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Gravity Equinus Position to Control the Tendon Length of Reversed Free Tendon Flap Reconstruction for Chronic Achilles Tendon Rupture
The Journal of Foot & Ankle Surgery 56 (2017) 37–41
Contents lists available at ScienceDirect
The Journal of Foot & Ankle Surgery journal homepage: www.jfas.org
Gravity Equinus Position to Control the Tendon Length of Reversed Free Tendon Flap Reconstruction for Chronic Achilles Tendon Rupture Takaki Sanada, MD, Eiji Uchiyama, MD Surgeon, Sports Orthopedics Surgery, Kanto Rosai Hospital, Kawasaki City, Japan
a r t i c l e i n f o
a b s t r a c t
Level of Clinical Evidence: 4
Repair of chronic Achilles tendon rupture is a surgical challenge. We describe the use of a free turndown tendon flap augmentation raised from the proximal gastrocnemius aponeurosis. To control optimal tension or the reconstructed Achilles tendon length, we used an original method by referring to the gravity planter flexion ankle angle of the contralateral limb. Key aspects of the technique are described. A retrospective analysis of the short-term outcomes achieved in a case series (n ¼ 56) is presented. The postoperative anthropometric findings are also presented to indicate the successful outcomes achieved with this technique. Ó 2016 by the American College of Foot and Ankle Surgeons. All rights reserved.
Keywords: gravity ankle angle length control turn down flap trauma
Acute Achilles tendon rupture tends to be misdiagnosed in approximately 20% of cases. Repair of a neglected tendon rupture is a surgical challenge (1). Even with timely treatment, 12% and 10% of all patients conservatively and surgically treated, respectively, will experience repeat rupture (2). A neglected ruptured Achilles tendon changes during the stage of chronic tendon impairment. In such cases, surgery is the first-choice treatment in the absence of any contraindication to surgery. In neglected tears, scar tissue fills the gap between the 2 original ruptured tendon ends, which results in an apparently elongated tendon (3). In contrast, repeat rupture after conservative treatment or after failed primary suture results in a gap owing to retraction of the torn tendon ends (4). A neglected Achilles tendon rupture results in marked gait impairment over time. Surgical treatment of chronic tendon rupture relies on bridging the gap or relengthening of the elongated tendons. Tendon transfer (5–7), a turndown flap (8–14), V-Y gastrocnemius fascial advancement (15), a free tendon graft (16,17), artificial material (18,19), and reconstruction of the interposed scar tissue (20,21) have been used to augment the gap. The wide variety of procedures itself reflects the challenge in the surgical repair of neglected Achilles tendon rupture. The key technical challenge in the repair of the chronically ruptured Achilles tendon is length or tension control. The ruptured tendon stump will lay buried in adhesive connective tissues. Moreover, the proximal and distal rupture stumps often cannot be approximated with a simple suture because of the retraction of both
stumps. In cases in which it is possible to approximate the stumps by maximal flexion at the ankle joint, a graft can be used to bridge over both ends. However, repair performed with the foot in maximal plantarflexion could lead to postoperative loss of ankle dorsiflexion. Conversely, avoidance of lack of ankle dorsiflexion after surgery may conduct to inadequate tension of the repaired tendon during the operation, so that it could mislead to impair functional recovery of the tendon. Therefore, intraoperative tendon length control is a key determinant of the outcomes of Achilles tendon repair. To determine the tendon length during surgery, we refer to the contralateral ankle angle with the patient in the prone position and under anesthesia. The use of this original tendon length control method has helped us to achieve good functional and anthropometric recovery with the use of a free Achilles tendon flap in patients with chronic Achilles tendon rupture. We have provided a new technique for the turn down flap by harvesting free tendon from the proximal gastrocnemius fascia. The turndown flap is a useful technique, because it allows the procedure to be accomplished with 1 local incision and precludes the sacrifice of a graft from another tendon. However, the original turn down flap reconstruction requires a longer skin incision to fashion the flap. A long incision increases the risk of wound complications owing to the relatively poor blood supply in this area (22). We report the shortterm clinical and functional outcomes achieved with our technique, which uses a relatively small skin incision (9,12). Case Series
Financial Disclosure: None reported. Conflict of Interest: None reported. Address correspondence to: Takaki Sanada, MD, Sports Orthopedics Surgery, Kanto Rosai Hospital, 1-1 Kizuki Sumiyoshi-cho, Nakahara-Ku, Kawasaki City, Kanagawa Prefecture 211-8510, Japan. E-mail address: [email protected] (T. Sanada).
Patients and Methods We performed a retrospective analysis of data from 56 patients treated at our institute from January 2005 to December 2012. The
1067-2516/$ - see front matter Ó 2016 by the American College of Foot and Ankle Surgeons. All rights reserved. http://dx.doi.org/10.1053/j.jfas.2016.09.007
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T. Sanada, E. Uchiyama / The Journal of Foot & Ankle Surgery 56 (2017) 37–41
mean age at surgery was 43 (range 14 to 77) years. The mean followup duration was 12 (range 6 to 36) months. Of the 56 patients, 18 had a neglected tear, 19 had repeat rupture after primary suture, and 19 had repeat rupture after conservative treatment. The patients included 1 professional soccer player, 1 professional ballet dancer, 1 softball national team member, 11 high-level sports athletes, 13 sustainable recreational sports athlete and 17 occasional recreational sportsmen. The other 12 patients did not usually take part in regular sports activities. The diagnosis was determined from the clinical and radiologic examinations. The average time from the initial injury to surgery was 19 (range 3 to 92) weeks and that from repeat rupture to surgery was 6 weeks (range 3 days to 32 weeks). Five patients had received corticosteroid injection therapy for Achilles tendinitis.
long was obtained in the present series. A slit was made at the center of the distal tendon. The proximal free gastrocnemius flap end was turned distally by 180 to allow its insertion into the slit of the distal Achilles tendon stump. The distal side of the turn down free flap was interposed between the proximal tendon ends. A 2- to 3-cm length overlap between the flap and the distal and proximal ends was maintained. Therefore, the length of free tendon flap required was 4 to 6 cm more than the gap between the ruptured tendon stumps. Between both ends of the tendon, the turn down free graft was fixed using side-to-side interrupted sutures (Fig. 2). After skin closure, a below-the-knee cast was applied with the foot in a gravity plantarflexion ankle position. Rehabilitation
Surgical Technique Surgery was performed with the patient was positioned prone and an air tourniquet inflated. An approximately 10- to 15-cm longitudinal skin incision was made on the medial border of the Achilles tendon. After release of the peritendinous adhesions, smooth, passive tendon slide was confirmed. In many neglected tears, extensive fibrous tissue had filled the space between the proximal and distal tendon stumps. The scar tissue was resected to shorten the distance. Two parallel no. 1 nonabsorbable braided Tsuge sutures (23) were fashioned on the medial and lateral edges of the tendon to shorten the gap. The gap control was determined from the contralateral foot position; the angle of plantarflexion of the uninjured limb was assessed with the patient under anesthesia before surgery, with patient placed in the prone position and the knee flexed at 90 (Fig. 1). Referring to this prone gravity ankle position in the uninjured extremity, we tightened the braid to render the plantarflexion angle approximately 10 greater than that of the contralateral extremity. Next, the mid-third free gastrocnemius tendon graft was harvested from the proximal Achilles tendon end. The length of free flap depended on the gap between the ruptured tendon stumps. An average of 1.0 cm wide and 5 to 12 cm
Fig. 1. Measurement of gravity ankle angle with patient in prone equinus position. Plantarflexion angle of the contralateral ankle was measured with the patient under anesthesia immediately before surgery. The tendon tension control during surgery should target 10 extra plantarflexion in the same position as measured using a sterilized goniometer.
During the rehabilitation period, a below-the-knee cast was placed with the ankle maintained in plantarflexion. Nonweightbearing walking was allowed using double crutches from the fourth postoperative day. On the fifth postoperative day, a heel was applied under the bottom of the slight plantarflexion cast, and early full weightbearing was initiated with use of a walking cast. After 2 weeks, the walking below-the-knee cast was removed and changed to a hinged ankle-foot orthosis, which served to limit the dorsiflexion angle. This dorsal angle limitation was gradually decreased until at 8 weeks postoperatively when the orthosis was removed. Ankle range of movement exercises were started immediately after the patients began wearing the orthosis, which helped control the ankle dorsiflexion angle. At 5 weeks, supervised full weightbearing walking without the orthosis was started in the
Fig. 2. Reversed free tendon flap reconstruction. Double Tsuge sutures were fashioned to control the total tendon length. The mid-third free gastrocnemius tendon graft was harvested from the proximal Achilles tendon end. The flap was turned upside down and fixed by side-to-side sutures to bridge the gap.
T. Sanada, E. Uchiyama / The Journal of Foot & Ankle Surgery 56 (2017) 37–41
2.0 Gravity toe height difference (cm）
rehabilitation room. At 6 weeks, double-leg heel-raising exercises were encouraged, and the orthosis was removed for indoor activities. At 8 weeks, the orthosis was completely removed during outdoor activities. Jogging was started at 10 weeks, as soon as the single-leg heel-raising movement was possible. Sports activities were allowed when the continuous single-leg heel-raise exercise was achieved 20 times. This rehabilitation program is fundamentally similar to that used after surgical suturing of an acute Achilles tendon tear (24).
Assessment
1.0
0.0
-1.0
-2.0
-3.0 1M
We measured the gravity first toe height difference distance with the patient in the prone position, the knee joint in 90 of knee flexion, and the ankle in a relaxed position at monthly intervals for the first 6 months after surgery (Fig. 3). At 1 month, the gravity toe height of the involved side was 0.3 cm less than that of the contralateral limb. The first toe height difference tended to increase until 3 months postoperatively (mean difference 1.2 cm). The first toe height had gradually approximated that of the contralateral normal side at 6 months (mean difference 0.5 mm). The postoperative ankle flexion angle was also monitored. At 1 month, the mean dorsal flexion angle was 11 less than that in the contralateral ankle. At 2 months, the angle loss was <5 . At 5 months, the angle loss was within 1, which had decreased further to a mean loss of 0.4 , indicating full range of motion. Thus, even after reconstructing the tendon at 10 greater plantarflexion, it did not affect dorsal flexion loss (Fig. 4). The difference in the calf circumference was the greatest at 1 month after surgery (average difference 2.9 cm). The difference gradually decreased with progression of rehabilitation (average difference at 6 months 1.3 cm; Fig. 5).
3M
4M
5M
6M
Achievements In the clinical evaluation, we assessed the heel raise movement in 54 patients; 2 patients were excluded because of repeat rupture (Fig. 6). The mean period to achieving the double-legged heel raise in 53 patients was 8.2 weeks. Only 1 sedentary 74-year-old female patient with a neglected tear could not raise her bilateral heels at 2 years postoperatively. A single-leg heel raise was not achieved in 4 patients (including the 74-year-old female). One patient was a 65-year-old sedentary female who had been treated for repeat rupture after a primary Achilles tendon suture at another institute. The other 2 patients developed a wound infection at 4 weeks after surgery and could not achieve the single-leg heel raise during the follow-up period. The average time for successful single-leg heel raise in the other 50 patients was 14.6 weeks. The average time required for the continuous 20-time single-leg heel raise was 21.5 weeks in 47 patients. The 7 patients who could not achieve the 20-time heel raise without repeat rupture included the 4 patients mentioned previously and 3 patients who did not have any history of involvement in active sports or had transient skin infections. The average age of the latter 3 patients was 64.9 years. Return to Active Sports A total of 14 high-level competitive athletes and 13 sustainable recreational sports players were included in the present series. Of the 27 patients, 25 (93%) could return to play at the same level of sports. Of the 14 patients involved in high-level competitive athletic activity, 13 were able to return to their previous sports level at an average of 7.2 (range 5 to 24) postoperatively. One patient who could not return to play at the previous sports level was a professional soccer player. He had undergone a total of 4 surgical operations; he finally retired from professional soccer and played at a recreational level. Of the 13 2.0 0.0 ）
Results
2M
Fig. 3. Gravity toe height difference at 1, 2, 3, 4, 5, and 6 months after Achilles tendon repair. Data expressed as the mean standard deviation.
-2.0 Dorsi flexion difference (
Anthropometric findings were assessed monthly for the first 6 months after surgery. For evaluation of the repaired tendons, first, the toe height difference in the gravity foot position was measured. This gravity toe height difference is the distance discrepancy between the first toe tips in a prone position with knee flexed at 90 and the calf muscles relaxed. An examiner gently holds both of the patient’s legs by placing their hands on the anterior edge of tibias to confirm relaxation of the calf muscles. The chronological side-to-side gravity toe height difference was recorded. The difference in the ankle dorsiflexion angle and calf circumference from that of the contralateral side was also measured with the patient in the supine position. Both knees were flexed to 90 and the heels were equally set on the examination table. Some patients occasionally skipped the monthly follow-up clinical appointments. The proportion of follow-up data collection ranged from a minimum of 71% at 1 month to a maximum of 91% at 2 months after surgery. The heel raise movement is a milestone for Achilles tendon functional recovery (24). We record the achievement time of the double-leg heel raise, single-leg heel raise, and 20-time continuous single-leg heel raise. We considered these heel raise functions to indicate the amount of recovery and to allow the patient to move forward in the rehabilitation process. For example, patients for whom the jogging exercise was allowed after accomplishment of a single-leg heel raise and the achievement of the continuous singleleg heel raise was considered the milestone necessary to achieve for a return to sporting activity. Postoperative complications were also recorded.
39
-4.0 -6.0 -8.0 -10.0 -12.0 -14.0 1M
2M
3M
4M
5M
6M
Fig. 4. Passive dorsiflexion angle difference at 1, 2, 3, 4, 5, and 6 months after Achilles tendon repair. Data expressed as the mean standard deviation.
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T. Sanada, E. Uchiyama / The Journal of Foot & Ankle Surgery 56 (2017) 37–41
Calf circumference difference (cm)
0.0
-1.0
-2.0
-3.0
-4.0
-5.0 1M
2M
3M
4M
5M
6M
Fig. 5. Calf circumference difference at 1, 2, 3, 4, 5, and 6 months after Achilles tendon repair. Data expressed as the mean standard deviation.
patients who were involved in sports at a recreational level, 12 were able to return to play after an average of 6.2 (range 4.5 to 9) months. One patient with repeat rupture at 7 weeks after our surgery could not quite return to play in the same sport. Complications Two patients (3.6%) developed repeat Achilles tendon rupture. One patient had received a corticosteroid injection before the reconstruction surgery and the other was a professional soccer player who might have undergone an aggressive overpaced rehabilitation. Both these patients underwent repeat reconstructive surgery using harvested autograft hamstring tendons. Deep infection occurred in 4 patients (7.1%). All 4 patients required treatment with additional debridement and antibiotic therapy. These infections occurred 4 to 8 weeks after surgery. Irrigation and debridement were performed in all patients; however, they recovered from the infection without resection of the free reversed tendon flap, and repeat reconstructive surgery was not required. They returned to play at their previous sport level 6 to 24 months after surgery. None of the patients developed deep venous thrombosis. Discussion The turn down flap procedure is a commonly practiced technique. Lindholm (12) reported a technique involving 2 flaps fashioned from 30.0 25.0
Weeks
20.0 15.0 10.0 5.0 0.0 Double-legged Heel Raise
Single-legged Heel Raise
20 mes Single-legged Heel Raise
Fig. 6. Time required to achieve double-leg heel raise, single-leg heel raise, and 20-time continuous single-leg heel raise. Data expressed as mean standard deviation. The 20time continuous single-leg heel raise is equivalent to manual muscle testing grade 5.
proximal gastrocnemius fascia to bridge the gap. Using this method, the required precise flap length cannot be measured before the flap is freed; thus, the flap might take longer to bridge the gap adequately. Also, the skin incision length increases in proportion to the flap length. The skin incision extended from the middle of the calf to the calcaneus in the study by Lindholm (12), upward of the tendinous raphe in the study by Bosworth (9), and from the calcaneus to the myotendinous junction in the study by Gerdes et al (14). In contrast, we estimated the minimum required length of the flap from the gap length when fashioning the double Tsuge suture in the gravity ankle position (23). Usually, our free flap length is 4 cm longer than the controlled gap length. By knowing that the necessary minimum length for the free flap taken from the proximal gastrocnemius fascia, we were able to minimize the length of the skin incision. Repair of chronic Achilles tendon tears is challenging, in particular, with respect to the control of the tendon length and attainment of the optimal tension during surgery. Achilles tendon elongation decreases the heel rise height (25). In contrast, too short a length of the Achilles tendon tends to restrict ankle dorsiflexion. Thus, the initial tendon length at surgery is the key to successful functional recovery. Our method for tendon length control includes setting the injured leg at 10 greater ankle plantarflexion compared with the contralateral ankle with the patient in the prone position. Although the initial tension is comparatively greater, from our observation of the gravity toe height difference, the tension tends to resolve within 3 months. However, the loosening tension then retightened, and the side-to-side gravity toe height difference diminished subsequently. The same phenomenon has been well reported with other operative and nonoperative treatment (26). Some reasons for the phenomenon of the temporally loosened tension that gradually tightened up again are conceivable. As a correlated phenomenon, we found that the difference in calf circumference decreased with the decrease in the discrepancy in toe height. These 2 observations suggest that muscle hypertrophy helps to regain the tendon–muscle unit tension. The calf circumference increase implies that the gastrocnemius and soleus muscles had undergone sequential hypertrophy after surgery, assisted by proper rehabilitation. The calf muscles are composed of bipennate muscle fibers with an oblique orientation then the penetrating angle increased in proportion to the calf muscle hypertrophy. We believe that the tendon was tract by hypertrophic bipennate muscle and sideto-side toe height difference was diminishing (27). The target Achilles tendon length or tension during surgery has been the subject of controversy. A general consensus has been reached in favor of maintaining plantarflexion at the time of tendon repair. However, the degree of plantarflexion reported previously has varied. In some reports, the precise extent of ankle flexion has not been reported. The various degrees of plantarflexion reported include 10 to 15 (5), 20 to 30 (20), and maximal plantarflexion (12,17). Others have used the degree of plantarflexion in the opposite limb as a reference, they set the ankle planterflexion degree in the same physiological equinus (16,21). An Achilles tendon elongation of 2 mm has been reported in the early mobilization group and 5 mm in the cast group at a mean duration of 60 weeks after surgery (26). In a comparison of tendon suture repair, the side-to-side tendon length difference was 2.6 cm (25). Thus, we believe that Achilles tendon repair should make the tendon somewhat shorter than that of the opposite side (28). Our method of tightening the tendon by 10 more than the equinus angle in the gravity ankle position has not been previously reported. We believe it is a reasonable intraoperative tendon length control method. In the present study, 4 patients experienced deep infection. All 4 patients required additional debridement surgery, although none
T. Sanada, E. Uchiyama / The Journal of Foot & Ankle Surgery 56 (2017) 37–41
required resection of the repaired tendon. All 4 patients achieved the 20-time continuous single leg heel raise at an average of 20 weeks after surgery. They were also able to return to the same previous highly demanding sports activity afterward, without Achilles tendon revision reconstruction surgery. In conclusion, our original tendon length control method resulted in a gravity toe height difference at 6 months after surgery without dorsiflexion loss, which enabled the patients to return to their previous level of sporting activity. However, further efforts are needed to reduce the infection and repeat rupture rates. Acknowledgments I appreciate Dr Eiji Uchiyama, co-author who invented this surgical procedure originally and gave me an opportunity to publish this article. His comments and suggestions were of inestimable value for this study. References 1. Jozsa L, Vist MK, Balint BJ, Reffy A, Jarwnen M, Letho M, Marzo M. The role of recreational sport activity in Achilles tendon rupture: clinical, pathoanatomical, and sociological study of 292 cases. Am J Sports Med 17:338–343, 1989. 2. Holm C, Kjaer M, Eliasson P. Achilles tendon rupturedtreatment and complications: a systematic review. Scand J Med Sci Sports 25:1–10, 2015. 3. Mendicino SS, Reed TS. Repair of neglected Achilles tendon ruptures with a triceps surae muscle tendon advancement. J Foot Ankle Surg 35:13–18, 1996. R, Faxe n E, Olsson N, Eriksson BI, 4. Nilsson-Helander K, Silbernagel KG, Thomee Karlsson J. Acute Achilles tendon rupture: a randomized, controlled study comparing surgical and nonsurgical treatments using validated outcome measures. Am J Sports Med 38:2186–2193, 2010. 5. Mann RA, Holmes GB Jr, Seale KS, Collins DN. Chronic rupture of the Achilles tendon: a new technique of repair. J Bone Joint Surg Am 73:214–219, 1991. 6. Wapner KL, Pavlock GS, Hecht PJ, Naselli F, Walther R. Repair of chronic Achilles tendon rupture with flexor hallucis longus tendon transfer. Foot Ankle 14:443– 449, 1993. 7. Wegrzyn J, Luciani JF, Philippot R, Brunet-Guedj E, Moyen B, Besse JL. Chronic Achilles tendon rupture reconstruction using a modified flexor hallucis longus transfer. Int Orthop 34:1187–1192, 2010. 8. Christensen I. Rupture of the Achilles tendon: analysis of 57 cases. Acta Chir Scand 106:50–60, 1953. 9. Bosworth DM. Repair of defects in the tendo Achilles. J Bone Joint Surg Am 38:111– 114, 1956.
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10. Mulier T, Pienaar H, Dereymaeker G, Reynders P, Broos P. The management of chronic Achilles tendon ruptures: gastrocnemius turn down flap with or without flexor hallucis longus transfer. Foot Ankle Surg 9:151–156, 2003. 11. Arner O, Lindholm A, Orell SR. Histologic changes in subcutaneous rupture of the Achilles tendon: a study of 74 cases. Acta Chir Scand 116:484–490, 1959. 12. Lindholm A. A new method of operation of subcutaneous rupture of the Achilles tendon. Acta Chir Scand 117:261–270, 1959. 13. Takao M, Ochi M, Naito K, Uchio Y, Matsusaki M, Oae K. Repair of neglected Achilles tendon rupture using gastrocnemius fascial flaps. Arch Orthop Trauma Surg 123:471–474, 2003. 14. Gerdes MH, Brown TD, Bell AL, Baker JA, Levson M, Layer S. A flap augmentation technique for Achilles tendon repair: postoperative strength and functional outcome. Clin Orthop Relat Res 280:241–246, 1992. 15. Abraham E, Pankovich AM. Neglected rupture of the Achilles tendon: treatment by V-Y tendinous flap. J Bone Joint Surg Am 57:253–255, 1975. 16. Maffulli N, Leadbetter WB. Free gracilis tendon graft in neglected tears of the Achilles tendon. Clin J Sport Med 15:56–61, 2005. 17. Maffulli N, Buono AD, 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 41:865–871, 2013. 18. Ibrahim SAR. Surgical treatment of chronic Achilles tendon rupture. J Foot Ankle Surg 48:340–346, 2009. 19. Ozaki J, Fujiki J, Sugimoto K, Tamai S, Masuhara K. Reconstruction of neglected Achilles tendon rupture with Marlex mesh. Clin Orthop Relat Res 238:204–208, 1989. 20. Yasuda T, Kinoshita M, Okuda R. Reconstruction of chronic Achilles tendon rupture with the use of interposed tissue between the stumps. Am J Sports Med 35:582– 588, 2007. Y. Treatment of chronic 21. Khiami F, Di Schino M, Sariali E, Cao D, Rolland E, Catonne Achilles tendon rupture by shortening suture and free sural triceps aponeurosis graft. Orthop Traumatol Surg Res 99:585–591, 2013. 22. Maffulli N. Rupture of the Achilles tendon. J Bone Joint Surg Am 81:1019–1036, 1999. 23. Tsuge K, Ikuta Y, Matsuishi Y. Intra-tendinous tendon suture in the hand: a new technique. Hand 7:250–255, 1975. 24. Uchiyama E, Nomura A, Takeda Y, Hiranuma K, Iwaso H. A modified operation for Achilles tendon ruptures. Am J Sports Med 35:1739–1743, 2007. 25. Silbernagel KG, Stele R, Manal K. Deficits in heel-rise height and Achilles tendon elongation occur in patients recovering from an Achilles tendon rupture. Am J Sports Med 40:1564–1571, 2012. 26. Kangas J, Pajala Ari, Ohtonen P, Leppilahti J. Achilles tendon elongation after rupture repair: a randomized comparison of 2 postoperative regimens. Am J Sports Med 5:59–64, 2007. 27. Per A, Jesper LA, Poul D, Anne-Mette L, Aase W, Magnusson SP, HalkjærKristensen J, Erik B, Simonsen EB. A mechanism for increased contractile strength of human pennate muscle in response to strength training: changes in muscle architecture. J Physiol 534:613–623, 2001. 28. Coombs RRH, Klenerman L, Narcisi P, Nichols A, Pope FM. Collagen typing in Achilles tendon rupture. In Proceedings of the British Orthopaedic Research Society. J Bone Joint Surg Br 62:258, 1980.
Contents lists available at ScienceDirect
The Journal of Foot & Ankle Surgery journal homepage: www.jfas.org
Gravity Equinus Position to Control the Tendon Length of Reversed Free Tendon Flap Reconstruction for Chronic Achilles Tendon Rupture Takaki Sanada, MD, Eiji Uchiyama, MD Surgeon, Sports Orthopedics Surgery, Kanto Rosai Hospital, Kawasaki City, Japan
a r t i c l e i n f o
a b s t r a c t
Level of Clinical Evidence: 4
Repair of chronic Achilles tendon rupture is a surgical challenge. We describe the use of a free turndown tendon flap augmentation raised from the proximal gastrocnemius aponeurosis. To control optimal tension or the reconstructed Achilles tendon length, we used an original method by referring to the gravity planter flexion ankle angle of the contralateral limb. Key aspects of the technique are described. A retrospective analysis of the short-term outcomes achieved in a case series (n ¼ 56) is presented. The postoperative anthropometric findings are also presented to indicate the successful outcomes achieved with this technique. Ó 2016 by the American College of Foot and Ankle Surgeons. All rights reserved.
Keywords: gravity ankle angle length control turn down flap trauma
Acute Achilles tendon rupture tends to be misdiagnosed in approximately 20% of cases. Repair of a neglected tendon rupture is a surgical challenge (1). Even with timely treatment, 12% and 10% of all patients conservatively and surgically treated, respectively, will experience repeat rupture (2). A neglected ruptured Achilles tendon changes during the stage of chronic tendon impairment. In such cases, surgery is the first-choice treatment in the absence of any contraindication to surgery. In neglected tears, scar tissue fills the gap between the 2 original ruptured tendon ends, which results in an apparently elongated tendon (3). In contrast, repeat rupture after conservative treatment or after failed primary suture results in a gap owing to retraction of the torn tendon ends (4). A neglected Achilles tendon rupture results in marked gait impairment over time. Surgical treatment of chronic tendon rupture relies on bridging the gap or relengthening of the elongated tendons. Tendon transfer (5–7), a turndown flap (8–14), V-Y gastrocnemius fascial advancement (15), a free tendon graft (16,17), artificial material (18,19), and reconstruction of the interposed scar tissue (20,21) have been used to augment the gap. The wide variety of procedures itself reflects the challenge in the surgical repair of neglected Achilles tendon rupture. The key technical challenge in the repair of the chronically ruptured Achilles tendon is length or tension control. The ruptured tendon stump will lay buried in adhesive connective tissues. Moreover, the proximal and distal rupture stumps often cannot be approximated with a simple suture because of the retraction of both
stumps. In cases in which it is possible to approximate the stumps by maximal flexion at the ankle joint, a graft can be used to bridge over both ends. However, repair performed with the foot in maximal plantarflexion could lead to postoperative loss of ankle dorsiflexion. Conversely, avoidance of lack of ankle dorsiflexion after surgery may conduct to inadequate tension of the repaired tendon during the operation, so that it could mislead to impair functional recovery of the tendon. Therefore, intraoperative tendon length control is a key determinant of the outcomes of Achilles tendon repair. To determine the tendon length during surgery, we refer to the contralateral ankle angle with the patient in the prone position and under anesthesia. The use of this original tendon length control method has helped us to achieve good functional and anthropometric recovery with the use of a free Achilles tendon flap in patients with chronic Achilles tendon rupture. We have provided a new technique for the turn down flap by harvesting free tendon from the proximal gastrocnemius fascia. The turndown flap is a useful technique, because it allows the procedure to be accomplished with 1 local incision and precludes the sacrifice of a graft from another tendon. However, the original turn down flap reconstruction requires a longer skin incision to fashion the flap. A long incision increases the risk of wound complications owing to the relatively poor blood supply in this area (22). We report the shortterm clinical and functional outcomes achieved with our technique, which uses a relatively small skin incision (9,12). Case Series
Financial Disclosure: None reported. Conflict of Interest: None reported. Address correspondence to: Takaki Sanada, MD, Sports Orthopedics Surgery, Kanto Rosai Hospital, 1-1 Kizuki Sumiyoshi-cho, Nakahara-Ku, Kawasaki City, Kanagawa Prefecture 211-8510, Japan. E-mail address: [email protected] (T. Sanada).
Patients and Methods We performed a retrospective analysis of data from 56 patients treated at our institute from January 2005 to December 2012. The
1067-2516/$ - see front matter Ó 2016 by the American College of Foot and Ankle Surgeons. All rights reserved. http://dx.doi.org/10.1053/j.jfas.2016.09.007
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T. Sanada, E. Uchiyama / The Journal of Foot & Ankle Surgery 56 (2017) 37–41
mean age at surgery was 43 (range 14 to 77) years. The mean followup duration was 12 (range 6 to 36) months. Of the 56 patients, 18 had a neglected tear, 19 had repeat rupture after primary suture, and 19 had repeat rupture after conservative treatment. The patients included 1 professional soccer player, 1 professional ballet dancer, 1 softball national team member, 11 high-level sports athletes, 13 sustainable recreational sports athlete and 17 occasional recreational sportsmen. The other 12 patients did not usually take part in regular sports activities. The diagnosis was determined from the clinical and radiologic examinations. The average time from the initial injury to surgery was 19 (range 3 to 92) weeks and that from repeat rupture to surgery was 6 weeks (range 3 days to 32 weeks). Five patients had received corticosteroid injection therapy for Achilles tendinitis.
long was obtained in the present series. A slit was made at the center of the distal tendon. The proximal free gastrocnemius flap end was turned distally by 180 to allow its insertion into the slit of the distal Achilles tendon stump. The distal side of the turn down free flap was interposed between the proximal tendon ends. A 2- to 3-cm length overlap between the flap and the distal and proximal ends was maintained. Therefore, the length of free tendon flap required was 4 to 6 cm more than the gap between the ruptured tendon stumps. Between both ends of the tendon, the turn down free graft was fixed using side-to-side interrupted sutures (Fig. 2). After skin closure, a below-the-knee cast was applied with the foot in a gravity plantarflexion ankle position. Rehabilitation
Surgical Technique Surgery was performed with the patient was positioned prone and an air tourniquet inflated. An approximately 10- to 15-cm longitudinal skin incision was made on the medial border of the Achilles tendon. After release of the peritendinous adhesions, smooth, passive tendon slide was confirmed. In many neglected tears, extensive fibrous tissue had filled the space between the proximal and distal tendon stumps. The scar tissue was resected to shorten the distance. Two parallel no. 1 nonabsorbable braided Tsuge sutures (23) were fashioned on the medial and lateral edges of the tendon to shorten the gap. The gap control was determined from the contralateral foot position; the angle of plantarflexion of the uninjured limb was assessed with the patient under anesthesia before surgery, with patient placed in the prone position and the knee flexed at 90 (Fig. 1). Referring to this prone gravity ankle position in the uninjured extremity, we tightened the braid to render the plantarflexion angle approximately 10 greater than that of the contralateral extremity. Next, the mid-third free gastrocnemius tendon graft was harvested from the proximal Achilles tendon end. The length of free flap depended on the gap between the ruptured tendon stumps. An average of 1.0 cm wide and 5 to 12 cm
Fig. 1. Measurement of gravity ankle angle with patient in prone equinus position. Plantarflexion angle of the contralateral ankle was measured with the patient under anesthesia immediately before surgery. The tendon tension control during surgery should target 10 extra plantarflexion in the same position as measured using a sterilized goniometer.
During the rehabilitation period, a below-the-knee cast was placed with the ankle maintained in plantarflexion. Nonweightbearing walking was allowed using double crutches from the fourth postoperative day. On the fifth postoperative day, a heel was applied under the bottom of the slight plantarflexion cast, and early full weightbearing was initiated with use of a walking cast. After 2 weeks, the walking below-the-knee cast was removed and changed to a hinged ankle-foot orthosis, which served to limit the dorsiflexion angle. This dorsal angle limitation was gradually decreased until at 8 weeks postoperatively when the orthosis was removed. Ankle range of movement exercises were started immediately after the patients began wearing the orthosis, which helped control the ankle dorsiflexion angle. At 5 weeks, supervised full weightbearing walking without the orthosis was started in the
Fig. 2. Reversed free tendon flap reconstruction. Double Tsuge sutures were fashioned to control the total tendon length. The mid-third free gastrocnemius tendon graft was harvested from the proximal Achilles tendon end. The flap was turned upside down and fixed by side-to-side sutures to bridge the gap.
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2.0 Gravity toe height difference (cm）
rehabilitation room. At 6 weeks, double-leg heel-raising exercises were encouraged, and the orthosis was removed for indoor activities. At 8 weeks, the orthosis was completely removed during outdoor activities. Jogging was started at 10 weeks, as soon as the single-leg heel-raising movement was possible. Sports activities were allowed when the continuous single-leg heel-raise exercise was achieved 20 times. This rehabilitation program is fundamentally similar to that used after surgical suturing of an acute Achilles tendon tear (24).
Assessment
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We measured the gravity first toe height difference distance with the patient in the prone position, the knee joint in 90 of knee flexion, and the ankle in a relaxed position at monthly intervals for the first 6 months after surgery (Fig. 3). At 1 month, the gravity toe height of the involved side was 0.3 cm less than that of the contralateral limb. The first toe height difference tended to increase until 3 months postoperatively (mean difference 1.2 cm). The first toe height had gradually approximated that of the contralateral normal side at 6 months (mean difference 0.5 mm). The postoperative ankle flexion angle was also monitored. At 1 month, the mean dorsal flexion angle was 11 less than that in the contralateral ankle. At 2 months, the angle loss was <5 . At 5 months, the angle loss was within 1, which had decreased further to a mean loss of 0.4 , indicating full range of motion. Thus, even after reconstructing the tendon at 10 greater plantarflexion, it did not affect dorsal flexion loss (Fig. 4). The difference in the calf circumference was the greatest at 1 month after surgery (average difference 2.9 cm). The difference gradually decreased with progression of rehabilitation (average difference at 6 months 1.3 cm; Fig. 5).
3M
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Achievements In the clinical evaluation, we assessed the heel raise movement in 54 patients; 2 patients were excluded because of repeat rupture (Fig. 6). The mean period to achieving the double-legged heel raise in 53 patients was 8.2 weeks. Only 1 sedentary 74-year-old female patient with a neglected tear could not raise her bilateral heels at 2 years postoperatively. A single-leg heel raise was not achieved in 4 patients (including the 74-year-old female). One patient was a 65-year-old sedentary female who had been treated for repeat rupture after a primary Achilles tendon suture at another institute. The other 2 patients developed a wound infection at 4 weeks after surgery and could not achieve the single-leg heel raise during the follow-up period. The average time for successful single-leg heel raise in the other 50 patients was 14.6 weeks. The average time required for the continuous 20-time single-leg heel raise was 21.5 weeks in 47 patients. The 7 patients who could not achieve the 20-time heel raise without repeat rupture included the 4 patients mentioned previously and 3 patients who did not have any history of involvement in active sports or had transient skin infections. The average age of the latter 3 patients was 64.9 years. Return to Active Sports A total of 14 high-level competitive athletes and 13 sustainable recreational sports players were included in the present series. Of the 27 patients, 25 (93%) could return to play at the same level of sports. Of the 14 patients involved in high-level competitive athletic activity, 13 were able to return to their previous sports level at an average of 7.2 (range 5 to 24) postoperatively. One patient who could not return to play at the previous sports level was a professional soccer player. He had undergone a total of 4 surgical operations; he finally retired from professional soccer and played at a recreational level. Of the 13 2.0 0.0 ）
Results
2M
Fig. 3. Gravity toe height difference at 1, 2, 3, 4, 5, and 6 months after Achilles tendon repair. Data expressed as the mean standard deviation.
-2.0 Dorsi flexion difference (
Anthropometric findings were assessed monthly for the first 6 months after surgery. For evaluation of the repaired tendons, first, the toe height difference in the gravity foot position was measured. This gravity toe height difference is the distance discrepancy between the first toe tips in a prone position with knee flexed at 90 and the calf muscles relaxed. An examiner gently holds both of the patient’s legs by placing their hands on the anterior edge of tibias to confirm relaxation of the calf muscles. The chronological side-to-side gravity toe height difference was recorded. The difference in the ankle dorsiflexion angle and calf circumference from that of the contralateral side was also measured with the patient in the supine position. Both knees were flexed to 90 and the heels were equally set on the examination table. Some patients occasionally skipped the monthly follow-up clinical appointments. The proportion of follow-up data collection ranged from a minimum of 71% at 1 month to a maximum of 91% at 2 months after surgery. The heel raise movement is a milestone for Achilles tendon functional recovery (24). We record the achievement time of the double-leg heel raise, single-leg heel raise, and 20-time continuous single-leg heel raise. We considered these heel raise functions to indicate the amount of recovery and to allow the patient to move forward in the rehabilitation process. For example, patients for whom the jogging exercise was allowed after accomplishment of a single-leg heel raise and the achievement of the continuous singleleg heel raise was considered the milestone necessary to achieve for a return to sporting activity. Postoperative complications were also recorded.
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-4.0 -6.0 -8.0 -10.0 -12.0 -14.0 1M
2M
3M
4M
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Fig. 4. Passive dorsiflexion angle difference at 1, 2, 3, 4, 5, and 6 months after Achilles tendon repair. Data expressed as the mean standard deviation.
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T. Sanada, E. Uchiyama / The Journal of Foot & Ankle Surgery 56 (2017) 37–41
Calf circumference difference (cm)
0.0
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-4.0
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Fig. 5. Calf circumference difference at 1, 2, 3, 4, 5, and 6 months after Achilles tendon repair. Data expressed as the mean standard deviation.
patients who were involved in sports at a recreational level, 12 were able to return to play after an average of 6.2 (range 4.5 to 9) months. One patient with repeat rupture at 7 weeks after our surgery could not quite return to play in the same sport. Complications Two patients (3.6%) developed repeat Achilles tendon rupture. One patient had received a corticosteroid injection before the reconstruction surgery and the other was a professional soccer player who might have undergone an aggressive overpaced rehabilitation. Both these patients underwent repeat reconstructive surgery using harvested autograft hamstring tendons. Deep infection occurred in 4 patients (7.1%). All 4 patients required treatment with additional debridement and antibiotic therapy. These infections occurred 4 to 8 weeks after surgery. Irrigation and debridement were performed in all patients; however, they recovered from the infection without resection of the free reversed tendon flap, and repeat reconstructive surgery was not required. They returned to play at their previous sport level 6 to 24 months after surgery. None of the patients developed deep venous thrombosis. Discussion The turn down flap procedure is a commonly practiced technique. Lindholm (12) reported a technique involving 2 flaps fashioned from 30.0 25.0
Weeks
20.0 15.0 10.0 5.0 0.0 Double-legged Heel Raise
Single-legged Heel Raise
20 mes Single-legged Heel Raise
Fig. 6. Time required to achieve double-leg heel raise, single-leg heel raise, and 20-time continuous single-leg heel raise. Data expressed as mean standard deviation. The 20time continuous single-leg heel raise is equivalent to manual muscle testing grade 5.
proximal gastrocnemius fascia to bridge the gap. Using this method, the required precise flap length cannot be measured before the flap is freed; thus, the flap might take longer to bridge the gap adequately. Also, the skin incision length increases in proportion to the flap length. The skin incision extended from the middle of the calf to the calcaneus in the study by Lindholm (12), upward of the tendinous raphe in the study by Bosworth (9), and from the calcaneus to the myotendinous junction in the study by Gerdes et al (14). In contrast, we estimated the minimum required length of the flap from the gap length when fashioning the double Tsuge suture in the gravity ankle position (23). Usually, our free flap length is 4 cm longer than the controlled gap length. By knowing that the necessary minimum length for the free flap taken from the proximal gastrocnemius fascia, we were able to minimize the length of the skin incision. Repair of chronic Achilles tendon tears is challenging, in particular, with respect to the control of the tendon length and attainment of the optimal tension during surgery. Achilles tendon elongation decreases the heel rise height (25). In contrast, too short a length of the Achilles tendon tends to restrict ankle dorsiflexion. Thus, the initial tendon length at surgery is the key to successful functional recovery. Our method for tendon length control includes setting the injured leg at 10 greater ankle plantarflexion compared with the contralateral ankle with the patient in the prone position. Although the initial tension is comparatively greater, from our observation of the gravity toe height difference, the tension tends to resolve within 3 months. However, the loosening tension then retightened, and the side-to-side gravity toe height difference diminished subsequently. The same phenomenon has been well reported with other operative and nonoperative treatment (26). Some reasons for the phenomenon of the temporally loosened tension that gradually tightened up again are conceivable. As a correlated phenomenon, we found that the difference in calf circumference decreased with the decrease in the discrepancy in toe height. These 2 observations suggest that muscle hypertrophy helps to regain the tendon–muscle unit tension. The calf circumference increase implies that the gastrocnemius and soleus muscles had undergone sequential hypertrophy after surgery, assisted by proper rehabilitation. The calf muscles are composed of bipennate muscle fibers with an oblique orientation then the penetrating angle increased in proportion to the calf muscle hypertrophy. We believe that the tendon was tract by hypertrophic bipennate muscle and sideto-side toe height difference was diminishing (27). The target Achilles tendon length or tension during surgery has been the subject of controversy. A general consensus has been reached in favor of maintaining plantarflexion at the time of tendon repair. However, the degree of plantarflexion reported previously has varied. In some reports, the precise extent of ankle flexion has not been reported. The various degrees of plantarflexion reported include 10 to 15 (5), 20 to 30 (20), and maximal plantarflexion (12,17). Others have used the degree of plantarflexion in the opposite limb as a reference, they set the ankle planterflexion degree in the same physiological equinus (16,21). An Achilles tendon elongation of 2 mm has been reported in the early mobilization group and 5 mm in the cast group at a mean duration of 60 weeks after surgery (26). In a comparison of tendon suture repair, the side-to-side tendon length difference was 2.6 cm (25). Thus, we believe that Achilles tendon repair should make the tendon somewhat shorter than that of the opposite side (28). Our method of tightening the tendon by 10 more than the equinus angle in the gravity ankle position has not been previously reported. We believe it is a reasonable intraoperative tendon length control method. In the present study, 4 patients experienced deep infection. All 4 patients required additional debridement surgery, although none
T. Sanada, E. Uchiyama / The Journal of Foot & Ankle Surgery 56 (2017) 37–41
required resection of the repaired tendon. All 4 patients achieved the 20-time continuous single leg heel raise at an average of 20 weeks after surgery. They were also able to return to the same previous highly demanding sports activity afterward, without Achilles tendon revision reconstruction surgery. In conclusion, our original tendon length control method resulted in a gravity toe height difference at 6 months after surgery without dorsiflexion loss, which enabled the patients to return to their previous level of sporting activity. However, further efforts are needed to reduce the infection and repeat rupture rates. Acknowledgments I appreciate Dr Eiji Uchiyama, co-author who invented this surgical procedure originally and gave me an opportunity to publish this article. His comments and suggestions were of inestimable value for this study. References 1. Jozsa L, Vist MK, Balint BJ, Reffy A, Jarwnen M, Letho M, Marzo M. The role of recreational sport activity in Achilles tendon rupture: clinical, pathoanatomical, and sociological study of 292 cases. Am J Sports Med 17:338–343, 1989. 2. Holm C, Kjaer M, Eliasson P. Achilles tendon rupturedtreatment and complications: a systematic review. Scand J Med Sci Sports 25:1–10, 2015. 3. Mendicino SS, Reed TS. Repair of neglected Achilles tendon ruptures with a triceps surae muscle tendon advancement. J Foot Ankle Surg 35:13–18, 1996. R, Faxe n E, Olsson N, Eriksson BI, 4. Nilsson-Helander K, Silbernagel KG, Thomee Karlsson J. Acute Achilles tendon rupture: a randomized, controlled study comparing surgical and nonsurgical treatments using validated outcome measures. Am J Sports Med 38:2186–2193, 2010. 5. Mann RA, Holmes GB Jr, Seale KS, Collins DN. Chronic rupture of the Achilles tendon: a new technique of repair. J Bone Joint Surg Am 73:214–219, 1991. 6. Wapner KL, Pavlock GS, Hecht PJ, Naselli F, Walther R. Repair of chronic Achilles tendon rupture with flexor hallucis longus tendon transfer. Foot Ankle 14:443– 449, 1993. 7. Wegrzyn J, Luciani JF, Philippot R, Brunet-Guedj E, Moyen B, Besse JL. Chronic Achilles tendon rupture reconstruction using a modified flexor hallucis longus transfer. Int Orthop 34:1187–1192, 2010. 8. Christensen I. Rupture of the Achilles tendon: analysis of 57 cases. Acta Chir Scand 106:50–60, 1953. 9. Bosworth DM. Repair of defects in the tendo Achilles. J Bone Joint Surg Am 38:111– 114, 1956.
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