Certain shoe insoles do not appear to alleviate osteoarthritis knee pain other than to create a placebo effect, according to a study by researchers at the University of Manchester Institute of Inflammation and Repair.
885 patients with osteoarthritis participated in the study. The individuals were divided into 12 different groups, with each receiving a different type of supportive footwear.
Researchers said the orthotics did have a significant impact compared to the control group, but the impact was mostly contained to studies that used regular shoes without inserts as the control group. When the trials were conducted using a control group with a flat or “neutral” shoe insert, the control group reported no significant difference in pain levels compared to the groups that used lateral wedge shoe insoles.
“This suggests an anticipation bias on the part of subjects who expect a benefit with the intervention compared to no intervention,” said Dr. Marc C. Hochberg, who heads the rheumatology and clinical immunology department at the University of Maryland. “The clinical implications are for healthcare practitioners not to recommend lateral wedge insoles and for patients not to buy them.”
Matthew J. Parkes, a co-author of the study, said he wasn’t surprised that patients experienced a placebo effect during the trial.
“Pain, being a self-reported, subjective outcome, is particularly susceptible to [placebo] effects, and such influences have been documented in reviews of osteoarthritis literature,” the researchers noted.
Dr. Silverman comments
This is a curious study.
Why are there questions like “do inserts work to decrease osteoarthritis knee pain?” Because sometimes foot conditions cause knee, hip, and lower back pain.
If the primary problem is the foot, treatment of the foot condition often makes the patient feel better. For example, if the foot collapses inward, patellofemoral pain can develop. An insert can help alleviate pain in this situation, but using an insert to treat knee pain without a foot condition being the underlying cause is a silly thing to attempt.
Related source: MedPage Today
