Article > Foot & Ankle > Ankle Sprain

Ankle Ligament Injuries

At various joints throughout the body, bands of connective tissue called ligaments function to hold these joints together. These ligaments create stability, but also allow for normal joint mobility. A sprain refers to the injury of a ligament, which can vary from very mild to severe. The most common grading system for sprains is as follows:

• Grade I: the ligament is stretched, but not torn. There may be minimal swelling and some pain. Generally, return to activity is within 2 weeks.
• Grade II: the ligament is partially torn, and some bleeding from the ligament may occur. This can lead to bruising within a few days, but the location of the bruising does not have to correspond with the location of the injury. This is due partly to the effect of gravity, causing the blood to pool in the tissues near the heel or at the toes. Swelling and pain are more considerable than in a grade I sprain. Return to activity is usually between 2 - 6 weeks.
• Grade III: the ligament is completely (or very near to completely) torn. Swelling and pain may be quite severe initially. After a few days, the pain may improve considerably because the ligament is severed, and isn't under constant stress (as in a grade II sprain). Depending on the location of the sprain, and the level of activity of the individual, surgery may or may not be required. Return to activity may exceed 6 weeks.

Furthermore, it may take up to 6 - 12 months to fully recover from a ligament injury. During this time the fibers within the ligament continue to remodel and strengthen. This slower healing time is due, in part, to the low blood supply of ligaments in general.

ANATOMY

At the ankle, there are many joints and ligaments that may be affected. We will discuss the anatomy of the more commonly injured joints here, keeping in mind that other aspects have been overlooked or simplified.

The two bones of the lower leg (the tibia and fibula) form the bony protrusions on the inside and outside of the ankle. These "bumps" are called the medial and lateral malleoli. In between these malleoli, at the very center of the ankle is a bone called the talus. The joint formed by the talus and the above tibia/fibula complex is what people commonly call the ankle joint. This joint allows the basic up and down movement of the foot. Ligaments on either side of the joint provide stability against medial and lateral (inwards and outwards) movement. The medial (inner) collateral ligament is made up of a few different ligaments and is stressed when the foot is rolled or "twisted" outwards. This ligament is quite strong, and when stressed it may actually tear the end off (ie: fracture) the medial malleoulus. The outer aspect of the ankle joint has three main ligaments that provide stability against inwards movement of the foot. The names, however unimportant, of these lateral ligaments are the anterior talofibular, calcaneofibular and posterior talofibular ligaments. When the foot is "twisted" inwards, these ligaments may be sprained. Most ankle sprains affect these ligaments, particularly the anterior talofibular.

Aside from the "ankle joint", the talus also shares joints with the rest of the foot. Behind the talus, it attaches to the calcaneus (heel bone). This is called the subtalar joint, and provides most of the inwards and outwards movement of the foot. Some of the ligaments that provide stability to the subtalar joint reside deep within the foot. Sprains to these ligaments here may easily be overlooked, since the pain may be deeper and more difficult to localize. The subtalar joint is very important in weight-bearing activities (walking, biking, etc..), so proper care and attention should be given if this joint is affected.

In front of the talus, there are joints attaching it to the midfoot (middle of the foot). The ligaments at these, and the rest of the foot's joints, are less commonly injured.

FACTORS

As mentioned above, the injury occurs when certain ligaments are stressed beyond their limits. Inwards or outwards twisting of the ankle will lead to lateral or medial ligaments being stressed, respectively. If there is a large enough rotational component to the twisting force, injury to other ligaments (such as those of the subtalar joint) may result.

Aside from the mechanism of injury, other factors may increase the chances of suffering a ligament sprain as well. Inadequate warmup prior to an activity may ill-prepare the ligament (among other structures) for stresses. This is an important note pertaining to many of the body's soft tissue structures.

A major preventative factor is the mere skill level or prowess of the individual. This is related to safe, controlled movement during the activity, which may decrease the likelihood of being caught in a compromising position.

In addition to the mechanism of injury, other external factors exist. The physical environment in which the activity is performed, and the type of protective equipment used, can both influence the chances of sustaining injury. For example, trail running may increase the risk of an ankle sprain (although it generally inflicts less wear on the joints when compared to street-running). With regards to equipment, improperly fitted footwear can decrease the stability, therefore increase the risk of ankle sprain.

PHYSIOTHERAPY TREATMENT

As each injury is unique with respect to the structures involved, the extent of damage, and the biomechanics of the individual, it is very difficult to discuss the physical therapy management fairly. General mamagement guidelines for soft tissue injuries during the early acute phase, go to the Injury Care page. It also mentions the various treatment choices that may be employed by your physical therapist.

The specific treatment should be based on a full assessment, which should include a detailed history, a full functional assessment of the injured area, a biomechanical analysis of the whole person (includes posture, movement patterns, etc...) and screening for more serious pathology.