Arthroscopic Management of Moderate-to-Severe Osteoarthritis of the Knee: A Systematic Review.

Background: Total knee arthroplasty (TKA) is the procedure of choice for osteoarthritis of the knee (OAK) when conservative treatment fails; however, high rates of dissatisfaction and poor implant longevity dissuade younger patients from TKA. There is a paucity of evidence that report outcomes and clinical effectiveness of arthroscopic knee procedures in patients with end-stage (grade 3-4) OAK. The purpose of this systematic review was to evaluate the efficacy of arthroscopic treatment for patients with moderate-to-severe (grade 3-4) OAK.

Methods: A systematic review of the literature was performed with the terms "Knee," "Osteoarthritis," and/or "Arthroscopic debridement," "Arthroscopic lavage," "Arthroscopic microfracture," "Arthroscopic chondroplasty," "debridement," "lavage," "chondroplasty," "microfracture," and/or "arthroscopy" in PubMed (MEDLINE), Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) databases in November 2023 according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Databases were searched for studies that evaluated outcomes (e.g., pain, function, and conversion to TKA) for patients with Kellgren-Lawrence grade 3 to 4 OAK after knee arthroscopy (including debridement, lavage, microfracture, or chondroplasty) at a minimum 6-month follow-up. Percent improvement from preoperative score was the primary outcome measure. Secondary outcome measures included achievement of minimal clinically importance difference and conversion to TKA.

Results: Nine studies (410 knees with grades 3-4 OAK) were included. Arthroscopic debridement and lavage resulted in a 18.8% to 53.1% improvement at short-term follow-up (e.g., 6 months to 3 years) and a 50.0% improvement at long-term follow-up (e.g., 10 years) in knees with grade 3 OAK and a 15.0% to 41.3% improvement at short-term follow-up and a 46.9% improvement at long-term follow-up in knees with grade 4 OAK. Arthroscopic debridement and microfracture resulted in 1.6% to 50.8% improvement at short-term follow-up in knees with grade 3 OAK. No studies included long-term outcomes or evaluated knees with grade 4 OAK after arthroscopic debridement and microfracture. Conversion to TKA after arthroscopic debridement and lavage occurred in 21.9% of patients with grade 3 OAK and in 35.0% of patients with grade 4 OAK at short-term follow-up and in 47.4% of patients with grade 3 OAK and in 76.5% of patients with grade 4 OAK at long-term follow-up. Conversion to TKA after arthroscopic debridement and microfracture occurred in 10.9% of patients with grade 3 and 4 OAK at long-term follow-up.

Conclusion: Arthroscopic debridement, lavage, and microfracture can provide short- and long-term symptomatic relief and improvement in function by up to 50.0% in patients with grade 3 to 4 OAK. These procedures may result in fewer patients with grade 3 OAK undergoing TKA compared with patients with grade 4 OAK.

Level of evidence: Level IV; systematic review of Level II-IV studies. See Instructions for Authors for a complete description of levels of evidence.