Foot and Ankle Trauma: Foot and Ankle Contusions
Normal Anatomy
The bones of the ankle are the tibia (shin bone on the inside of the ankle), fibula (small shin bone on the outside of the ankle) and the talus (bone at the top of the foot). The tibia, fibula and talus meet to form a complex hinge that does move to a mild degree towards the inside and outside, as well as rotates clockwise and counter-clockwise. There are many small bones in the foot arranged in a similar arrangement to those in the hand/wrist. The bones in the hindfoot and midfoot provide stability.
Three bones of the ankle are surrounded by a thick layer of cartilage in the ankle joint and are held together by the ankle joint capsule, which supports, nourishes, and helps stabilize the ankle joint. In addition to the bony architecture of the ankle, ligaments hold the ankle together and give it stability and allow the ankle to function as a unit as it responds to the forces acted upon by the muscles about the leg. The ligaments on the inside and outside of the ankle limit excessive sideways motion of the ankle preventing a dislocation of unexpected forces move the foot in the wrong direction as occurs when someone trips or falls.
Tendons that arise from the three compartments of the leg span the ankle joint to attach to the foot. There are three main muscles on the front of the leg whose tendons cross the ankle to attach onto the foot and are responsible for bringing the foot up. The calf muscles in the back of the leg attach to the back of the heel bone (calcaneous) through the Achilles’ tendon. There is one main muscle on the inside of the leg called the Tibialis Posterior that becomes a tendon at or near the level of the ankle that inserts onto the foot and is responsible for turning the foot inward towards the big toe. There are two main muscles on the outside of the leg that become tendons at or near the level of the ankle that inserts onto the foot that pulls the foot outwards towards the small toe.
Pathology
Trauma is the term used to describe injury. Trauma is classified by its severity depending on the amount of force used to cause the injury. Trauma is also distinguished according to whether it is caused by a single major force or minor repetitive, smaller forces which are cumulative (additive) over time. This is referred to as Cumulative Trauma Disorder (CTD). An injury is also classified depending on if the skin was breached, called an open injury or the skin layer stays intact, referred to as a closed injury. When an injury is minor, it is called a contusion and in this instance, it implies that the injury was closed and only involves the soft tissues including the skin, subcutaneous tissue, muscles, tendons, ligaments, arteries and nerves, alone or in combination. In a contusion, the soft tissue is bruised or stretched, but not torn and requires only symptomatic treatment. The same force of trauma sustained by different patients will result in different injury severity because changes that occur in our body’s internal structure with aging. Specific changes occurring with aging is the amount and type of collagen in our body through metabolism is converted from Type I collagen which is the typical collagen most often found in the human body is converted into Type II collagen. Type II collagen is less resilient and is the type of collagen found in healing scar. The protein, elastin, which gives tissue its stretch properties, also decreases in content with aging. Finally, the water content in the cells of the body decrease with aging. Below is a graph that depicts an identical force sustained by individuals at different ages divided into 20-year increments and the time it takes for each group to heal and become symptom-free. The white section is when the patient is symptom-free and the yellow section is when the patient is having symptoms including pain, stiffness, weakness, and poor function. Note the curve does not come back to baseline and shifts to the right with aging.
Treatment
The most common symptomatic treatment used for all types of soft tissue injuries has three approaches: 1. R.I.C.E. treatment, 2. Anti-inflammatory treatment 3. Controlled early motion and therapy.
The acronym RICE stands for Rest, ice, compression and elevation. Rest is usually done for 24-48 hours, and can include the use of slings, splints or other types of immobilizers unless otherwise advised by a physician. Ice is used for no more than 20-30 minutes at a time, three to four times per day. Ice is best applied by using an ice slush which transmits the effects of the cold sensation best and can be made by crushing ice and mixing it with water and then placing it in a zip lock plastic bag. The ice bag should not be placed in direct contact with the skin but instead should have a layer between the skin and ice bag like a towel to prevent the skin from freezing. The ice should be applied for no more than 20-30 minutes to avoid skin freezing as can occur if you fall asleep with an ice pack on your limb. Ice functions by causing the arteries to narrow the size of their lumen which in turn decreases swelling and the pain from swelling.
Compression is the wrapping of a body part to further assist in minimizing swelling and is used in conjunction with elevation. The best way to do a compressive wrapping is by having the compression have multiple layers that provide a cushion effect. The compression should be wrapped without causing the constriction of the blood supply which is recognized by increasing pain to the body part wrapped. Other signs of a tight compressive dressing are the cold sensation of the wrapped limb, blue discoloration of the body part, or change in color from the natural skin color. Elevation of an injured body part is best done by elevating the limb to the level of the heart. If elevation is lower than this, the effects of gravity on the veins, will increase vein pressure and cause the blood in these veins to have difficulty traveling back to the heart and result in limb swelling.
The use of anti-inflammatory medication helps treat the pain, swelling, and inflammation that occurs after injury is imparted on a limb. Examples of anti-inflammatories includes aspirin products, Ibuprofen (Motrin® and Advil®), Naproxen (Aleve® and Naprosyn®), Mobic®, Indocin®, Arthrotec®, and Celebrex® to name a few. All of these medications have side effects and should be taken with this knowledge in mind. Prescriptions should be discussed with your pharmacist and physician.
Controlled early motion and therapy to the involved limb decreases the effects of prolonged immobilization which includes stiffness, muscle atrophy, weakness and a longer return to the pre-injury state. The type of therapy recommended will depend on the tissue type injured and the severity of this injury. Consult your surgeon for the best advice.