Feasibility of Endoscopic Inspection of Pedicle Wall Integrity in a Live Surgery Model

Abstract

Background: Perforations of the pedicle wall during cannulation can occur with experienced surgeons. Direct endoscopic visualization has not been used to inspect pedicles previously due to bone bleeding obscuring the camera visualization. The hypothesis of this study was that endoscopic visualization of pedicle wall integrity was technically feasible and would enable identification of clinically significant pedicle breaches.Methods: A live porcine model was used. Eight lumbar pedicles were cannulated. Clinically significant breaches were created. An endoscope was introduced and was used to inspect the pedicles.Results: All lumbar pedicles were endoscopically visible at a systolic pressure of 100 mm Hg. Clinically relevant anatomic structures and iatrogenic pathology, such as medial, lateral, and anterior breaches, were identified. There were no untoward events resulting from endoscopic inspection of the pedicle endosteal canal.Conclusions: Endoscopic inspection of lumbar pedicles was safe and effective. The findings on endoscopic inspection corresponded with the ball-tip probe palpation techniques. Additional techniques, such as selection between 2 tracts, was possible with the endoscopic technique.

Feasibility and accuracy of intraosseous endoscopy for inspection of thoracolumbar and lumbar pedicle drill tracts in a canine large-breed cadaveric model

“…Stauber and Bassett 16 described successful endoscopic examination of lumbar pedicle drill tracts in 3 adult sheep, whereas Frank and Chamberland 15 reported successful cannulation of 22 pedicle tracts in 2 human cadaveric specimens. An important difference between the vertebral specimens used in previous studies 14,16 and those used in our study is the size of the vertebral drill tracts, and therefore the feasibility of intraosseous endoscopy remained unknown in the canine spine. For instance, in the study by Stauber and Bassett, 16 5-mm pedicle drill tracts were created to accommodate a 3-mm scope within a 4.25-mm diameter cannula, whereas in the study by Radcliff et al, 14 although the specific size of the drill tracts is not stated, they were large enough to accommodate a 3-mm endoscope in combination with a ball-tipped probe.…”

“…An important difference between the vertebral specimens used in previous studies 14,16 and those used in our study is the size of the vertebral drill tracts, and therefore the feasibility of intraosseous endoscopy remained unknown in the canine spine. For instance, in the study by Stauber and Bassett, 16 5-mm pedicle drill tracts were created to accommodate a 3-mm scope within a 4.25-mm diameter cannula, whereas in the study by Radcliff et al, 14 although the specific size of the drill tracts is not stated, they were large enough to accommodate a 3-mm endoscope in combination with a ball-tipped probe. The size of the arthroscopes used in previous studies varied from 1.2 mm to 3 mm.…”

“…This was based on the results of 3 previous studies in which intraosseous endoscopy of porcine, ovine, and human pedicle tracts was successfully performed. [14][15][16] In a study by Radcliff et al, 14 intraosseous endoscopy of 8 lumbar pedicles was successfully carried out in an 82-kg adult pig using a 0-degree and 30-degree arthroscope. Stauber and Bassett 16 described successful endoscopic examination of lumbar pedicle drill tracts in 3 adult sheep, whereas Frank and Chamberland 15 reported successful cannulation of 22 pedicle tracts in 2 human cadaveric specimens.…”

“…Radcliff et al 14 demonstrated the feasibility of endoscopic inspection of pedicle drill tracts in an experimental live porcine model and its ability to successfully identify iatrogenic medial, lateral, and anterior lumbar breaches. No specialized pumps or pressure bags were required, with saline irrigation allowed to flow at gravity pressure.…”

“…No specialized pumps or pressure bags were required, with saline irrigation allowed to flow at gravity pressure. 14 Frank and Chamberland 15 described the use of a 1.2-mm endoscope adapted to fit within a hollow pedicle probe, with irrigation provided via a separate channel within the endoscope. This device was used to probe 36 sawbones and 22 human cadaveric thoracolumbar pedicles; however, a limitation of that study is that no breaches were created in the cadaveric specimens, and therefore its ability to detect breach was not evaluated.…”