◊ BACKGROUND:
The efficacy of arthroscopic surgery for the treatment of osteoarthritis of the knee is unknown.

◊ METHODS:
We conducted a single-center, randomized, controlled trial of arthroscopic surgery in patients with moderate-to-severe osteoarthritis of the knee. Patients were randomly assigned to surgical lavage and arthroscopic debridement together with optimized physical and medical therapy or to treatment with physical and medical therapy alone. The primary outcome was the total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (range, 0 to 2400; higher scores indicate more severe symptoms) at 2 years of follow-up. Secondary outcomes included the Short Form-36 (SF-36) Physical Component Summary score (range, 0 to 100; higher scores indicate better quality of life).

◊ RESULTS:
Of the 92 patients assigned to surgery, 6 did not undergo surgery. Of the 86 patients assigned to control treatment, all received only physical and medical therapy. After 2 years, the mean (+/-SD) WOMAC score for the surgery group was 874+/-624, as compared with 897+/-583 for the control group (absolute difference [surgery-group score minus control-group score], -23+/-605; 95% confidence interval [CI], -208 to 161; P=0.22 after adjustment for baseline score and grade of severity). The SF-36 Physical Component Summary scores were 37.0+/-11.4 and 37.2+/-10.6, respectively (absolute difference, -0.2+/-11.1; 95% CI, -3.6 to 3.2; P=0.93). Analyses of WOMAC scores at interim visits and other secondary outcomes also failed to show superiority of surgery.

◊ CONCLUSIONS:
Arthroscopic surgery for osteoarthritis of the knee provides no additional benefit to optimized physical and medical therapy. (ClinicalTrials.gov number, NCT00158431.)

◊ Reviewed by L. Bertini
Italy

Osteoarthritis (OA) of the knee is a degenerative disease that causes joint pain, stiffness, and decreased function. Treatment is multidisciplinary and involves physical therapy, medication, and surgery. There are many modalities by which to treat OA, one of which is arthroscopy. Arthroscopic surgery, during which an arthroscope is inserted into the knee joint, allows for lavage, a procedure that removes particulate material such as cartilage fragments and calcium crystals. It also allows for débridement, whereby articular surfaces and osteophytes can be surgically smoothed. The goal of this procedure is to reduce synovitis and eliminate mechanical interference with joint motion.

Unfortunately, there is insufficient evidence to support or to advice against the use of arthroscopic treatment of OA of the knee[1,2]. Despite the lack of consensus guidelines and randomized controlled trials, the use of arthroscopy for the treatment of OA of the knee has increased over the last decade. Techniques used for the arthroscopic treatment of OA of the knee include joint lavage, joint débridement, meniscectomy, abrasion arthroplasty, and microfracture[3]. In a recently published systematic review, authors concluded that studies of arthroscopy as a treatment method for OA of the knee are not conclusive. One reason is that a myriad of different outcome measures are utilised. Therefore, better assessments of postsurgical functional status must be found to more thoroughly evaluate success versus failure of this procedure. To achieve results of utmost clinical relevance, investigators must address and compare the large number of surgical and non-surgical treatment options available to clinicians. Another difficulty in comparing various studies comes from different OA grading systems. Investigations using an arthroscopic grading system for knee OA are prognostically useful for counselling patients on the expected outcome of surgical intervention. Arthroscopic débridement of meniscus tears and knees with low-grade OA may have some utility, but it should not be used as a routine treatment for all patients with knee OA. In a Cochrane review of 2008, the authors concluded that arthroscopic debridement has no benefit for undiscriminated knee OA [4].

In this context the reviewed paper is in line with previous publications. The study design is good, methodologically rigorous, with a sufficient number of enrolled patients. However, it is interesting to note that all patients received general anaesthesia and arthroscopic surgery was performed with tourniquet. In Europe, this has become an obsolete technique and I think that general anaesthesia for arthroscopic surgery is no longer performed in the majority of European hospitals. There are a lot of alternative regional techniques such as intraarticular, peripheral nerve blocks or selective spinal anaesthesia that are safer and more effective for this kind of surgery as was demonstrated in a huge number of studies [5,6,7].Probably this comment is most interesting for anaesthesiologists. However, for those who are involved in chronic pain management it may cause concern that conservative techniques as compared to surgery attain the same results in managing knee pain.

[1] Forster MC, Straw R.
A prospective randomised trial comparing intra-articular Hyalgan injection and arthroscopic washout for knee osteoarthritis. Knee. 2003;10:291-293.

[2] Jackson RW, Dieterichs C.
The results of arthroscopic lavage and debridement of osteoarthritic knees based on the severity of degeneration: a 4- to 6-year symptomatic follow-up. Arthroscopy. 2003;19:13-20.

[3] Stuart MJ, Lubowitz JH.
What, if any, are the indications for arthroscopic debridement of the osteoarthritic knee? Arthroscopy. 2006;22:238-239.

[4] W Laupattarakasem, M Laopaiboon, P Laupattarakasem, C Sumananont
Arthroscopic debridement for knee osteoarthritis. Cochrane Database Syst Rev. 2008 Jan 23;(1):CD0051118

[5] Buckenmaier CC 3rd, Bleckner LL
Anaesthesia for outpatient knee surgery..Best Pract Res Clin Anaesthesiol. 2002 Jun;16(2):255-70.

[6] Sell A, Tein T, Pitkänen M.
Spinal 2-chloroprocaine: effective dose for ambulatory surgery. Acta Anaesthesiol Scand. 2008 May;52(5):695-9.

[7] O'Donnell BD, Iohom G.
Regional anesthesia techniques for ambulatory orthopedic surgery. Curr Opin Anaesthesiol. 2008 Dec;21(6):723-8