Tarsal Coalition
Reading list:
- p1821
Flat feet in older children may be flexible or rigid. Flexible flat feet have little or no arch when standing, caused by calcaneal valgus. Extension of the great toe or standing on tiptoes will cause the arch to reappear (Gage et al., 2009), and the heel will realign into slight varus (Wenger, 1993b). If an arch cannot be elicited and there is limited subtalar ROM, it is a rigid flat foot. A rigid flat foot signals a problem such as a vertical talus or a tarsal coalition and should be examined in more detail by an orthopedic surgeon. When examining children, the use of a treatment algorithm can assist the physical therapist in determining which flat foot should be referred for further medical evaluation and management (Staheli, 2008). A congenital vertical talus, a rare condition in children, is more prevalent in children with CP or myelomeningocele and is defined as a superior dislocation of the talonavicular joint (Rang, 1993b). The head of the talus lies below the navicular bone, producing what is termed a “rocker-bottom foot deformity.” In a rocker-bottom foot deformity, there is no arch and the foot curves downward where the arch would typically be present. This deformity should be evaluated by an orthopedic surgeon and is generally treated by surgery. A tarsal coalition is a congenital fusion of tarsal bones and may involve several different tarsal bones. The two most common tarsal coalitions are calcaneonavicular and talocalcaneal (Nalaboff & Schweitzer, 2008). The fusion can be fibrous, cartilaginous, or osseous. The incidence of osseous tarsal coalitions is approximately 1% (Stormont & Peterson, 1983). When those of fibrous and cartilaginous origin are added, the incidence increases to approximately 12% (Nalaboff & Schweitzer, 2008). These can cause foot pain and are the most common causes of rigid flat feet in children (Cass & Camasta, 2010).
The decision to treat a flexible flat foot is somewhat controversial; however, there is little scientific evidence that intervention for asymptomatic flat feet is warranted (Pfeiffer, Kotz, Ledl, Hauser, & Sluga, 2006; Staheli et al., 1987; Yao & James, 2015). Some studies have indicated that children who are overweight or obese have lower arches than their counterparts who are not overweight, suggesting that there may be changes in their foot structure (Dowling, Steele, & Baur, 2004; Gilmour & Burns, 2001; Mickle, Steele, & Munro, 2006). A systematic review examined the relationship between pes planus and obesity in children (Stolzman, Irby, Callahan, & Skelton, 2015). The authors found that all studies included in the review indicated a higher prevalence of pes planus in children who are overweight or obese, which increased as weight increased and decreased as the children aged. Pain was not addressed in any of these studies. However, the physical therapist should consider a foot structure examination in children who are obese if they present with foot pain. If persistent pain is present or gross motor skills are affected, further examination is necessary to rule out a deformity such as a tarsal coalition or a vertical talus.
Hemimelia refers to an absence or gross shortening of a bone. Fibular hemimelia is considered the most common of the lower limb deficiencies, with an incidence of 1 to 2 per 100,000 live births (Ghanem, 2008). Etiology is unknown, but it is not thought to be an inheritable condition. The clinical presentation can range from a missing toe or tarsal coalition to the absence of the entire fibular bone. Associated impairments can include hypoplasia, knee instability, genu valgum, limb length inequality, tibial deformity, disruption of the ankle morphology, and possible forefoot defects (Paley, 2016).
Types
- Calcaneonavicular (CN) tarsal coalition
- Talocalcaneal (TC) tarsal coalition
Management
When a tarsal coalition becomes symptomatic there are a variety of treatment options including nonoperative and operative procedures2.
Non-operative treatment includes:
- NSAIDs2
- Activity modifications2
- Arch supports2
- University of California Biomechanical Laboratory (UCBL) Orthosis2
- Short leg cast2
Operative treatments:
Non-operative management
- NSAIDs
- UCBL orthosis2