ACHILLES TENDON INJURY

ACHILLES TENDON INJURY

Achilles tendon rupture is a complete disruption of the Achilles tendon, observed most commonly in patients aged 30-50 years, usually occurring at a point 4-5 cm proximal to the calcaneus. This area above the calcaneus is the zone of poor blood flow in the tendon.

Achilles tendonitis is inflammation of the tendon or para tendon, usually resulting from overuse associated with a change in playing surface, footwear, or intensity of an activity.

PATHOPHYSIOLOGY

Areas of degeneration may predispose patients to Achilles tendon ruptures (eg, from chronic tendonitis or Tendinopathy), or prior cortisone injections may lead to tendon rupture.

Common pathophysiology of overuse syndromes applies to Achilles overuse injuries.

FREQUENCY

Exact frequency varies and has been reported at 6 cases per 100,000 persons. The condition commonly occurs in the 30- to 44-year-old recreational athletes, and as many as 72-89% of injuries occur during athletic ventures.

Some reports show Achilles tendon rupture to be the third most common tendon rupture.

MORTALITY/MORBIDITY

Mortality is unreported. Morbidity can include chronic shortening or contracture with Achilles tendon rupture and tendon degeneration with tendonitis.

SEX

Achilles tendon injuries are more prevalent in males at a ratio of 6:1, perhaps due to sports-specific involvement.

AGE

This injury usually is observed in recreational athletes aged 30-50 years. As with gastrocnemius tears and strains, this population often is active only intermittently, and they often still challenge their bodies with high-force activities, predisposing them to these kinds of injuries.

CLINICAL

HISTORY

• Achilles tendon rupture is characterized by an acute onset of pain in the distal rear leg. The patient reports feeling like he or she has been shot, kicked, or cut in the back of the leg, resulting in an inability to ambulate further. A very strong athlete, however, usually is able to overcome that gait abnormality by using other plantar flexors to ambulate normally.

• Some patients have a history of chronic recurrent calf or Achilles tendon area pain or prior cortisone injection.

• Achilles tendonitis is seen in jumpers and correlates with the risk factors of increased intensity, participation in a new activity, or new or unsuitable footwear. Injury is observed more commonly in runners, gymnasts, cyclists, and volleyball players; hyperpronation may contribute. In cyclists, a causative factor may be low saddle height, resulting in extra dorsiflexion of the ankle with pedaling.

PHYSICAL

• Achilles tendon rupture is indicated by obvious leg swelling with a palpable defect in the Achilles tendon. Active plantar flexion is weak or absent. Some strong athletes still may be able to perform toe raises by overcoming the defect with strong peroneals, toe flexors, and posterior tibialis.

• The Thompson test generally is positive. This test is performed by having the patient lie prone with his knee passively flexed. Squeeze the calf, looking for normal foot plantar flexion. Absence of plantar flexion is considered a positive test. Comparison easily can be made to the uninjured side.

• In Achilles tendonitis, the area is tender to palpation from 2-5 cm proximal to the calcaneus. Nodules also may be palpable, as well as a "wet leather" sign of crepitation with ankle plantar flexion and dorsiflexion. This is demonstrated by gently squeezing or palpating the Achilles tendon while the athlete or patient actively plantar flexes and dorsiflexes the foot and ankle. The examiner's fingers feel the crepitus as an area of sponginess, as one would expect with "wet leather." Passive ankle dorsiflexion and active resisted plantar flexion may cause increased pain.

CAUSES

• Achilles tendon rupture usually comes after a forced dorsiflexion during active plantar flexion, as with gastrocnemius tears. This is commonly seen in basketball, diving, tennis, and other sports that require forceful push off from the foot. Other predisposing factors include chronic recurrent Achilles tendonitis and prior history of cortisone injections to the Achilles tendon.

• Achilles tendonitis is seen in jumpers and correlates to risk factors of increased intensity, participation in a new activity, or new or unsuitable footwear. Injury is noted more commonly in runners, gymnasts, cyclists, and volleyball players; hyperpronation may contribute. In cyclists, low saddle height, resulting in extra dorsiflexion of the ankle with pedaling, may be a causative factor.

• Higher-than-average rates of Achilles rupture have been noted in patients with blood type O, gout, systemic lupus erythematosus, and rheumatoid arthritis.

• Achilles tendon rupture is seen in patients who are using steroid medication and fluoroquinolone-type antibiotics.

DIAGNOSIS

LABORATORY STUDIES

• Laboratory studies usually are not necessary in evaluating and diagnosing an Achilles tendon rupture or injury. Evaluation may help rule out some of the other possibilities in the differential diagnosis. These may include CBC count with differential, coagulopathy panel, erythrocyte sedimentation rate, and arthritis panel. Results are all normal in these injuries.

IMAGING STUDIES

• Imaging studies are not necessary to diagnose common Achilles problems; however, they can be helpful in evaluating possibilities in the differential diagnosis and should be ordered as clinically indicated.

• Plain radiography

  • Radiographs of the tibia and fibula often are indicated when the history shows trauma that could have resulted in fracture of these long bones. In Achilles tendonitis, some calcification in the distal Achilles may be evident. With Achilles rupture, the bones appear normal and soft tissue swelling may be evident.

  • Radiographs of the knee and ankle may help discover findings of degenerative or inflammatory arthropathies.

• Ultrasonography of leg and thigh: Ultrasonography of the leg and thigh can help evaluate the possibility of deep vein thrombosis (DVT) and also can be used to rule out a Baker cyst. In experienced hands, ultrasonography also can identify a ruptured Achilles tendon or the signs of Tendinopathy.

• MRI Scan: Magnetic resonance imaging can facilitate definitive diagnosis of a disrupted tendon. This is especially useful when considering the possibility of partial disruption of the Achilles tendon. Partial disruption often is undetectable clinically and may be misdiagnosed as simple Achilles tendonitis; however, partial Achilles disruption often responds to surgical intervention. Imaging the knee can confirm a Baker cyst, as well as the probable underlying pathology causing the Baker cyst.

TREATMENT

PHYSICAL THERAPY

• Achilles tendon rupture

  • Physical therapy for a patient with an Achilles tendon rupture focuses primarily on postoperative care.

  • Therapy usually is initiated at 6-8 weeks following surgery with simple active range of motion (ROM) exercises, 20 minutes twice daily. The patient then progresses to isometric ankle exercises with knee and hip strengthening. Eventually toe raises and progressive resistance exercises are added, culminating with proprioceptive training. At 12 weeks, devices may be utilized to enhance ROM passively with a realistic goal for full range of motion at 6 months.

• Achilles tendonitis

  • Physical therapy for patients with Achilles tendonitis consists of several stages. The initial goal of physical therapy is to control the inflammation.

  • In the first and part of the second phase, pain is used to guide the intensity of exercise. Active ankle dorsiflexion with gentle calf stretching is performed.

  • In the intermediate phase, strengthening replaces active ROM, and neuromuscular control programs are initiated.

  • In the third phase of rehabilitation, progressive stress is applied under good control to allow the collagen to form appropriately. As pain resolves, perform aggressive stretching and active resisted motion.

  • One therapeutic modality that has gained more recent interest is performing eccentric loading exercises. A recent review article demonstrated that this modality improves pain in patients with chronic Achilles Tendinopathy. Further research is ongoing in an effort to clarify the exact role of eccentric training in tendinopathies.

  • Cryotherapy is useful in all of these stages. Physical modalities, such as ultrasound and electrical stimulation, also are useful to decrease pain and inflammation.

MEDICAL ISSUES/COMPLICATIONS

• Medical therapy for a patient with an Achilles tendon rupture consists of rest, pain control, serial casting, and rehabilitation to maximize function. Ongoing debate surrounds the issue of whether medical or surgical therapy is more appropriate for this injury.

  • Activity modification for a ruptured Achilles tendon requires crutch ambulation without weight bearing. Once initiated, serial casting dictates the activity level.

  • Orthotic therapy is useful after serial casting. Serial casting usually results in some Achilles contracture, and heel lifts are used after casting. Depending on the degree of shortening and rate and aggressiveness of physical therapy, initiate use of 1-2 inch heel lifts with gradual weekly or biweekly adjustment directed toward weaning the patient off of the heel lifts.

  • Casting is one way to treat Achilles tendon rupture. Overall healing rates are similar to those of surgical reanastomosis, yet the return-to-activity benefits of surgery are debated. Nonetheless, this is viable therapy, especially for more sedentary patients and older persons. The initial cast applied is a long-leg cast with some knee flexion and ankle plantar flexion to allow free edges of the Achilles to approximate. The cast is changed in series, decreasing the plantar flexion and eventually moving toward short-leg casts in a neutral ankle position. This treatment lasts 6-12 weeks.

  • Recently, high-energy extracorporeal shock wave therapy has shown promise as a treatment for insertional Achilles Tendinopathy. A recent study demonstrated that a single treatment was more effective than traditional conservative treatment in improving pain and enabling patients to return to their activities.

  • Medical therapy for Achilles tendon rupture is concerned primarily with pain control; some of the remedies are outlined below.

SURGICAL INTERVENTION

• Surgical techniques are varied and usually involve reapproximation of the torn ends of the Achilles tendon, sometimes reinforced by the gastrocnemius-soleus aponeurosis or plantaris tendon. Controversy exists as to whether surgical or conservative treatment is preferable.

• Advocates of conservative treatment cite the similar results between conservative and surgical treatment when looking at ROM, strength, power, and functional levels as a reason for avoiding surgery. Surgical advocates argue that full function is achieved more quickly with surgical therapy than with conservative therapy, especially for athletic individuals. The surgical approach is supported by a lower rate of rerupture, greater postoperative power, and low infection rate. Finally, conservative clinicians state that, with early application and prolonged duration of casting, the rerupture rate is decreased significantly.

• Surgery has often been applied in cases of recalcitrant Achilles tendonitis. Techniques include peritenon stripping and debridement of pathologic tissue to create an acute and better healing wound. Aftercare involves prolonged casting, and there is concern that the immobilization caused by casting is as curative as the surgical technique. Nonetheless, surgery is usually a last resort in treatment of tendonitis.

• While the reasons are not precisely known, surgery tends not to be as successful in nonathletic individuals with chronic Achilles Tendinopathy. Nonathletic patients tend to have a more prolonged recovery, a greater risk of complications, and they are more likely to need further surgery than athletic individuals.

MEDICATION

Two major categories of drugs used in Achilles tendon rupture and Achilles tendonitis are analgesics, both opioid and non-opioid, and nonsteroidal anti-inflammatory agents (NSAIDs).

ANALGESICS

Pain control is essential to quality patient care. Analgesics ensure patient comfort and have sedating properties, which are beneficial for patients who have sustained trauma or have sustained injuries.

ACETAMINOPHEN (Tylenol, Aspirin Free Anacin)

DOC for pain in patients with documented hypersensitivity to aspirin or NSAIDs, with upper GI disease, or who are taking oral anticoagulants.

Adult: 500-1300 mg PO q6h prn.

Pregnancy

B - Usually safe but benefits must outweigh the risks.

Precautions

Hepatotoxicity possible in chronic alcoholics following various dose levels; severe or recurrent pain or high or continued fever may indicate a serious illness; APAP is contained in many OTC products and combined use with these products may result in cumulative APAP doses exceeding recommended maximum dose

OPIOID ANALGESICS

Control of moderate to severe pain.

HYDROCODONE (Vicodin, Lorcet, Lortab)

Drug combination indicated for moderate to severe pain.

Adult: 1-2 tabs PO q6h prn

Pregnancy

C - Safety for use during pregnancy has not been established.

Precautions

Tablets contain metabisulfite which may cause hypersensitivity; caution in patients dependent on opiates since this substitution may result in acute opiate-withdrawal symptoms; caution in severe renal or hepatic dysfunction

NONSTEROIDAL ANTI-INFLAMMATORY DRUGS

Have analgesic, anti-inflammatory, and antipyretic activities. Their mechanism of action is not known, but they may inhibit cyclo-oxygenase activity and prostaglandin synthesis.

Other mechanisms may exist as well, such as inhibition of leukotriene synthesis, lysosomal enzyme release, lipoxygenase activity, neutrophil aggregation, and various cell membrane functions.

NAPROXEN (Naprosyn, Aleve, Naprelan, Anaprox)

For relief of mild to moderate pain; inhibits inflammatory reactions and pain by decreasing activity of cyclo-oxygenase, which results in a decrease of prostaglandin synthesis.

Adult: 500 mg PO bid prn

Pregnancy

B - Usually safe but benefits must outweigh the risks.

Precautions

Category D in third trimester of pregnancy; acute renal insufficiency, interstitial nephritis, hyperkalemia, hyponatremia, and renal papillary necrosis may occur; patients with preexisting renal disease or compromised renal perfusion risk acute renal failure; leukopenia occurs rarely, is transient, and usually returns to normal during therapy; persistent leukopenia, granulocytopenia, or thrombocytopenia warrants further evaluation and may require discontinuation of drug

CYCLO-OXYGENASE II INHIBITORS

Control of pain and inflammation, especially in cases of contraindication to conventional anti-inflammatories.

Although increased cost can be a negative factor, the incidence of costly and potentially fatal GI bleeds is clearly less with COX-II inhibitors than with traditional NSAIDs. Ongoing analysis of cost avoidance of GI bleeds will further define the populations that will find COX-II inhibitors the most beneficial.

CELECOXIB (Celebrex)

Inhibits primarily COX-2. COX-2 is considered an inducible isoenzyme, induced during pain and inflammatory stimuli. Inhibition of COX-1 may contribute to NSAID GI toxicity.

At therapeutic concentrations, COX-1 isoenzyme is not inhibited thus GI toxicity may be decreased. Seek lowest dose of celecoxib for each patient.

Adult: 200-400 mg/d PO or divided bid.