What Happens When an Achilles Tendon Ruptures?

By Philip Dripchak, M.D.

There exists a spectrum of diseases involving Achilles tendons, ranging from transient inflammation to a frank rupture. This article will focus on complete ruptures of the Achilles tendon.

The adult Achilles tendon is approximately 15 centimeters long and is the thickest and strongest tendon in the human body. It is formed from the merger of the calf (gastrocnemius and soleus) muscles, roughly at the mid-calf level connecting to the heel bone. The primary function of the soleus muscles is to stabilize the leg on the foot, and the gastrocnemius muscles supply power for jumping, running and walking.

Patients' descriptions at the time of rupture are fairly are consistent. Most will describe a "pop" or sensation that they were "shot" in the back part of the leg or ankle. Several basketball players that I have treated have quickly turned around trying to identify who "kicked" them.

Most patients who rupture an Achilles tendon are males between 30 and 40 years old. Eighty percent of ruptures occur between two to six centimeters above the attachment to the calcaneus (the heel bone). This region corresponds to an area that has been shown as early as the late 1950s to have poor circulation, a so-called "watershed" area. Microscopic studies have further confirmed that ruptures occur through abnormal or degenerative segments of tendon. Interestingly, 85 percent of patients do not seem to experience any painful symptoms prior to rupture.

The clinical diagnosis of a ruptured Achilles tendon is not too difficult. Although several diagnostic techniques involving the use of either needles and/or blood pressure cuffs exist, I typically rely on two clinical signs. If swelling is not significant, a defect in the Achilles tendon can usually be felt. Secondly, the Thompson's test is very useful: With the patient prone or kneeling in a chair, the examiner squeezes the calf. If the foot plantar flexes, that indicates continuity of the tendon. However, if there is no motion of the foot, it usually means it is ruptured. If for any reason the diagnosis is in question, an ultrasound or an MRI can confirm the diagnosis. MRI will also provide information about the quality of the tear.

Once an Achilles rupture is documented, the next decision is whether to conservatively or operatively manage the problem. I feel this decision should in turn be based on several factors: overall health of the patient, condition of the extremity in question (previous scars, burns or pre-existing localized edema) and most important, the patient's actual or anticipated activity level. Non-operative treatment is reasonable for sedentary, physiologically older patients or those who are unable to undergo surgery. A non-operative protocol involves about one month of casting with no weight bearing. Following this, another four weeks of casting with progressive weight bearing is followed by a removable brace and exercises. Before embarking on this route, it is prudent to obtain an ultrasound to document that the torn edges of the Achilles tendon are in close enough proximity to permit healing.

For healthy, active individuals, surgery should be considered. Surgery should always be viewed in terms of risks and benefits. The risks include anesthesia, wound infection, blood clot or possible re-rupture of the tendon. However, surgery will typically allow one to achieve a more functional outcome.

The timing of surgery is approximately one week after the date of injury. This allows swelling to diminish and early organization of the ruptured ends of the tendon. There are essentially two types of surgical techniques. The first is percutaneous (through the skin) repair and the second is an open procedure. I favor the latter because I can ensure direct apposition (the growth of successive layers of a cell wall) of the tendon and placement of secure sutures to permit an aggressive rehab program. If there is any tension on the wound edges during closure, I will perform a posterior fasciotomy to minimize wound complications.

Open surgical repair permits earlier motion and rehab because of the secure fixation of the tendon. Laboratory studies and clinical studies from our colleagues in hand surgery have demonstrated that early controlled motion after tendon injury optimizes the patient's outcome, because of increased tendon strength, decreased muscle atrophy and increased tendon mobility.

If surgery is performed in a timely fashion, it is usually straightforward and takes less than one hour. However, Achilles ruptures that are neglected or diagnosed late pose a significant reconstructive challenge. With the passage of time, the gap between the edges of the tendon increases, making it impossible to pull them "back together." This necessitates a tendon transfer from the foot, either alone or in conjunction with a myotendinous lengthening of the gastrocnemius. The complexity of the procedure adds to the risk and the recovery time for the patient.

Achilles ruptures can be managed either non-operatively or surgically. Because surgery allows secure fixation of the tendon edges, motion and rehab can commence sooner which optimizes a functional outcome for the patient.

Dr. Dripchak is a board-certified orthopedic surgeon who has been in practice since 1992. He completed a foot and ankle fellowship at University of Texas Southwestern in Dallas . Dr. Dripchak received his orthopedic training at Emory University in Atlanta, Georgia. He may be contacted at Bluegrass Orthopedic Group, 502-367-1744.