholm knee score was 98 (range, 94-100) (0-100, with higher scores indicating a better outcome). The mean Knee injury and Osteoarthritis Outcome Score (KOOS) quality of life (QOL) was 80 (range, 50-100) (0-100, with higher scores indicating a better outcome). The range of motion and the KT-1000 arthrometer anterior laxity measurements were normal. The nonoperatively treated patient with involvement of both the popliteus tendon and the lateral collateral ligament suffered a bone bridge in the periphery of the femoral physis, causing a valgus deformity of the knee. An open wedge femoral osteotomy was performed. The Lysholm knee score was 80, and KOOS QOL was 25 at follow-up. The patient also had an extension deficit of 5° and a flexion deficit of 10°.
Conclusion: An avulsion of the femoral attachment of the posterolateral structures in skeletally immature patients may involve both the popliteus tendon and the lateral collateral ligament. Open reduction and fixation of the fragment gave a satisfactory outcome.
Background: The International Knee Documentation Committee (IKDC) Subjective Knee Form is a knee-specific measure of symptoms, function, and sports activity. A modified IKDC Subjective Knee Form (pedi-IKDC) has been developed for use in children and adolescents. The purpose of this study was to determine the psychometric characteristics of the pedi-IKDC in children and adolescents with knee disorders.
Hypothesis: The pedi-IKDC is a reliable, valid, and responsive patient-administered outcome instrument in the pediatric population with knee disorders.
Study Design: Cohort study (diagnosis); Level of evidence, 2.
Methods: Test-retest reliability, content validity, criterion validity, construct validity, and responsiveness to change were determined for the pedi-IKDC in patients aged 10 to 18 years with a variety of knee disorders. Test-retest reliability was measured in a group of 72 patients with a stable knee disorder. Validity was measured in a group of 589 patients with the Child Health Questionnaire to determine criterion validity. Responsiveness was measured in a group of 98 patients undergoing a variety of knee surgical procedures.
Results: The overall pedi-IKDC had acceptable test-retest reliability (intraclass correlation coefficient, .91) and excellent internal consistency (Cronbach alpha, .91). The form also demonstrated acceptable floor (0%) and ceiling (6%) effects. There was acceptable criterion validity with significant (P < .01) correlation between the overall pedi-IKDC and 9 relevant domains of the Child Health Questionnaire. Construct validity was acceptable, with all 11 hypotheses demonstrating significance (P < .0001). Responsiveness to change was acceptable (effect size, 1.39; standardized response mean, 1.35).
Conclusion: The pedi-IKDC demonstrated overall acceptable psychometric performance for outcome assessment of children and adolescents with various disorders of the knee.
Background: The International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form (IKDC Knee Form) is a valid, reliable, and responsive measure of knee-related symptoms, function, and sports activities in adults. Despite the incidence of knee injuries in younger individuals, the measurement characteristics of the IKDC Knee Form have not been established.
Hypothesis/Purpose: The purpose of this study was to investigate the validity and internal consistency of the IKDC Knee Form in pediatric, adolescent, and young adult patients with a variety of knee conditions. The authors hypothesized that the IKDC Knee Form would be a valid and consistent measure of knee function in these age groups.
Study Design: Cohort study (diagnosis); Level of evidence, 2.
Methods: The IKDC Knee Form and Pediatric Quality of Life Inventory 4.0 Generic Core Scales (PedsQL) physical functioning component were administered to 673 individuals between 6 and 18 years of age. The internal consistency and validity of the IKDC Knee Form were determined for the entire cohort and for age group cohorts (pediatric, 6-12 years; adolescent, 13-15 years; young adult, 16-18 years) using the PedsQL physical functioning component for comparison.
Results: The results were similar across all age groups. In the original format, internal consistency was high and factor analysis showed a single, dominant component underlying the item responses for each age group. Items 2, 3, and 6 may contribute to measurement error in young individuals. Correlation between the IKDC Knee Form and PedsQL physical functioning component score was moderately high for the entire cohort (r = .83) and for all age groups (pediatric, r = .84; adolescent, r = .84; young adult, r = .79).
Conclusion: In its current form, the IKDC Knee Form is a valid and consistent knee-specific measure of symptoms, function, and sports activity in individuals between the ages of 6 and 18 years with a variety of knee problems. Further work is needed to establish the reliability and responsiveness of the IKDC Knee Form for this age group.
