Osteochondral Defect of the Talus

Normal Anatomy

  • The articular cartilage is a smooth, avascular and viscoelastic structure that provides a low coefficient of friction and allows smooth gliding/movement
  • The function of the articular cartilage is also to act a shock absorber as well as allow smooth movement
  • Subchondral bone is the bone underneath articular cartilage
  • Osteochondral – bone and cartilage

Pathology

  • Lesions involving the talar articular cartilage and subchondral bone
  • Compressive and rotational forces crush the subchondral bone and crush/shear the cartilage

Mechanism of Injury

Traumatic

Anterolateral Talus
  • Repeated trauma (chronic instability)
  • Inversion and dorsiflexion injury impacts lateral aspect of talus against articular surface of the fibula
Posteromedial Talus
  • Single trauma
  • Inversion-external rotation and plantarflexion injury impacts the medial aspect of the talus against the articular surface of the tibia

Insidious

  • Congenital factors
  • Ligamentous laxity
  • Necrosis
  • Steroid treatment
  • Single or multiple traumatic events

Classification

  • Multiple classification systems depending on investigation method (X-ray, MRI, CT, Arthroscopy)

Berndt and Harty – X-ray

Stage 1

  • Small subchondral compression fracture

Stage 2

  • Partial avulsion of a fragment

Stage 3

  • Complete avulsion of a fragment without displacement

Stage 4

  • Avulsed fragment displaced within the joint

Associated Pathologies

  • Lateral ligament sprains
  • Fractures

Examination

Subjective

  • Reports a history of trauma, recurrent sprains or instability
  • Deep ankle pain with weight bearing
  • Catching or locking
  • Episodes of swelling

Objective

  • Decreased dorsiflexion with inversion range of motion
  • Lateral lesion - Pain palpation anterolateral joint space in plantarflexion
  • Medial Lesion – Pain palpation posteromedial joint line in dorsiflexion

Further Investigations

  • X-ray
  • CT
  • MRI
  • Arthroscopy

Management

  • Conservative management attempted when stable
  • Surgical intervention most commonly required

Conservative

  • Reduce pain and inflammation
  • Immobilisation and non weight bearing
  • Cast
  • Red
  • Ice
  • Massage
  • Gradual return to weight bearing
  • Restore Normal Range of Movement
  • Ankle, Knee
  • Massage
  • Joint mobilisation
  • Joint manipulation
  • Restore Normal Muscle Activation
  • Evertors
  • Invertors
  • Plantarflexors
  • Dorsiflexors
  • Intrinsic Foot Muscles
  • Restore Dynamic Stability
  • Proprioceptive Training
  • Sport Specific Training

Plan B

  • Surgery
  • Microfracture
  • Osteochondral autografts (own tissue)
  • Osteochondral allograft (someone else’s tissue)

References

(Trousdale, Dahm et al. 2001, McGahan and Pinney 2010, van Dijk, Reilingh et al. 2010, Zengerink, Struijs et al. 2010, van Eekeren, Reilingh et al. 2012, Badekas, Takvorian et al. 2013, Savage-Elliott, Ross et al. 2014)

Badekas, T., M. Takvorian and N. Souras (2013). "Treatment principles for osteochondral lesions in foot and ankle." Int Orthop37(9): 1697-1706.

McGahan, P. J. and S. J. Pinney (2010). "Current concept review: osteochondral lesions of the talus." Foot Ankle Int31(1): 90-101.

Savage-Elliott, I., K. A. Ross, N. A. Smyth, C. D. Murawski and J. G. Kennedy (2014). "Osteochondral lesions of the talus: a current concepts review and evidence-based treatment paradigm." Foot Ankle Spec7(5): 414-422.

Trousdale, R., D. Dahm and J. Manzanares (2001). "Osteochondral Lesions of the Talar Dome." Orthopaedic Surgery7(2).

van Dijk, C. N., M. L. Reilingh, M. Zengerink and C. J. A. van Bergen (2010). Osteochondral defects in the ankle: why painful? Knee Surg Sports Traumatol Arthrosc. Berlin/Heidelberg. 18: 570-580.

van Eekeren, I. C., M. L. Reilingh and C. N. van Dijk (2012). "Rehabilitation and return-to-sports activity after debridement and bone marrow stimulation of osteochondral talar defects." Sports Med42(10): 857-870.

Zengerink, M., P. A. Struijs, J. L. Tol and C. N. van Dijk (2010). "Treatment of osteochondral lesions of the talus: a systematic review." Knee Surg Sports Traumatol Arthrosc18(2): 238-246.

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