What is an Achilles tendon tear?

The Achilles tendon is a large tendon at the back of the lower leg and ankle that connects the calf muscles to the heel. It is the largest tendon in the body and its strength allows us to push off with forces up to 10 times our body weight. A tear, or rupture, usually is a complete gap between the upper and lower portions of this tendon. It most often occurs 2-3 inches above the heel bone but can be directly at the attachment or higher in the leg.


A tear usually occurs during activities such as running and jumping,d or trauma such as a slip and fall. Most patients report their first feeling was a "pop" or that they were struck in the back of the ankle, followed by some pain. There often is no pain in this area before the actual tear. After the tear, patients complain of weakness when pushing off of their foot during walking or when trying to stand on tiptoe. There may be a small bruise on the inside of the heel during the first few days.


The causes of an Achilles tendon tear are not well-known. Risk factors include a high arch, obesity, diabetes, rheumatoid arthritis, errors in training, steroid usage, Quinolone antibiotics usage and aging related changes in tendon stretchability.


Your foot and ankle orthopaedic surgeon typically performs an examination to make a diagnosis. You will lie in a facedown position with your ankles off the edge of the exam table. An intact tendon will be taut and therefore the ankle will usually lie in a toe down position of approximately 20 degrees. The torn side will not have this tension and the ankle usually will hang at about a 90-degree angle. Squeezing the upper calf of a normal ankle will cause the toes to point down even further. The torn side will have weak or no such movement. Light pinching of the Achilles tendon 2-3 inches above the heel often will identify a gap. Special tests such as ultrasound, X-rays and MRI scans usually are not helpful but can be in some instances.


At first, the leg is placed at rest in a splint or special boot. It is important to see a foot and ankle orthopaedic surgeon soon after the injury so the best treatment can be started within a few days.

Both non-surgical and surgical treatments have been well studied but remain debated. In general, surgical treatment is thought to give greater strength and result in a lower risk of repeat tear. However, surgery has an increase in the risks of wound healing problems, nerve damage, and infection plus the usual risks associated with surgery. Blood clots are a concern with both types of treatment. Your surgeon will be the best person to guide you through the pros and cons and help you to select the best option.

Non-surgical treatment starts with a period of rest in a brace for the injured leg. The patient will need to use crutches, a walker, or wheelchair in order to not put weight on the leg. Within the first few weeks the patient will start doing active motion. The brace will be adjusted over time as the Achilles tendon heals to allow increased movement. Gradually, the patient will be allowed to put weight on the leg and start specific strengthening exercises. The length of treatment may be different for each patient but usually takes about three months. It is often guided by a physical therapist along with the orthopaedist.

Surgical treatment is done by placing stitches into the tendon above and below the area of the tear and then pulling the ends together. This is because the actual tear appears similar to two wet mops with multiple uneven strands that need to be brought together. The stitches can be applied through one or more incisions (viewing the tendon directly) or through multiple small incisions (placing the sutures through the tendon using a guide). The recovery after surgery is similar to the non-surgical treatment but can be slightly shorter.


Tendons do not have a great blood supply and healing is a slow process. Patients usually can start light jogging in 3-6 months with return to sports involving cutting and jumping in 6-9 months. Full return of strength and the feeling of being normal may take more than a year.


Is there anything that can be done to prevent tearing the Achilles tendon?
Achilles tendon tears occur so rarely that there is no study that really answers this question well. A stretching program for the Achilles tendon makes sense but the benefit has not been well shown. That being said, there is no downside to stretching the tendon and it should be part of every athlete's warm up. The negative effects of cigarettes on tendon health have been well shown and smoking should be avoided.

How likely is a patient to tear the other side?
About 6 percent of patients with an Achilles tendon tear will have the same injury in the other foot.

Is there anything that can be done to make the tendon heal faster?
Starting range-of-motion exercises and putting weight on the injured leg early have shown better results than long periods of immobilization on crutches but has to be balanced by the risk of pulling apart the ends of the tendon if too much stretch is applied too early. Stopping smoking for at least a few months while the tendon heals also is likely to be of benefit.


Original article by F. Ray Nickel, MD

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