Current Insights On Orthoses For Achilles Tendinosis, Plantar Fasciitis And Posterior Insertional Spurs
“I am not sure how orthoses work for this condition but they do,” notes Dr. Richie. He says we can assume that the devices are reducing frontal plane motion of the calcaneus and therefore reducing the load of the Achilles at the insertion site. He also wonders if the heel cup of the device changes the shoe dynamics to reduce friction or pressure on the posterior calcaneus.
“Either way, foot orthotic therapy for insertional calcaneal spurs can be helpful for the athletic patient who wears closed shoes most of the time,” maintains Dr. Richie.
For Dr. Clough, orthotics are a mainstay when treating posterior insertional calcaneal spurs. As he explains, this condition develops mainly due to excessive tension of the Achilles tendon in propulsion from a lack of ankle joint plantarflexion. The pull of the Achilles on the posterior heel becomes eccentric rather than concentric, which he says results from a lack of motion of the first MPJ, comparing it to his aforementioned scissor jack analogy. Furthermore, Dr. Clough says a lack of motion of the first MPJ results in lack of motion of the ankle, knee, hip and lower back. The tension of the Achilles pulls against the heel that will not rise properly and he says this will result in a spur at the retrocalcaneal area.
Dr. Clough will often use a P4 Wedge with an OTC device initially to improve motion of the first MPJ. If this is not effective, he uses a custom device. To correct this problem with plantarflexion of the first metatarsal, he suggests using minimal orthotic fill. In addition, Dr. Clough corrects any forefoot valgus by plantarflexing the fourth and fifth metatarsals and adds minimal fill in the lateral arch just as he would do medially. He uses a P4 wedge in all of these cases.
“Very often, you also need to spend a few moments with your patients to get them to start to roll through the first MPJ and take a longer stride and walk faster without shuffling,” says Dr. Clough. “Very few of these problems require surgery at the initial stage but if large spurs have developed, they become a source of injury to the tendon fiber and conservative care, in this case, is much less effective.”
Dr. Richie recommends a deep heel cup (16 to 22 mm) and adds a ¼-inch heel lift to a rearfoot post, which is inverted 2 degrees with 2 degrees of motion. For the non-athletic patient, particularly a female, he prefers prescribing an open, elevated clog style shoe and forgoes the orthotic.
Have you had success in using orthoses for patients with plantar fasciitis?
Dr. Williams uses ethylene vinyl acetate (EVA) orthoses for the majority of his patients with plantar fasciitis. For patients who are extremely overweight and/or have extremely flat flexible feet, he uses polypropylene, noting that EVA often will not support the load effectively.
In addition, Dr. Williams uses a Cluffy type digital skive (Cluffy Institute) under toes one through five in most patients with plantar fasciitis to preload the plantar fascia, especially the medial band. He says this makes the toe less likely to plantarflex in late midstance. Dr. Williams will utilize a 3 mm heel lift bilaterally in patients with limited Achilles dorsiflexion or an equinus type deformity. This decreases the load on the Achilles and he notes that an overloaded Achilles can cause peroneal dysfunction, which in turn can lead to functional hallux limitus issues.
Dr. Clough typically sees a 70 percent decrease in pain in about three weeks with plantar fascia stretches, ice and insoles. With insoles, OTC devices are his preferred choice unless there is significant rearfoot eversion. He uses a P4 Wedge to control the first ray and allow the foot to transition from a loosely packed position at heel contact to a closed packed position at toe off.