Conquering Achilles Tendonitis In Athletes
In a survey of professional athletic trainers and team physicians, Achilles tendonitis ranked third behind ankle sprains and plantar fasciitis as the primary presenting complaint within the athletic population.1 Additionally, it accounts for up to 18 percent of all running injuries.2 The condition is highly prevalent among runners, but it is also common in any athlete who endures repetitive high impact microtrauma.3 Regardless of the afflicted population, Achilles tendonitis can severely hamper an athlete’s training and has been the impetus for many athletes to end their careers. Several factors can precipitate the development of Achilles tendonitis, which is known by numerous other terms including tendinosis, peritendinitis, tenosynovitis, peritendinopathy and Achilles tendinopathy. Overuse can be a cause, especially among the “weekend warrior” athletes. When it comes to elite athletes, however, biomechanical abnormalities that cause abnormal or prolonged pronation or excessive supination can be an etiological factor. Rheumatic disorders, although they are much less common, can be an underlying etiology. Sudden increases in training, training intensity, changes in training surfaces, changes in shoegear and muscular imbalance can all play a role.3 Ensure A Thorough Anatomical Understanding In order to provide optimal care, it’s essential to have a thorough knowledge of the associated anatomy of the superficial posterior leg and hindfoot. The gastrocnemius originates as medial and lateral muscle bellies from their respective femoral condyles and courses down the upper half of the leg, transitioning to a wide aponeurosis and ultimately uniting with the soleus to form the tendo Achilles. The soleus takes its origins from the posterior tibia, fibula and interosseous membrane, courses down the leg and ultimately shares its final attachment with the gastrocnemius through the tendo Achilles. The tendo Achilles has a broad insertion on the middle one-third of the posterior calcaneus and sends fibers around the undersurface of the calcaneus to unite with the plantar fascia. The tendo Achilles inserts medially to the subtalar joint axis. Between the superior surface of the calcaneus and the Achilles is the retrocalcaneal bursa, which provides protection and cushioning of the tendon from the adjacent bony surface. Unlike the invariably present retrocalcaneal bursa, the pre-Achilles bursa, which lies between the tendon and the skin, has a less frequent presence. The tendo Achilles is not surrounded by a synovial sheath to constantly bathe the tendon in nourishing synovial fluid, but rather a paratenon. This affects the healing process of the tendon. The paratenon consists of the intimately associated epitenon and the overlying peritenon. The gastroc/soleal complex receives its proximal blood supply from muscular arterial branches. Distally, the common tendon receives its vascularity from the vessels in the peri- and endotenon, musculotendinous junction, osseous insertion and the mesotenon. Lagergran and Lindholm have shown that the tendo Achilles, 2 cm to 6 cm proximal to its calcaneal insertion, is relatively avascular. They have called this the “watershed area.”4 Just prior to the insertion of the tendon onto the Achilles, the fibers undergo a 90-degree turn in which the lateral fibers become posteriorly oriented.5 This provides significant torsional stress on the tendon/bone interface and often is the site of pathology. Unfortunately, as mentioned earlier, potential healing in this area is altered by the relative avascularity and a lack of a synovial sheath. Understanding the mechanics of the gastroc/soleal complex is equally important. The gastrocnemius spans three joints: the knee, ankle and subtalar joint. The soleus crosses the ankle and subtalar joints. Collectively, they function as ankle joint plantarflexors and supinators of the subtalar joint, while the gastroc also flexes the thigh relative to the leg. The gastroc/soleal complex is active from the contact phase of gait to early propulsion. The soleus is active before the gastrocnemius and stabilizes the lateral foot onto the ground during stance and helps to decelerate the STJ during pronation. The soleus also decelerates the forward momentum of the tibia at midstance and propulsion. The gastroc simultaneously plantarflexes the ankle, flexes the knee and supinates the STJ at propulsion. The two muscles are antagonistic at propulsion with the soleus slowing tibial momentum and the gastroc creating forward momentum with knee flexion.6 This fact may contribute to Achilles pathology during instances — such as ankle equinus, tight hamstrings, hill running and excessive STJ pronation — in which increased amounts of knee flexion are required.7 As the STJ supinates to provide a rigid propelling lever, increased tension is placed on the lateral insertion. Conversely, as the STJ pronates to provide a mobile adapter, there is increased tension at the medial aspect of the insertion. The Achilles undergoes extreme stress during activity with forces reported between 2000 and 7000 N.8 Get The Lowdown On Noninsertional Achilles Tendonitis Achilles tendonitis/tendonosis can be classified into two main categories: insertional and noninsertional. Noninsertional Achilles tendonitis occurs proximal to its insertion on the calcaneus in or about the tendon proper. Noninsertional tendonitis is best classified by Puddu, et. al., who describes a continuum consisting of three stages.9 The initial stage consists of Achilles peritendinitis, which is inflammation of only the paratenon and surrounding soft tissue structures such as an associated bursa. The second stage is peritendinitis with tendinosis where the chronic inflammation of the paratenon has led to the enzymatic degradation and compromise of the tendon proper. When you examine a tendon at this stage, you’ll see varying amounts of necrosis, longitudinal tears, intratendinous calcification or even rupture. Achilles tendinosis or frank mucoid degeneration of the tendon proper is the final stage in the classification system. More often than not, you’ll make this diagnosis during an intraoperative tendon inspection after an acute rupture has occurred. Your goal is to halt and reverse the progression of tendonitis into tendinosis, and subsequently prevent tendon degeneration and possible rupture. Clinically, patients with noninsertional Achilles pathology typically present with a gradual onset of pain along the tendon at the watershed area. These patients tend to be in their 20s or 30s. Initially, the pain is often worse at morning or after exercise. If this is a long-standing problem, patients may experience constant pain while weightbearing. Often, there is localized tenderness and crepitus in the area. The tendon may feel enlarged upon palpation and is often nodular. You’ll often see localized edema as well. Be aware that ankle joint dorsiflexion may be limited compared to the contralateral limb due to the tight heel cord and may elicit pain. In the competitive athlete, a decline in performance in conjunction with any of the above symptoms is common in Achilles tendonitis. Radiographic views should include lateral, oblique and modified calcaneal axial projections. Take the modified calcaneal axial projection with the head of the projector 10 degrees from vertical, aiming at the posterior calcaneus. These exams may reveal intratendinous calcifications and allow you to appreciate any calcifications in multiple planes. Obtaining an MRI is also helpful to delineate tissue involvement. In both noninsertional and insertional Achilles tendonitis, if you suspect a rheumatologic origin, an appropriate lab workup is in order. Reviewing The Conservative And Surgical Treatment Options Always initiate conservative treatment in acute cases as many patients do respond favorably with rapid results. McGarvey, et. al., reported an 89 percent success rate with conservative treatment.10 The more acute the condition, the more amenable it will be to conservative treatment. Acute treatment centers around reducing inflammation and tension on the tendon. Antiinflammatory measures include non-steroidal antiinflammatories, rest, local ice massage, electrostimulation, ultrasound, iontophoresis and contact baths. Corticosteroid injections are strongly discouraged in this area as they may further weaken a possibly already degenerated tendon. For the serious athlete, a lengthy period of absolute rest may not be possible. In these instances, you should emphasize relative rest with alternative activity. Swimming is an excellent form of alternative activity that does not stress the Achilles tendon. Essentially, the athlete may participate in any activity that does not cause pain to the area. To decrease tension on the Achilles, many practitioners employ a heel lift. This is appropriate in the acute phase but the patient should be phased out of the lift and into a stretching regimen as soon as possible. If overpronation is the underlying etiology, then a functional orthotic may be in order. If symptoms persist despite your conservative therapy efforts, surgical intervention may be necessary. Authors recommend waiting anywhere from three months and one year before considering surgical treatment.1 We feel there is no set time for such treatment and that it is really a matter of clinical judgment. Considerations for competitive athletes are much different than those for recreational athletes. More aggressive treatment may be necessary to allow the athlete to return to activity as soon as possible, as opposed to long spans of conservative care, especially in refractory cases. For the recreational athlete or the non-athlete, it may be prudent for both you and your patient to exhaust conservative measures before considering surgical intervention. These decisions depend on your understanding of the patient’s condition and needs. For Puddu group I, Kvist and Kvist described releasing the crural fascia on both sides of the tendon and trimming the peritendon if it was hypertrophied.11 They reported excellent/good results in 194 of 201 cases. Nelen et. al., reported a similar procedure on 170 cases and found 86 percent excellent/good results.11 For Puddu group II, in addition to resecting the fascia, researchers performed debridement and repair of the tendon itself in 26 cases. In 24 of these cases, they had to employ a turn down flap due to the extensive debridement. Using a similar procedure, Nelen, et. al., reported 73 percent excellent/good results. Other studies by Schepsis and Leach, Clancy, et. al, Gould and Korsen, and Snook demonstrated similar results.11 Although usually not necessary, radical debridement of a severely degenerated tendon may require subsequent augmentation or perhaps a tendon transfer of the FHL, FDL or peroneus brevis. Incisional approaches can vary but should be adequate for full access to the pathology. If you find it necessary to employ a medial tendon approach, keep in mind that it does permit easy access to the plantaris tendon and FHL tendon while avoiding involvement of the sural nerve. How To Identify Insertional Achilles Tendonitis Insertional Achilles tendonitis is a separate condition occurring at the tendon/bone interface. It occurs more frequently among older athletes in their 50s and 60s, and these patients tend to be overweight.12 Often, but not always, you’ll find this condition is associated with a retrocalcaneal bursitis, superficial bursitis and a Haglund’s deformity. The bony prominence predisposes the anterior aspect of tendon to irritation and is even more likely to occur in the cavus foot. It is thought that the combination of chronic overuse with the retrocalcaneal bursitis and bony impingement creates a chronic inflammatory response with chemical degradation and mechanical abrasion of the Achilles with subsequent calcification in the tendon proper.11 Clinically, these patients experience a gradual onset of pain at the bone/tendon interface, which is often aggravated by exercise initially and becomes more constant later. Typically, you can pinpoint the pain to the posterolateral aspect of the interface. The enlargement in the posterior aspect of the calcaneus can be due to both edema and thickening of the Achilles tendon. Keep in mind that the affected side will often have an associated equinus deformity. There may also be crepitus in the area with ankle joint range of motion. The patient may complain of posterior heel pain when running uphill and note the pain gradually reduces after stretching. Obtain similar radiographs as described above (for the noninsertional cases). When it comes to the radiographic views, you’ll frequently see a Haglund’s deformity in insertional cases. In chronic cases, the bone/tendon interface becomes calcified and you can see a traction exostosis within the tendon. Treating Insertional Tendonitis Conservative treatment of insertional Achilles tendonitis is similar to that of noninsertional tendinitis. You would pursue antiinflammatory measures such as NSAIDs, ice massage, electrostimulation, iontophoresis and contact bathing. Using a soft Tuli-type of heel cup can lessen the friction and irritation at the level of the shoe/tendon insertion interface. In acutely inflamed cases, immobilization may be in order. Once the inflammation has subsided, you should emphasize rehabilitation including an Achilles stretching program. Simple shoe padding may be sufficient in cases of isolated insertional tendonitis. Orthotic therapy consisting of a simple heel lift or even functional orthosis can be helpful. If the patient has localized pain either medially or laterally, it would be appropriate to use a respective heel-to-toe wedge on the orthotic. Athletes who overpronate often find their pain localized medially while supinators localize laterally. Once you have exhausted conservative treatment options, consider surgical treatment. Incisional approaches vary and include a single lateral incision, a combined lateral incision with a secondary incision just medial to the tendon, and a central tendon splitting incision. Your choice of incision is based on site of the pathology as well your preference. Regardless of the approach you use, the goal is to debride all degenerated tendon and remove any calcifications. If you see a traction exostosis, free it from the tendon and resect it. If you notice a Haglund’s deformity, you should address it with either resection or a Keck and Kelly type osteotomy, if indicated. If you see an enlarged and inflamed retrocalcaneal bursa, you should excise it. You can reattach the Achilles tendon to the calcaneus with a tendon anchoring system of your preference. In cases of failed surgery or those with severe tendon derangement, you may need to perform a graft or tendon transfer. Typically, postoperative care consists of six to 10 weeks of immobilization with subsequent transition to full weightbearing complemented by aggressive rehabilitation. It may take up to six months for the athlete to return to full activity. Quick Tips About Rehabilitation Multifaceted rehabilitation is a must with these injuries. Researchers have shown that static stretching techniques can significantly change the fascial architecture of the muscles and reduce overall tension.3 Patients should also initiate muscle strengthening, beginning first with isometrics as they have the least amount of stress on the muscle tendon unit. Let patients know they can also do isotonic and isokinetic exercises at the appropriate time during the postoperative course, but studies have shown eccentric exercises are the most important type of exercise for functional tendon rehabilitation.3 Plyometric training (explosive power training) is being used more frequently in the rehabilitation of competitive athletes. In rehabilitation, it is also necessary to provide proprioceptive training to help coordinate neuromuscular activity. The importance of rehabilitation in these types of injuries cannot be understated. It would be prudent to consider physical therapy consultation and evaluation in treating these patients. Final Thoughts Defining the correct classification of Achilles tendonitis is essential to treatment. Multifaceted conservative treatment is usually effective for both conditions, but some patients will require surgical intervention. In particular, athletes with Achilles tendonitis require a comprehensive, team approach (including physical therapy consults) in order to return to his or her pre-injury state. A thorough knowledge of your patient, the disease process and a systematic treatment approach will provide the highest likelihood of accomplishing this goal. Dr. DeHeer is a Fellow of the American College of Foot and Ankle Surgeons and is a Diplomate of the American Board of Podiatric Surgery. He is also the team podiatrist for the Indiana Pacers and the Indiana Fever. Dr. Offutt is a first-year resident at Winona Memorial Hospital in Indianapolis, IN.
References 1. Moseley JB, Chimenti BT. Foot and Ankle Injuries in the Professional Athlete, ch. 22. In The Foot and Ankle in Sports, first ed., pp 321-328, Mosby, St. Louis, 1995. 2. DeMaio M, Paine R, Drez D. Achilles tendinitis. Sports Med Rehab Series 18:195-204, 1995. 3. Humble RN, Nugent LL. Achilles tendonitis. Clin in Pod Med Surg 18:233-254, 2001. 4. Lagergran C, Lindholm A. Vascular distribution in the Achilles tendon: an angiographic and microangiographic study. Acta Chir Scand 116:491-495, 1959. 5. Cummins EJ, Anson BJ, Carr BW, et. al. The structure of the calcaneal tendon in relation to orthopaedic surgery: with additional observations of the plantaris muscle. Surg Gynecol Obstet 83:107-116, 1946. 6. Root ML, Orien WP, Weed JM. Normal and Abnormal Function of the Foot. Los Angeles, Calif., Clinical Biomechanics Corp., 1977. 7. Lemm M, Blake RL, Colson JP, Ferguson H. Achilles Peritendinitis. JAPMA 82:482-490, 1992. 8. Clain MR, Baxter, DE. Achilles Tendinitis. Foot and Ankle 13:482-487, 1992. 9. Puddu G, Ippolito E, Postacchini F. A classification of Achilles tendon disease. Am J Sports Med 4:540-553, 1970. 10. McGarvey WC, Palumbo RC, Baxter DE, Liebman BD. Insertional Achilles tendinitis: surgical treatment through a central tendon splitting approach. Foot Ankle Int 23:19-25, 2002. 11. Clain MR. Foot and Ankle Injuries in the Professional Athlete, ch. 6. In The Foot and Ankle in Sports, first ed., pp 71-80, Mosby, St. Louis, 1995. 12. Myerson MS, McGarvey W. Disorders of the Achilles tendon insertion and Achilles tendinitis. AAOS Inst Course Lect 48:211-218, 1999.