The Achilles tendon is the strongest and largest tendon in the human body. It is formed by the gastrocnemius and soleus muscles (calf), and inserts in a broad fashion into the back of the heel (calcaneus). The primary function of this muscle-tendon unit is to provide powerful propulsion in waling or running or powerful jumping.

The blood supply to the mid-portion of the tendon is poor, making the tendon susceptible to injury. Injuries may be in the form of inflammation to the tendon covering (paratenonitis), disease of the tendon (tendinosis), spurring at the heel (insertional spurs with tendinitis) and partial or complete ruptures of the Achilles tendon.

Susceptibility to this injury in the work place can often be predicted. A tendon will become inflamed (tendinitis) if excessive load is placed upon it. This may occur in a worker who is constantly going up and down on their toes to reach for something when they are not accustomed to it or climbing up and down a ladder too frequently in a short period of time. It may also occur if the worker has to push heavy items, walks excessively up an incline or jumps up and down too frequently in a short period of time. We often see it in weekend athletes or joggers who try to get into shape too quickly and do not stretch. Tightness in the Achilles tendon makes one more susceptible to these injuries and poor shoe wear may contribute to this as well.

Ruptures of the tendon, complete or partial, may occur when a worker or athlete suddenly moves the foot up (dorsiflexion), such as when slipping on a stair or stepping quickly. It may also occur if the front of the foot moves violently up, putting extreme stress on the tendon. The tendon tears just as a rope would if the ends of the rope are pulled apart. Tendinitis may weaken the tendon, making it more susceptible to rupturing. Tendonitis may often precede weeks or months before the tear.

Stiffness and pain in the Achilles tendon after getting out of bed in the morning or after sitting for a short period of time is the most common complaint. As the person walks the pain and stiffness will often diminish as the tendon stretches and the blood supply to the area improves. As the condition worsens, the stiffness and pain last longer in the morning and burning and discomfort develop with excessive weight bearing. Occasionally, swelling or a crackling sensation may be felt in the back of the Achilles tendon or heel area.

When tendinitis develops, treatment should be aimed at reducing the inflammation and changing the work status or activity of the person to avoid chronic conditions and tendon ruptures. Job and activity descriptions that include more sitting, less pushing, less reaching and less walking will often allow the tendon to rest until the inflammation subsides. Heel lifts, oral inflammatories (non-steroidal), ice, physical therapy, avoiding walking barefoot, and occasionally a day or night splint is beneficial. Once the acute inflammation subsides, stretching will often stimulate flexibility, decreasing the likelihood of recurrence. Depending on the severity, it may last one to eight weeks. If symptoms do not reduce, immobilization in a CAM walker or cast may be necessary.

Ruptures of the Achilles tendon should be treated surgically on most occasions. Cleaning the frayed edges of the tendon and reapproximating the edges is treatment of choice. Postoperative immobilization is necessary to avoid stress on the area and may last one to twelve weeks. The patient will be nonweightbearing, on crutches, for at least six weeks. The patient should be able to be able to resume sedentary work, such as desk jobs, approximately one week after surgery. The leg will need to be elevated, but little risk of complications will be present by early return to work.

 Physical therapy is performed when the leg comes out of the cast, and may be necessary for 2 to 6 months. Excellent results are often achieved with reapproximating the tendon ends. In a high-risk patient (i.e. diabetes mellitus or peripheral vascular disease), conservative treatment is performed, which would consist of cast immobilization for 8 to 12 weeks to allow scar tissue to reapproximate the tendon. Full return to activity may take 4-12 months.