The talocrural (ankle) joint is the junction of three bones: distal ends of tibia and fibular and the talus trochlear

The tibia and fibular are bound by the ligamentous structures that include the syndesmosis, anterior/posterior/transverse tibiofibular ligaments.

Collateral ligaments include the anterior and posterior fibulotalar ligaments, fibulocalcanear on the lateral side while the medial side is supported by the deltoid ligament and calcaneonavicular ligaments.

The ankle joint is not a pure hinge joint as there is some rotation around the helical axis of the joint due to the asymmetrical shape of the talus.

Precise ankle joint congruence is important for load distribution of the compressive forces across the joint.

Causes:

Primary:

• Ankle joint arthritis, unlike the hip and knee joints, is rarely primarily affected

Secondary:

• Inflammatory conditions: Rheumatoid arthritis, gout
• Bleeding disorders: haemophilia
• Ischaemia: Avascular necrosis of the talus
• Neuoropathic: Charcot arthropathy
• Tendon dysfunction: Tibialis posterior tendon dysfunction
• Post traumatic: previous ankle fracture/ligament tears

Presentation:

• Pain
• Swelling
• Deformity
• Inability to walk with pain that worsens with standing or walking
• Multiple joint arthralgia when cause due to an inflammatory cause

Clinically:

• Ankle swelling
• Joint tenderness
• Crepitations
• Positive talar shift
• Muscle atrophy
• Decrease ankle joint range of motion
• Assess and exclude systemic inflammatory cause

With worsening ankle joint degeneration and ankylosis ankle ROM decreases

Bleeding inside ankle joint

Investigations:

• X-ray:
  Ankle and foot: Standing AP, Lateral & oblique.

X-rays Findings

• Joint space narrowing, sclerosis, osteophytes
• In RA assess for periarticular joint cysts and osteopenia

CT: useful for surgical planning.

MRI: useful to evaluate soft tissue injuries and cartilage damage especially when early in the disease process and to assess Tibialis posterior dysfunction.

Topical ankle joint injection

Ankle joint replacement

Ankle fusion

Optimal position:

• Neutral dorsiflexion
• 5-10° external rotation
• 5°hindfoot valgus
• 5 mm posterior talar translation

Other ankle joint fusion surgery fixation options include:

• • Plate & screw fixation
  • Nail & screw fixation
  • Arthroscopic assisted ankle joint fusion

Ankle arthroscopy technique:

This surgery technique can assist with arthroscopic ankle fusion

Post surgery arthrodesis:

• Splint in backslab Plaster of Paris (POP) for soft tissue swelling to subside with 2 weeks non weight bearing (NWB)
• Remove sutures after 10 days and then continue full POP with NWB for another 4 weeks
• Follow up: Boot application with partial to full weight bearing X 4-6 weeks
• Physiotherapy

Post ankle joint replacement:

• Allow soft tissue swelling to subside in backslab POP non weight bearing
• Remove sutures after 10 days and then boot with partial weight bearing 4 weeks
• Follow up again, then partial/full weight bearing
• Physiotherapy

After ankle joint replacement ankle ROM

Foot strengthening exercise after union

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      2. Ankle arthritis- an important signpost in rheumatologic practice. PDW Kiely, ME Lloyd. Rheumatology 2021 Jan;60(1): 23-33.
      3. Ankle arthrodesis: A systematic approach and review of the literature. Y Yasui, CP Hannon, D Seow, JG Kennedy. World J Orthop 2016 Nov 18;7(11): 700-708.
      4. Arthroscopic ankle arthrodesis. B Hutchinson. Clin Podiatr Med Surg 2016 Oct;33(4): 581-9.