Conservative care is a mainstay for the large population of patients with proximal plantar fasciitis. Accordingly, this author takes a critical look at the research on conservative treatments such as stretching, injections and orthoses with an emphasis on addressing underlying biomechanical factors.
In his final published text in 2012, Sglarato discussed the epidemic of heel pain occurring in the United States.1 In contrast, Sglarato noted that when he wrote the Compendium of Podiatric Biomechanics in 1971, heel pain was not that common so he only devoted a few short sentences to it.2
Sgarlato, as well as a number of his colleagues, believed this incidence of heel pain was possibly due to the softer, less stable footwear that patients wear while walking or running on flat, firm unyielding surfaces.2 This is in contrast to the steel shank, rigid counter footwear that was de rigueur back in the day.
Plantar fasciitis currently affects 15 percent of the general population and is the presenting complaint in 11 to 15 percent of all foot disorders for which patients seek professional care.3-6 At least 1 million people in the U.S. receive treatment for this condition annually.7
No matter which therapeutic combination one selects for initial management, one must identify and neutralize the underlying predisposing, perpetuating or aggravating biomechanical abnormality in order to improve function, reduce pain, promote healing and prevent recurrence. Resolution of symptoms without addressing these deficiencies may create secondary pathologic or “trade-off” segments of lower extremity dysfunction.
Look online and what do you see recommended or as part of every management regimen for proximal plantar fasciitis? Stretching. Patients can purchase a slant board, do eccentric heel drops off a stair or buy a set of bands to stretch the calf and plantar fascia before they get out of bed each morning. However, none of this is addressing the underlying issue, which is why the plantar fascia is stretching beyond its physiologic limits in the first place. Stretching the plantar fascia provides only temporary relief by lengthening the fascia enough to be able to accept the abnormal forces directed through it.
Stretching the calf musculature in reality also stretches the plantar fascia since as the Achilles tendon wraps around the calcaneus, it functions as the plantar fascia so stretching the Achilles also stretches the plantar fascia. Dorsiflexing the hallux stretches the plantar fascia as well.
It never seemed to make sense to be stretching an injured area in an attempt to make it longer to accommodate pathologic forces that have caused it to become inflamed. Yes, stretching does make the patient feel better but only by lengthening the fascia (essentially tearing additional microfibers) to accommodate the deforming forces imposed upon it. So in six months, the patient comes back with the same complaint or may even have it on the opposite heel, and what we often advise is more stretching, ice, therapy, etc.
Another issue with this approach is that the plantar fascia is not a tendon but is essentially ligamentous in nature. Since ligaments are expansile, not contractile, overstretching of the plantar fascia will prevent it from returning to its original degree of contractility.
In a study of 160 patients with proximal plantar fasciitis, 71 patients performed standing stretches and 89 wore night splints.9 The results revealed 59 days for recovery with stretching and 18 days with the night splint. Two meta-analysis studies on the effect of stretching in the treatment of proximal plantar fasciitis showed no statistically significant improvement in favor of the intervention group.9,10
Assessing A Patient’s Fitness-Related Activities
Along with evaluation of footwear, the evaluation and assessment of all fitness-related activities is essential for successful management outcomes for proximal plantar fasciitis. One should determine what activities patients are engaging in and whether they are wearing the proper footwear for each activity. In general, I have patients avoid activities that place undue strain on the plantar fascia. These activities include court sports, barefoot walking, barefoot and shod running, treadmill training and bouncing, jumping, twisting, strengthening or lengthening exercises, etc.
When it comes to proximal plantar fasciitis, acceptable fitness activities include swimming and biking (no standing on forefoot). While patients can usually tolerate elliptical trainers, these devices can irritate the plantar fascia. It really depends on their speed and how far back patients bring their limb. Performing StairMaster exercise with a midfoot strike is another activity that patients can try. Swimming is usually not a problem unless there’s an aggressive push off with each lap. Certain yoga poses put increased strain on the plantar fascia due to hyperextension of the metatarsophalangeal articulations during plank exercises and forced ankle dorsiflexion in the downward dog pose.
As far as treadmills and proximal plantar fasciitis are concerned, I have patients discontinue their use at least until they can walk 15 minutes briskly over ground and there is no pain upon arising from bed. Individuals tend to walk faster on treadmills, their cadence is greater, there is increased hip extension, decreased knee extension and decreased stride length.11
However, the most important difference when walking on a treadmill is that gait is externally driven by the treadmill, not internally driven by the individual. During treadmill walking, the foot is not “pushing off” to initiate swing phase but rather lifting up to keep up with the treadmill belt and prevent falling. This adaptation results in a spinal-generated mechanism rather than the normal central pattern pathway that occurs from visuomotor coordination with cortical modulation when one is walking over ground.12,13
This pulls the stance limb farther backward under the trunk, which is gliding forward under the stance limb. Movement of the ground slipping backward under the foot increases dorsiflexion at the first metatarsophalangeal articulation, thus increasing plantar fascial strain. Increasing treadmill speed and/or incline accentuates this issue. Increasing the treadmill incline accentuates any pronatory forces into the foot and since the limb is pulling back further than over ground, it stretches the Achilles tendon, which in turn introduces additional pathologic, sagittal plane plantar fascial stresses.
In general, for a 5’8” patient with proximal plantar fasciitis, I suggest walking speeds of not more than 3.2 mph without any incline once patients are asymptomatic. For walking speeds over 3.2 to 3.5 mph, I recommend a slow jog.
A Closer Look At The Potential Of Neurostimulation
The analgesic effects of noninvasive neurostimulation, a relatively new form of electrotherapy, have recently shown positive results in the treatment of musculoskeletal disorders.14 This treatment selectively stimulates nerve fibers A, delta and C.15 This differs from transcutaneous electrical nerve stimulation (TENS) by its distinctive electrode positioning and greater amplitude and density of applied current.15,16 The anti-inflammatory effects and interactive nature of the noninvasive neurostimulation with diagnostic feedback regarding skin impedance makes it suitable for use in areas of chronic tissue degeneration such as proximal plantar fasciitis.17
A recent study of 104 patients revealed a patient satisfaction rate of more than 90 percent in the noninvasive neurostimulation group and a 36.7 percent satisfaction rating in the extracorporeal shockwave group.17 The authors conclude that although both treatments are effective, the noninvasive neurostimulation modality was superior.
How Effective Are Steroid Injections In The Plantar Fascia?
Researchers have shown that steroid injections are effective in the short-term but not in the long-term management of proximal plantar fasciitis.18 The authors of a systematic review of 39 studies involving 2,942 adults with proximal plantar fasciitis concluded that there is low quality evidence that steroid injections may slightly reduce heel pain for up to one month but not thereafter.19
With that being said, for the acute management of proximal plantar fasciitis, steroid injections do provide relief and disrupt the pain cycle. Local injection consists of 2 mg dexamethasone PO4 and Marcaine 2.5 mg with or without epinephrine. (This is one injection in the same syringe, either with a medial tubercle 5/8-inch needle or an inferior tubercle 1-inch needle.) These injections are safe, time-tested, clinically proven and effective approaches for the initial management of moderate to severe pain associated with proximal plantar fasciitis.
One may repeat this steroid injection each week for several weeks if necessary with no loss of fat pad atrophy. Consider a slightly longer acting steroid such as betamethasone acetate and betamethasone PO4 if progress is not as rapid as you would expect. Even though triamcinolone acetonide 20 to 40 mg is an effective and first choice steroid for many podiatrists and orthopedists, I reserve it for recalcitrant cases that have been unresponsive to the more soluble steroid formulations.20,21 Due to significant fat pad and surrounding soft tissue atrophy coupled with the increased risk of plantar fascial rupture, the use of long-acting steroids in the management of proximal plantar fasciitis has traditionally been limited to a maximum of three injections per year.22
What Is The Verdict On Other Injection Options?
Other recent injection options include dry needling or percutaneous fenestration, platelet rich plasma (PRP), prolotherapy (such as hyperosmolar dextrose) and botulinum toxin A (Botox, Allergan). Platelet-rich plasma injections are not as effective as steroid injections.19,22 Researchers found that prolotherapy with a 25 percent dextrose/lidocaine solution is effective in reducing proximal plantar fasciitis pain.23 In a study by Placzyk and colleagues, botulinum injection reduced proximal plantar fasciitis pain for up to 14 weeks.24 Babcock and coworkers also deemed botulinum effective for proximal plantar fasciitis.25
A recent study by Gogna and colleagues compared PRP injections with low dose radiation therapy in 40 patients with chronic proximal plantar fasciitis.26 The results indicated that PRP is as good as low dose radiation therapy for reducing pain and decreasing fascial band thickness in chronic cases of proximal plantar fasciitis.
Addressing Mechanical Dysfunction Through Orthoses
No matter what type of injection or therapy you use to reduce inflammation and relieve pain in patients with proximal plantar fasciitis, the underlying mechanical dysfunction of the foot that has caused this condition remains the same. Therefore, one needs to take steps to improve foot function. This can initially happen via splints, strapping, shoe recommendations and modifications, prefabricated devices, heel raises, appropriate stretching and strengthening exercises, and subsequently through custom foot orthoses.
In general, most studies find custom orthoses to be beneficial in the management of proximal plantar fasciitis although some studies have shown conflicting results.10,27–30 In a study of 15 patients with proximal plantar fasciitis for an average of 21 months, there was a 75 percent reduction of disability and 66 percent reduction of pain with semi-rigid foot orthoses.31 According to recent studies, both prefabricated and custom foot orthoses reduced pain and improved foot function in patients with proximal plantar fasciitis.32,33 Another study did not reveal superiority of custom devices over prefabricated devices but did acknowledge their effectiveness in relieving heel pain when one uses them in conjunction with a night splint.34
Kogler’s cadaveric plantar fascia tension study indicated a Root orthotic from a suspension cast did not decrease plantar fascia tension as much as semi-weightbearing non-Root devices.35 Phillips examined this study more closely and cited numerous concerns regarding the materials the researchers employed, their attendant properties and the implications of plaster impression casting on cadavers.36 Additionally, how do you obtain an accurate assessment of frontal and sagittal plane deficiencies in a cadaver?
Many studies assessing orthotic effectiveness for proximal plantar fasciitis do not mention the relationship of the forefoot to the rearfoot nor do the researchers employ this relationship as part of the orthotic prescription. So for an individual who has a flexible or rigid forefoot valgus deformity, or forefoot varus deformity, how can one achieve adequate control in a custom orthosis that doesn’t incorporate the appropriate correction? Isn’t the objective of the custom device to align the rearfoot and forefoot so the arch supports itself? A properly fabricated Root type device would act as a motion guidance system, not as a support to empirically buttress the longitudinal arch.
It has been my experience as well as that of a significant number of colleagues that custom foot orthoses with appropriate modifications are indicated and a mainstay in the conservative management of proximal plantar fasciitis of mechanical origin.1,37–39 Scherer states that properly casted and fabricated custom orthoses can produce more than 80 percent relief from proximal plantar fasciitis, which in turn confirms the pathology to be primarily mechanical in nature.40
If custom foot orthoses were not effective in the conservative management of proximal plantar fasciitis, then why over the past 50-plus years have patients who have had orthoses gotten better? Maybe what we need are better, more randomized controlled studies that focus on temporal gait cycle parameters, center of force trajectories and weight distribution pathways with and without properly evaluated, prescribed and fitted custom devices.
Evaluation of outcomes is another area where existing studies have shortcomings. Resolution of symptoms is not a criterion of optimum function. It is perhaps an improvement but not the ideal. In fact, by ameliorating or reducing symptomatology, we may be doing a disservice to the patient by masking the underlying pathomechanics that have served to precipitate, perpetuate or aggravate this condition.
With their “tissue stress theory,” McPoil and Hunt believe that tissue stress is a causative factor for proximal plantar fasciitis and that the beneficial effect of foot orthoses in relieving pain and improving function is by reducing stress within injured areas of the body.41 But what caused the stress? Is it overuse, errors in training or a single traumatic event? Is it due to the repetitive, cumulative microtrauma ascribed to compensation for individually inherited structural imperfections with secondary adaptation through Davis’ Law of soft tissues in response to an overload of tissue stresses?42
We fabricate custom orthoses from an accurate impression cast of the patient’s feet with appropriate materials and posting in an effort to realign the osseous and soft tissue structures. This provides optimum alignment and function during stance and ambulation. The device should invert the rearfoot and adduct the forefoot to reduce medial calcaneal tubercle stresses.43
Since no two feet are the same from person to person, prefabricated devices are in reality arch supports and will be specific for no one. The studies of Feber and Bensen on the use of prefabricated supports in the management of proximal plantar fasciitis revealed that strain in the plantar fascia was 30 percent lower with prefab devices and did not improve even when clinicians heat-molded the device to the arch contours of the foot.44,45 However, these studies do not mention whether the foot was positioned properly in at least an improved or ideally subtalar neutral position during the remolding process.
A study by Landorf and coworkers found that neither prefabricated or custom devices were better than the sham orthoses in a long-term analysis.27 Upon closer inspection of this study, Phillips points out that the sham orthotic was fabricated over the same positive model as the prefabricated and custom devices in reality, negating its label as a “sham” device.36
Arch supports, whether custom or prefabricated, empirically buttress the longitudinal arch, randomly supinate the foot and thereby unlock the longitudinal axis of the midtarsal joint. Raising the arch height by any method, including the placement of a wad of tissues under it, shortens the distance from origin to insertion of the plantar fascia, reducing fascial strain. Arch supports also increase the weightbearing surface of the foot, spreading pathologic forces over a broader area with a resultant reduction in fascial strain and symptomatology.44,45
Additionally, prefabricated orthoses do not have any correction built into the device for structural imperfections occurring in and affecting forefoot function. This is especially true in the presence of forefoot varus and flexible forefoot valgus deformities. In addition, all prefabricated devices are the same for the left and right foot, but it’s rare to find a pair of feet that are identical right and left. In his decades of clinical experience, Richie has found custom foot orthoses “far superior” to prefabricated devices in the management of proximal plantar fasciitis.46 Scherer agrees, stating that the “anecdotal evidence is obvious in demonstrating their effectiveness in treating proximal plantar fasciitis.”38 With that being said, prefabricated devices are almost always better than no devices and one may employ them as an interim initial management aid.
Pertinent Insights On Orthotic Modifications
The prescription and utilization of rearfoot and forefoot posting should accurately reflect the clinical biomechanical examination findings. One should capture and confirm these findings in the negative suspension cast with the midtarsal joint pronated and the ankle joint dorsiflexed to resistance.
In the 1991 study by Scherer and colleagues of 85 patients with heel pain of mechanical origin, the examination of 133 symptomatic heels revealed 63 feet in forefoot valgus, 20 plantarflexed first rays, 32 feet with an everted calcaneus stance position and 18 feet with neither of these characteristics.40 As a result, 86 percent of the deformities examined required longitudinal axis midtarsal joint compensation, which the study authors appropriately remedied through the addition of a valgus forefoot post or a neutralizing metatarsal bar for the second through fifth metatarsals. Furthermore, the authors stated that a valgus heel or valgus forefoot is the primary biomechanical etiology for mechanically induced heel pain.
A 1999 study revealed that placement of a wedge under the lateral aspect of the foot (valgus wedge) decreased strain on the plantar aponeurosis while wedge placement under the medial aspect of the foot (varus wedge) increased strain on the plantar fascia.35 Furthermore, wedge placement in the rearfoot did not appreciably affect strain on the plantar aponeurosis. In contrast, with calcaneal eversion, the axes are parallel, unlocking the midtarsal joint and inverting the forefoot against the rearfoot at the longitudinal axis.
All of this is fine and good when you have a foot with a forefoot valgus deformity. However, the addition of a valgus forefoot post to a foot that does not have a valgus deformity, or more likely has a varus deformity, is a horse of another color. The cause of an everted calcaneal stance position in the frontal plane can be due to a flexible forefoot valgus or compensated forefoot varus/supinatus deformity. Add to this the fact that due to ontogenic and phylogenic influences, it is forefoot varus that is the most commonly occurring structural imperfection or atavistic trait present in the human foot, and the most frequently prescribed forefoot correction no matter what the diagnosis.47–49 One cannot justify the addition of a valgus forefoot post in individuals with a forefoot varus deformity even with a diagnosis of proximal plantar fasciitis.
As far as orthotic shell materials are concerned, for the most part, a rigid to semi-rigid non-deforming shell of appropriate thickness based on weight, flexibility, equinus influences, intended use and other factors works well for most patients with proximal plantar fasciitis. Materials include but are not limited to graphite and graphite composites, polypropylene, Ortholon and even acrylics. These devices should have the necessary rearfoot and forefoot posting to encourage and enable timely resupination for propulsive stability. I recommend a 4-degree medial grind off for individuals with greater than 4 degrees of calcaneal eversion in stance and a 2 degree medial grind off in those patients with less than 4 degrees of calcaneal stance eversion.50
Materials such as leather, laminates, foams and rubbers are flexible devices that typically do not maintain their original shape and corrective alignment with use. Devices fabricated from these materials tend to deform as they wear according to the forces imposed upon them. In the case of equinus influences, patients may not tolerate a rigid to semi-rigid shell and they may need a more “forgiving,” flexible, non-deforming shell capable of allowing some sagittal plane compensation.
Orthotic modifications for proximal plantar fasciitis include a deepened heel seat, a cushioned and/or “punched out” heel seat, appropriate forefoot posting, and an optional plantar fascia groove for those cases with a tender, thickened medial fascial band.
Schuster once told me that the heel seat of an orthotic for someone with heel pain can never be too deep with ¾ to 1-inch (20 to 25 mm) being an average effective range.39 Additionally, for heel pain in athletes and because of the increased “on forefoot” presence during sports and fitness activities, Schuster was the first to recommend and routinely employ extension of forefoot posting to the sulcus, improving orthotic control and effectiveness by reducing propulsive phase fascial strain.49
Cushioning the heel seat of the orthotic may provide a more comfortable device but one should use this judiciously since dampening shock at heel contact increases the energy required to move forward. Additionally, a cushion that is too thick or too soft increases pronatory compensation by destabilization of the heel segment. In a rigid cavus foot, this may be the desired goal but in a flexible, excessively pronated foot, the increased cushioning would be contraindicated.
Raising the heel of the orthotic diminishes the degree of dorsiflexion needed for the body to pass over the supporting foot. Each ¼-inch is the equivalent of approximately 4 degrees of additional dorsiflexion that one now obtains from the new “plantarflexed” position. Since equinus compensation is one of if not the most destructive compensatory forces into the foot, negating the need for excessive subtalar or oblique axis midtarsal joint compensation is a requisite for lasting success.
Heel raises also limit the time the heel spends in contact with the ground and decreases the heel contact phase of gait, limiting ground reaction forces. Up to a certain point, elevating the heel reduces the impact at heel contact by shifting pressure to the forefoot. One may build heel raises into the orthotic itself or add heel raises in the shoe under the orthotic to act as an elevated platform upon which the orthotic rests. I personally prefer this method. This allows one to easily remove the lift when it is no longer necessary. Use any heel elevation bilaterally and not only on the symptomatic side unless there is an accompanying limb length discrepancy.
Essential Considerations With Footwear
The orthotic is only as good as its connection to the ground. A properly prescribed shoe can enhance orthotic alignment and function, and an improperly prescribed shoe diminishes it.
Similar to how they view cushioned insoles and gel heel pads, patients buy shoes because they are comfortable. Soft surfaces are not good for proximal plantar fasciitis. If you can easily press your thumb into the sole or heel of the shoe, it is too soft.
Shoe flexibility is another characteristic that can promote or prolong healing. The shoe must be able to flex at the metatarsophalangeal articulations. If you cannot flex the shoe easily in your hands, it is too stiff. The body must be able to freely pass over the supporting foot without obstacles. In the absence of sagittal plane deficiencies such as equinus and hallux limitus that may significantly increase fascial strain, it is the shoe that can be a perpetual pathology perpetrator. A shoe that has too much of a stiff sole will cause increased plantar fascial strain as the metatarsophalangeal articulations have difficulty dorsiflexing at heel-off. Schuster used to make horizontal slits with a hacksaw in the soles of runner shoes that were too stiff in order to treat not only proximal plantar fasciitis but Achilles tendinitis, gastroc and/or soleus myositis, medial tibial stress syndromes, neuromas, metatarsalgia, etc.
Another undesirable characteristic of footwear that will have a negative impact on proximal plantar fasciitis symptom resolution is midfoot flexibility. Shoes that bend easily in this region, such as minimalist footwear, allow and promote midfoot collapse by encouraging oblique midtarsal joint axis and sagittal plane equinus compensation, increasing propulsive phase pronation in susceptible individuals. Not only is there sagittal plane pathologic stretching of the plantar fascia, there are the destructive frontal plane rotary forces that accompany it. This results in a pathologic torque on the plantar fascia, magnifying the pathology. It is a lot like wetting a towel at the beach and then twisting and snapping it. This happens to the plantar fascia with each and every step in minimalist footwear.
Shoes with an elevated heel height referred to as heel drop are preferable for proximal plantar fasciitis. I recommend a 10 to 12 mm heel drop or more. The heel drop is the difference between the heel height and sole width. The higher the heel drop, the more relative ankle dorsiflexion that is available, lessening compensatory equinus influences and reducing stress and strain on the plantar fascia. For the most part, maximalist footwear has reduced heel drops and its cushiony outsoles make these shoes undesirable for use in patients with proximal plantar fasciitis.50
I agree with DeHeer that proximal plantar fasciitis is a multifactorial condition and no single treatment method will be consistently effective for every patient.51 In consideration of this fact, the more thorough the history taking, the more comprehensive the examination, and the more deficiencies one identifies and addresses, the more thoughtful the management of this condition and the more successful the outcome.
What I have presented may not be in agreement or coincide with your particular management philosophy, or be the popular viewpoint. However, it has worked for me over the years so I encourage you to give it a try.
Dr. D’Amico is a Professor and Former Chair of the Division of Orthopedic Sciences at the New York College of Podiatric Medicine. He is a Diplomate of the American Board of Podiatric Medicine, and a Fellow of the American College of Foot and Ankle Orthopedics and Medicine. Dr. D’Amico is also a Fellow of the American Academy of Podiatric Sports Medicine and a Fellow Emeritus of the National Academies of Practice. Dr. D’Amico is in private practice in New York City.
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