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2008;90:1348-1360.  doi:10.2106/JBJS.G.01241 J Bone Joint Surg Am.Nicola Maffulli and Adam Ajis    

Management of Chronic Ruptures of the Achilles Tendon

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www.jbjs.org20 Pickering Street, Needham, MA 02492-3157The Journal of Bone and Joint Surgery

Current Concepts Review

Management of Chronic Rupturesof the Achilles Tendon

By Nicola Maffulli, MD, MS, PhD, FRCS(Orth), and Adam Ajis, MRCSEd

� Chronic ruptures of Achilles tendons are those that present four to six weeks after the original injury. They havebecome more common as acute Achilles tendon injuries have become more frequent, and they are associated withconsiderable functional morbidity.

� Most surgeons agree that chronic ruptures should be managed operatively.

� Diagnosis is based predominantly on history and clinical examination. Real-time, high-resolution ultrasound andmagnetic resonance imaging are helpful in preoperative planning or as a diagnostic aid.

� Local tissue, local tendons, and allografts can be used to reconstruct the tendon, and end-to-end repair is possibleif the gap is <2.5 cm.

� Compared with acute injuries, chronic injuries are associated with a higher rate of postoperative infection andmore prolonged recovery.

Ruptures of the Achilles tendon are especially common inmiddle-aged men who occasionally participate in sports1-4. Insome cases, a patient sustains a rupture, but this is not diag-nosed and the patient presents with a chronic rupture four tosix weeks later5-10. Although there is still much controversy abouthow to manage acute ruptures, most surgeons agree thatchronic ruptures should be treated operatively when possible,as they are associated with considerable functional morbidity.An ankle-foot orthosis can be used to manage a chronic rup-ture in a low-demand individual or in a patient in whom oper-ative management is contraindicated.

PathophysiologyA chronic rupture of the Achilles tendon causes difficultywith and impairment of ankle plantar flexion11. The tendonsheath often becomes thickened and adherent to the retractedends of the tendon, and there is minimal repair tissue in thegap11-13.

The proximal stump is often conical14 and adherent tothe fascia posterior to the flexor hallucis longus muscle belly12.

The distal stump often looks bulbous. If the plantaris tendon ispresent, it may be hypertrophied.

Thickened scar tissue commonly bridges the rupturesite13,15-17 in an attempt at repair18. A well-organized connectivetissue repair response was seen fifty-six days after resection ofcalcaneal tendons in rabbits, but a fascicular arrangement ofcollagen fibers typical of a tendon was still not present by 240days19. The repair tissue is not as strong as intact tendon, and itelongates with time13,20.

Retraction of the proximal stump results in shorteningof the intact proximal gastrocnemius-soleus complex. This re-duces its biomechanical efficiency and the contractile forcethat the muscle can develop. The overall effect is weakness ofankle plantar flexion and hence a flat-footed, nonpropulsivegait on the affected side.

DiagnosisChronic Achilles tendon ruptures normally present as a resultof a misdiagnosed, neglected, or unrecognized acute rupture.Patients may describe a sudden sharp pain in the calf, as if

Disclosure: The authors did not receive any outside funding or grants in support of their research for or preparation of this work. Neither they nor amember of their immediate families received payments or other benefits or a commitment or agreement to provide such benefits from a commercialentity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, division, center, clinical practice,or other charitable or nonprofit organization with which the authors, or a member of their immediate families, are affiliated or associated.

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J Bone Joint Surg Am. 2008;90:1348-60 d doi:10.2106/JBJS.G.01241

kicked from behind21, while they were engaged in sports ac-tivity. Alternatively, they may recall a minor injury with aninitial episode of heel pain. Subsequently, routine daily taskssuch as walking uphill or climbing stairs become difficult3.

Diagnosing an acutely ruptured Achilles tendon is usu-ally straightforward if the history and findings on examinationare clear. Nevertheless, as much as a fifth of these lesions can bemissed22. In one study, nine (36%) of twenty-five elderly pa-tients had a delay of more than one week before treatmentbecause the condition was not diagnosed at the time of injury23.

When a patient has a chronic rupture, the pain and swell-ing have often subsided and the gap between the tendon endshas filled in with fibrous tissue23-25 (Fig. 1). In addition, activeplantar flexion, although weak, may be possible through theaction of the tibialis posterior, flexor hallucis longus, flexordigitorum longus, and peroneal muscles. These residual func-tions may make it difficult to confirm the correct diagnosisthrough clinical examination alone26. A limp is often present27.A high index of suspicion is needed, and a range of special testsand investigations can aid in accurate diagnosis.

Clinical ExaminationOn inspection, there may be a visible gap at the rupture site.The calf muscles may be wasted. The long toe flexors mayaccommodate for the lack of function of the gastrocnemius-soleus complex, producing clawing of the toes and an appar-ently higher medial arch of the foot.

The clinical tests described here have been systematicallystudied for the diagnosis of acute ruptures; their applicabilityto chronic cases has, to our knowledge, not been investigated.

The calf squeeze test, also known as the Thompson test,was first described by Simmonds in 195728. The patient liesprone on the examination table with both feet over the edge.The calf is squeezed and, if the Achilles tendon is intact, thefoot will plantar flex as the tendon connects the gastrocnemius-soleus complex to the calcaneus. When the tendon is torn, andthus no longer connects the gastrocnemius-soleus complex tothe calcaneus, the foot will not plantar flex as much as it does onthe normal side.

The Matles test29 is also performed with the patient lyingprone. The knees are flexed to 90�. The ankle on the rupturedside will assume a more dorsiflexed position as compared withthe normal side. This is due to the absence of normal tensionunder which the tendon connects the gastrocnemius-soleuscomplex to the calcaneus and hence the effects of gravity makethe foot dorsiflex more on the injured side.

With the O’Brien needle test30, also done with the patientprone, a hypodermic needle is inserted off the midline 10 cmproximal to the calcaneal insertion of the Achilles tendon, suchthat its tip lies within the substance of the tendon. The ankle isthen manually plantar flexed and dorsiflexed by the examiner.If, on dorsiflexion, the pin moves so that it points proximally,the area of tendon between the pin and calcaneus is presumedto be intact; if not, then a rupture is probable.

Fig. 1

Typical appearance of a chronic rupture of the Achilles tendon. Note the gap between the bulbous

distal stump of the tendon and the proximal stump (arrow) on this photograph made immediately

before surgery. The patient, a forty-two-year-old woman, sustained the tear thirteen weeks before

surgery.

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Copeland described a test performed with a sphygmo-manometer31. A sphygmomanometer cuff is wrapped aroundthe midpart of the calf with the patient lying prone. The cuff isinflated to 100 mm Hg (13.3 kPa) with the foot in plantarflexion. The foot is then dorsiflexed by the examiner. If thepressure rises to approximately 140 mm Hg (18.7 kPa), themusculotendinous unit is presumed to be intact. If the pres-sure on dorsiflexion remains approximately the same, a rup-ture is presumed.

If two of the tests described above are positive, a diag-nosis of a ruptured Achilles tendon is certain24.

ImagingLateral radiographs of the ankle can be used to aid in thediagnosis of a ruptured Achilles tendon. For example, Kager’striangle32, a small fat-filled space between the anterior aspectof the Achilles tendon, the posterior part of the tibia, and thesuperior aspect of the calcaneus, can become distorted. Also,deformation of the distal tendon contours due to loss of tonecan be seen15. Radiographs can further aid in diagnosis byruling out other diagnoses such as calcaneal avulsions or otherosseous injuries26. Calcification in the distal stump of theAchilles tendon is sometimes seen in patients with a chronicrupture. In one study, three of seven patients had evidence ofthis on plain radiographs27.

Real-time, high-resolution ultrasonography is inexpen-sive, rapid, and dynamic33. However, it is highly user-dependent,requiring training and experience to correctly interpret the

images. A linear-array transducer probe is held perpendicularto the skin overlying the tendon. Ultrasound gel is used toensure that the optimal amount of energy is returned to thetransducer probe, enabling good dynamic and panoramic im-ages of the tendon34,35. The longitudinal collagen fibers in theAchilles tendon reflect ultrasonic energy, and high-frequencyprobes show the tendon best36. A normal tendon appears asa hypoechogenic, ribbon-like image contained between twohyperechogenic bands. These bands are separated when thetendon is relaxed and are more compact when the tendon isunder tension. When the Achilles tendon is ruptured, ultra-sonography shows tendon discontinuity with decreased or in-creased echogenicity, depending on the chronicity of therupture37 (Fig. 2).

Magnetic resonance imaging can show in detail the con-dition of the ends of completely ruptured tendons38. A normalAchilles tendon is viewed as an area of low signal intensity on allsequences. It tapers smoothly with no focal defects. The darkband of the tendon itself can be distinguished from the highsignal intensity of the pre-Achilles fat pad38. Chronic rupturesare seen as an area of low signal intensity on T1-weighted imagesand as discontinuity and altered signal on T2-weighted scans.The condition is best appreciated on sagittal views (Fig. 3).

ManagementManagement of chronic Achilles tendon ruptures is challeng-ing. The ends of the tendon are frequently retracted and havean atrophic appearance.

Fig. 2

A real-time, high-resolution longitudinal ultrasound scan of a seventeen-week-old chronic

rupture of the Achilles tendon in a fifty-five-year-old man. Note the loss of the normal

contour of the tendon, with hyperechogenicity, and a bulbous appearance of the distal

stump (arrow).

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Conservative ManagementChristensen reported on a series of fifty-one patients with fifty-seven ruptures39, nearly two-thirds of which were chronic.Eighteen of these ruptures were treated conservatively, eitherbecause the operation was contraindicated or refused (sevenruptures) or because the rupture was several months old andthe triceps surae showed clinical signs of regaining strengthand hence the injury was managed without any further con-servative or surgical intervention (eleven ruptures). The resultwas satisfactory (i.e., the gait was normal, the patient returnedto his or her previous occupation, and there was slight or nodiscomfort) in ten of these eighteen nonoperatively treatedcases. The improvement occurred slowly, sometimes overseveral years, in all of these cases. These results comparedpoorly with those in the patients who were managed surgically.

The outcome was satisfactory in twenty-nine of the thirty-ninecases in which operative treatment was performed.

A brace or ankle-foot orthosis can be beneficial for pa-tients who undergo conservative management13.

Operative ManagementTo our knowledge, there are no evidence-based guidelines forchoosing the type of operative management of chronic rup-tures of the Achilles tendon. Two classification systems havebeen proposed13,40. With both, management is based on thelength of the tendon defect, but to our knowledge the results ofthe implementation of these guidelines have not been assessed,not even by the authors reporting them.

In Myerson’s classification13, a Type-1 defect is no morethan 1 to 2 cm long. It is managed with end-to-end repair and

Fig. 3

Sagittal magnetic resonance imaging scan of a fifteen-week-old chronic rupture

of the Achilles tendon in a fifty-one-year-old man. The tendon tear had healed in

continuity. Note the thickening of the tendon (solid arrow) and the areas of

fluid and disordered healing both proximally and close to the insertion

(dashed arrow).

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a posterior compartment fasciotomy. A Type-2 defect rangesbetween 2 and 5 cm. It is managed with V-Y lengthening, withor without a tendon transfer. A Type-3 defect is >5 cm and isbridged with use of a tendon transfer, alone or in combinationwith a V-Y advancement.

In Kuwada’s classification40, a Type-I lesion is a partialrupture and is managed with plaster cast immobilization. AType-II lesion is a complete rupture with a defect of up to 3 cmin length. It is managed with end-to-end repair. A Type-III le-sion is a complete rupture with a defect of 3 to 6 cm afterdebridement of the tendon ends to healthy tissue. It is managedwith a tendon graft, with or without augmentation with a syn-thetic graft. Finally, a Type-IV lesion is a complete rupture witha defect of >6 cm in length after debridement of the ends of thetendon to healthy tissue. A gastrocnemius recession, a free ten-don graft, and/or a synthetic tendon graft are used for this typeof lesion.

V-Y Tendon AlignmentThis procedure was first described by Abraham and Pankovichfor the treatment of chronic Achilles tendon ruptures41. Theaim is simply to achieve anastomosis of the tendon ends bymaking an inverted V-shaped incision in the proximal part ofthe tendon and repairing it in a Y-shaped fashion. Three offour patients in their study regained full strength of the tricepssurae and were able to perform a single-leg heel-raise as well asthey could on the normal side. The remaining patient hadslight weakness of the triceps surae and a much decreasedability to perform the single-leg heel-raise. Follow-up in thissmall series ranged from nine to fifteen months.

Leitner et al.42 reported good results in three patients inwhom a tendon defect of 9 to 10 cm had been managed withthis technique. Kissel et al.43 used this technique, with aug-mentation with the plantaris tendon and a pullout suture,successfully in fourteen patients. Parker and Repinecz44 de-scribed a similar procedure (a modified Strayer gastrocnemiusrecession) whereby a tongue-in-groove advancement of thegastrocnemius aponeurosis was used to close a 6.5-cm defectin one patient. They reported this to be technically easier thana V-Y advancement and claimed that 50% more length couldbe achieved.

None of these studies were well designed or well con-ducted, and none involved a sufficiently large number of pa-tients to allow us to draw useful conclusions.

Turndown FlapsChristensen39 described a technique that he used for bothchronic and acute tendon ruptures. A distally based 2 by 10-cmflap was fashioned in the proximal part of the tendon andturned down to cover the defect. The defect produced by theflap was also closed. Twenty-nine of thirty-nine patients in thatseries were reported as having a satisfactory outcome.

Silfverskiold45 described a similar procedure, but he rotatedthe flap 180� so that the smooth tendon surface stayed superficial.Modifying this further, Arner et al.15 used two flaps, one medialand the other lateral, and rotated both, in opposite directions.

Gerdes et al.46 showed, in a cadaver study, that flap-augmentedrepairs had a 41% higher tensile strength than end-to-end repairsalone (217.5 ± 44.7 N compared with 153.9 ± 30.2 N).

Rush17 used the aponeurosis of the gastrocnemius-soleusmuscle complex fashioned into a tube to reconstruct anAchilles tendon with a neglected rupture. Five patients had agood result with this technique. Bosworth20 showed, in a groupof seven patients, that a strip of the superficial part of theproximal Achilles tendon stump can be used to augment therepair. A strip of proximal tendon on a distal pedicle isthreaded through the trimmed ends of the ruptured tendonand sutured to them. No complications were reported after anaverage duration of follow-up of ten years.

V-Y and turndown flaps have been combined, with goodresults47. In a series of six patients who underwent postoper-ative isokinetic strength testing, deficiencies in peak torqueplantar flexion were found to range from 2.5% to 22% com-pared with values for the unaffected limb.

Mulier et al.48 reported on nineteen patients with achronic Achilles tendon rupture involving a defect of >2 cm.Ten patients were treated with a gastrocnemius turndown flap(group 1), and nine patients were managed with a combina-tion of a flexor hallucis longus transfer and a gastrocnemiusturndown flap (group 2). At eighteen months, the outcomeswere better in group 2. Subjective assessment showed that 40%of the patients in group 1 and 33% of those in group 2 had adecline in daily and sports activities. Objective assessment withisokinetic dynamometry at twelve months postoperativelydemonstrated a 23% deficit in power and strength in group1 compared with a 14% deficit in group 2. The range of anklemotion (compared with that on the contralateral side) was70% in group 1 and 76% in group 2. The overall complicationrate was high in this study, with seven of nineteen patientsexperiencing problems.

Peroneus BrevisThe peroneus brevis tendon was popularized by PerezTeuffer49. He harvested this tendon from its attachment at thebase of the fifth metatarsal and passed it through a trans-osseous drill hole in the calcaneus. The tendon was then passedback on itself and sutured over the Achilles tendon. Thisprocedure was used in thirty patients, all of whom had an acutetendon rupture, and twenty-eight of them were able to returnto their original level of sports activity. This procedure hassubsequently been used for chronic tears.

Turco and Spinella26 augmented an end-to-end repair ofthe Achilles tendon with a modification of Perez Teuffer’stechnique, by passing the tendon of the peroneus brevisthrough the distal stump rather than through the calcaneus.Excellent results were reported, but the outcome measureswere not identified. Miskulin et al. also passed peroneus brevisthrough the distal Achilles tendon stump and used plantaristendon as suture material50. In their series of five patients, allpatients had an improvement in peak plantar flexion torque(range, 21% to 410%) and no complications were reported atone year after the operation.

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McClelland and Maffulli51 approached the Achilles tendonmedially, and pulled the stump of the peroneus brevis throughthe inferior peroneal retinaculum, hence retaining its bloodsupply from the intermuscular septum. The tendon of theperoneus brevis was then woven through small coronal incisionsin the distal stump of the Achilles tendon and again throughsimilar incisions in the proximal stump. If the plantaris musclewas present, its tendon was used to augment the repair.

Some investigators reported concerns that this techniquecould result in eversion weakness of the ankle13,27,52. However,the peroneus longus muscle has more than twice the eversionstrength of the peroneus brevis. Theoretically, if the tendon ofthe peroneus brevis is placed distally in a lateral-to-medialdirection, it does not duplicate the medial pull of an intactAchilles tendon27. However, the practical implications of thesemechanical studies are unclear, and reconstruction with useof the tendon of the peroneus brevis has been reported to befunctionally successful.

Pintore et al.53 compared the results of treatment of acuteruptures with direct end-to-end anastomosis with the resultsof treatment of chronic ruptures with peroneus brevis transfer.At the time of follow-up, at a mean of fifty-three months, theyfound the patients who had had a chronic rupture to be sat-isfied with the result of the procedure despite experiencing ahigher postoperative complication rate and greater loss ofstrength and calf circumference compared with their coun-terparts who had had an acute rupture.

Flexor Digitorum LongusMann et al.27 used the flexor digitorum longus tendon as a graftin a series of seven patients. A medial hockey-stick-shapedincision was used to approach the Achilles tendon, and anotherincision was used to identify the flexor digitorum longustendon extending from the navicular to the first metatarso-

phalangeal joint. The flexor digitorum longus tendon was thentransected before it divided into its separate digital branches,and its distal stump was sutured to the adjacent flexor hallucislongus tendon. The distal end of the flexor digitorum longustendon was then delivered through the proximal wound overthe Achilles tendon. The free end of the flexor digitorumlongus tendon was next passed through the distal end of theAchilles tendon with use of small coronal incisions and againrouted proximally and passed through similar incisions in theproximal end of the Achilles tendon. A proximal fascial turn-down flap was used to augment the repair in all patients. Six ofthe seven patients had a good or excellent result, with no re-ruptures and no functional disability from loss of the flexordigitorum longus tendon. The average duration of follow-upin this series was thirty-nine months.

Flexor Hallucis LongusThe flexor hallucis longus muscle has a long (10 to 12-cm)tendon that can be used to bridge a large Achilles tendondefect. When transferred, it also maintains the normal musclebalance of the ankle—i.e., a plantar flexor is transferred to aplantar flexor. However, athletic patients have reported that theloss of push-off strength from the hallux causes difficultyduring sprinting51. Wapner et al.52 used the flexor hallucislongus tendon as a graft in seven patients who were then fol-lowed for an average of seventeen months. Once the tendonwas harvested, the surgeons passed it through a drill hole in thecalcaneus and wove it through the ruptured ends of theAchilles tendon. The distal end of the flexor hallucis longustendon was tenodesed to the tendon of the flexor digitorumlongus to the second toe. As determined from a subjectivequestionnaire, three patients had an excellent result, three hada good result, and one had a fair result. All patients had afunctionally unimportant loss of the ranges of motion of both

Fig. 4

The use of a free gracilis tendon to reconstruct an Achilles tendon with a chronic rupture.

Note the 7-cm defect in the Achilles tendon after freshening of the stumps. The free gracilis

tendon is being passed through the distal stump of the Achilles tendon.

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the ankle and the hallux. Isokinetic testing revealed a 29.5%reduction in plantar flexion power compared with the value onthe normal side. No functional disability was measured sec-ondary to harvesting of flexor hallucis longus. This observationis similar to that reported in 1977, when Frenette and Jackson54

found no functional loss in ten young athletes with lacerationsof the flexor hallucis longus tendon, four of which were notrepaired.

Advantages of flexor hallucis longus transfer include thetendon being long and durable and the muscle is stronger thanthat of other transfer candidates55, the axis of flexor hallucis

longus contraction most closely resembles that of the Achillestendon, and contraction of the flexor hallucis longus occurs inphase with the gastrocnemius-soleus complex. Its anatomicalproximity makes the operative technique easier, without theneed to open other compartments, and the muscle belly aids inthe provision of a vascular supply to the distal stump of theAchilles tendon.

GracilisMaffulli and Leadbetter56 reported harvesting gracilis tendonto reconstruct chronically ruptured Achilles tendons. If, de-

Fig. 5-A

Figs. 5-A through 5-D Performance of a z-shortening procedure for the treatment of a

chronic Achilles tendon tear that had healed in continuity. Following a longitudinal

tenotomy along the entire length of the tendon, the tendon is shortened in a z fashion.

Fig. 5-A The proximal limb is being shortened.

Fig. 5-B

The distal limb is being shortened.

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spite maximal ankle plantar flexion and traction on the rup-tured stumps, the gap between the two ends of the Achillestendon was seen to be >6 cm, the investigators harvested thegracilis tendon and used it in the reconstruction. An incisionover the pes anserinus was used, and the tendon was harvestedwith a tendon stripper (Fig. 4). If plantaris tendon was present,it could be used to augment the repair. Of twenty-one patientsfollowed for a mean of twenty-eight months after this proce-dure, two had an excellent result, fifteen had a good result, andfour had a fair result56.

Fascia LataUse of fascia lata to repair and augment a ruptured Achillestendon has produced good results11,14,57. Bugg and Boyd58 re-ported the outcomes of repairs of twenty-one ruptures orlacerations, ten of which were chronic. They bridged the gap inthe Achilles tendon with three strips of fascia lata and with asheet of fascia lata sutured around these grafts in a tube-likefashion, with the serosal surface facing outward and the seamplaced anteriorly and sutured to the proximal and distalstumps. A wire pullout suture was also used. No formal results

Fig. 5-C

A line drawing depicting the z-shortening procedure.

Fig. 5-D

The completed procedure.

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were reported, but two case reports stated that the techniqueprovided satisfactory function and cosmetic results at twelvemonths postoperatively.

AllograftsNellas et al.59 reported using two strips of freeze-dried Achillestendon allograft in a single patient to reconstruct a 4.5-cmtendon defect following debridement of an infected woundafter a primary repair. At the time of follow-up at thirtymonths, the patient had a good functional result but persistentweakness compared with the strength on the uninjured side.

More recently, Haraguchi et al.60 used Achilles tendon al-lografts to reconstruct both chronically ruptured Achilles ten-dons with a defect of >5 cm and Achilles tendons with extensivetendinopathy. In this procedure, cortical bone is removed fromthe patient’s heel to allow room for the allograft, which is se-cured in position with two 4.0-mm screws. The graft is thenplaced under tension and repaired to the native Achilles tendon.No formal results were reported and the duration of follow-upwas not mentioned, but neither rejection of the allograft nortransmission of disease to the host was observed.

Synthetic GraftsUse of synthetic materials avoids complications with donor sitemorbidity but increases the theoretical risk of infection.Howard et al.61 used a carbon-fiber synthetic graft to repair fiveneglected ruptures. After four to nineteen months of follow-up, the average plantar flexion strength was 88% comparedwith that of the contralateral ankle (40.8 kg compared with45.46 kg). All patients had an excellent result.

Parsons et al.62 used an absorbable carbon-fiber com-posite polymer in a series of forty-eight patients with a total offifty-two Achilles tendon ruptures, twenty-seven of which werechronic. The polymer ribbon was woven through both theproximal and the distal stump of the tendon with six, seven, oreight passes to bridge the defect. A proximal tendon flap wasused at the surgeon’s discretion. According to the authors’ ownunvalidated scoring system, forty-five (87%) of fifty-two re-constructions yielded a good or excellent result at a minimumof one year. It was not stated how many ruptures were acuteand how many were chronic. Complications included tworeruptures, two deep infections, and three superficial infec-tions. An investigation of the use of carbon fiber in sheeptendons showed carbon fiber fragmentation to be associatedwith poor collagen production63. With implantation of poly-ester fibers, the neotendon was more dense, had more collagen,and was more closely adherent63.

Ozaki et al.64 used three layers of polypropylene mesh totreat neglected ruptures with gaps ranging between 5 and 12cm in six patients. At the time of follow-up, at a minimum of2.4 years, all patients showed satisfactory function and plantarflexion strength averaged 94% of that on the uninjured side.No complications were noted in the series.

Dacron vascular grafts have been employed to augmentrepairs of Achilles tendon ruptures65,66 and have yielded goodor excellent results when used for acute ruptures.

Jennings and Sefton9 used polyester tape with a Bunnell-type suture in the treatment of sixteen chronic ruptures. Thetape was tensioned so that the ankle could just dorsiflex toneutral. One patient required removal of the tape, one had asural nerve injury, and three had superficial wound infection.No reruptures occurred during the mean follow-up period ofthree years.

Interposed Scar TissueYasuda et al.67 noted that the thick fibrous scar tissue foundbetween the two ends of a ruptured Achilles tendon was strongenough to resist substantial tensile forces. They also hypoth-esized, on the basis of animal and clinical studies, that theinterposed scar tissue would be able to form tendon-like repairtissue. All of their patients underwent magnetic resonanceimaging preoperatively. The investigators only studied patientswho were seen to have a thickened tendon, with diffuse high-intensity signal changes throughout, on T2-weighted images.This is thought to indicate active scar formation and healingwith dense collagen fibers and proliferating fibroblasts andvessels. Six patients were included in the series. The investi-gators resected the middle third of the interposed scar tissueand anastomosed the two free ends with Krackow-style su-tures68 running at least 2 cm into the native tendon. Histo-logical examination of the resected tissue showed densecollagen fibers with blood vessels and no degenerative changes.In two specimens, these fibers were found to run parallel to thelong axis of the tendon with rows of fibroblasts lying in be-tween. In the remaining four specimens, the dense collagenfibers were not oriented along the axis of the tendon butcontained highly cellular fibrovascular tissue. After surgery, nopatient had difficulty walking or stair-climbing, and all wereable to perform a single-limb toe rise. The mean AmericanOrthopaedic Foot and Ankle Society ankle-hindfoot scoreswere 88.2 points preoperatively and 98.3 points at an averageof thirty-one months postoperatively, and the difference wassignificant (p = 0.05).

Chronic Achilles Tendon Tears That Have Healed in ContinuityIn some patients, the Achilles tendon tear may have healedand the tendon presents no gap on inspection and palpation.However, the patient has lengthening of the gastrocnemius-soleus-Achilles tendon complex, the Matles test is positive,the calf squeeze test findings are dubious, and there is amarked decrease in push-off ability. In these instances,the tendon may appear intact at surgery but, on opening ofthe paratenon, there is evidence of scarring over a long seg-ment. In such patients, we perform a z-shortening procedure(Figs. 5-A through 5-D), making sure that the shorteningproduces greater equinus than is present on the contralateralside.

Minimally Invasive and Endoscopic ManagementIn patients with a chronic rupture, the skin over the gap re-tracts over several weeks and remains retracted until the timeof the operation. During surgery, this skin is incised and is then

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stretched in a relatively acute fashion to make space for thereconstructed tendon. Therefore, following the reconstruction,the skin over the gap may well be stretched so much that itsvascular supply is impaired. Reconstruction techniques involveuse of relatively long incisions and are prone to be complicatedby wound breakdown. Some authors have incorporated skin-flap techniques to facilitate closure following reconstructiveprocedures for the Achilles tendon69.

To avoid this problem in patients with a chronic rupturein whom a gap is palpable, we do not expose the tendon gap.Instead, we make a 5-cm longitudinal incision 2 cm proximaland just medial to the palpable end of the proximal stump. Thesecond incision is 3 cm long and is also longitudinal but is 2 cmdistal and lateral to the distal end of the tendon rupture. Care istaken to prevent damage to the sural nerve by making thisincision as close as possible to the anterior aspect of the lateralborder of the Achilles tendon. The distal stump of the Achilles

tendon is then mobilized, freeing it of all of the peritendinousadhesions, particularly on the lateral side. This allows access tothe lateral base of the distal tendon stump close to its insertion.The ruptured tendon end is then resected back to healthytendon, and a number-1 Vicryl locking suture (polyglactin;Ethicon, Edinburgh, United Kingdom) is run along the freetendon edge to prevent separation of the bundles. The proxi-mal tendon stump is then mobilized from the proximalwound, and adhesions are divided. Further soft-tissue releaseanterior to the gastrocnemius-soleus muscle allows maximalexcursion, minimizing the gap between the two tendonstumps. AVicryl locking suture is run along the free edge of thetendon to allow adequate exposure and to prevent separationof the bundles. To bridge the gap, we use the tendon of theperoneus brevis, which we harvest in a standard fashion51. Theperoneus brevis muscle is then mobilized proximally to pro-vide increased excursion. With use of a number-11 blade, a

Fig. 6-A Fig. 6-B

Fig. 6-C

Figs. 6-A, 6-B, and 6-C The two-incision tech-

nique for reconstruction of a chronically torn

Achilles tendon with a gap of up to 6 cm. Fig. 6-A

The two incisions over the Achilles tendon. The

distal stump has been prepared, and the proximal

stump has been delivered through the proximal

wound and its end has been freshened. Fig. 6-B

The tendon of the peroneus brevis has been

identified at the base of the fifth metatarsal and

is being harvested. Fig. 6-C The tendon of the

peroneus brevis and its muscle belly have been

delivered through the proximal wound and is

ready for the transfer procedure.

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longitudinal tenotomy parallel to the tendon fibers is madethrough both stumps of the tendon. An artery clip is used todevelop the plane, from lateral to medial, in the distal Achillestendon stump, and the peroneus brevis graft is passed throughthe tenotomy site. With the ankle in plantar flexion, a number-1Vicryl suture is used to suture the peroneus brevis to both sidesof the distal stump. The tendon of the peroneus brevis is thenpassed beneath the intact skin bridge into the proximal inci-sion and is passed from medial to lateral through atransverse tenotomy in the proximal stump and is further se-cured with a number-1 Vicryl suture. Finally, the tendon of theperoneus brevis is sutured back onto itself on the lateral side ofthe proximal incision (Figs. 6-A, 6-B, and 6-C).

Recently, Lui70 described a technique for endoscopicassisted transfer of the tendon of the flexor hallucis longus tominimize soft-tissue dissection in the treatment of chronicAchilles tendon tears. The procedure is performed with use ofvery small incisions (<1.5 cm each), but it is unclear whetherthe continuity of the Achilles tendon is adequately restored andfunctional recovery would have to rely solely on the flexor hal-lucis longus. Nevertheless, the technique is minimally invasiveand minimizes injury to the soft tissues. Three cases of chronicAchilles rupture were described. At a mean of fifteen monthspostoperatively, none of the patients walked with a limp.

Postoperative ManagementWe are not aware of any studies focusing specifically onpostoperative management following operative treatment ofchronic Achilles tendon ruptures. However, the present trendis for early mobilization after the operative repair of acuteruptures71. Recent meta-analyses have shown that early func-tional treatment protocols, when compared with postoperative

immobilization, led to more excellent subjective responses andno difference in the rerupture rate72. We use the same protocolfor chronic ruptures: the patient wears a below-the-knee castfor two weeks and is encouraged to bear as much weight aspossible on the operatively treated limb as soon as possible71.At two weeks, the cast is removed and a lower leg anteriorsplint is applied, allowing the ankle to be plantar flexed fullybut not dorsiflexed and allowing inversion and eversion. Theseexercises are performed against manual resistance. At sixweeks, the anterior splint is removed, and the patient graduallyreturns to his or her normal activities. Recovery can take aslong as nine to twelve months.

The FutureTissue engineering may prove useful for managing tendonruptures in the future. In one study, 1-cm-long rabbit Achillestendon defects were core bridged with a polydioxanone sutureand then encapsulated in human amnion extracellular matrixseeded with third-passage fetal skin fibroblasts73. There weretwo control groups. In control group I, defective tendons werecore bridged with a polydioxanone suture and encapsulatedwith human amnion extracellular matrix without fibroblasts.In control group II, the defects were only core bridged withpolydioxanone suture. Gross examination, light microscopy,immunohistochemical examination, scanning electron micros-copy, and biomechanical measurement of the repaired tendonswere performed at one, two, and three months postoperatively.The optimal cell concentration for seeding fibroblasts was 3.5 ·106 cells/mL. Cells grew well on the extracellular matrix. Im-munohistochemistry showed that the labeled seed fibroblastsplayed an important role in tendonization. The rate andquality of healing in the experimental group were superior tothose in both control groups. The values for the structural andmaterial properties of the implants that had received humanamnion extracellular matrix seeded with third-passage fetalskin fibroblasts typically were approximately twice those of thecontrols, and the repaired tendons were larger in cross sectionand better organized histologically than the repairs performedwith suture alone. The tensile strength in the experimentalgroup was the greatest, at 81.8% of normal after three months.The authors concluded that human amnion extracellularmatrix seeded with third-passage fetal skin fibroblasts pro-motes rapid repair of a tendon defect.

In another study, polyglycolic acid scaffolds seeded withtenocytes were implanted into hen flexor tendon defects74.Twelve weeks after the operation, the tenocytes and collagenfibers became longitudinally aligned. At fourteen weeks, thetissue-engineered tendons displayed a typical tendon structurewith a breaking strength of 83% of normal.

A potential application of mesenchymal stem cells is exvivo, de novo tissue engineering. This technique involves con-struction of whole body tissues in the laboratory and their subse-quent implantation into patients. Such tissue-engineered tendonspotentially could be used to bridge large areas of tissue loss.

Tissue engineering is an emerging field, and many dif-ficulties need to be overcome before this approach becomes a

TABLE I Recommendations for the Treatment of Chronic

Ruptures of the Achilles Tendon

Grade ofRecommendation Recommendations

C We advocate a low threshold for tendontransfer in the operative managementof chronic Achilles tendon rupture

C If an end-to-end repair is not possible,our procedure of choice is transfer ofthe tendon of the peroneus brevis. Ifthe gap is too large to be bridged bythe peroneus brevis tendon, the tendonof the flexor digitorum longus can beharvested and used to bridge the gap

C We recommend avoiding syntheticgrafts because high complicationrates have been described

C We recommend using gracilis orsemitendinosus grafts for defectsof >6.5 cm if local viable tendonsare insufficient

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real option in the management of tendon disorders. For ex-ample, effective vascularization and innervation of implantedtissue-engineered constructs must take place. Vascularizationis important for the viability of the construct. Innervation isrequired for proprioception and to maintain reflexes that aremediated by Golgi tendon organs to protect tendons fromexcessive forces75.

OverviewChronic Achilles tendon ruptures are uncommon but poten-tially debilitating. The choice of management is partly guidedby the type of tendon lesion76, with most injuries requiringoperative management77. Many techniques can be used to re-pair or reconstruct a tendon with a chronic rupture. It is dif-ficult to compare different techniques. Most studies have beenretrospective and small and have focused on the results of asingle technique (Table I). Functional outcome measures have

also been diverse, given the highly variable outcome criteriathat have been applied. Tissue engineering shows promise, butadditional research and clinical trials are needed to evaluate itsefficacy in humans. n

NOTE: The authors thank Dr. Paola Casillo for the help with the illustrations.

Nicola Maffulli, MD, MS, PhD, FRCS(Orth)Department of Trauma and Orthopaedic Surgery,Keele University School of Medicine, Thornburrow Drive,Hartshill, Stoke on Trent ST4 7QB Staffs, England.E-mail address: n.maffulli@keele.ac.uk

Adam Ajis, MRCSEdDepartment of Trauma and Orthopaedic Surgery,Macclesfield District General Hospital, Victoria Road,Macclesfield SK10 3BL, England

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