The changing epidemiology of traumatic spine injuries: a trends analysis of 26 years of patients at a major level 1 trauma center in the United States.

BACKGROUND CONTEXT: Traumatic spinal injuries (TSI) are associated with high morbidity, mortality, and resource utilization. The epidemiology of TSI varies greatly across different countries and regions and is impacted by national income levels, infrastructure, and cultural factors. Further, there may be changes over time. It is essential to investigate TSI to gain useful epidemiologic information. However, there have been no recent studies on trends for TSI in the US, despite the changing population demographics, healthcare policy, and technology. As a result, reexamination is warranted to reflect how the modern era has affected the epidemiology of US spine trauma patients and their management. PURPOSE: To determine epidemiologic trends in traumatic spine injuries over time. STUDY DESIGN/SETTING: Retrospective analysis; level 1 trauma center in the United States. PATIENT SAMPLE: A total of 21,811 patients, between the years of 1996 and 2022, who presented with traumatic spine injury. OUTCOME MEASURES: Age, sex, race, Injury Severity Score, mechanism of injury, injury diagnosis, injury level, rate of operative intervention, hospital length of stay, intensive care unit length of stay, discharge disposition, in-hospital mortality. METHODS: Data was collected from our institutional trauma registry over a 26-year period. Inclusion criteria involved at least one diagnosis of vertebral fracture, spinal cord injury, spinal subluxation, or intervertebral disc injury. Exclusion criteria consisted of patients with no diagnosed spine injury or a diagnosis of strain only. A total of 21,811 patients were included in the analysis. Descriptive statistics were tabulated and ordinary least squares linear regression was conducted for trends analysis. RESULTS: Regression analysis showed a significant upward trend in patient age (+13.83 years, ß=+0.65/year, p<.001), female sex (+2.7%, ß=+0.18%/year, p=.004), falls (+10.5%, ß=+0.82%/year, p<.001), subluxations (+12.8%, ß=+0.35%/year, p<.001), thoracic injuries (+1.5%, ß=+0.28%/year, p<.001), and discharges to subacute rehab (+15.9%, ß=+0.68%/year, p<.001). There was a significant downward trend in motor vehicle crashes (-7.8%, ß=-0.47%/year, p=.016), firearms injuries (-3.4%, ß=-0.19%/year, p<.001), sports/recreation injuries (-2.9%, ß=-0.18%/year, p<.001), spinal cord injuries (-11.25%, ß=-0.37%, p<.001), complete spinal cord injuries (-7.6%, ß=-0.24%/year, p<.001), and discharges to home (+4.5%, ß=-0.27%/year, p=.011). CONCLUSIONS: At our institution, the average spine trauma patient has trended toward older females. Falls represent an increasing proportion of the mechanism of injury, on a trajectory to become the most common cause. With time, there have been fewer spinal cord injuries and a lower proportion of complete injuries. At discharge, there has been a surge in the utilization of subacute rehabilitation facilities. Overall, there has been no significant change in injury severity, rate of operative intervention, length of stay, or mortality.

Intramedullary nailing of extra-articular distal tibial fractures.

AIMS: The aim of this study was to determine the immediate post-fixation stability of a distal tibial fracture fixed with an intramedullary nail using a biomechanical model. This was used as a surrogate for immediate weight-bearing postoperatively. The goal was to help inform postoperative protocols. METHODS: A biomechanical model of distal metaphyseal tibial fractures was created using a fourth-generation composite bone model. Three fracture patterns were tested: spiral, oblique, and multifragmented. Each fracture extended to within 4 cm to 5 cm of the plafond. The models were nearly-anatomically reduced and stabilized with an intramedullary nail and three distal locking screws. Cyclic loading was performed to simulate normal gait. Loading was completed in compression at 3,000 N at 1 Hz for a total of 70,000 cycles. Displacement (shortening, coronal and sagittal angulation) was measured at regular intervals. RESULTS: The spiral and oblique fracture patterns withstood simulated weight-bearing with minimal displacement. The multifragmented model had early implant failure with breaking of the distal locking screws. The spiral fracture model shortened by a mean of 0.3 mm (SD 0.2), and developed a mean coronal angulation of 2.0° (SD 1.9°) and a mean sagittal angulation of 1.2° (SD 1.1°). On average, 88% of the shortening, 74% of the change in coronal alignment, and 75% of the change in sagittal alignment occurred in the first 2,500 cycles. No late acceleration of displacement was noted. The oblique fracture model shortened by a mean of 0.2 mm (SD 0.1) and developed a mean coronal angulation of 2.4° (SD 1.6°) and a mean sagittal angulation of 2.6° (SD 1.4°). On average, 44% of the shortening, 39% of the change in coronal alignment, and 79% of the change in sagittal alignment occurred in the first 2,500 cycles. No late acceleration of displacement was noted. CONCLUSION: For spiral and oblique fracture patterns, simulated weight-bearing resulted in a clinically acceptable degree of displacement. Most displacement occurred early in the test period, and the rate of displacement decreased over time. Based on this model, we offer evidence that early weight-bearing appears safe for well reduced oblique and spiral fractures, but not in multifragmented patterns that have poor bone contact. Cite this article: Bone Joint J 2021;103-B(2):294-298.

Motion and Strength Analysis of 2-Tine Staple and K-Wire Fixation in Scapholunate Ligament Stabilization in a Cadaver Model.

Purpose: Previous studies have demonstrated the benefits of 2- and 4-tine staple fixation in scapholunate interosseous ligament (SLIL) reconstruction, including improved rotational control and avoidance of the articular surface. This study compared scaphoid and lunate kinematics after SLIL fixation with traditional Kirschner wire (K-wire) fixation or 2-tine staple fixation. Methods: Eight fresh frozen cadaver arms with normal scapholunate (SL) intervals were included. Infrared motion capture was used to assess kinematics between the scaphoid and lunate as the wrists were moved through a simulated dart-throw motion. Kinematic data were recorded for each wrist in 4 states: SLIL intact, SLIL sectioned, K-wire fixation across SL interval and scaphocapitate joint, and 2-tine Nitinol staple fixation across SL interval. Strength of the SL staple fixation was evaluated using an axial load machine to assess load to failure of the staple construct. Results: Range of motion of the scaphoid and lunate with SLIL intact and SLIL sectioned were similar. K-wire fixation across the SL interval significantly decreased the overall wrist range of motion as well as scaphoid and lunate motion in all planes except for scaphoid flexion. Conversely, scaphoid and lunate motion after staple fixation was similar to that in normal wrists, except for a significant decrease in scaphoid extension. Under axial load simulating a ground-level fall, 3 of 8 arms demonstrated no failure, and none of the failures was due to direct failure of the 2-tine staple. Conclusions: This study demonstrates 2-tine staple fixation across the SL interval is effective in providing initial stability and maintaining physiologic motion of the scaphoid and lunate compared with K-wire fixation after SLIL injury. Clinical relevance: This study demonstrates an alternate technique for the stabilization of the SL interval in repair of acute SLIL injuries using 2-tine staple fixation, which maintains near physiologic motion of the scaphoid and lunate after SLIL injury.