calcaneonavicular coalition cover

calcaneonavicular coalition

case presentation

A healthy, 14-year-old male presents with progressive heel pain.  The pain is somewhat progressive and is exacerbated by activity.  On examination, you find somewhat rigid pes planus and radiographs are ordered.  A report returns mentioning that a tarsal coalition is suspected.  What is the most common tarsal coalition? 

A. Talocalcaneal coalition
B. Calcaneonavicular coalition
C. Metatarsal coalition
D. Interphalangeal coalition


Calcaneonavicular coalition (CNC) is an abnormal union bridge between the calcaneus and the navicular or tarsal scaphoid bone, and may be osseous (synostosis), cartilaginous (synchondrosis) or fibrous (synfibrosis or syndesmosis) [1]. It is a congenital or acquired condition of the foot that is usually diagnosed in individuals between the ages of eight to twelve years old and may be seen in some sports medicine clinics as a cause of foot pain [2].

The true incidence of tarsal coalitions is unknown as only about 25% of individuals having tarsal coalitions become symptomatic, require investigations, and pursue treatment. A recent cadaveric study has shown an incidence as high as 13% of the population [3]. Although coalitions can occur between any tarsal bones, calcaneonavicular coalitions are the most frequent ones, accounting for 53% of tarsal coalitions [4].

The classical clinical presentation in adolescents is heel pain that worsens with physical activity, difficulty to walk on uneven surfaces along with history of ankle sprains [2,5].

Image 1: Possible physical examination findings with a rigid pes planus on the right foot in a patient with later confirmed calcaneonavicular coalition.  Adopted from [16].

physical examination

There may be a few relevant findings on physical examination. These may include a flattened medial longitudinal arch, peroneal spastic flat foot, and decreased subtalar motion.  Hindfoot valgus deformity, forefoot abduction, collapse of the medial arch may also be found [2,21].


The diagnosis is based on clinical history, physical examination, and imaging tests, starting with radiographies in 3 incidences: anteroposterior (AP), lateral, and oblique- weighted scans. Computed tomography (CT) and magnetic resonance imaging (MRI) are very useful, because they provide a more detailed description of location, size, degenerative changes in joints or of any concomitant coalition, which helps develop a more effective pre-operative planning [6].

Image 2. Fibrocartilaginous coalition between the calcaneus and the navicular.  In D, sagittal T1 MRI shows elongation of the navicular bone creating an abnormal joint with the cuboid bone. (yellow arrow), cysts in the anterior portion of the calcaneus in contact with the navicular.  Adopted from [17].


The first-line treatment for symptomatic tarsal coalitions is by conservative means. This is usually in the form of activity modification, non-steroidal anti-inflammatory drugs (NSAIDs) for pain relief, orthotics, or support via a walking boot or plaster.  There are variable trials with physical therapy and this usually involves resistance exercises and orthotic or taping support [2].

 High-quality evidence for conservative management of patients presenting with CNC remains scarce [2]. A review of the literature shows mostly youth and adolescent patients, with adult population management poorly represented. There are additional case reports of both surgical and nonsurgical management being successful in adults [7].

Image 3.  Sagittal MRI image of the foot. The joint space is reduced and between the two bones there is an intermediate-to-low signal intensity similar to the fluid or cartilage, suggesting a non osseous calcaneonavicular coalition.  Adopted from [16].

Surgical resection of coalition is indicated when there is no improvement with conservative measures [2]. Corrective osteotomies may be used in cases when calcaneonavicular coalition is associated with pes planus valgus, or arthrodeses when it is associated with joint degeneration.

The standard procedure for CNC resection is the open anterolateral approach (OA) known as Ollier’s [8].  The procedure consists of resecting the coalition, supplementing with muscle or fat interposition to prevent recurrence [9-11].  The long-term results of OA procedures are satisfactory [9]. 

Several authors have proposed arthroscopic resection to reduce the morbidity of the procedure, and to accelerate recovery [4,12-13].  A preliminary study by Bourlez et al. reported a mean short-term AOFAS score of 89.1 in 10 patients with an arthroscopic approach [14]. Although the results of arthroscopic approach seem promising, there has been no comparison of the results of CNC resection by arthroscopic versus Ollier’s approach in the literature [14].

Image 4.  Visualization portal, posterior to the anterolateral process of the calcaneum (dorsal to angle of Gissane). Adopted from [14].

The literature indicates that surgical resection may be preferred in younger patients with calcaneonavicular coalitions with no evidence of arthritic changes or coalitions in other tarsal joints [9]. However, no literature has compared the effectiveness of the different interventions on an adult population nor looked at the complications patients may experience if they choose one intervention over the other. Adults differ from children in that their feet have achieved skeletal maturity and thus management may differ.


In summary, tarsal coalition is a congenital condition, involving abnormal fusion between tarsal bones, often resulting in decreased mobility, pain and deformity leading to a rigid planovalgus foot . Clinical examination and three radiographic views of the foot, anteroposterior, 45 internal oblique and lateral, are often sufficient for the diagnosis of most calcaneonavicular coalitions. Nevertheless, fibrous and many cases of cartilaginous coalitions cannot be identified with standard radiographic examination and further investigations with CT and MRI are needed. In almost all cases, conservative treatment is the initial choice. Surgery with excision of the bar that bridges the two bones gives good results in most patients.


B. Calcaneonavicular coalitions (around 53%) are more common than talocalcaneal coalitions. Together, these two types account for about 90 percent of all coalitions.  The other two options are not common types of tarsal coalitions. 

– More Tarsal Coalition @ Wiki Sports Medicine:


  1. Guignand D, Journeau P, Mainard-Simard L, Popkov D, Haumont T, Lascombes P. Child calcaneonavicular coalitions: MRI diagnostic value in a 19-case series. Orthopaed Traumatol Surg Res. 2011;97:67–72.
  2. Shirley E, Gheorghe R, Neal KM. Results of nonoperative treatment for symptomatic tarsal coalitions. Cureus. 2018;10(7):1–7.
  3. Rühli FJ, Solomon LB, Henneberg M: High prevalence of tarsal coalitions and tarsal joint variants in a recent cadaver sample and its possible significance. Clin Anat. 2003, 16:411-5. 
  4. Knörr J, Accadbled F, Abid A, Darodes P, Torres A, Cahuzac JP, de Gauzy JS: Arthroscopic treatment of calcaneonavicular coalition in children. Orthop Traumatol Surg Res. 2011, 97:565-8.
  5. Mosier KM, Asher M: Tarsal coalitions and peroneal spastic flat foot. A review . J Bone Joint Surg Am. 1984, 66:976-84.
  6. Lawrence DA, Rolen MF, Haims AH, Zayour Z, Moukaddam HA. Tarsal coalitions: radiographic, CT, and MR imaging findings. HSS J. 2014;10(2):153-66.
  7. Kurman K, Romanelli A. Calcaneonavicular coalition: a case study of non-operative management in an adult patient. J Can Chiropr Assoc. 2021 Dec;65(3):350-359.
  8. Docquier P-L, Maldaque P,  Bouchard M. Tarsal coalition in paediatric patients. Orthop Traumatol Surg Res 2019; 105(1S): S123–S131.
  9. Moyes ST, Crawfurd EJ,  Aichroth PM. The interposition of extensor digitorum brevis in the resection of calcaneonavicular bars. J Pediatr Orthop 1994; 14(3): 387–388. 
  10. Masquijo J, Allende V, Torres-Gomez A, et al. Fat graft and bone wax interposition provides better functional outcomes and lower reossification rates than extensor digitorum brevis after calcaneonavicular coalition resection. J Pediatr Orthop 2017; 37(7): e427–e431. 
  11. Mubarak SJ, Patel PN, Upasani VV, et al. Calcaneonavicular coalition: treatment by excision and fat graft. J Pediatr Orthop 2009; 29(5): 418–426.
  12. Lui TH. Arthroscopic resection of the calcaneonavicular coalition or the « too long » anterior process of the calcaneus. Arthroscopy 2006; 22: 903.e1–904.e. 12. Bauer T, Golano P,  Hardy P. Endoscopic resection of a calcaneonavicular coalition. Knee Surg Sports Traumatol Arthrosc 2010; 18: 669–672. 
  13. Molano-Bernardino C, Bernardino P, Garcia MA, et al. Experimental model in cadavera of arthroscopic resection of calcaneonavicular coalition and its first in-vivo application: preliminary communication. J Pediatr Orthop B 2009; 18(6): 347–353.
  14. Bourlez J, Joly-Monrigal P, Alkar F, et al. Does arthroscopic resection of a too-long anterior process improve static disorders of the foot in children and adolescents. Int Orthop 2018; 42(6): 1307–1312.
  15. ​​Duffaydar H, Elmajee M, Dermanis A A, et al. (November 08, 2022) Post-interventional Outcomes in the Management of Adult Calcaneonavicular Coalitions: A Systematic Review. Cureus 14(11): e31253. 
  16. Efstathopoulos, Nicolas, et al. “Calcaneonavicular coalition.” European Journal of Orthopaedic Surgery & Traumatology 16.1 (2006): 70-74.
  17. Juncay, Mercedes, et al. “Calcaneonavicular coalition resection: technical tip.” Journal of the Foot & Ankle 14.3 (2020): 297-300.