This document discusses the anatomy, classification, and management of fractures of the talus bone. It describes the different types of talar fractures including neck, body, lateral and posterior process, and head fractures. It outlines the mechanisms of injury, investigations, treatment options including casting, open reduction internal fixation, and excision depending on the fracture type and degree of displacement. Complications of the different fracture types such as avascular necrosis, osteoarthritis, and malunion are also summarized.

1. The Talus
ELHT Teaching Programme
Hiren Divecha (ST4)
14/11/2011

2. Intro
Anatomy
Fractures & Management
1. Neck (50%)
2. Body (23%)
3. Lateral & Posterior processes
4. Head (5%)
5. (OCD)

3. Anatomy
Latin for “ankle”
Also called astragalus
2nd largest tarsal bone
60% covered by articular cartilage
Retrograde blood supply
No muscular attachments
3 parts
Articulations:
1. Tibio-talar
2. Subtalar
3. Talo-navicular

4. Blood Supply

5. Blood Supply

6. Talar Neck Fractures
(Aviator’s astragalus)
Mechanism
Forced dorsiflexion
Axial load
Supination
RTA, fall from height
15-20% open
Assoc. malleloar # (25%)
Investigations
AP, lateral, Canale view
CT
Hawkin-Canale Classification

7. Type 1
Undisplaced (<1 mm)
50% missed on X-ray
Rx
NWB BK cast 6/52
WB in cast further 2-4
weeks

8. Type 2
Displaced
Subtalar disloc
Rx
Immediate closed
reduction
ORIF

9. Type 3
Displaced
Subtalar disloc
Tibiotalar disloc
Body extruded
Skin/ NV compression
>50% open
38% deep infection rate
Rx
Immediate ORIF
Astragalectomy ?

10. Type 4
Displaced
Subtalar disloc
Tibiotalar disloc
Talonavicular disloc
Risk of talar head AVN
Rx
Immediate ORIF
TNJ pinning
Astragalectomy ?

11. ORIF - Approaches
1. Anteromedial
Medial to TA from navicular tub. (mall. osteotomy)
Risk of damage deltoid vessels
Difficult to assess rotation/ length
2. Anterolateral
Lateral to EDL/PT
Least vascular risk
3. Posterolateral
Between FHL/ PL

12. ORIF - Fixation
Lag screws, titanium,
cannulated, graft
AP
Medial + lateral
Countersunk/ headless
PA
Stronger construct
(Swanson JBJS-A 1992)
Risk of subtalar/ lateral
penetration (talar neck
axis!)

13. Risks
Type AVN OA Malunion
I 0-13% 0-30% 0-10%
II 20-50% 40-90% 0-25%
III 69-100% 70-100% 18-27%
IV 90-100% 70-100% >27%

14. Hawkins sign
Subchondral disuse
osteopenia in dome of talus
Revascularization and
atrophic change in the body
of the talus at 6-8 weeks
Good prognostic sign
If absent at 12 weeks – 75% AVN

15. Talar body fracture
Intra-articular (ankle/ subtalar)
# line posterior to lateral
process (ie:post. facet)
Much poorer prognosis than
talar neck fractures
ORIF
Medial approach with
malleolar osteotomy
High risk of AVN, malunion &
OA
Astragalectomy, arthrodesis

16. Lateral Process #
ATFL attachment
Snowboarder’s #
Mechanism
Axial load, dorsiflexion, external rotation
Often misdiagnosed as lateral sprain
Rx
Undisplaced – NWB BK cast 6-8 weeks
Displaced (>2mm) – ORIF (>1cm), excision

17. Lateral Process #

18. Lateral Process #

19. Posterior Process #
Lateral – Shepherd’s #
(PTFL)
Medial – Cedell’s #
Can be mis-diagnosed as
ankle sprain
Pain on passive toe
movement (FHL)
Rx
Undisplaced – NWB BK cast
6-8 weeks
Displaced – ORIF, excise

20. Talar Head #
< 10% of talar #s
Mechanism
axial loading with the ankle in plantar flexion, against the
distal tibia with ankle in dorsiflexion
Often TNJ dislocation
Rx
Nondisplaced - NWB BK cast 8-12 weeks
Displaced – excision (<50%), ORIF (>50%), TNJ arthrodesis
Complications
OA, AVN(10%)

21. References
Fortin PT & Balazsy JE. Talus Fractures: Evaluation and
Treatment. J Am Acad Orthop Surg 2001;9:114-127
Hawkins LG. Fractures of the neck of the talus. J Bone Joint
Surg Am 1970;52: 991-1002
Canale ST, Kelly FB. Fractures of the neck of the talus:
Long-term evaluation of seventy-one cases. J Bone Joint
Surg Am 1978;60:143-156
Swanson TV et al. Fractures of the talar neck: A mechanical
study of fixation. J Bone Joint Surg Am 1992;74:544-551