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Early post-operative results of neglected tendo-Achilles rupture reconstruction using short flexor hallucis longus tendon transfer: A prospective review
The Foot 22 (2012) 219–223
Contents lists available at SciVerse ScienceDirect
The Foot journal homepage: www.elsevier.com/locate/foot
Early post-operative results of neglected tendo-Achilles rupture reconstruction using short flexor hallucis longus tendon transfer: A prospective review Thomas F.M. Yeoman ∗ , Michael J.C. Brown, Anand Pillai Department of Trauma and Orthopaedics, Ninewells Hospital, Dundee, Scotland, United Kingdom
a r t i c l e
i n f o
Article history: Received 14 March 2012 Received in revised form 25 April 2012 Accepted 29 May 2012 Keywords: Achilles tendon rupture Tendo-Achilles rupture Tendon transfer Chronic rupture Neglected rupture Flexor hallucis longus transfer
a b s t r a c t Background: Various repair techniques have been reported for neglected tendo-Achilles rupture. Objective: This study aimed to prospectively investigate the impact of short flexor hallucis longus (FHL) transfer to the calcaneus for patients with neglected rupture secondary to trauma. Methods: One surgeon operated on a series of patients with neglected tendo-Achilles rupture. Ankle function and patient health were assessed pre and post-operatively using the American Orthopaedic Foot and Ankle Score (AOFAS) and the SF-36 score. Results: 11 patients (6 male; mean age 52.6) were included. Median time from injury to surgery was 13.3 weeks (range 6–104 weeks). The mean pre-operative AOFAS was 51.4 (range 26–87), 79.8 (range 64–94) at 3 months and 91.9 (range 77–100) at 6 months post-operatively. The mean pre-operative SF-36 score was 87.4 (range 75.4–109.5), 103.2 (range 74.1–115.4) at 3 months and 111.8 (range 103.9–116.2) at 6 months. All patients had improved SF-36 at 6 months. At 6 months 10 out 11 patients had resumed pre-injury daily activities. Conclusion: Direct transfer of FHL to the calcaneum with an interference screw allows correct tensioning and secure fixation. The procedure has low morbidity and reliable outcomes. The majority of patients were able to return to daily working activities with no restrictions. © 2012 Elsevier Ltd. All rights reserved.
1. Introduction The tendo-Achilles (TA) is one of the most commonly ruptured tendons, typically affecting those between 35 and 60 years [1]. Up to 27% of these injuries are initially misdiagnosed which may be related to both physicians and patients being misled by the inconsequential nature of the trauma reported, lack of pain and a retained ability to plantar flex the ankle [2,3]. Delayed treatment of this injury prohibits primary tendon repair and this occurs [4–6] weeks after the original rupture [5]. As a result neglected or chronic ruptures are challenging to treat and associated with worse post-operative outcomes compared to acute ruptures [6,7]. There is a general consensus amongst surgeons that neglected or chronic ruptures should be managed operatively excluding low-demand individuals or those where operative management is contraindicated [8–13]. Operative repair techniques for chronic TA ruptures include primary repair and/or augmentation with fascia advancement, local tendon transfer, free tissue transfer, synthetic grafts or allografts. Some techniques have been combined such as tissue advancement and tendon transfer [6].
Despite this there is no evidence-based guideline for deciding the type of operative management for neglected TA ruptures [8]. Several classification algorithms have been suggested for the treatment of neglected TA ruptures based upon the gap length between the retracted tendon ends but these recommendations are based upon expert opinion rather than comparative date. Therefore there currently there is a lack of evidence to support their implementation [7,8,14,15]. The use of flexor hallucis longus (FHL) to augment the TA was first described by Hansen in 1991 and has been used for patients with Achilles tendinosis and large rupture defects [16,17]. Few previous studies have prospectively investigated a series of patients that all ruptured their TA secondary to trauma and were subsequently managed with short FHL transfer. This study aimed to assess the early post-operative impact of short FHL transfer to the calcaneus for patients that presented with neglected TA rupture secondary to trauma. Pre and postoperative ankle function and general health were investigated using clinical and self-reported measures.
2. Methods ∗ Corresponding author. Tel.: +44 07742682396. E-mail addresses: [email protected], tomyeo [email protected] (T.F.M. Yeoman). 0958-2592/$ – see front matter © 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.foot.2012.05.004
This prospective study followed a consecutive series of patients that underwent short FHL transfer for neglected TA rupture
220
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Fig. 1. Posterior-medial incision and the paratenon was opened longitudinally to reveal the ruptured tendo-Achilles and retracted tendon ends.
between 2010 and 2011. All patients included in the study sustained a TA rupture secondary to trauma, that was initially misdiagnosed (neglected) and were subsequently operated on 4 weeks after the original injury. All patients consented to participation in the study and were diagnosed and operated on by the same consultant orthopaedic surgeon. Diagnosis was based on clinical findings and imaging elements including ultrasound scan and MRI. Common clinical findings included history of traumatic event, weakness with prolonged ambulation, difficulty climbing stairs (weak push-off), calcaneus gait, ankle swelling, calf wasting, palpable gap, increased passive dorsi-flexion of the ankle, weakness on repetitive or single leg heel-raise, and positive Thompson’s test [2,6,16]. All patients were followed from the pre-operative period through to 6 months post-operatively. Patients were assessed using reliable measures of foot and ankle function and general health. These measures were completed pre-operatively, 3 months postoperatively and 6 months post-operatively. Ankle and foot function was assessed using the American Orthopaedic Foot and Ankle Score (AOFAS), a nine element clinical rating system [18,19]. The patient’s general health was assessed using the SF-36 score. The SF-36 is a thirty-six-question health measure that combines both a physical component score (PCS) and a psychological component score (MCS). The measure has demonstrated significant reliability and validity [20,21]. Patients with a history of Achilles tendinosis, ipsilateral TA surgery or infection, regional cortisone injections, chronic fluroquinolone usage, chronic pain syndrome and systemic disease (including diabetes mellitus, seronegative inflammatory disease, spondyloarthropathies or sacoidosis) were excluded from this study [22,23]. All patients were operated on in the prone position under general anaesthetic. A thigh tourniquet was applied. A posteriormedial incision was made along the medial border of the TA, from the level of the musculo-tendinous junction to one inch below the TA insertion into the calcaneus [12]. The sural nerve was protected. The paratenon was opened longitudinally and the ends of the ruptured TA were exposed, see Fig. 1. Any evident interposing fibrosis between the retracted tendon ends was debrided back to healthy tendon [17]. Thickened and scarred paratenon was excised. Dissection was continued through to the deep fascia of the leg exposing the muscle belly of the FHL and its tendon. The FHL tendon was transected on the medial wall of the calcaneus with the ankle and hallux in plantar flexion to maximise the length of the harvested tendon, see Fig. 2. The posterior tibial nerve and artery were protected. Using the interference screw system and the guidance of a 5/32 Steinmann pin a drill hole was made through the posterior tuberosity into the calcaneus. The tendon was passed from superior
Fig. 2. The FHL tendon prepared for transfer after being transected on the medial wall of the calcaneus to maximise the length of the tendon from a single posterior incision.
to inferior through the calcaneus exiting through the plantar heel and the Steinmann pin was removed [17]. The interference screw was then inserted into the calcaneus capturing the FHL tendon, see Fig. 3. The wound was then washed out and closed. Post-operatively patients were kept in below knee plaster of Paris in full equinous for 4 weeks, then below knee plaster of Paris in semi-equinous for 2 weeks followed by 2 weeks in a weight bearing cast in neutral. Physiotherapy was started 8 weeks after the operation with range of movement and strengthening exercises. After 8 weeks patient had further protection for 4 weeks in an air boot cast. 3. Results This study included a total of 11 patients (6 male: 5 female), mean age 52.6 (age range 30–70 years). The left TA was ruptured in 7 patients and the right in 4. The median time from original injury to surgery was 13.3 weeks (mean 26.6 weeks, range 6–104 weeks). All TA ruptures were secondary to trauma. Mechanisms of injury included running, dancing, fall and direct impact. All patients had sustained complete ruptures and the mean gap between the retracted ends of the ruptured tendon was 5.8 cm (range 4–12 cm). Patients were immobilised postoperatively for 8 weeks and minimum follow up was 6 months, see Table 1. The mean pre-operative AOFAS was 51.4 (range 26–87), 79.8 (range 64–94) at 3 months and 91.9 (range 77–100) at 6 months
Fig. 3. Completed short FHL transfer to the calcaneus and screw fixation.
T.F.M. Yeoman et al. / The Foot 22 (2012) 219–223
221
100 80 Pre-operaon
60
3 months Post-operaon
40
6 months Post-operaon
Yes Yes Yes Yes No Yes Yes Yes Yes
20 Yes Yes
Resumed pre-injury daily activities at 6 months
120
0 MCS
6 6 6 6 6 6 6 6 6 6 Nil Infection Nil DVT Nil Nil Nil Nil Nil 89 100 100 100 81 92 91 88 93 91.9 79 84 31 28 29 52 50 48 51 51.4 12 72 16 14.5 104 12 20 6 12 26.6 47 51 53 60 34 30 70 61 52 52.6 3 4 5 6 7 8 9 10 11 Mean
L R L L L R R R L
6 12 5 4 6 5 4 5 4 5.8
8 8 8 8 8 8 8 8 8 8
94 73 64 87 71 80 72 77 88 79.8
6 6 Nil Nil 100 77 87 26 8 8 12 12 61 59 1 2
L L
6 7
Running Direct impact Dancing Dancing Dancing Fall Fall Fall Fall Running Running
87 85
6 months Post-op AOFAs 3 months Post-op AOFAS Pre-op AOFAS Immobilised (weeks) Activity at injury Gap (cm) Side Age
Injury to surgery (weeks)
PCS
Fig. 4. Mean pre-operative and post-operative outcome score results. AOFAS, American Orthopaedic Foot and Ankle Score, SF-36, short-form health survey; PCS, Physical Health Component of SF-36; MCS, psychological health component of SF36.
Patient
Table 1 Patient, injury and follow up information including foot and ankle function scores, complications and activity status at 6 months post-operation.
Complication
Out patient follow up (Months)
AOFAS Score Total SF-36
post-operatively, see Fig. 4. 9 out of 11 patients had an improved AOFAS at 3 months post-operatively. One patient showed the same score and one patient had a worse score at 3 months. All 11 patients had an improved AOFAS at 6 months compared to their pre-operative score. The mean pre-operative SF-36 score was 87.4 (range 75.4–109.5), 103.2 (range 74.1–115.4) at 3 months and 111.8 (range 103.9–116.2) at 6 months post-operatively. 10 out of 11 patients had an improved SF-36 at 3 months and all patients had an improved SF-36 at 6 months compared to their pre-operative score. All patients had an improved PCS and MCS at 6 months compared to their preoperative scores, see Fig. 4. Ankle pain scores improved from a mean of 2.8 (mild – moderate pain) pre-operatively to 1.8 (none – mild pain) at 3 months and 1.4 (none – mild pain) at 6 months post-operatively. At 6 months post-operatively 10 out 11 patients had resumed their pre-injury daily activities including work, walking, gardening and golf. Several patients had resumed more vigorous exercise such as hiking, cycling and gym work. One patient had not started playing tennis despite being able to walk up to 20 miles at 6 month. One patient who worked in the military had returned to light working duties at 6 months and resumed normal daily activities at 8 months. This patient had an improvement in his AOFAS from 29 pre-operatively to 81 at 6 months postoperatively. Post-operatively two patients developed complications. One patient had a superficial wound infection that was treated with washout and debridement and antibiotics. The patient subsequently progressed well with no further complications. One patient developed a DVT post-operatively and was readmitted and managed with anticoagulation therapy and subsequently improved. Despite the complications these two patients had maximal AOFAS scores at 6 months. There were no nerve injuries or re-ruptures recorded in these 11 patients with-in the follow up period. 4. Discussion Studies have demonstrated the benefit of several techniques for treating neglected TA rupture. Abraham and Prankovich proposed a TA advancement technique, V-Y alignment that allows end-to-end apposition of the ruptured tendon [24]. Their small study found 3 out of 4 patients achieved full strength at 9–15 months follow-up. Other small studies have also reported successful outcomes for this procedure. However Maffulli and Ajis suggest these studies are limited by both patient number and study design [8,25–27]. Mulier et al. investigated gastrocnemius turn down flaps with and without FHL tendon transfer. They found 50% of the patients reported a painful TA swelling at 6 months post-operatively that was still present in 20% of the patients at 1 year [9]. Poorer
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functional results and greater infection rates were seen by Mulier et al. compared to studies using tendon transfer techniques only [9,12,28,29]. Other studies have demonstrated better postoperative outcomes but it has been suggested that the quality of the proximal stump in neglected TA ruptures are often suboptimal for this technique [30–33]. In addition to the use of FHL various other tendon transfer techniques have been reported. Perez-Teuffer’s popularised the use of peronius brevis and Pintore et al.’s study showed good post-operative outcomes for this procedure [1,34]. However a concerning issue with the use of this tendon is the substitution of an evertor for a planter flexor that disrupt the normal muscle balance between the invertors and evertors [6]. The use of the flexor digitorum longus tendon transfer demonstrated good to excellent outcomes in 6 out of the 7 patients at an average follow up of 39 months in a study by Mann et al. [28]. Other alternatives to the procedures described above include free tissue transfers, allografts and synthetic grafts. The fascia lata transfer gave satisfactory post-operative results and no reports of complications from the donor site [35,36]. The gracilis was used in a study involving 21 patients at a mean of 28 months reported excellent and good results in 17 patients [33]. Allografts techniques have been reported but are limited by their expense and potential risk of disease transmission [6]. Several studies using synthetic have demonstrated successful results but there is concern regarding the use of a non-absorbable material in an area prone to breakdown and infection [33]. With regard to FHL transfers several studies have demonstrated good results for the treatment of chronic Achilles tendinopathy [37–40]. FHL transfer had been popularised because of the tendons durability and strength [12]. It is stronger than alternative tendons including peroneus brevis and FDL [41]. The muscle axis of contraction closely resembles that of the TA and its transfer to the calcaneus is thought to maintain normal muscle balance of the ankle, compared to alternative tendons [8]. A loss of push off strength has been documented in several studies and one study highlighted the significance of this loss in athletes [42]. Isokinetic results have shown reduced plantar flexion power but no functional disability was observed in these patients [43]. Wapner et al. reported functionally unimportant losses of ankle and hallux range of movement [12]. Hahn et al. also recognised the loss of active plantar flexion of the big toe but found patients were able to compensate well [44]. Several other studies all recognised some residual loss of plantar flexion strength but found no increased morbidity or levels of patient complaint and the majority of patients were highly satisfied with their foot and ankle function [37,39]. Despite not measuring loss of hallux interphalangeal strength our results demonstrate that 91% of the patients were able to regain sufficient foot and ankle function undoubtedly with a degree of compensation, as reported by Hahn, to enable their return to preinjury activities before 6 months [44]. Several FHL transfer techniques have been proposed. A short harvest used in our patients allows the FHL tendon to be harvested from a single posterior incision rather than through a second distal mid-foot incision. Den Hartog et al. demonstrated good to excellent results in patients with chronic tendinosis that underwent a single incision FHL transfer [14]. The benefit of the extra incision in the midfoot has been questioned and may be associated with increased morbidity, surgical time and risk of plantar nerve damage [9,45]. However the more distal harvest from the second incision does give extra tendon length that allows weaving of the tendon through the tendon stumps to facilitate repair [12]. The key finding of this study was that all patients showed an improved foot and ankle function at 6 months after the short FHL
transfer to the calcaneus with screw fixation for neglected TA rupture secondary to trauma. The mean improvement in foot and ankle function score was 40.5% and all but one patient had resumed pre-injury daily activities at 6 months. These results are comparable to the outcomes of previous similar studies [37,38]. One patient resumed pre-injury levels of daily activity at 8 months despite a 59% rise in the AOFAS at 6 months. This patient had the longest injury to operation interval, suggesting that a greater delay in operative treatment of neglected rupture may lead to slower recovery and a worse post-operative outcome. All patients demonstrated improvements in their physical and psychological health scores over the course of the study further demonstrating the benefit of the procedure to general health and well being. Our patient series had a major complication [DVT, re-rupture and deep infections) rate of 1/11 [9%] and a minor complication [seroma, haematoma and superficial wound infection) rate of 1/11 [9%]. These complication rates are lower than the majority of other similar studies as reported by Mulier et al.; major complication rates of 5–20% and minor complication rates of 10–30% [9]. The strength of this study was that it prospectively investigated a series of patients that sustained the same injury secondary to trauma and were managed with the same procedure by the same surgeon and all patients were followed up to 6 months. Its weaknesses included the small patient numbers and the lack of statistical analysis due to these numbers. In addition patients were only followed up to 6 months; further long-term outcomes would be beneficial. However by assessing early post-operative outcomes we were able to assess how soon patients were able to regain a pre-injury level of normal daily activity and quality of life. To our knowledge this is the only study that reports on a series of patient that all had short FHL transfer to the calcaneus with screw fixation for neglected TA ruptures secondary to trauma. This study demonstrates that direct transfer of FHL to the calcaneus with interference screw fixation provides low morbidity and reliable outcomes for patients that have sustained TA ruptures. The procedure facilitates a successful recovery of foot and ankle function, rapid return to pre-injury activity levels and improvement in patient quality of life. Conflict of interest The authors declare that they have no conflict of interest. References [1] Perez-Teuffer A. Traumatic rupture of the Achilles tendon Reconstruction by transplant and graft using the lateral peroneus brevis. Orthopedic Clinics of North America 1974;5:89–93. [2] Leslie H, Edwards W. Neglected ruptures of Achilles tendon. Foot and Ankle Clinics 2005;10:357–70. [3] Inglis AE, Scott WN, Sculco TP, Patterson AH. Ruptures of the tendo achillis. An objective assessment of surgical and non-surgical treatment. Journal of Bone and Joint Surgery 1976;58:990–3. [4] Maffulli N. Rupture of the Achilles tendon. Journal of Bone and Joint Surgery 1999;81(7):1019–36. [5] Gabel S, Manoli A. Foot fellow’s review: neglected rupture of the Achilles tendon. Foot and Ankle International 1994;15:512–7. [6] Padanilam TG. Chronic Achilles tendon ruptures. Foot and Ankle Clinics 2009;14(4):711–28. [7] Myerson MS. Achilles tendon ruptures. Instructional Course Lectures 1999;48:219–30. [8] Maffulli N, Ajis A. Management of chronic ruptures of the Achilles tendon. Journal of Bone and Joint Surgery 2008;90:1348–60. [9] 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 and Ankle Surgery 2003;9(3):151–6. [10] Kann JN, Myerson MS. Surgical management of chronic ruptures of the Achilles tendon. In: Myerson MS, Mandelbaum BR, editors. Foot and ankle clinics. 2nd ed. Philadelphia: WB Saunders; 1997. p. 535–45.
T.F.M. Yeoman et al. / The Foot 22 (2012) 219–223 [11] Leppilahti J, Orava S. Total Achilles tendon rupture. A review. Sports Medicine 1998;25(2):79–100. [12] Wapner KL, Pavlock GS, Hecht PJ, Naselli F, Walther R. Repair of chronic Achilles tendon rupture with flexor hallucis longus tendon transfer. Foot and Ankle 1993;14:443–9. [13] Jacobs D, Martens M, Van Audekercke RV, Mulier JC, Mulier F. Comparison of conservative and operative treatment of achilles tendon rupture. American Journal of Sports Medicine 1978;6:107. [14] Den Hartog B. Surgical strategies: delayed diagnosis or neglected Achilles’ tendon ruptures. Foot and Ankle International 2008;29:456–63. [15] Kuwada GT. Classification of tendo Achilles rupture with consideration of surgical repair techniques. Journal of Foot Surgery 1990;29:361–5. [16] Hansen S. Trauma to the heel cord. In: Jahss M, editor. Disorders of the foot and ankle: medical and surgical management. 2nd ed. Philadelphia: WB Saunders; 1991. p. 2355–60. [17] DeCarbo WT, Hyer CF. Interference screw fixation for flexor hallucis longus tendon transfer for chronic Achilles tendonopathy. Journal of Foot and Ankle Surgery 2008;47(1):69–72. [18] Button G, Pinney S. A meta-analysis of outcome rating scales in foot and ankle surgery: is there a valid, reliable, and responsive system? Foot and Ankle International 2004;25(8):521–5. [19] Kitaoka HB, Alexander IJ, Adelaar RS, Nunley JA, Myerson MS, Sanders M. Clinical rating systems for the ankle-hindfoot, midfoot, hallux, and lesser toes. Foot and Ankle International 1994;15(7):349–53. [20] Ware JE, Snow KK, Kosinski M, Gandek B. SF-36 Health Survey manual and interpretation guide. Boston: The Health Institute; 2003. [21] Garratt A, Schmidt L, Mackintosh A, Fitzpatrick R. Quality of life measurement: bibliographic study of patient assessed health outcome measures. British Medical Journal 2002;15, 324(7351):1417. [22] McGarvey W, Singh D, Trevino S. Partial Achilles tendon ruptures associated with fluoroquinolone antibiotics: a case report and literature review. Foot and Ankle International 1996;17:496–8. [23] Laseter JT, Russell JA. Anabolic steroid-induced tendon pathology: a review of the literature. Medicine and Science in Sports and Exercise 1991;23(1):1–3. [24] Abraham E, Pankovich AM. Neglected rupture of the Achilles tendon. Treatment by V-Y tendinous flap. Journal of Bone and Joint Surgery 1975;57:253–5. [25] Leitner A, Voigt C, Rahmanzadeh R. Treatment of extensive aseptic defects in old Achilles tendon ruptures: methods and case reports. Foot and Ankle 1992;13:176–80. [26] Kissel CG, Blacklidge DK, Crowley DL. Repair of neglected Achilles tendon ruptures—procedure and functional results. Journal of Foot and Ankle Surgery 1994;33(January–February (1)):46–52. [27] Parker RG, Repinecz M. Neglected rupture of the Achilles tendon. Treatment by modified Strayer gastrocnemius recession. Journal of the American Podiatry Association 1979;69:548–55.
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[28] Mann RA, Holmes Jr GB, Seale KS, Collins DN. Chronic rupture of the Achilles tendon: a new technique of repair. Journal of Bone and Joint Surgery 1991;73: 214–9. [29] Wapner KL, Hecht PJ, Mills Jr RH. Reconstruction of neglected Achilles tendon injury. Orthopedic Clinics of North America 1995;26(April (2)):249–63. Review. [30] Christensen I. Rupture of the Achilles tendon: analysis of 57 cases. Acta Chirurgica Scandinavica 1953;106:50–6. [31] Rush JH. Operative repair of neglected rupture of the tendo Achillis. Australian and New Zealand Journal of Surgery 1980;50:420–2. [32] Arner O, Lindholm A. Subcutaneous rupture of the Achilles tendon. A study of ninety two cases. Acta Chirurgica Scandinavica 1959;239:1–51. [33] Maffulli N, Leadbetter WB. Free gracilis tendon graft in neglected tears of the Achilles tendon. Clinical Journal of Sport Medicine 2005;15(2):56–61. [34] Pintore E, Barra V, Pintore R, Maffulli N. Peroneus brevis tendon transfer in neglected tears of the Achilles tendon. Journal of Trauma 2001;50:71–8. [35] Bugg Jr EI, Boyd BM. Repair of neglected rupture or laceration of the Achilles tendon. Clinical Orthopaedics and Related Research 1968;56:73–5. [36] Zadek I. Repair of old rupture of the tendo-Achilles by means of fascia. Report of a case. Journal of Bone and Joint Surgery 1940;22:1070–1. [37] Wilcox DK, Bohay DR, Anderson JG. Treatment of chronic achilles tendon disorders with flexor hallucis longus tendon transfer/augmentation. Foot and Ankle International 2000;21:1004–10. [38] 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. International Orthopaedics 2010;34(8):1187–92. [39] Dalal RB, Zenios M. The flexor hallucis longus tendon transfer for chronic tendoAchilles ruptures revisited. Annals of the Royal College of Surgeons of England 2003;85:283. [40] Coull R, Falvin R, Stephens MM. Flexor hallucis tendon transfer: evaluation of postoperative morbidity. Foot and Ankle International 2003;24: 931–4. [41] Silver RL, de la Garza J, Rang M. The myth of muscle balance. A study of relative strengths and excursions of normal muscles about the foot and ankle. Journal of Bone and Joint Surgery – British Volume 1985;67:432–7. [42] McClelland D, Maffulli N. Neglected rupture of the Achilles tendon: reconstruction with peroneus brevis tendon transfer. Surgeon 2004;2:209–13. [43] Frenette JP, Jackson DW. Lacerations of the flexor hallucis longus in the young athlete. Journal of Bone and Joint Surgery 1977;59:673–6. [44] Hahn F, Maiwald C, Horstmann T, Vienne P. Changes in plantar pressure distribution after Achilles tendon augmentation with flexor hallucis longus transfer. Clinical Biomechanics 2008;23(1):109–16. [45] Tashjian R, Hur J, Sullivan RJ, Campbell JT, DiGiovanni CW. Flexor hallucis longus transfer for repair of chronic Achilles tendinopathy. Foot and Ankle International 2003;24:673–6.
Contents lists available at SciVerse ScienceDirect
The Foot journal homepage: www.elsevier.com/locate/foot
Early post-operative results of neglected tendo-Achilles rupture reconstruction using short flexor hallucis longus tendon transfer: A prospective review Thomas F.M. Yeoman ∗ , Michael J.C. Brown, Anand Pillai Department of Trauma and Orthopaedics, Ninewells Hospital, Dundee, Scotland, United Kingdom
a r t i c l e
i n f o
Article history: Received 14 March 2012 Received in revised form 25 April 2012 Accepted 29 May 2012 Keywords: Achilles tendon rupture Tendo-Achilles rupture Tendon transfer Chronic rupture Neglected rupture Flexor hallucis longus transfer
a b s t r a c t Background: Various repair techniques have been reported for neglected tendo-Achilles rupture. Objective: This study aimed to prospectively investigate the impact of short flexor hallucis longus (FHL) transfer to the calcaneus for patients with neglected rupture secondary to trauma. Methods: One surgeon operated on a series of patients with neglected tendo-Achilles rupture. Ankle function and patient health were assessed pre and post-operatively using the American Orthopaedic Foot and Ankle Score (AOFAS) and the SF-36 score. Results: 11 patients (6 male; mean age 52.6) were included. Median time from injury to surgery was 13.3 weeks (range 6–104 weeks). The mean pre-operative AOFAS was 51.4 (range 26–87), 79.8 (range 64–94) at 3 months and 91.9 (range 77–100) at 6 months post-operatively. The mean pre-operative SF-36 score was 87.4 (range 75.4–109.5), 103.2 (range 74.1–115.4) at 3 months and 111.8 (range 103.9–116.2) at 6 months. All patients had improved SF-36 at 6 months. At 6 months 10 out 11 patients had resumed pre-injury daily activities. Conclusion: Direct transfer of FHL to the calcaneum with an interference screw allows correct tensioning and secure fixation. The procedure has low morbidity and reliable outcomes. The majority of patients were able to return to daily working activities with no restrictions. © 2012 Elsevier Ltd. All rights reserved.
1. Introduction The tendo-Achilles (TA) is one of the most commonly ruptured tendons, typically affecting those between 35 and 60 years [1]. Up to 27% of these injuries are initially misdiagnosed which may be related to both physicians and patients being misled by the inconsequential nature of the trauma reported, lack of pain and a retained ability to plantar flex the ankle [2,3]. Delayed treatment of this injury prohibits primary tendon repair and this occurs [4–6] weeks after the original rupture [5]. As a result neglected or chronic ruptures are challenging to treat and associated with worse post-operative outcomes compared to acute ruptures [6,7]. There is a general consensus amongst surgeons that neglected or chronic ruptures should be managed operatively excluding low-demand individuals or those where operative management is contraindicated [8–13]. Operative repair techniques for chronic TA ruptures include primary repair and/or augmentation with fascia advancement, local tendon transfer, free tissue transfer, synthetic grafts or allografts. Some techniques have been combined such as tissue advancement and tendon transfer [6].
Despite this there is no evidence-based guideline for deciding the type of operative management for neglected TA ruptures [8]. Several classification algorithms have been suggested for the treatment of neglected TA ruptures based upon the gap length between the retracted tendon ends but these recommendations are based upon expert opinion rather than comparative date. Therefore there currently there is a lack of evidence to support their implementation [7,8,14,15]. The use of flexor hallucis longus (FHL) to augment the TA was first described by Hansen in 1991 and has been used for patients with Achilles tendinosis and large rupture defects [16,17]. Few previous studies have prospectively investigated a series of patients that all ruptured their TA secondary to trauma and were subsequently managed with short FHL transfer. This study aimed to assess the early post-operative impact of short FHL transfer to the calcaneus for patients that presented with neglected TA rupture secondary to trauma. Pre and postoperative ankle function and general health were investigated using clinical and self-reported measures.
2. Methods ∗ Corresponding author. Tel.: +44 07742682396. E-mail addresses: [email protected], tomyeo [email protected] (T.F.M. Yeoman). 0958-2592/$ – see front matter © 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.foot.2012.05.004
This prospective study followed a consecutive series of patients that underwent short FHL transfer for neglected TA rupture
220
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Fig. 1. Posterior-medial incision and the paratenon was opened longitudinally to reveal the ruptured tendo-Achilles and retracted tendon ends.
between 2010 and 2011. All patients included in the study sustained a TA rupture secondary to trauma, that was initially misdiagnosed (neglected) and were subsequently operated on 4 weeks after the original injury. All patients consented to participation in the study and were diagnosed and operated on by the same consultant orthopaedic surgeon. Diagnosis was based on clinical findings and imaging elements including ultrasound scan and MRI. Common clinical findings included history of traumatic event, weakness with prolonged ambulation, difficulty climbing stairs (weak push-off), calcaneus gait, ankle swelling, calf wasting, palpable gap, increased passive dorsi-flexion of the ankle, weakness on repetitive or single leg heel-raise, and positive Thompson’s test [2,6,16]. All patients were followed from the pre-operative period through to 6 months post-operatively. Patients were assessed using reliable measures of foot and ankle function and general health. These measures were completed pre-operatively, 3 months postoperatively and 6 months post-operatively. Ankle and foot function was assessed using the American Orthopaedic Foot and Ankle Score (AOFAS), a nine element clinical rating system [18,19]. The patient’s general health was assessed using the SF-36 score. The SF-36 is a thirty-six-question health measure that combines both a physical component score (PCS) and a psychological component score (MCS). The measure has demonstrated significant reliability and validity [20,21]. Patients with a history of Achilles tendinosis, ipsilateral TA surgery or infection, regional cortisone injections, chronic fluroquinolone usage, chronic pain syndrome and systemic disease (including diabetes mellitus, seronegative inflammatory disease, spondyloarthropathies or sacoidosis) were excluded from this study [22,23]. All patients were operated on in the prone position under general anaesthetic. A thigh tourniquet was applied. A posteriormedial incision was made along the medial border of the TA, from the level of the musculo-tendinous junction to one inch below the TA insertion into the calcaneus [12]. The sural nerve was protected. The paratenon was opened longitudinally and the ends of the ruptured TA were exposed, see Fig. 1. Any evident interposing fibrosis between the retracted tendon ends was debrided back to healthy tendon [17]. Thickened and scarred paratenon was excised. Dissection was continued through to the deep fascia of the leg exposing the muscle belly of the FHL and its tendon. The FHL tendon was transected on the medial wall of the calcaneus with the ankle and hallux in plantar flexion to maximise the length of the harvested tendon, see Fig. 2. The posterior tibial nerve and artery were protected. Using the interference screw system and the guidance of a 5/32 Steinmann pin a drill hole was made through the posterior tuberosity into the calcaneus. The tendon was passed from superior
Fig. 2. The FHL tendon prepared for transfer after being transected on the medial wall of the calcaneus to maximise the length of the tendon from a single posterior incision.
to inferior through the calcaneus exiting through the plantar heel and the Steinmann pin was removed [17]. The interference screw was then inserted into the calcaneus capturing the FHL tendon, see Fig. 3. The wound was then washed out and closed. Post-operatively patients were kept in below knee plaster of Paris in full equinous for 4 weeks, then below knee plaster of Paris in semi-equinous for 2 weeks followed by 2 weeks in a weight bearing cast in neutral. Physiotherapy was started 8 weeks after the operation with range of movement and strengthening exercises. After 8 weeks patient had further protection for 4 weeks in an air boot cast. 3. Results This study included a total of 11 patients (6 male: 5 female), mean age 52.6 (age range 30–70 years). The left TA was ruptured in 7 patients and the right in 4. The median time from original injury to surgery was 13.3 weeks (mean 26.6 weeks, range 6–104 weeks). All TA ruptures were secondary to trauma. Mechanisms of injury included running, dancing, fall and direct impact. All patients had sustained complete ruptures and the mean gap between the retracted ends of the ruptured tendon was 5.8 cm (range 4–12 cm). Patients were immobilised postoperatively for 8 weeks and minimum follow up was 6 months, see Table 1. The mean pre-operative AOFAS was 51.4 (range 26–87), 79.8 (range 64–94) at 3 months and 91.9 (range 77–100) at 6 months
Fig. 3. Completed short FHL transfer to the calcaneus and screw fixation.
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221
100 80 Pre-operaon
60
3 months Post-operaon
40
6 months Post-operaon
Yes Yes Yes Yes No Yes Yes Yes Yes
20 Yes Yes
Resumed pre-injury daily activities at 6 months
120
0 MCS
6 6 6 6 6 6 6 6 6 6 Nil Infection Nil DVT Nil Nil Nil Nil Nil 89 100 100 100 81 92 91 88 93 91.9 79 84 31 28 29 52 50 48 51 51.4 12 72 16 14.5 104 12 20 6 12 26.6 47 51 53 60 34 30 70 61 52 52.6 3 4 5 6 7 8 9 10 11 Mean
L R L L L R R R L
6 12 5 4 6 5 4 5 4 5.8
8 8 8 8 8 8 8 8 8 8
94 73 64 87 71 80 72 77 88 79.8
6 6 Nil Nil 100 77 87 26 8 8 12 12 61 59 1 2
L L
6 7
Running Direct impact Dancing Dancing Dancing Fall Fall Fall Fall Running Running
87 85
6 months Post-op AOFAs 3 months Post-op AOFAS Pre-op AOFAS Immobilised (weeks) Activity at injury Gap (cm) Side Age
Injury to surgery (weeks)
PCS
Fig. 4. Mean pre-operative and post-operative outcome score results. AOFAS, American Orthopaedic Foot and Ankle Score, SF-36, short-form health survey; PCS, Physical Health Component of SF-36; MCS, psychological health component of SF36.
Patient
Table 1 Patient, injury and follow up information including foot and ankle function scores, complications and activity status at 6 months post-operation.
Complication
Out patient follow up (Months)
AOFAS Score Total SF-36
post-operatively, see Fig. 4. 9 out of 11 patients had an improved AOFAS at 3 months post-operatively. One patient showed the same score and one patient had a worse score at 3 months. All 11 patients had an improved AOFAS at 6 months compared to their pre-operative score. The mean pre-operative SF-36 score was 87.4 (range 75.4–109.5), 103.2 (range 74.1–115.4) at 3 months and 111.8 (range 103.9–116.2) at 6 months post-operatively. 10 out of 11 patients had an improved SF-36 at 3 months and all patients had an improved SF-36 at 6 months compared to their pre-operative score. All patients had an improved PCS and MCS at 6 months compared to their preoperative scores, see Fig. 4. Ankle pain scores improved from a mean of 2.8 (mild – moderate pain) pre-operatively to 1.8 (none – mild pain) at 3 months and 1.4 (none – mild pain) at 6 months post-operatively. At 6 months post-operatively 10 out 11 patients had resumed their pre-injury daily activities including work, walking, gardening and golf. Several patients had resumed more vigorous exercise such as hiking, cycling and gym work. One patient had not started playing tennis despite being able to walk up to 20 miles at 6 month. One patient who worked in the military had returned to light working duties at 6 months and resumed normal daily activities at 8 months. This patient had an improvement in his AOFAS from 29 pre-operatively to 81 at 6 months postoperatively. Post-operatively two patients developed complications. One patient had a superficial wound infection that was treated with washout and debridement and antibiotics. The patient subsequently progressed well with no further complications. One patient developed a DVT post-operatively and was readmitted and managed with anticoagulation therapy and subsequently improved. Despite the complications these two patients had maximal AOFAS scores at 6 months. There were no nerve injuries or re-ruptures recorded in these 11 patients with-in the follow up period. 4. Discussion Studies have demonstrated the benefit of several techniques for treating neglected TA rupture. Abraham and Prankovich proposed a TA advancement technique, V-Y alignment that allows end-to-end apposition of the ruptured tendon [24]. Their small study found 3 out of 4 patients achieved full strength at 9–15 months follow-up. Other small studies have also reported successful outcomes for this procedure. However Maffulli and Ajis suggest these studies are limited by both patient number and study design [8,25–27]. Mulier et al. investigated gastrocnemius turn down flaps with and without FHL tendon transfer. They found 50% of the patients reported a painful TA swelling at 6 months post-operatively that was still present in 20% of the patients at 1 year [9]. Poorer
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functional results and greater infection rates were seen by Mulier et al. compared to studies using tendon transfer techniques only [9,12,28,29]. Other studies have demonstrated better postoperative outcomes but it has been suggested that the quality of the proximal stump in neglected TA ruptures are often suboptimal for this technique [30–33]. In addition to the use of FHL various other tendon transfer techniques have been reported. Perez-Teuffer’s popularised the use of peronius brevis and Pintore et al.’s study showed good post-operative outcomes for this procedure [1,34]. However a concerning issue with the use of this tendon is the substitution of an evertor for a planter flexor that disrupt the normal muscle balance between the invertors and evertors [6]. The use of the flexor digitorum longus tendon transfer demonstrated good to excellent outcomes in 6 out of the 7 patients at an average follow up of 39 months in a study by Mann et al. [28]. Other alternatives to the procedures described above include free tissue transfers, allografts and synthetic grafts. The fascia lata transfer gave satisfactory post-operative results and no reports of complications from the donor site [35,36]. The gracilis was used in a study involving 21 patients at a mean of 28 months reported excellent and good results in 17 patients [33]. Allografts techniques have been reported but are limited by their expense and potential risk of disease transmission [6]. Several studies using synthetic have demonstrated successful results but there is concern regarding the use of a non-absorbable material in an area prone to breakdown and infection [33]. With regard to FHL transfers several studies have demonstrated good results for the treatment of chronic Achilles tendinopathy [37–40]. FHL transfer had been popularised because of the tendons durability and strength [12]. It is stronger than alternative tendons including peroneus brevis and FDL [41]. The muscle axis of contraction closely resembles that of the TA and its transfer to the calcaneus is thought to maintain normal muscle balance of the ankle, compared to alternative tendons [8]. A loss of push off strength has been documented in several studies and one study highlighted the significance of this loss in athletes [42]. Isokinetic results have shown reduced plantar flexion power but no functional disability was observed in these patients [43]. Wapner et al. reported functionally unimportant losses of ankle and hallux range of movement [12]. Hahn et al. also recognised the loss of active plantar flexion of the big toe but found patients were able to compensate well [44]. Several other studies all recognised some residual loss of plantar flexion strength but found no increased morbidity or levels of patient complaint and the majority of patients were highly satisfied with their foot and ankle function [37,39]. Despite not measuring loss of hallux interphalangeal strength our results demonstrate that 91% of the patients were able to regain sufficient foot and ankle function undoubtedly with a degree of compensation, as reported by Hahn, to enable their return to preinjury activities before 6 months [44]. Several FHL transfer techniques have been proposed. A short harvest used in our patients allows the FHL tendon to be harvested from a single posterior incision rather than through a second distal mid-foot incision. Den Hartog et al. demonstrated good to excellent results in patients with chronic tendinosis that underwent a single incision FHL transfer [14]. The benefit of the extra incision in the midfoot has been questioned and may be associated with increased morbidity, surgical time and risk of plantar nerve damage [9,45]. However the more distal harvest from the second incision does give extra tendon length that allows weaving of the tendon through the tendon stumps to facilitate repair [12]. The key finding of this study was that all patients showed an improved foot and ankle function at 6 months after the short FHL
transfer to the calcaneus with screw fixation for neglected TA rupture secondary to trauma. The mean improvement in foot and ankle function score was 40.5% and all but one patient had resumed pre-injury daily activities at 6 months. These results are comparable to the outcomes of previous similar studies [37,38]. One patient resumed pre-injury levels of daily activity at 8 months despite a 59% rise in the AOFAS at 6 months. This patient had the longest injury to operation interval, suggesting that a greater delay in operative treatment of neglected rupture may lead to slower recovery and a worse post-operative outcome. All patients demonstrated improvements in their physical and psychological health scores over the course of the study further demonstrating the benefit of the procedure to general health and well being. Our patient series had a major complication [DVT, re-rupture and deep infections) rate of 1/11 [9%] and a minor complication [seroma, haematoma and superficial wound infection) rate of 1/11 [9%]. These complication rates are lower than the majority of other similar studies as reported by Mulier et al.; major complication rates of 5–20% and minor complication rates of 10–30% [9]. The strength of this study was that it prospectively investigated a series of patients that sustained the same injury secondary to trauma and were managed with the same procedure by the same surgeon and all patients were followed up to 6 months. Its weaknesses included the small patient numbers and the lack of statistical analysis due to these numbers. In addition patients were only followed up to 6 months; further long-term outcomes would be beneficial. However by assessing early post-operative outcomes we were able to assess how soon patients were able to regain a pre-injury level of normal daily activity and quality of life. To our knowledge this is the only study that reports on a series of patient that all had short FHL transfer to the calcaneus with screw fixation for neglected TA ruptures secondary to trauma. This study demonstrates that direct transfer of FHL to the calcaneus with interference screw fixation provides low morbidity and reliable outcomes for patients that have sustained TA ruptures. The procedure facilitates a successful recovery of foot and ankle function, rapid return to pre-injury activity levels and improvement in patient quality of life. Conflict of interest The authors declare that they have no conflict of interest. References [1] Perez-Teuffer A. Traumatic rupture of the Achilles tendon Reconstruction by transplant and graft using the lateral peroneus brevis. Orthopedic Clinics of North America 1974;5:89–93. [2] Leslie H, Edwards W. Neglected ruptures of Achilles tendon. Foot and Ankle Clinics 2005;10:357–70. [3] Inglis AE, Scott WN, Sculco TP, Patterson AH. Ruptures of the tendo achillis. An objective assessment of surgical and non-surgical treatment. Journal of Bone and Joint Surgery 1976;58:990–3. [4] Maffulli N. Rupture of the Achilles tendon. Journal of Bone and Joint Surgery 1999;81(7):1019–36. [5] Gabel S, Manoli A. Foot fellow’s review: neglected rupture of the Achilles tendon. Foot and Ankle International 1994;15:512–7. [6] Padanilam TG. Chronic Achilles tendon ruptures. Foot and Ankle Clinics 2009;14(4):711–28. [7] Myerson MS. Achilles tendon ruptures. Instructional Course Lectures 1999;48:219–30. [8] Maffulli N, Ajis A. Management of chronic ruptures of the Achilles tendon. Journal of Bone and Joint Surgery 2008;90:1348–60. [9] 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 and Ankle Surgery 2003;9(3):151–6. [10] Kann JN, Myerson MS. Surgical management of chronic ruptures of the Achilles tendon. In: Myerson MS, Mandelbaum BR, editors. Foot and ankle clinics. 2nd ed. Philadelphia: WB Saunders; 1997. p. 535–45.
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