Syndesmosis Injuries – Diagnosis, Management and Rehab
Sports and Exercise Medicine
Syndesmosis Injuries
Diagnosis, Management and Rehab
o Syndesmosis injury – also known as “high ankle sprain”
o 0.5% of all ankle sprains without fracture
o 13% with ankle fracture
o Mechanism - external rotation, eversion injury
- External rotation forces talus laterally, pushes fibula away from the tibia.
- Leads to increased forces within the tibio-talar joint.
- Stresses ligamentous complexes, congruence of ankle joint, subluxation of the fibula
Diagnosis
o Associated injury
- osteochondral defect (up to 25%), Peroneal injury (up to 25%), fractures
- Weber B/C, occult fracture (base 5th metatarsal, anterior calcaneal process, lateral talar process)
o Watch for deltoid ligament injury - deep and superficial fibres, avulsion fracture
o Missed injuries - ongoing pain, accelerated OA
o If treated promptly excellent functional outcomes
Anatomy
- Syndesmosis – several ligaments
- AITFL (anterior-inferior tibiofibular ligament)
- PITFL (posterior-inferior tibiofibular ligament) – strongest part
- Interosseous membrane
- Interosseous ligament (distal part of interosseous membrane)
- Inferior transverse ligament
(fig1)
- Function
- maintains integrity between tibia and fibula
- resists axial, rotational and translation forces
Presentation
-
Symptoms
- Anterolateral ankle pain
- Medial ankle pain if deltoid ligament involved
- Swelling - globally throughout the ankle
- Pain weight bearing
-
Examination
- Tender syndesmosis and along interosseous membrane - the higher the tenderness, the worse the prognosis
- External rotation with dorsiflexion in prone position and bent knee - unable to maintain knee in mid-line
- Pain on squeeze testing – when squeezing together tibia and fibula at midshaft level, referred pain at the syndesmosis is experienced.
- Pain on heel raise, inability to heel raise
Scans
-
X-ray
- Weight bearing “Mortise” view
- Visualise the opening of the syndesmosis, may need comparison views
-
MRI
- Considered gold standard
- AITFL, PITFL easily visualised. Highly sensitive and specific (fig 2 and table 1)
Management
- Depends on injury grade as per Modified West Point Classification.
- Grade I: Sprain AITFL, no instability or diastasis
- Grade II: Sprain AITFL / IOL, mild instability / no frank diastasis
- IIA: Normal deltoid, Negative squeeze test
- IIB: Injured deltoid, positive squeeze test.
- Grade III: Complete tear, frank instability and diastasis
- Non-operative for Grades I-IIA, Operative for Grades IIB-III
- Grades I-IIA
– Progressive rehabilitation. Return to sports @6 weeks
-
- Grades IIB-III
– Arthroscopic assessment +/- stabilization. RTS @9 weeks
Surgical Techniques
- Arthroscopic assessment – When unstable, stabilisation of syndesmosis (Screw / Suture-button) +/- syndesmotic ligaments repair +/- deltoid repair.
- In chronic injuries (>3 months) – Ligament reconstruction (Tendon autograft)
- If syndesmotic OA established (and low-demand) – Syndesmotic arthrodesis
Rehabilitation Protocols
- Surgical stabilisation - period of immobilisation and restricted weight-bearing
- Progressing to restoration of range of movement, strength and proprioception
- Eventually sports-specific drills become the focus prior to return to competition.
- Conservative management
- Significant syndesmosis injuries can also be successful
- Carefully selected following MDT discussions
- Number of factors including function, imaging, sport and often ‘time of season’ and age of player
- Detail of rehabilitation protocols can differ but the outline framework below gives an insight into the goals of each stage.
Authors
- Dr Kal Parmar
- Mr Francesc Malagelada
- Colin Lewin - https://www.lewinclinic.co.uk/
Twitter @LewinPhysio - Instagram @thelewinclinic
Sources
- https://synapse.koreamed.org/ViewImage.php?Type=F&aid=109274&id=F1&afn=120_JKFAS_22_4_145&fn=jkfas-22-145-g001_0120JKFAS
- https://www.aspetar.com/journal/upload/PDF/2014127152113.pdf