DEFINITION

Tendinopathy of the Achilles tendon involves clinical conditions in and around the tendon arising from overuse.1

Tendinopathy of the Achilles tendon is common both in athletic and nonathletic individuals. It can affect several regions of the tendon.

One particularly common site is the main body of the tendon, 2 to 4 cm from its insertion on the calcaneus.2

 

 

ANATOMY

 

The two heads of gastrocnemius (medial and lateral) arise from the condyles of the femur, the fleshy part of the muscle extending to about the midcalf. As the muscle fibers descend, they insert into a broad aponeurosis that

contracts and receives the tendon of the soleus on its deep surface to form the Achilles tendon.3

 

The Achilles tendon is the thickest and strongest tendon in the body. About 15 cm long, it originates in the midcalf and extends distally to insert into the posterior surface of the calcaneum. Throughout its length, it receives muscle

fibers from the soleus on its anterior surface.4

 

PATHOGENESIS

 

 

To date, the etiopathogenesis of Achilles tendinopathy remains unclear. Tendinopathy has been attributed to a variety of intrinsic and extrinsic factors.6

 

It has been linked to overuse vascularity, dysfunction of the gastrocnemius-soleus, age, gender, body weight and

height, endocrine or metabolic factors, deformity of the pes cavus, lateral instability of the ankle, the use of quinolone antibiotics, excessive movement of the hindfoot in the frontal plane, marked forefoot varus, changes in training pattern, poor technique, previous injuries, footwear, and environmental factors such as training on hard,

slippery, or slanting surfaces.1,2,3,4,5,6

 

Most of the previously mentioned factors should be considered associative, not causative, evidence, and their role in the cause of the condition is therefore still debatable.8

NATURAL HISTORY

 

Although Achilles tendinopathy has been extensively studied, there is a clear lack of properly conducted scientific research to clarify its cause, pathology, natural history, and optimal management.9

 

The management of Achilles tendinopathy lacks evidencebased support, and tendinopathy sufferers are at risk of long-term morbidity with unpredictable clinical outcome.10

 

Most patients respond to conservative measures, and the symptoms can be controlled, especially if the patients accept that a decreased level of activities may be necessary.10

 

In 24% to 45.5% of patients with Achilles tendinopathy, conservative management is unsuccessful and surgery is recommended after exhausting conservative methods of management, often tried for 3 to 6 months. However, longstanding Achilles tendinopathy is associated with poor postoperative results, with a greater rate of reoperation

before reaching an acceptable outcome.7,11

 

As the biology of tendinopathy is being clarified, more effective management regimens may come to light, improving the success rate of both conservative and operative management.12

PATIENT HISTORY AND PHYSICAL FINDINGS

 

Patients typically present with pain located 2 to 6 cm proximal to the insertion of the tendon and felt after exercise.

 

As the pathologic process progresses, pain may occur during exercise and, when severe, may interfere with activities of daily living.

 

Runners experience pain at the beginning and at the end of a training session, with a period of diminished discomfort in between.

 

The foot and the heel should be inspected for malalignment, deformity, obvious asymmetry in the size of the tendon, localized thickening, a Haglund heel, and any previous scars.11,12,13

 

The tendon should be palpated to detect tenderness, heat, thickening, nodularity, and crepitation.

 

The “painful arc” sign helps to distinguish between lesions of the tendon and paratenon. In paratendinopathy, the area of maximum thickening and tenderness remains fixed in relation to the malleoli from full dorsiflexion to

plantarflexion, whereas lesions within the tendon move with movement of the ankle.14

 

IMAGING AND OTHER DIAGNOSTIC STUDIES

 

Plain soft tissue radiography is useful in diagnosing associated or incidental bony abnormalities.10

 

Ultrasound is the primary imaging method because it correlates well with the histopathologic findings despite being operator-dependent.12

 

Ultrasound promptly identifies hypoechoic areas, which have been shown at surgery to consist of degenerated tissue, and increased thickness of the tendon.

 

Magnetic resonance imaging (MRI) studies should be performed only if the ultrasound scan remains unclear.

 

MRI provides extensive information on the internal morphology of the tendon and the surrounding structures and is useful

 

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in evaluating the various stages of chronic degeneration and in differentiating between peritendinitis and

tendinosis. Areas of mucoid degeneration are shown on MRI as a zone of high signal intensity on T1- and T2-weighted images.13

 

DIFFERENTIAL DIAGNOSIS

Paratendinopathy of the Achilles tendon Acute or chronic rupture of the Achilles tendon Rerupture of the Achilles tendon

Tear of the musculotendinous junction of the gastrocnemiussoleus and the Achilles tendon12

 

NONOPERATIVE MANAGEMENT

 

There is weak evidence of a modest benefit of nonsteroidal anti-inflammatory drugs (NSAIDs) for the alleviation of acute symptoms.5

 

Low-dose heparin, heel pads, topical laser therapy, and peritendinous steroid injection produced no difference in outcome when compared with no treatment.9

 

Medications shown to be effective in randomized controlled trials include peritendinous injection of aprotinin, topical application of glyceryl trinitrate, and the use of ultrasoundguided sclerosing injections in the area of

neovascularization.10

 

 

Painful eccentric calf muscle training can be an effective treatment for noninsertional Achilles tendinopathy.13 Eccentric loading and low-energy shockwave therapy show comparable results.14

SURGICAL MANAGEMENT

 

 

Conservative management is unsuccessful in 24% to 45.5% of patients with tendinopathy of tendo Achilles.14 Surgery is recommended after at least 6 months of conservative management.11

 

The objective is to excise fibrotic adhesions, remove degenerated nodules, and make multiple longitudinal

incisions in the tendon to detect intratendinous lesions and to restore vascularity, possibly stimulating the remaining viable cells to initiate a response in the cell matrix and healing.14

 

 

The defect can be sutured in a side-to-side fashion or left open. Reconstruction procedures may be required if large lesions are excised.

Preoperative Planning

 

Preoperative imaging studies can guide the surgeon in the placement of the incision and in incising the tendon sharply in line with the tendon fiber bundles.

 

Positioning

 

 

Under locoregional anesthesia, the patient is placed prone with the ankles clear of the operating table. The prone position allows excellent access to the affected area.

 

Alternatively, the patient can be positioned supine with a sandbag under the opposite hip and the affected leg positioned in a figure-4 position.

 

A tourniquet is applied to the limb to be operated on. The limb is exsanguinated and the tourniquet is inflated to 250 mm Hg.4

Approach

 

The incision is made on the medial side of the tendon to avoid injury to the sural nerve and short saphenous vein (FIG 1).

 

A straight posterior incision may also be more bothersome with the edge of the heel counterpressing directly on the incision.

 

Maintaining thick skin flaps is vital to reduce the incidence of wound breakdown.7

 

 

 

FIG 1 • Incision used for open surgery. It lies just posterior to the medial border of the Achilles tendon. It avoids the sural nerve and the short saphenous vein, and the scar is away from the shoe counter.

 

TECHNIQUES

• Exposure and Excision of the Paratenon

Expose the paratenon and the Achilles tendon (TECH FIG 1A). Identify and incise the paratenon (TECH FIG 1B).

In patients with evidence of coexisting paratendinopathy, the scarred and thickened tissue is generally excised.

Based on preoperative imaging studies, the tendon is incised sharply in line with the tendon fiber bundles (TECH FIG 1C).

The tendinopathic tissue can be identified, as it generally has lost its shiny appearance and it frequently contains disorganized fiber bundles that have more of a “crabmeat” appearance (TECH FIG 1D).

This tissue is sharply excised (TECH FIG 1E).

 

 

 

 

TECH FIG 1 • A. Paratenon and the Achilles tendon exposed. (continued)

 

 

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TECH FIG 1 • (continued) B. The paratenon is excised. C. Longitudinal tenotomy along the tendon fibers. As the tendon fibers rotate 90 degrees, the longitudinal tenotomy has to follow them. D. The macroscopic appearance of the tendinopathic area is visualized. E. The tendinopathic tissue is excised.

• Gap Repair and Closure

   

  The remaining gap can be repaired using a side-to-side repair, but we leave it unsutured (TECH FIG 2A).

   

  Suture the subcutaneous tissues with absorbable material (TECH FIG 2B).

   

   

   

  TECH FIG 2 • A. Appearance at the end of the procedure. B. The skin wound after suture of the deep tissues. C. Steri-Strips are applied to the surgical wound before a routine compressive bandage. The limb is then immobilized in a below-knee synthetic weight-bearing cast with the foot plantigrade.

   

   

   

   

  The skin edges are juxtaposed with Steri-Strips (TECH FIG 2C) and then a routine compressive bandage. The limb is immobilized in a below-knee synthetic weight-bearing cast with the foot plantigrade.

   

• Tendon Augmentation or Transfer

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  If significant loss of tendon tissue occurs during the débridement, consider a tendon augmentation or transfer. A tendon turndown flap has been described for this purpose.

   

  With a turndown procedure, one or two strips of tendon tissue from the gastrocnemius tendon are dissected out proximally while leaving the strip attached to the main tendon distally.

   

  It is then flipped 180 degrees and sewn in to cover and bridge the weakened defect in the distal tendon.

• Plantaris Weave

   

  A plantaris weave has also been reported for this purpose. The plantaris tendon can be found on the medial edge of the Achilles tendon. It can be traced proximally as far as possible and detached as close as possible to the muscle tendon junction to gain as much length as possible.

   

  It can be left attached distally to the calcaneus, looped and woven through the proximal Achilles tendon, and sewn back onto the distal part to the tendon.

   

   

  Alternatively, the plantaris can be detached distally as well and used as a free graft. The tourniquet is deflated and the time is recorded.8

• Case Example (Courtesy of Mark E. Easley, MD)

Background and Imaging

 

A 52-year-old woman with a 2-year history of right Achilles tendon pain

 

Remote minor injury (overuse); no acute rupture

 

 

 

Several months of physical therapy and activity modification have not improved symptoms. Fusiform swelling over 5 cm of Achilles tendon, 5 to 10 cm proximal to Achilles tendon insertion Tender over area of swelling/fullness

 

 

 

Difficulty with single-limb heel rise: pain in tendon, weakness Lateral radiograph did not suggest calcification within tendon. MRI (TECH FIG 3)

 

Achilles tendon in continuity

 

 

Demonstrates fusiform fullness to tendon corresponding to area clinical findings Cyst/fluid-filled central area of tendon

 

 

 

TECH FIG 3 • A 52-year-old woman presented with chronic right Achilles tendon pain and swelling. A. Axial view demonstrating thickening of tendon and fluid-filled central area of tendon. B. Coronal view with similar findings.

C. Sagittal view also demonstrating thickened area of tendon and central cyst, starting approximately 5 cm proximal to Achilles insertion and extending at least 5 cm more proximally.

Positioning

 

Prone position

 

Important to make sure genitalia well protected and brachial plexi/ulnar nerves at elbows without tension or pressure

Exposure and Inspection

 

Posterior longitudinal incision, slightly medial to midline

 

 

Perhaps allows for better soft tissue coverage directly over tendon during closure Potentially safer with respect to more lateral course of sural nerve

 

Sural nerve identified and protected

 

Pre-Achilles fascia overlying tendon opened longitudinally

 

 

Paratenon exposed and noted to be adherent to tendon in area of symptoms Stenosing flexor tenosynovitis (TECH FIG 4A)

 

Difficult to separate from Achilles tendon (TECH FIG 4B)

 

Careful separation with scissors to expose underlying tendon (TECH FIG 4C,D)

 

 

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TECH FIG 4 • Stenosing flexor tenosynovitis. A. Adherent and diseased paratenon difficult to separate from Achilles tendon. B. Note chronically diseased paratenon directly at area of thickened Achilles tendon. C. Using scissors, careful débridement/elevation of diseased paratenon to expose Achilles tendon. D. In this case, no distinct plane between paratenon and tendon. E. Achilles tendon full exposed.

 

 

Important to full free tendon from adherent, diseased paratenon (TECH FIG 4E)

 

If adhesions persist, symptoms related to chronic paratendinopathy and stenosis will not resolve.

Achilles Tendon

 

 

Tendon markedly thickened Longitudinal fibers appear intact.

 

 

 

TECH FIG 5 • A. Cystic/fluid-filled area (noted on preoperative MRI) readily identified with careful dissection through longitudinal fibers. In this case, chronic hematoma, fibrous tissue, and scar suggestive of prior trauma and repetitive stress. B. Hematoma/cyst removed. C. Degenerated/chronic fibrous tissue excised. D. Scarred and unhealthy tendon fibers exposed. E. Unhealthy Achilles tendon débrided. F. Central diseased portion extending quite proximally. (continued)

 

Cystic/fluid-filled area (noted on preoperative MRI) readily identified with careful dissection through longitudinal fibers (TECH FIG 5A)

 

In this case, suggestive of prior trauma or repetitive stress after injury: chronic hematoma, fibrous tissue/scar, indicative of disturbed natural healing process

 

Fluid-filled “pocket” carefully débrided (TECH FIG 5B-D)

 

Unhealthy, scarred fibrous tissue carefully débrided, leaving adjacent healthy longitudinal fibers intact (TECH FIG 5E-H)

 

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TECH FIG 5 • (continued) G. Diseased tissue, with lack of longitudinal fibers, typically readily identified. H. In this case, considerable amount of unhealthy central tissue.

Residual Tendon

 

After comprehensive débridement of unhealthy tissue and central cystic area, the remaining longitudinal fibers are carefully assessed (TECH FIG 6A).

 

In this case, large central defect but ample residual healthy longitudinal fibers to consider direct repair without augmentation (TECH FIG 6B)

Tendon Repair via Tubularization

 

Central defect eliminated by tubularizing the remaining healthy tendon fibers

 

Tubularization is performed by “wrapping” one side of the tendon over the other, thereby obliterating the central defect and reinforcing the tendon at its weakest point (TECH FIG 7A).

 

 

 

TECH FIG 6 • A. After comprehensive débridement of unhealthy tissue and central cystic area, remaining longitudinal fibers carefully assessed. B. In this case, large central defect but ample residual healthy longitudinal fibers to consider direct repair without augmentation.

 

 

In this case, absorbable suture used

 

 

Several deeper interrupted approximating sutures Repair reinforced with a running suture (TECH FIG 7B)

 

Note more anatomic appearance to tendon, albeit with some residual thickening (TECH FIG 7C) Closing Paratenon and Fascial Layer over the Tendon

 

Satisfactory tendon gliding and health is optimized by closing the paratenon and fascial layer over the tendon.

 

This closure also protects the tendon should a wound complication develop.

 

 

 

TECH FIG 7 • Achilles tendon repair. A. Tubularization performed by wrapping one side of the tendon over the other to obliterate central defect and reinforcing tendon at its weakest point. B. Several deeper interrupted approximating sutures and a reinforcing running suture. C. After repair, tendon with a more physiologic appearance, albeit with some residual thickening.

 

 

30

 

In this case, there was considerable diseased paratenon that should not be left in contact with the Achilles tendon.

 

 

A healthier layer of paratenon and pre-Achilles fascia remained (TECH FIG 8A,B) The diseased paratenon was excised (TECH FIG 8C,D).

 

 

 

TECH FIG 8 • In this case, there was considerable diseased paratenon but fortunately a healthier layer of paratenon and pre-Achilles fascia. A. Lateral side. B. Medial side. Diseased paratenon was excised. C.

Diagnosis

• Diagnosis is usually made on a clinical basis, including a careful history and physical

  examination.

• Ultrasound can identify hypoechoic areas, which have been shown at surgery to consist of degenerated tissue, and increased thickness of the tendon.

• MRI studies should be performed only if the ultrasound scan remains unclear.

Positioning ▪ Prone position, with thigh tourniquet

Incision

• An incision placed medial and anterior to the medial border of the Achilles tendon

reduces the likelihood of injury to the sural nerve and short saphenous vein.

PEARLS AND PITFALLS

Lateral side. D. Medial side. Repair of healthy residual paratenon and pre-Achilles fascia. E. Careful

reapproximation without trapping the Achilles tendon. F. Care is taken to avoid injury to the sural nerve.

 

The healthy layer of residual paratenon and pre-Achilles fascia was carefully reapproximated over the repaired tendon (TECH FIG 8E,F).

Care was taken to avoid trapping the sural nerve.

Routine skin closure, dressings, and splinting

 

 

POSTOPERATIVE CARE

 

A period of initial splinting and crutch walking is generally used to allow pain and swelling to subside. In addition, wound healing complications are difficult to manage and an initial period of immobilization may promote skin healing.

 

After 14 days, the wound is inspected and motion exercises are initiated.

 

 

The patient is encouraged to start daily active and passive ankle range-of-motion exercises. The use of a removable walker boot can be helpful during this phase.

 

Weight bearing is not limited according to the degree of débridement needed at surgery, and early weight bearing is encouraged.

 

However, extensive débridements and tendon transfers may require protected weight bearing for 4 to 6 weeks postoperatively.

 

After 6 to 8 weeks of mostly range-of-motion and light resistive exercises, initial tendon healing will have been completed. More intensive strengthening exercises are started, gradually progressing to plyometrics and

eventually running and jumping.13,14

 

 

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OUTCOMES

The surgical procedure is commonly successful, but patients should be informed of the potential failure of the procedure, risk of wound complications, and, at times, prolonged recovery time.6

 

Rehabilitation is focused on early motion and avoidance of overloading the tendon in the initial healing phase.

 

 

COMPLICATIONS

Wound healing problems Infection

Sural nerve injury

Rupture of Achilles tendon Deep vein thrombosis

 

 

REFERENCES

1. Maffulli N. Re: etiologic factors associated with symptomatic Achilles tendinopathy. Foot Ankle Int 2007;28:660-661.

    

    

2. Maffulli N, Kader D. Tendinopathy of tendo achillis. J Bone Joint Surg Br 2002;84(1):1-8.

    

    

3. Maffulli N, Kenward MG, Testa V, et al. Clinical diagnosis of Achilles tendinopathy with tendinosis. Clin J Sport Med 2003;13:11-15.

    

    

4. Maffulli N, Khan KM, Puddu G. Overuse tendon conditions: time to change a confusing terminology. Arthroscopy 1998;14:840-843.

    

    

5. Maffulli N, Reaper J, Ewen SW, et al. Chondral metaplasia in calcific insertional tendinopathy of the Achilles tendon. Clin J Sport Med 2006;16:329-334.

    

    

6. Maffulli N, Sharma P, Luscombe KL. Achilles tendinopathy: aetiology and management. J R Soc Med 2004;97:472-476.

    

    

7. Maffulli N, Testa V, Capasso G, et al. Calcific insertional Achilles tendinopathy: reattachment with bone anchors. Am J Sports Med 2004;32:174-182.

    

    

8. Maffulli N, Testa V, Capasso G, et al. Results of percutaneous longitudinal tenotomy for Achilles tendinopathy in middle- and long-distance runners. Am J Sports Med 1997;25:835-840.

    

    

9. Maffulli N, Testa V, Capasso G, et al. Similar histopathological picture in males with Achilles and patellar tendinopathy. Med Sci Sports Exerc 2004;36:1470-1475.

    

    

10. Maffulli N, Testa V, Capasso G, et al. Surgery for chronic Achilles tendinopathy yields worse results in nonathletic patients. Clin J Sport Med 2006;16:123-128.

     

     

11. Maffulli N, Wong J. Rupture of the Achilles and patellar tendons. Clin Sports Med 2003;22:761-776.

     

     

12. Maffulli N, Wong J, Almekinders LC. Types and epidemiology of tendinopathy. Clin Sports Med 2003;22:675-

    692.

     

     

13. Rompe JD, Nafe B, Furia JP, et al. Eccentric loading, shock-wave treatment, or a wait-and-see policy for tendinopathy of the main body of tendo Achilles: a randomized controlled trial. Am J Sports Med 2007;35: 374-383.

     

     

14. Sayana MK, Maffulli N. Eccentric calf muscle training in nonathletic patients with Achilles tendinopathy. J Sci Med Sport 2007; 10:52-58.