Purpose: To identify factors associated with adjacent-level ossification development (ALOD) after anterior cervical discectomy and fusion (ACDF) and associated clinical outcomes. Methods: We retrospectively reviewed records of 140 adults who underwent primary ACDF for degenerative disc disease. We compared patients with and without ALOD after ACDF. Radiographic measurements and factors associated with ALOD were assessed preoperatively and at minimum 24-month follow-up. Clinical outcomes were incidence of clinical adjacent-segment pathologies (CASP), revision surgery, and patient-reported outcomes. Results: Factors associated with both cranial and caudal ALOD were short plate-to-disc distance (PDD), adjacent-segment kyphosis, hyperlordotic ACDF causing junctional segment kyphosis, and preoperative ossification of the anterior longitudinal ligament (OALL). Mean final adjacent-segment range of motion (ROM) was less in those with cranial ALOD (6.9° ± 2.8°) than in those without cranial ALOD (12° ± 4.2°) (p < 0.01). Mean final adjacent-segment ROM was also less in those with caudal ALOD (5.5° ± 2.4º) than in those without caudal ALOD (8.2º ± 3.7º) (p < 0.01). The incidence of CASP-required surgery was higher in those with caudal ALOD (p = 0.02) but no different in those with cranial ALOD (p = 0.69) compared with those without ALOD. Conclusion Factors associated with ALOD were a kyphotic segment adjacent to ACDF, hyperlordotic fusion, preoperative OALL, and short PDD. ALOD was associated with less segmental ROM and, for those with caudal but not cranial ALOD, higher incidence of revision surgery for CASP.

Endoscopic spine surgery (ESS) is growing in popularity worldwide. An expanding body of literature demonstrates rapid functional recovery with reduced morbidity compared to open techniques. Both full endoscopic spine surgery, or uniportal endoscopy, and unilateral biportal endoscopy (UBE) can be employed in conjunction with various navigation and enabling technologies for assistance with localization of anatomic orientation and assessment of the intraoperative target spinal pathology. This review article describes various navigation technologies in ESS, including 2-dimensional (2D) fluoroscopic imaging, 2D fluoroscopic navigation, 3-dimensional C-arm navigation, augmented reality, and spinal robotics. Employment of enabling navigation and emerging technology with the registration of patient-specific anatomy enables clear delineation of anatomic landmarks and facilitation of a successful procedure. Additionally, avoidance of common pitfalls during use of navigation systems in ESS is discussed in this review.

Purpose: To identify factors associated with adjacent-level ossification development (ALOD) after anterior cervical discectomy and fusion (ACDF) and associated clinical outcomes. Methods: We retrospectively reviewed records of 140 adults who underwent primary ACDF for degenerative disc disease. We compared patients with and without ALOD after ACDF. Radiographic measurements and factors associated with ALOD were assessed preoperatively and at minimum 24-month follow-up. Clinical outcomes were incidence of clinical adjacent-segment pathologies (CASP), revision surgery, and patient-reported outcomes. Results: Factors associated with both cranial and caudal ALOD were short plate-to-disc distance (PDD), adjacent-segment kyphosis, hyperlordotic ACDF causing junctional segment kyphosis, and preoperative ossification of the anterior longitudinal ligament (OALL). Mean final adjacent-segment range of motion (ROM) was less in those with cranial ALOD (6.9° ± 2.8°) than in those without cranial ALOD (12° ± 4.2°) (p < 0.01). Mean final adjacent-segment ROM was also less in those with caudal ALOD (5.5° ± 2.4º) than in those without caudal ALOD (8.2º ± 3.7º) (p < 0.01). The incidence of CASP-required surgery was higher in those with caudal ALOD (p = 0.02) but no different in those with cranial ALOD (p = 0.69) compared with those without ALOD. Conclusion Factors associated with ALOD were a kyphotic segment adjacent to ACDF, hyperlordotic fusion, preoperative OALL, and short PDD. ALOD was associated with less segmental ROM and, for those with caudal but not cranial ALOD, higher incidence of revision surgery for CASP.

Endoscopic spine surgery (ESS) is growing in popularity worldwide. An expanding body of literature demonstrates rapid functional recovery with reduced morbidity compared to open techniques. Both full endoscopic spine surgery, or uniportal endoscopy, and unilateral biportal endoscopy (UBE) can be employed in conjunction with various navigation and enabling technologies for assistance with localization of anatomic orientation and assessment of the intraoperative target spinal pathology. This review article describes various navigation technologies in ESS, including 2-dimensional (2D) fluoroscopic imaging, 2D fluoroscopic navigation, 3-dimensional C-arm navigation, augmented reality, and spinal robotics. Employment of enabling navigation and emerging technology with the registration of patient-specific anatomy enables clear delineation of anatomic landmarks and facilitation of a successful procedure. Additionally, avoidance of common pitfalls during use of navigation systems in ESS is discussed in this review.

Purpose: To identify factors associated with adjacent-level ossification development (ALOD) after anterior cervical discectomy and fusion (ACDF) and associated clinical outcomes. Methods: We retrospectively reviewed records of 140 adults who underwent primary ACDF for degenerative disc disease. We compared patients with and without ALOD after ACDF. Radiographic measurements and factors associated with ALOD were assessed preoperatively and at minimum 24-month follow-up. Clinical outcomes were incidence of clinical adjacent-segment pathologies (CASP), revision surgery, and patient-reported outcomes. Results: Factors associated with both cranial and caudal ALOD were short plate-to-disc distance (PDD), adjacent-segment kyphosis, hyperlordotic ACDF causing junctional segment kyphosis, and preoperative ossification of the anterior longitudinal ligament (OALL). Mean final adjacent-segment range of motion (ROM) was less in those with cranial ALOD (6.9° ± 2.8°) than in those without cranial ALOD (12° ± 4.2°) (p < 0.01). Mean final adjacent-segment ROM was also less in those with caudal ALOD (5.5° ± 2.4º) than in those without caudal ALOD (8.2º ± 3.7º) (p < 0.01). The incidence of CASP-required surgery was higher in those with caudal ALOD (p = 0.02) but no different in those with cranial ALOD (p = 0.69) compared with those without ALOD. Conclusion Factors associated with ALOD were a kyphotic segment adjacent to ACDF, hyperlordotic fusion, preoperative OALL, and short PDD. ALOD was associated with less segmental ROM and, for those with caudal but not cranial ALOD, higher incidence of revision surgery for CASP.

Endoscopic spine surgery (ESS) is growing in popularity worldwide. An expanding body of literature demonstrates rapid functional recovery with reduced morbidity compared to open techniques. Both full endoscopic spine surgery, or uniportal endoscopy, and unilateral biportal endoscopy (UBE) can be employed in conjunction with various navigation and enabling technologies for assistance with localization of anatomic orientation and assessment of the intraoperative target spinal pathology. This review article describes various navigation technologies in ESS, including 2-dimensional (2D) fluoroscopic imaging, 2D fluoroscopic navigation, 3-dimensional C-arm navigation, augmented reality, and spinal robotics. Employment of enabling navigation and emerging technology with the registration of patient-specific anatomy enables clear delineation of anatomic landmarks and facilitation of a successful procedure. Additionally, avoidance of common pitfalls during use of navigation systems in ESS is discussed in this review.

Purpose: To identify factors associated with adjacent-level ossification development (ALOD) after anterior cervical discectomy and fusion (ACDF) and associated clinical outcomes. Methods: We retrospectively reviewed records of 140 adults who underwent primary ACDF for degenerative disc disease. We compared patients with and without ALOD after ACDF. Radiographic measurements and factors associated with ALOD were assessed preoperatively and at minimum 24-month follow-up. Clinical outcomes were incidence of clinical adjacent-segment pathologies (CASP), revision surgery, and patient-reported outcomes. Results: Factors associated with both cranial and caudal ALOD were short plate-to-disc distance (PDD), adjacent-segment kyphosis, hyperlordotic ACDF causing junctional segment kyphosis, and preoperative ossification of the anterior longitudinal ligament (OALL). Mean final adjacent-segment range of motion (ROM) was less in those with cranial ALOD (6.9° ± 2.8°) than in those without cranial ALOD (12° ± 4.2°) (p < 0.01). Mean final adjacent-segment ROM was also less in those with caudal ALOD (5.5° ± 2.4º) than in those without caudal ALOD (8.2º ± 3.7º) (p < 0.01). The incidence of CASP-required surgery was higher in those with caudal ALOD (p = 0.02) but no different in those with cranial ALOD (p = 0.69) compared with those without ALOD. Conclusion Factors associated with ALOD were a kyphotic segment adjacent to ACDF, hyperlordotic fusion, preoperative OALL, and short PDD. ALOD was associated with less segmental ROM and, for those with caudal but not cranial ALOD, higher incidence of revision surgery for CASP.

Endoscopic spine surgery (ESS) is growing in popularity worldwide. An expanding body of literature demonstrates rapid functional recovery with reduced morbidity compared to open techniques. Both full endoscopic spine surgery, or uniportal endoscopy, and unilateral biportal endoscopy (UBE) can be employed in conjunction with various navigation and enabling technologies for assistance with localization of anatomic orientation and assessment of the intraoperative target spinal pathology. This review article describes various navigation technologies in ESS, including 2-dimensional (2D) fluoroscopic imaging, 2D fluoroscopic navigation, 3-dimensional C-arm navigation, augmented reality, and spinal robotics. Employment of enabling navigation and emerging technology with the registration of patient-specific anatomy enables clear delineation of anatomic landmarks and facilitation of a successful procedure. Additionally, avoidance of common pitfalls during use of navigation systems in ESS is discussed in this review.

Purpose: To identify factors associated with adjacent-level ossification development (ALOD) after anterior cervical discectomy and fusion (ACDF) and associated clinical outcomes. Methods: We retrospectively reviewed records of 140 adults who underwent primary ACDF for degenerative disc disease. We compared patients with and without ALOD after ACDF. Radiographic measurements and factors associated with ALOD were assessed preoperatively and at minimum 24-month follow-up. Clinical outcomes were incidence of clinical adjacent-segment pathologies (CASP), revision surgery, and patient-reported outcomes. Results: Factors associated with both cranial and caudal ALOD were short plate-to-disc distance (PDD), adjacent-segment kyphosis, hyperlordotic ACDF causing junctional segment kyphosis, and preoperative ossification of the anterior longitudinal ligament (OALL). Mean final adjacent-segment range of motion (ROM) was less in those with cranial ALOD (6.9° ± 2.8°) than in those without cranial ALOD (12° ± 4.2°) (p < 0.01). Mean final adjacent-segment ROM was also less in those with caudal ALOD (5.5° ± 2.4º) than in those without caudal ALOD (8.2º ± 3.7º) (p < 0.01). The incidence of CASP-required surgery was higher in those with caudal ALOD (p = 0.02) but no different in those with cranial ALOD (p = 0.69) compared with those without ALOD. Conclusion Factors associated with ALOD were a kyphotic segment adjacent to ACDF, hyperlordotic fusion, preoperative OALL, and short PDD. ALOD was associated with less segmental ROM and, for those with caudal but not cranial ALOD, higher incidence of revision surgery for CASP.

Endoscopic spine surgery (ESS) is growing in popularity worldwide. An expanding body of literature demonstrates rapid functional recovery with reduced morbidity compared to open techniques. Both full endoscopic spine surgery, or uniportal endoscopy, and unilateral biportal endoscopy (UBE) can be employed in conjunction with various navigation and enabling technologies for assistance with localization of anatomic orientation and assessment of the intraoperative target spinal pathology. This review article describes various navigation technologies in ESS, including 2-dimensional (2D) fluoroscopic imaging, 2D fluoroscopic navigation, 3-dimensional C-arm navigation, augmented reality, and spinal robotics. Employment of enabling navigation and emerging technology with the registration of patient-specific anatomy enables clear delineation of anatomic landmarks and facilitation of a successful procedure. Additionally, avoidance of common pitfalls during use of navigation systems in ESS is discussed in this review.