Percutaneous Achilles tendon tenotomy in clubfoot patients with a 22 gauge needle in a low-resource setting

Introduction

Ponseti treatment is well-established as the gold standard for treatment of idiopathic clubfoot in high-income countries and middle- and low-income countries (LMICs). ¹ Percutaneous Achilles tendon lengthening is an integral part of this method and is done in up to 90% of affected patients. ² The tenotomy is usually performed in out-patients using a scalpel blade under local anesthesia; however some surgeons prefer general anesthesia which grossly increase the cost of procedure and also adds risks. A technique performing a tenotomy with a simple 16 Gauge needle in the clinic making the procedure much simpler is described. ³

Only an estimated 15% of children with clubfoot in LMICs have access to Ponseti treatment and even less will finish the entire treatment course.^1,4 Various barriers to clubfoot treatment have been identified, including lack of trained personnel in a clinic close to home, lack of parents’ understanding of the treatment and its cost. ⁵ By adapting the technique described to a low-resource setting some of these barriers can be addressed. Using a needle instead of a blade makes the procedure less cumbersome, easier to learn and easier to understand for the provider, family and the patient.

Surgical technique

Before initiating an Achilles tenotomy, the provider has to assure that all prerequisites have been met: plantigrade foot, 40° of abduction and consent of the patient's guardian. The latter is normally asked to leave the room when the surgeon is ready to start the procedure. An overview of the set-up, including the position of the surgeon and the assistant, is shown in Figure 1. The patient is placed in supine position on the examination table with an assistant holding the pelvis with one hand and the contralateral leg with the other. The surgeon holds the affected leg himself throughout the entire procedure. The knee is put in a slightly flexed position and the hip is abducted and externally rotated so that the posterior aspect of the ankle rests in front of the surgeon performing the tenotomy. We prefer the knee to be only slightly flexed so that the gastrocnemicus muscle remains under sufficient tension and the Achilles tendon is taut, by holding the foot in the non-dominant hand in full dorsiflexion. The posterior aspect of ankle is disinfected with povidone iodine-soaked gauze. The tendon is palpated with the index finger while wearing sterile gloves. As a local anaesthetic, lidocaine 0.5 mL is infiltrated, using a 1cc insulin syringe, 1.5 cm above the insertion of tendon on its anteromedial edge and directed slightly in an anterolateral direction to avoid the posteromedial neurovascular bundle. Afterwards, a 22G-needle is inserted at the same insertion site to sense the tendinous fibers. Using the tip of the needle as a cutting device, these are divided into medial to lateral direction. Any stabbing movements are avoided as the tip of the needle is considered as a cutting blade. After 2 to 3 movements, a pop is felt and the foot immediately achieves a dorsiflexion of c.15–20°. A small swab is put over injection site to avoid any blood staining to the cast A long leg cast is applied in full correction and maximum dorsiflexion with the knee flexed as described in the Ponseti protocol. (Photo 1 shows the positioning of the surgeon and the assistant during the intervention.)

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Figure 1.

Position of surgeon and assistant during tenotomy.

Discussion

The use a 22G instead of the 16G-needle as previously described is preferred, because it is more readily available and less invasive, especially in neonates. Children often present with signs of malnutrition or undernutrition, where the skin is very fragile; the use of a 16G needle or blade may readily cause significant skin defects. ⁶ Prior concerns that any needle smaller than 16G would not be stiff enough to perform the procedure have been laid to rest.

We observed that after infiltration with local anesthetic, it was difficult for the surgeon to palpate the tendon adequately. The sole use of EMLA cream has been therefore advocated, arguing that the cutting of the tendon itself is not painful. ³ However, EMLA cream is often unavailable, and applying the cream 30–120 min before the intervention is administratively cumbersome given the obvious time, space and financial constraints. A locally adapted solution could be to change the sequence of the intervention, by first performing the tenotomy with a 22G-needle and then injecting the lidocaine afterwards using the same needle. To our knowledge no-one implements this approach on a routine basis yet, which begs the question whether anaesthetic is needed at all.

We were able to show that the needle tenotomy technique can be implemented in a low-resource setting, and can be performed using only one assistant and materials that are locally and readily available for the same cost A randomized control trial comparing the effectiveness and complication rate between needle and blade tenotomy is currently ongoing at our centre (clinicaltrials.gov NCT04897100). Preliminary data from our pilot study comparing 50 tenotomies showed no difference between achieved dorsiflexion or complication rate between both techniques. Our educational videos as referenced may be of use in demonstrating this method.