- See:
-
Talocalcaneal Coalition:
-
Calcaneonavicular Coalition:
- Discussion:
- coalition between tarsal bones is frequent cause of painful flatfoot (pes planus) in the older child or adolescent;
- tarsal coalition may be osseous, cartilaginous, or fibrous.
-
calcaneonavicular coalition bar is most common, followed by
middle facet of
talocalcaneal coalition joint;
- single coalition is most common, > one are occassionally found
- there is a tendency to progressive ossification of bar w/ increasing age, and this often corresponds with the onset of symptoms;
- ossification occurs at 8 - 12 yrs for calcaneonavicular bars and between 12 - 15 years for talocalcaneal coalitions.
-
ankle sprain are common;
- autosomal dominance w/ variable penetrance is mechanism of inheritance;
- majority of tarsal coalitions are asymptomatic, & evidence indicates that they remain so in adulthood;
- symptomatic lesions often are treated initially by immobilization for three to six weeks, followed by an orthosis;
- Exam:
- painful
flat foot, limitied subtalar movement, and tenderness in subtalar area;
- valgus heel and everted forefoot w/ limited sub talar motion
- w/ progressive restriction of motion in the
sub-talar joint, compensatory movement occurs at ankle, leading to ligamentous laxity;
- subtalar motion is decr, esp for talocalcaneal bar, & rigid flatfoot w/ contracture of peroneal tendons (peroneal spastic flatfoot) exists;
- pain in subtalar or midtarsal area often develops in early adolescence & is typically relieved by rest;
- restricted subtalar motion leads to spasm of peroneal muscles, hence the term "peroneal spastic flatfoot."
- patients are often unable to stand on lateral aspect of foot;
- Radiographic Studies:
-
radiographic features of talocalcaneal coalition;
- radiographic features of calcaneonavicular coalition:
- lateral view:
- often has signs suggestive of coalition:
- blunting of subtalar process, elongation of anteior calcaneal process, narrowing of posterior subtalar joint, & talar beaking;
- Non Operative Treatment:
- asymptomatic coalition does not require surgical treatment;
- orthotic objectives:
- reduce subtalar motion or stresses;
- reduce medial-lateral hindfoot forces;
- UCBL
- total contact orthosis supporting
subtalar joint;
- high top for medial lateral stability;
- Indications for Surgery:
-
talocalcaneal coalition:
-
calcaneonavicular coalition:
- for symptomatic coalition before degenerative changes have occured usually in pts under age of 14 years), resection is usual treatment;
- this procedure is not appropriate if cartilagenous bar is completely ossified and degenerative changes have occurred or
if coalition between the talus and
calcaneus is also present;
- in pts over age of 14, who have degenerative changes, a below knee, wt bearing cast, a plastizoate insert for the shoe, or an AFO may relieve the pain;
- failure to respond to these conservative measures & presence of degenerative changes indicate the need for
triple arthrodesis;
Subtalar fusion for isolated subtalar disorders. Preliminary report.
Resection as a method of treatment of tarsal coalitions [letter.
Mann RA.
Journal of Bone & Joint Surgery - American Volume.
70(5):791, 1988 Jun.
The inheritance of tarsal coalition and its relationship to spastic flat foot.
Leonard MA: J Bone Joint Surg (Br) 1974;56B:520.
Tarsal coalitions:
Long term results of surgical treatment.
Swiontkowski MF, Scranton PE, Hansen S:
J Pediatr Orthop 1983;3:287-292.
Surgical management of tarsal coalition in adolescent athletes.
Morgan RC, Crawford AH:
Foot Ankle 1986-87;7:183-193.
Sarrafian SK:
