This article presents a review of conservative therapies for plantar fasciitis pain reduction with a discussion of steroid therapy risks. These modes were included based on the availability of double blinded randomized controlled trials. We noted the following findings. Orthoses, regardless of type, can improve pain levels. Extracorporeal shockwave therapy shows equivocal benefit with some studies showing significant improvement and others showing none. Although BTX-A injections were the least studied, significant pain improvement was demonstrated in the short and long term.
Steroid therapy, when coupled with plantar stretching, can provide efficacious pain relief; however, steroid injections should be combined with ultrasound monitoring to reduce complications. Plantar fasciitis is a common foot disorder responsible for approximately one million physician visits per year [ 1 ].
While there are a plethora of management techniques for plantar fasciitis, there are none that are presented as a definitive technique. In addition, the etiology of plantar fasciitis is not well understood [ 2 ]. Accordingly, this article will focus on a variety of conservative therapies with a follow-up focus on steroid injections and the risks thereof. The plantar fascia is synonymous with the deep fascia of the sole of the foot. The plantar fascia is comprised of pearly white longitudinally organized fibers. It begins at the medial tuberosity of the calcaneus where it is thinner and extends into a thicker center portion.
This thicker portion is flanked by thinner lateral and medial portions. The thicker central portion of the plantar fascia then extends into five bands surrounding the digital tendons Fig. From Buchbinder [ 4 ]. Used with permission from NEJM.
Plantar and medial views of the foot demonstrating the origin and insertion of the plantar fascia and the location of nerves in proximity to the heel. The windlass mechanism, or bowstring effect, of the plantar fascia refers to its function in raising the arch of the foot during the push-off phase of walking.
Hicks described a windlass mechanism of action for the plantar fascia. Dorsiflexion of the toes leads to a shortened effective length of the plantar fascia causing a raising of the arch. Toe extension leads to increased arch tension with the metatarsophalangeal joint as the pivot or tethering point. Hicks [ 5 ] demonstrated this definitively with cadaveric models. When a plantar fasciotomy was performed, the cadaver would lose this windlass mechanism, thus diminishing the arch stability subsequently disallowing a more stable terminal stance and toe standing.
In addition, Hicks [ 5 ] found that the breaking strain for this windlass ranged from 1. Thus, the plantar fascia, while playing a significant role in walking stability, can readily break with a minimal increase in strain. While the exact etiology of plantar fasciitis remains unclear, it is theorized that overloading the plantar foot muscles originating at the volar calcaneus adductor hallucis, quadratus plantae, flexor digitorum brevis, and abductor digiti minimi quinti can lead to inflammation and consequent pain in the plantar fascia [ 6 ].
Hence, therapy for plantar fasciitis focuses on either reducing the muscle tightness that causes the initial injury or reducing the inflammation that worsens the injury. Plantar fasciitis is a clinical diagnosis. It is based on patient history and physical exam. Plantar fascia pain is especially evident upon dorsiflexion of the patients pedal phalanges, which further stretches the plantar fascia or windlass mechanism.
Therefore, any activity that would increase stretch of the plantar fascia, such as walking barefoot without any arch support, climbing stairs, or toe walking, can worsen the pain [ 4 , 7 ]. A Medline search from to the present was performed. Trials were included if they were randomized studies and evaluated orthoses, stretching, extracorporeal shockwave, BTX-A, or corticosteroid injection as therapies for plantar fasciitis. Trials were excluded if they did not meet the above criteria or if they compared the efficacy of one mode of therapy to another, that is, stretching to orthoses or BTX-A to steroid therapy in plantar fasciitis.
SORT graded as per Ebell et al. Numerous treatment measures have been used for plantar fasciitis with varied clinical benefits. Nonsurgical techniques include orthoses [ 9 , 10 ], stretching [ 11 — 13 ], splinting, taping, topical medications with or without iontophoresis, oral nonsteroidal anti-inflammatory medications [ 22 ], extracorporeal shockwave therapy [ 14 — 18 ], laser, and percutaneous injections with steroid [ 20 , 21 ] or botulinum toxin type A.
Surgical options with endoscopic or open fasciotomy can be the last resort for patients with intractable plantar fasciitis [ 23 ], but are not discussed further in the article. They found that there was no statistically significant difference in improvement in subjective heel pain between different insole modes; however, there was a statistically significant improvement in both the magnetic and nonmagnetic groups in morning foot pain intensity.
DiGiovanni et al. Both Achilles stretching groups and plantar fascia stretching groups appreciated a decrease in pain upon first steps in the morning as well as increased function; however, the plantar stretchers appreciated a statistically significant improvement in activity function and first step pain as compared to the Achilles stretchers [ 11 ].
DiGiovanni further assessed the improvement of plantar fascia versus Achilles tendon stretching by directly comparing the two in a crossover study of the same patient pool with a 2-year follow up. Radford recruited 92 subjects for their study that compared calf muscle stretching with sham ultrasound to sham ultrasound alone. The study tested the short-term effectiveness of stretching.
The study pool either received ESWT or sham therapy. Over the 6-month course of the study, no statistical significance was shown between sham and ESWT groups in the above categories [ 15 ]. Kudo et al. The patients were exposed to a single treatment. Ogden et al. In the first phase, they formulated and finalized their protocol with 20 nonblinded patients.
In the phase two trial, Ogden randomized patients to receive either ESWT and an ankle block or a mild anesthetic and nontransmitted shockwaves. Significance was also found in subjective self-assessment of morning heel pain at the same time intervals. Hence, Ogden et al. Babcock et al. Either BTX-A was injected into the feet of the therapy group or saline into the sham group.
In the case of patients with bilateral plantar fasciitis, saline was injected into one foot and BTX-A in the other. Crawford et al. There was no statistically significant difference in pain levels when prednisolone was given with tibial block or when anesthetic was given. Hence, Crawford et al. Gudeman assessed the efficacy of steroid iontophoresis in 40 feet 37 subjects. Feet were divided equally into a group that received phosphate buffered solution iontophoresis and one that received dexamethasone iontophoresis.
The Maryland foot score was used to analyze the groups. The active group showed significantly greater improvement immediately after treatment. Ultimately, Gudeman et al. As evidenced above, multiple modes of therapy can lead to pain reduction in plantar fasciitis. When more conservative management is unsuccessful, steroid injection is a preferred option [ 28 — 30 ].
Although steroid injection is the mainstay for the management of many hyper inflammatory disorders, there is little known about steroid affect at the cellular level and, consequently, little about the etiology of the risks of connective tissue rupture after the same [ 31 ].
Cystic spaces and collagen necrosis were appreciated in their steroid group. However, at 2 and 4 weeks following injection, these cystic spaces were replaced by an eosinophillic staining material and fibroblast proliferation was noted. Disordered collagen deposition was appreciated under scanning electron microscope. In addition, the failing strength returned to that of the control subjects. Hence, Kennedy and Willis concluded that physiologic dosed steroid injection weakens normal tendons for up to 14 days through collagen necrosis.
They also recommend limited physical activity for the 2 weeks following injection and against repeated injection [ 24 ]. Furthermore, Wong et al. Proteoglycan synthesis has a role in extracellular matrix and collagen matrix fibrillinogenesis.
Wong et al. While steroid injection and iontophoresis can significantly improve foot pain in plantar fasciitis, the two methods warrant further investigation. As evidenced by Crawford and Gudeman, steroid therapy in plantar fasciitis plays a significant role in short-term therapy [ 20 , 21 ]. However, a number of complications were noted including plantar fascial rupture, plantar fat pad atrophy, lateral plantar nerve injury secondary to injection, and calcaneal osteomyelitis and in iontophoresis, burning of the underlying skin [ 21 , 34 — 39 ].
Fascial rupture and fat pad atrophy are especially serious complications as they can lead to intractable complications. Fascial rupture interrupts the intrinsic windlass mechanism of the foot and can promote further inflammation in the surrounding tissue, thus promoting pain.
In addition, plantar fat pad atrophy diminishes subcalcaneal cushioning, availing the plantar fascia to further insult and, hence, more pain. Acevedo et al. All of the ruptured patients presented with new additional symptoms including long arch pain, lateral mid foot pain, and an exam showing decreased windlass tension [ 35 ].
Treatment of plantar fasciitis rupture remains unclear. Treatment options for the rupture are open surgical repair, endoscopic repair, and nonoperative measures. Sellman and Acevedo et al. Daly et al. Because of the recent availability and facility of ultrasound US to improve needle placement accuracy and confirmatory magnetic resonance imaging MRI in clinical practice, enhanced therapeutic response rates have been reflected in some of the studies [ 29 , 30 , 35 , 41 ]. Tsai et al. In addition, following single US-guided steroid injection, fat pad atrophy, which was theorized to cause worsening pedal dynamics, was not observed [ 30 ].
Heel fat pad inflammation and degeneration may cause pain and can be misdiagnosed as plantar fasciitis [ 42 ]. Further, MRI or US can be used to make appropriate diagnoses, which is particularly important for patients with chronic polyarthritis. Nevertheless, these complications are uncommon and preventable; rupture may occur without steroid injections [ 35 ]. Paying special attention to history and physical examination change can lend some clues to associated complications.
Monitoring sudden pain loss, change of patient pain location, developing numbness, changes in plantar fascial and fat pad thickness, edema, palpable masses, asymmetric flexible hammertoe deformities of the 2nd, 3rd, and 4th toes without nerve injury, and utilizing US for follow ups and injection placement can help to alleviate negative outcomes.
Further, limiting the number and frequency of steroid injections and educating patients on reduction of aggressive physical activity during a 2-week post-injection period should be suggested [ 35 ].