In 2002, Moseley et al.6)
reported that arthroscopic debridement was no better than a placebo procedure in patients with ≥K-L 3 (≥moderate loss of joint space) in a placebo-controlled trial. Subsequently, the Arthroscopy Association of North America (AANA) officially announced that a proper arthroscopic procedure can be particularly beneficial to a specific group of osteoarthritic patients7)
. Afterwards, Jackson and Dieterichs2)
reported that arthroscopic debridement could be effective for early osteoarthritis based on the 4-6 years of follow-up results. Aaron et al.27)
observed improvements in 90% of patients with early osteoarthritis, whereas in 25% of the patients with advanced osteoarthritis during the 34 months of follow-up period after arthroscopic debridement. Steadman et al.19)
reviewed the results of joint insufflation and conventional arthroscopic debridement procedures in patients with ≥K-L 3 osteoarthritis for a minimum 2 years of follow-up. Satisfying results were obtained in 71% of patients, indicating that debridement would improve joint function and level of activity. On the other hand, Siparsky et al.28)
reviewed the current literature and concluded that arthroscopic debridement may have some level of utility in knees with low-grade osteoarthritis, but it cannot be a routine treatment for all osteoarthritic patients. Kirkley et al.3)
assessed the efficacy of arthroscopic debridement using a study design that compensates for some shortcomings of a Moseley's study and found that arthroscopic debridement was not advantageous over optimized physical and medical therapy in patients with ≥K-L 2 osteoarthritis. Litchfield et al.4)
performed arthroscopic treatment on the knees with moderate osteoarthritis in a similar method as Steadman and reported that the procedure had no additional benefits over conservative treatment. These studies indicate that arthroscopic debridement is a procedure still surrounded by controversy.
The prevalence of a meniscal tear is high in middle-aged and elderly patients with ≥K-L 3 osteoarthritis and 61% of those with MRI evidence of a meniscal tear do not present with pain29)
. Bhattacharyya et al.30)
reported that MRI showed meniscal tears in 91% of the osteoarthritic patients with ≥45 years of age and 76% of them had no symptoms. Therefore, they concluded that meniscal tears are common in osteoarthritic knees regardless of the presence of symptoms. In addition, the presence of a tear was neither associated with the level of pain nor had a significant influence on the knee function. Therefore, a meniscal tear may not be the cause of knee pain and it is difficult to determine the cause of pain in knees with both osteoarthritis and meniscal tears. In particular, a meniscal tear is not the major cause of pain in most of the cases with K-L 3-4 osteoarthritis. In general, the need for orthopedic surgery is determined based on the symptoms, quality of life assessment, and disabilities, albeit difficult to quantify. However, anatomical and MRI abnormalities are not related to the symptoms of joint disorders and correction of abnormalities does not necessarily result in functional improvement. Therefore, Marx31)
emphasized the need to individualize decision making on surgery for osteoarthritis, although arthroscopic surgery remains appropriate when osteoarthritis is not believed to be the primary cause of knee pain. The prognostic factors include clinical symptoms in the affected joint, mechanical symptoms, duration of morbidity, presence of a meniscal tear, ROM, lower limb alignment, joint space narrowing, age, weight, and smoking. Favorable prognostic factors are listed in .
Favorable Prognostic Factors
The National Institute for Clinical Excellence (NICE) provided updated guidelines for arthroscopic treatment of osteoarthritis in 2007 where the importance of proper patient selection was emphasized because its efficacy is uncertain and the procedure was recommended for the knees with locking associated with intraarticular loose bodies or meniscus tears. According to the 2008 osteoarthritis treatment guidelines set by the American Association of Orthopedic Surgery (AAOS), arthroscopic debridement or lavage is not recommended for patients with primary diagnosis of symptomatic osteoarthritis of the knee (Recommendation 18), whereas the partial meniscectomy or loose body removal can be an option in the knees with mechanical symptoms of a torn meniscus or loose body, such as catching or locking (Recommendation 19)32)
The indications for arthroscopic debridement based on the review of clinical studies on patient selection27
can be summarized as follows: joint effusion, localized joint line tenderness, acute or aggravating mechanical symptoms, such as catching or locking, development or aggravation of symptoms related to a specific injury mechanism, intraarticular loose body confirmed with imaging, and early stage degenerative arthritis without appearance of malalignment, severe joint space narrowing (≤5 mm), and multiple or large-sized osteophytes. Weight-bearing radiographs, medical records, and physical examination results should be thoroughly evaluated. In addition, care should be taken to the fact that MRI has low specificity and high sensitivity for osteoarthritis of the knee. The patient should be fully aware that the goal of arthroscopic treatment is not to cure the disorder but to relieve pain. Arthroscopic treatment can contribute to symptomatic improvement in patients with advanced osteoarthritis if severe acute pain related to catching or locking occurs in the affected compartment, symptoms related to meniscal tear, loose body, or an articular cartilage flap exist in an intact compartment, or patellofemoral impingement, loss of extension, bursitis, synovitis, intraarticular ligament damage, which is caused by a large-sized osteophyte is present.