Foot orthoses for plantar fasciitis and plantar heel pain: what the evidence shows

Plantar fasciitis is a common cause of heel pain, affecting many people. It involves pain and stiffness in the plantar fascia, a thick band of tissue on the bottom of the foot that connects the heel bone to the toes [3]. Foot orthoses, also known as shoe inserts, are often recommended as a treatment for this condition [1, 2, 3]. These devices are designed to support the foot and may help reduce stress on the plantar fascia [1].

This article reviews what scientific studies show about how effective foot orthoses are for plantar heel pain. It looks at whether they help with pain and function, how long their effects last, and how different types of orthoses compare. It also explores other treatment options, such as specific exercises.

Understanding Foot Orthoses

Foot orthoses are devices worn inside shoes to support, align, or correct foot posture [1]. They can be made from various materials, such as foam or plastic, and vary in their stiffness and design [3].

There are generally two main types of foot orthoses discussed in research: * Prefabricated orthoses are ready-made inserts that can be purchased off-the-shelf [3]. They are often made from firm foam [3]. * Custom-made orthoses are specifically designed and molded to fit an individual's foot [2, 3]. These are typically made from semi-rigid plastic [3].

In some studies, "sham" orthoses are used as a comparison. These are often soft, thin foam inserts that look like orthoses but are not designed to provide specific support or correction, helping researchers understand if any benefits come from the orthosis itself or other factors [3].

Foot Orthoses and Plantar Heel Pain: A Meta-Analysis Review

A systematic review and meta-analysis published in the British Journal of Sports Medicine in 2018 looked at the effectiveness of foot orthoses for adults with plantar heel pain [1]. This type of study combines results from multiple independent studies to provide a more comprehensive picture [1]. The researchers included 19 trials with a total of 1660 participants [1]. They focused on how orthoses affected pain and function over different time periods: * Short term: 0 to 6 weeks [1]. * Medium term: 7 to 12 weeks [1]. * Longer term: 13 to 52 weeks [1].

Short-Term Effects (0 to 6 weeks)

In the short term, the review found "very low-quality evidence" that foot orthoses do not reduce pain or improve function [1]. This means that based on the available studies, it is uncertain if orthoses provide benefits in the first six weeks of use [1].

Medium-Term Effects (7 to 12 weeks)

For the medium term, there was "moderate-quality evidence" that foot orthoses were more effective than sham foot orthoses at reducing pain [1]. The studies showed a "standardised mean difference" of -0.27, with a 95% confidence interval of -0.48 to -0.06 [1]. This suggests a small to moderate reduction in pain [1]. However, the review noted that it is "uncertain whether this is a clinically important change," meaning it's unclear if this statistical difference translates to a noticeable improvement in daily life for patients [1].

Regarding function, the review found no improvement in the medium term [1].

Longer-Term Effects (13 to 52 weeks)

Similar to the short term, the review found "very low-quality evidence" that foot orthoses do not reduce pain or improve function in the longer term [1]. This suggests that any potential pain relief seen in the medium term may not last over several months [1].

Custom vs. Prefabricated Orthoses in the Meta-Analysis

The meta-analysis also compared custom-made foot orthoses with prefabricated ones [1]. It found "no difference at any time point" between these two types of orthoses [1]. This suggests that, for plantar heel pain, custom-made orthoses may not offer greater benefits than prefabricated ones [1].

Custom-Made Foot Orthoses: A Cochrane Review Perspective

Another important review, a Cochrane systematic review published in 2008, specifically evaluated the effectiveness of custom-made foot orthoses for different types of foot pain [2]. Cochrane reviews are known for their rigorous methods in assessing medical evidence. This review included eleven trials with 1332 participants [2].

Findings for Plantar Fasciitis

For plantar fasciitis, the review concluded that "it is unclear if custom-made foot orthoses were effective" [2]. The evidence level for plantar fasciitis was described as "silver level," which indicates a moderate level of evidence but not the highest "gold level" [2]. You can learn more about this condition in our plantar fasciitis patient guide.

Other Foot Pain Conditions

While the focus here is on plantar fasciitis, the Cochrane review did find custom-made foot orthoses to be effective for some other conditions [2]: * Painful pes cavus (high arch foot): The "Number Needed to Treat to Benefit" (NNTB) was 5, meaning 5 people would need to be treated with custom orthoses for one person to benefit [2]. * Rearfoot pain in rheumatoid arthritis: NNTB was 4 [2]. * Foot pain in juvenile idiopathic arthritis (JIA): NNTB was 3 [2]. * Painful hallux valgus (bunion): NNTB was 6 [2].

However, the review also noted that for hallux valgus, surgery was even more effective than custom orthoses [2]. For JIA, non-custom foot orthoses appeared to be just as effective, though the analysis might not have had enough power to definitively detect a difference [2].

The review also stated that custom-made foot orthoses were a safe intervention in all studies [2].

Overall Conclusion of the Cochrane Review

The authors of the Cochrane review concluded that there is "limited evidence on which to base clinical decisions regarding the prescription of custom-made foot orthoses for the treatment of foot pain" [2]. This highlights the need for more high-quality research to fully understand their benefits. For a broader discussion of orthotics, you might find our article do foot orthotics work? helpful.

A Closer Look at Long-Term Effectiveness: The Landorf Trial

A specific randomized trial by Landorf and colleagues, published in Archives of Internal Medicine in 2006, aimed to investigate both the short-term and long-term effectiveness of foot orthoses for plantar fasciitis [3]. This study was a "pragmatic, participant-blinded, randomized trial," meaning participants didn't know which type of orthosis they received, and the study design aimed to reflect real-world conditions [3].

The trial included 135 participants with plantar fasciitis and followed them for 12 months [3]. Participants were randomly assigned to one of three groups: 1. Sham orthosis: A soft, thin foam insert [3]. 2. Prefabricated orthosis: A firm foam insert [3]. 3. Customized orthosis: A semi-rigid plastic insert [3].

Short-Term Results (3 months)

After three months, the study found that both prefabricated and customized orthoses showed benefits compared to the sham orthoses [3]. * Pain: The mean pain score (on a scale of 0-100) was 8.7 points better for the prefabricated orthoses compared to sham (95% confidence interval: -0.1 to 17.6; P = .05) [3]. For customized orthoses, it was 7.4 points better than sham (95% confidence interval: -1.4 to 16.2; P = .10) [3]. While the prefabricated group showed a statistically significant improvement in pain, the customized group's improvement was not statistically significant at this time point [3]. * Function: Both prefabricated and customized orthoses showed statistically significant improvements in function [3]. Compared to sham orthoses, the mean function score (on a scale of 0-100) was 8.4 points better for prefabricated orthoses (95% confidence interval: 1.0 to 15.8; P = .03) and 7.5 points better for customized orthoses (95% confidence interval: 0.3 to 14.7; P = .04) [3].

The study also concluded that the customized and prefabricated orthoses used in this trial had "similar effectiveness" in the short-term treatment of plantar fasciitis [3].

Long-Term Results (12 months)

Crucially, the Landorf trial found "no significant effects on primary outcomes at the 12-month review" [3]. This means that the small short-term benefits in function and potential pain reduction observed at three months did not continue to be significant when compared to the sham device after a full year [3]. The study's conclusion explicitly stated that foot orthoses "do not have long-term beneficial effects compared with a sham device" [3].

Beyond Orthoses: High-Load Strength Training

While orthoses are a common treatment, other approaches are also studied. A randomized controlled trial by Rathleff and colleagues, published in Scandinavian Journal of Medicine & Science in Sports in 2015, investigated a different approach: high-load strength training [4].

This study involved 48 patients who had plantar fasciitis confirmed by ultrasound [4]. Participants were divided into two groups: 1. Stretch group: Received shoe inserts and performed daily plantar fascia-specific stretching [4]. 2. Strength group: Received shoe inserts and performed high-load progressive strength training every second day [4].

High-Load Strength Training Protocol

The high-load strength training involved a specific exercise: unilateral heel raises with a towel inserted under the toes [4]. This exercise was performed every second day [4].

Results at 3 Months

At the three-month mark, the strength group showed superior self-reported outcomes [4]. Their Foot Function Index (FFI) score was 29 points lower than the stretch group (95% confidence interval: 6-52, P = 0.016) [4]. A lower FFI score indicates better function and less pain. The researchers concluded that high-load strength training "may aid in a quicker reduction in pain and improvements in function" [4].

Longer-Term Results (1, 6, and 12 months)

However, at the one-month, six-month, and twelve-month follow-ups, there were "no differences between groups" in the FFI or any other secondary outcomes [4]. At 12 months, the FFI was 22 points in the strength group and 16 points in the stretch group, with no statistically significant difference [4]. This suggests that while high-load strength training may offer quicker improvements in the short term, its long-term benefits compared to stretching combined with inserts were not significantly different in this study [4].

What this means for you

When considering options for plantar heel pain, it's helpful to understand the evidence for different treatments. Research suggests that foot orthoses may offer some reduction in pain in the medium term (around 7 to 12 weeks) when compared to sham devices [1]. However, this pain reduction may not be considered clinically significant by some, and orthoses generally do not show benefits for improving function or for reducing pain in the short term (0-6 weeks) or longer term (13-52 weeks) [1].

The evidence also indicates that custom-made orthoses may not be more effective than prefabricated ones for plantar heel pain [1, 3]. In one trial, any early benefits from both types of orthoses did not persist after 12 months when compared to a sham device [3].

Beyond orthoses, specific exercise programs like high-load strength training have shown promise for quicker improvements in pain and function in the short term (around 3 months) compared to stretching, although long-term differences were not observed in one study [4].

Deciding on the best approach for your plantar heel pain involves considering your specific symptoms, lifestyle, and individual needs. This is where a regulated health professional can provide guidance. In Alberta, regulated health professionals are governed by regulatory colleges under the Health Professions Act [5]. These colleges ensure that professionals meet standards of practice and ethical conduct, helping to protect the public [5].

A regulated health professional — for example a podiatrist, who in Alberta is registered with the College of Podiatric Physicians of Alberta — can assess your specific situation and help you understand whether a prefabricated insert, a custom device, or a loading exercise program might be suitable for you [5]. Note that not every occupation that makes or fits orthoses is a regulated health profession: orthotists, for instance, are not listed on Alberta's register of regulated health professions, so there is no provincial college there to verify a registration against [5]. That is not a judgement about anyone's skill — it simply means the check available to you is a different one, and it is fair to ask a provider directly about their training and credentials. They can discuss the potential benefits and limitations of each option based on your individual presentation and the current evidence. For example, you might look for orthotics providers in Calgary or podiatrists in Calgary.

A licensed professional can help you weigh the options, considering: * The potential for short-to-medium term pain relief from orthoses [1]. * The similar effectiveness often found between prefabricated and custom orthoses for plantar fasciitis [1, 3]. * The role of exercise programs, such as high-load strength training, which may offer quicker initial improvements in some cases [4]. * The importance of a comprehensive treatment plan that might combine different approaches.

A regulated health professional can assess whether this fits you and help you create a personalized plan to manage your plantar heel pain.