Summary
Achilles tendon ruptures commonly occur in athletic individuals in their 30s and 40s while performing activities that require sudden changes in direction (ex. basketball, tennis, etc.). Patients usually describe a sharp pain in their heel region almost as if they were “struck in the back of the leg”. The diagnosis of an acute Achilles tendon rupture is made on clinical examination as x-rays will reveal the ankle bones to be normal. The Achilles is the largest and strongest tendon in the body (figure 1). It is subject to 2-3 times body weight during normal walking so regaining normal Achilles tendon function is critical. Achilles tendon ruptures can be successfully treated non-operatively, or operatively, but they must be treated. Surgical treatment leads to a faster recovery and a lower rate of re-rupture. However, surgery can be associated with very serious complications such as an infection or wound healing problems. For this reason non-operative treatment may be preferable in many individuals, especially those patients with diabetes, vascular disease, and those who are long-term smokers.
Figure 1: Achilles Tendon
Clinical Presentation
The Achilles Tendon is the largest and strongest tendon in the body (Figure 1). It functions to help control the foot when walking and running. Ruptures of the Achilles tendon commonly occur in individuals in their 30s and 40s. These ruptures commonly occur when an athlete who has a sudden change of direction feels a sharp pain in the back of their heel (Figure 2). Patients often initially think that they were “struck in the back of the heel” and then realize that there was no one around them. These ruptures occur as the calf muscle generates tremendous force through the Achilles tendon in the process of changing direction. It more commonly occurs in patients that are in their 30s, 40s and 50 than in younger patients. This is due to an apparent correlation with tendon degeneration leading to weakening. After the injury, patients will have some swelling. If they can walk at all, it will be with a marked limp. The rupture of the Achilles defunctions the calf muscle, which is the main muscle used for walking and running (Figure 3). It is very rare that a rupture of the Achilles is partial. However, a painful Achilles tendonitis or a partial rupture of the calf muscle (gastrocnemius) as it inserts into the Achilles can also cause pain in this area.
Figure 2: Mechanism of Injury – Sudden Change of Direction
Figure 3: Achilles Maximum Load during walking – Heel Rise
Physical Examination
The diagnosis of an Achilles tendon rupture is made entirely on physical examination. Often, there is a substantial defect in the Achilles from 2-5 cm before it inserts into the heel bone. However, the main test is to determine whether the Achilles has been ruptured is the Thompson test. This essentially involves placing the patient on their stomach and squeezing the calf muscle. If the Achilles is intact, the foot will rise [plantar flex]. If it is ruptured, the foot will not move and will tend to be in a lower lying position.
Patients will usually be able to move the foot up and down because there is no injury to the other surrounding muscles and tendons. Sensation and circulation to the foot and ankle will be normal. In addition, x-rays will be normal unless the Achilles injury involves pulling off (avulsion) of the bone on the calcaneus (heel bone). This is quite rare, occurring in only a small fraction of patients with Achilles injuries. Patients suffering this type of Achilles avulsion injury tend to be older with weaker bone.
Imaging Studies
Plain x-rays will be negative in patients who have suffered an Achilles tendon rupture. The rupture will be seen on MRI. However, an MRI is not indicated for acute ruptures unless there is some uncertainty about the diagnosis. For chronic problems of the Achilles or ruptures that are old, an MRI may be very helpful.
An ultrasound can also be used to confirm the diagnosis of an Achilles tendon rupture. It also may be used to monitor healing in some patients who are treated non-operatively.
Treatment
Achilles tendon ruptures can be treated non-operatively or operatively. Both of these treatment approaches have advantages and disadvantages. In general, younger patients with no medical problems may tend to do better with operative treatment, whereas patients with significant medical problems or older age may be best served with non-operative treatment. However, the decision of how the Achilles tendon rupture is treated should be based on each individual patient after the advantages and disadvantages of both treatment options are reviewed. It is important to realize that while Achilles tendon ruptures can be treated either non-operatively or operatively, they must be treated. A neglected Achilles tendon rupture (i.e. one where the tendon ends are not kept opposed) will lead to a marked dysfunction of the lower leg in gait, which will eventually lead to a whole host of other problems. Furthermore, late reconstruction of non-treated Achilles tendon rupture is significantly more complex than initial treatment.
Non-Operative Treatment
Non-operative treatment consists of placing the foot in a downward position [equinus] and providing relative immobilization of the foot in this position until the Achilles has healed. This typically involves casting or some type of stable immobilization for 6 weeks with limited or no weight bearing. The patient can then be transitioned to a boot with a heel lift and then gradually increase their activity level within the boot. It is very important that the status of the Achilles is monitored throughout non-operative treatment. This can be done by examination or via ultrasound. If there is evidence of gapping or non-healing, surgery may need to be considered. Formal protocols have been developed to help optimize non-operative treatments and excellent results have been reported with these protocols. The focus of these treatments is to ensure that the Achilles rupture is in continuity and is healing in a satisfactory manner.
The primary advantage of non-operative treatment is that without an incision in this area, there are no problems with wound healing or infection. Wound infection following Achilles tendon surgery can be a devastating complication and therefore, for many patients, non-operative treatment should be contemplated.
The main disadvantage of non-operative treatment is that the recovery is probably slower. On average, the main checkpoints of recovery occur 3-4 weeks quicker with operative treatment than with non-operative treatment. In addition, the re-rupture rate appears to be significantly higher with non-operative treatment. Re-rupture typically occurs 8-18 months after the original injury.
Operative Treatment
Operative treatment of Achilles tendon ruptures involves opening the skin and identifying the torn tendon. This is then sutured together to create a stable construct. This can be performed through a standard Achilles tendon repair technique or through a mini-incision technique (to read about the different types of techniques, look under “Procedure” in Achilles Tendon Repair). By suturing the torn tendon ends together, they maintain continuity and can be mobilized quicker. However, it is critical to understand that the suture strength in no way will allow the patient to return to reasonable normal activity level until adequate healing of the tendon has occurred. However, it does allow a functional rehab to occur, and therefore typically preserves more calf and lower leg strength that would otherwise atrophy with non-operative management.
The potential advantages of an open repair of the Achilles tendon include:
- Faster recovery: This means that patients will lose less strength.
- Early Range of Motion: They are able to move the ankle earlier so it is easier to regain motion.
- Lower Re-rupture Rate: The re-rupture rate is significantly lower in operatively treated patients (2-5%) compared to patients treated non-operatively (8-15%).
The main disadvantage of an open repair of the Achilles tendon rupture is the potential for a wound-healing problem which could lead to a deep infection that is difficult to eradicate, or a painful scar.
Rehabilitation
It is now accepted, based on well-designed research studies, that a protocol of rehabilitation exercises (combined with specific instructions for weight bearing and bracing) leads to optimal recovery whether the injury is treated with surgery or not.
The outline for the exercises, bracing, and weight-bearing is as follows (adapted from Willets et al, Journal of Bone and Joint Surgery (JBJS) 2011):
Week 0-2
The ankle is braced at 20 degrees of plantar flexion (or a 2 cm lift is placed under the heel in a boot-type brace). No weight is placed on the foot. In the case of surgery, a wound check will occur in this interval.
Week 2-4
The ankle remains braced in plantar flexion. Exercises begin, several times per day out of the brace. The exercises consist of gentle up and down motion of the ankle, taking care not to stretch the Achilles tendon past neutral (90 degrees). Also, inversion and eversion of the ankle is performed, again with the ankle in slight plantarflexion.
Week 4-6
Increased weight-bearing is permitted. The exercises continue as above, and the brace is still worn day and night.
Week 6-8
The heel lift is removed and brace wear continues. Exercises progress, with slow stretching of the tendon past 90 degrees. Some strengthening of the calf occurs with the addition of resistance exercises.
Week 8-12
The brace is gradually weaned, using crutches as needed. Range of motion, strength, and proprioception are gradually optimized.
Week 12+
Regular footwear is optimized, sports-specific training is optimized.
