Abstract
Purpose
No knee-specific outcome measures have demonstrated reliability, validity or responsiveness in patients with multiligament knee injuries. Furthermore, the content validity of existing questionnaires has been challenged and remains unknown for patients with concomitant neurovascular injury. As a first step in developing a disease-specific outcome measure, the objective of this study was to identify items from existing knee questionnaires pertinent to patients with multiligament knee injuries using established a priori criteria.
Method
Eighty-five consecutive patients from a level one trauma centre were mailed a questionnaire comprising 124 items from 11 knee-specific instruments. They rated the frequency and importance for each item on a five-point Likert scale. Criteria for item selection included a mean importance rating (MIR) ≥ 3.5 and frequency < 30% for the response never experienced. The World Health Organization International Classification of Functioning, Disability and Health (ICF) framework was used to support the content.
Results
The average age of the 60/85 respondents (70.6%) was 34.7 years and most were male (n=45). Average time from injury was 845 days. Using the Schenck classification, 19 patients were KD I, two were KD II, 39 were KD IIIL or IIIM, and nine were KD IV. Nineteen had peroneal nerve injury and five had a vascular injury. Forty-four patients were treated surgically, six nonoperatively and 10 are pre-operative. Sixty-one of 124 questionnaire items met the a priori inclusion criteria. Based on the ICF, 22 of the retained items were physical impairments (PI), 15 items were emotional impairments (EI), 18 items were activity limitations (AL), and six items were participation restrictions (PR). The 10 items with the highest MIR included six EI, one PI and three PR. Twenty-four items (PI=6 EI=13, AL=2, PR=3) of the Anterior Cruciate Ligament Quality of Life Questionnaire (ACL-QoL) satisfied the a priori criteria and this instrument also endorsed the most items within the EI and PR constructs. The Knee Osteoarthritis and Injury Outcome Score (KOOS) had 21 items (PI=7, EI=2, AL=11, PR=1) which satisfied the a priori criteria and also had the most items within the PI and AL constructs. The International Knee Documentation Committee (IKDC) Subjective Knee Form had 12 items (EI=0, PI=3, AL=9, PR=0) meeting criteria while the remaining questionnaires contained 11 items with concepts redundant to above. Combining the ACL-QoL and KOOS resulted in representation of 41/61 of the retained items (PI=13, EI=13, AL=12, PR=3). No existing instrument includes content that may result from neurological or vascular injury.
Conclusion
This work has identified over sixty pertinent items across the various ICF domains relevant to patients with multiligament knee injuries. The ACL-QoL and KOOS together address over two thirds of these items. Patient and clinician focus groups will be conducted to address missing content and to further refine the questionnaire items.
