Arthroscopic washout of the knee: A procedure in decline

Abstract

Background

Osteoarthritis (OA) of the knee is a chronic, progressive condition which often requires surgical intervention. The evidence for the benefits of arthroscopic debridement or washout for knee OA is weak and arthroscopy is currently only indicated in the UK if there is a history of mechanical locking of the knee.

Objectives

To investigate whether there has been any change in the number of arthroscopies performed in the UK since the 2007 NICE guidance on knee arthroscopy and the 2008 Cochrane review of arthroscopic debridement for OA of the knee.

Methods

We interrogated data from the Hospital Episodes Statistics (HES) database with Office of Population Censuses and Surveys-4 (OPSC-4) codes pertaining to therapeutic endoscopic operations in the 60–74 year old and 75 and over age groups.

Results

The number of arthroscopic knee interventions in the UK decreased overall from 2000 to 2012, with arthroscopic irrigations decreasing the most by 39.6 per 100,000 population (80%). However, the number of arthroscopic meniscal resections increased by 105.3 per 100,000 (230%) population. These trends were mirrored in both the 60–74 and 75 and over age groups.

Conclusions

Knee arthroscopy in the 60–74 and 75 and over age groups appears to be decreasing but there is still a large and increasing number of arthroscopic meniscal resections being performed.

Introduction

Osteoarthritis (OA) is the most common form of arthritis and one of the leading causes of disability worldwide [1]. It is a chronic condition characterised by pain, stiffness and reduced function. Pathologically, there is involvement of all joint structures but the key features of OA are a reduction in articular cartilage synthesis with an increase in cartilage degradation [2] together with changes in the subchondral bone [3]. There is no single risk factor for the development of OA. It is a complex, multifactorial disease that occurs as a result of genetic predisposition [4], obesity [5], ageing [6] and excessive joint loading [7], [8], [9]. Epidemiologically, there is a strong female preponderance [10] and there is some difference in the prevalence between racial groups depending on the joint in question [11]. Although there are no recent estimates of the prevalence of OA, it may be as high as 8.5 million in the UK population [12]. Initial treatment currently focuses on conservative measures including analgesia with non-steroidal anti-inflammatory drugs (NSAIDs) and local muscle-strengthening exercise [1]. However due to the progressive nature of OA, these initial measures eventually become ineffective for most patients, in terms of pain control, functionality and overall quality of life.

Arthroscopic washout for knee OA is thought to offer short-term symptomatic relief by reducing the inflammatory response mounted against debris, such as articular cartilage fragments and crystals, which accumulate in the synovial cavity [13], [14]. Arthroscopic debridement is similarly thought to offer short-term pain relief as well as short-term increased function by resecting pathological structures such as unstable articular cartilage, proliferative synovium, torn menisci and osteophytes [15].

Based on the available evidence, the National Institute for Health and Care Excellence (NICE) issued the following guidance [16] in 2007: “Referral for arthroscopic lavage and debridement should not be offered as part of treatment for osteoarthritis, unless the person has knee osteoarthritis with a clear history of mechanical locking”. A 2008 Cochrane review [17] of the evidence for knee arthroscopy concluded that there was no benefit, functionally or in terms of pain relief, from arthroscopic washout or debridement for knee OA, when compared to each other or with placebo. In the United States, there has been considerable discrepancy between actual clinical practice and the recommendation of the American Academy of Orthopaedic Surgeons against the use of arthroscopy for the treatment of knee OA [18] as nearly 1 in 5 patients had potentially been inappropriately treated with arthroscopy for knee OA [19]. To date, there has been no evaluation of the number of arthroscopic procedures performed in the UK on patients with knee OA since the 2007 NICE guidance [16] and 2008 Cochrane review [17] on arthroscopy for knee OA. Therefore, in order to assess whether current clinical practice is in accordance with the latest guidance and evidence, we looked at the number of arthroscopic procedures performed since 2000.