Achilles Tendon Rupture

Background

Ruptures of the Achilles tendon most commonly occur spontaneously in healthy, young, active individuals who are aged 30-50 years and have no antecedent history of calf or heel pain. Unlike tears or ruptures at the musculotendinous junction of the Achilles tendon (tennis leg), Achilles tendon ruptures are located within the tendon substance itself, approximately 1-2 inches proximal to its insertion into the calcaneus. Poor conditioning, advanced age, and overexertion are risk factors for this injury. However, the common precipitating event is a sudden eccentric force applied to a dorsiflexed foot. Ruptures of the Achilles tendon also may occur as the result of direct trauma or as the end result following Achilles peritenonitis with or without tendinosis.

Achilles tendon pathology, other than rupture, can be classified into a spectrum of injuries including peritenonitis, tendinosis, and peritenonitis with tendinosis. Patients with peritenonitis experience localized burning pain along the tendon during or following activities; as the disease progresses, onset of pain may occur earlier during activities, with decreased activity level, or even at rest. Tendinosis usually is comprised of an asymptomatic, noninflammatory, degenerative disease process (mucoid degeneration); patients with tendinosis may complain of a sensation of fullness or a nodule in the back of the leg. Peritenonitis with tendinosis is comprised of activity-related pain, diffuse swelling of the tendon sheath, and presence of nodules. Treatment of these entities is not discussed in this article.

Frequency

United States

The true prevalence of Achilles tendon rupture is unknown, although it occurs more commonly in men who are in their third to fifth decade of life and who participate in recreational activities.

Functional Anatomy

The Achilles tendon, coined after the mythologic Greek god, is the largest and strongest tendon in the human body. The Achilles tendon is formed from the tendinous contributions of the gastrocnemius and soleus muscles coalescing approximately 15 cm proximal to its insertion. Along its course in the posterior aspect of the leg, the tendon spirals 30-150° until it inserts into the calcaneal tuberosity. The gliding ability of the Achilles tendon is aided by a thin sheath of paratenon rather than a true synovial sheath. The sheath of paratenon is composed of a visceral layer and a parietal layer.

The blood supply of the Achilles tendon arises from its osseous insertion, its musculotendinous junction, and multiple infiltrating mesosternal vessels, which cross the layers of the anterior paratenon. Various injection and nuclear medicine studies have demonstrated a paucity of mesosternal and intratendinous vessels 2-6 cm proximal to the heel insertion (ie, the watershed area). Due to the relative lack of blood supply in this area, the tendon is less resilient to repetitive microtrauma and has a higher tendency for irritation, degeneration, and rupture.

Sport Specific Biomechanics

The entire gastrocnemius-soleus musculotendinous unit spans the knee, tibiotalar (ankle), and talocalcaneal (subtalar) joints. Contracture of this complex flexes the knee, plantar flexes the ankle, and supinates the subtalar joint. The function of the gastrocnemius-soleus musculotendinous unit is necessary in running, jumping, toe standing, and stair-climbing activities because it forcefully plantar flexes the ankle. During running, forces 10 times the body weight have been measured within the tendon substance.

Treatment

Acute Phase

Rehabilitation Program

Physical Therapy

An individual who ruptures his or her Achilles tendon should seek prompt medical treatment. Physical therapy generally is not indicated in the acute phase of treatment, but it later becomes a crucial part of rehabilitation once adequate healing of the tendon has occurred. The course of treatment (nonoperative vs operative) is determined on a patient-by-patient basis. Typically, both nonoperative and operative treatment options are offered to patients, with particular emphasis on the benefits and risks of each procedure. The recommendations provided in this section regarding operative versus nonoperative treatment are guidelines only and must be personalized to each patient’s needs and condition.

Surgical Intervention

The goal of the orthopedic surgeon is to restore tendon continuity and length to allow the patient to regain his or her functional and desired activity level.

• In general, the author recommends operative intervention for younger, healthier, more active individuals who desire a reliable treatment method. Individuals participating in high school, college, semiprofessional, or professional sports are strongly encouraged to have surgery to decrease the chance of rerupture.
  

• Acute ruptures, large partial ruptures, and reruptures are indications for surgical repair. On the other hand, patients who are more elderly and/or more inactive and those who have systemic illnesses or poor skin integrity are not optimal candidates for operative treatment and are better served with nonoperative treatment.
  

• Numerous operative procedures are available to repair the Achilles tendon. Open and closed (percutaneous) procedures are described. These procedures usually involve primary end-to-end tendon repair with or without fascial or tendon reinforcement.
• Open repair
• In an open repair of the Achilles tendon, both medial and lateral longitudinal approaches have been advocated. Medial incisions allow better visualization of the plantaris tendon and avoid injury to the sural nerve. Midline incisions have been used but have had a higher incidence of wound complications and adhesions.
• A tourniquet is first used to provide hemostasis, and the rupture gap is palpated. The medial or lateral longitudinal incision is made through the skin and subcutaneous fat down to the paratenon. The paratenon is divided along the length of the incision to uncover the ruptured ends, which are then irrigated and debrided. By plantar flexing the ankle, the ends are passively reapposed and are secured with heavy nonabsorbable sutures using a modified Kessler, Krackow, or Bunnell technique.
• Care is taken to not overtighten the repair. Overtightening shortens the tendon length and may lead to loss of dorsiflexion.

• If the repair is insecure, it may be reinforced using a pull-out wire or multiple interrupted sutures and/or it may be augmented with a turn-down fascial graft, a weaved plantaris, or, if necessary, a flexor hallucis longus (FHL) or peroneus brevis (PB) tendon transfer.
• The paratenon and skin are then closed.
• Percutaneous repair

• A percutaneous repair of the Achilles tendon uses multiple percutaneous stab incisions on either side of the ruptured ends. Keith needles and nonabsorbable sutures are passed through these stab incisions and are woven through both the proximal and distal tendon ends. The suture ends are then passed through an enlarged medial incision and are tied as the ankle is held in equinus bringing the ends together.

• Postoperatively, a posterior splint or short-leg cast is placed in gravity equinus for 10-14 days to reduce tension on the incision. With each cast change, the ankle is gradually dorsiflexed, with a neutral position being reached at approximately 4 weeks postsurgery. At that time, the patient is allowed to begin weight bearing on the leg. At 6 weeks postsurgery, the cast is discontinued, and the patient is referred to physical therapy.

• Advantages of operative treatment include a lower rerupture rate (0-5%), a higher percentage of patients to return to sports, and a greater return of strength, endurance, and power.
  

• Disadvantages of operative treatment include hospitalization, high operative costs, wound complications (eg, infection, skin slough, sinus formation), adhesions, and possible sural nerve injury (especially through a lateral longitudinal approach).

Other Treatment

Nonoperative treatment usually is indicated for patients who are elderly and/or inactive and for those with systemic illnesses or poor skin integrity. Patients with diabetes, wound healing problems, vascular disease, neuropathies, or serious systemic comorbidities are encouraged to opt for nonoperative treatment because of significant risks of operative treatment (eg, infection, wound breakdown, repair dehiscence, perioperative complications).

• A short-leg cast is applied to the affected leg while the ankle is placed in slight plantar flexion (gravity equinus). By keeping the foot in this position, the tendon ends are theoretically better apposed. Cast immobilization is continued for about 6-10 weeks. Forced dorsiflexion is contraindicated. The ankle gradually may be dorsiflexed to a more neutral position after a period of immobilization (~4-6 wk). This position is sustained with serial casting or adjustable ankle orthotics. Walking in the cast is allowed at this time. Following cast removal, a 2-cm heel lift in the shoe is worn for an additional 2-4 months. During this time, a rehabilitation program is initiated.

• Advantages of nonoperative treatment include no wound complications (eg, skin breakdown, infection, scar formation, neurovascular injury), decreased hospital costs and physician fees, lower morbidity, and no exposure to anesthesia.
  

• Disadvantages of nonoperative treatment include higher incidence of rerupture (up to 40%) and more difficult surgical repair following rerupture. In addition, the tendon edges may heal in an elongated position because of a gap in the unapposed tendon ends resulting in decreased plantar flexion power and endurance.

Recovery Phase

Rehabilitation Program

Physical Therapy

Following cast removal, gentle passive range of motion (PROM) of the ankle and subtalar joints is initiated. After 2 weeks, progressive resistance exercises (PREs) are added to the regimen. This is followed by aggressive gait training exercises at about 10 weeks following injury (nonoperative patients) or surgery (operative patients), leading toward activity specific maneuvers and a return to activities at 4-6 months. The patient's recovery is largely dependent on the quality of the rehabilitation program, his/her motivation and focus, as well as his/her desired postinjury activity level.

Medication

No medical therapy is indicated for this condition. Medication is only prescribed for symptomatic relief of pain. These medications may include acetaminophen, various nonsteroidal anti-inflammatory drugs (NSAIDs), or narcotics, depending on physician preference.

Drug Category: Nonsteroidal anti-inflammatory agents (NSAIDs)

Although most NSAIDs are used primarily for their anti-inflammatory effects, they are effective analgesics and are useful for the relief of mild to moderate pain.

Drug Name	Ibuprofen (Motrin, Advil, Ibuprin)
Description	DOC for patients with mild to moderate pain. Inhibits inflammatory reactions and pain by decreasing prostaglandin synthesis.
Adult Dose	200-600 mg PO q8h prn
Pediatric Dose	10 mg/kg PO q6-8h prn
Contraindications	Documented hypersensitivity; peptic ulcer disease, recent GI bleeding or perforation, renal insufficiency, or high risk of bleeding
Interactions	Coadministration with aspirin increases risk of inducing serious NSAID-related side effects; probenecid may increase concentrations and, possibly, toxicity of NSAIDs; may decrease effect of hydralazine, captopril, and beta-blockers; may decrease diuretic effects of furosemide and thiazides; may increase PT when taking anticoagulants (instruct patients to watch for signs of bleeding); may increase risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently
Pregnancy	B - Usually safe but benefits must outweigh the risks.
Precautions	Category D in third trimester of pregnancy; caution in congestive heart failure, hypertension, and decreased renal and hepatic function; caution in anticoagulation abnormalities or during anticoagulant therapy

Drug Category: 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 injuries.

Drug Name	Acetaminophen (Tylenol, Feverall)
Description	DOC for pain in patients with documented hypersensitivity to aspirin or NSAIDs, with upper GI disease, or who are taking oral anticoagulants.
Adult Dose	650 mg PO q4h prn
Pediatric Dose	10-15 mg/kg PO q4h prn
Contraindications	Documented hypersensitivity; known G-6-PD deficiency
Interactions	Rifampin can reduce analgesic effects of acetaminophen; coadministration with barbiturates, carbamazepine, hydantoins, and isoniazid may increase hepatotoxicity
Pregnancy	B - Usually safe but benefits must outweigh the risks.
Precautions	Hepatotoxicity possible in those with chronic alcoholism 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

Drug Name	Acetaminophen and codeine (Tylenol #2, Tylenol #3, Tylenol #4)
Description	Indicated for the treatment of mild to moderate pain. The available dosage strengths are as follows: Tylenol #2: 300 mg Tylenol/15 mg codeine Tylenol #3: 300 mg Tylenol/30 mg codeine Tylenol #4: 300 mg Tylenol/60 mg codeine
Adult Dose	1-2 tab of Tylenol #2 or Tylenol #3 PO q4h prn 1 tab of Tylenol #4 PO q4h prn
Pediatric Dose	Tylenol with codeine elixir (120 mg Tylenol + 12 mg codeine)/5 mL Under 3 years: Not established 3-6 years: 5 mL PO tid-qid prn 7-12 years: 10 mL PO tid-qid prn
Contraindications	Documented hypersensitivity
Interactions	Toxicity increases with CNS depressants or tricyclic antidepressants
Pregnancy	D - Unsafe in pregnancy
Precautions	Head injury; increased intracranial pressure; acute abdominal injury; impaired renal, hepatic, thyroid, or adrenocortical function; prostatic hypertrophy or urethral stricture; and asthma (tabs) Caution in patients dependent on opiates since this substitution may result in acute opiate-withdrawal symptoms; caution in severe renal or hepatic dysfunction; may cause dizziness, sedation, nausea, vomiting, constipation, urinary retention, rash, respiratory depression, and/or hepatotoxicity (overdose)