Introduction and Aims: Incidental dural tears and cerebrospinal fluid (CSF) leaks are common complications of spinal surgery. Collagen matrix (DuraGen, Integra LifeSciences) derived from bovine flexor tendons allows CSF absorption up to 100 times its weight without a volume change. Aim of this study was categorising the dural tears and monitoring post-operative complications. Method: In this three-year prospective study, 35 patients (22 males, 13 females; mean age 53.8 years (range 16–82)) were selected by the following criteria: (1) any spine operation resulting in intra-operative CSF leak due to dural tear; or (2) persistent post-operative CSF leak. Collagen matrix was cut according to the extent of the dural defect (pinhole, < 1cm, 1–2 cm, and > 2cm). Dural matrix was moistened and applied as a graft and overlying tissues were meticulously reconstituted. Collagen sponge was not sutured on the dura. Subfascial drain was used at the discretion of surgeon to avoid hematoma and blood loss. Results: The 39 procedures were as follows: 23 laminectomies, six diskectomies, four hematoma repairs, three structural repairs, two fracture stabilisations and one cystectomy. The locations of the 39 procedures were: 27 lumbar, seven thoracic, and five cervical. In 33 of 39 procedures, hemovac subfascial drain was used to avoid hematoma and excessive blood loss. Fibrin glue was used in two cases only. In 13 cases the dural defect was > 2cm, five cases 1–2cm, five cases < 2cm, and nine were pinhole defects. Of importance was the successful repair of 13 large dural tears (> 2cm) using the collagen sponge. Our study showed a 97.4% success rate for repairing dural tears using the collagen sponge surpassing the established techniques success rates by up to 10%. There were no wound infections post-operatively, versus the 6% rate of deep wound infection using the standard suture and fibrin glue. The mean follow-up time was 3.1 months. In two out of 39 procedures collagen sponge was used to repair persistent post-operative CSF leaks (no dural sponge used in the original operation). Conclusion: Considering the technical challenge of dural tears, especially ventral or lateral tears, the use of collagen sponge offers an excellent alternative mini-mising a prolonged procedure, wound infection, use of tissue grafts, as well as excessive blood loss. This study showed collagen sponge to be effective as a permanent dural substitute

Objective

A clinical investigation into a new bone void filler is giving first data on systemic and local exposure to the anti-infective substance after implantation.