CALCANEAL TUBEROSITY FRACTURES
Achilles Avulsion | ORIF Required | Tension Band Wiring
FRACTURE PATTERNS
Critical Must-Knows
- Calcaneal tuberosity fracture = Achilles tendon avulsion injury - loss of plantarflexion power
- ORIF required if displaced - Prevents equinus contracture and loss of push-off strength
- Tension band wiring preferred - Converts tensile force to compression, allows early motion
- Achilles tendon attached - Tuberosity is insertion site, avulsion causes loss of function
- Sural nerve at risk - Posterior approach, protect nerve during exposure
Examiner's Pearls
- "Achilles tendon avulsion = loss of plantarflexion power, cannot push off
- "ORIF required if displaced - prevents equinus contracture
- "Tension band wiring preferred - allows early motion
- "Sural nerve at risk in posterior approach
Critical Calcaneal Tuberosity Fracture Exam Points
Achilles Avulsion
Calcaneal tuberosity fracture = Achilles tendon avulsion - Tuberosity is insertion site for Achilles tendon. Avulsion causes loss of plantarflexion power and inability to push off. ORIF required if displaced.
ORIF Required
Displacement requires ORIF - Prevents equinus contracture and loss of push-off strength. Tension band wiring preferred - converts tensile force to compression, allows early motion. Screw fixation alternative.
Sural Nerve
Sural nerve at risk in posterior approach - Runs 1-2cm posterior to lateral malleolus. Injury causes lateral foot numbness and painful neuroma. Protect nerve during exposure.
Tension Band
Tension band wiring preferred - Converts tensile force from Achilles to compression at fracture site. Allows early motion and weight bearing. Screw fixation alternative but less biomechanically favorable.
Calcaneal Tuberosity Fractures - Quick Decision Guide
| Pattern | Displacement | Treatment | Outcome |
|---|---|---|---|
| Type I | Beak fracture, superior | ORIF with tension band | 80-90% good results |
| Type II | Avulsion, middle | ORIF with tension band | 80-90% good results |
| Type III | Infrasyndesmotic, inferior | ORIF with tension band | 75-85% good results |
ACHILLESCalcaneal Tuberosity Features
Memory Hook:ACHILLES: Achilles avulsion, Calcaneal tuberosity, Heel pain, Insertion site, Loss of plantarflexion, Lateral nerve risk, Equinus contracture, Surgery required!
ORIFTreatment Decision
Memory Hook:ORIF: ORIF Required if displaced, Insertion site, Fixation with tension band!
SURALComplications
Memory Hook:SURAL: Sural nerve risk, Unable to push off, Risk of equinus, Achilles dysfunction, Loss of strength!
Overview and Epidemiology
Calcaneal tuberosity fractures are rare but important injuries involving the posterior tuberosity of the calcaneus, which serves as the insertion site for the Achilles tendon. These fractures represent avulsion injuries and require ORIF if displaced to prevent loss of plantarflexion power and equinus contracture.
Definition
Calcaneal tuberosity fracture: Fracture of the posterior tuberosity of the calcaneus, which:
- Serves as insertion site for Achilles tendon
- Represents avulsion injury
- Causes loss of plantarflexion power
Achilles tendon insertion:
- Location: Posterior tuberosity of calcaneus
- Function: Plantarflexion and push-off
- Avulsion: Excessive tension causes avulsion with bone fragment
Epidemiology
- Incidence: Less than 2% of calcaneus fractures
- Age: Peak 40-60 years (osteoporosis, low-energy trauma)
- Gender: Female predominance (osteoporosis)
- Mechanism: Sudden plantarflexion, fall, or direct trauma
- Associated injuries: Ankle injuries, other foot trauma
Achilles Avulsion
Calcaneal tuberosity fracture = Achilles tendon avulsion - Tuberosity is insertion site for Achilles tendon. Avulsion causes loss of plantarflexion power and inability to push off. ORIF required if displaced to prevent equinus contracture.
Anatomy and Pathophysiology
Calcaneal Tuberosity Anatomy
Posterior tuberosity of calcaneus:
- Location: Posterior aspect of calcaneus
- Function: Insertion site for Achilles tendon
- Size: Large, prominent posterior projection
- Blood supply: Branches from posterior tibial artery
Achilles tendon insertion:
- Location: Posterior tuberosity of calcaneus
- Function: Plantarflexion and push-off
- Width: 1.5-2cm at insertion
- Avulsion: Excessive tension causes avulsion with bone fragment
Sural nerve:
- Location: 1-2cm posterior to lateral malleolus
- Function: Sensory to lateral foot
- Risk: At risk in posterior approach
Pathophysiology
Injury mechanism:
-
Sudden plantarflexion: Eccentric contraction of gastrocnemius-soleus
-
Excessive tension: Achilles tendon experiences excessive tension
-
Avulsion: Tendon avulses from tuberosity with bone fragment
-
Low-energy: Often in osteoporotic patients
-
Low-energy: Often in osteoporotic patients
-
Associated: Ankle sprain variants
Why displacement matters:
- Loss of function: Displacement causes loss of plantarflexion power
- Equinus contracture: Proximal migration causes equinus
- Push-off weakness: Inability to push off affects gait
Why ORIF required:
- Restore function: Anatomic reduction restores plantarflexion
- Prevent contracture: Prevents equinus contracture
- Early motion: Stable fixation allows early motion
Classification Systems
Pattern-Based Classification
Type I (Beak fracture, superior):
- Superior aspect of tuberosity
- Treatment: ORIF with tension band
- Outcome: 80-90% good results
Type II (Avulsion, middle):
- Middle aspect of tuberosity
- Treatment: ORIF with tension band
- Outcome: 80-90% good results
Type III (Infrasyndesmotic, inferior):
- Inferior aspect of tuberosity
- Treatment: ORIF with tension band
- Outcome: 75-85% good results
Pattern guides treatment approach.
Clinical Assessment
History
Symptoms:
- Posterior heel pain: Pain in posterior heel
- Loss of plantarflexion: Unable to push off
- Swelling: Localised to posterior heel
- Difficulty walking: Pain with weight bearing
Mechanism:
- Sudden plantarflexion
- Fall
- Direct trauma to heel
Physical Examination
Inspection:
- Swelling in posterior heel
- Ecchymosis (may be delayed)
- Deformity (proximal migration of fragment)
Palpation:
- Tenderness over calcaneal tuberosity
- Gap at fracture site (if displaced)
- Achilles tendon continuity (may be disrupted)
Range of Motion:
- Loss of active plantarflexion
- Passive plantarflexion may be limited
- Equinus deformity (if displaced)
Special tests:
- Active plantarflexion: Unable to perform (loss of power)
- Thompson test: May be positive (Achilles dysfunction)
- Straight leg raise: May be limited (pain)
Clinical Examination Key Point
Loss of active plantarflexion is key finding - Patient unable to push off or perform single-leg heel raise. This indicates Achilles dysfunction and requires ORIF if displaced.
Investigations
Standard X-ray Protocol
Lateral view (best view):
- Shows calcaneal tuberosity
- Assess displacement
- Proximal migration of fragment
Axial view (Harris view):
- Shows tuberosity from below
- Assess displacement
AP view:
- May show fracture
- Less reliable than lateral
Key point: Displacement greater than 2mm requires ORIF.
Management Algorithm


Management Pathway
Calcaneal Tuberosity Fracture Management
Loss of active plantarflexion is key finding. X-rays show calcaneal tuberosity fracture. Assess displacement - greater than 2mm requires ORIF.
If non-displaced (less than 2mm) and intact extensor mechanism, conservative treatment with cast and non-weight bearing for 6-8 weeks. Success rate 85-90% (rare).
If displaced (greater than 2mm) or loss of plantarflexion, ORIF required. Tension band wiring preferred - converts tensile force to compression, allows early motion. Success rate 80-90%.
Tension band wiring preferred - K-wires or screws with figure-8 wire. Converts tensile force from Achilles to compression at fracture site. Allows early motion and weight bearing. Success rate 80-90%.
Surgical Technique

Tension Band Wiring Technique (Preferred)
Indications:
- Most calcaneal tuberosity fractures
- Displaced fractures
- Allows early motion
Approach:
- Posterior midline or posterolateral approach
- Expose tuberosity
- Protect sural nerve
Technique:
- Exposure: Posterior approach, expose tuberosity, protect sural nerve
- Reduction: Anatomic reduction of fragment to calcaneus
- K-wires: Two parallel K-wires (2.0-2.5mm) from tuberosity into calcaneus
- Tension band: Figure-8 wire (1.2-1.25mm) around K-wires and through Achilles
- Tensioning: Tension wire to convert tensile force to compression
- Verification: Confirm reduction and hardware position fluoroscopically
Advantages:
- Converts tensile force to compression
- Allows early motion
- Biomechanically favorable
- High union rate
Tension band wiring is preferred technique.
Complications
| Complication | Incidence | Risk Factors | Prevention/Management |
|---|---|---|---|
| Sural nerve injury | 5-10% | Posterior approach | Protect nerve, identify early |
| Equinus contracture | 10-15% | Delayed treatment, inadequate fixation | Early ORIF, adequate fixation |
| Loss of plantarflexion | 10-15% | Inadequate reduction, delayed treatment | Anatomic reduction, early treatment |
| Nonunion | 5-10% | Inadequate fixation, displacement | Rigid fixation, bone graft if needed |
| Hardware prominence | 20-30% | Tension band wires | Bury wires, remove if symptomatic |
Sural Nerve Injury
5-10% incidence:
- Cause: Posterior approach, nerve at risk
- Prevention: Identify and protect sural nerve (1-2cm posterior to lateral malleolus)
- Management: Neuroma excision if symptomatic
Equinus Contracture
10-15% incidence (if untreated):
- Cause: Proximal migration of fragment, delayed treatment
- Prevention: Early ORIF, adequate fixation
- Management: Stretching, serial casting, or surgical release
Postoperative Care
Immediate Postoperative
- Immobilisation: Short leg cast or boot
- Weight bearing: Non-weight bearing initially (2-4 weeks)
- ROM: Ankle ROM exercises early (if stable fixation)
- PT: Plantarflexion strengthening
Rehabilitation Protocol
Weeks 0-2:
- Short leg cast, non-weight bearing
- Elevation to reduce swelling
- Ankle ROM exercises (if stable)
Weeks 2-4:
- Transition to walking boot
- Progressive weight bearing (if stable)
- Plantarflexion strengthening
Weeks 4-8:
- Full weight bearing
- Progressive activity
- Return to sport (3-4 months)
Outcomes and Prognosis
Overall Outcomes
ORIF (tension band wiring):
- Success rate: 80-90% (union, pain relief)
- Functional outcomes: 75-85% return to pre-injury level
- Plantarflexion: 80-90% restore normal strength
ORIF (screw fixation):
- Success rate: 75-85% (union, pain relief)
- Functional outcomes: 70-80% return to pre-injury level
- Plantarflexion: 75-85% restore normal strength
Conservative (non-displaced, rare):
- Success rate: 85-90% (union, pain relief)
- Functional outcomes: 80-85% return to pre-injury level
- Plantarflexion: 85-90% restore normal strength
Long-Term Prognosis
Plantarflexion recovery:
- With proper treatment: 80-90% restore normal strength
- Without treatment: 20-30% develop permanent weakness
- Risk factors: Displacement, delayed treatment, inadequate fixation
Evidence Base
Calcaneal Tuberosity Fractures
- Achilles tendon avulsion mechanism
- ORIF required if displaced (80-90% good results)
- Tension band wiring preferred
- Prevents equinus contracture
Tension Band Wiring
- Tension band wiring: 80-90% good results
- Converts tensile to compression
- Allows early motion
- Biomechanically superior
Sural Nerve Injury
- Sural nerve injury: 5-10%
- Nerve at 1-2cm posterior to lateral malleolus
- Causes lateral foot numbness
- Protect during approach
Equinus Contracture
- Equinus contracture: 10-15% if untreated
- Proximal migration causes contracture
- Early ORIF prevents contracture
- Adequate fixation essential
Treatment Outcomes
- ORIF: 80-90% good results
- Tension band wiring preferred
- Restores plantarflexion in 80-90%
- Early treatment improves outcomes
Exam Viva Scenarios
Practice these scenarios to excel in your viva examination
Scenario 1: Displaced Tuberosity Fracture with Loss of Plantarflexion
"A 55-year-old woman presents with posterior heel pain and inability to push off after fall. Clinical examination shows loss of active plantarflexion and palpable gap at calcaneal tuberosity. X-rays show displaced calcaneal tuberosity fracture with 5mm proximal migration."
Scenario 2: Tension Band Wiring Technique
"A 50-year-old patient has a displaced calcaneal tuberosity fracture requiring ORIF. The examiner asks you to describe the tension band wiring technique in detail."
MCQ Practice Points
Achilles Avulsion
Q: What is the relationship between calcaneal tuberosity fractures and Achilles tendon function? A: Calcaneal tuberosity is insertion site for Achilles tendon - Avulsion causes loss of plantarflexion power and inability to push off. ORIF required if displaced to restore function and prevent equinus contracture.
ORIF Indications
Q: When is ORIF required for calcaneal tuberosity fractures? A: Displacement greater than 2mm or loss of active plantarflexion - Prevents equinus contracture and loss of push-off strength. Tension band wiring preferred - converts tensile force to compression, allows early motion.
Tension Band Wiring
Q: Why is tension band wiring preferred for calcaneal tuberosity fractures? A: Converts tensile force from Achilles to compression at fracture site - Biomechanically superior to screw fixation alone. Allows early motion and weight bearing. High union rate (80-90% good results).
Sural Nerve
Q: What structure is at risk in the posterior approach for calcaneal tuberosity fractures? A: Sural nerve - Runs 1-2cm posterior to lateral malleolus. Injury causes lateral foot numbness and painful neuroma. Protect nerve during exposure (5-10% injury rate).
Equinus Contracture
Q: What is the main complication of untreated calcaneal tuberosity fractures? A: Equinus contracture - Proximal migration of fragment causes contracture in 10-15% if untreated. Early ORIF prevents contracture. Adequate fixation essential to maintain reduction.
Australian Context
Clinical Practice
- Calcaneal tuberosity fractures rare but important
- ORIF standard for displaced fractures
- Tension band wiring preferred
- Sural nerve protection critical
Healthcare System
- ORIF covered under public system
- Public hospitals handle most cases
- Private insurance covers procedures
- Osteoporosis common in elderly
Orthopaedic Exam Relevance
Calcaneal tuberosity fractures are a common viva topic. Know that Achilles tendon avulsion mechanism, ORIF required if displaced (prevents equinus contracture), tension band wiring preferred (converts tensile to compression), sural nerve at risk in posterior approach (5-10% injury rate), and loss of plantarflexion is key finding. Be prepared to discuss the tension band wiring technique in detail.
CALCANEAL TUBEROSITY FRACTURES
High-Yield Exam Summary
Key Concepts
- •Calcaneal tuberosity = Achilles tendon insertion site
- •Achilles avulsion = loss of plantarflexion power
- •ORIF required if displaced (greater than 2mm)
- •Tension band wiring preferred (converts tensile to compression)
Classification
- •Type I: Simple extra-articular avulsion (sleeve)
- •Type II: Beak fracture (intra-articular, skin risk)
- •Type III: Body involvement (intra-articular)
- •Key Factor: Skin condition determines urgency
Treatment
- •Non-displaced (rare): Conservative (cast, NWB 6-8 weeks)
- •Displaced (most): ORIF with tension band wiring (80-90% good results)
- •Large fragment: Screw fixation alternative (75-85% good results)
- •Loss of plantarflexion: Absolute indication for ORIF
Surgical Technique
- •Posterior approach: Midline or posterolateral, protect sural nerve
- •Tension band: K-wires (2.0-2.5mm) + figure-8 wire (1.2-1.25mm)
- •Wire anterior to K-wire axis (on tension side)
- •Converts tensile force to compression
- •Verify reduction fluoroscopically
Complications
- •Sural nerve injury: 5-10% (prevent by protecting nerve)
- •Equinus contracture: 10-15% if untreated (prevent with early ORIF)
- •Loss of plantarflexion: 10-15% (prevent with anatomic reduction)
- •Nonunion: 5-10% (prevent with rigid fixation)
- •Hardware prominence: 20-30% (remove if symptomatic)