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Repair of chronic achilles tendon rupture with flexor hallucis longus tendon transfer
REPAIR OF CHRONIC ACHILLES TENDON RUPTURE WITH FLEXOR HALLUCIS LONGUS TENDON TRANSFER KEITH L. WAPNER, MD, and PAUL J. HECHT, MD
A technique is described for reconstruction of chronic Achilles tendon rupture using the flexor hallucis longus tendon. FoUow-up on seven patients (mean age 52 years) is provided (average follow-up 17 months, range 3 to 30 months). All patients were re-examined to assess postoperative range of motion, scar healing, and sensation. Motor strength was assessed by Cybex testing. Subjective satisfaction was examined by completion of a questionnaire. All patients had a satisfactory return to function. KEY WORDS: flexor hallucis Iongus, paratenon, tendon weaver
Chronic ruptures of the Achilles tendon are debilitating injuries that, in the past, have proven difficult to treat effectively. 1 Chronic tears of the t e n d o n result in lengthening of the tendon from progressive microtears and scarring, or a large fixed gap from complete rupture with secondary contraction and fibrosis of the gastrocsoleus complex after an inadequately diagnosed or treated acute rupture. These problems are more difficult to treat surgically than the acute tendon rupture. Although operative treatment of acute Achilles tendon ruptures remains controversial, 2'3 previous studies have clearly documented that operative treatment of chronic Achilles tendon ruptures provides a better functional outcome for the patient. 4's Multiple procedures have been described in the literature for reconstruction of chronic ruptures of the Achilles tendon. Most procedures involve bridging the gap with autologous or synthetic material. Use of autologous tissue, such as free plantaris tendon, 6 fascia lata, 7 and a turndown of proximal Achilles tendon tissue, s'9 have been well described. The use of synthetic materials, such as marlex mesh, 1~ dacron vascular graft, 11"~2 collagen tendon prosthesis, 13 polyglycol threads, ~4 and absorbable polymer carbon fiber, 6 have also been reported. Others have advocated augmenting the Achilles tendon with the flexor hallucis longus is or repairing chronic ruptures of the Achilles tendon with the transfer of muscles, such as the plantaris, 9 peroneous brevis, 16-1s and flexor digitorum longus. 19 We describe a n e w technique for reconstruction of chronic tears of the Achilles tendon using the flexor hallucis longus. 2~ Follow-up data are provided for the patients w h o have undergone this procedure to date. From the Division of Foot and Ankle Surgery, the Department of Orthopaedic Surgery, Thomas Jefferson University Hospital, Philadelphia, PA. Address reprint requests to Keith L. Wapner, MD, Foot and Ankle Service, Department of Orthopaedic Surgery, Thomas Jefferson University Hospital, 838 Walnut St, Philadelphia, PA 19107. Copyright 9 1994 by W. B. Saunders Company 1048-6666/94/0403-0002505.00/0
132
SURGICAL TECHNIQUE The procedure is performed with the patient in the supine position after induction of general or spinal anesthesia. A thigh tourniquet is applied. The foot and leg are prepared to the knee in the usual fashion and are then draped free into the sterile field. Attention is first directed to the medial border of the foot, where the flexor hallucis longus tendon is harvested. A longitudinal incision is made along the medial border of the midfoot, just above the level of the abductor muscle from the navicular to the head of the first metatarsal (Fig 1). The skin and subcutaneous tissues are sharply divided down to the level of the abductor hallucis fascia. The abductor is then reflected plantarward (Fig 2) and a small Weitlander retractor is placed in the wound. The flexor hallucis brevis is then reflected plantarward, exposing the deep midfoot anatomy. In some instances, it is necessary to release the origin of the short flexors to assist visualization. The flexor hallucis longus and flexor digitorum longus tendons are identified within the substance of the midfoot (Fig 3). They are generally covered by a layer of fatty tissue. Identification of the tendons is assisted by placing a finger over the lateral wall of the short flexor and manually plantar and dorsiflexing the first toe proximal interphalangeal (PIP) joint. The motion of the tendon can be felt, and dissection can be carried d o w n to identify the tendons of the flexor hallucis longus medially and the flexor digitorum longus just lateral (Fig 4). The flexor hallucis longus is divided as far distally as possible, but allowing an adequate distal stump to be transferred to the flexor digitorum longus. The proximal portion is tagged with a suture. The distal limb of the flexor hallucis longus is then sewn into the flexor digitorum longus (Fig 5), with all five toes in a neutral posture, thus providing flexion to all five toes via the flexor digitorum longus. A second longitudinal incision is made posteriorly along the medial aspect of the Achilles tendon, starting from the level of its musculotendinous junction and ex-
Operative Techniques in Orthopaedics, Vol 4, No 3 (July), 1994: pp 132-137
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Fig 1. Two incisions are used for the procedure. One incision is on the medial aspect of the midfoot and the second is along the anteromedial border of the Achilles tendon.
Fig 2. The midfoot incision has been carried down to identify the superior border of the abductor muscle. The dissection will be deepened along the interval between the undersurface of the first metatarsal and the abductor and the short flexors.
B II
Fig 3. (A) The flexor hallucis Iongus can be observed medially and the flexor digitorum is observed deeper in the wound laterally. The surrounding fat pad is observed. The plantar nerve lies plantar to the tendons in this fat pad. (B) (right) The relationship of the flexor digitorum Iongus and flexor hailucis Iongus is shown.
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Fig 4. The flexor hallucis is retracted, and the tag suture can be placed. It will be transected distal to the tag suture, and the distal stump will be sewn into the flexor digitorum Iongus. FLEXOR HALLUCIS LONGUS TENDON TRANSFER
133
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Fig 5. The anastomosis of the distal stump of the flexor hallucis Iongus to the flexor digitorum Iongus is performed while holding all five toes in a neutral posture,
tending to I inch below its insertion on the calcaneus (Fig 1). The incision is carried sharply down through subcutaneous tissue to the level of the Achilles paratenon. The paratenon is opened longitudinally, and the substance of the tendon is carefully inspected. Further dissection of the tendon is performed deep to the paratenon to allow full-thickness skin flaps and avoid skin slough. The fascia overlying the posterior compartment of the leg is then incised longitudinally, and the flexor hallucis longus is identified. The tendon is then retracted from the midfoot into the posterior incision (Fig 6). A transverse drill hole is placed just distal to the insertion of the Achilles tendon, halfway through the bone, from medial to lateral. A second vertical drill hole is made just deep to the insertion of the Achilles to meet the first hole (Fig 7). A large towel clip is used to augment the tunnel that is created (Fig 8). A suture passer is placed through the tunnel from distal to proximal. The
134
suture is then pulled through the tunnel, drawing the flexor hallucis longus tendon through the drill hole (Fig 9). The flexor hallucis longus is then woven from distal to proximal through the Achilles tendon using a tendon weaver (Fig 10). The tendon weaver is passed through the Achilles creating a tunnel in the tendon. The tag suture on the flexor hallucis is then grasped and pulled back through the tunnel, bringing the flexor tendon through the Achilles. This process is repeated to use the full length of tendon harvested (Fig 11). In complete ruptures of the Achilles, the flexor is used to bridge the gap, and tension is secured with the foot in 10~ of plantar flexion. The tendon is secured with multiple sutures of number 1 cottony Dacron (Deknatel, Fall River, MA). The completed reconstruction can be supplemented by various techniques if further strengthening is desired. In two patients in the original study group, the plantaris tendon was divided from its insertion and woven into the repair of the Achilles tendon and flexor hallucis longus for added strength. In another patient, a formal "turndown" procedure of the proximal Achilles tendon used in repair of acute Achilles tendon ruptures was performed. Using this technique, a central slip of the proximal segment of the Achilles tendon can be rotated inferiorly to any remaining distal stump of the Achilles tendon. 12 These augmentation procedures have currently been abandoned because the clinical outcomes were better in those patients who did not receive augmentation. 2~ After completion of the reconstruction, the paratenon is repaired. The subcutaneous tissue and skin are closed. Compressive dressings and plaster splints are applied to maintain 15~ of ankle plantar flexion. Before being discharged, the patient is placed in a short leg n o n weight-bearing cast at 15~ of equinus for 4 weeks. When the patient returns after 4 weeks, the dressing is removed and the forefoot is placed on a foot rest with the patient seated on an examining table. The hip is flexed and allowed to stay in this position until the foot reaches neutral (Fig 12). The foot is then placed into a short leg walking cast or removable cast walker with the ankle at neutral for an additional 4 weeks, and weight-bearing is begun. A rehabilitation program for strengthening and range of motion is begun 8 weeks postoperatively. The patient is maintained in a removable cast walker for community ambulation until 10~ of dorsiflexion is obtained, and grade 4/5 strength is achieved. At home, ambulation is allowed with a 7/16-in heel lift during this time. The patients are then advanced to regular shoe wear and treatment is continued with a home strengthening program with theraband (Hygenic Corp, Akron, OH). Athletic activity is restricted for 6 months after surgery.
RESULTS In the original study group, results were classified by criteria established by Mann. 19 Three patients had excellent results. These patients had no pain postoperatively, no limitation of activities, no postoperative w o u n d
WAPNER AND HECHT
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Fig 8, A large towel clip can be used to complete the tunnel for passage of the tendon through the bone. Fig 6. The flexor hallucis Iongus is retracted into the posterior wound.
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Fig 7. The two drill holes are placed in the posteromedial portion of the calcaneus.
FLEXOR HALLUCIS LONGUS TENDON TRANSFER
Fig 9. The flexor hallucis has been pulled through the tunnel in the calcaneus. The length of tendon available for weaving through the Achilles is shown.
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Fig 11. Schematic representation of the flexor hallucis Iongus tendon woven through the Achilles tendon.
Fig 10. The tendon weaver is used to pierce the Achilles and the tips are widened slightly to create a tunnel through which the flexor hallucis can be passed.
complications, excellent strength, and independent tiptoe stance. Three patients had good results. These patients had at least neutral dorsiflexion, no postoperative wound complications, and returned to their preoperative jobs and preinjury athletic activities; however, they all experienced some minor degree of pain, minor decrease in strength or motion, or small limitation in their level of activity compared with their preinjury standards. One patient (case 4) had a fair result, with global weakness in all muscle groups of the ankle. He required a molded foot-ankle orthosis for prolonged ambulation. Nonetheless, he had no postoperative wound complications, dorsiflexion to 10 ~ above neutral, and bilateral tiptoe stance. He returned to his job as a physician and to his preinjury level of golfing. The patient did have lumbar decompression surgery 4 months after his Achilles tendon repair, and it is unclear how much this complication interfered with his long-term result. There were no poor results. All patients returned to work. All six patients who were involved in recreational athletic activities preinjury returned to the same athletic activities postoperatively. There were no reruptures. Six of seven patients were able to walk without assistive devices. All patients regained at least neutral dorsiflexion and normal plantar flexion.
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Fig 12. The patient is seated on an examining table with the hip flexed and the forefoot resting on a foot rest. Gravity and the weight of the patient's leg are used to allow the leg to come to a neutral position, and then a removable cast boot is applied.
WAPNER AND HECHT
DISCUSSION
REFERENCES
A l t h o u g h m a n y p r o c e d u r e s h a v e b e e n described in the p a s t for r e c o n s t r u c t i o n of the chronic Achilles t e n d o n r u p t u r e , w e believe that this technique of reconstruction w i t h the flexor hallucis l o n g u s theoretically p r o v i d e s multiple a d v a n t a g e s o v e r the p r e v i o u s techniques described. First, the t e n d o n is long a n d durable, a n d its muscle is s t r o n g e r t h a n o t h e r t e n d o n t r a n s f e r s p r e v i o u s l y described. Silver 21 described the relative s t r e n g t h percentages of the m u s c l e s a r o u n d the foot a n d ankle. The gastroc-soleus c o m p l e x g e n e r a t e d a s t r e n g t h of 49.1%. H o w e v e r , the next s t r o n g e s t plantar flexor w a s n o t e d to be the flexor hallucis longus, w i t h a s t r e n g t h of 3.6%. The flexor d i g i t o r u m l o n g u s a n d p e r o n e u s brevis w e r e n o t e d to h a v e s t r e n g t h of 1.8% a n d 2.6%, respectively. Second, the axis of contractile force of the flexor hallucis longus m o s t closely r e p r o d u c e s that of the Achilles tendon. Third, the flexor hallucis l o n g u s fires in p h a s e with the gastroc-soleus muscle. Fourth, its a n a t o m i c proximity m a k e s the surgical technique easier a n d the n e e d to disturb the n e u r o v a s c u l a r b u n d l e or lateral c o m p a r t m e n t muscles is avoided. 22 H a r v e s t i n g the flexor hallucis longus in the m i d f o o t a d d s an additional 10 to 12 cm of t e n d o n length c o m p a r e d with the technique of H a n s e n . is This allows w e a v i n g of h a r v e s t e d t e n d o n t h r o u g h the Achilles as described b y M a n n , 19 b u t w i t h a s t r o n g e r m o t o r unit. This fifth a d v a n tage allows u s e of the a s s e t s of b o t h H a n s e n ' s a n d M a n n ' s techniques. Finally, transfer of the flexor hallucis longus m a i n t a i n s the n o r m a l muscle balance of the ankle by transferring a muscle of the s a m e original function (ie, plantar flexor to plantar flexor). Transfer of a muscle such as the p e r o n e u s brevis substitutes an evertor for a plantar flexor, resulting in a less functional repair b y t e n d o n transfer s t a n d a r d s a n d an u n k n o w n effect on the function of the foot a n d ankle b y partial loss of eversion strength. Analysis of the data also strongly s u g g e s t e d that functional o u t c o m e is strongly correlated w i t h patient effort a n d c o m p l i a n c e w i t h the p o s t o p e r a t i v e rehabilitation/ physical t h e r a p y . All patients w h o o b t a i n e d excellent functional results w e r e f o u n d to be highly c o m p l i a n t with the t h e r a p y prescribed, as d o c u m e n t e d b y b o t h the office record a n d the p a t i e n t ' s o w n report. T h o s e w i t h g o o d o u t c o m e s w e r e less consistently c o m p l i a n t w i t h the thera p y prescribed. The fair o u t c o m e (case 4), b y his o w n report, w a s not c o m p l i a n t w i t h the prescribed rehabilitation. In s u m m a r y , g o o d restoration of function can be obtained b y surgical t r e a t m e n t of chronic r u p t u r e s of the Achilles t e n d o n w i t h flexor hallucis longus t e n d o n recons t r u c t i o n . This a p p r o a c h p r o v i d e s a d v a n t a g e s o v e r techniques p r e v i o u s l y described in the literature, a n d the majority of patients can expect excellent or g o o d return of function after surgery.
1. Howard CB, Winston I, Bell W, et al: Late repair of the calcaneal tendon with carbon fiber. J Bone Joint Surg [Br] 66:206-208, 1984 2. Lead RB, Smith L: Non-surgical treatment of tendo achilles rupture. J Bone Joint Surg [Am] 54:1398-1407, 1972 3. Nistor L: Surgical and non-surgical treatment of Achilles tendon rupture. A prospective randomized study. J Bone Joint Surg [Am] 63:394-399, 1981 4. Carden DG, Noble J, Chalmers J, et al: Rupture of the calcaneal tendon. The early and late management. J Bone Joint Surg [Br] 69:416-419, 1987 5. Inglis AE, Scott WN, Sculco TP, et al: Ruptures of the tendo achilles. An objective assessment of surgical and non-surgical treatment. J Bone Joint Surg [Am] 58:990-993, 1976 6. Freilinger G, Scheuba G, Schurer-Waldheim H: Die Achillessehnenruptur und ihre naht mit hilfe der plantarissehne. Muschr Unf Heilk 73:523, 1970 (abstr) 7. Bugg El, Boyd BM: Repair of neglected rupture or laceration of the Achilles tendon. Clin Orthop 56:73-75, 1968 8. Bosworth DM: Repair of defects in the tendo achilles. J Bone Joint Surg [Am] 38:111-114, 1956 9. Lynn TA: Repair of the torn Achilles tendon, using the plantaris tendon as a reinforcing membrane. J Bone Joint Surg [Am] 48:268272, 1966 10. Ozaki J, Fujiki J, Sugimoto K, et al: Reconstruction of neglected Achilles tendon rupture with marlex mesh. Clin Orthop 238:204208, 1989 11. Levy M, Velkes S, Goldstein, et al: A method of repair for Achilles tendon ruptures without cast immobilization. Preliminary report. Clin Orthop 187:199-204, 1984 12. Lieberman JR, Lozman J, Czajka J, et al: Repair of Achilles tendon ruptures with dacron vascular graft. Clin Orthop 234:204-208, 1988 13. Kato YP, Dunn MG, Zawadsky JP, et al: Regeneration of Achilles tendon with a collagen tendon prosthesis. Results of a one-year implantation study. J Bone Joint Surg [Am] 73:561-574, 1991 14. Schedl R, Fasol P: Achilles tendon repair with the plantans tendon compared with repair using polyglycol threads. J Trauma 19:189194, 1979 15. Hansen, Sigvard T: Trauma to the heel cord, in Jahss MH (ed): Disorders of the Foot and Ankle (ed 2). Philadelphia, PA, Saunders, 1991, p 2357 16. Teuffer AP: Traumatic rupture of the Achilles tendon. Reconstruction by transplant and graft using the lateral peroneus brevis. Clin Orthop North Am 5:89-93, 1974 17. Turco VJ, Spinella AJ: Achilles tendon rupture-peroneus brevis transfer. Foot Ankle 7:253-259, 1987 18. Turco V, Spinella AJ: Team physician #2. Peroneus brevis transfer for Achilles tendon rupture in athletes. Orthop Rev 17:822-824, 1988 19. Mann RA, Holmes GB, Seale KS, et al: Chronic rupture of the Achilles tendon: A new technique of repair. J Bone Joint Surg [Am] 73: 214-219, 1991 20. Wapner KL, Pavlock GS, Hecht PJ, et al: Repair of chronic achilles tendon rupture with flexor hallucis longus tendon transfer. Foot Ankle 14(8):443-449, 1993 21. Silver RL, DeLa Garza J, Rang M: The myth of muscle balance. A study of relative strengths and excursions of normal muscles about the foot and ankle. J Bone Joint Surg [Br] 67:432-437, 1985 22. Wapner KL, Allardyce T, Shea J, et al: Anatomic basis for tendon selection in reconstruction of ruptures of the Achilles and posterior tiblal tendon. Presented at American Orthopaedic Foot and Ankle Society Summer Meeting, Napa, CA, July, 1992
FLEXOR HALLUCIS LONGUS TENDON TRANSFER
137
A technique is described for reconstruction of chronic Achilles tendon rupture using the flexor hallucis longus tendon. FoUow-up on seven patients (mean age 52 years) is provided (average follow-up 17 months, range 3 to 30 months). All patients were re-examined to assess postoperative range of motion, scar healing, and sensation. Motor strength was assessed by Cybex testing. Subjective satisfaction was examined by completion of a questionnaire. All patients had a satisfactory return to function. KEY WORDS: flexor hallucis Iongus, paratenon, tendon weaver
Chronic ruptures of the Achilles tendon are debilitating injuries that, in the past, have proven difficult to treat effectively. 1 Chronic tears of the t e n d o n result in lengthening of the tendon from progressive microtears and scarring, or a large fixed gap from complete rupture with secondary contraction and fibrosis of the gastrocsoleus complex after an inadequately diagnosed or treated acute rupture. These problems are more difficult to treat surgically than the acute tendon rupture. Although operative treatment of acute Achilles tendon ruptures remains controversial, 2'3 previous studies have clearly documented that operative treatment of chronic Achilles tendon ruptures provides a better functional outcome for the patient. 4's Multiple procedures have been described in the literature for reconstruction of chronic ruptures of the Achilles tendon. Most procedures involve bridging the gap with autologous or synthetic material. Use of autologous tissue, such as free plantaris tendon, 6 fascia lata, 7 and a turndown of proximal Achilles tendon tissue, s'9 have been well described. The use of synthetic materials, such as marlex mesh, 1~ dacron vascular graft, 11"~2 collagen tendon prosthesis, 13 polyglycol threads, ~4 and absorbable polymer carbon fiber, 6 have also been reported. Others have advocated augmenting the Achilles tendon with the flexor hallucis longus is or repairing chronic ruptures of the Achilles tendon with the transfer of muscles, such as the plantaris, 9 peroneous brevis, 16-1s and flexor digitorum longus. 19 We describe a n e w technique for reconstruction of chronic tears of the Achilles tendon using the flexor hallucis longus. 2~ Follow-up data are provided for the patients w h o have undergone this procedure to date. From the Division of Foot and Ankle Surgery, the Department of Orthopaedic Surgery, Thomas Jefferson University Hospital, Philadelphia, PA. Address reprint requests to Keith L. Wapner, MD, Foot and Ankle Service, Department of Orthopaedic Surgery, Thomas Jefferson University Hospital, 838 Walnut St, Philadelphia, PA 19107. Copyright 9 1994 by W. B. Saunders Company 1048-6666/94/0403-0002505.00/0
132
SURGICAL TECHNIQUE The procedure is performed with the patient in the supine position after induction of general or spinal anesthesia. A thigh tourniquet is applied. The foot and leg are prepared to the knee in the usual fashion and are then draped free into the sterile field. Attention is first directed to the medial border of the foot, where the flexor hallucis longus tendon is harvested. A longitudinal incision is made along the medial border of the midfoot, just above the level of the abductor muscle from the navicular to the head of the first metatarsal (Fig 1). The skin and subcutaneous tissues are sharply divided down to the level of the abductor hallucis fascia. The abductor is then reflected plantarward (Fig 2) and a small Weitlander retractor is placed in the wound. The flexor hallucis brevis is then reflected plantarward, exposing the deep midfoot anatomy. In some instances, it is necessary to release the origin of the short flexors to assist visualization. The flexor hallucis longus and flexor digitorum longus tendons are identified within the substance of the midfoot (Fig 3). They are generally covered by a layer of fatty tissue. Identification of the tendons is assisted by placing a finger over the lateral wall of the short flexor and manually plantar and dorsiflexing the first toe proximal interphalangeal (PIP) joint. The motion of the tendon can be felt, and dissection can be carried d o w n to identify the tendons of the flexor hallucis longus medially and the flexor digitorum longus just lateral (Fig 4). The flexor hallucis longus is divided as far distally as possible, but allowing an adequate distal stump to be transferred to the flexor digitorum longus. The proximal portion is tagged with a suture. The distal limb of the flexor hallucis longus is then sewn into the flexor digitorum longus (Fig 5), with all five toes in a neutral posture, thus providing flexion to all five toes via the flexor digitorum longus. A second longitudinal incision is made posteriorly along the medial aspect of the Achilles tendon, starting from the level of its musculotendinous junction and ex-
Operative Techniques in Orthopaedics, Vol 4, No 3 (July), 1994: pp 132-137
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Fig 1. Two incisions are used for the procedure. One incision is on the medial aspect of the midfoot and the second is along the anteromedial border of the Achilles tendon.
Fig 2. The midfoot incision has been carried down to identify the superior border of the abductor muscle. The dissection will be deepened along the interval between the undersurface of the first metatarsal and the abductor and the short flexors.
B II
Fig 3. (A) The flexor hallucis Iongus can be observed medially and the flexor digitorum is observed deeper in the wound laterally. The surrounding fat pad is observed. The plantar nerve lies plantar to the tendons in this fat pad. (B) (right) The relationship of the flexor digitorum Iongus and flexor hailucis Iongus is shown.
FHL
Fig 4. The flexor hallucis is retracted, and the tag suture can be placed. It will be transected distal to the tag suture, and the distal stump will be sewn into the flexor digitorum Iongus. FLEXOR HALLUCIS LONGUS TENDON TRANSFER
133
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Fig 5. The anastomosis of the distal stump of the flexor hallucis Iongus to the flexor digitorum Iongus is performed while holding all five toes in a neutral posture,
tending to I inch below its insertion on the calcaneus (Fig 1). The incision is carried sharply down through subcutaneous tissue to the level of the Achilles paratenon. The paratenon is opened longitudinally, and the substance of the tendon is carefully inspected. Further dissection of the tendon is performed deep to the paratenon to allow full-thickness skin flaps and avoid skin slough. The fascia overlying the posterior compartment of the leg is then incised longitudinally, and the flexor hallucis longus is identified. The tendon is then retracted from the midfoot into the posterior incision (Fig 6). A transverse drill hole is placed just distal to the insertion of the Achilles tendon, halfway through the bone, from medial to lateral. A second vertical drill hole is made just deep to the insertion of the Achilles to meet the first hole (Fig 7). A large towel clip is used to augment the tunnel that is created (Fig 8). A suture passer is placed through the tunnel from distal to proximal. The
134
suture is then pulled through the tunnel, drawing the flexor hallucis longus tendon through the drill hole (Fig 9). The flexor hallucis longus is then woven from distal to proximal through the Achilles tendon using a tendon weaver (Fig 10). The tendon weaver is passed through the Achilles creating a tunnel in the tendon. The tag suture on the flexor hallucis is then grasped and pulled back through the tunnel, bringing the flexor tendon through the Achilles. This process is repeated to use the full length of tendon harvested (Fig 11). In complete ruptures of the Achilles, the flexor is used to bridge the gap, and tension is secured with the foot in 10~ of plantar flexion. The tendon is secured with multiple sutures of number 1 cottony Dacron (Deknatel, Fall River, MA). The completed reconstruction can be supplemented by various techniques if further strengthening is desired. In two patients in the original study group, the plantaris tendon was divided from its insertion and woven into the repair of the Achilles tendon and flexor hallucis longus for added strength. In another patient, a formal "turndown" procedure of the proximal Achilles tendon used in repair of acute Achilles tendon ruptures was performed. Using this technique, a central slip of the proximal segment of the Achilles tendon can be rotated inferiorly to any remaining distal stump of the Achilles tendon. 12 These augmentation procedures have currently been abandoned because the clinical outcomes were better in those patients who did not receive augmentation. 2~ After completion of the reconstruction, the paratenon is repaired. The subcutaneous tissue and skin are closed. Compressive dressings and plaster splints are applied to maintain 15~ of ankle plantar flexion. Before being discharged, the patient is placed in a short leg n o n weight-bearing cast at 15~ of equinus for 4 weeks. When the patient returns after 4 weeks, the dressing is removed and the forefoot is placed on a foot rest with the patient seated on an examining table. The hip is flexed and allowed to stay in this position until the foot reaches neutral (Fig 12). The foot is then placed into a short leg walking cast or removable cast walker with the ankle at neutral for an additional 4 weeks, and weight-bearing is begun. A rehabilitation program for strengthening and range of motion is begun 8 weeks postoperatively. The patient is maintained in a removable cast walker for community ambulation until 10~ of dorsiflexion is obtained, and grade 4/5 strength is achieved. At home, ambulation is allowed with a 7/16-in heel lift during this time. The patients are then advanced to regular shoe wear and treatment is continued with a home strengthening program with theraband (Hygenic Corp, Akron, OH). Athletic activity is restricted for 6 months after surgery.
RESULTS In the original study group, results were classified by criteria established by Mann. 19 Three patients had excellent results. These patients had no pain postoperatively, no limitation of activities, no postoperative w o u n d
WAPNER AND HECHT
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Fig 8, A large towel clip can be used to complete the tunnel for passage of the tendon through the bone. Fig 6. The flexor hallucis Iongus is retracted into the posterior wound.
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Fig 7. The two drill holes are placed in the posteromedial portion of the calcaneus.
FLEXOR HALLUCIS LONGUS TENDON TRANSFER
Fig 9. The flexor hallucis has been pulled through the tunnel in the calcaneus. The length of tendon available for weaving through the Achilles is shown.
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Fig 11. Schematic representation of the flexor hallucis Iongus tendon woven through the Achilles tendon.
Fig 10. The tendon weaver is used to pierce the Achilles and the tips are widened slightly to create a tunnel through which the flexor hallucis can be passed.
complications, excellent strength, and independent tiptoe stance. Three patients had good results. These patients had at least neutral dorsiflexion, no postoperative wound complications, and returned to their preoperative jobs and preinjury athletic activities; however, they all experienced some minor degree of pain, minor decrease in strength or motion, or small limitation in their level of activity compared with their preinjury standards. One patient (case 4) had a fair result, with global weakness in all muscle groups of the ankle. He required a molded foot-ankle orthosis for prolonged ambulation. Nonetheless, he had no postoperative wound complications, dorsiflexion to 10 ~ above neutral, and bilateral tiptoe stance. He returned to his job as a physician and to his preinjury level of golfing. The patient did have lumbar decompression surgery 4 months after his Achilles tendon repair, and it is unclear how much this complication interfered with his long-term result. There were no poor results. All patients returned to work. All six patients who were involved in recreational athletic activities preinjury returned to the same athletic activities postoperatively. There were no reruptures. Six of seven patients were able to walk without assistive devices. All patients regained at least neutral dorsiflexion and normal plantar flexion.
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Fig 12. The patient is seated on an examining table with the hip flexed and the forefoot resting on a foot rest. Gravity and the weight of the patient's leg are used to allow the leg to come to a neutral position, and then a removable cast boot is applied.
WAPNER AND HECHT
DISCUSSION
REFERENCES
A l t h o u g h m a n y p r o c e d u r e s h a v e b e e n described in the p a s t for r e c o n s t r u c t i o n of the chronic Achilles t e n d o n r u p t u r e , w e believe that this technique of reconstruction w i t h the flexor hallucis l o n g u s theoretically p r o v i d e s multiple a d v a n t a g e s o v e r the p r e v i o u s techniques described. First, the t e n d o n is long a n d durable, a n d its muscle is s t r o n g e r t h a n o t h e r t e n d o n t r a n s f e r s p r e v i o u s l y described. Silver 21 described the relative s t r e n g t h percentages of the m u s c l e s a r o u n d the foot a n d ankle. The gastroc-soleus c o m p l e x g e n e r a t e d a s t r e n g t h of 49.1%. H o w e v e r , the next s t r o n g e s t plantar flexor w a s n o t e d to be the flexor hallucis longus, w i t h a s t r e n g t h of 3.6%. The flexor d i g i t o r u m l o n g u s a n d p e r o n e u s brevis w e r e n o t e d to h a v e s t r e n g t h of 1.8% a n d 2.6%, respectively. Second, the axis of contractile force of the flexor hallucis longus m o s t closely r e p r o d u c e s that of the Achilles tendon. Third, the flexor hallucis l o n g u s fires in p h a s e with the gastroc-soleus muscle. Fourth, its a n a t o m i c proximity m a k e s the surgical technique easier a n d the n e e d to disturb the n e u r o v a s c u l a r b u n d l e or lateral c o m p a r t m e n t muscles is avoided. 22 H a r v e s t i n g the flexor hallucis longus in the m i d f o o t a d d s an additional 10 to 12 cm of t e n d o n length c o m p a r e d with the technique of H a n s e n . is This allows w e a v i n g of h a r v e s t e d t e n d o n t h r o u g h the Achilles as described b y M a n n , 19 b u t w i t h a s t r o n g e r m o t o r unit. This fifth a d v a n tage allows u s e of the a s s e t s of b o t h H a n s e n ' s a n d M a n n ' s techniques. Finally, transfer of the flexor hallucis longus m a i n t a i n s the n o r m a l muscle balance of the ankle by transferring a muscle of the s a m e original function (ie, plantar flexor to plantar flexor). Transfer of a muscle such as the p e r o n e u s brevis substitutes an evertor for a plantar flexor, resulting in a less functional repair b y t e n d o n transfer s t a n d a r d s a n d an u n k n o w n effect on the function of the foot a n d ankle b y partial loss of eversion strength. Analysis of the data also strongly s u g g e s t e d that functional o u t c o m e is strongly correlated w i t h patient effort a n d c o m p l i a n c e w i t h the p o s t o p e r a t i v e rehabilitation/ physical t h e r a p y . All patients w h o o b t a i n e d excellent functional results w e r e f o u n d to be highly c o m p l i a n t with the t h e r a p y prescribed, as d o c u m e n t e d b y b o t h the office record a n d the p a t i e n t ' s o w n report. T h o s e w i t h g o o d o u t c o m e s w e r e less consistently c o m p l i a n t w i t h the thera p y prescribed. The fair o u t c o m e (case 4), b y his o w n report, w a s not c o m p l i a n t w i t h the prescribed rehabilitation. In s u m m a r y , g o o d restoration of function can be obtained b y surgical t r e a t m e n t of chronic r u p t u r e s of the Achilles t e n d o n w i t h flexor hallucis longus t e n d o n recons t r u c t i o n . This a p p r o a c h p r o v i d e s a d v a n t a g e s o v e r techniques p r e v i o u s l y described in the literature, a n d the majority of patients can expect excellent or g o o d return of function after surgery.
1. Howard CB, Winston I, Bell W, et al: Late repair of the calcaneal tendon with carbon fiber. J Bone Joint Surg [Br] 66:206-208, 1984 2. Lead RB, Smith L: Non-surgical treatment of tendo achilles rupture. J Bone Joint Surg [Am] 54:1398-1407, 1972 3. Nistor L: Surgical and non-surgical treatment of Achilles tendon rupture. A prospective randomized study. J Bone Joint Surg [Am] 63:394-399, 1981 4. Carden DG, Noble J, Chalmers J, et al: Rupture of the calcaneal tendon. The early and late management. J Bone Joint Surg [Br] 69:416-419, 1987 5. Inglis AE, Scott WN, Sculco TP, et al: Ruptures of the tendo achilles. An objective assessment of surgical and non-surgical treatment. J Bone Joint Surg [Am] 58:990-993, 1976 6. Freilinger G, Scheuba G, Schurer-Waldheim H: Die Achillessehnenruptur und ihre naht mit hilfe der plantarissehne. Muschr Unf Heilk 73:523, 1970 (abstr) 7. Bugg El, Boyd BM: Repair of neglected rupture or laceration of the Achilles tendon. Clin Orthop 56:73-75, 1968 8. Bosworth DM: Repair of defects in the tendo achilles. J Bone Joint Surg [Am] 38:111-114, 1956 9. Lynn TA: Repair of the torn Achilles tendon, using the plantaris tendon as a reinforcing membrane. J Bone Joint Surg [Am] 48:268272, 1966 10. Ozaki J, Fujiki J, Sugimoto K, et al: Reconstruction of neglected Achilles tendon rupture with marlex mesh. Clin Orthop 238:204208, 1989 11. Levy M, Velkes S, Goldstein, et al: A method of repair for Achilles tendon ruptures without cast immobilization. Preliminary report. Clin Orthop 187:199-204, 1984 12. Lieberman JR, Lozman J, Czajka J, et al: Repair of Achilles tendon ruptures with dacron vascular graft. Clin Orthop 234:204-208, 1988 13. Kato YP, Dunn MG, Zawadsky JP, et al: Regeneration of Achilles tendon with a collagen tendon prosthesis. Results of a one-year implantation study. J Bone Joint Surg [Am] 73:561-574, 1991 14. Schedl R, Fasol P: Achilles tendon repair with the plantans tendon compared with repair using polyglycol threads. J Trauma 19:189194, 1979 15. Hansen, Sigvard T: Trauma to the heel cord, in Jahss MH (ed): Disorders of the Foot and Ankle (ed 2). Philadelphia, PA, Saunders, 1991, p 2357 16. Teuffer AP: Traumatic rupture of the Achilles tendon. Reconstruction by transplant and graft using the lateral peroneus brevis. Clin Orthop North Am 5:89-93, 1974 17. Turco VJ, Spinella AJ: Achilles tendon rupture-peroneus brevis transfer. Foot Ankle 7:253-259, 1987 18. Turco V, Spinella AJ: Team physician #2. Peroneus brevis transfer for Achilles tendon rupture in athletes. Orthop Rev 17:822-824, 1988 19. Mann RA, Holmes GB, Seale KS, et al: Chronic rupture of the Achilles tendon: A new technique of repair. J Bone Joint Surg [Am] 73: 214-219, 1991 20. Wapner KL, Pavlock GS, Hecht PJ, et al: Repair of chronic achilles tendon rupture with flexor hallucis longus tendon transfer. Foot Ankle 14(8):443-449, 1993 21. Silver RL, DeLa Garza J, Rang M: The myth of muscle balance. A study of relative strengths and excursions of normal muscles about the foot and ankle. J Bone Joint Surg [Br] 67:432-437, 1985 22. Wapner KL, Allardyce T, Shea J, et al: Anatomic basis for tendon selection in reconstruction of ruptures of the Achilles and posterior tiblal tendon. Presented at American Orthopaedic Foot and Ankle Society Summer Meeting, Napa, CA, July, 1992
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