Pearls On Treating Plantar Fasciitis In Athletes

Author(s): 
Dianne Mitchell, DPM, FAAPSM, FACFAOM

As podiatrists, we see plantar fasciitis in our offices many times each day, especially in athletes. We know what it is and have a good idea of what causes it.    However, with the numerous treatment modalities available, why aren’t all of our patients pain-free? Why do we have patients with lingering pain? Are we treating them wrong? Are they misdiagnosed? Are they non-adherent? I will reexamine how we look at plantar fasciitis in an attempt to improve our success rates in effectively treating and eliminating this mechanically induced pain.    What mechanism generates plantar fasciitis? There are two pathways: intrinsic and extrinsic.1,2 However, every single patient who over-trains or wears a broken-down shoe does not develop plantar fasciitis. Therefore, the more important factors to evaluate are intrinsic, such as supination of the midtarsal joint. Intrinsic factors result in torsion of the plantar fascia, generating pain and inflammation.    Kogler and colleagues in 1999 looked specifically at which foot positions place stretch and higher strain on the plantar fascia, as these positions would presumably create pain.3 Their goal was to quantify strain through the plantar fascia tissue with different orthotic wedge combinations in static stance using a cadaveric model. The 6-degree wedge combinations included a neutral load without any wedge followed by eight additional combinations as either a varus or valgus wedge applied to the rearfoot and/or the forefoot. Plantar fascial strain was lower in the three scenarios with forefoot valgus wedges. This likely controlled midtarsal joint supination by adding a pronatory torque on the forefoot and plantarflexion of the first metatarsal. This study could be a key in effectively treating mechanically induced plantar fasciitis with functional foot orthotics.4    There are numerous treatment options for plantar fasciitis.1,2 In 2010, the Journal of Foot and Ankle Surgery published a Clinical Practice Guideline for the treatment of heel pain.1 Once one has established the heel pain as mechanical in nature, the algorithm recommends stretching, icing, over the counter heel cups or orthotics, reduced activities, anti-inflammatories, padding/strapping, cortisone injection, weight loss, and avoiding bare feet and flat shoes. If these modalities fail, the next treatment level includes a night splint, custom orthotics, more injections or immobilization. Beyond that, consider surgery after ensuring that the diagnosis is correct and after six months of conservative care.    Often, patients who get a diagnosis of plantar fasciitis from a primary care doctor have already tried rest, ice and anti-inflammatories with no symptom improvement by the time they arrive in the podiatrist’s office. Some come in with a padded heel cup or an over-the-counter soft or semi-rigid orthotic also complaining that the pain is still very much present. Patients may report the inability to “rest” if their jobs require standing or squatting with or without the addition of lifting items. Many athletes do not want to stop their sport and did not receive alternatives to stay active and protect the feet.

A Closer Look At The Role Of Orthotic Therapy

The research indicates that the best way to address foot mechanics is with a functional foot orthotics device. Additionally, we incorporate a gentle stretching program to address the associated structures, as an equinus component is commonly present. We also incorporate a night splint to aid in pain relief and for post-static dyskinesia. Discussions of either modified work duty or “relative rest,” specifically looking at cross-training options, are an essential treatment component. With this approach, the need for cortisone injection has diminished significantly in my experience.    In 1991, Scherer looked at a group of heel pain sufferers to determine whether changing foot mechanics can relieve symptoms.6 The results suggested yes, with 90 percent of subjects reporting over 80 percent pain relief with either taping or orthotics controlling midtarsal joint supination. However, taping is a poor option for long-term use in comparison to functional foot orthotics, since it requires patients to be able to tape their feet daily.    Many authors have attested to the lack of consistency among numerous studies when attempting to evaluate the success of over-the-counter and custom molded functional foot orthotics in treating plantar fasciitis. While many studies do indeed show orthotics to be a successful treatment modality, there are too many variables to allow comparison. For example, with orthoses one must consider type of casting (semi- or non-weightbearing), foot position, prescription parameters, shell materials, padding, posting, etc. All are relevant factors, but often go uncontrolled and/or undefined in the studies.7-23 Also, some studies consider a heel cup to be an orthotic device and some studies do consider the shoes the orthoses are in while others simply do not.    In 1996, Kogler and colleagues hypothesized that if an orthotic device were effectively supporting the arches of the foot, then the strain through the plantar fascia should decrease along with the pain.5 The authors felt that reducing the tension through the plantar fascia tissue was important in treating painful plantar fasciitis. While this was a cadaveric and static study, it evaluated multiple foot orthotics and compared them to a barefoot condition. The results suggest that specifically designed orthotic devices will indeed decrease strain through the tissue. Further, the study says one can alter the materials used for orthotic construction, and slow both the time to load the tissue and the rate at which the foot achieves maximum strain levels. This presumably decreases trauma to the tissue.    In 2001, Martin and coworkers performed a prospective study evaluating mechanical treatment for plantar fasciitis with over-the-counter and custom-molded orthotics and a night splint.21 The custom devices were fabricated from a scanner with the foot held in subtalar joint neutral with the midtarsal joint maximally pronated. The patient wore a rigid shell with a rearfoot post and no topcover. The over-the-counter device was also rigid but without a rearfoot post and no topcover and the night splint was a posterior device. The authors found all devices to be effective, which reiterates the importance of mechanical control of the foot.    However, adherence was a large issue in the study.21 Only 76 percent of subjects completed this study with the largest losses in the over-the-counter orthotic and night splint group, 21 percent and 26 percent respectively. Only 7 percent of subjects dropped out of the custom molded orthotic group. Dropouts included patients who had continued pain, poor adherence, and were not tolerating the devices. Perhaps custom molded orthotic devices would have yielded better outcomes if they provided a glove-like fit into the arch to prevent excessive tension on the plantar fascia.    In 2009, Baldassin and colleagues performed a randomized controlled trial evaluating the effectiveness of prefabricated and custom molded foot orthoses made from ethylene vinyl acetate (EVA).11 They followed patients for eight weeks and found a significant reduction in pain in both orthotic groups over the short timeframe of the study, but no significant difference between treatment groups. The concern with this study is the potential for material breakdown with long-term use. Polypropylene, for example, has a much better shape memory and life expectancy compared to soft materials like EVA.    In 2013, Walther and coworkers wanted to evaluate different prefabricated orthotics for first line immediate treatment of plantar fasciitis.7 They used a thin “no support” device, a soft device, and a rigid device, both with topcovers. They found that the rigid device was superior regarding patient pain reduction and the time patients took to achieve the outcome. Again, a more rigid device outperformed a soft device. Practitioners should consider the possibility of improved outcomes if the rigid device were custom molded to the patient’s foot versus simply being off-the-shelf for the average foot shape.

Insights On The Goals Of Functional Foot Orthotics

So, what are the goals of an effective functional foot orthotic in treating plantar fasciitis? How do we control the mechanics behind this painful diagnosis to reduce pain to zero and treat our patients effectively? The key is controlling supination of the midtarsal joint and the associated torsion of the plantar fascia.    Custom functional foot orthotics require casting the patient in a supine position with the subtalar joint neutral and midtarsal joint maximally pronated.2,24-26 The orthotic shell should be constructed out of semi-rigid polypropylene with minimal arch fill in order to get the device to fit the foot like a glove for the best stress transfer to the entire plantar aspect of the foot.2 One can add a plantar fascia groove for a prominent plantar fascia to prevent irritation on the tightly fitting device. A wide device with a deep heel cup will provide increased contact surface area between the foot and the device for improved control.    One can best achieve rearfoot control with a flat rearfoot post for better stability.2 After evaluating the resting calcaneal stance position, invert the device and/or add a medial skive as needed to control the hindfoot. Finally, based on Kogler’s study, consider applying a forefoot valgus wedge beneath the topcover to decrease plantar fascia strain.3-5

In Conclusion

With a properly constructed functional foot orthotic, the symptoms of plantar fasciitis should be minimal. While this may very well require a stretching program and a night splint, along with additional treatment modalities and patient adherence, we should be able to treat plantar fasciitis in athletes better and faster.    Dr. Mitchell is a Fellow of the American Academy of Podiatric Sports Medicine and is board certified by the American Board of Podiatric Medicine. She is in private practice with Mercy Medical Group, Inc. in Sacramento, Calif. References 1. Thomas JL, Christensen JC, Kravitz SR, et al. The diagnosis and treatment of heel pain: a clinical practice guideline–revision. J Foot Ankle Surg. 2010; 49(3Suppl):S1-S19. 2. Scherer PR. Recent Advances in Orthotic Therapy, first edition. Lower Extremity Review, LLC, 2011. 3. Kogler GF, Veer FB, Solomonidis SE, Paul JP. The influence of medial and lateral placement of orthotic wedges on loading of the plantar aponeurosis. An in vitro study. J Bone Joint Surg Am. 1999;81(10):1403-13. 4. Scherer PR. Four peer reviewed articles the every podiatrist should read. Podiatry Management. September 2011, 119-126. 5. Kogler GF. Biomechanics of Longitudinal arch support mechanisms in foot orthoses and their effect on plantar aponeurosis strain. Clin Biomech. 1996; 11(5):243-52. 6. Scherer PR. Heel spur syndrome. Pathomechanics and nonsurgical treatment. Biomechanics Graduate Research Group for 1988. J Am Podiatr Med Assoc. 1991;81(2):68-72. 7. Walther M, Kratschmer B, Verschl J, et al. Effect of different orthotic concepts as first line treatment of plantar fasciitis. Foot Ankle Surg. 2013 Jun;19(2):103-7. 8. Lee WC, Wong WY, Kung E, Leung AK. Effectiveness of adjustable dorsiflexion night splint in combination with accommodative foot orthosis on plantar fasciitis. J Rehabil Res Dev. 2012;49(10):1557-64. 9. Rosenbloom KB. Pathology-designed custom molded foot orthoses. Clin Podiatr Med Surg. 2011;28(1):171-87. 10. Kripke C. Custom vs. prefabricated orthoses for foot pain. Am Fam Physician. 2009;79(9):758-9. 11. Baldassin V, Gomes CR, Beraldo PS. Effectiveness of prefabricated and customized foot orthoses made from low-cost foam for noncomplicated plantar fasciitis: a randomized controlled trial. Arch Phys Med Rehabil. 2009;90(4):701-6. 12. Lee SY, McKeon P, Hertel J. Does the use of orthoses improve self-reported pain and function measures in patients with plantar fasciitis? A meta-analysis. Phys Ther Sport. 2009;10(1):12-8. 13. Hume P, Hopkins W, Rome K, Maulder P, Coyle G, Nigg B. Effectiveness of foot orthoses for treatment and prevention of lower limb injuries: a review. Sports Med. 2008;38(9):759-79. 14. Hawke F, Burns J, Radford JA, du Toit V. Custom-made foot orthoses for the treatment of foot pain. Cochrane Database Syst Rev. 2008 Jul 16;(3):CD006801. 15. Janisse DJ, Janisse E. Shoe modification and the use of orthoses in the treatment of foot and ankle pathology. J Am Acad Orthop Surg. 2008;16(3):152-8. 16. Roos E, Engström M, Söderberg B. Foot orthoses for the treatment of plantar fasciitis. Foot Ankle Int. 2006;27(8):606-11. 17. Flicek BF. Heel spurs and plantar fasciitis: an update on therapies. Adv Nurse Pract. 2006;14(1):61-2. 18. Landorf KB, Keenan AM, Herbert RD. Effectiveness of different types of foot orthoses for the treatment of plantar fasciitis. J Am Podiatr Med Assoc. 2004;94(6):542-9. 19. Seligman DA, Dawson DR. Customized heel pads and soft orthotics to treat heel pain and plantar fasciitis. Arch Phys Med Rehabil. 2003;84(10):1564-7. 20. Gross MT, Byers JM, Krafft JL, Lackey EJ, Melton KM. The impact of custom semirigid foot orthotics on pain and disability for individuals with plantar fasciitis. J Orthop Sports Phys Ther. 2002;32(4):149-57. 21. Martin JE, Hosch JC, Goforth WP, Murff RT, Lynch DM, Odom RD. Mechanical treatment of plantar fasciitis. A prospective study. J Am Podiatr Med Assoc. 2001;91(2):55-62. 22. Pfeffer G, Bacchetti P, Deland J, et al. Comparison of custom and prefabricated orthoses in the initial treatment of proximal plantar fasciitis. Foot Ankle Int. 1999;20(4):214-21. 23. Lynch DM, Goforth WP, Martin JE, Odom RD, Preece CK, Kotter MW. Conservative treatment of plantar fasciitis. A prospective study. J Am Podiatr Med Assoc. 1998;88(8):375-80. 24. McPoil TG, Schmit D. Comparison of three methods used to obtain a neutral plaster foot impression. Phys Ther. 1989; 69(6):448-52. 25. Roukis TS, Scherer PR, Anderson CF. Position of the first ray and motion of the first metatarsophalangeal joint. J Am Podiatr Med Assoc. 1996; 86(11):538-46. 26. McClay-Davis I, Laughton C, Williams, DS. Comparison of four methods of obtaining a negative impression of the foot. J Am Podiatr Med Assoc. 2002; 92(5):261-8.

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