Acute and chronic effects of motorised dental burr assisted thoracic spinal laminectomy on the functionality and welfare of the contusion spinal cord injury rat model

This study focused on acute and chronic effects of the recently established Dental Burr Assisted (DBA) technique to perform laminectomy at T10-T11 vertebral level in a rat model of spinal cord injury (SCI)on animal welfare as well as functionality, and compared it to the conventional technique. The utility as a model of chronic pain, and the effects of SCI on memory was also assessed, using DBA technique and was compared to conventional technique of laminectomy. A total of 24 Crl:WI female rats were assigned randomly to four equal groups- conventionally laminectomised, dental burr assisted laminectomised, conventionally laminectomised with spinal cord contusion and dental burr assisted laminectomised with spinal cord contusion injuries. In a 56 day long study, the animals were tested for bleeding during surgery; Basso Beattie and Bresnahan (BBB) score; body weight changes; Rat Grimace Scale (RGS); light phase open field activity; dark phase home cage activity; sucrose preference as an indicator for hedonistic behaviour; novel object recognition to assess short and long term memory during acute and chronic stages; mechanical allodynia using von Frey filaments; and detailed histopathology of the spinal cord to estimate surviving neuronal number and area of vacuoles at the end of the study. The results indicate that the analgesia provided during post-operative phase did not affect the outcome of the chronic pain model and that, DBA technique can be a functional alternative to the conventional technique to achieve better welfare without affecting the functionality and research outcome in SCI injury studies.