Pre-clinical study: development of the surgical procedure<\/p>\n
The cadaveric specimens were placed prone, and a complete percutaneous tenotomy of the Achilles tendon was performed 5\u00a0cm proximal to the insertion on the calcaneus, simulating a complete rupture. The sural nerve was then mapped throughout its course using ultrasound to accurately place the portals for surgery and prevent nerve entrapment or damage (Fig.\u00a01<\/a>).<\/p>\n Fig. 1 Sural nerve mapping with US<\/p>\n No skin incisions were made. At the point where the proximal and distal sutures meet, minimal stretching of the skin was performed with the tip of forceps to avoid skin bridges between the stitches.<\/p>\n We used a symmetrical Bunnell-type suture configuration, starting 6\u20138\u00a0cm proximal to the ATR. The proximal suture ends at the proximal end of the tendon stump. Each medial-to-lateral or lateral-to-medial cross-suture was advanced approximately 2\u00a0cm (Figs.\u00a02<\/a> and 3<\/a>, and Fig.\u00a04<\/a>).<\/p>\n The sural nerve usually runs from lateral, in the distal area, posterior to the fibular malleolus, lateral to the Achilles tendon, to medial in the medial third of the calf, crossing over the gastrocnemius tendon. Care is required to pass the suture without trapping the sural nerve. The first pass is normally deep to the nerve and, at some point distally, depending on the anatomy of the nerve, the suture is superficial to the tendon.<\/p>\n In the proximal stump, the needle and thread must be advanced carefully in the lateral area to avoid damaging or trapping the sural nerve. The procedure was performed under ultrasound guidance to avoid damaging the sural nerve and to ensure that the tendon was appropriately sutured (Fig.\u00a02<\/a>).<\/p>\n Fig. 2 Ultrasound-guided passage of the needle and suture in the lateral area of the proximal stump with direct vision of the sural nerve<\/p>\n Fig. 3 In the distal stump, passage of the needle and suture is usually medial to the nerve, as this runs from distal and lateral to proximal and medial<\/p>\n We repeated the procedure with another suture starting in the distal portion stump of the tendon and advancing proximally.<\/p>\n The distal ends of the suture were guided through the distal puncture of the proximal end suture to tie the proximal suture to the distal one. Reliable approximation of both ends of the tendon was thus achieved and verified with ultrasound.<\/p>\n We finished the Bunnell-type suture emerging at the point of the proximal ends of the suture (Fig.\u00a04<\/a>). Therefore, we did not need to enlarge the emergence points of the suture more than 1\u20132\u00a0mm if a skin bridge remains between the two stitches.<\/p>\n In addition, we achieved maximum tension when we tie the proximal and distal ends of 2 independent sutures by driving one suture to the point where the other one ends.<\/p>\n The ankle was kept in full plantar flexion while the sutures were tied (Fig.\u00a04<\/a>).<\/p>\n Fig. 4 The ends of both the proximal and the distal sutures are tied in the lateral and medial aspects of the ruptured tendon. The approximation of the ends of the Achilles tendon is verified using ultrasound<\/p>\n Postsurgical dissection enabled us to verify that the sural nerve was not damaged, and that full juxtaposition of the tendon stumps had been was achieved (Fig.\u00a05<\/a>).<\/p>\n Fig. 5 Verification of the sural nerve via dissection of the specimen<\/p>\n Clinical study<\/p>\n The clinical series comprised 11 patients (10 males and 1 female; mean age: 54 years (range 42 to 65) in whom the ATR was located by ultrasound and the sural nerve was carefully identified (Fig.\u00a06<\/a>). TThe time elapsed from the rupture of the Achilles tendon until the surgery was performed was 8.6 days (3\u201314). No patients had systemic diseases.<\/p>\n The skin was prepared in the usual fashion, obtaining a sterile field. Anesthesia involved sedation and local infiltration with 20 mL of local anesthetic (20 mL bupivacaine\/adrenaline, 5\u00a0mg\/mL\u2009+\u20090.005\u00a0mg\/mL) in the puncture areas and tendon defects, approximately 4 to 6\u00a0cm proximal and distal to the tendon defect (Fig.\u00a07<\/a>). No tourniquet was used.<\/p>\n At the end of the procedure, the patient was immobilized in a below knee cast, with maximum plantar flexion of the ankle.<\/p>\n![\"figure](\"https:\/\/www.newsbeep.com\/au\/wp-content\/uploads\/2025\/09\/13018_2025_6098_Fig1_HTML.png\")
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