Biomechanical proof of barbed sutures for the efficacy of laparoscopic pyeloplasty

The gold standard for management of adult ureteropelvic junction obstruction is laparoscopic dismembered pyeloplasty (LPP), described by Anderson-Hynes, with reduced postoperative complications, early patient release, and favorable results. LPP, however, necessitates a high level of surgical expertise, especially with regard to reanastomosis. Knotless self-anchoring barbed sutures have also been introduced into aesthetic surgery and wound closure. We compared a self-retaining suture (SRS) Quill(®) (Angiotech, Canada) with a standard monofilament suture to further investigate their biomechanical and urodynamic aspects.

We analyzed breaking strength and stiffness between SRS 4.0, 3.0, and polydioxanone suture (PDS(®)) 4.0 (Ethicon, Germany) using a biomechanical testing unit. Urodynamic evaluations were performed in the porcine upper urinary tract, closing a longitudinal incision either with SRS 4.0 (without knots) or with PDS 4.0 (five knots each end). Suture line shortening, suture time, tightness, and intrapelvic pressure were measured.

SRS 4.0 breaks at a mean of 11.57 N (standard deviation [SD]=1.25, stiffness 172.8 N/mm(2), SD=10.84), SRS 3.0 at 16.01 N (1.81), and PDS 4.0 at 18.41 N (0.75, 128.9 N/mm(2), 7.45). SRS 4.0 results in a suture line shortening from mean 3.08 to 2.26 mm (-26.6%) while PDS 4.0 shortens from 3.05 to 1.81 mm (-40.7%). The maximum intrapelvic pressure demonstrated no difference, and leakage was seen in 50% of the cases. Suture time was significantly decreased with SRS use (SRS 4.0 277 s and PDS 4.0 364 s).

SRS offers immediate tissue adaption with reduced suture line shortening and equal tightness compared with nonbarbed material in vitro. Knotless suturing using SRS is time efficient and appears to be an excellent material for LPP.