Does a corticosteroid injection plus exercise or exercise alone add to the effect of patient advice and a heel cup for patients with plantar fasciopathy? A randomised clinical trial

Key Points

1. Exercise prescription may not be essential for people suffering with plantar fasciopathy.
2. The use of corticosteroid injections was not associated with superior outcomes in this study.
3. There is no support that treatments beyond using heel cups, staying active, and minimizing aggravating activities are required initially for individuals with plantar fasciopathy.

BACKGROUND & OBJECTIVE

Plantar fasciopathy (frequently also referred to as plantar fasciitis or plantar heel pain) is the most common overuse issue affecting the foot (1) but despite this no firm conclusions exist regarding which treatments are most effective (2).

A best practice guide was recently developed by Morrissey et al (3) and acknowledged the lack of robust RCTs that had been performed with regard to corticosteroid injection and strength/resistance exercises, despite them often being used clinically. There were also no published papers of high enough quality regarding resistance/strength training to be included in the systematic review of the Morrissey et al paper.

Despite this, an entire generation of clinicians prescribe high load strength training for plantar fasciopathy sufferers, seemingly off the back of one key paper which suggested that there were superior outcomes in the foot function index after three months of strength training compared to stretching (with both groups also getting a heel cup) (4). However, this was quite a small study (n = 48) and it should be noted that there were no differences between the groups at later time points of 6 months and 12 months.

The aim of this current study was to identify if strength training was a worthy addendum to advice and a heel cup for patients with plantar fasciopathy, and then to also investigate if there was further benefit in adding a corticosteroid injection on top of all three of these interventions.

Plantar fasciopathy is accepted as being the most common overuse issue affecting the foot.

Patient education and advice is important, and this is in keeping with the best practice guide for plantar heel pain which also suggests it should be individualized.

METHODS

This study was a randomized trial with three groups (detailed below) and was single blinded in design (as it was not possible to blind the patients). Individuals with ultrasound confirmed plantar fasciopathy were recruited (n = 180) and randomized into one of three groups:

PA group (n=62): Patient advice, heel cup

PAX group (n=59): Patient advice, heel cup, exercise

PAXI group (n=59): Patient advice, heel cup, exercise, corticosteroid injection

Inclusion criteria were heel pain for over 3 months, pain on palpation of the medial calcaneal tubercle, plantar fascia thickness >4mm on ultrasound, and a mean pain of >3/10 on a visual analogue scale. Exclusion criteria were being under 18 years of age, systemic diseases such as diabetes, rheumatoid arthritis or spondyloarthritis, prior heel surgery, previous corsticosteroid injection for heel pain in 6 months prior, stiffness in the big toe joint which may prohibit exercises being performed, or any substantial changes to usual care in the last 4 weeks (e.g. started using insoles or changes activity levels).

This is what each of the interventions looked like:

Patient advice: oral information and leaflet, including information about pathology, risk factors and load management.

Heel cup: Silicone heel cup (MediDyne Healthcare) to be worn whenever wearing shoes.

Exercise: Heel raise with the toes in dorsiflexion on a rolled-up towel, as per Rathleff et al. protocol (4) with a load as heavy as possible to achieve an 8-rep max with as many sets as possible, separated with 2 min pauses between sets (see video).

EXERCISES FOR PLANTAR FASCIOPATHY

Injection: An ultrasound guided corticosteroid injection (1ml triamcinolone 20mg/ml and 1ml lidocaine 10mg/ml) performed by an experienced Rheumatologist with a medial approach.

Some of the baseline characteristics of the patients by group can be seen in the table.

The primary outcome measure for the study was the pain domain of the foot health status questionnaire, which ranges from 0 (the worst possible score) to 100 (the best possible score) at 12 weeks. This outcome measure was assessed at baseline and at 12 weeks with the patients attending hospital, and was also assessed at weeks 4, 26 and 52 via an emailed questionnaire.

RESULTS

The change in the pain domain of the foot health status questionnaire at the different time points across the groups can be seen in the table below, reported as mean (SD). Remember, the minimal important difference of the pain domain is 14.1 points (5).

In the final table below the adjusted mean differences (95% CI) between the groups are shown:

At 12 weeks, the only statistically significant difference was between PA and PAXI groups, favouring PAXI, but no significant difference between PA and PAX or PAX and PAXI.

Over 52 weeks, a statistically significant difference was also detected between PA and PAXI, but none between PA and PAX or PAX and PAXI.

However, despite these statistically significant differences identified between PA and PAXI the mean difference between them did not exceed the minimal important difference at any time, which may question the clinical significance of these findings.

LIMITATIONS

The study design was single blinded due to the nature of the interventions. It should be noted that approximately one third of the patients did not respond to the week 26 and 52 questionnaires, and as such the power of the long-term results may be influenced.

Furthermore, the demographic of the participants in this study should be considered when generalizing the results to the wider population; this study essentially consisted of individuals around 50 years old and with a body mass index of around 30. Caution may therefore be sensible if extrapolating these findings to very different populations (e.g. athletes?)

CLINICAL IMPLICATIONS

All three groups had clinically meaningful improvements in the primary outcome after 12 weeks, but there were no clinically relevant differences between the three treatment approaches. This indicates that there is no additional effect of exercises or injections over giving simple advice and a heel cup.

What is clear is that patient education/advice is important, and this is in keeping with the best practice guide for plantar heel pain which also suggests it should be individualized (3). Previous work has given some recommendations for clinicians when describing plantar heel pain to try to avoid invoking threat or impact a patient’s pain experience (6). Alongside this education, the use of heel cups (or similar/appropriate footwear or foot orthoses) seems obviously reasonable.

What this study suggests is that on average there may be not much to gain from strength exercises. However, this does not mean that we shouldn’t use them, just that they may not be essential. It is up to us to decide they will be included within the multi-modal management of heel pain for a given individual, and that this itself could (and probably should) be part of a shared decision-making process.

+STUDY REFERENCE

Riel H, Vicenzino B, Olesen J, Jensen M, Ehlers L, Rathleff M (2023) Does a corticosteroid injection plus exercise or exercise alone add to the effect of patient advice and a heel cup for patients with plantar fasciopathy? A randomised clinical trial. British Journal of Sports Medicine, Published Online First.

SUPPORTING REFERENCE

1. Sobhani, S., Dekker, R., Postema, K., & Dijkstra, P. U. (2013). Epidemiology of ankle and foot overuse injuries in sports: a systematic review. Scandinavian Journal of Medicine & Science in Sports, 23(6), 669-686.
2. Babatunde, O. O., Legha, A., Littlewood, C., et al. (2019). Comparative effectiveness of treatment options for plantar heel pain: a systematic review with network meta-analysis. British Journal of Sports Medicine, 53(3), 182-194.
3. Morrissey, D., Cotchett, M., J'Bari, A. S., et al. (2021). Management of plantar heel pain: a best practice guide informed by a systematic review, expert clinical reasoning and patient values. British Journal of Sports Medicine, 55(19), 1106-1118.
4. Rathleff, M. S., Mølgaard, C. M., Fredberg, U., et al. (2015). High‐load strength training improves outcome in patients with plantar fasciitis: A randomized controlled trial with 12‐month follow‐up. Scandinavian Journal of Medicine & Science in Sports,25(3), 292-300.
5. Landorf, K. B., & Radford, J. A. (2008). Minimal important difference: values for the foot health status questionnaire, foot function index and visual analogue scale. The Foot, 18(1), 15-19.
6. McGrath, R. L., Murray, A., Maw, R., & Searle, D. (2022). 'Collapsed arches', 'ripped plantar fasciae', and 'heel spurs': The painful language of plantar heel pain. New Zealand Journal of Physiotherapy, 50(2), 58-63.