Background Matrices are now commonly used in breast reconstruction, but the scientific evidence is still scares. The main aim was to compare complications and the need for corrections in immediate breast reconstruction with the porcine-derived Surgisis ® with the traditional muscle-covered technique. The secondary aim was to compare long-term quality of life and satisfaction. Methods All consecutive patients who had their breast reconstructed with a Surgisis ® or muscle-covered tissue expander/implant were included. Patients were followed clinically and with BREAST-Q. Results During the study period, 116 reconstructions (71 patients) were operated in the Surgisis ® group and 132 reconstructions (90 patients) in the control group. The median follow-up time was 74 months (min 43-max 162). The total early complication rate was 37% in the Surgisis ® group and 27% in the control group. There were no differences in implant loss (p = 0.68) or total number of complications (p = 0.24) between the two groups. Risk factors for complications were mainly patient characteristics and the use of a tissue expander. There was a slightly higher capsular contracture frequency in the Surgisis ® patients (4.2% vs. 2.5%). The need for corrections and patient satisfaction and quality of life were similar in the two groups. Conclusions The use of Surgisis ® in implant-based reconstruction seems to result in an acceptable total early complication rate. The rate might be higher in tissue expander-based reconstruction. Risk factors are mainly patient characteristics. The capsular contracture rate and need for corrections, as well as patient satisfaction and quality of life, are similar in the Surgisis ® patients and muscle-covered controls. Level of evidence: III

Avhandlingen baseras på följande delarbeten I.Maltese G, Fischer S, Strandell A, Tarnow P, Kölby L. Spring-assisted surgery in the treatment of sagittal synostosis: A systematic review.