The period of post-operative treatment before surgical wounds
are completely closed remains a key window, during which one can
apply new technologies that can minimise complications. One such
technology is the use of negative pressure wound therapy to manage
and accelerate healing of the closed incisional wound (incisional
NPWT). We undertook a literature review of this emerging indication
to identify evidence within orthopaedic surgery and other surgical
disciplines. Literature that supports our current understanding
of the mechanisms of action was also reviewed in detail. Objectives
Methods
We have developed an animal model to examine the formation of heterotopic ossification using standardised muscular damage and implantation of a beta-tricalcium phosphate block into a hip capsulotomy wound in Wistar rats. The aim was to investigate how cells originating from drilled femoral canals and damaged muscles influence the formation of heterotopic bone. The femoral canal was either drilled or left untouched and a tricalcium phosphate block, immersed either in saline or a rhBMP-2 solution, was implanted. These implants were removed at three and 21 days after the operation and examined histologically, histomorphometrically and immunohistochemically. Bone formation was seen in all implants in rhBMP-2-immersed, whereas in those immersed in saline the process was minimal, irrespective of drilling of the femoral canals. Bone mineralisation was somewhat greater in the absence of drilling with a mean mineralised volume to mean total volume of 18.2% ( Our findings suggest that osteoinductive signalling is an early event in the formation of ectopic bone. If applicable to man the results indicate that careful tissue handling is more important than the prevention of the dissemination of bone cells in order to avoid heterotopic ossification.
