Tarsal Coalition in Children
Key Points
- Abnormal bridge between tarsal bones (1% population)
- Usually presents in late childhood/early adolescence
- Can be fibrous (syndesmosis), cartilaginous (synchondrosis), or bony (synostosis)
- Most common: calcaneonavicular (45%) and talocalcaneal (45%)
- Often bilateral (50-60% cases)
Definition & Classification
Tarsal coalition represents an abnormal connection between two or more tarsal bones, resulting from failure of mesenchymal separation during embryological development. This connection can be fibrous, cartilaginous, or osseous.
Types of Coalitions
- Calcaneonavicular Coalition
- Most easily diagnosed
- Typically symptomatic age 8-12 years
- Presents with lateral foot pain
- Talocalcaneal Coalition
- More complex diagnosis
- Usually symptomatic age 12-16 years
- Middle facet most common
- Rare Coalitions
- Calcaneocuboid
- Talonavicular
- Cubonavicular
Genetic Associations
- Autosomal dominant inheritance pattern
- Associated conditions:
- Apert Syndrome
- Carpenter Syndrome
- Nievergelt-Pearlman Syndrome
- Multiple Synostosis Syndrome
Clinical Features
Symptoms
- Primary Symptoms:
- Gradual onset of rigid flatfoot
- Activity-related pain
- Frequent ankle sprains
- Limited subtalar motion
- Pain Characteristics:
- Typically worse with impact activities
- Located in sinus tarsi region
- May have associated muscle spasms
- Aggravated by uneven ground
- Adaptive Changes:
- Shortened gastrocnemius-soleus complex
- Peroneal spasm
- Altered gait pattern
Physical Examination
- Standing Assessment:
- Rigid flatfoot deformity
- Limited hindfoot motion
- Asymmetric wear pattern
- Special Tests:
- 'Reverse Coleman' block test
- Single limb heel rise
- Forced inversion/eversion
Diagnosis & Assessment
Radiographic Evaluation
- Standard Views:
- Weight-bearing AP, lateral, oblique
- Harris-Beath projection
- 45° medial oblique (calcaneonavicular)
- Key Radiographic Signs:
- Calcaneonavicular Coalition:
- 'Anteater nose' sign
- Elongated anterior process
- Talocalcaneal Coalition:
- 'C' sign on lateral view
- Talar beaking
- Dysmorphic sustentaculum tali
- Calcaneonavicular Coalition:
Advanced Imaging
- CT Scan:
- Gold standard for osseous coalition
- Best for surgical planning
- Shows extent and type of coalition
- MRI:
- Better for fibrous/cartilaginous coalitions
- Shows associated soft tissue changes
- Evaluates bone marrow edema
Management Approach
Conservative Treatment
- Initial Management:
- Activity modification
- NSAIDs for pain control
- Short-term immobilization
- Orthotic devices
- Physical Therapy:
- Ankle ROM exercises
- Peroneal stretching
- Gastrocnemius-soleus stretching
- Proprioception training
Surgical Management
- Indications:
- Failed conservative treatment (6-12 months)
- Persistent pain
- Functional limitation
- Progressive deformity
- Calcaneonavicular Coalition:
- Resection with interposition
- Fat/muscle/extensor digitorum brevis
- Success rate 75-85%
- Talocalcaneal Coalition:
- Resection if < 50% involvement
- Triple arthrodesis for:
- Large coalitions
- Degenerative changes
- Failed resection
Postoperative Care
- Week 0-6:
- Non-weight bearing in cast
- DVT prophylaxis as needed
- Week 6-12:
- Progressive weight bearing
- ROM exercises
- Physical therapy initiation
- 3-6 months:
- Return to activities
- Sport-specific training
