Key Insights On Managing Pediatric Equinus With Orthoses
Pediatric equinus can be a challenging condition to diagnose and treat. With this in mind, these expert panelists discuss the differential diagnosis, the positioning of orthoses to control the condition, and the benefits that various modalities can have in managing the condition.
Q: How do you narrow down the differential diagnosis of pediatric equinus?
A: Edwin Harris, DPM, cites several possible causes for equinus deformity including: hemiplegic and diplegic cerebral palsy, muscular dystrophies, peripheral neuropathy, spinal cord pathology, acquired contractures and idiopathic toe walking syndrome. He says one can narrow the differential diagnosis by starting with the chronology of the toe walking itself.
“Children who start toe walking from the time they first walk are less worrisome than children who walk normally for a period of time and then start toe walking,” points out Dr. Harris.
In general, Dr. Harris says toe walking associated with the muscular dystrophies occurs in older children and their gait patterns suggest pelvic weakness. In these cases, Dr. Harris advises clinicians to draw creatine, phosphokinase and aldolase. If one suspects central nervous system pathology at that level, Dr. Harris advises referring the patient for magnetic resonance imaging (MRI) of the brain and spinal cord.
The major causes of equinus vary with age, according to Mary Keen, MD. One must consider if the deformity is present at birth, if it is symmetric or asymmetric, if there is arthrogryposis and if the condition is syndromic or non-syndromic.
If equinus is asymmetric in a preschool child, Dr. Keen suspects hemiplegic cerebral palsy. If a preschool child has symmetric equinus, she considers various causes of an upper motor neuron syndrome or sensory integration dysfunction. Dr. Keen notes many children with autism spectrum disorders seem to have toe walking tendencies. She also considers idiopathic toe walking (which often tends to run in families) and dystrophin deficient myopathy.
Dr. Keen, Dr. Harris and Robert Bielski, MD, note that birth history is critical. Dr. Harris adds that circumstances surrounding the mother’s pregnancy that could be contributing factors include: premature delivery, maternal bleeding, prolonged labor, nuchal cord, fetal bradycardia, postnatal seizures and respiratory difficulties. He says all of these factors point to possible central nervous system insult and inappropriate acquisition of major motor milestones also suggests some degree of nervous system malfunction.
In addition to ascertaining the birth history, Dr. Bielski encourages clinicians to narrow down the differential diagnosis by asking about the developmental history. He notes that he will ask about changes in strength, coordination, endurance and bladder control. Doing so will usually rule out most of the neuromuscular problems, according to Dr. Bielski.
In the review of systems (ROS), Dr. Keen says one should assess for any associated physical or behavioral abnormalities or concerns.
In regard to the physical examination, Dr. Keen advises clinicians to look for long track signs, range of motion loss, atrophy or hypertrophy among other factors. As part of his exam, Dr. Bielski looks for increased tone, checks tibialis anterior strength and checks the back for signs of dimples, hairy patches or scoliosis.
Dr. Harris says the physical examination, with emphasis on ranges of motion, and neurological evaluation will also help narrow the differential diagnosis. As he points out, abnormal deep tendon reflexes, a positive Babinski sign and alteration in tone implicate the central nervous system.
“Idiopathic toe walkers are preferential toe walkers,” adds Dr. Harris. “They will come down on command but revert to an equinus gait when they are distracted.”
Q: How proximal does an orthosis need to be to control equinus?
A: Dr. Keen notes that an orthosis must enclose the calf to control equinus. She recommends an orthotic wearing schedule that varies depending on the severity of tone (if present), contracture risk based on tone and gait habits, and the degree of severity of the toe walking habit.
The length of the orthosis depends on what one is treating and how severe the equinus is, according to Dr. Bielski. He typically will use a full-length (above calf) ankle-foot orthosis (AFO).