Direct Repair of Chronic Achilles Tendon Ruptures Using Scar Tissue Located Between the Tendon Stumps

1168 COPYRIGHT Ó 2016 BY THE OURNAL OF BONE AND OINT SURGERY, INCORPORATED Direct Repair of Chronic Achilles Tenon Ruptures Using Scar Tissue Locate Between the Tenon Stumps Toshito Yasua, MD, Hiroaki Shima, MD, Katsunori Mori, MD, Momoko Kizawa, MD, an Masashi Neo, MD Investigation performe at the Department of Orthopeic Surgery, Osaka Meical College, Osaka, apan Backgroun: Several surgical proceures for chronically rupture Achilles tenons have been reporte. Resection of the interpose scar tissue locate between the tenon stumps an reconstruction using normal autologous tissue have been well escribe. We evelope a irect repair proceure that uses scar tissue, which obviates the nee to use normal autologous tissue. Methos: Thirty consecutive patients with Achilles tenon ruptures with a elay in iagnosis of >4 weeks unerwent removal of a section of scar an healing tissue with irect primary suture of the ens of the tenon without the use of allograft or autograft. Patients were followe for a mean time of 33 months. Preoperative an postoperative clinical outcomes were measure with the Achilles Tenon Total Rupture Score (ATRS) an the American Orthopaeic Foot & Ankle Society (AOFAS) ankle-hinfoot score. In aition, the patients unerwent preoperative an postoperative functional measurements an magnetic resonance imaging. Lastly, we evaluate the histology of the interpose healing tissue. Results: The mean AOFAS scores were 82.8 points preoperatively an 98.1 points postoperatively. The mean postoperative ATRS was 92.0 points. At the time of the latest follow-up, none of the patients ha experience tenon reruptures or ifficulties in walking or climbing stairs, an all except 2 patients coul perform a single-limb heel rise. All athletes ha returne to their pre-injury level of sports participation. Preoperative T2-weighte magnetic resonance imaging showe that 22 Achilles tenons were thickene with iffuse intrateninous high-signal alterations, an 8 Achilles tenons were thinne. Postoperative T2-weighte magnetic resonance imaging finings inclue fusiform-shape tenon thickening an homogeneous low-signal alterations of the tenons in all patients. Histologically, the interpose scar tissue consiste of ense collagen fibers. Conclusions: Shortening of the tissue between the 2 tenon ens that inclue healing scar an irect repair of healing tenon without allograft or autograft can be effective for treatment-elaye or neglecte Achilles tenon rupture. Level of Evience: Therapeutic Level IV. See Instructions for Authors for a complete escription of levels of evience. Peer review: This article was reviewe by the Eitor-in-Chief an one Deputy Eitor, an it unerwent bline review by two or more outsie experts. The Deputy Eitor reviewe each revision of the article, an it unerwent a final review by the Eitor-in-Chief prior to publication. Final corrections an clarifications occurre uring one or more exchanges between the author(s) an copyeitors. Numerous surgical proceures have been reporte for the reconstruction of a chronic Achilles tenon rupture 1-23 ; these involve resection of the interpose scar tissue an reconstruction using normal autologous tissue. Although these reconstructive surgical proceures have been shown to have goo clinical results, they are time-consuming an ifficult to perform compare with primary repair. In aition, proceures involving the use of a normal autologous tenon are associate with onor-site morbiity 24. The gap between the tenon stumps in chronic Achilles tenon rupture is reporte to be fille with interpose scar tissue 4,5,7,8,21,25,26. The histology of healing tenon shows thick collagen fibers with highly cellular fibrovascular tissue 25.If interpose scar tissue has a similar histology, the sacrifice of normal tissues coul be obviate. An experimental stuy in a rabbit moel emonstrate that the scar tissue between the tenon stumps evolves to tenon tissue over time 27. Moreover, in a clinical stuy, histologic examination showe that the Disclosure: There were no external funing sources. The Disclosure of Potential Conflicts of Interest forms are provie with the online version of the article. Bone oint Surg Am. 2016;98:1168-75 http://x.oi.org/10.2106/bs.15.00865

1169 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG surgical biopsy specimen obtaine from the scar tissue containe a prominent granulation tissue response 26. These results suggest that scar tissue can be use in the repair of a chronically rupture Achilles tenon. Accoringly, in 2001, we evelope a irect repair proceure for chronic Achilles tenon rupture that involves the use of interpose scar tissue. We reporte the clinical results of reconstruction for 6 chronic Achilles tenon ruptures 28 ; the interpose scar tissue coul be utilize for chronic Achilles tenon rupture repair if preoperative magnetic resonance imaging (MRI) showe that the Achilles tenon was fusiformshape. Although this series yiele goo clinical results, postoperative MRI finings were not evaluate. Thus, we use interpose scar tissue to perform reconstruction of consecutive chronic Achilles tenon ruptures associate with tenon thickening or thinning on preoperative MRI. Furthermore, we evaluate tenon healing using postoperative MRI. We aime to escribe our surgical proceure an prospectively review its outcomes. Aitionally, preoperative an postoperative MRI finings an histologic features of the scar tissue locate between the tenon stumps are escribe. Our hypothesis was that our irect repair proceure using the interpose scar tissue coul be effectively use for reconstructing chronic Achilles tenon rupture. Materials an Methos This stuy was conucte in accorance with the Worl Meical Association Declaration of Helsinki. All patients provie informe consent an this stuy was approve by our institutional review boar. From February 2001 through December 2012, 31 consecutive patients with a chronic Achilles tenon rupture unerwent irect tenon repair using interpose scar tissue locate between the stumps. All patients unerwent a surgical proceure performe by one of the authors. The inications for a surgical proceure were a symptomatic chronic Achilles tenon rupture with isability involving activities of aily living (i.e., walking an climbing stairs) an a limp. A limp was efine as an asymmetric gait with poor push-off or failure of push-off (plantar flexion weakness) on the involve sie. All patients coul not perform a single-limb heel rise an 22 patients ha pain. All patients reporte muscle weakness uring the push-off phase of walking an esire surgical treatment. Conservative treatment, incluing an ankle-foot orthosis or arch supports, ha faile in these patients. All patients with chronic Achilles tenon rupture for >4 weeks after injury were inclue 4,10,26. Chronic Achilles tenon rupture was iagnose preoperatively on the basis of a positive Thompson test, the inability to perform a single-limb heel rise, limping, an preoperative MRI finings. Exclusion criteria were Achilles tenon rerupture, a previous surgical proceure on the affecte Achilles tenon, an corticosteroi therapy for other illnesses. One patient (1 foot) was lost to follow-up because she ha move an coul not be contacte. The remaining 30 patients (30 feet) were 16 men an 14 women with a mean age of 52.7 years; they were available for follow-up for at least 2 years (Table I). The mean boy mass inex was 23.8 kg/m 2. With regar to comorbiities, 6 patients ha hypertension, 5 ha hyperlipiemia, an 3 ha iabetes. There were 2 smokers. With regar to occupation, 9 patients were office workers, 8 were workers who performe their work while staning up, 6 were homemakers, an 3 were stuents. The patient group inclue 3 competitive athletes (1 college basketball player, 1 high school basketball player, an 1 semiprofessional baseball player) who participate in sports every ay an 11 recreational athletes who participate in sports once or twice a week. Of the 30 patients, 13 ha a neglecte Achilles tenon rupture an 17 ha a misiagnose Achilles tenon rupture. Some misiagnose patients were treate with a posterior splint or an ankle brace for 1 to 2 weeks. We efine patients with a neglecte Achilles tenon rupture as those who i not see a octor within 4 weeks after injury. In 27 patients, the TABLE I Characteristics of Patients Characteristics Patients (N = 30) Sex* Male 16 (53.3%) Female 14 (46.7%) Age (yr) 52.7 (17 to 78) Sie* Right 17 (56.7%) Left 13 (43.3%) Boy mass inex (kg/m 2 ) 23.8 (17.4 to 30.0) Smokers* 2 (6.7%) Athletes* Competitive 3 (10.0%) Recreational 11 (36.7%) Reasons for chronic rupture* Neglect 13 (43.3%) Misiagnosis 17 (56.7%) Time from injury to the surgical 22 (5 to 70) proceure (wk) Length of gap (mm) 43.3 (25 to 80) Length of excise scar tissue (mm) 26.1 (15 to 50) Follow-up perio (mo) 33 (24 to 43) *The values are given as the number of patients, with the percentage in parentheses. The values are given as the mean, with the range in parentheses. uration from injury to the time of the surgical proceure was >12 weeks, an the mean uration was 22 weeks (range, 5 to 70 weeks). The mean postoperative follow-up perio was 33 months (range, 24 to 43 months). Clinical Evaluation All patients were clinically evaluate preoperatively an every 6 months thereafter until the most recent follow-up examination. We evaluate subjective outcomes, incluing pain, functional eficit (i.e., walking an climbing stairs), an return to sports activities accoring to a questionnaire. Objective outcomes, incluing active range of motion of the ankle, the ability to perform a single-limb heel rise, an maximum calf circumference, were investigate. Range of motion was measure by placing one goniometer arm parallel to the fibula an the other goniometer arm parallel to the long axis of the fifth metatarsal. The fulcrum of the goniometer was locate below the lateral malleolus. Active orsiflexion an plantar flexion were measure. All measurements were performe at least twice until 2 reproucible measurements within 1 of each other were achieve. To assess the function of the reconstructe gastrocnemius-soleus-achilles tenon complex, patients were aske to perform 10 single-limb heel rises on the affecte sie an were assesse as being either able or unable to o so 11-13. Patients were allowe to place 2 fingertips per han, at shouler height, on the wall for balance. Calf atrophy was assesse by measuring the maximum calf muscle circumference in both legs. We confirme the istance from the patellar apex to the point of measurement in both legs for stanarization. The measurements were repeate consecutively 3 times for each patient, an the ata were registere. The mean of the 3 values was recore as the calf circumference for stanarization. Also, we evaluate the clinical results using the American Orthopaeic Foot & Ankle Society (AOFAS) ankle-hinfoot scale 29 an the Achilles Tenon Total Rupture Score (ATRS) 30,31 at the time of the latest

1170 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG Fig. 1 Fig. 2 Fig. 1 Operative photograph showing the gap between the tenon stumps fille with scar tissue (ouble-heae arrow). Fig. 2 Operative photograph showing irect repair incorporating the scar tissue interpose between the tenon stumps. The repair was performe by placing Krackow sutures of no.-2 nonabsorbable polyfilament in each tenon stump an in the scar tissue. follow-up. We use the apanese version of the ATRS questionnaire. ATRS questionnaires were answere by 24 of the 30 patients at the most recent follow-up. Preoperative an Postoperative MRI All patients unerwent MRI for an evaluation of the contour an signal intensity of the Achilles tenon preoperatively an at 6 an 12 months postoperatively. The uration from preoperative MRI to the time of the surgical proceure was <4 weeks. A 1.5-T scanner (GE Signa HDxt 1.5T [GE Meical Systems], Siemens 1.5T Symphony [Siemens]) was use. T1 an T2-weighte images in the axial an sagittal planes were examine. We calculate the interobserver reliability to evaluate the contour an signal changes with MRI using 10 preoperative images an 10 postoperative images Fig. 3-A Fig. 3-B Figs. 3-A an 3-B T2-weighte MR images of the tenons of a 34-year-ol woman showing fusiform-shape tenon thickening. Fig. 3-A Preoperative image also showing iffuse intrateninous high-signal alterations at 4 months after injury. Fig. 3-B Postoperative image also showing homogeneous low-signal alterations at 6 months postoperatively.

1171 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG of patients in the present stuy. The ientification labels of all of the MR images were remove. Two foot an ankle surgeons inepenently assesse the contour an signal changes on MRI. Tenon thickening was efine as the narrowest part of the tenon in the sagittal plane being 1 cm, an tenon thinning was efine as the narrowest part of the tenon in the sagittal plane being <1 cm. Histologic Examination A specimen of interpose scar tissue locate between the tenon stumps was obtaine for histologic examination from each patient. The scar tissue specimen was fixe in 20% buffere neutral formalin, was ehyrate, an was embee in paraffin. Longituinal sections of the scar tissue were staine with hematoxylin an eosin an examine histologically. Surgical Technique The surgical proceure was performe with the patient in the prone position. A longituinal incision was mae along the posteromeial aspect of the Achilles tenon. Both the paratenon an the interpose scar were incise longituinally about 2 to 3 mm eep, an we inspecte the tenon substance from the insie. The gap between the native tenon stumps,25to 80 mmin length,was fille with scar tissue (Fig. 1). The mean length of the gap was 43.3 mm (Table I). Proximally, the tricepssuraewasreleasebybluntissection of the ahesion. The mile part of the scar tissue locate between the tenon stumps was resecte. After the resection, we confirme that the approximation of the proximal an istal ens of the tenon was possiblewiththeanklein20 to 30 of plantar flexion. If neee, the aitional scar tissue was resecte. The excise tissue was 15 to 50 mm in length. The mean length of the excise scar was 26.1 mm(table I).The repair was performe using Krackow sutures of no.-2 nonabsorbable polyfilament 32 in each tenon stump. The tenon stumps, with the interpose scar tissue, were then suture (Fig. 2), with the ankle in 20 to 30 of plantar flexion to match the uninvolve ankle. After completing the repair, the paratenon was suture, an the subcutaneous tissue an skin were close. Postoperative Treatment Postoperatively, patients wore a below-the-knee cast that hel the ankle in 20 of plantar flexion, an non-weight-bearing walking was continue for 2 weeks. At 3 weeks postoperatively, the cast was remove an an ankle-foot orthosis with 3 heel weges that hel the ankle in 20 of plantar flexion was applie. Partial weight-bearing walking an range-of-motion exercises were initiate. One heel wege was remove each week. Patients were encourage to bear weight on the involve limb as soon as they felt comfortable an to graually progress to full weight-bearing. At 6 weeks postoperatively, the orthosis was remove. Double-heel-rise exercises were allowe at 7 weeks. Sports activities were encourage at 4 to 5 months postoperatively. Statistical Analysis Differences between preoperative an final postoperative measurements were analyze using the Wilcoxon signe rank test. The Wilcoxon-Mann-Whitney test was use to compare the maximum calf circumference between the rupture an nonrupture sies at the time of the latest follow-up. Significance was efine as p < 0.05. Kappa statistics were use to analyze the interobserver reliability using SPSS, version 22.0 (IBM). Results Clinical Results At the time of the latest follow-up, none of the patients exhibite any ifficulty in walking or climbing stairs. Fig. 4-A Fig. 4-B Figs. 4-A an 4-B T2-weighte MR images of the tenons of a 63-year-ol man. Fig. 4-A Preoperative image showing tenon thinning an iffuse intrateninous high-signal alterations at 3 months after injury. Fig. 4-B Postoperative image showing fusiform-shape tenon thickening an homogeneous low-signal alterations at 6 months postoperatively.

1172 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG Twenty-eight patients were pain-free an 2 patients reporte occasional mil calf pain. All 14 athletes ha returne to their pre-injury level of sports participation. The 3 competitive athletes ha full return to sports (i.e., playe in a game at their pre-injury level) at 5 to 6 months postoperatively, an the 11 recreational athletes fully returne to sports by 12 months postoperatively. The mean plantar flexion angle of the involve ankle significantly increase postoperatively (p = 0.0049). The mean orsiflexion angle of the involve ankle significantly ecrease postoperatively (p = 0.009). The mean calf circumference of the involve leg significantly increase postoperatively (p = 0.0087). The mean ifference in circumference between the involve an uninvolve calves was significantly higher preoperatively than that at the time of the latest follow-up (p = 0.0135). At the most recent follow-up examination, all except 2 patients coul perform a single-limb heel rise. The mean AOFAS score was 82.8 points preoperatively an 98.1 points at the time of the most recent follow-up examination (Table II). The mean ATRS at the time of the latest follow-up was 92.0 points (range, 80 to 100 points). The only postoperative complication was elaye wounhealing in 1 case, which heale within 4 weeks postoperatively without antibiotic treatment. There were no cases of infection, eep-vein thrombosis, skin necrosis, or rerupture. Preoperative an Postoperative MRI The kappa value for the interobserver reliability of MRI was 0.83 for tenon contour an 0.90 for a signal change. Accoring to the system of Lanis an Koch 33, these values correspone to an almost perfect level of agreement. On preoperative T2-weighte images, fusiform-shape tenon thickening an iffuse intrateninous high-signal alterations in the tenons were seen in 22 patients (Fig. 3-A), but these patients ha homogeneous lowsignal alterations in the tenons on MRI at 6 months postoperatively (Fig. 3-B). Tenon thinning was seen in the remaining 8 patients. Diffuse intrateninous high-signal alterations were seen preoperatively in 6 of these 8 patients (Fig. 4-A), but fusiformshape tenon thickening an homogeneous low-signal alterations were seen in the tenons on MRI at 6 months postoperatively (Fig. 4-B). Homogeneous low-signal alterations in the tenons were seen in 2 patients (Fig. 5-A) preoperatively, but both fusiform-shape tenon thickening an homogeneous low-signal alterations were seen in the tenons on MRI at 6 months postoperatively (Fig. 5-B). Histologic Finings In all specimens, scar tissue locate between the tenon stumps consiste of ense an thick collagen fibers with vessels. Obvious egenerative changes, such as tenolipomatosis, mucoi Fig. 5-A Fig. 5-B Figs. 5-A an 5-B T2-weighte MR images of a 43-year-ol woman with chronic Achilles tenon rupture. Fig. 5-A Preoperative image showing tenon thinning an homogeneous low-signal alterations in the tenons (arrows). Fig. 5-B Postoperative image showing fusiform-shape tenon thickening an homogeneous low-signal alterations (arrows) at 6 months postoperatively. Note that the tenon thinning observe preoperatively was change to tenon thickening postoperatively.

1173 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG TABLE II AOFAS Score, Ankle Motion, an Calf Circumference Before the Surgical Proceure* At the Time of the Latest Follow-up* P Value AOFAS score (points) 82.8 ± 8.3 (51 to 97) 98.1 ± 3.9 (90 to 100) NA Ankle motion Plantar flexion (eg) 52.7 ± 5.5 (40 to 60) 55.2 ± 5.0 (45 to 60) 0.0049 Dorsiflexion (eg) 24.3 ± 7.4 (15 to 35) 20.8 ± 2.7 (15 to 30) 0.009 Calf circumference Size of involve calf (cm) 33.9 ± 3.5 (27 to 40.5) 34.4 ± 3.4 (27 to 39.5) 0.0087 Calf wasting (cm) 1.6 ± 1.0 (0.5 to 4) 1.2 ± 0.6 (0 to 2.5) 0.0135 *The values are given as the mean an stanar eviation, with the range in parentheses. NA = not applicable. egeneration, or vascular changes 34, were not observe in any specimen. In 9 patients, scar tissue between the tenon stumps containe ense collagen fibers running parallel along the tenon axis with rows of fibroblasts lying between the bunles of collagen. However, the bunles of collagen fibers were thinner, an more fibroblasts were seen, compare with the intact tenon (Fig. 6-A). In the remaining 21 specimens, the scar tissue containe ense collagen fibers with highly cellular fibrovascular material, but the fiber bunles were not oriente along the axis of the tenon (Fig. 6-B). In the 3 patients whose uration from injury to the time of the surgical proceure was <12 weeks, less ense an thinner collagen fibers not oriente along the axis of the tenon with highly cellular fibrovascular material were seen. Fig. 6 Figs. 6-A an 6-B Histology of the scar tissue between the tenon stumps (hematoxylin an eosin, 100). Fig. 6-A The 34-year-ol woman whose images are presente in Figure 3. The scar tissue contains ense collagen fibers running parallel along the tenon axis. The collagen network is longituinally oriente with rows of fibroblasts lying between the bunles of collagen. Fig. 6-B The 63-year-ol man whose images are presente in Figure 4. Histologic examination of the specimen showe interpose scar tissue compose of irregularly arrange collagen fibers with highly cellular fibrovascular tissue. Discussion Wouns can heal by primary union (first intention) or seconary union (secon intention); secon intention healing involves more extensive scarring an woun contraction 35.Repair by connective tissue eposition involves angiogenesis, migration an proliferation of fibroblasts, collagen synthesis, an connective tissue remoeling 35. After Achilles tenon rupture, Achilles tenon healing that occurs following immobilization with nonsurgical treatment correspons to secon intention healing. However, elaye or neglecte Achilles tenon ruptures o not progress to natural secon intention healing. During woun-healing, a granulating woun that is assiste in its healing by an operative proceure, is change from healing by secon intention to healing by thir intention 36. Similarly, in the present stuy, we performe elaye primary suturing for these elaye or neglecte Achilles tenon ruptures, creating healing by thir intention. We treate 30 consecutive patients with chronic Achilles tenon rupture using a irect repair proceure. The postoperative scores were 98.1 points for the AOFAS score an 92.0 points for the ATRS, both of which were greater than previously reporte scores for chronic Achilles tenon rupture, which range from 85 to 96.5 points for the AOFAS an 83 to 91 points for the ATRS 6,12,13,17-19,25. There were no cases of rerupture, an all 14 athletes ha returne to their pre-injury

1174 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG Fig. 7 Operative photograph showing irect repair in a patient with thin scar tissue interpose between the tenon stumps. level of sports participation. Thus, the clinical outcomes of our operative metho were at least comparable with previously reporte outcomes for chronic Achilles tenon rupture. Moreover, our technique was associate with a lower rate (3%) of postoperative complications than those previously reporte, which range from 4 to 45% 6,7,11,12,14,17,18,20. All except 2 patients coul perform a single-limb heel rise postoperatively. We think that shortening of the elongate scar tissue restore the length of the Achilles tenon. A few reports have been publishe on the histologic finings of scar tissue between tenon stumps in chronic Achilles tenon ruptures 25,26,28. Lee et al. 25 showe that the interpose scar tissue was compose of thick collagen fibers that ran in parallel along the tenon axis. In our stuy, interpose scar tissue containe ense collagen fibers with arteries, veins, an capillaries. In 9 patients, interpose tissue containe ense collagen fibers running parallel along the tenon axis. In the remaining 21 specimens, the scar tissue containe ense collagen fibers with highly cellular fibrovascular tissue not oriente along the axis of the tenon. Histologic finings have clearly inicate that the scar tissue has the capacity to form tenon-like tissue. In the present stuy, 27 patients were >12 weeks post-injury, so the interpose tissue in these patients showe the healing of the fairly mature tenon; however, the bunles of collagen fibers were thinner than the intact tenon. The histology results suggest that it is possible to use interpose healing tissue to repair chronic Achilles tenon rupture. Postoperative MRI finings inicate goo tenon healing of the reconstructe Achilles tenon in all patients. Preoperatively, thin elongate scar tissue was observe in 8 patients (Figs. 4-A an 5-A). Even in these cases, we performe irect repair using interpose scar tissue (Fig. 7), an postoperative MRI finings showe fusiform-shape tenon thickening an homogeneous low-signal alterations in the tenons (Figs. 4-B an 5-B). We think that resection of the mile part of the scar tissue le to the migration of the fibroblasts from the stumps. The proliferation of fibroblasts an neovascularization followe by fibrogenesis in the repaire tenon may have increase the tenon thickness an resulte in the fusiform shape observe postoperatively. Furthermore, tension on the suture site ue to early functional rehabilitation may have aligne the bunles of collagen fibers parallel to one another along the axis of the tenon, thus increasing its mechanical strength 27,37. We believe that our operative metho restore the length of the elongate scar an improve the tenon strength base on the postoperative tenon thickening an goo arrangement of the bunles of collagen fibers. This stuy ha some limitations. First, to our knowlege, the psychometric properties of the AOFAS scoring system, incluing its valiity an reliability, have never been examine. However, there is still value in comparing our results with those of other publishe stuies. Secon, we use the apanese version of the ATRS questionnaire. The valiity an reliability of the English an Turkish versions of the ATRS questionnaire have been emonstrate 30,31 ; however, the apanese version has not been valiate. In conclusion, shortening of the tissue between the 2 tenon ens that inclue healing scar an irect repair of healing tenon without allograft or autograft can be effective for the treatment of elaye or neglecte Achilles tenon rupture. n Toshito Yasua, MD 1 Hiroaki Shima, MD 1 Katsunori Mori, MD 1 Momoko Kizawa, MD 1 Masashi Neo, MD 1 1 Department of Orthopeic Surgery, Osaka Meical College, Osaka, apan E-mail aress for T. Yasua: ort028@osaka-me.ac.jp E-mail aress for H. Shima: ort125@osaka-me.ac.jp E-mail aress for K. Mori: ort166@osaka-me.ac.jp E-mail aress for M. Kizawa: ort211@osaka-me.ac.jp E-mail aress for M. Neo: neo@osaka-me.ac.jp References 1. Barnes M, Hary AE. Delaye reconstruction of the calcaneal tenon. Bone oint Surg Br. 1986 an;68(1):121-4. 2. Bosworth DM. Repair of efects in the teno Achillis. Bone oint Surg Am. 1956 an;38(1):111-4. 3. Bugg EI r, Boy BM. Repair of neglecte rupture or laceration of the Achilles tenon. Clin Orthop Relat Res. 1968 an-feb;56:73-5. 4. Gabel S, Manoli A 2n. Neglecte rupture of the Achilles tenon. Foot Ankle Int. 1994 Sep;15(9):512-7. 5. Kissel CG, Blacklige DK, Crowley DL. Repair of neglecte Achilles tenon ruptures proceure an functional results. Foot Ankle Surg. 1994 an-feb;33 (1):46-52. 6. Lee DK. Achilles tenon repair with acellular tissue graft augmentation in neglecte ruptures. Foot Ankle Surg. 2007 Nov-Dec;46(6):451-5. 7. Lee YS, Lin CC, Chen CN, Chen SH, Liao WY, Huang CR. Reconstruction for neglecte Achilles tenon rupture: the moifie Bosworth technique. Orthopeics. 2005 ul;28(7):647-50.

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