Description of the condition
Osteoarthritis (OA) is a chronic and degenerative disorder associated with joint pain and loss of joint function. OA can affect any synovial joint but is found most frequently in the hip, knee and hand, the majority of these patients present with primary OA (idiopathic disease) (Buckwalter 2004; Kalunian 2012; Witteveen 2008). Reliable figures on the prevalence of OA in other joints are not readily available but estimates suggest that the incidence of symptomatic ankle OA is 1% to 4% in the adult population (Cushnaghan 1991; Peyron 1984). In contrast to knee and hip OA, 70% to 78% of patients with ankle OA present themselves with secondary, post-traumatic disease, the remainder is primary OA as well as inflammatory diseases, such as rheumatoid arthritis and gout (Saltzman 2005; Valderrabano 2009). Ankle trauma occurs in many patients at a relatively young age (Agel 2005; Saltzman 2005). Consequently, the expected life span of many patients with ankle OA is significantly longer than the life span of hip or knee OA patients; this affects their quality of life for a substantial amount, Saltzman 2006 demonstrated that the self reported physical function in patients with symptomatic ankle OA quantified using the Short Form-36 (SF-36) questionnaire was equivalent to or worse than that of patients with end-stage kidney disease or congestive heart failure suggesting that these patients are seriously impaired.
Description of the intervention
In clinical practice, patients diagnosed with end-stage OA (Kellgren Lawrence 3 or 4 and van Dijk 3) are offered operative treatment if they have significant clinical symptoms (Harada 2011; van Dijk 1997).These patients are treated by arthrodesis, ankle replacement or osteotomy. Surgical treatment is specifically reserved for end stage arthritis. It is considered to be harmful due to short and long term complications. Complications consist of wound healing problems, infectious disease, non or delayed union and OA of adjacent joints due to overloading (Chang 2013; Deorio 2008; Jung 2007; Krause 2012; Rippstein 2012; Suckel 2012). Operative treatment is therefore not considered in an early phase of OA, it remains a challenge to treat patients that are diagnosed with a low grade OA of the ankle (Kellgren Lawrence 1, 2 or 3 and Van Dijk 1 or 2) (Harada 2011; van Dijk 1997). They are young and they experience serious disabilities which prevent these patients from participating in more heavily laboured work as well as sports activities. Several conservative treatment options are available, however evidence of the benefits and harms of these options are lacking.
The conservative treatment of symptomatic ankle OA, like general OA, consists mainly of treating symptoms like pain and stiffness. Since no cure is available at this point another treatment goal is preventing deterioration of the joint (Towheed 2006). Non-pharmacological therapy is to be considered the foundation for the successful medical management of general OA (Hochberg 2012; Zhang 2008; Zhang 2010).There are systematic reviews published for knee and hip OA and include weight reduction (BMI > 25), physiotherapy and occupational therapy (Brosseau 2011; Brouwer 2005; Rutjes 2009; Rutjes 2010). For ankle OA offloading the joint by brace, cane, rocker sole or inlay can reduce the pain as well (Bartels 2007; Brosseau 2003; Fransen 2009; Janisse 1998; Kempson 1991; Messier 2005; McGuire 2003; Wu 2004). If this is not successful a painkiller can be added. In case of pain relief several options are available, e.g. painkillers like acetaminophen, opioids and non-steroidal anti-inflammatory drugs (NSAIDs) (Cepeda 2006; Garner 2005; Nuesch 2010; Towheed 2006). Hyaluronic acid has been shown to reduce pain as well (Chang 2013; Cohen 2008; Pleimann 2002; Salk 2006; Sun 2006; Witteveen 2008; Witteveen 2010). The benefit of glucosamine/chondroitin for pain reduction in general OA was not shown (Towheed 2005).
How the intervention might work
Ankle OA pain can be reduced by off loading the joint through rest, wearing a brace or using a cane. A cane can reduce the amount of bodyweight going through the ankle joint by 25% (Kempson 1991). Rockersoles are thought to off load the ankle joint by decreasing the ankle motion at heel strike to push off during walking (Wu 2004). Weight loss by dietary adjustments or exercises are thought to off load a joint as well (Bartels 2007; Brosseau 2003; Fransen 2009). In Messier 2005, each pound of weight loss created a 4-fold reduction in the load exerted by step at the knee during daily activities. Shoe adjustment like inlays can correct alignment issues and in this way off load a part of the joint thus creating pain reduction (Janisse 1998; McGuire 2003). It is possible that in this way the joint can be preserved from further deteriorating. Several analgesics are available like acetaminophen, opioids and NSAIDs. They either act as a simple analgesic, have anti inflammatory effects, a sedative effect or a combination. Recommendations for hip, knee or hand OA are well described (Hochberg 2012). Hyaluronic acid (visco supplementation) is thought to restore rheologic properties of the joint by creating a more viscoelastic synovial fluid which improves mobility and restores the natural protective function of the joint, like shock absorption during gait (Balazs 1993; Bellamy 2006). Several studies have shown pain reduction as well (Chang 2013; Cohen 2008; Pleimann 2002; Salk 2006; Sun 2006; Witteveen 2008; Witteveen 2010). Glucosamine/chondroitine may be potentially chondro protective and may modify the progression and course of general OA. However, up until now no evidence has been found to prove this theory (Towheed 2005).
Why it is important to do this review
Lots of treatment modalities are offered, however no clear cut treatment algorithm for ankle OA is used. The choice of treatment depends on the severity of the disease, the patients' age, medical and social history and the level of physical activity expected to be demanded of the joint. For knee and hip OA several treatment algorithms are advocated (Kalunian 2012; Pendleton 2000; Tannenbaum 2000; Towheed 2005; Towheed 2006; Zhang 2008; Zhang 2010). However, since ankle OA may be caused by a different mechanism, it is not unthinkable that these patients need a different treatment.
At this point there is no evidence based treatment algorithm for ankle OA. Several papers have been published concerning the cause of ankle OA and the possible conservative and operative treatment strategies. The conservative section mainly sums up the possibilities, however no algorithm is suggested (Demetriades 1998; Katcherian 1998; Martin 2007; Rao 2010; Rhys 2003).This review will be conducted to find evidence for the benefits and harms of non-pharmacological and pharmacological treatment of ankle OA in general or by stage of the disease. We will try to provide a synthesis of the evidence as a base for future treatment guidelines.