Make an appointment:

MediClinic Cape Town


Netcare Blaauwberg Hospital


British Medical Books Health Issues Computerized Tomography

Incidence

  • calcaneal # = 60% of tarsal bone #’s & 2% of all #’s
  • no method of RX that yields consistently good results

Anatomy

  • has a thin cortical shell except at the posterior tuberosity
  • within the shell is cancellous bone

3 Articular facets

  • on the anterior 1/2 of the calcaneus
  • posterior - on the body
  • middle & anterior - on sustentaculum tali
  • these facets articulate with the talus & form the subtalar joint

Tuberosity

  • most hind part of the calcaneus
  • TA inserts here

Anterior process

  • articulates with cuboid

Bohler’s (or tuber) angle

  • seen on the lateral X ray
  • normally 25 - 40° & must be compared with the other side

Crucial angle of Gissane

  • the wedged shaped lateral process of the talus points into
  • measure 135°(± 10°)

Classification

Essex - Lopresti

  • extra-articulars
    • 25% of calcaneal
    • don’t involve subtalar joint
    • tuberosity, sustentaculum tali, anterior process or body
  • Inta-articular
    • 75%
  • undisplaced
  • displaced
    • tongue type
    • joint (central) depression type
    • comminuted

Mechanism of injury

Extra - articular

  • twisting forces mainly
  • # of the tuberosity - usually avulsion type injuries
  • direct blows can cause any type

Intra - articular

  • usually d/t fall from a height
  • bilateral in 5-10%

Associated injuries

  • 10% dorsal or lumbar spine compression
  • 30% other injuries of the lower limb

Clinical

  • deformity, swelling
    • loss of N contour
    • widened & shortened calcaneus
    • may have severe ST injury, compartment sy.
  • bruise onto the arch of the foot
  • pain
  • associated injuries
    • Th-L spine
    • lower limb

X Ray investigations

  • AP, lateral & axial views
  • films of the ankle joint, lower limb. pelvis & spine are mandatory

AP view

  • calcaneo-cuboid joint
  • subluxation of the talonavicular joint

Lateral view shows

  • tuber angle - 20-40° - compare sides
  • congruity of the post. facet & sub-talar joint

Axial view

  • widening
  • the medial wall, lateral wall & medial facet-sustentacular complex

Isherwood

  • 3 oblique views to demonstrate subtalar joint incongruity
  • lateral oblique - ant facet & ant calcaneal process
  • medial oblique axial projection - middle & post. facets
  • lateral oblique axial projection - posterior facet

CT scan

  • intra - articular’s best evaluated
  • coronal sections show
    • size & no. of fragments
    • amount of joint incongruity
    • amount of fragment displacement
  • essential for pre - operative planning

Extra - articular's

#s of the anterior process

2 Types

  • Avulsion
    • More common - bifurcate ligament attaches here
    • Inversion
  • Compression
    • due to forceful abduction of the foot

NB! don't confuse a # with a calcaneus secondarium on X ray

  • conservative
  • ORIF if large displaced articular fragment
  • If symptomatic non-union - excision

Fracture of the tuberosity

2 Types: (older classifications)

  • beak - superior part of the tuberosity
  • avulsion - inferior part
    • avulsion is probably the mechanism in both types
    • occurs in older people
    • usual mechanism a stepping off a small height
    • determined by the amount of displacement

Undisplaced

  • immobization in 5-10° equinus for 6 weeks
  • PWB & serial X rays to confirm reduction

Displaced

  • ORIF to restore TA to length - screw, cerclage wiring
  • NWB in BK POP for 6 to 8 weeks in 5-10° of equinus

Fractures of the sustentaculum tali

  • twisting injuries
  • rare
  • pain & swelling on the medial aspect of the foot - worse on inverting the foot
  • painful non-union - excision

Fracture of the body

  • usually d/t a fall from a height
  • tuber angle can be affected without subtalar joint involvement

2 types of # displacement may warrant more aggressive treatment:

  • significant widening of the heel -> medial - lateral compression- BK POP 6 weeks
  • decrease in the tuber angle - ? shorten the TA with a << in push off strength
  • traction with a transverse Steinman’s pin
  • once reduction is achieved -> incorporate pin in POP for 4 weeks

Summary of management of extra-articular fractures

  • most will need only
    • compression dressing
    • bed rest & leg elevation to decrease swelling
    • physio & exercises of the ankle & sub-talar joint
    • significant widening - manual compression to << late peroneal tendon irritation
    • NWB for 6 to 8 weeks
    • reliable: crutches & encouraged to do an exercise program
    • unreliable: protected in a BK POP NWB

Prognosis

  • good result usually
  • union always occurs
  • with early mobilization joint stiffness is minimal

Intra - articular

  • Intra - articular
    • Rowe, McLaughlin
  • closed reduction & fixation
    • aim is to restore the subtalar joint Bohler’s angle
    • normal heel width

Essex- Lopresti: axial percutaneous pin for tongue type #’s (Gissane spike)

  • ORIF with or without bone grafting

Apply especially to the joint depression type
Essex-Lopresti’s method: lateral approach, fragment elevation & reduction & fixation with a pin through the tuberosity, no bone graft
Palmer’s method: lateral approach with dislocation of the peroneal tendons, BG McReynolds’ method: medial approach with reduction the medial fragments & fixation with a staple - lateral fragments can be reduced through the # line on the medial side

Primary arthrodesis

Treatment

  • after conservative RX - recovery slow & unsatisfactory d/t
    • disruption of the subtalar joint
    • alteration in hindfoot mechanics (rowe 1963, nade & monahan 1972, slatis 1979)
  • ideal RX = anatomic reduction, stable fixation & early joint mobilization
  • pre-requisite for successful surgical management -> knowledge of the # anatomy

X Ray investigations

  • lateral axial, oblique & AP films
  • coronal CT scans

Plain X Rays

  • descriptions of primary & secondary # lines
  • primary # line
    • crosses the posterior facet of the subtalar joint & separates:
      • smaller medial sustentacular fragment - rarely comminuted & remains attached to the talus by the deltoid ligament
    • a large infero-lateral fragment
      • this creates a 2 part fracture
  • secondary # line
    • starts at the crucial angle & divides the infero - lateral fragment into
      • a. lateral joint fragment
      • b. a body fragment
        • this creates a 3 part #

Essex - Lopresti classification

  • divides the 3 part # into 2 groups
  • according to the position of the secondary # line on the lateral X ray
    • a. tongue type
      • # line runs posteriorly along the body
      • exits laterally below the TA
    • b. joint depression #
      • line runs down the lateral side immediately behind the posterior facet of the subtalar joint
      • more common
  • flattening Bohler’s angle occurs in both groups

CT scans

  • reveals more details of the #
  • classified into four main types
    • The inverted Y type, the commonest, represents a primary fracture into the joint and a secondary fracture of the lateral fragment
    • The large fragment type results from the primary fracture passing far laterally, leaving only a small part of the posterior facet on the lateral fragment
    • The longitudinal split type comprises a primary fracture splitting the facet without secondary fracture or depression
    • The fracture may be too comminuted for classification

Eastwood

  • depression of the lateral joint fragment is rare & simple elevation of this fragment can’t fully reduce #
  • reduction of the medial wall is NB
    • broadening of the heel is d/to displacement of the # fragments at the medial wall
    • reduction will therefore narrow the heel & decrease fibula impingement

Pre-op

  • leg elevation, intermittent compression, backslab & ankle & foot movement

Technique

  • an extended lateral approach
    • to avoid sural nerve injury & problems of soft tissue healing
  • reduce articular surfaces
  • correct varus
  • restore calcaneal width, length & height
  • care of soft tissues
  • may need OT & bone graft

Post op.

  • drain
  • B/K cast (bi-valve), elevation
  • NWB 8-12/52

Indications for surgery

  • significant derangement of the sub - talar joint
  • broadening of the heel with displacement & compromise of the peroneal tendons
  • rotation of the body fragment which likely to upset hind foot mechanics
  • a fixable #

Contra - Indications

  • excessive comminution of the sustentacular fragment - main one
  • juvenile DM & ipsilateral sciatic or tibial nerve disruption - relative CI
  • age, fitness, neuro-vascular status

Complications

  • post traumatic OA - major complication
  • wound necrosis & dehiscence
  • infection
  • loss of reduction
  • malunion
  • neurovascular injury
  • nerve entrapment - branches of the post tibial & sural nerve
  • peroneal tendinitis
  • plantar bone spur - due to loss of heel fat pad

Arthrodesis

  • Pennal & Yadav
    • if anatomic reduction of the posterior subtalar joint is not possible by open reduction -> then subtalar fusion is indicated
  • Thompson
    • triple arthrodesis should be done because there is often unrecognised damage to the T-N joint & C-C joint
  • Campbell
    • if after 2 years the patient is incapacitated & having significant pain with activity then triple arthrodesis is the best salvage procedure