Achilles Tendinitis and Pronation
By John Hyland, DC
Whenever a patient or an athlete reports problems with Achilles tendinitis, a close examination of foot and ankle function must be performed. In addition to treating the inflamed tendon of the gastrocnemius-soleus muscle complex, long-term prevention has to be considered. Recurring injuries to this tendon can significantly affect sports enjoyment and performance levels. A rupture of the tendon will likely require surgery, and occasionally ends participation in competitive and recreational sports completely.
Inflammation of the Achilles Tendon
All forms of tendinitis are due to microtrauma, either from excessive or abnormal activity on a normal tendon, or from normal stresses on an abnormal tendon. Inflammation develops in and around the tendon (peritendinitis). Symptoms are usually described as diffuse pain in or around the back of the ankle (from the calf to the heel).
The pain is aggravated by activity, especially uphill running or climbing stairs. Palpation will find a tender thickening of the peritendon, and there may be crepitus during plantar and dorsiflexion. Patients usually present with the complaint of being unable to participate in sports activities due to pain at their heel and lower calf. Often, a recent increase in activity levels or change in footwear is reported.
Hyperpronation and the Achilles Tendon
The Achilles tendon insertion on the calcaneus is medial to the axis of the subtalar joint, making the calf muscles the most powerful supinators of the subtalar joint.1 Therefore, when excessive pronation occurs, eventually the tendon undergoes overuse degeneration and inflammation. This was well-described by Clement and his fellow investigators at the University of British Columbia in Vancouver, Canada. They describe how “pronation generates an obligatory internal tibial rotation which tends to draw the Achilles tendon medially. Through slow motion, high-speed cinematography we have seen that pronation produces a whipping action or bowstring effect in the Achilles tendon. This whipping action, when exaggerated, may contribute to microtears in the tendon, particularly in its medial aspect, and initiate an inflammatory response.”2 These investigators believe that the control of functional overpronation with corrective orthotic devices is a necessary treatment for most patients with Achilles tendinitis.
Poor blood flow may be a contributing factor to Achilles tendon overuse injuries, and especially with tendon tears. Clement and his fellow authors speculate that “in individuals who overpronate, the conflicting internal and external rotatory forces imparted to the tibia by simultaneous pronation and knee extension may blanch or wring out vessels in the tendon and peritendon causing vascular impairment and subsequent degenerative changes in the Achilles tendon.” This “region of relative avascularity” extends from 2 to 6 cm above the insertion into the calcaneus, and is a common site of rupture of the Achilles tendon. This makes it especially important to ensure good blood flow during the healing of this condition.
- Restricted activity: jumping, running, and other activities which stress the tendon are eliminated, while easy walking is still encouraged. Bicycling is allowed, as long as the pedals are pushed with the heels, and not with the forefeet. Immobilization is not recommended.
- Temporary heel lifts: bilateral higher heels reduce the tensile loading on the tendon, and permit the patient to continue to be ambulatory.
- Cryotherapy: frequent (hourly) ice massage and/or cold packs help reduce inflammation.
- Vitamin C with bioflavonoids: a natural anti-inflammatory that will speed healing.
- Ultrasound: initially pulsed, then constant and direct (once inflammation has subsided).
- Deep friction massage: to stimulate healing deep in the tendon and prevent adhesions.3
- Orthotics for pronation: to reduce the stresses on the tendon due to “whipping action.”
- Shock absorption: viscoelastic inserts will decrease the amount of shock at heel strike.
- Heel cord stretching: “runner’s stretch” against a wall. All exercises should be performed with corrective orthotics in place.4
- Eccentric strengthening: standing on the edge of a stair, do a toe raise up, then rapidly drop the involved heel as far as possible, returning by pushing back up with the uninvolved leg.5
- Wobble board training: to stimulate proprioception and neuromuscular control.6
Achilles tendinitis can be easily treated conservatively. Steroid injections and casting are seldom used these days. One of the most important treatment methods is to reduce any tendency to pronate excessively. In addition to custom-made orthotics, runners should wear well-designed shoes which provide good heel stability with a small amount of additional heel lift. This helps prevent Achilles tendon problems, and is especially important in athletes running for more than a few miles at a time. Once the local inflammation has been controlled, improved blood flow to the region of relative avascularity is necessary.
The use of corrective orthotics can prevent many overuse problems from developing in the lower extremities. Investigation of foot biomechanics is a good idea in all patients, but especially for those who are recreationally active. Competitive athletes must have regular evaluation of the alignment and function of their feet, in order to avoid potentially disabling injuries.
About the Author
Dr. John Hyland has practiced for more than 20 years in Colorado and was the developer and director of four Chiropractic rehabilitation practices for more than eight years. He is a postgraduate faculty member for several Chiropractic colleges. In addition to his specialty board certifications in Chiropractic orthopedics (DABCO) and radiology (DACBR), Dr. Hyland is nationally certified as a strength and conditioning specialist (CSCS) and a health education specialist (CHES). He now consults, advises, and trains doctors of Chiropractic in the concepts and procedures of spinal rehabilitation and wellness exercise.
1 Subotnick SI. Sports medicine of the lower extremity. New York: Churchill Livingstone; 1989:475.
2 Clement DB, et al. Achilles tendinitis and peritendinitis: etiology and treatment. Am J Sports Med 1984; 12:179-84.
3 Lear L. Transverse friction massage. Sports Med Update 1996; 10:18-25.
4 Hertling D, Kessler RM. Management of common musculoskeletal disorders. 2nd ed. Philadelphia: JB Lippincott; 1990:405.
5 Standish WD, et al. Tendinitis: analysis and treatment for running. Clin Sports Med 1985; 4:593-609.
6 Kibler WB, et al. Functional rehabilitation of sports and musculoskeletal injuries. Gaithersburg, MA: Aspen Publishers; 1998:282.