Characterization and variability of PROMIS-10 scores with physical therapy in knee osteoarthritis: A retrospective review.

Background: Knee osteoarthritis (OA) and its impairments affect patients' physical and mental health. Radiographically severe knee OA is believed to respond less to conservative treatments including physical therapy (PT) but has not been compared specifically with Patient-Reported Outcomes Measurement Information System (PROMIS)-10.

Objective: To correlate baseline PROMIS-10 physical and mental health scores in patients undergoing PT for knee OA, subgrouped by radiographic severity (Kellgren-Lawrence [KL] grade and number of knee compartments involved). Additionally, to describe the relationship between radiographic severity of knee OA and the change in PROMIS-10 scores post-PT.

Design: Retrospective review.

Setting: Outpatient musculoskeletal clinics at an orthopedic specialty hospital.

Patients (or participants): One hundred nine patients (age ≥ 18 years) who presented for evaluation of knee OA from April 1, 2019 to August 1, 2021, had baseline radiographs, underwent PT, and completed PROMIS-10 at baseline and follow-up.

Interventions: PT.

Main outcome measure(s): PROMIS-10 physical and mental health scores.

Results: Participants were 60% female; average age was 66.6 ± 10.0 years. Baseline PROMIS-10 physical and mental health scores averaged 44.4 ± 7.2 and 52.8 ± 9.0. Post-PT PROMIS-10 physical and mental health scores averaged 44.7 ± 6.7 and 52.6 ± 8.7. Physical health scores improved in 39% of patients; mental health scores improved in 36% of patients (no statistical significance). There was no relationship between post-PT PROMIS-10 scores and radiographic severity of knee OA. Females exhibited osteoarthritic changes in all compartments in 72% of cases compared to 55% of males (p = .020). Females demonstrated a higher predisposition for lateral compartment involvement (83% vs. 64%; p = .021) and a higher proportion of severe OA, radiographically, with a KL grade 3-4 (92% vs. 80%; p = .051).

Conclusions: More than one third of patients with knee OA reported improved physical and mental health post-PT. The degree of benefit did not relate to radiographic severity. Although OA is characterized by radiographic measurements, there are variables beyond the radiographic imaging that may affect patient outcomes.