Hanlon J, Hudson CC, Litsky AS, Jones SC. Mechanical evaluation of canine sacroiliac joint stabilization using two short screws.
Vet Surg 2022;
51:1061-1069. [PMID:
35929727 PMCID:
PMC9804304 DOI:
10.1111/vsu.13857]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 05/11/2022] [Accepted: 06/18/2022] [Indexed: 01/05/2023]
Abstract
OBJECTIVE
To assess the feasibility and mechanical stability of sacroiliac (SI) joint stabilization using 2 short 3.5 mm cortical screws, each spanning an average of 23% of the width of the sacral body.
STUDY DESIGN
Cadaveric experimental study.
SAMPLE POPULATION
Twenty-four canine pelvis specimens.
METHODS
Pelvis specimens were prepared by disarticulation of the left SI joint and osteotomy of the left pubis and left ischium, and stabilized using a single long lag screw (LLS), 2 short lag screws (SLS) or 2 short positional screws (SPS). Computed tomography (CT) imaging was used to determine standardized screw lengths for each group and was repeated following implant insertion. Specimens were secured within a servohydraulic test frame and loaded through the acetabulum to simulate weight bearing under displacement control at 4 mm/min for 20 mm total displacement. Group mechanical testing data were compared.
RESULTS
Peak load, yield load, and stiffness were more than 2 times greater in both the SLS and SPS groups when compared with the LLS group. No mechanical difference was identified between the short-screw groups.
CONCLUSION
Sacroiliac luxation fixation using 2 short screws created a stronger, stiffer construct when compared with fixation using a single lag screw spanning 60% of the width of the sacral body. No mechanical advantage was observed between short screws inserted in positional vs. lag fashion.
CLINICAL SIGNIFICANCE
Sacroiliac luxation fixation using 2 short screws creates a mechanically superior construct with a larger region of acceptable implant positioning and potentially reduced risk of iatrogenic injury compared with conventional fixation.
Collapse