Ankle and foot anatomy and arthrodesis

1. Ankle & Foot
Arthrodesis
Dr. Jayesh A Bhanushali
D.ortho
Registrar, RGMC & CSMH
Kalwa, Thane.

2. Overview
• Anatomy
• History
• Indications
• Surgical Options
• Complications
• Outcomes

3. Anatomy
• Tibiotalar joint is a hinge joint
– consists of talar dome, tibial plafond and two malleoli.
• Isolated movement occurs in the sagittal plane
– 15-30o
dorsiflexion to 30-50o
plantar flexion
• Small amounts of movement in coronal and
axial planes
– IR/ER in axial plane
– Inversion/Eversion in coronal plane

5. What is Arthrodesis?
• It is a procedure designed to produce bony ankylosis in a joint in
which motion is undesirable.
• Satisfactory solution for infections, tumour, trauma, paralytic
conditions, OA and RA.
• It is a standard reconstructive technique for treatment of
disabling ankle pain.
• A solid fusion provides pain relief and creates stable platigrade
foot.

6. History
• Originally described in 1879 by Albert
– Stabilization of paralytic foot in poliomyelitis
• Charnley developed compression technique in
1951, used an external-fixator
• Arthroscopic arthrodesis described in 1983
• Mini-open arthrodesis described in 1996

7. Indications
• Principle indication is pain, deformity and
instability that is functionally disabling
– Post traumatic arthritis, infection, osteonecrosis,
osteochondral defects, OA, RA, Gout, Charcot
neuropathy, paralytic deformities and failed Total ankle
arthroplasty.
• Absence of normal alignment and arthritis
in the subtalar complex.

8. Contraindications
• Vascular impairment of limb
• Severe osteoporosis
• Skin Infection
• Pre existing ipsilateral hindfoot arthrosis
• Contralateral ankle arthrosis

9. Evaluation
History and Physical Examination
•Careful history for an optimum outcome
•Exact location of pain?
•Examination of ipsilateral Hip and knee joint
•Patients current impairments?
•Functional desires of patient
•Proper counselling
•Assessment of medical comorbidities (peripheral neuropathy, DM,
peripheral vascular disease, Active tobacco addiction)

10. Radiographic Evaluation
• Weight bearing AP and Lateral radiographs obtained.
• Assessment of deformity and planning of correction is
necessary.
• Evaluation of limb length discrepancy is important.
• Hindfoot alignment view can be used for assessing deformity
distal to ankle joint.
• Quality of bone stock and presence of cysts should be checked.
• On lateral view, antero-posterior subluxation of ankle should be
noted as well as any tilt of tibial plafond.
• CT scan can be further helpful in assessment of any defects in
the region of planned fusion.

11. Heel alignment angle
Heel
alignment
ratio = a/ba
b

13. Approaches of Ankle arthrodesis
• Anterior approach
• Antero-lateral approach
• Medial and lateral trans-malleolar approach
• Posterior approach

14. Anterior approach
-anterior aspect of ankle joint.

15. Antero-lateral approach
-medial to fibula and 5 cm proximal to ankle joint.

16. Medial and lateral trans-malleolar approach
-similar to anterolateral approach with better access to
posterior aspect of ankle joint.

17. Posterior approach
-over the lateral margins of achilles tendon.

18. Position of Fusion
• Optimal ankle position is the same
regardless of surgical technique
– Ankle
• Neutral flexion (0o
)
• 5o
- 10o
ER (comparable to contralateral side)
• Slight valgus (5o
)
• Translation of talus posteriorly to align with posterior
margin of tibia

19. Position of Fusion
• Ankle fused in neutral between flexion/extension.
– approximates normal ankle, producing relatively normal
barefoot gait pattern and
– Prevent intractable heel pain.
• Posterior translation of talus under tibia + 5o
of
valgus.
Prevents vaulting type of gait pattern and knee pain.
• ER of 5o
- 10o
, reduces lever arm of the foot.

20. Surgical Options
• Extra articular
– severe osteopenia, pre-existing septic joint
• Intra articular
– significant deformity or malalignment
• Mini-open/Arthroscopic arthrodesis
– minimal deformity

21. Principles of fixation by Mann et
al
• Creation of broad, flat cancellous surfaces
that are placed into opposition to allow fusion.
• Arthrodesis site should be stabilized with rigid
internal or external fixation.
• Hind foot should be aligned to leg and
forefoot should be aligned to hind foot to
create plantigrade foot.

22. External Fixation
• Charnley Method (1951)
First to describe use of external fixator
 Open debridement of ankle joint cartilage via anterior
approach + Ex-fix
 One pin through distal tibia
 One pin through neck of talus
 Use of connecting bars
 But unipolar device did not provide rotational stability
• Compression relies on intact achilles tendon

24. External Fixation
• Calandruccio external fixator
– Triangular compression device.
– Open debridement, external-fixator placed
– 2 Pins through neck and body of talus and 2 Pins through tibia
– Provides additional compression and more rigid fixation.
• Fusion site buttressed with bimalleolar onlay
grafts.

26. Tibiocalcaneal arthrodesis with
a thin-wire & ilizarov external fixation
• Described by Eylon et al.
• Thin-wire fixation to the leg is done, beginning with ring fixators
at the proximal tibia and supramalleolar region.
• A talar half ring is anchored with two wires positioned 50 to 60
degrees from each other through the talar neck and body.
• A calcaneal-forefoot extended half-ring is added and anchored
with wires through the calcaneus and through the metatarsals
• Finally compression is applied.

28. Open Arthrodesis with Internal fixation
• Transfibular (transmalleolar) arthrodesis with fibular strut graft
• Tibiotalocalcaneal arthrodesis
• Posterior approach for arthrodesis of ankle and subtalar joints
• Tibiotalar arthrodesis with a sliding bone graft (blair’s procedure)
• Tibiotalar or tibiotalocalcaneal Fusion with structural allograft
and internal fixation for salvage of failed total ankle arthroplasty

29. Transfibular (transmalleolar)
arthrodesis with fibular strut graft

31. Tibiotalocalcaneal arthrodesis

35. Posterior approach for arthrodesis of
ankle and subtalar joints

37. Tibiotalar arthrodesis with a sliding
bone graft (Blair’s procedure)

38. Tibiotalar or tibiotalocalcaneal Fusion with
structural allograft and internal fixation for
salvage of failed total ankle arthroplasty

40. Open Arthrodesis
• Advantages
– Improved visualization of the joint
– Improved access for bony resection,large correction,
accurate screw placement.
• Disadvantages
– large incisions with significant soft tissue stripping

41. Fixation devices
• Home run screw
– primary stabilizer against doris/plantar flexion forces
• Parallel versus crossed screws
– Two crossed screws create more rigid construct
• Two versus three screws
– Cadaveric studies have shown that three screw
configurations provide increased compression and
resist torque better.

42. Post-operative Care
• Bulky splint maintained for 2 weeks, NWB.
• A short-leg cast is applied, but weight
bearing is not allowed for another 6 weeks,
after which a short-leg walking cast is
applied and is worn until fusion is com-
plete.
• Usually fusion occurs between 8 - 12 weeks
post-operatively.

43. Arthroscopic Arthrodesis
• Indications
<10 degrees of varus and valgus and good bone quality
• Originally described in 1983
– Rate of fusion equivalent to open technique.
• Advantages
– faster time to union
– less blood loss, less morbidity
– faster mobilization
• Disadvantages
– Does not allow for large deformity correction

44. Arthroscopic
• Intra-articular portion of arthrodesis can be
performed using an arthroscope, high speed burr
and currettes
• Arthroscopy performed using 2 or sometimes 3
portals
– anteromedial portal -> medial to tibialis anterior tendon
– anterolateral portal -> lateral to peroneus tertius tendon
– posterolateral portal -> lateral to Achilles tendon, 1-2cm
distal

47. Mini-incision technique
• Originally described in 1996 by Paremain
– utilizes enlarged arthroscopic portals
• Has advantages of both open and
arthroscopic
– decreased soft-tissue dissection
– decreased bone stripping
– quicker radiologic fusion rates
• Disadvantages
– minimal deformity correction

48. Mini-incision technique
• Utilizes two 1.5cm incisions
– medial side
– anterolateral
• Subchondral bone resection with high-speed burr is done along with
bone grafting.
• Ankle positioned appropriately, fixation with cannulated screws done.

49. Anterior tibial
tendon
Peroneus
tertius tendon

51. Triple Arthrodesis
• The most effective stabilizing procedure in the foot, fusion of the
subtalar, calcaneocuboid, and talonavicular joints.
• Edwin Ryerson first described classical triple arthrodesis in
1923 as fusion of all three joints.
• The most common indications were to correct lower limb
deformity in child resulting from polio, cerebral palsy, charcot
marie tooth disease and clubfoot.

52. Principles of classical triple
arthrodesis
• Three joints are exposed and joint resection is done followed by
fixation.
• Resections of mid tarsal joints are usually performed first as it
provides increase soft tissue relaxation and further facilitates
better exposure of the subtalar joints.
• Care should taken to leave as much bone as possible at this
joints specially in valgus deformity because lateral column
length is important for correction.

53. Pre-op planning
• A paper tracing is made from a lateral radio­graph of the ankle,
and the components of the subtalar joint are divided into three
sections :
o Tibiotalar
o Calcaneal components
o Component comprising all the bones of the foot distal to the
midtarsal joint.
• These are reas­sembled with the foot in the corrected position
so that the size and shape of the wedges to be removed can be
measured accurately.

55. Planning
• In talipes equinovarus, a later­ally based subtalar wedge,
combined with midtarsal joint resection, places the talar head
slightly medial to the midline axis of the foot.
• In talipes calcaneocavus, a wedge­shaped or cuneiform section
of bone is removed to allow correction of the cavus deformity,
and a wedge of bone is removed from the subtalar joint to
correct the rotation of the calcaneus.
• In talipes equinovalgus, A medially based wedge consisting of a
portion of the talar head and neck is excised.
• Fixations is done by k­wire or cannulated screws.

56. In talipes equinovarus, a later-ally based subtalar wedge, combined
with midtarsal joint resection, places the talar head slightly medial
to the midline axis of the foot.

57. In talipes calcaneocavus, osteotomy done at dorsal cortex of
navicular and inferior aspect of talar head and neck to allow
correction of the cavus deformity, and a wedge of bone is removed
from the subtalar joint and anterior part of calcaneus to correct the
rotation of the calcaneus.

58. In talipes equinovalgus, A medially based wedge consisting of a
portion of the talar head and neck combined with mid tarsal bone is
excised

60. Complications of Arthrodesis
• Non­union is the most common complication
following ankle arthrodesis.
• Others include
– Infection
– Never injury
– Malunion
– Wound problems
– Lateral instability
– Avascular necrosis of talus

61. • 78 ankle arthrodesis, complications in 44/78
(56%)
– 32 non­unions
– 7 infections
– 2 each: nerve injuries, malunion, wound problems
• Risk factors for non­union
– severe fracture
– open injury
– local infection
– osteonecrosis of the talus
– coexisting major medical problems

62. • Smoking is associated with non­union
– Risk of non­union in smokers is 16 times than that of non­
smokers in absence of other risk factors
• Optimal period of smoking cessation prior to
arthrodesis unknown
– minimum of 1 week suggested empirically

63. Outcomes

64. • 23 patients (11 men, 12 women)
– isolated post­traumatic ankle arthritis
• Mean age at operation
– 41 years (12 ­ 70)
• Mean follow­up duration
– 22 years (12 ­ 44)
• 11 internal fixation, 12 external fixation

65. • 67% satisfied, 88% had no pain.
• More severe OA in ipsilateral adjacent joints
when compared to the contralateral foot was
present
– 91% had moderate­severe subtalar OA
• Significant activity limitation, pain, and
disability on affected side was noted.

66. • Retrospective review of 26 patients who
underwent arthrodesis
• Post­traumatic arthritis in 25/26, primary OA in
the other
• All patients underwent open arthrodesis
– the first 19 with fibular resection for grafting
– remainder fibula retained, fixed to tibia and talus with
compression screws

67. • 77% of patients completely satisfied,19% did
not notice a gait abnormality
• Sagittal plane motion significantly decreased
at hip, hindfoot, and forefoot
– hindfoot and forefoot coronal and transverse plane
motion reduced as well.
• Ankle fusion will relieve pain and improve
function but in the end it’s a salvage
procedure!

68. Thank You