Glucocorticoid Not As Effective As Physical Therapy for Osteoarthritis Pain

Gail Deyle, DSc

Physical therapy for patients with knee osteoarthritis led to less pain and functional disability at 1 year than patients who received an intraarticular glucocorticoid injection, according to the findings of a new study.

Gail Deyle, DSc, and colleagues conducted a randomized trial on patients with osteoarthritis of the knee to compare physical therapy with glucocorticoid injection in the primary care setting in the US Military Health System. Physical therapy resulted in less pain and more functional ability at 1 year compared to injection, the team found.

Deyle, a senior faculty member of the Army-Baylor University Doctoral Fellowship in Orthopedic Manual Physical Therapy, and the investigators enrolled 156 patients with a mean age of 56 years. Patients had osteoarthritis in 1 or both knees and were randomly assigned in a 1:1 ratio to either undergo physical therapy or a glucocorticoid injection. All patients were beneficiaries of the Military Health System and were active-duty or retired service members or family.

To be included, patients had to be >38 years old and presented to 1 of 2 large military hospitals from October 2012-May 2017. Patients were excluded if they received an injection or underwent physical therapy for knee pain in the previous 12 months or had no radiographic evidence of osteoarthritis.

For those in the physical therapy group, they received instructions and images for exercises, joint mobilizations, and the clinical reasoning underlying the priorities, dosing, and progression of treatment. During a session, the therapist implemented hands-on, manual techniques before the patient did reinforcing exercises.

The patients had <8 physical therapy sessions over the 4-6-week period. Patients could go to an additional 1-3 sessions at the time of the four-month and nine-month reassessments.

An orthopedist or rheumatologist delivered the intraarticular injections to the patients in the glucocorticoid group. Patients received an injection in 1 or both knees of 1 ml of triamcinolone acetonide and 7 ml of 1% lidocaine. Each patient was reexamined at 4 and 9 months to discuss the continued care plan. The discussion included whether it was appropriate for the patient to have an additional injection. The patients could have <3 injections over the one-year period.

The primary outcome of the study was the total score on the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) at 1 year (scores range from 0-240, higher scores indicated worse pain, function, and stiffness). Additional outcomes included the time needed to complete the Alternate Step Test and the Timed Up and Go test and the Global Rating of Change scale score.

Of the 156 patients enrolled, 78 were assigned to each group. Characteristics including pain severity and disability level were similar among both groups.

The mean baseline WOMAC scores were 108.8±47.1 in the injection group and 107.1±42.4 in the physical therapy group.

After 1 year, the mean scores were 55.8±53.8 for the glucocorticoid group and 37±30.7 in the therapy group (mean between-group difference, 18.8 points; 95% CI, 5-32.6).

Secondary outcome changes were in the same direction as those of the primary outcome. The median score on the Global Rating of Change scale was +5 (quite a bit better) in the physical therapy group and +4 (moderately better) in the injection group.

Physical therapy for knee osteoarthritis led to better pain score improvement and better physical function than glucocorticoid injection at 1 year, the study authors concluded.

The study, “Physical Therapy versus Glucocorticoid Injection for Osteoarthritis of the Knee,” was published online in the New England Journal of Medicine.