Medial ankle ligament

 Medial Ankle ligament

Introduction

The deltoid ligament (or medial ligament of talocrural joint) is a strong, flat, triangular band, attached, above, to the apex and anterior and posterior borders of the medial malleolus. The deltoid ligament is composed of the anterior tibiotalar ligament, tibiocalcaneal ligament, posterior tibiotalar ligament and the tibionavicular ligament. It consists of two sets of fibers, superficial and deep.

Anatomy and Function

Medial side of ankle is stabilized by deltoid ligament, which always has: tibionavicular, tibiospring/tibiocalcaneal, and deep posterior tibiotalar ligaments.

Clinically Relevant Anatomy

The stability of the ankle is provided by the medial and lateral collateral ligaments and the syndesmosis. The medial ligament complex consists of wide flared, strong connections, which combine to form the lig. Deltoideum. The hardly stretchable medial structures also provide passive stability of the foot and the reception of large forces acting on the footing.

The deltoid ligament, also known as the medial collateral ligament of the ankle, attaches the medial malleolus to multiple tarsal bones. Unlike the superficial layer of this ligament, the deep layer is intraarticular and is covered by synovium. The superficial components include the tibiocalcaneal ligament, tibionavicular ligament, posterior superficial tibiotalar ligament, and tibiospring ligament; the deep layer components include the anterior tibiotalar ligament (ATTL) and the posterior deep tibiotalar ligament (PDTL). Anatomically, in general, the superficial components arise from the anterior colliculus of the medial malleolus, and the deep components arise from the intercollicular groove (malleolar groove) and the posterior colliculus of the medial malleolus.

Medial ankle stability is provided by the strong deltoid ligament, the anterior tibiofibular ligament and the bony mortise (Figure). Because of the bony articulation between the medial malleolus and the talus, medial ankle sprains are less common than lateral sprains. In medialankle sprains, the mechanism of injury is excessive eversion and dorsiflexion. (level of evidence 3A)
(level of evidence 3A)
Isolated deltoid ligament injuries are extremely rare and usually occur in combination with fractures of the lateral malleolus. These are treated by recognizing the injury complex and stabilizing the lateral side, being sure that the mortise is reduced.

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 Examination

Eversion Test-
In neutral evaluates superficial deltoid ligament complex.
External rotation stress test evaluates syndesmotic ligaments and additionally - the deep deltoid ligament;

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;
- 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 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

Physical Therapy Management

To avoid ankle sprains, or ankle instabilities we have exercises to enforce or train the medial ligaments of theankle. Those ligaments are important to avoid an eversion of the ankle (eversion trauma’s). Otherwise we have exercises that are used after ankle sprains or ankle instability.

First and second degree sprains are typically managed with conservative treatment. This conservative treatment consists in de early stages of RICE (rest, ice, compress, elevate) and mobilization to prevent range of motion loss. When pain and inflammation are controlled, we can start with therapeutic exercises to increase the range of motion stability, strength proprioception and function.

For the third degree there has to be surgical treatment to resolve the structural damage. After this surgery, the ankle is immobilized. If there is pain or oedema after the immobilization, this has to be treated first before starting the conservative treatment, which is the same as for the first and second degree.

After two weeks when started physiotherapy, we can give strengthening exercises for the medial muscles and ligaments of the ankle. The first exercise, the subject had to sit on a chair or massage table with his leg extended. The physiotherapist held the leg in his one hand just below the knee. In his other hand he held the lateral side of theankle. The physiotherapist moved the foot to inversion, and gave some manual resistance. The subject had to perform an eversion, against this resistance. The physiotherapist held the resistance for 3 to 5 seconds. The exercise had to be repeated for 10 to 12 times. (level of evidence 2A)

This exercise can also be done without the resistance of a physiotherapist. The subject takes place on a chair. He puts an elastic tubing around his foot, and puts his other foot on the elastic tubing. He holds the elastic tubing in his contralateral hand. Then he has to perform the same exercise as with the therapist. He has to push his foot outward, with his footpad away from the midline of his body.

We can start exercises for proprioception after 5 weeks when started physiotherapy.
Exercise for training the proprioception, the double-leg right/left condition, the subjects had to sit on a chair, with their feet on a kinaesthetic ankle board. They had to keep their knees at a 90° angle, while maintaining contact with the top of the KAB with their respective extremities. Then they had to rotate the board to the left side and then back to the right (=clockwise and counter clockwise). The subjects had to keep the side of the board in the floor each time they moved the board to the left or the right. Each exercise had to be done 3x25 times. (level of evidence 2B)

The next exercise had to be done in stance. First they had to stand flat floor and then on a balance board. The subjects had to stand on one leg on the floor, first with their eyes open and thereafter with their eyes closed. Each exercise had to be done 3x15 times. After this exercise the subject had to stand with both feet on a balance board or wobble board. They had to make circular movements to train eversion, but also inversion, dorsiflexion and plantar flexion.

The next exercise was the same as the first one, but now the subject had to stand on the balance board. They were instructed to stand on one leg in the middle of the balance board, and then they had to maintain the stance on the balance board. First they had to do it with their eyes open, thereafter with their eyes closed. Each exercise was performed during 30 seconds. (level of evidence 2B)  

To make these exercises more difficult we could vary the surfaces, on the floor, a balance board, and an instable underground. Another way to increase the difficulty was to open or close the eyes while performing the exercises. The physiotherapist could also increase the exercise by giving light perturbations while the subject balanced on the balance board.

Key Research

add links and reviews of high quality evidence here (case studies should be added on new pages using the case study template)

Resources

1. http://www.wheelessonline.com/ortho/deltoid_ligament

Clinical Bottom Line

add text here