Immediate and short-term effects of in-shoe heel-lift orthoses on clinical and biomechanical outcomes in patients with insertional Achilles tendinopathy

Key Points

1. This case series investigated immediate (following fitting) and short-term (2-weeks wear) effects of heel lifts in people with insertional Achilles tendinopathy.
2. Immediately after fitting and following 2-weeks of wear, clinically meaningful improvements in symptoms were observed.
3. Heel lifts may be a viable conservative option for management of insertional Achilles tendinopathy, but due to the limitations of case series design, further research is required to determine the beneficial effect that may be expected in clinical practice.

BACKGROUND & OBJECTIVE

Heel lifts are commonly prescribed in management of individuals with Achilles tendinopathy with the intention to improve symptoms by reducing tendon strain and compression by reducing ankle dorsiflexion (1-3). Although heel lifts have been reported to improve symptoms and quality of life after 2-weeks of wear in individuals with mid-portion Achilles tendinopathy (4), their effect in individuals with insertional Achilles tendinopathy is not understood.

The aim of this study was to determine the immediate and short-term effects of heel lifts on clinical and gait outcomes in people with insertional Achilles tendinopathy.

Heel lifts are commonly prescribed in management of individuals with Achilles tendinopathy with the intention to improve symptoms by reducing tendon strain and compression.

Positive immediate and short-term effects with little risk of adverse events provides preliminary support for heel lifts as part of the conservative management of patients with insertional Achilles tendinopathy.

METHODS

This prospective case series recruited participants with a clinical diagnosis of insertional Achilles tendinopathy who had a gait impairment (see Table 1). The more symptomatic side was included where symptoms were bilateral.

Participants attended two visits, two weeks apart, during which outcomes were measured under three conditions: without heel lifts, immediately after heel lift fitting and after two weeks wear. At the first visit outcomes were evaluated without using heel lifts (baseline) and immediately after heel lift fitting a pair of 20mm heel lifts (EVA model number TY-FC051) placed atop the insole of participants’ usual shoes. Participants wore the heel lifts for two weeks before returning for the second visit.

Primary outcomes were patient-reported symptom severity and pain during walking. Additional outcome measures included, quality of life, physical activity level, fear of movement, pain pressure threshold, gait analysis (spatiotemporal parameters and tibial tilt angle), expectation of benefit, patient satisfaction, global rating of change and adverse events (see Table 2).

RESULTS

21 participants completed baseline assessment and 20 participants completed 2-week follow-up. Participants were 60% female and mean (standard deviation) 51 (9.3) years of age and body mass index 31.6 (6.8) kg/m². Symptoms were mostly unilateral (13/20) and chronic with average duration of symptoms of 3.5 (8.1) years. Table 1 reports immediate and short-term effects.

Immediately after fitting heel lifts there was a small reduction in pain during walking (p = 0.043). Patient satisfaction with treatment was moderately high with a mean score of 6.75 (10 = very satisfied). Overall improvement appeared minimal with a global perceived improvement of 0.75 (0 = unchanged). Several differences in gait parameters were observed including increased speed (p = 0.007), increased stride length (p = 0.039), increased time spent in double support (p = 0.005), increased time spent during loading rate subphase (p < 0.001), reduced time spent during pre-swing subphase (p = 0.007) and increased maximum tibial tilt angle at midstance (p = 0.011).

Compliance wearing the heel lifts was high with rates of 86-100% while walking, running or participating in exercise classes during the 2-week intervention period. After two weeks of wear, symptom severity improved by 15% (7.7 points on VISA-A score, p = 0.006) but pain during walking was not different to baseline (p = 0.207). Median global rating of change scores improved by two points and 90% of patients were moderately to very satisfied with treatment. There were some differences in spatiotemporal gait parameters with faster walking speed (p = 0.012), increased stride length (p = 0.05) and increased double support (p = 0.014). Physical activity level, fear of movement and pain pressure threshold were not different to baseline (p > 0.05).

LIMITATIONS

• Case series design (absence of a control group and random allocation to treatment).

• Study was conducted in a cohort of middle-age obese participants and although this is a common demographic in patients with insertional Achilles tendinopathy, results may not be generalizable to all individuals with insertional Achilles tendinopathy.

• Walking speed was different across the 3 test conditions and so it is uncertain if changes that were observed - particularly spatiotemporal parameters and tibial tilt angle - were due to the heel lifts, walking speed, or a combination of both.

CLINICAL IMPLICATIONS

The results of this study should be interpreted within the limitations of case series design. Due to the absence of a control group (no intervention), it is unclear if the heel lift provides beneficial outcomes beyond natural course of the condition. Despite these limitations, case series are an important first step in identifying interventions that may have positive effects and that warrant evaluation in larger scale randomized trials (which are expensive and time consuming to conduct).

This case series demonstrated that heel lifts reduced pain during walking immediately after being fitted and symptom severity was improved after two weeks of wear. These immediate and short-term effects were statistically significant and of clinically meaningful magnitudes. Most patients were satisfied with their heel lifts and no adverse events were reported. Although case numbers were small, the authors reported from a secondary analysis that improvements in symptom severity were observed regardless of pathology at the insertion (e.g. with or without calcification and/or bony deformity).

Positive immediate and short-term effects with little risk of adverse events observed in this study provides preliminary support for heel lifts as part of the conservative management of patients with insertional Achilles tendinopathy. Further evaluation by high quality randomized clinical trials is required to determine the beneficial effect that may be expected in clinical practice and evaluate if effects are maintained over a longer period of time.

+STUDY REFERENCE

Alghamdi N, Pohlig R, Seymore K, Sions J, Crenshaw J, Gravare Silbernagel K (2024). Immediate and Short-Term Effects of In-Shoe Heel-Lift Orthoses on Clinical and Biomechanical Outcomes in Patients With Insertional Achilles Tendinopathy. Orthop J Sports Med, 12(2).

SUPPORTING REFERENCE

1. Wulf, M., Wearing, S. C., Hooper, S. L., Bartold, S., Reed, L., & Brauner, T. (2016). The Effect of an In-shoe Orthotic Heel Lift on Loading of the Achilles Tendon During Shod Walking. The Journal of Orthopaedic and Sports Physical Therapy, 46(2), 79–86.
2. Chimenti, R. L., Flemister, A. S., Ketz, J., Bucklin, M., Buckley, M. R., & Richards, M. S. (2016). Ultrasound strain mapping of Achilles tendon compressive strain patterns during dorsiflexion. Journal of Biomechanics, 49(1), 39–44.
3. Chimenti, R. L., Cychosz, C. C., Hall, M. M., & Phisitkul, P. (2017). Current Concepts Review Update: Insertional Achilles Tendinopathy. Foot & Ankle International, 38(10), 1160–1169.
4. Rabusin, C. L., Menz, H. B., McClelland, J. A., Evans, A. M., Malliaras, P., Docking, S. I., Landorf, K. B., Gerrard, J. M., & Munteanu, S. E. (2021). Efficacy of heel lifts versus calf muscle eccentric exercise for mid-portion Achilles tendinopathy (HEALTHY): a randomised trial. British Journal of Sports Medicine, 55(9), 486–492.