Performing region-specific tasks does not improve lower extremity patient-reported outcome scores.

Background: Patient-reported outcome measures quantify outcomes from patients' perspective with validated instruments. QuickDASH (Quick Disability of Arm, Shoulder and Hand, an upper extremity PROM) scores improve after completing instrument tasks, suggesting patient-reported outcome results can be modified. We hypothesized that performing lower extremity tasks on the knee injury and osteoarthritis outcome score for joint reconstruction (KOOS-JR) and hip disability and osteoarthritis outcome score for joint reconstruction (HOOS-JR) instruments would similarly improve the scores.

Methods: Forty seven hip and 62 knee osteoarthritis patients presenting to a suburban academic center outpatient osteoarthritis and joint replacement clinic were enrolled and randomized to an intervention or a control group. Inclusion criteria were age over 18 years and English competency. Patients completed a HOOS-JR or KOOS-JR instrument, completed tasks similar to those of the instrument (intervention) or the QuickDASH (control), and then repeated instruments again. Paired and unpaired t-tests were used to compare the intervention and control group scores before and after tasks.

Results: There was no significant difference in total or individual scores after task completion compared to baseline in either the HOOS-JR or the KOOS-JR groups. There was no significant difference in the scores between the intervention or control groups.

Conclusions: Disability may be less modifiable in the lower extremity than in the upper extremity, perhaps because upper extremity activities are more easily compensated by the contralateral limb, or because lower extremity activities are more frequent. Thorough evaluation of factors influencing patient-reported outcome measures is necessary before their extensive application to quality control and reimbursement models.