Myosonographic study of abdominal wall dynamics to assess donor site morbidity after microsurgical breast reconstruction with a DIEP or an ms-2 TRAM flap

Abstract

Background: Currently, autologous breast reconstruction with a free tissue transfer from the lower abdomen is considered to be a safe method that provides a stable long-term solution. The DIEP-flap and the ms-2-TRAM-flap reconstructions have helped reduce donor site morbidity. In order to assess the potential differences between these techniques, we carried out myosonographic evaluations that assessed the muscle dynamics pre- and post-operatively. In addition to investigating the properties of the rectus abdominis muscle post-operatively, this prospective study also allowed us to analyse the muscle preoperatively and to investigate the prospects for harvesting a DIEP-flap as opposed to a TRAM-flap.

Materials and methods: Sixty patients underwent breast reconstruction with 71 (11 bilateral) free abdominal wall flaps (DIEP-: n = 48; ms-2-TRAM-flap: n = 23). Myosonographic examinations were performed preoperatively and at 3 and 6 months post-operatively. The thickness of the muscle at relaxation and maximum contraction and the difference between the muscle thickness measured at the two states were measured. A general-linear-model (GLM) was used for statistical analysis. The main variable was the surgical method, and the co-variables included BMI and patient age. The decision on whether to harvest a DIEP- or ms-2-TRAM-flap was made intra-operatively and based on the dominant perforator.

Results: It shows that the patients who underwent breast reconstruction with a DIEP-flap had significantly better muscle function (p < 0.05) in the follow-up. In addition, the analysis revealed that better muscle function before surgery made it more likely that a patient would undergo a DIEP-flap-reconstruction successfully. Patient age also had a highly significant effect on muscle recovery (p < 0.0005).

Conclusions: This prospective study used a dynamic ultrasound evaluation of the abdominal wall and showed that the DIEP-flap significantly reduces donor site morbidity compared to the ms-2-TRAM-flap. The study also showed that good preoperative muscle function might increase the probability of surgeons performing a DIEP-flap reconstruction.

Keywords: Abdominal wall study; Breast reconstruction; DIEP flap; Donor site morbidity; TRAM flap.