Purpose. This study evaluated the validity of the Patient Specific Functional Scale (PSFS) in patients with upper extremity nerve injury.
Methods. Following Research Ethics Boards (REB) approval, we included English-speaking adults, with greater than 6 months after an upper extremity nerve injury. Patient reported questionnaires included: PSFS, 36-item short-form health survey (SF-36), Disabilities of the Arm, Shoulder and Hand (DASH), McGill Pain Questionnaire, Pain Catastrophizing Scale (PCS) and Pain Disability Index (PDI). Statistical analyses evaluated the relationships among the outcome measures and the independent variables (age, gender, nerve injured, time since injury, work status, worker’s compensation/litigation). Linear regression was used to evaluate the variables that predicted the PSFS.
Results. There were 157 patients (53 women, 104 men); median time since injury of 14 months. The mean ± SD scores were: PSFS 3.1±2.3, DASH 44±22, PCS 16±15, pain intensity 4.2±3.0, pain rating index 13±11, PDI 28.3±17.6 and SF-36 component scores physical (41.8±8.7) mental (45.9± 12.6). There were moderate correlations between the PSFS and the DASH, and the SF-36 physical role domain. The PSFS was significantly lower in brachial plexus injuries. The final model explained 20.7 % of the variance and independent variables were DASH, nerve injured and age.
Conclusion. This study provides evidence of construct validity of the PSFS for patients with upper extremity nerve injury. The PSFS is a valid method to assess functional limitations identified by the individual and can be completed in a shorter period of time than the DASH.Christine Novak was supported by a Canadian
Institutes of Health Research (CIHR) Doctoral Fellowship Award and
is supported in part through IAMGOLD Fellowship. Joel Katz is
supported by a CIHR Canada Research Chair in Health Psychology
at York University. This research study was supported in part by a
Research Award from the American Association for Hand Surgery