Dural injury following elective spine surgery - A prospective analysis of risk factors, management and complications.

Incidental dural tears being a familiar complication in spine surgery could result in dreaded postoperative outcomes. Though the literature pertaining to their incidence and management is vast, it is limited by the retrospective study designs and smaller case series. Hence, we performed a prospective study in our institute to determine the incidence, surgical risk factors, complications and surgical outcomes in patients with unintended durotomy during spine surgery over a period of one year. The overall incidence in our study was 2.3% (44/1912). Revision spine surgeries in particular had a higher incidence of 16.6%. The average age of the study population was 51.6 years. The most common intraoperative surgical step associated with dural tear was removal of the lamina, and 50% of the injuries were during usage of kerrison rongeur. The most common location of the tear was paramedian location (20 patients) and the most common size of the tear was about 1 mm-5mm (31 patients). We observed that the dural repair techniques, placement of drain and prolonged post-operative bed rest didnot significantly affect the post-operative outcomes. One patient in our study developed persistent CSF leak, which was treated by subarachnoid lumbar drain placement. No patients developed pseudomeningocele or post-operative neurological worsening or re-exploration for dural repair. Wound complications were noted in 4 patients and treated by debridement and antibiotics. Based on our study, we have proposed a treatment algorithm for the management of dural tears in spine surgery.

Risk factors for thirty-day morbidity and mortality after spinal trauma.

BACKGROUND: Traumatic Spinal Injuries (TSI) often follow high velocity injuries and frequently accompanied by polytrauma. While most studies have focussed on outcomes of spinal cord injuries, the incidence and risk factors that predict morbidity and mortality after TSI has not been well-defined. METHODS: Data of consecutive patients of TSI (n = 2065) treated over a 5-year-period were evaluated for demographics, injury mechanisms, neurological status, associated injuries, timing of surgery and co-morbidities. The thirty-day incidence and risk factors for complications, length of stay and mortality were analysed. RESULTS: The incidence of spinal trauma was 6.2%. Associated injuries were seen in 49.7% (n = 1028), and 33.5% (n = 692) patients had comorbidities. The 30-day mortality was 0.73% (n = 15). Associated chest injuries (p = 0.0001), cervical spine injury (p = 0.0001), ASIA-A neurology (p < 0.01) and ankylosing spondylitis (p = 0.01) correlated with higher mortality. Peri-operative morbidity was noted in 571 patients (27.7%) and were significantly associated with age > 60 (p = 0.043), ASIA-A neurology (p < 0.05), chest injuries (p = 0.042), cervical and thoracic spine injury (p < 0.0001). The mean length of stay in hospital was 8.87 days. Cervical spine injury (p < 0.0001), delay in surgery > 48 h (p = 0.011), Diabetes mellitus (p = 0.01), Ankylosing spondylitis (p = 0.009), associated injuries of chest, head, pelvis and face (p < 0.05) were independent risk factors for longer hospital stay. CONCLUSION: Key predictors of mortality after spinal trauma were cervical spine injury, complete neurological deficit, chest injuries and ankylosing spondylitis, while additionally higher age and thoracic injuries contributed to higher morbidity and prolonged hospitalisation. Notably multi-level injuries, higher age, co-morbidities and timing of surgery did not influence the mortality.

The "Skipped Segment Screw" Construct: An Alternative to Conventional Lateral Mass Fixation-Biomechanical Analysis in a Porcine Cervical Spine Model.

STUDY DESIGN: Cadaveric biomechanical study. PURPOSE: We compared the "skipped segment screw" (SSS) construct with the conventional "all segment screw" (ASS) construct for cervical spine fixation in six degrees of freedom in terms of the range of motion (ROM). OVERVIEW OF LITERATURE: Currently, no clear guidelines are available in the literature for the configuration of lateral mass (LM) screwrod fixation for cervical spine stabilization. Most surgeons tend to insert screws bilaterally at all segments from C3 to C6 with the assumption that implants at every level will provide maximum stability. METHODS: Six porcine cervical spine specimens were harvested from fresh 6-9-month-old pigs. Each specimen was sequentially tested in the following order: intact uninstrumented (UIS), SSS (LM screws in C3, C5, and C7 bilaterally), and ASS (LM screws in C3-C7 bilaterally). Biomechanical testing was performed with a force of 2 Nm in six degrees of freedom and 3D motion tracking was performed. RESULTS: The two-tailed paired t-test was used for statistical analysis. There was a significant decrease in ROM in instrumented specimens compared with that in UIS specimens in all six degrees of motion (p<0.05), whereas there was no significant difference in ROM between the different types of constructs (SSS and ASS). CONCLUSIONS: Because both configurations provide comparable stability under physiological loading, we provide a biomechanical basis for the use of SSS configuration owing to its potential clinical advantages, such as relatively less bulk of implants within a small operative field, relative ease of manipulating the rod into position, shorter surgical time, less blood loss, lower risk of screw-related complications, less implant-related costs, and most importantly, no compromise in the required stability needed until fusion.