Alexander A Theologis1, Shane Burch. 1. From the Department of Orthopaedic Surgery, University of California, San Francisco, San Francisco, CA.
Abstract
STUDY DESIGN: Retrospective analysis. OBJECTIVE: To determine safety and efficacy of cervical pedicle screw placement using O-Arm and Stealth Navigation in patients with cervicothoracic spinal deformities and revision subaxial cervical pathology. SUMMARY OF BACKGROUND DATA: Cervical pedicle screws are biomechanically advantageous to other posterior cervical fixation techniques; however, their use is limited by concerns for neurovascular injury. Few clinical reports exist on their placement safety and efficacy using modern navigation systems. METHODS: Adults who had cervical pedicle screws inserted using O-Arm and Stealth Navigation between November 2007 and January 2014 and with a minimum 1-year follow-up were retrospectively studied. Screw insertion safety, surgical complications, need for reoperation, and clinical outcomes [Neck Disability Index, EQ-5D, numeric pain rating scales] were evaluated. RESULTS: 21 patients (female-10; male-11; average age 63 yr [32-83 yr]) met inclusion criteria. Average follow-up was 29.8 months (12-81.6 mo). Reconstruction of C2 and the subaxial cervical spine included 8 primary operations for cervicothoracic kyphosis and 13 revision operations. 121 pedicle screws were placed (C2: 4, C3: 20, C4: 22, C5: 23, C6: 18, C7: 34) using Stealth Navigation. The average number of screws placed per case was 6 (1-12). Greater than 99% of screws were placed safely without neurovascular injury. 1 screw (0.8%) was noted postoperatively to critically breach the medial wall and was associated with an acute C5 nerve root palsy. 2 patients required revisions for postoperative iatrogenic foraminal stenosis and associated C8 radiculopathies. No vascular complications due to aberrant screw placement occurred. There were significant improvements (P < 0.05) in EQ-5D utility scores and neck and arm pain. Neck Disability Index scores decreased on average by 10 points (P = 0.12). CONCLUSION: Placement of cervical pedicle screws using O-Arm/Stealth Navigation in this series was a safe and effective method for posterior stabilization in cervicothoracic deformity and revision operations of the subaxial cervical spine. LEVEL OF EVIDENCE: 4.
STUDY DESIGN: Retrospective analysis. OBJECTIVE: To determine safety and efficacy of cervical pedicle screw placement using O-Arm and Stealth Navigation in patients with cervicothoracic spinal deformities and revision subaxial cervical pathology. SUMMARY OF BACKGROUND DATA: Cervical pedicle screws are biomechanically advantageous to other posterior cervical fixation techniques; however, their use is limited by concerns for neurovascular injury. Few clinical reports exist on their placement safety and efficacy using modern navigation systems. METHODS: Adults who had cervical pedicle screws inserted using O-Arm and Stealth Navigation between November 2007 and January 2014 and with a minimum 1-year follow-up were retrospectively studied. Screw insertion safety, surgical complications, need for reoperation, and clinical outcomes [Neck Disability Index, EQ-5D, numeric pain rating scales] were evaluated. RESULTS: 21 patients (female-10; male-11; average age 63 yr [32-83 yr]) met inclusion criteria. Average follow-up was 29.8 months (12-81.6 mo). Reconstruction of C2 and the subaxial cervical spine included 8 primary operations for cervicothoracic kyphosis and 13 revision operations. 121 pedicle screws were placed (C2: 4, C3: 20, C4: 22, C5: 23, C6: 18, C7: 34) using Stealth Navigation. The average number of screws placed per case was 6 (1-12). Greater than 99% of screws were placed safely without neurovascular injury. 1 screw (0.8%) was noted postoperatively to critically breach the medial wall and was associated with an acute C5 nerve root palsy. 2 patients required revisions for postoperative iatrogenic foraminal stenosis and associated C8 radiculopathies. No vascular complications due to aberrant screw placement occurred. There were significant improvements (P < 0.05) in EQ-5D utility scores and neck and arm pain. Neck Disability Index scores decreased on average by 10 points (P = 0.12). CONCLUSION: Placement of cervical pedicle screws using O-Arm/Stealth Navigation in this series was a safe and effective method for posterior stabilization in cervicothoracic deformity and revision operations of the subaxial cervical spine. LEVEL OF EVIDENCE: 4.