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 high-performance 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.5

 

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.18

 

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.22 The mesotenal vessels decrease in number 2 to 6 cm proximal to the osseous insertion.24

 

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.21 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.21

 

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.24

 

Spontaneous rupture of the Achilles tendon has been associated with corticosteroid use,12 inflammatory or autoimmune conditions,7,16 collagen abnormalities,6 infectious diseases,2 neurologic conditions,16 and fluoroquinolone use.20

NATURAL HISTORY

 

Chronic Achilles tendon injuries typically result in the patient's inability to complete everyday tasks such as climbing stairs.9

PATIENT HISTORY AND PHYSICAL FINDINGS

 

 

The patient reports sudden pain in the affected leg. Some patients recall an audible pop or snap.

 

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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 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.

 

Magnetic resonance imaging (MRI) (FIG 2) (rarely required in evaluation of Achilles tendon ruptures)

 

 

T1- and T2-weighted images in the axial and sagittal planes should be used to evaluate Achilles tendon ruptures.

 

 

T1 weighted: A complete rupture of the Achilles tendon is identified as a disruption of the signal within the tendon.

 

 

 

 

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.

 

 

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.11

 

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 repair15

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.10

 

 

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%.13

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 Improved cost-effectiveness over open repair3

 

Disadvantages include the following:

 

 

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

 

The repair is performed under local anesthesia (FIG 3).

 

 

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FIG 3 • Local anesthetic used for the procedure.

 

TECHNIQUES

• Exposure

   

  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 and 5 cm above the rupture, and 2.5 cm below the rupture. A total of eight stab incisions are made (TECH FIG 1).

   

  The subcutaneous tissues at each incision site are spread using a hemostat.

   

   

   

  TECH FIG 1 • Incision locations: at the level of the tear, 2.5 and 5 cm above the tear, and 2.5 cm below the tear.

• Suturing

 

 

A size O monofilament polydioxanone suture with two Keith needles, one on either end, is used. 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 2A).

 

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 2B-E).

 

The previous step is repeated at both 5 and 2.5 cm proximal to the rupture (TECH FIG 2F).

 

The suture, now emerging at the level of the rupture, is then tensioned to ensure that it 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 2G).

 

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.

 

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TECH FIG 2 • A. The needle is passed transversely, and the suture is manipulated until equal lengths are

obtained. B-E. Diagram outlining the technique used for percutaneous repair of an acute Achilles tendon

rupture. F. Crisscross fashion to advance the suture distally through the tendon at 45-degree angles. G.

The suture is advanced distally across the rupture site.

 

 

 

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PEARLS AND PITFALLS

No need for antibiotic prophylaxis Perform technique with two Keith needles.

To avoid sural nerve injury, use the “nick and spread” technique or lengthen the lateral incisions at the level of the rupture and at the musculotendinous junction to 1.0-1.5 cm. Use two small Langenbeck

retractors to further visualize the location of the sural nerve lying superficial to the fascia.17 Intraoperative ultrasound has been described to improve needle placement and tendon edge

approximation during percutaneous repair. In a study by Soubeyrand et al,23 needle placement was corrected 55% of the time due to ultrasound initially showing incorrect needle trajectory around the tendon.

 

 

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-weight bearing of the foot and ankle in an adjustable boot locked in 20 degrees of plantarflexion (FIG 4). 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. 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.

 

Patel et al19 described allowing patients to immediately bear weight on a percutaneous Achilles tendon repair.

 

 

Postoperatively, patients were placed in a plantigrade short-leg cast and allowed immediate weight bearing.

 

At week 2, patients were in a plantigrade walking boot and encouraged to ambulate to tolerance and start Thera-Band exercises.

 

The wedge height decreased over 3 weeks.

 

 

 

FIG 4 • Orthosis used for rehabilitation.

 

 

At week 6, physical therapy started with range of motion and strengthening.

 

The average American Orthopaedic Foot and Ankle Society (AOFAS) scale was 96 (range, 81 to 100) points. Ninety percent of patients were able to return to desired level of activity.

 

 

OUTCOMES

Retrospective review of 10 consecutive patients with acute Achilles tendon ruptures25: No reruptures

No major complications

One sural nerve injury

Mean return to full activity at 6.1 months 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 al14 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 al8 reported mean operative times of 28.5 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 al4 noted significant increased tendon thickness and increased loss of dorsiflexion in the openly treated patients.

 

Out of 133 percutaneously repaired tendons, one patient (0.7%) sustained a complete rerupture and four patients (3%) sustained a partial rupture, compared with three (2.8%) and zero patients, respectively, in the open repair group.

 

Sural nerve injury occurred in six patients (4.5%) in the percutaneous repair group and three patients (2.8%) in the open repair group.

 

Wagnon and Akayi26 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.

 

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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 thrombosis4

 

 

REFERENCES

1. Arner O, Lindholm A. Subcutaneous rupture of the Achilles tendon; a study of 92 cases. Acta Chir Scand Suppl 1959;116(suppl 239):1-51.

    

    

2. Arner O, Lindholm A, Orell S. Histologic changes in subcutaneous rupture of the Achilles tendon; a study of 74 cases. Acta Chir Scand 1959;116:484-490.

    

    

3. Carmont M, Heaver C, Pradhan A, et al. Surgical repair of the ruptured Achilles tendon: the cost-effectiveness of open versus percutaneous repair. Knee Surg Sports Traumatol Arthrosc 2013;21:1361-1368.

    

    

4. Cretnik A, Kosanovic M, Smrkolj V. Percutaneous versus open repair of the ruptured Achilles tendon: a comparative study. Am J Sports Med 2005;33:1369-1379.

    

    

5. Cummins E, Anson B, Carr B, et al. The structure of the calcaneal tendon (of Achilles) in relation to orthopaedic surgery, with additional observations on the plantaris muscle. Surg Gynecol Obstet 1946;83:107-116.

    

    

6. Dent CM, Graham GP. Osteogenesis imperfecta and Achilles tendon rupture. Injury 1991;22:239-240.

    

    

7. Dodds WN, Burry HC. The relationship between Achilles tendon rupture and serum uric acid level. Injury 1984;16:94-95.

    

    

8. Haji A, Sahai A, Symes A, et al. Percutaneous versus open tendo Achilles repair. Foot Ankle Int 2004;25:215-218.

    

    

9. Hattrup SJ, Johnson KA. A review of ruptures of the Achilles tendon. Foot Ankle 1985;6:34-38.

    

    

10. Inglis AE, Scott WN, Sculco TP, et al. Ruptures of the tendo achillis. An objective assessment of surgical and non-surgical treatment. J Bone Joint Surg Am 1976;58:990-993.

     

     

11. Kabbani YM, Mayer DP. Magnetic resonance imaging of tendon pathology about the foot and ankle. Part

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12. Kennedy JC, Willis RB. The effects of local steroid injections on tendons: a biomechanical and microscopic correlative study. Am J Sports Med 1976;4:11-21.

     

     

13. Kocher MS, Bishop J, Marshall R, et al. Operative versus nonoperative management of acute Achilles tendon rupture: expected-value decision analysis. Am J Sports Med 2002;30:783-790.

     

     

14. Lim J, Dalal R, Waseem M. Percutaneous vs. open repair of the ruptured Achilles tendon—a prospective randomized controlled study. Foot Ankle Int 2001;22:559-568.

     

     

15. Maffulli N. Rupture of the Achilles tendon. J Bone Joint Surg Am 1999;81:1019-1036.

     

     

16. Maffulli N, Irwin AS, Kenward MG, et al. Achilles tendon rupture and sciatica: a possible correlation. Br J Sports Med 1998;32:174-177.

     

     

17. Majewski M, Rohrbach M, Czaja S, et al. Avoiding sural nerve injuries during percutaneous Achilles tendon repair. Am J Sports Med 2006;34:793-798.

     

     

18. O'Brien M. Functional anatomy and physiology of tendons. Clin Sports Med 1992;11:505-520.

     

     

19. Patel VC, Lozano-Calderon S, McWilliam J. Immediate weight bearing after modified percutaneous Achilles tendon repair. Foot Ankle Int 2012;33:1093-1097.

     

     

20. Royer RJ, Pierfitte C, Netter P. Features of tendon disorders with fluoroquinolones. Therapie 1994;49:75-76.

     

     

21. Saltzman CL, Tearse DS. Achilles tendon injuries. J Am Acad Orthop Surg 1998;6:316-325.

     

     

22. Schmidt-Rohlfing B, Graf J, Schneider U, et al. The blood supply of the Achilles tendon. Int Orthop 1992;16:29-31.

     

     

23. Soubeyrand M, Serra-Tosio G, Campagna R, et al. Intraoperative ultrasonography during percutaneous Achilles tendon repair. Foot Ankle Int 2010;31:1069-1074.

     

     

24. Strocchi R, De Pasquale V, Guizzardi S, et al. Human Achilles tendon: morphological and morphometric variations as a function of age. Foot Ankle 1991;12:100-104.

     

     

25. Tomak SL, Fleming LL. Achilles tendon rupture: an alternative treatment. Am J Orthop 2004;33:9-12.

     

     

26. Wagnon R, Akayi M. The Webb-Bannister percutaneous technique for acute Achilles' tendon ruptures: a functional and MRI assessment. J Foot Ankle Surg 2005;44:437-444.