Refinements of nerve repair with connector‐assisted coaptation

Abstract

Peripheral nerve repair can be very rewarding for both surgeon and patient when expected outcomes are achieved. In many cases, however, the results are suboptimal due to number of possible objective and technical reasons. Although we cannot influence patent's comorbidities, the extent or mechanism of the nerve injury, we may help optimize technical details when aiming towards improved outcomes. While the suture coaptation for primary nerve repair or nerve reconstruction with grafting served as the reconstructive standard for many decades, technical imperfections remain threats to reconstructive goals. Tension, fascicular misalignment generated by over tightening suture coaptation, deeply placed sutures, reactive scarring to foreign material at anastomosis site, may all negatively affect axonal regeneration. As the goal of every nerve repair is to have ideally opposed tension free nerve fascicles, protected from the deleterious effects of the wound bed. The utilization of coaptation aids to overcome the challenges of nerve repair has been suggested as an alternative to the classical suture repair. A review of clinical literature was performed to assess the evidence for this technique and the critical success factors to consider when implementing this technique. Twelve clinical studies met criteria, majority suggesting improved outcomes by the utilization of a coaptation aid. Most commonly reported improvements were improved sensory outcomes, reduced tenderness or pain at the coaptation site and reduced operative time. The current clinical evidence data suggests that utilization of a coaptation aid is a technical innovation to help provide better nerve repair and reconstructive functional outcomes.

Application of a Porcine Small Intestine Submucosa Nerve Cap for Prevention of Neuromas and Associated Pain

“…33 For example, nerve allograft has been used to reconstruct nerves after resection of painful neuromas-in-continuity 33 and conduits, when placed over a nerve coaptation, have been shown to reduce the likelihood of pain at the coaptation by 50%. 34 However, although nerve caps have been utilized as a method to try and prevent neuroma development in the past, they were either made from nonbiologic materials such as silicone or from autologous tissues such as vein or epineurium. 12,21 These treatments have not gained in popularity, likely due to the fact that silicone can cause problematic reactions when implanted in the body and autologous tissue requires extra operative time, introduces risks with donor site morbidity, and can pose an additional technical challenge while not guaranteeing the containment of axons within the cap.…”

Strategies for innervation of the neophallus

“…When a tension-free coaptation is not possible, synthetic or biological conduits may be used [61] . In the field of peripheral nerve surgery, connector-assisted coaptations may decrease operative time, improve sensory outcomes, and decrease pain [62] . Multiple pharmacologic agents, such as Acetyl-L-carnitine, testosterone, and various growth factors have been investigated as a means to enhance nerve regeneration [63,64] .…”

Alternativas Microquirúrgicas (Autoinjertos Nerviosos / Aloinjertos Nerviosos / Conductos Nerviosos) para la Recuperación Sensitiva Funcional de Nervio Alveolar Inferior y Nervio Lingual: Revisión de la Literatura.

“…Aunque los conductos pueden tener una indicación limitada en la reconstrucción para brecha nerviosa, varios estudios respaldan su uso como complementos de las reparaciones primarias y de las reconstrucciones de brecha mediante aloinjertos (18,21,26,27) . Funcionan como una barrera física entre el nervio reparado y el entorno externo, que protege y contiene las proteínas de la matriz extracelular necesarias para una curación óptima en el sitio de reparación, así como para prevenir el crecimiento excesivo y el escape axonal (28,29,30,31,32) . Wilson et al, realizaron un estudio comparando envolturas de conducto de colágeno de tipo I con envolturas de submucosa de intestino delgado porcino en reparaciones primarias de NL.…”

“…Encontraron que no había diferencias en las tasas de RSF para ninguno de los grupos y que los 43 pacientes incluidos en el estudio tenían una puntuación igual o superior a S3 en la escala CIM (18) . Si bien el tamaño de la muestra del estudio no fue lo suficientemente grande como para demostrar diferencias estadísticamente significativas entre las reparaciones envueltas sin conector y las reparaciones envueltas con conector, creemos que este es un complemento útil para optimizar la recuperación sensitiva (28,29,33) .…”