Tarsal Coalition

Introduction[edit | edit source]

Tarsal coalition

Tarsal coalition describes the complete or partial union between two or more bones in the midfoot and hindfoot. Tarsal coalition refers to developmental fusion and not a fusion that is acquired secondary to a condition eg rheumatoid arthritis, trauma or post-surgical. It can present as osseous (synostosis), fibrous (syndesmosis), or cartilaginous (synchondrosis) connections between the tarsal bones.[1][2] The types of tarsal coalitions

  • Talocalcaneal (45%)
  • Calcaneonavicular (45%)
  • Other: Talonavicular, Calcaneocuboid, Naviculocuneiform, Cubonavicular[3]

Pathological Process[edit | edit source]

In young children the coalition between the bones is cartilaginous which allows motion that is normal or, if restricted is functional. During adolescence the coalition begins to ossify and may become a complete or incomplete bony bridge. As ossification proceeds, motion between bones decreases and may become entirely restricted. When hind foot motion is restricted, a twisting injury whose force might otherwise be dissipated through the several hind foot joints may instead concentrate its action, leading to an inversion sprain. Tarsal coalition has been shown to be associated with a high incidence of ankle sprains in adolescent athletes [4],

Clinical Presentation[edit | edit source]

Adolescent present with the insidious onset of hind foot pain with or without recurrent ankle sprains. Some complain of stiffness in the hind foot. The pain is usually described as coming from the lateral side of the hind foot and ankle. Not only adolescents but older athletes as well may develop symptoms from a tarsal coalition. If there has been incomplete ossification of the coalition, hind foot motion may be sufficiently satisfactory to allow normal foot function into adulthood. A twisting injury may then stretch, tear, or otherwise disrupt the coalition, causing the coalition itself to become painful. This pain is often initially diagnosed as an ankle sprain, although it is not alleviated with the usual therapies. All patients with tarsal coalition have the key finding of absent or diminished subtalar motion. The hindfoot cannot to be everted or inverted when holding the ankle in the neutral position[2]

Epidemiology[edit | edit source]

Tarsal coalition occurs in ~5% of the population, and is congenital. There is a occurs more frequently in males (M:F 4:1), and 50% are bilateral (even if symptomatic only on one side). Pes planus is usually a feature[5].

Diagnostic Procedures[edit | edit source]

Radiographs should be obtained, including AP, lateral, and oblique views of the foot . A calcaneonavicular coalition can usually be seen on the oblique view. A talocalcaneal coalition usually involves the middle facet of the subtalar joint which is near the sustentaculum tali. This condition is sometimes difficult to appreciate on standard radiographic views, and Broden views or computed tomography (CT) scanning of the subtalar joint is necessary[6]

An important finding on routine radiographs that should alert the observer to the possibility of a tarsal coalition is a dorsal beak on the neck of the talus. This beak, which represents a talonavicular traction spur, is indicative of increased stress at that joint. The presence of this beak does not indicate that arthritis or adaptive changes have occurred in the hindfoot,[7]

Physiotherapy management[edit | edit source]

An initial course of immobilization in a short-leg walking cast can be tried for 3 to 6 weeks, which allows the irritation and inflammation to resolve and the child to resume athletics . Should this trial be successful, taping the ankle and hindfoot or the use of an ankle brace should be encouraged if the patient wishes to continue with sports activities.[8]

Other interventions can include[3][9]:

  • Nonsteroidal anti-inflammatories
  • Shoe inserts
  • Habit changes


Calcaneonavicular coalitions tend to have worse outcomes with conservative management compared to talocalcaneal coalitions[3]. If a patient lack improvement in symptoms with physiotherapy and conservative management for at least 6 months, surgical intervention may be indicated[9].

Surgical Treatment[edit | edit source]

The type of surgery recommended for a patient depends on the number and location of coalition(s) present.

  • Endoscopic vs Open resection[9]
    • Endoscopic resection may be indicated for calcaneonavicular coalitions and talocalcaneal coalitions of the posterior facet
    • Open resection may be indicated for anterior and middle facet involvement for talocalcaneal coalitions
  • Medial Excision of Subtalar Coalition
  • Lateral  Excision of Calcaneonavicular Coalition
    • Excellent results have been obtained with surgical excision of both calcaneonavicular and subtalar coalitions, even in the presence of a significant talar beak
  • Arthrodesis is the alternative surgical treatment of the hindfoot. This operation eliminates pain but at the expense of function, however which negatively affects athletic performance.
    • Should excision of the coalition not be successful, arthrodesis can be subsequently performed. Subtalar coalitions involve the middle facet and arise just above the sustentaculum tali. They are approached through a medial hindfoot incision. Calcaneonavicular coalitions occur in the anterior part of the sinus tarsi and are approached laterally .[4]

Postoperative Management (Medial Excision of Subtalar Coalition)[edit | edit source]

The patient kept non-weight-bearing, with the splint worn for 10 to 14 days, at the end of which time the skin sutures are removed. The patient continues on crutches, non weight-bearing, for 6 weeks after the surgery .Range of motion exercises are started when the sutures are removed. Return to activity usually occurs at approximately 2 to 3 months.

Postoperative Management  (Lateral Excision of Calcaneonavicular Coalition)[edit | edit source]

The patient is kept non-weight-bearing for 6 weeks. After suture removal at 10 to 14 days, range-of-motion exercises are started. Activity is advanced as tolerated, after resumption of weight-bearing.

Differential Diagnosis[edit | edit source]

References[edit | edit source]

  1. Klammer G, Espinosa N, Iselin LD. Coalitions of the tarsal bones. Foot and ankle clinics. 2018 Sep 1;23(3):435-49.
  2. 2.0 2.1 Marder RA, Lian GJ. Sports injuries of the ankle and foot. Springer Science & Business Media; 2012 Dec 6.
  3. 3.0 3.1 3.2 Soni JF, Valenza W, Matsunaga C. Tarsal coalition. Curr Opin Pediatr. 2020 Feb;32(1):93-99.
  4. 4.0 4.1 Morgan Jr RC, Crawford AH. Surgical management of tarsal coalition in adolescent athletes. Foot & ankle. 1986 Dec;7(3):183-94.
  5. Radiopedia Tarsal Coalition Available: https://radiopaedia.org/articles/tarsal-coalition?lang=gb (accessed 3.7.2022)
  6. Crim JR, Kjeldsberg KM. Radiographic diagnosis of tarsal coalition. American Journal of Roentgenology. 2004 Feb;182(2):323-8.
  7. O'Neill DB, Micheli LJ. Tarsal coalition: A followup of adolescent athletes. The American Journal of Sports Medicine. 1989 Jul;17(4):544-9.
  8. Morgan Jr RC, Crawford AH. Surgical management of tarsal coalition in adolescent athletes. Foot & ankle. 1986 Dec;7(3):183-94.
  9. 9.0 9.1 9.2 Docquier PL, Maldaque P, Bouchard M. Tarsal coalition in paediatric patients. Orthop Traumatol Surg Res. 2019 Feb;105(1S):S123-S131.