4.1. Participants
chronic pain, osteoarthritis, OA, pain
CHRONIC PAIN, OSTEOARTHRITIS
Knee OA patients were recruited from the Department of Rehabilitation and Functional Recovery of the Humanitas Research Hospital, Rozzano, Milan, Italy from January 2021 to March 2022.An experienced rehabilitation physician screened the patients for eligibility by evaluating the following inclusion criteria: (1) symptomatic unilateral knee with history of chronic pain (at least 3 months) and resistant to at least 1 attempt at conservative treatment (e.g., physical therapy, analgesics); (2) pain score measured with the WOMAC LK 3.1 subscale between ≥9 and ≤19; (3) X-ray imaging findings of osteoarthritis (Kellgren–Lawrence score of 2–3).Exclusion criteria were: (1) age younger than 18 years and older than 80 years; (2) BMI greater than 40 kg/m