What is tarsal coalition?
Tarsal coalition is a condition characterised by congenital fusion of two or more rear foot bones known as the tarsals.

Occasionally two or more tarsal bones may fuse together and become interconnected. This is usually a congenital abnormality that is present from birth and is relatively uncommon. This condition is known as tarsal coalition.

Tarsal coalition in itself is not a painful condition. However, due to altered biomechanics and reduced shock absorption associated with the fused bones, increased stress may be placed on this or other areas of the foot and lower limb when carrying weight on the foot. This may result in pain and injury and is particularly common in adolescents who suddenly increase their activity levels or begin sports participation. Tarsal coalition may also increase the likelihood of adults developing painful bone spurs at sites away from the fused bones.

Cause of tarsal coalition
Tarsal coalition is a congenital abnormality that is present in a small percentage of the population from birth. There is often a family history of the condition and it may occur in both feet.

Signs and symptoms of tarsal coalition
Patients with this condition are usually completely asymptomatic. However, due to abnormal biomechanics and reduced shock absorption associated with this condition, the affected region or other structures within the foot and lower limb may be subject to additional stress and potential injury as a result of the bone fusion.

Symptoms associated with tarsal coalition are more likely to develop following a sudden increase in strain on the foot or sporting activity, and typically present as mid-foot or rear-foot pain or stiffness, or occasionally as a sprained ankle that does not settle. Strenuous exercise involving activity over rough ground, jumping or twisting and turning may be particularly aggravating. The pain may be associated with a limp. Rest from strenuous activity usually relieves symptoms. On examination there is usually stiffness present in the rear or mid-foot and abnormal biomechanics are usually evident.

Adults with this condition sometimes experience pain and bone spurs in other regions of the foot which may be associated with this condition. In the young athlete, a tarsal coalition may first present as an acute ankle sprain or as a history of repeated ankle sprains.

Diagnosis of tarsal coalition
A thorough subjective and objective examination from a physiotherapist or doctor is important to assist with diagnosis of tarsal coalition. An X-ray is usually required to confirm diagnosis. Investigations such as an MRI, bone scan or CT scan may be required in some cases to confirm diagnosis and rule out other injuries (particularly fractures).

Treatment for tarsal coalition
Most patients with symptoms associated with tarsal coalition make a good recovery with appropriate physiotherapy. One of the key components of treatment is that the patient rests sufficiently from ANY activity that increases their pain until they are symptom free (crutches, orthotics, protective taping or bracing may be required).

Rest from aggravating activities ensures the body can begin the healing process in the absence of further tissue damage.

Treatment in the first 48-72 hours of injury is vital to reduce bleeding, swelling and inflammation. This should involve following the R.I.C.E regime, which comprises rest from aggravating activities (crutches are often required), regular icing, the use of a compression bandage and elevation of the affected limb. Anti-inflammatory medication may also be useful in this initial phase of injury and can hasten the healing process by reducing the pain and swelling associated with inflammation.

It is also important for patients with tarsal coalition to perform range of movement, strengthening and balance exercises early in the rehabilitation process to prevent stiffness and weakness from developing and to ensure the foot and ankle are functioning correctly. These exercises should generally be implemented as soon as pain allows and should be guided by the treating physiotherapist.

In some cases orthotics may be required as part of treatment and symptom prevention.

Prognosis of tarsal coalition
Many patients with this condition experience little or no symptoms. Most patients who develop pain due to abnormal biomechanics associated with their bone fusion settle well with appropriate physiotherapy. Patients with more severe injuries or who require other intervention (such as surgery) will require a longer period of rehabilitation to gain optimum function.

Physiotherapy for tarsal coalition
Physiotherapy for patients with symptomatic tarsal coalition can hasten the healing process, ensure an optimal outcome and reduce the likelihood of symptom recurrence. Treatment may comprise:

  • Soft tissue massage
  • Electrotherapy
  • Anti-inflammatory advice
  • Joint mobilisation
  • The use of crutches
  • Orthotics
  • Footwear advice
  • Protective taping
  • The use of a brace
  • Ice or heat treatment
  • Exercises to improve flexibility, strength and balance
  • Activity modification advice
  • A gradual return to activity

Other intervention for tarsal coalition
Despite appropriate physiotherapy management, a small percentage of patients with this condition do not improve adequately and require other intervention. When this occurs the treating physiotherapist or doctor can advise on the best course of management. This may involve further investigation such as an X-ray, CT scan, bone scan or MRI, pharmaceutical intervention, corticosteroid injection or a review by a specialist who can advise on any procedures that may be appropriate to improve the condition.

Surgery should be considered in those cases where the patient continues to suffers ongoing pain or ankle sprains and where conservative management has failed. Surgery may involve excision of the bone fusion between the two bones. Following this, the patient is rested in a cast for a few weeks, followed by activity restrictions for a number of weeks and a gradual, progressive rehabilitation program.

A review with a podiatrist for the prescription of orthotics may sometimes be indicated.