Abstract
Background Autologous breast reconstruction (ABR) has grown in popularity due to improved aesthetic
and long-term patient reported outcomes, but data regarding sensory reinnervation
of autologous flaps remain limited. Traditionally, the lateral cutaneous branch of
the fourth intercostal nerve has been used for flap neurotization, but the use of
the anterior cutaneous branch of the intercostal nerves (ACB) offer a more optimal
location to the microsurgical field when using internal mammary vessels for the microanastomosis.
This study aimed to evaluate the optimum ACB recipient site level for sensory nerve
coaptation in ABR.
Methods Twelve hemi-chests were dissected from six fresh cadaveric females. Costal cartilages
were removed and the anterior cutaneous intercostal nerve (ACB) and the lateral (subcutaneous)
division of the anterior cutaneous branch (LACB) of the intercostal nerve were exposed.
Anatomical measurements were recorded, and nerve samples were evaluated histologically
with carbonic anhydrase staining to differentiate sensory fascicles. Assessment of
fascicular diameter, axonal counts, and fascicular area were compared.
Results A total of 75 nerve specimens were assessed. The ACB was identified at all levels
(100%) and the subcutaneous LACB was noted consistently in the second to fourth rib
space (96% cadavers), with a median length of 43, 37.5, and 37 mm, respectively. Across
all rib spaces, the fascicular and axonal counts were comparable between the LACB
and ACB. Nerves in the second intercostal space had a significantly larger mean fascicular
area mean (112,816 ± 157,120 µm2) compared with that in the fourth (mean 26,474 ± 38,626 µm2), p = 0.03. Axonal count of sensory fascicles was the highest in the second intercostal
nerves (p < 0.05).
Conclusion This study provides anatomical and histological basis to determine the optimum recipient
site choice for sensory coaptation in microsurgical breast reconstruction. This would
aid in operative decision-making regarding the ideal recipient anterior cutaneous
intercostal nerve branches for recipient site coaptation in ABR.
Keywords
autologous breast reconstruction - deep inferior epigastric perforator - sensate flap
- intercostal nerve - nerve repair