Ensuring Patients Get A Perfect Orthotic Fit

These expert panelists discuss checking the construction of orthoses and their fit in shoes to ensure optimal use of orthoses. They also offer pearls on what to look for if there is not a good fit with orthoses.

Q:

What biomechanical assessments do you perform before casting for an orthosis?

A:

For Stanley Beekman, DPM, part of the biomechanical exam includes asking questions to determine the history of the pain. He says the pattern of symptoms should point to equinus, asymmetry, pronation or lack thereof. For instance, Dr. Beekman says a chronic, painful, unilateral Achilles tendon on one side suggests a short leg while a bilateral case suggests bilateral equinus. If the pain occurs just as the heel comes off the ground, this points to a functional hallux limitus, according to Dr. Beekman.

Dr. Beekman’s physical exam consists of the following:
• dorsiflexion of the ankle (to help determine the need for a heel lift);
• dorsiflexion of the first metatarsophalangeal joint (MPJ) loaded and unloaded (to help determine the need for a second to fifth sub-metatarsal raise);
• measuring the anterior superior iliac spine (ASIS) and the posterior superior iliac spine (PSIS) to the ground (to determine if a one-sided heel lift is required); and
• measuring neutral and relaxed calcaneal stance position (to determine if a rearfoot and/or forefoot post are needed).

Karen Langone, DPM, starts with evaluating range of motion, beginning at the distal aspect of all lower extremity joints and subsequently assessing muscle strength. She then assesses the patient’s stance position, from head to feet and from anterior, posterior and the side in order to evaluate for the position of the joints, alignment and symmetry. Dr. Langone will assess for limb length and then has the patient perform the single leg balance test with his or her eyes closed. Then she will have patients do the single leg squat test.

Adam Spector, DPM, performs a static/non-weightbearing exam as well as a weightbearing/standing exam. When possible, he evaluates patients’ walking as well as their running gait. Dr. Langone also performs a video gait analysis and reviews it in slow motion. If the patient is an athlete, she also does this with the patient running. She uses the F-Scan In-Shoe Analysis System (Tekscan).

“My goal is to obtain as much information on the patient’s movement patterns as I possibly can,” says Dr. Langone.

Dr. Spector also evaluates limb length discrepancies, stride length, cadence, posture, pressure points and the weight of the patient. Then he tries to correlate those findings with the symptomatology and the medical/injury history of patients to devise an orthotic that will best meet their needs and improve their condition.

Dr. Beekman agrees that one should correlate the exam with the patient history. For instance, he notes chronic asymmetrical plantar fasciitis should correlate with an asymmetrical equinus, asymmetrical foot and/or leg structure, a unilateral hallux limitus or asymmetric pronation.

Q:

In a new orthotic, what do you evaluate to ensure patients will receive an appropriate fit?

A:

The first step is placing the orthosis against the patient’s foot, advises Dr. Beekman. He says one should make sure the heel does not override the heel cup, the arch is conforming to the patient’s foot and the length and distal shaping of the orthosis are correct.

Dr. Langone uses digital scanning to capture the images of the foot and evaluates those for accuracy. Upon dispensing of the orthotic, she confirms the prescription and evaluates the fit of the orthotic to the foot. Dr. Spector also matches the orthotic up with the patient’s foot and ensures the device fits well in the shoe. He also wants to see patients stand and walk in the new orthotics to see whether the devices are accomplishing their goal.

“If the lab followed my prescription precisely and utilized our old-school, more reliable plaster cast properly, then the orthotic should fit, feel and function well,” says Dr. Spector.

To evaluate each part of the orthosis, Dr. Beekman notes the heel cup has to have the correct depth. As he explains, deeper heel cups will extend further backward, thereby pushing the foot forward in the shoe and contributing to the heel “popping” out when the patient walks. Conversely, Dr. Beekman notes shallow heel cups may not come to the edge of the shoe and can create an edge effect or decrease the effectiveness of the orthosis.

The medial arch region of bulk orthoses should be undercut to fit the shoe properly, advises Dr. Beekman. If not, he says the patient cannot tighten the laces effectively, which can contribute to the heel “popping out.”

The front edge of the rigid part of the orthosis should follow the parabola of the metatarsals, according to Dr. Beekman. (However, he notes that in cases in which patients require stability at push-off, the front edge should be a straight line following the first to fifth metatarsal heads.) If the lateral part of the forward edge extends too far distally, he says there will be additional pressure under the fifth and possibly the fourth metatarsal head at midstance and especially at propulsion.

Finally, Dr. Beekman says one should place the orthosis in the shoe, making sure that it fits and does not wobble in the shoe. He adds that in a bulk orthosis, one should grind the plantar aspect of the orthosis at the fulcrum of the wobble. If there is a wobble over the shank of the shoe, Dr. Beekman suggests carefully heating the device in the medial and lateral arch area only, and bending the orthosis to fit the shoe.   

Q:

How do you evaluate shoes to ensure patients receive a good fit?

A:

Dr. Spector has in-depth discussions with patients about what shoes they are wearing or which ones they should be wearing before making the orthotics.

“A common reason for orthotics not being effective is not fully considering how they will fit and function in our patient’s shoes,” says Dr. Spector. “Communication with the lab is also vital and it is sometimes necessary to send photos of the patient’s foot or shoes, or even send the shoes themselves to meet this goal.”

First, Dr. Beekman advises making sure the size is correct. He also suggests checking for length by feeling for the end of the hallux (in a full-length orthosis) and checking the width by looking at the exposed width of the tongue.

The heel counter, Dr. Beekman notes, should be deep enough to allow for any change of the position of the heel due to the thickness of the rearfoot of the orthosis. He adds that the upper should have a lace closure and a slip-on shoe uses elastic to keep the foot in the shoe. If the orthosis has some thickness to it, Dr. Beekman notes the elastic increases its pressure as it stretches as opposed to laces that can accommodate an orthotic with no increase in pressure. He also says a lace enclosure is preferable in a slip-on shoe.

Dr. Beekman notes the toe box has to have enough volume to accommodate a full-length orthosis. The best shoe for the full-length orthosis has a removable insole, which one can replace with the orthosis.

Dr. Langone educates patients on shoe fit and also refers to pedorthists to ensure a correct fit. She tells patients to buy shoes at the end of the day and that the shoes should have a thumb’s width in available space from the end of the toes to the end of the shoe with the widest part of the foot corresponding to the widest part of the shoe.

The preferable type of men’s dress shoe is a Blucher shoe as opposed to a Blount shoe, according to Dr. Beekman, as the Blucher provides for more adjustability in the dorsal area of the metatarsal heads. Additionally, he says the outsole should be flexible. Excessive stiffness at propulsion will prevent the heel from rising with the foot, contributing to the heel “popping out,” according to Dr. Beekman.

Q:

What should you be looking for when a patient feels that the orthotic is not functioning correctly?

A:

“Not to sound blasphemous but custom orthotics are not for everybody,” contends Dr. Spector. “Sometimes OTC arch supports are more appropriate or more comfortable.”

If he feels everything has happened correctly regarding the orthotic process and the patient still has problems, Dr. Spector often considers other approaches or strategies to address their issues. This may include physical therapy, medication, alternate bracing systems, or gait/running training modifications. He says these modalities may be necessary adjuncts to orthotics.

Dr. Beekman turns the orthotic upside down and makes sure the plantar aspect of both posts are parallel. He says one should have the patient stand barefoot, draw a line perpendicular to the ground on the posterior calcaneus and then have the patient stand on the orthoses without the shoes. The bisection should invert with the patient standing on the orthoses if one is trying to decrease pronation, suggests Dr. Beekman. While the patient is standing on the orthoses, he says one should make sure the patient is not sliding laterally off the heel of the orthoses. Dr. Beekman notes this abduction of the midfoot is pronation around the oblique axis of the midtarsal joint.

Initially, Dr. Langone determines if the patient properly broke in the devices. She looks to see if there is a shoe/orthotic incompatibility and also examines the orthotic for shape and contour relative to the foot. Dr. Langone checks the orthotic prescription and then reviews the biomechanical and motion analysis data. She also performs another F-Scan test with the orthotic, which usually allows her to determine where the problem lies.

Dr. Beekman also says one should check the patient, recheck ankle dorsiflexion and add a heel lift accordingly. He checks the levelness of the anterior superior iliac spine and the levelness of the posterior superior iliac spine with the patient standing on the orthoses and again standing on the floor without the orthoses. The clinician should check for functional hallux limitus and that the thickness of the second to fifth metatarsal posts corresponds to the amount required to reestablish resistance-free first MPJ range of motion, according to Dr. Beekman.

Finally, Dr. Beekman advises checking the shoes, looking at the counter of the shoe to see if there is lateral stability to prevent the foot from sliding in the shoe. Then he notes one should make sure the counter is perpendicular to the outsole so there is no wedging effect from the shoe. 

Dr. Beekman is a Diplomate of the American Board of Podiatric Surgery. He is also a Fellow of the American Academy of Podiatric Sports Medicine.

Dr. Langone is a Fellow of the American College of Foot and Ankle Orthopedics and Medicine, and the Treasurer of the American Association for Women Podiatrists. She is a Fellow and Past President of the American Academy of Podiatric Sports Medicine. She is in private practice in Southampton, NY.

Dr. Spector conducts bimonthly multispecialty running clinics. He is board certified by the American Board of Podiatric Surgery, and is a Fellow of the American Society of Podiatric Surgeons. Dr. Spector is in private practice in Maryland.

For further reading, see “Keys To Assessing Orthotic Function” in the September 2015 issue of Podiatry Today, “Current Insights On Prescribing AFOs” in the December 2014 issue or “Current Insights On The Benefits Of Custom Orthoses And AFOs” in the February 2014 issue.

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