Commercial suture passer improves efficiency and ease of use versus conventional needle in minimally invasive thoracolumbar fascia closure: a cadaveric analysis.

Background: Low-profile suture passers have been introduced to facilitate thoracolumbar fascia closure in minimally invasive spine (MIS) surgery. The purpose of this study was to evaluate the closure time of a modern suture passer to a conventional curved need for MIS fascia closure in a cadaveric model. Methods: Six clinicians specializing in orthopedic spine surgery were recruited for the study and randomly assigned 1 cadaveric torso. Subcutaneous tissue was resected at L4-L5, replicating MIS surgery, followed by placement of a 60×18-mm or 100×18-mm tubular retractor for access. Clinicians were required to close the fascia with three unknotted, simple interrupted sutures using a swaged curved needle or suture passer (Spine Scorpion™, Arthrex, Inc., Naples, FL). The completion time was recorded, starting immediately before suturing and ending after the last pass. A time cutoff of 10 min was implemented in consideration of reasonable operating room time, and the number of achieved suture passes (of 6) were recorded. Clinicians were asked to qualitatively grade ease of use in relation to prior fascial closure experience per a 0-5 scale, where 0 is impossible and 5 is easiest. Results: The mean change in fascial closure completion time (Δ) was significantly reduced with the Spine Scorpion compared to the curved needle with the 60×18-mm retractor (Δ=5.80 min; 95% CI, 2.92-8.67 min; p=.004) and 100 × 18-mm retractor (Δ=5.28 min; 95% CI, 2.76-7.80 min; p=.003). Full closure was achieved within the time limit for all trials of the Spine Scorpion, while the standard needle achieved full closure in 67% (4 of 6) and 50% (3 of 6) of trials with the 60 × 18-mm and 100×18-mm retractors, respectively. Median ease-of-use scores with the 60×18-mm and 100×18-mm retractors, respectively, were 4.5 (range, 4-5) and 4.5 (range, 3-5) for the Spine Scorpion, and both 1.0 (range, 1-2) for the curved needle. Conclusion: Results from this laboratory investigation using a suture passer for thoracolumbar fascia closure show a significant reduction in closure time and completion of the procedure compared to a conventional curved needle.

Tape-Reinforced Graft Suturing and Retensioning of Adjustable-Loop Cortical Buttons Improve Quadriceps Tendon Autograft Biomechanics in Anterior Cruciate Ligament Reconstruction: A Cadaveric Study.

PURPOSE: To investigate the biomechanical effects of tape-reinforced graft suturing and graft retensioning for all-soft tissue quadriceps tendon (ASTQT) anterior cruciate ligament reconstruction (ACLR) in a full-construct human cadaveric model. METHODS: Harvested cadaveric ASTQT grafts were assigned to either (1) double-suspensory adjustable-loop cortical button device (ALD) fixation in which both graft ends were fixed with a suspensory fixation device with (n = 5) or without (n = 5) tape-reinforced suturing or (2) single-suspensory distal tendon fixation in which only the patellar end was fixed with an ALD (n = 5) or fixed-loop cortical button device (FLD) (n = 5). All specimens were prepared using a No. 2 whipstitch technique, and tape-reinforced specimens had an integrated braided tape implant. Graft preparation time was recorded for double-suspensory constructs. Samples were tested on an electromechanical testing machine using a previously published protocol simulating rehabilitative kinematics and loading. RESULTS: Tape-reinforced graft suturing resulted in greater graft load retention after cycling (11.9% difference, P = .021), less total elongation (mean [95% confidence interval (CI)], 5.57 mm [3.50-7.65 mm] vs 32.14 mm [25.38-38.90 mm]; P < .001), greater ultimate failure stiffness (mean [95% CI], 171.9 N/mm [158.8-185.0 N/mm] vs 119.4 N/mm [108.7-130.0 N/mm]; P < .001), and less graft preparation time (36.4% difference, P < .001) when compared with unreinforced specimens. Retensioned ALD constructs had less cyclic elongation compared with FLD constructs (mean total elongation [95% CI], 7.04 mm [5.47-8.61 mm] vs 12.96 mm [8.67-17.26 mm]; P = .004). CONCLUSIONS: Tape-reinforced graft suturing improves time-zero ASTQT ACLR construct biomechanics in a cadaveric model with 83% less total elongation, 44% greater stiffness, and reduced preparation time compared with a whipstitched graft without tape reinforcement. ALD fixation improves construct mechanics when compared with FLD fixation as evidenced by 46% less total elongation. CLINICAL RELEVANCE: Tape-reinforced implants and graft retensioning using ALDs improve time-zero ACLR graft construct biomechanics in a time-zero biomechanical model. Clinical studies will be necessary to determine whether these implants improve clinical outcomes including knee laxity and the incidence of graft rupture.

Biomechanical comparison of canine median sternotomy closure using suture tape and orthopedic wire cerclage.

OBJECTIVE: To compare the mechanical properties of suture tape and orthopedic wire cerclage in an ex vivo canine median sternotomy model. STUDY DESIGN: Ex vivo. ANIMALS: Twelve large-breed canine cadaveric sternums. METHODS: Median sternotomies were performed, leaving the manubrium intact. The specimens were randomly assigned to group W (20-gauge stainless steel orthopedic wire cerclage in a figure-of-eight pattern) or group ST (suture tape in a figure-of-eight pattern). Each specimen was laterally distracted until failure using an electrodynamic materials-testing system. RESULTS: No differences were observed for displacement, yield load, maximum load, implant failure between the groups. The orthopedic wire construct was stiffer than the suture tape construct. CONCLUSION: Suture tape was biomechanically similar to orthopedic wire cerclage for sternotomy closure in dogs, although wire constructs were stiffer. CLINICAL SIGNIFICANCE: Suture tape may represent an alternative to cerclage wire for sternotomy closure in dogs. Additional studies evaluating its clinical use are needed.

Expression of hypoxia inducible factor-1α and vascular endothelia growth factor in vocal polyps.

OBJECTIVES/HYPOTHESIS: Long-term vocal overuse or sudden vocal-fold microvascular disruption may lead to the formation of a hypoxic zone of injury and the subsequent release of a cascade of cytokines in the vocal fold. To test this hypothesis, we investigated the expression and the role of hypoxia inducible factor-1α (HIF-1α) and vascular endothelia growth factor (VEGF) in the formation of vocal polyps. METHODS: Expression patterns of HIF-1α and VEGF in surgical specimens of vocal polyps from 36 patients were analyzed using the immunohistochemistry and Western blot method. Normal vocal-fold mucosa from 26 patients who underwent total laryngectomy were collected and used as the control group. RESULTS: The expression of HIF-1α and VEGF were detected both in the vocal polyps group and the control group, while the expression of HIF-1α and VEGF levels were significantly higher when compared to normal vocal-fold mucosa (P < .05). CONCLUSION: The increased expression of HIF-1α in vocal polyps indicates that vocal fold overvibration induced hypoxia may play an important role in the pathogenetic mechanism of vocal polyps.

Study of the head and neck position in microlaryngoscopy using magnetic resonance imaging.

Several studies have critically analyzed the ideal position for laryngeal exposure during microlaryngoscopy; however, these studies have lacked the ability to evaluate the head and neck position while maintaining a direct view into the airway. Therefore, a newly established two-curve methodology was used to investigate the influence of head and neck position during microlaryngoscopy in MRI images. Fourteen normal adult volunteers were used in this magnetic resonance imaging study. The airway was divided into two curves in the sagittal plane at the center of the airway in three head and neck positions: extension-extension, neutral and flexion-extension position. The airway passage curves, point of inflection and its tangent, the line of laryngoscope, line of hyoid bone and mandible were plotted on each scan. Angles and area formed by these lines were calculated to evaluate the airway morphology changes. The flexion-extension position caused a reduction in the area between the line of laryngoscope and curves, but there was no significant difference between the three positions (p = 0.664). The flexion-extension position also resulted in the lowest angle values for α (angle between the tangent and horizon, p = 0.000), ß (between the line of hyoid and horizon, p = 0.002) and δ (between the line of mandible and horizon, p = 0.004). Our study provides a better understanding of the changes in normal airway morphology during microlaryngoscopy in different positions, reinforcing the concept that flexion-extension position is the optimal position for microlaryngoscopy.