The anatomical landmarks effective in the localisation of the median nerve during orthopaedic procedures.

BACKGROUND: The aim of this study was to create a safe zone for surgeons who perform procedures in the wrist to avoid iatrogenic damage to the median nerve (MN) by identifying anatomical landmarks using ultrasound (USG). MATERIALS AND METHODS: We measured the distances between the MN and two easily identifiable anatomical landmarks at the level of the proximal border of carpal ligament using USG. RESULTS: A total of 57 volunteers (n = 114 upper limbs) were included in this study. Our main findings revealed that the distance from the flexor carpi radialis tendon to MN (FCR-MN) was 7.87 mm (95% confidence interval 7.37-8.37) and the distance from flexor carpi ulnaris tendon to MN (FCU-MN) was 19.09 mm (95% confidence interval 18.51-19.67). CONCLUSIONS: The tendons of FCR and FCU are easily identifiable landmarks that can be distinguished using simple palpation. Based on our USG findings, the area around FCR should be carefully navigated to avoid iatrogenic injury to the MN during surgical procedures around the carpal tunnel.

Computer-assisted assessment of the histological structure of the human sural nerve.

BACKGROUND: The aim of this study was to assess the histological structure (cross-sectional area - CSA, number of nerve bundles) of the human sural nerve at the level above the lateral malleolus, using computer-assisted image analysis. MATERIALS AND METHODS: This study has been conducted using sural nerves dissected from cadavers during routine autopsies. The harvested tissues samples were dehydrated, embedded in paraffin, sectioned at 4 µm and stained with haematoxylin and eosin. Each cross-section was photographed (16 × magnification) and the images were analysed using Java ImageJ. RESULTS: The studied group comprised 12 women and 25 men (mean age 60.1 ± 15.7 years), yielding a total of 74 sural nerves (37 right vs. 37 left). The mean ± standard deviation CSA of the sural nerve was 0.14 ± 0.07 cm2. The mean number of nerve bundles in the sural nerve was 10.5 ± 6.0. In terms of gender and side, neither the CSA (p = 0.45 and p = 0.79, respectively) nor the number of nerve bundles revealed any differences (p = 0.34 and p = 0.47, respectively). Strong negative correlations were noted between the age of the donors and the sural nerve CSA (r = -0.69,p = 0.02), as well as the number of nerve bundles (r = -0.57, p = 0.06). CONCLUSIONS: This study shows that there are no statistical differences between the CSA and the number of nerve bundles in the sural nerve when compared by gender and side of the lower limb. This study also allows drawing the conclusion that the sural nerve degenerates with age in terms of both the CSA and the number of nerve bundles.