How To Address The Neglected Achilles Tendon Rupture

Given the common presentation of neglected Achilles tendon ruptures, these authors discuss signs and symptoms, and keys to diagnosis. They also survey the literature and offer their perspectives on excision with direct repair and performing a flexor hallucis longus transfer.

A neglected Achilles tendon rupture is one that has gone without treatment for more than four weeks.1 It is common to see neglected Achilles tendon ruptures in foot and ankle practices around the country.

   Why is this the case? There are two reasons. Acute Achilles tendon ruptures are occasionally missed or misdiagnosed in emergency rooms and urgent care centers. Alternately, the patient may not bother to seek care due to the fact that the pain is often tolerable and the limb still functions well enough for ambulation.

   It may be weeks or months before the patient is referred or decides to seek treatment from a foot and ankle specialist. Most of the patients presenting with Achilles tendinopathy, whether they do so post-rupture or not, are individuals who maintain an active lifestyle, recreationally or competitively.2 Achilles tendinopathy is described as pain, limitation of activities and swelling related to tendon degeneration.3 In regard to the incidence of Achilles rupture, it reportedly occurs in 18 out of 100,000 people, mostly athletic men in their 20s and 30s.4

   The Achilles tendon is the strongest and thickest tendon in the human body. However, the amount of force placed across it at times can unfortunately lead to rupture. Currently, many surgeons advocate surgical repair in the acute setting. Surgical repair offers decreased re-rupture rates in comparison to non-operative care. Researchers have documented rates as high as 10 to 30 percent with conservative efforts along with decreased functional outcomes.5

   Researchers have shown that non-operative treatment can lead to a decrease in plantarflexion and decreased stamina in comparison to a surgically repaired Achilles.6 Early weightbearing is crucial to facilitate proper healing and full functional return, and surgical repair allows earlier range of motion.

   The suspected mechanism for rupture is excessive muscle contraction with a lack of inhibition, most often occurring on an already degenerative tendon. The Achilles tendon can be damaged with or without rupture. Various authors have suggested several possible causes for Achilles tendinopathy. These potential causes include overuse, decreased blood supply and collagen change with age, muscle imbalance, insufficient flexibility, and malalignment.

Essential Diagnostic Insights

The presenting symptoms vary depending on multiple factors. The rupture may be a partial rupture, including multiple foci of “micro-tears.” In this subset, tendon healing/remodeling has likely faltered, leading to pain and/or a soft, non-functioning tendon. Both lipoid and mucoid degeneration can occur with the former having fatty deposits and the latter having a soft grey/brown appearance.7

   The healing mass may itself become painful at a bulbous segment, which one would usually note around the midsubtance or watershed area, 2 to 6 cm proximal to the Achilles insertion. Clinicians can observe abnormal (nonparallel) neovascularization and varicose nerve fibers where poor healing has occurred.8

   Also bear in mind that neurotransmitters such as glutamate have recently been isolated in elevated concentrations in pathologic tendon tissues and may relate to pain in a degenerative Achilles.9 Similar to a complete rupture, this variant may also have a strength deficit during propulsion.

   Following a complete rupture, symptoms may parallel the former with an addition of inappropriate posterior group tensioning, including weakness and over lengthened tendon healing. Patients may complain of unsteady gait, difficulty with step climbing, a limp with ambulation and difficulty with heel rise. Classically, this is why the patient seeks treatment. The patient may notice weakness from the previous baseline and a difference from his or her contralateral limb. Not infrequently, the patient does not recall the actual rupture or simply did not realize its severity and failed to seek guidance.

   The physical exam may show a palpable gap or conversely a bulbous segment where irregular regeneration has occurred, depending on the length of delay of the presentation. Increased dorsiflexion in comparison to the contralateral ankle with diminished plantarflexion strength is common. Pain may or may not be present. Propulsion is ineffective and one often sees a calcaneal gait. Gastrocsoleus muscle atrophy may also present as the deep flexors serve to plantarflex at the ankle instead of the gastrocsoleal muscle group. This combines with scarring to create a wasting effect.

   The physical exam is sufficient when there is an acute Achilles rupture. However, when there is a neglected rupture, obtaining magnetic resonance imaging (MRI) can be helpful in determining the extent of Achilles tendon damage. If there is a partial rupture of less than 50 percent of the tendon on transverse or cross sectional views, one should exhaust conservative efforts as they can facilitate dramatic improvements.

   When examining Achilles tendinopathy (non-rupture patients), Magnussen and colleagues assessed the literature and determined eccentric rehabilitation for three to six months can have positive outcomes.10 One can expect success rates with conservative care to range between 30 to 50 percent when less than 50 percent of the tendon is affected.11,12 Achilles tendon rehabilitation addresses inflammation, weakness, flexibility and biomechanical malalignments.

   If the MRI reveals greater than 50 percent cross sectional tendon involvement and there is accompanying pain and/or disability, one may consider surgical repair. When functional deficit and weakness exist, MRI is not as critical and one can make decision to proceed to surgery clinically.

   However, even in the presence of over-lengthened tendon healing and functional failure, obtaining a MRI can assist with determining the extent of involved tendon derangement and can facilitate procedure choice. Also, the MRI serves to confirm viability of the flexor hallucis longus (FHL) tendon in case of transfer.

   We do not recommend corticosteroid injections for the Achilles tendon for the known risks of collagen weakening and ultimate rupture. Relative contraindications to surgical intervention include: arterial insufficiency; superficial infection; inadequate soft tissue envelope; and poor medical condition. One must also consider age and functional demands.

   Ultimately, the decision to perform surgery for a neglected Achilles tendon rupture is based on a discussion with the patient to determine functional goals and the known risks involved. Surgical complications can be expected following an Achilles repair. Paavola and co-workers reported an 11 percent complication rate in 432 patients.11 Their complications included skin necrosis, superficial wound infections, seroma formation, hematoma, scarring, sural nerve irritations, tendon rupture and deep vain thrombosis.

A Guide To Excision With Direct Repair

When it comes to neglected Achilles tendon ruptures, we target two surgical strategies. The first option is excision with direct repair and possible proximal lengthening. The second option is excision and tendon transfer. Surgeons may utilize biologics, including acellular matrices and bone marrow aspirate/stem cells, with any of the techniques to increase healing potential.

   For the subset of patients with localized, persistent mid-substance pain and no functional deficit, one would perform a direct repair. The goal is resection of the degenerative segment and removal of adhesions surrounding the tendon. The technique we employ is a slightly medial to midline longitudinal incision overlying the degenerative segment and down to the paratenon.

   One would subsequently observe the paratenon and incise it in line with the tendon. Surgeons will often encounter adhesions and can utilize a combination of sharp and blunt dissection methods to free them. Pay attention to the ventral surface as well as adhesions and inflamed tissue that may be present.

   Split the tendon longitudinally at the bulbous section. One can subsequently view the diseased portion of the Achilles and excise it as an ellipse. Be sure to extend proximal and distal enough to normal appearing tendon. Assess the extent and nature of the tendon. If there is minimal damage and sufficient strength and diameter of tendon remain, one can repair the tendon with a running vicryl suture and include paratenon repair during the full thickness closure.

   When the tendon has more extensive damage, surgeons may employ biologic augmentation. One may apply the acellular matrix in one of two methods. Surgeons can incorporate the matrix into the substance of the tendon at the elliptical excision site and perform a subsequent repair with the remaining tendon. We call this the “prosciutto’”method.
Alternately, the surgeon can apply and secure the matrix to the repaired tendon. One can also add bone marrow aspirate to the matrix to facilitate matrix activation. This brings in the necessary healing agents to an otherwise avascular zone. In addition, surgeons may perform a longitudinal deep fasciotomy to allow for added envelope for closure and increased blood flow to the repair.

   The variant direct repair option addresses the diseased tendon by completely excising a segment of tendon. The amount of tendon one removes depends upon the tendon appearance, the amount of over-lengthening and involvement on preoperative MRI. The surgeon then performs a primary, end-to-end tendon repair, similar to an open acute rupture repair. We utilize a classic Krackow technique. If the resection is too extensive due to the diseased portion, one would perform a V to Y lengthening in a more proximal direction. Again, surgeons would often perform an adjunctive deep fasciotomy and utilize biologic augmentation.

Pertinent Pearls On The FHL Transfer

The second surgical option, the FHL transfer, is our most commonly performed procedure for those who have severe disease in greater than 50 percent of the tendon and those who have an elongated Achilles tendon.13 The FHL is adjacent, assessable and sufficiently strong to replace or assist with an ineffective Achilles. The transfer technique is straightforward and quick with some advances in technique over the last few years. These advances include a short single incision harvest and fixation with an interference screw.14

   One would access the Achilles with a longitudinal incision at the medial border of the Achilles. The surgeon proceeds to excise the degenerative tendon (often the entire tendon). If a portion of normal appearing tendon remains, it may require advancement of this tendon and a direct repair to shorten the over-lengthened tendon. The deficit may be substantial and one may add a synthetic matrix to avoid a notable dell at closure.

   To locate the FHL tendon, incise the deep fascia longitudinally and mobilize the hallux. Follow the FHL tendon along the medial calcaneus. Be sure to isolate just the tendon. Transect the FHL as distal as possible against the calcaneus. Place a whip stitch and pass the tendon through a drill hole created from dorsal to plantar at the most posterior aspect of the calcaneus. Perform appropriate resection of the Achilles in order to allow for FHL placement with an interference screw. It is critical to achieve sufficient tension to afford the FHL a mechanical advantage to replace the much larger Achilles.

   One can also perform side-to-side repair with the transferred FHL and the Achilles if a portion of the Achilles tendon remains. The foot should have a plantarflexed attitude and the surgeon should splint this in equinus to protect the transfer. Afterward, patients may notice a decrease in muscle strength, particularly at the hallux interphalangeal joint. However, they should still be able to perform the single heel rise effectively. Will and Galey reported good to excellent outcomes in 19 FHL transfers with no complications.15

Key Post-Op Principles

Regardless of the technique surgeons employ, the postoperative protocol remains the same. Postoperatively, there should be three weeks of non-weightbearing. One should apply a splint in the OR.

   This is followed by cast application at visit one and initiation of a removable boot with a heel wedge protocol for three weeks. This includes beginning with three 10-degree heel wedges, removing one weekly and subsequently initiating weightbearing. At six weeks, the patient can begin physical therapy with a return to activities at four months.

Final Notes

The neglected Achilles tendon rupture is a common finding. This is usually a clinical diagnosis with advanced imaging offering final details. At times, conservative efforts can be successful. In regard to determining whether surgical intervention is necessary, it is best to offer an explanation of risks and benefits to the patient, and ascertain the functional goals of the patient. When the patient elects to have surgery, the needs of the particular limb clearly indicate the procedural choice. Direct excision and repair is useful and the FHL transfer is a reproducible, successful procedure.

   Dr. Bussewitz is a fellowship-trained foot and ankle surgeon who is currently in private practice in Iowa City, Iowa.

   Dr. Philbin is a fellowship-trained foot and ankle surgeon who is currently in private practice in Westerville, Ohio.

References

1. Gabel S, Manoli A 2nd. Neglected rupture of the Achilles tendon. Foot Ankle Int 1994; 15(9):512–517.
2. Kujala UM, Sarna S, Kaprio J. Cumulative incidence of Achilles tendon rupture and tendinopathy in male former elite athletes. Clin J Sport Med. 2005; 15(3):133-135.
3. Jarvinen TA, Kannus P, Maffulli N, Kahn KM. Achilles tendon disorders: etiology and epidemiology. Foot Ankle Clin, 2005; 10(2):255-266.
4. Gebauer M, Beil FT, Beckmann J, Sárváry AM, Ueblacker P, Ruecker AH, Holste J, Meenen NM. Mechanical evaluation of different techniques for Achilles tendon repair. Arch Orthop Trauma Surg. 2007; 127(9):795–9.
5. Strauss EJ, et al. Operative treatment of acute Achilles tendon ruptures: an institutional review of clinical outcomes. Injury. 2007;38(7):832–8.
6. Kocher MS, Bishop J, Marshall R, Briggs KK, Hawkins RJ. Operative versus nonoperative management of acute Achilles tendon rupture: expected-value decision analysis. Am J Sports Med. 2002; 30(6):783–90.
7. Khan KM, Cook JL, Bonar F, Harcourt P, Astrom M. Histopathology of common tendinopathies. Update and implications for clinical management. Sports Med. 1999; 27(6):393-408.
8. Bjur D, Alfredson H, Forsgren S. The innervation pattern of the human Achilles tendon: studies of the normal and tendinosis tendon with markers for general and sensory innervation. Cell Tissue Res. 2005; 320(1):201-206.
9. Alfredson H, Thorsen K, Lorentzon R. In situ microdialysis in tendon tissue: high levels of glutamate, but not prostaglandin E2 in chronic Achilles tendon pain. Knee Surg Sports Traumatol Arthrosc. 1993; 7(6):378-381.
10. Magnussen RA, Dunn WR, Thomson AB. Nonoperative treatment of midportion Achilles tendinopathy: a systematic review. Clin J Sport Med 2009; 19(1):54-64.
11. Paavala M, Kannus P, Paakkala T, Pasanen M, Järvinen M. Long-term prognosis of patients with Achilles tendinopathy. An observational 8-year follow-up study. Am J Sports Med 2000; 28(5):634-42.
12. Johnston E, Scrantoin P Jr, Pfeffer GB. Chronic disorders of the Achilles tendon: results of conservative and surgical treatments. Foot Ankle 1997; 18(9):570-4.
13. Den Hartog BD. Flexor hallucis longus transfer for chronic Achilles tendinosis. Foot Ankle Int 2003; 24(3):233-7.
14. DeCarbo WT, Hyer CF. Interference screw fixation for flexor hallucis longus tendon transfer for chronic Achilles tendonopathy. J Foot Ankle Surg. 2008; 47(1);69-72.
15. Will RE, Galey SM. Outcome of single incision flexor hallucis longus transfer for chronic Achilles tendinopathy. Foot Ankle Int 2009; 30(4):315-7.

   For further reading, see “Current Concepts In Treating Achilles Tendon Ruptures” in the September 2009 issue of Podiatry Today, “Should You Cast Achilles Tendon Ruptures?” in the June 2008 issue or “Conquering Achilles Tendonitis In Athletes” in the November 2002 issue.