Injected corticosteroids for treating plantar heel pain in adults.

BACKGROUND

Plantar heel pain, commonly resulting from plantar fasciitis, often results in significant morbidity. Treatment options include nonsteroidal anti-inflammatory drugs (NSAIDs), orthoses, physical therapy, physical agents (e.g. extracorporeal shock wave therapy (ESWT), laser) and invasive procedures including steroid injections.

OBJECTIVES

To assess the effects (benefits and harms) of injected corticosteroids for treating plantar heel pain in adults.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials (the Cochrane Library), MEDLINE, Embase, CINAHL, clinical trials registries and conference proceedings. Latest search: 27 March 2017.

SELECTION CRITERIA

Randomised and quasi-randomised trials of corticosteroid injections in the treatment of plantar heel pain in adults were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

At least two review authors independently selected studies, assessed risk of bias and extracted data. We calculated risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcome measures. We used a fixed-effect model unless heterogeneity was significant, when a random-effects model was considered. We assessed the overall quality of evidence for individual outcomes using the GRADE approach.

MAIN RESULTS

We included a total of 39 studies (36 randomised controlled trials (RCTs) and 3 quasi-RCTs) that involved a total of 2492 adults. Most studies were small (median = 59 participants). Participants' mean ages ranged from 34 years to 59 years. When reported, most participants had heel pain for several months. The trials were usually conducted in outpatient specialty clinics of tertiary care hospitals in 17 countries. Steroid injection was given with a local anaesthetic agent in 34 trials. Follow-up was from one month to over two years. With one exception, trials were assessed at high risk of bias in one or more domains, mostly relating to lack of blinding, including lack of confirmation of allocation concealment. With two exceptions, we rated the available evidence as very low quality, implying in each case that we are 'very uncertain about the estimate'.The 39 trials covered 18 comparisons, with six of the seven trials with three or four groups providing evidence towards two comparisons.Eight trials (724 participants) compared steroid injection versus placebo or no treatment. Steroid injection may lead to lower heel pain visual analogue scores (VAS) (0 to 100; higher scores = worse pain) in the short-term (< 1 month) (MD -6.38, 95% CI -11.13 to -1.64; 350 participants; 5 studies; I² = 65%; low quality evidence). Based on a minimal clinically significant difference (MCID) of 8 for average heel pain, the 95% CI includes a marginal clinical benefit. This potential benefit was diminished when data were restricted to three placebo-controlled trials. Steroid injection made no difference to average heel pain in the medium-term (1 to 6 months follow-up) (MD -3.47, 95% CI -8.43 to 1.48; 382 participants; 6 studies; I² = 40%; low quality evidence). There was very low quality evidence for no effect on function in the medium-term and for an absence of serious adverse events (219 participants, 4 studies). No studies reported on other adverse events, such as post-injection pain, and on return to previous activity. There was very low quality evidence for fewer treatment failures (defined variously as persistent heel pain at 8 weeks, steroid injection at 12 weeks, and unrelieved pain at 6 months) after steroid injection.The available evidence for other comparisons was rated as very low quality. We are therefore very uncertain of the estimates for the relative effects on people with heel pain of steroids compared with other interventions in:1. Tibial nerve block with anaesthetic (2 trials); orthoses (4 trials); oral NSAIDs (2 trials); and intensive physiotherapy (1 trial).2. Physical modalities: ESWT (5 trials); laser (2 trials); and radiation therapy (1 trial).3. Other invasive procedures: locally injectable NSAID (1 trial); platelet-rich plasma injections (5 trials); autologous blood injections (2 trials); botulinum toxin injections (2 trials); cryopreserved human amniotic membrane injection (1 trial); localised peppering with a needle (1 trial); dry needling (1 trial); and mini scalpel needle release (1 trial).We are also uncertain about the estimates from trials testing different techniques of local steroid injection: ultrasonography-guided versus palpation-guided (5 trials); and scintigraphy-guided versus palpation-guided (1 trial).An exploratory analysis involving pooling data from 21 trials reporting on adverse events revealed two ruptures of plantar fascia (reported in 1 trial) and three injection site infections (reported in 2 trials) in 699 participants allocated to steroid injection study arms. Five trials reported a total of 27 participants with less serious short-term adverse events in the 699 participants allocated steroid injection study arms. Reported treatments were analgesia, ice or both. Given the high risk of selective reporting for these outcomes and imprecision, this evidence was rated at very low quality.

AUTHORS' CONCLUSIONS: We found low quality evidence that local steroid injections compared with placebo or no treatment may slightly reduce heel pain up to one month but not subsequently. The available evidence for other outcomes of this comparison was very low quality. Where available, the evidence from comparisons of steroid injections with other interventions used to treat heel pain and of different methods of guiding the injection was also very low quality. Although serious adverse events relating to steroid injection were rare, these were under-reported and a higher risk cannot be ruled out.Further research should focus on establishing the effects (benefits and harms) of injected steroids compared with placebo in typical clinical settings, subsequent to a course of unsuccessful conservative therapy. Ideally, this should be preceded by research, including patient involvement, aimed to obtain consensus on the priority questions for treating plantar heel pain.