PT  - JOURNAL ARTICLE
AU  - de Andrada Pereira, Bernardo
AU  - O’Neill, Luke K.
AU  - Sawa, Anna G.U.
AU  - Zhou, James J.
AU  - Wangsawatwong, Piyanat
AU  - Lehrman, Jennifer N.
AU  - Godzik, Jakub
AU  - Oldham, Alton J.
AU  - Turner, Jay D.
AU  - Kelly, Brian P.
AU  - Uribe, Juan S.
TI  - Biomechanical Assessment of a Novel Sharp-Tipped Screw for 1-Step Minimally Invasive Pedicle Screw Placement Under Navigation
AID  - 10.14444/8470
DP  - 2023 Aug 01
TA  - International Journal of Spine Surgery
PG  - 484--491
VI  - 17
IP  - 4
4099  - https://www.ijssurgery.com/content/17/4/484.short
4100  - https://www.ijssurgery.com/content/17/4/484.full
SO  - Int J Spine Surg2023 Aug 01; 17
AB  - Background The objective of this study was to assess the pullout force of a novel sharp-tipped screw developed for single-step, minimally invasive pedicle screw placement guided by neuronavigation compared with the pullout force for traditional screws.Methods A total of 60 human cadaveric lumbar pedicles were studied. Three different screw insertion techniques were compared: (A) Jamshidi needle and Kirschner wire without tapping; (B) Jamshidi needle and Kirschner wire with tapping; and (C) sharp-tipped screw insertion. Pullout tests were performed at a displacement rate of 10 mm/min recorded at 20 Hz. Mean values of these parameters were compared using paired t tests (left vs right in the same specimen): A vs B, A vs C, and B vs C. Additionally, 3 L1-L5 spine models were used for timing each screw insertion technique for a total of 10 screw insertions for each technique. Insertion times were compared using 1-way analysis of variance.Results The mean pullout force for insertion technique A was 1462.3 (597.5) N; for technique B, it was 1693.5 (805.0) N; and for technique C, it was 1319.0 (735.7) N. There was no statistically significant difference in pullout force between techniques (P > 0.08). The average insertion time for condition C was significantly less than that for conditions A and B (P < 0.001).Conclusions The pullout force of the novel sharp-tipped screw placement technique is equivalent to that of traditional techniques. The sharp-tipped screw placement technique appears biomechanically viable and has the advantage of saving time during insertion.Clinical Relevance Single-step screw placement using high resolution 3-dimensional navigation has the potential to streamline workflow and reduce operative time.Level of Evidence 5.