- See:
Deltoid Ligament Injuries due to Ankle Fractures:
- Anatomy and Function:
- medial side of
Ankle Joint is stabilized by deltoid ligament, which has two major components;
-
superficial deltoid:
- originates from anterior & inferior aspects of
medial malleolus fanning out & sending 3 bands to navicular
and along plantar calcaneonavicular (spring) ligament, to sustenaculum tali of calcaneus, & to medial tubercle;
- superficial deltoid lig primarily resists eversion of hindfoot;
- tibionavicular portion suspends spring lig & prevents inward displacement of head of talus, while tibiocalcaneal portion
prevents valgus displacement.
- superficial deltoid is also partially covered by tendon sheaths & crural fascia;
-
deep deltoid ligament:
- originates on posterior border of anterior colliculus, intercollicular groove, & posterior colliculus;
- it is oriented transversely & inserts into entire nonarticular surface of medial talus;
- deep deltoid extends function of
medial malleolus & prevents lateral displacement of talus & prevents external rotation of the talus;
- latter effect is pronounced in plantar flexion, when deep deltoid tends to pull talus into internal rotation;
- originates from inferior & posterior aspects of
medial malleolus and inserts on medial and posteromedial aspects of the talus;
- Physical Exam:
- eversion test;
- in neutral evaluates superficial deltoid ligament complex;
- external rotation stress test evaluates
syndesmotic ligaments and additionally - the deep deltoid ligament;
- Fractures w/ Deloid Injury:
- see:
deltoid ligament injuries due to ankle fractures:
- in absence of a medial malleolar fracture deltoid ligament may be stretched or torn in all oblique frx of fibula;
- this ligament prevents
posterior tibial tendon from slipping into
Ankle Joint;
- ligament ultimately heals in a lengthen position;
- these patients are often diagnosed as having chronic deltoid sprains;
- main problem, however, is lateral talar shift resulting from malunited frx of lateral malleolus or a
syndesmotic ligament injury, which widens mortise &
produces chronic ankle instability;
- Radiographic Diagnosis of Injury:
- deloid is usually avulsed from tibial attachment, frequently w/ small flake of bone visible on x-rays;
- disruption of deltoid ligament can be dxed w/ relative confidence when
medial clear space between talus & med malleolus is increased;
- there is usually assoc lateral shift of talus, w/ incr medial joint space ( > 3 mm), but this may be apparent only on stress view or in postcasting films,
after the swelling has subsided;
- presence of medial tenderness & > 5 mm of space is seen then there is substantial injury of deltoid ligament;
- Treatment of Deltoid Tear:
- such injuries should be rxed as bimalleolar frx, w/ ORIF of
lateral malleolus;
- routine exploration of medial side of ankle is not necessary unless there is evidence that portion of deltoid lig has entered joint & is blocking reduction of talus;
Fractures of the distal part of the fibula with associated disruption of the deltoid ligament. Treatment without repair of the deltoid ligament.
The deltoid ligament. An evaluation of need for surgical repair.
The medial collateral lilgaments of the human ankle joint: anatomical variations. CE Milner and RW Soames. Foot and Ankle Internation. Vol 19. No 5. May 1998. 289.
