When Pediatric Flatfoot Requires Surgical Correction
Pediatric symptomatic flatfoot problems are very common in foot and ankle practices. Although calf stretches and orthotics are effective for most patients, there is a subset of patients who require surgical correction.
With time, the type and thoughts for surgery have changed and become more advanced. This has led to better short- and long-term results. Accordingly, let us take a closer look at the underlying causes of pediatric flatfoot ailments and appropriate procedure selection for improved outcomes. The first and by far the most important point to consider with any flatfoot correction is the underlying cause of the flatfoot and what is referred to as the plane of abnormal dominance.
It is important to remember that the foot is a tripod. In order for the foot to work properly, all three parts of the tripod (in this case the heel, first metatarsal and fifth metatarsal) need to be on the ground at the same time. Furthermore, the posterior tendons, especially the gastrocnemius tendon and Achilles proper, need to be supple enough not to put heavy strain on the tripod, which can cause collapsing of the arch.
What To Look For In The Clinical Exam
When it comes to the clinical exam, one needs to consider the foot in both standing and sitting position. When the patient is standing, pay attention to the level of arch collapse and splaying or widening or the foot. Check the hindfoot position with the amount of heel valgus and lateral tarsal deviation. Realign the arch with the patient standing and check the amount of correction. Check the suppleness of the hindfoot and forefoot. Finally, check forefoot alignment while the hindfoot is in a corrected position.
During the seated exam, check the tightness of the Achilles and gastrocnemius muscle group. Perform this with the patient’s knee straight and bent. If motion improves to neutral or better dorsiflexion with the knee bent, a gastrocnemius equinus is present. If there is little change in the ankle range of motion with the knee bent, an Achilles equinus is present.
Again note the range of motion of the joints and check any concern for a possible coalition. In young children, the joints are so supple that it is often difficult to determine the presence of a coalition due to the range of motion of the surrounding joints. However, as coalitions are often one-sided, it is important to consider a unilateral flatfoot a coalition until proven otherwise.
The most important consideration of the exam is to check the hindfoot to forefoot alignment. First, consider what type of hindfoot correction is necessary to realign the heel. Is the deformity mainly lateral deviation of the tarsals or a calcaneal valgus?
After considering the hindfoot correction, one must address forefoot realignment needs. The main reason I see failures in pediatric flatfoot correction is correction of hindfoot deformity without attention to the forefoot. For example, if you are going to correct the hindfoot with a subtalar implant that will correct valgus heel position, you will increase the forefoot varus deformity.
One must also correct the forefoot varus deformity in order to bring the first ray to the ground. If this goes uncorrected, the forefoot will have to reach the ground by collapsing, which will result in jamming of the implant in the subtalar joint. Always consider that a slide procedure of the hindfoot such as an Evans opening wedge or a calcaneal slide will decrease the forefoot varus in comparison to a rotation procedure like one would perform with a subtalar implant. After selecting the hindfoot and forefoot procedures, and considering the equinus concerns, one can proceed with procedure selection.
Pertinent Insights On Procedure Selection
Here are a few guidelines that I like to follow that may be helpful.