Association Between Thenar Musculature and Carpal Tunnel Syndrome.

Background: Dynamic forces acting on the transverse carpal ligament (TCL) may influence the mechanics of the carpal tunnel (CT), thus affecting the occurrence of CT syndrome (CTS). Previous studies demonstrated an association between muscle overlying the CT and the diagnosis of CTS. Understanding the location of insertion/origin of the thenar musculature will allow mechanical analysis of the forces applied to the TCL during performance of individual tasks. Our purpose was to determine the location of muscle overlying the CT on magnetic resonance imaging (MRI) in CTS and controls. Methods: Case-control study of 21 normal adult wrist MRI scans. MRI measurements were performed on an axial cut at the level of the hook-of-hamate. Median nerve cross-sectional area (CSA), median nerve shape and increased signal intensity within the CT were associated with CTS. The amount and length of muscle crossing the midline and the CT on the same cut was measured and the association with the occurrence of CTS was analysed. Results: We found an inverse relationship between the amount of muscle crossing the midline and the size of the CT, and a direct relationship with occurrence of CTS p less than 0.01, but no differences regarding length of muscle crossing the midline. Conclusions: This study supports an association between the thenar musculature location relative to the CT and the predictors of CTS on MRI. Since the location of muscle origin/insertion is variable, their effect may differ accordingly, therefore, further study is needed to describe the exact location of origin/insertion and its differential dynamic or static effect on the pathogenesis of CTS. Level of Evidence: Level IV (Diagnostic).

Lateral hernia secondary to colorectal submucosal resection repaired by robotic-assisted approach: Case report.

INTRODUCTION AND IMPORTANCE: Lateral abdominal wall defects are a rare event and commonly result from iatrogenic causes and trauma. We report the first known case of flank hernia after endoscopic submucosal resection of a colonic polyp complicated by colonic perforation. CASE PRESENTATION: This is a case of a 50-year-old male who underwent endoscopic colonic resection complicated by perforation of the colon. Eight months later, he presented with an enlarging, asymptomatic left flank bulge. CT showed a large flank hernia which was successfully repaired using a robotic transabdominal preperitoneal (TAP) approach. CLINICAL DISCUSSION: The hypothesis is that the endoscopic resection with colonic perforation caused an iatrogenic injury to the abdominal wall creating a lateral abdominal hernia. Injury to abdominal wall musculature may take months to develop into a clinically apparent hernia. Flank hernias can be successfully repaired using a robotic minimally invasive approach. CONCLUSION: Flank bulge and hernias must be included or at least be considered as consequence of a potential complication from endoscopic colonic perforation. Surgeons and endoscopists must be aware of this potential complication and its latent presentation. This case stresses the importance of long-term outcomes monitoring, particularly with innovative procedures.