Fascial Turn-Down Flap Repair of Chronic Achilles Tendon Rupture 19

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turn-down ﬂ aps: ﬁ rst one that was described by Christensen in 1931 and Gerhardt in 1937, followed by the technique described by Lindholm in 1959.

Operative Technique (Central Flap)

The patient is placed in prone position. Anesthe- sia should ensure maximal muscle relaxation.

Make a linear/curvilinear medial incision (to min- imize the risk of injuring the sural nerve) from the midcalf to the calcaneus, taking care not to cross the midline in the distal part, in order to avoid scarring the tendon (Fig. 19.1). Incise the deep fascia in the midline after freeing it from the skin, thus making sure that the fascial incision lies fully under the skin fl ap. The site of the Achilles tendon rupture and the proximal gastrocnemius muscle are thus exposed (Fig. 19.2). Debride the tendon stumps as necessary, excising any fi brous tissue that may have formed in between the torn edges (Fig. 19.3). Then appose the refreshed ends with a box type of mattress suture, if possible, using heavy absorbable sutures. Place the foot in as much plantarfl exion as required for proper appo- sition. Next, raise a fl ap approximately 2.0–2.5 cm broad and 7–8 cm long (depending on the gap to be bridged in case of neglected ruptures) from the middle of the proximal tendon and the gastrocnemius aponeurosis (Fig. 19.4), thus creating a central fl ap. Make sure that the fl ap is long enough to bridge the gap and it can be sutured securely to the distal tendon. Leave the fl ap attached for at

Introduction

Fascial turn-down ﬂ aps can be used for an ana- tomic repair of chronic Achilles tendon rupture.

This technique allows one to strengthen the suture line and diminish the formation of adhesions between the sutured site and the skin.^1–5

Historical Perspective

Christensen¹ and Gerhardt² separately described similar techniques. After suturing the tendon ends, they raised a distally based fl ap from the gastrocnemius aponeurosis and turned it over itself across the suture line and sutured it to the distal part of the Achilles tendon. Silfverskiold⁶ twisted the gastrocnemius fl ap through 180 degrees before suturing it distally. This resulted in the smooth surface of the fl ap coming in contact with the skin, thereby decreasing the chance of adhesion between the fl ap itself and the overlying tissue. Toygar⁷ described a technique for chronic ruptures, where it is diffi cult to regain continuity between the two ends. The gap is bridged by two fl aps, raised from the two ends of the tendon, one from the medial side and the other from the lateral side. Weisbach⁸ described another technique to address the same problem. Along with the gastrocnemius fl ap, he raised another fl ap from the distal stump of the Achilles tendon, and sutured these two fl aps in order to bridge the gap.

In this chapter we describe two of the most commonly used techniques using the principle of

Fascial Turn-Down Flap Repair of Chronic Achilles Tendon Rupture

S. Ghosh, P. Laing, and Nicola Maffulli

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19. Fascial Turn-Down Flap Repair of Chronic Achilles Tendon Rupture 175

FIGURE 19.1 Medial skin incision.

FIGURE 19.2 Tendon sheath exposed and fibrous tissue (which is bridging the defect) visualized.

least 3 cm proximal to the rupture. Next, turn the central ﬂ ap upside down on itself and suture it to the distal stump with interrupted sutures (Fig.

19.5). Close the defect in the proximal tendon and gastrocnemius muscle belly with interrupted sutures. Close the tendon sheath and the deep fascia, followed by skin closure. Apply a plaster cast with the foot in gravity equinus.

Aftertreatment

At two weeks remove the cast, check the wound, and remove the sutures. Apply another short leg cast, with the foot in gravity equinus, for two weeks. After four weeks from surgery, bring the foot gradually to the plantigrade position over the next two weeks by serial changes of cast. The

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FIGURE 19.3 Refreshed tendon ends after adequate excision of fibrous tissue.

FIGURE 19.4 A central flap raised from the proximal tendon and gastrocnemius muscle.

FIGURE 19.5 The central flap is turned down on itself to bridge the gap.

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patient can gradually resume walking with partial weight bearing on crutches during a two-week period. At six to eight weeks, apply a short leg walking cast with the foot in the plantigrade position, and allow full weight bearing. Alterna- tively, use a removable brace allowing only plan- tarﬂ exion. Begin gentle active range-of-motion exercises and isometric ankle exercises. Toe raises, progressive resistance exercises, and propriocep- tive exercises, in combination with a general strengthening program, constitute the third stage of rehabilitation. At 12 weeks, start using a reverse-90-degree ankle stop brace or similar device (if not already in use) and continue until a nearly full range of motion and strength 80% that of the opposite extremity has been obtained, usually within 6 months. In reliable, well-super- vised patients with good tissue repair you may accelerate this program, with earlier use of dorsi- ﬂ exion-stop orthoses and active range-of-motion exercises.

Discussion

This technique is easy and simple to carry out.

However, there is a risk of adhesion as the raw inner surface of the ﬂ ap comes in contact with the subcutaneous tissue. This can be overcome by the modiﬁ cation proposed by Silfverskiold and dis-

cussed earlier. Lindholm noted avascular necrosis of the turned-down ﬂ ap, and proposed his technique to avoid a possible injury to the vascularity of the ﬂ ap.

Operative Technique (Medial and Lateral Flaps)

The initial steps, until the tendon is exposed, are the same as described above.

The Achilles tendon rupture and lower part of the gastrocnemius muscle bellies are thus exposed (Fig. 19.3). Next, raise a fl ap approximately 1.0 cm broad and 7–8 cm long (depending on the gap to be bridged in chronic ruptures) from either side of the proximal tendon and the gastrocnemius aponeurosis about 0.5–1 cm from the midline (Fig. 19.6). Leave these fl aps attached at a point 3–4 cm proximal to the tendon suture. Try to use the superfi cial layer of the aponeurosis only, though at times this is diffi cult. However, the detachment of the superfi cial layer is easier if you make the longitudinal incisions fi rst, and then undermine the fl ap, before dividing it proximally.

After creating the ﬂ aps, twist them 180 degrees backward on themselves so that the smooth exter- nal surface lies next to the subcutaneous surface as you turn it distally over the rupture. Close the

FIGURE 19.6 The two flaps are raised from the proximal end.

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178 S. Ghosh et al.

proximal defect in the gastrocnemius aponeurosis with interrupted sutures (Fig. 19.7). Suture the ﬂ aps to each other in the midline and to the distal stump of the tendon using interrupted sutures (Figs. 19.8 and 19. 9). Close the tendon sheath and the deep fascia carefully (Fig. 19.10). Appose the subcutaneous tissues together and close the skin wound. After suturing the stumps of the

FIGURE 19.7 The flaps are turned down on themselves through 180° to reach the distal end and the proximal defects are sutured.

Achilles tendon, gradually reduce the plantarﬂ exion of the foot during the rest of the operation, by careful, continuous pressure against the sole of the foot. This ensures the tendon is progressively stretched, so that at the end of surgery the foot can be placed with only 5–10 degrees of plantarﬂ exion. Apply a plaster cast with the foot in gravity equinus.

FIGURE 19.8 The flaps are sutured to each other.

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FIGURE 19.9 The combined flap is sutured to the distal stump.

FIGURE 19.10 The paratenon is closed over the tendon.

Aftertreatment

This is the same as in the previous technique.

Discussion

Lindholm published this technique with results on 20 patients. He described better cosmetic results and lack of adhesion, while maintaining good functional outcome.³ He described one patient with superﬁ cial infection of the wound, one with re-rupture, and one with a mild degree

of skin fi xity. Lindholm primarily described his technique only for acute ruptures and did not rec- ommend its use in chronic ruptures, as he believed that “a free gliding surface forms against the subcutaneous tissue” in old ruptures and “plastic procedures in these cases greatly impede suture of the skin.” However, we use it in cases of neglected ruptures only.⁵ The rationale behind fashioning two fl aps instead of one central fl ap, as described by Silfverskiold, was to preserve vascularity of the tendon, which is mostly centrally distributed, thus preventing necrosis of the fl aps.³