Patients with osteoarthritis of the knee who undergo arthroscopic meniscectomy have better outcomes at 6 weeks' follow-up if they receive a steroid injection in the knee joint after surgery, according to the results of a randomized, controlled trial.
The meniscectomy patients who received an intra-articular steroid/lidocaine injection reported significantly less pain and better function at 6 weeks' follow-up than did patients who received a saline/lidocaine injection, sinvestigators reported.
The difference between groups disappeared by 6 months after the operation, however.
The study cohort consisted of 58 patients (59 knees) with a meniscal tear who were treated with arthroscopic surgery at Rush University Medical Center, Chicago, between December 2004 and January 2007. All patients had confirmed chondromalacia (modified Outerbridge grade 2 or higher) in the ipsilateral knee. Exclusion criteria included a steroid injection in the 2 months prior to surgery and inadequate follow-up data. A single surgeon performed all the operations.
Before surgery, patients were randomized in a double-blinded manner to receive a postoperative injection of lidocaine plus either 1 mL (40 mg) of methylprednisolone (Depo-Medrol) or 1 mL of 0.9% normal saline. The injection was administered into the knee after the arthroscopic portals were closed.
The steroid group (19 men, 10 women) had a mean age of 49 years, and the saline group (22 men, 8 women) had a mean age of 52 years.
Before surgery and at follow-up times of 6 weeks and 6, 9, and 12 months, patients had an exam and completed a subjective function survey. The investigators calculated function scores using several systems, including the Knee Injury and Osteoarthritis Outcome Score (KOOS), Lysholm score, International Knee Documentation Committee (IKDC) score, and Short Form-12. There were no significant differences in preoperative scores between groups.
At 6 weeks' follow-up, the steroid group had significantly better scores than did the saline group on the KOOS sport scale, KOOS qQuality of life scale, and IKDC and treatment satisfaction scales, according to the investigators, led by Dr. Loukas Koyonos (Am. J. Sports Med. 2009;37:1077–82).
At 6, 9, and 12 months, “score differences between the steroid and saline groups had disappeared,” the investigators wrote. At these time points, both groups showed significant improvements over their preoperative scores on all scales except the SF-12. By 12 months' follow-up, 86% of the steroid group and 69% of the saline group were “completely or mostly satisfied” with the surgery.
“The addition of a postoperative corticosteroid injection resulted in improved pain and function at an early time point; however, it provided no lasting difference compared with only local anesthetic injection,” the researchers concluded. Additional trials “are necessary to further characterize the benefits, indications, and durability of intra-articular corticosteroid injections” in the setting of OA.
Limitations included the fact that “the study was underpowered to detect a significant difference in the distribution of chondromalacia and meniscectomies,” they wrote.
In addition, “the saline group had a higher prevalence of tricompartmental arthritis and bilateral meniscectomies, suggestive of a more advanced disease state, which may contribute to the lower scores observed in these patients.”
The authors reported that this research was supported by a grant from Pfizer Inc.