Karen M. Sutton, Sandra L. Tomak, and Lamar L. Fleming
DEFINITION
Achilles tendon ruptures typically occur about 2 to 6 cm proximal to the tendon's insertion site on the calcaneus.
This injury is relatively common among both highperformance athletes and the recreational athlete, particularly the “weekend warrior.”
Ruptures occur most often in men between 30 and 50 years of age.
ANATOMY
Tendinous portions of the gastrocnemius and soleus muscles coalesce to form the Achilles tendon (FIG 1).
The plantaris muscle is a distinct entity medial to the Achilles tendon.
The soleus tendon originates as a band proximally on the posterior surface of its muscle, and the gastrocnemius tendon emerges from the distal margin of the muscle bellies.
The length of the tendon formed from the gastrocnemius and soleus range from 11 to 26 cm and 3 to 11 cm, respectively.
FIG 1 • Merging of the gastrocnemius and soleus muscles to form the Achilles tendon.
Viewed from proximal to distal, the Achilles tendon progressively becomes thinner in its anteroposterior dimensions, particularly from 4 cm proximal to the calcaneus to its insertion on the calcaneus.4
Ninety-five percent of the tendon collagen is type I collagen; a small percentage is elastic. Seventy percent of the dry weight of the tendon is collagen.17
The blood supply to the Achilles tendon arises from the musculotendinous junction, the osseous insertion, and multiple mesotenal vessels.
The tendon is most poorly vascularized at its midportion, receiving its blood supply from the paratenon.20 The mesotenal vessels decrease in number 2 to 6 cm proximal to the osseous insertion.21
The Achilles tendon receives much of its nutrition from the tenosynovial fluid that bathes the tendon and is contained within the paratenon.
PATHOGENESIS
Ruptures occur most commonly during athletic activities.
Both hyperpronation and cavus foot alignment are associated with Achilles tendon injuries. The cavus foot is thought to place more stress on the lateral side of the Achilles tendon and to absorb shock poorly.19
Inconsistent training, including sudden increases in training intensity; excessive training; training on hard surfaces; and running on sloping, hard, or slippery roads have been implicated in Achilles tendon problems.19
Mechanisms of injury, leading to eccentric loads on the Achilles tendon, include pushing off with the weight-bearing forefoot while extending the knee, unexpected dorsiflexion of the ankle, or violent dorsiflexion of a plantarflexed foot.1
With normal aging, the Achilles tendon decreases in cell density, collagen fibril diameter and density, and fiber waviness. These changes may make the aging athlete more susceptible to injury.21
Spontaneous rupture of the Achilles tendon has been associated with corticosteroid use,11 inflammatory or autoimmune conditions,6,15 collagen abnormalities,5 infectious diseases,2 neurologic conditions,15and fluoroquinolone use.18
NATURAL HISTORY
Chronic Achilles tendon injuries typically result in the patients's inability to complete everyday tasks such as climbing stairs.8
PATIENT HISTORY AND PHYSICAL FINDINGS
The patient reports sudden pain in the affected leg.
Some patients recall an audible pop or
With Achilles tendon ruptures, patients occasionally experience a sensation as though they were “kicked” or “hit” in the injured calf.
Patients report an inability to bear weight and have weakness of the affected lower extremity.
Physical examination should include the following:
Palpation of gap: Palpate along the posterior aspect of the lower leg, and a gap may be felt along the course of the tendon.
Positive: appreciable gap
Thompson test: With the patient prone, squeeze the proximal portion of the calf.
Positive: no plantarflexion of the ankle
False-positive results may be obtained with an intact plantaris tendon.
Knee flexion test: With the patient prone, have him or her actively flex both knees to 90 degrees.
Positive: asymmetric resting tension of both ankles; the affected foot may even fall into neutral or dorsiflexion.
Needle test: Insert a hypodermic needle into the calf medial to the midline and 10 cm proximal to the insertion of the tendon. The ankle is put through passive range of motion.
Positive: the needle points proximally on dorsiflexion.
This test is usually only performed if there remains a high index of suspicion with the other tests being equivocal.
IMAGING AND OTHER DIAGNOSTIC STUDIES
Plain radiographs (rarely required in evaluation of Achilles tendon ruptures)
In a lateral radiograph, the fat-filled triangular space (ie, Kager's triangle) anterior to the Achilles tendon and between the posterior aspect of the tibia and the superior aspect of the calcaneus loses its regular configuration.
MRI (FIG 2) (rarely required in evaluation of Achilles tendon ruptures)
T1and T2-weighted images in the axial and sagittal planes should be used to evaluate Achilles tendon ruptures.
FIG 2 • T2-weighted MRI scan displaying a complete rupture of the Achilles tendon about 5 cm proximal to the insertion site on the calcaneus.
T1-weighted: a complete rupture of the Achilles tendon is identified as a disruption of the signal within the tendon.
T2-weighted: a complete rupture is demonstrated as a generalized increase in signal intensity, and the edema and hemorrhage at the site of the rupture are seen as an area of high signal intensity.10
Ultrasound (useful because it can be performed in the office setting)
Rupture seen as an acoustic vacuum with thick irregular edges
May also be used for postoperative evaluation to assess the structure of the tendon and integrity of repair14
DIFFERENTIAL DIAGNOSIS
Typically, rupture of the Achilles tendon does not conjure up a differential diagnosis.
Because four other muscles plantarflex the ankle, Achilles tendon ruptures may be initially mistaken for ankle sprains; although increasingly less common, it has been reported that up to 20% of Achilles tendon ruptures may be missed by the first doctor to examine the patient.9
NONOPERATIVE MANAGEMENT
Equinus short-leg cast or plantarflexed cam boot for 6 to 8 weeks
At 6 to 8 weeks, start gentle range-of-motion exercises.
A heel lift is used in the transition to wearing normal shoes.
The patient may return to running in 4 to 6 months.
Considered for elderly or sedentary patients, poor surgical candidates (vascular compromise and/or poor skin quality), or patients favoring nonoperative treatment
The rerupture rate after nonoperative management is about 12.1%, compared with the rerupture rate for surgical repair, which is only 2.2%.12
SURGICAL MANAGEMENT
In our hands, percutaneous repair is reserved for acute tears, a minimal tendon gap, and compliant patients.
Advantages of percutaneous repair are as follows:
Low risk of wound complications
Preservation of blood supply for tendon healing
Performed as outpatient procedure
Requires only local anesthetic
Maintenance of tendon length
Earlier return to function when compared to closed treatment
Disadvantages include:
Potential sural nerve injury
Higher rerupture rate versus open repair
Limited patient population
Need for compliance postoperatively
Percutaneous repair is contraindicated in chronic tears, tendon gap, noncompliant patients, and high-level athletes (relative).
Positioning
Prone position
No tourniquet
Injured foot in about 25 degrees of plantarflexion
Approach
Percutaneous
TECHNIQUES
PERCUTANEOUS ACHILLES TENDON REPAIR
The repair is performed under local anesthesia (TECH FIG 1.)
A size 0 monofilament polydioxanone suture with two Keith needles, one on either end, is used.
Medial and lateral stab incisions are made on either side of the Achilles tendon using a no. 15 blade in the following locations: at the level of the rupture; 2.5 cm and 5 cm above the rupture; and 2.5 cm below the rupture. A total of eight stab incisions are made (TECH FIG 2).
The subcutaneous tissues at each incision site are spread using a hemostat.
Beginning at the most proximal lateral wound, the needle is passed transversely, and the suture is then manipulated until equal lengths are established on either side (TECH FIG 3).
The suture is then advanced distally from both sides through the ipsilateral proximal incisions in a crisscross fashion through the tendon at 45-degree angles (TECH FIG 4).
The previous step is repeated at both 5 cm and 2.5 cm proximal to the rupture (TECH FIG 5).
The suture, now emerging at the level of the rupture, is then tensioned to ensure that ist is secured in the proximal Achilles tendon stump.
The suture is then advanced distally across the rupture site, in a fashion similar to the previous step (TECH FIG 6).
The lateral suture is passed through the ipsilateral incision transversely, from lateral to medial, where the ends of the sutures are pulled simultaneously, and then tied; closing the tendon gap.
A hemostat is used to bury the knot and to be sure there is no skin puckering at any of the incision sites.
Staples are placed to approximate the skin.
TECH FIG 1 • Local anesthetic used for the procedure.
TECH FIG 2 • Incision locations: at the level of the tear, 2.5 cm and 5 cm above the tear, and 2.5 cm below the tear.
TECH FIG 3 • The needle is passed transversely, and the suture is manipulated until equal lengths are obtained.
TECH FIG 4 • Diagram outlining the technique used for percutaneous repair of an acute Achilles tendon rupture. D. The finished repair. (Adapted with permission from Tomak SL, Fleming LL. Achilles tendon rupture: An alternative treatment. Am J Orthop 2004;33:9–12.)
TECH FIG 5 • Crisscross fashion to advance the suture distally through the tendon at 45 degree angles.
TECH FIG 6 • Suture is advanced distally across the rupture site.
POSTOPERATIVE CARE
Throughout the rehabilitation period: light active dorsiflexion, muscle strengthening, proprioception exercises, stationary cycling with heel push, soft tissue treatments
For the first 2 weeks: immobilization and non–weightbearing of the foot and ankle in an adjustable boot locked in 20 degrees of plantarflexion (FIG 3). Gentle plantigrade movement of the foot, straight leg raises, and knee range of motion are begun.
Week 2: the boot is adjusted to 10 degrees of plantarflexion.
Week 4: Orthosis is adjusted to neutral; partial weight bearing is initiated.
FIG 3 • Orthosis used for rehabilitation.
Week 6: Full weight bearing is permitted.
Week 8: The foot is placed in a shoe with a heel lift.
Month 3: The patient starts closed-chain exercises, cycling, and elliptical trainer.
Month 6: Running, jumping, and sports activities may be resumed.
OUTCOMES
Retrospective review of 10 consecutive patients with acute Achilles tendon ruptures22:
No reruptures
No major complications
One sural nerve injury
Mean return to full activity at 6.1 months
American Orthopaedic Foot and Ankle Society (AOFAS) ankle hindfoot rating: average score 94
Mean difference of 1.58 cm in calf circumference, with the involved leg having the smaller circumference
Mean plantarflexion peak torque of the uninvolved leg and the involved leg of 67.8 and 52.8 foot-pounds, respectively (at a speed of 30 degrees per second)
Comparative studies of percutaneous versus open Achilles tendon repair
Lim et al13 reported significantly fewer wound complications/infections with percutaneous Achilles repair when compared to open repair. There was no significant difference between the two groups with respect to the duration of the immobilization, return to functional activity, and other complications.
Haji et al7 reported: Mean operative times of 28.5 minutes and 25.9 minutes (statistically significant) and rerupture rates of 2.6% versus 5.7% (not statistically significant), respectively for percutaneous versus open repair.
Cretnik et al3 noted significant increased tendon thickness and increased loss of dorsiflexion in the openly treated patients.
Out of 133 percutaneously repaired tendons, 1 patient (0.7%) sustained a complete rerupture, and 4 patients (3%) sustained a partial rupture, compared with 3 (2.8%) and 0 patients, respectively, in the open repair group.
Sural nerve injury occurred in 6 patients (4.5%) in the percutaneous repair group and 3 patients (2.8%) in the open repair group.
Wagnon and Akayi23 compared the Webb-Bannister percutaneous technique to open repair.
The open repair group had an 8.6% incidence of wound complications (no wound dehiscence occurred in the percutaneous repair group).
Two patients out of 35 experienced rerupture after open repair; 1 patient (out of 22) experienced a rerupture after percutaneous repair.
Patients returned to work a mean of 4 months after open repair and 3.75 months after the Webb-Banister percutaneous repair.
No sural nerve complications occurred.
COMPLICATIONS
Sural nerve injury
Palpable suture knot which may necessitate excision
Rerupture
Deep venous thrombosis3
REFERENCES
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