Chronic Achilles Tendon Rupture

Introduction

There is no consensus regarding the specific time in which an acute becomes a chronic rupture, although 4 weeks (or according to some authors, 6 weeks) may be the most widely accepted interval. 

Even though Achilles tendon ruptures are frequent and are usually not difficult to diagnose in experienced hands, more than 20% of acute injuries are misdiagnosed, leading to a chronic rupture.

The management of chronic Achilles tendon ruptures is technically more demanding than the primary repair of acute ruptures. Primary repair is not generally possible, because of the increased gap between the two tendon ends.

 

Clinical Presentation and Assessment

The diagnosis of chronic Achilles tendon rupture is more difficult than in acute ruptures. A tendon gap may be absent because of formation of scar tissue. Active plantar flexion of the foot may be preserved because of the function of tibialis posterior, peroneal tendons, and the long toe flexors. Calf muscle weakness, Achilles tendon elongation and a limp can be observed. The affected leg should be compared with the contralateral leg.

 

​Imaging​

Although clinical examination is the gold standard, however imaging is useful for the diagnosis of chronic Achilles tendon chronic (more for medico-legal purposes than for clinical indications). Plain lateral radiographs may reveal an irregular configuration of the fat-filled triangle of Kager. Ultrasonography usually shows an acoustic vacuum with thick irregular edges. T1-weighted MRI shows disruption of signal within the tendon substance, whereas T2-weighted images show generalized high signal intensity.

Conservative Treatment

The best functional outcomes are achieved through surgical reconstruction but non-surgical treatment may be preferable for patients with poor skin condition, history of smoking, soft tissue complications from previous surgery, poorly controlled long-standing diabetes and compromised anaesthetic or surgical fitness.

Conservative treatment could be as simple as lace up ankle brace or custom made leather ankle brace. In patients with severe Achilles dysfunction, an AFO can be considered. Any bracing method can be coupled with physiotherapy to strengthen the gastrocnemius and recruitment of the entire deep posterior compartment muscles.

There is no study that stratifies non-operative versus operative treatment for chronic Achilles tendon rupture.

 

Surgical Treatment

Different surgical techniques have been described to address chronic ruptures. Due to lack of RCTs and smaller numbers in the available series, a standard recommended procedure is lacking.

Potential contraindications for surgical intervention include systemic diseases (poorly controlled), smoking (relative), and concern about noncompliance or adherence to the necessary postoperative course.

Surgical options for reconstruction include fascial advancement, tendon transfers (peroneus brevis, FDL or FHL transfer), fascial advancement with tendon transfer, graft augmentation, and ankle fusion. Fascial advancements alone can be utilized for mild to moderate gapping.

With mild gaps (2-3 cm) a gastrocnemius recession, or V-Y advancement can provide the necessary length for end-to-end repair.

Moderate gaps (4-5 cm) often require fascial advancement with a central turndown flap.

Large gaps (5 cm or greater) usually require a combination of reconstruction techniques such as fascial advancement, tendon transfer, graft augmentation, or tendon allograft.

The main concerns of these techniques include wound breakdown and infections, which occasionally may require plastic surgical procedures to cover significant soft tissue defects.

Less invasive procedures of peroneus brevis and flexor hallucis longus (FHL) transfer have been described, which allow reconstruction preserving local skin integrity.

The choice of the surgical technique is not based on the patient’s demands, but on the characteristics of the rupture and surgical findings. If the gap is less than 6 cm, a peroneus brevis transfer can easily be performed for Achilles tendon reconstruction, but if the gap is greater than 6 cm this technique is not sufficient to fill the gap, and a semitendinosus tendon transfer is recommend.

The ultimate determinant of a good result is the capability to do a single limb heel-rise. In most cases, this is attainable around 6 months postoperatively.

 

Surgical Options

FHL Transfer

The use of FHL tendon has become popular in the repair of the neglected Achilles tendon rupture. In part it is due to the mechanical advantage compared to the other autologous transfers, as it has been shown to be stronger than the PB and almost twice as strong as the FDL tendon. It is active during the same phase as the triceps surae complex and helps maintain normal ankle function.

It can be sewn to the Achilles in a side-to-side fashion, or transferred directly to the calcaneus. The average tendon length from the posterior incision was 5.16 cm compared to 8.09 cm that can be obtained from a separate medial incision in a study by Tashijan et al.

Good results have been reported with FHL transfer. 

The FHL is a strong, long tendon and allows bridging of large gaps. The muscle itself is able to produce force that supplements the strength exerted by the gastrocnemius-soleus complex. Some authors prefer not to use FHL in high-demand running and sprinting athletes, who necessitate being able to grip the ground in a powerful fashion, and therefore, the loss of flexion of the interphalangeal joint of the hallux would be detrimental to performance. However, in general population, FHL transfer can be used with excellent results.

Elias et al. described FHL transfers and V-Y lengthening in 15 patients with chronic Achilles ruptures (an average gap of 5-8 cm). Postoperative analysis showed 22% loss of plantarflexion strength, and a 5-degree loss of ankle range of motion with good functional scores.

Peroneous Brevis Transfer

The PB tendon transfer is an effective technique to repair a chronic Achilles tendon rupture when the gap between the two tendon ends is smaller than 6 cm. This technique was originally popularised by Perez-Teuffer, who passed the tendon through an osseous tunnel in the calcaneum. Subsequently Turco and Spinella modified this technique by passing the PB tendon through the stump of the Achilles tendon. The routine use of peroneus brevis is not widely practiced because of the loss of eversion and presumed frontal plane stability.

Maffulli et al. reported good results in 32 patients who underwent surgical reconstruction using peroneus brevis tendon transfer. At final follow-up, all patients were able to walk on tiptoes returned to their pre-injury occupation. No re-ruptures and major complications were seen. Four patients (12%) experienced a superficial infection which was managed with systemic antibiotics and local dressings. A hypertrophic scar in the area of the Achilles tendon distal surgical wound was reported in 5% of cases.

Gallant et al., in their study, found mild objective eversion and plantar flexion weakness after reconstruction using PB. Subjective assessment revealed no functional compromise.

More recently, excellent results have been recently reported in 17 patients by Maffulli et al. with a mean follow-up of 4.6 years, and most patients being able to return to pre-injury sport and daily activities, and 10 of 13 patients being able to return to recreational activities. In this series, no wound breakdown, infections and re-ruptures were reported.

Aggarwal et al. reported the results of 20 patients who underwent reconstruction using PB tendon. Four patients developed superficial infection, of which 1 required skin grafting. No patient had re-rupture of the tendon. At one year follow-up, all patients achieved good functional outcomes.

For eversion, the PB tendon contributes 28% of the total working strength, therefore, after PB transfer, the strength of eversion might be slightly weakened. However, the peroneus longus, being the stronger evertor, takes over the function of eversion fully.

FDL tendon transfer

The use of FDL tendon has been advocated as it mimics the course of the Achilles tendon without comprising the lesser digit function postoperatively. The use of this tendon also avoids the loss of eversion and ankle balance seen with transfer of the PB. Mann et al. first described the technique in 7 patients with duration of symptoms ranging from 3 to 36 months with an average follow-up of 39 months. They achieved excellent result in 4 patients, good in 2, and fair in 1. The 6 patients who achieved good to excellent result were all able to return to pre-injury activities without pain. Two patients with good result had wound complications requiring a secondary procedure. No re-ruptures were reported in their series and active plantarflexion of the digits were preserved and no hammer-toe deformities were seen postoperatively.​

Ipsilateral Free Semitendinosus Tendon Graft

If the gap between the proximal and distal stumps is greater than 6 cm despite maximal plantar flexion of the ankle and traction on the tendon stumps, an ipsilateral semitendinosus tendon graft is indicated.

Maffulli et al reported excellent results in 26 patients who were treated with minimally invasive semitendinosis graft. The average follow-up was 8.2 years. All patients returned to their pre-injury occupation, and 22 patients returned to their pre-injury level of activity at a mean of 6.7 months after surgery. The authors reported rate of superficial infection of 7.6%. One patient developed scar adhesions to the distal wound. No deep infections, wound breakdown, rupture or detachment were reported.

Synthetic Graft

Several synthetic materials have been used with success in some early studies. These include vascular grafts, carbon fiber composites, polyglycol threads, and polyester mesh. The advantage of using synthetic materials is that they avoid sacrificing other active tendons and their function. 

In turn, the morbidity associated with larger incisions and dissections involved in autologous techniques can be bypassed. However, the use of synthetic materials in this area well-known for tenuous wound healing, is a major disadvantage and a discouraging factors for most surgeons. Foreign body reaction has been observed with the use of carbon or polyester fibre.

Lee et al. reported on 9 patients who underwent primary repair of a neglected Achilles rupture with augmentation by an acellular dermal matrix graft. The follow-up ranged from 20 to 30 months with no incidence of re-rupture. All patients were able to perform single heel raise on the reconstructed side.

 

Complications

Wound problems are not uncommon after the repair of a chronic rupture. The local blood supply to the posterior aspect of the leg is often precarious and may be further disrupted by surgical intervention, introduction of foreign material such as allograft and the denser scar tissue that diminishes the healing capability of the skin.​

If the tendon complex is too tight, then the patient will have some difficulty in attaining a plantigrade foot. Extensive physical therapy may diminish some of the equinus position but generally the resultant deformity is not easily treatable because the resultant scar tissue that forms in the gap has a more limited capacity to stretch than native tissue.

The incidence of re-rupture is far less after repair of a chronic rupture compared to repair of the acute rupture, the incidence is not zero.

 

References

  • Maffulli N. A Giai Via, F. Oliva. Achilles Tendon Rupture. In: Volpi P, Ed. Arthroscopy and Sport Injuries: Applications in High-level Athletes, Cap 10. Springer 2015.
  • Maffulli N, Via AG, Oliva F. Chronic Achilles Tendon Disorders: Tendinopathy and Chronic Rupture. Clin Sports Med 2015; 34(4): 607-24.
  • Wapner KL, Pavlock GS, Hecht PJ, Naselli F, Walther R. Repair of chronic Achilles tendon rupture with flexor hallucis longus tendon transfer. Foot Ankle 1993; 14(8): 443-9.
  • Pintore E, Barra V, Pintore R, Maffulli N. Peroneus brevis tendon transfer in neglected tears of the Achilles tendon. J Trauma 2001; 50(1): 71-8.
  • Maffulli N, Del Buono A, Spiezia F, Maffulli GD, Longo UG, Denaro V. Less-invasive semitendinosus tendon graft augmentation for the reconstruction of chronic tears of the Achilles tendon. Am J Sports Med 2013; 41(4): 865-71.
  • Maffulli N, Longo UG, Gougoulias N, Denaro V. Ipsilateral free semitendinosus tendon graft transfer for reconstruction of chronic tears of the Achilles tendon 2008; 8: 90-100.
  • Gallant GG, Massie C, Turco VJ. Assessment of eversion and plantar flexion strength after repair of Achilles tendon rupture using peroneus brevis tendon transfer. Am J Orthop 1995; 24(3): 257-61.
  • Maffulli N, Loppini M, Longo UG, Maffulli GD, Denaro V. Minimally invasive reconstruction of chronic achilles tendon ruptures using the ipsilateral free semitendinosus tendon graft and interference screw fixation. Am J Sports Med 2013; 41(5): 1100-7.
  • Gallant GG, Massie C, Turco VJ. Assessment of eversion and plantar flexion strength after repair of Achilles tendon rupture using peroneus brevis tendon transfer. Am J Orthop 1995; 24(3): 257-61.
  • Pérez Teuffer A.; Traumatic rupture of the Achilles Tendon. Reconstruction by transplant and graft using the lateral peroneus brevis, Orthop Clin North Am. 1974 Jan;5(1):89-93.
  • Turco V1, Spinella AJ.; Peroneus brevis transfer for Achilles tendon rupture in athletes, Orthop Rev. 1988 Aug;17(8):822-4, 827-8.
  • Elias I, et al. Reconstruction for missed or neglected achilles tendon rupture with v-y lengthening and flexor hallucis longus transfer through one incision. Foot Ankle Int 2007;29:1238-48.
  • Robert P. Taylor, Neglected Achilles Tendon Ruptures: Surgical Considerations.
  • Dalton, G. (1996). Achilles tendon rupture. Foot Ankle Clin, 1, pp. 225-236.
  • Lee, D. (2007). Achilles tendon repair with acellular tissue graft augmentation in neglected ruptures. J Foot Ankle Surg, 46, 6, pp. 451-455.
  • Mann, R.; Holmes, G. & Seale, K. (1991). Chronic rupture of the Achilles tendon: a new technique of repair. J Bone Joint Surg, 73A, pp. 214–219.
  • Tashjian, R.; Hur, J.; Sullivan, R.; Campbell, J. & DiGiovanni, C. (2003). Flexor hallucis longus transfer for repair.
  • Jake Lee and John M., Schuberth, Surgical Treatment of the Neglected Achilles Tendon Rupture.