- Dr. Michael
Children with Limited foot mobility and pain in the foot? -Might hint to TARSAL COALITIONES!
Tarsal coalition is an abnormal connection that develops between two bones in the back or centre of the foot (the tarsal bones). This abnormal connection, which can be composed of bone, cartilage or fibrous tissue, may lead to limited motion and pain in one or both feet.
Usually at the 8th week of foetal life in the uterus the process of bone separation of the legs [skeletal] is already occurring. In rare cases, if this separation process in the area of joints is incomplete, this consecutively leads to the formation of coalitions, which in many cases occur on both right and left foot. These coalitions are initially fibrous and form an incomplete or complete bony bridge.
Tarsal bones function as a precise clockwork in the foot. These fibrous, cartilaginous or bony bridges affect the normal free mobility of the tarsal bones which causes foot pain due to overuse and shear forces in the tarsal bones.
Coalitions are among the most common diseases of the child’s foot requiring surgery, which is about 1% (compared to idiopathic clubfoot 0.1-0.2%). However, many cases remain unnoticed until the child happen to have an Injury which leads to clinical signs or diagnosed late.
In some cases, acute complaints improve with conservative treatment, while in other instances a surgical procedure must be considered for persistent complaints.
is a common form of a tarsal coalition. Usually, between the navicular and the calcaneal bone[feet bones], there is a ligament ( ligamentum bifurcatum). In a coalition, this ligament is transformed into a fibrous, and at 8 to 12 years of age gradually forms a fibrous, cartilaginous or bony bridge. This causes reduced and restricted tarsal movement with limitation of inward and outward ankle movement, which then often leads to stress pain in ankle joint. Also, peroneal spasms and overuse findings in the Talonavicular joint are seen.
As a diagnosis apart from the restricted inward and outward ankle movement, a simple X-ray usually shows already the underlying problem. An MRI can confirm fibrous pathologies which sometimes can make diagnostic problems as they might not been seen in a normal x-ray. Therapeutically improvement of condition is much favourable with early surgery.
The second more common form of tarsal coalitions is found in the Inner area of the ankle joint, most often involving the Inner, middle facet of the talocalcaneal joint. The expansion of the initially fibrous, later progressed bony bridge formation can include very different parts of the lower ankle. Pain often occurs between the ages of 12 to 16 years in the area of the coalition, but often also at the outer side of the foot due to reduced mobility in specific areas.
Besides the clinical symptoms of reduced mobility and pain, the typical signs in the X-ray can lead to the diagnosis [Talar head ossifications and C-sign]. In these cases, an MRI or CT scan is also recommended to help the surgeon planning the treatment.
The indication of surgical treatment is particularly tricky in the talocalcaneal coalition in childhood and adolescents. A surgery here sometimes does not necessarily guarantee a pain-free situation, but an early treatment usually has a higher success rate after surgical treatment. There are some other vital factors too for a successful treatment outcome as, e.g. muscular contracture status and presented foot deformities.
The postoperative follow up can be lengthy with months of existing complaints. This is due to the fact that the joints have been in certain situations and alignments for many years and the resection of the coalition only creates the basis for the restoration of a certain partial mobility. In a certain percentage a secondary correction of the position of the foot or complete arthrodesis [fusion of joints] might be needed. Here especially in the talocalcaneal coalitions a secondary arthrodesis might in case be a reasonable solution to get a finally pain free situation.