Current And Emerging Conservative Modalities For Achilles Tendonitis
A delayed diagnosis of Achilles tendonitis can lead to recalcitrant cases of posterior heel and leg pain. With this in mind, this author discusses common etiologies of this condition and reviews the evidence on a range of conservative therapies.
The Achilles tendon is the largest tendon in the body and is one of the strongest tendons in the body. During the gait cycle, the Achilles tendon can receive a load stress that is 3.9 times body weight during walking and 7.7 times body weight when running.1 The Achilles tendon arises from the aponeuroses of the gastrocnemius muscle and the soleus muscle as their slips course distally along the posterior aspect of the leg. Approximately 15 cm in length, the Achilles tendon forms by bundles of collagen fibers that rotate anterior to medial to posterior to lateral as the tendon courses proximally to its insertion along the posterior and inferior aspect of the calcaneus.2,3
Although the Achilles tendon can withstand great stresses from physical activities such as from running and jumping, it is also prone to injury, particularly in the context of biomechanical abnormalities within the gait cycle that further promote the development of Achilles tendon injuries.4,5
Delays in diagnosis and treatment can often lead to the development of recalcitrant cases of posterior heel and leg pain. These delays can make the conservative management of these injuries a challenge for clinicians. Despite these challenges, there are a variety of current and emerging conservative care modalities available in the clinical armamentarium for the management of this challenging clinical presentation.
Tendonitis Versus Tendinosis
When discussing Achilles tendinopathy, it is important to establish a consistent nomenclature to adequately describe these complex injury presentations. Tendon injuries can be largely grouped into several broad categories: traumatic rupture, tendonitis and tendinosis (which can ultimately lead to atraumatic rupture).6,7
Simply defined, tendonitis is inflammation of a tendon secondary to an acute injury.8,9 Inflammation is the body’s natural response to injury or disease, and this inflammation often causes swelling, pain or irritation. Achilles tendonitis can be further subdivided into various types based upon the anatomic locations involved. The two most commonly described presentations of Achilles tendonitis are insertional and non-insertional tendonitis.7
Insertional Achilles tendonitis involves inflammation at the broad insertion of the Achilles tendon along the posterior aspect of the calcaneus. This type of Achilles tendonitis can occur even with minimal levels of physical activity. Non-insertional Achilles tendonitis commonly presents with inflammation of the Achilles tendon fibers along the more central portions of the Achilles tendon. These types of injuries are common in younger, more active patients. Often, clinicians will find these injuries in the “watershed region,” an area of relative avascularity along the distal course of the Achilles tendon, approximately 2 to 6 cm from its insertion along the posterior aspect of the calcaneus.10,11
Both insertional and non-insertional Achilles tendinopathy can, if left untreated, lead to tendon degeneration and scar tissue formation. In some instances, these areas of degeneration can ossify, creating retrocalcaneal osteophytes (in the context of insertional Achilles tendonitis) and intra-substance tendon calcifications in those patients suffering from non-insertional Achilles tendonitis.7,12,13