Although PTTD develops over time, the actual rupture will show pathological signs, said Paul A. Chromey, DPM, CPed, pedorthic educator, anatomy instructor in pedorthics at Temple University School of Podiatric Medicine in Philadelphia, and owner/operator of Northeast Pedorthic Services.
When the tendon ruptures, the talus bone plantarflexes, adducts and moves anteriorly, collapsing the longitudinal arch.
“This places tremendous tension on the spring ligament,” he
The tension then causes the joint to abduct and the calcaneus bone to evert, resulting in a flatfoot.
It is rare, however, to have an actual spontaneous rupture on the tibialis posterior muscle, Chromey
All images reprinted with permission of Paul A. Chromey, DPM, CPed.
By the time patients enter stage three, they already have experienced considerable deformity and weakness in their feet, accompanied by significant pain, explained Erick Janisse, CO
, CPed, vice president of National Pedorthic Services Inc.
in St. Louis.
According to Chromey
, patients in this classification will have a rigid flatfoot on the hindfoot.
Radiographs in this stage show arthritic changes in the tarsal joints.
Stage 4 of PTTD — which is now severe flatfoot — signals the dysfunction’s end stage.
Radiographs reveal a complete valgus collapse of the talus bone, Chromey
said, possibly resulting in necrotic ulcerations along that mid-arch collapse.
– Paul A. Chromey, DPM, CPed, pedorthic educator and instructor of cadaver lab at Temple University School of Podiatric Medicine in Philadelphia and owner/operator of Northeast Pedorthic Services in Wilkes-Barre, Pa.
Research over the years
Chromey’s research and literary review have demonstrated that PTTD dates back to discussion in the early 1970s, although the four categories were not determined until 1984 by Mueller.
Johnson and Strom linked the tendon pathology to both clinical and radiograph findings 5 years later; and, in 1992, Holmes and Mann realized that more than half of patients with an adult acquired flatfoot had diabetes, hypertension or obesity, or some combination of those.
In 2004, Chromey
and pedorthic alumni at Temple University School of Podiatric Medicine
Cadaver Lab linked PTTD incidence to patients who developed at least a one-half inch shorter leg over the course of their lifetimes.
follows the school of thought that as long as the foot remains flexible, the patient should be treated with a functional orthotic.
In the first two stages of PTTD, the traditional orthosis controls the foot in stance phase, which indirectly stabilizes the ankle on the tibia.
Once the foot becomes rigid, however, Chromey
believes it is necessary to graduate to an ankle-foot orthosis (AFO).
employs various AFOs to directly control the ankle and the tibia, assisting the foot from stance phase through swing phase.
Whether an orthotic or orthosis is prescribed, the treatment is only as good as the footwear that they wear, Chromey
“We emphasize the proper extra-wide, extra-depth orthopedic footwear with a rocker sole,” he
team linked PTTD incidence to patients who developed at least a ½" shorter leg during the course of their lifetimes.
Practitioners should remember that treating PTTD is as easy as looking for the patients’ symptoms, Chromey
“We need to listen to our patients, look at the abnormal [wear patterns] on the soles of their shoes, and we need to start measuring legs to see just how much shorter they are,” he