Dados do Trabalho

Título

DESCRIPTION OF SPECIFIC PORTAL FOR ECU TENOSCOPY: ANATOMICAL SAFETY STUDY

Introdução e Objetivo

The tendon of the extensor carpi ulnaris can be arthroscopically visualized with 6R portal enlargement. Moreover, it is possible to create a portal to facilitate its tenoscopy. The dorsal branch of the ulnar nerve may be at risk during portal creation.

Material e Método

We performed an anatomical study with 15 upper limbs of fresh human cadavers to describe the relationship of the dorsal branch of the ulnar nerve to the 6R and ECU portals.

Resultados

We observed that the proximal ECU portal could be considered safe as regarding to the risk of injury to the nerve: the area one centimeter proximal and distal forms a rectangle that we have called "green zone".

Discussão

We have described a proximal portal specific for the ECU tendon, which we called the proximal ECU (PECU) portal, 2 cm proximally to the UCJ. Upon the analysis of our results, we have appraised the area around the PECU portal as safe regarding the risk of DBUN injury. Limousin et al. have classified high-risk for injury a distance of less than 3.5 mm between the portal site and the nerve passage in small joint arthroscopy; a distance between 3.4 and 4.5 mm is considered to pose a medium risk; and a distance of more than 4.5 mm is tagged as low risk (Limousin et al, 2018). With the measurements obtained, we understand that the PECU portal can be considered safe regarding the risk of injury to the DBUN, as well as 1 cm proximal and distal to it, forming a rectangle that we have regarded as a “green zone” to access the SEC. The more distal region, which goes from 1 cm proximal to 1 cm distal to the 6R portal line, forms a rectangle that we have called the “yellow zone”, with medium risk of lesion. The most distal region, on the other hand, which forms a rectangle 1 to 2 cm distal to the 6R portal, aligned with the SEC, is called the “red zone” because it is where the DBUN superficially crosses over the ECU tendon.

Conclusão

The distal region forming a rectangle one to two centimeters distally to the 6R portal and aligned with the sixth extensor compartment is called the "red zone", because it is where the nerve crosses over the ECU tendon.