Reachout Orthopedics - Issue 2

unsaponfiables, vitamin D, turmeric, tricyclic agents, glucosamine and risedronate [44–46]. Intra-Articular Injections Intra-articular (IA) injections have been in- vestigated more than any other non-surgical approach for foot and ankle OA. Although ankle OA has a lower prevalence than first MTPJ or midfoot OA, the majority of studies used participants with ankle OA. A 2018 systematic review [55] found 22 studies that evaluated the effects of IA injections in people with ankle OA; however, only five of these were RCTs [56–60]. Of the five RCTs, three compared hyaluronic acid (HA) to saline [56, 57, 59], one compared HA to exercise therapy [58], and one compared HA and rehabilita- tion exercise to an injection of botulinum toxin type A. Pooled RCT results from the systematic review showed HA significantly improved ankle OA symptoms over saline at 6 months [55]. However, no trial blinded the administering physician, all were generally small ( n = 20–75), and most had inadequate or unclear randomisation and/or alloca- tion concealment. Case series on the effects of platelet-rich plasma, corticosteroids and mesenchymal stem cell injections also suggest symptomatic improvements; however, these trials are all small and lack a control group, which limits interpretation [55]. Larger studies with adequate randomisation, control and blinding are needed before firm conclu- sions regarding the efficacy of IA injections for ankle OA can be made. In the first MTPJ, there has been one RCT comparing an IA injection of HA to saline [61] and one comparing HA to a corticosteroid injection [62]; however, only the former was adequately powered and reported randomi- sation and blinding information. Clinically meaningful reductions in first MTPJ pain were observed in both the HA and saline groups over 6 months [61] and in the HA and corticosteroid group over 3 months [62]. However, there were no statistically significant between-group differences in change in pain in either study. There have only been two un- controlled studies comparing IA injections for midfoot OA, both of which used a corticoster- oid [63, 64]. Results from both studies showed symptomatic improvements in the short term (3–4 months); however, these positive clinical responses were generally not maintained in the longer term (12 months). Conservative Treatments There is little research on conservative treatment options for OA of the foot and ankle. In fact, there are no RCTs investigating management strategies for multi-joint foot OA, and high-quality trials investigating single-joint foot or ankle OA are also lacking. To date, there have only been two non-pharmacological non-surgical RCTs published on OA of the first MTPJ [65, 66], three small pilot studies for midfoot OA [6, 67, 68] and no clinical trials for conservative treatment for ankle OA. Notably, no study has investigated the effects of core OA management strategies (derived from hip and knee OA trials) recommended by international OA clinical guidelines [44–46], with the exception of one small trial [65]. This study assessed the addition of a single foot- strengthening exercise, as well as sesamoid mobilisation and gait training, to a range of other physical interventions, and reported significant improvements in strength and function for the intervention group. However, the small sample size ( n = 20), use of multiple interventions and lack of adequate control precludes an understanding of the effects of strength exercise on foot OA-related pain. Although no study has investigated the effects of aerobic exercise on foot or ankle OA symptoms, one cohort study of 221 participants aged between 40 and 91 years reported that regular exercise did not increase the risk for progression of foot OA [69]. The only other non-pharmacological non- surgical foot OA RCT compared the effects of rocker-soled footwear with prefabricated foot orthoses in 102 participants with OA of the first MTPJ [66]. The results showed that there were clinically meaningful symptomatic improvements in both groups; however, there were no between-group differences. It is worth noting that there were fewer AEs and greater adherence in the foot orthoses group. Of the three small studies to assess a conservative intervention for midfoot OA, all used a foot orthosis/insert. The first inves- tigated the effects of a full-length flat carbon graphite insert in 20 female patients with midfoot OA, and found symptomatic im- provements with the intervention, albeit the study lacked adequate control [68]. Another non-randomised study compared the addi- tion of a rigid carbon fibre footplate (insert) to custom semi-rigid foot orthoses in 57 par- ticipants with midfoot OA and found similar clinical improvements in pain, function and walking ability in both groups [67]. The final trial was a feasibility study in which 37 partici- pants with symptomatic radiographic midfoot OA were randomised to receive a pair of semi- custom foot orthoses or a sham device [6]. Both groups reported improvements in pain, function and global impression of change over 12 weeks; however, benefits were greater in the intervention group. Gaps in Our Knowledge and Key Areas for Clinical Focus The burden of foot and ankle OA has not been well-understood until recently, and the condition has been neglected in clinical research. Consequently, there is a plethora of questions regarding the impact of foot and ankle OA in the community and its optimal management in the clinical setting. Perhaps most pressing is the urgent need for clinical trials investigating core management strategies recommended by international OA clinical guidelines, such as education and advice, exercise and weight loss where appropriate. The condition is a leading cause for consulting a general practitioner [70], and general practitioners largely manage the condition using medication, including for new presentations [36]. Thus, more clinical trials on the efficacy and safety of analgesic and anti-inflammatory medications for foot and ankle OA are also needed. Indeed, dosing is inferred based mainly on the larger knee and hip joints, and, while these may be appropriate, it would be useful for clinicians to be able to recommend evidence-based dosing specifically for foot and ankle OA. Likewise, given the strong association between foot and ankle OA and advancing age [5] and co- morbidities [7, 36] (as for most OA), clinical research on the short- and long-term benefits and harms of pharmacological treatments for older people (e.g. >70 years) and those with Evidence concerning opioid use is poor, and toxicity- related AEs (particularly in the elderly), in addition to dependence, remain serious concerns. Cont'd on page 28... 22