1.Radiographic and Clinical Outcomes of Transverse Process Hook Placement at the Proximal Thoracic Upper Instrumented Vertebra in Adult Spinal Deformity Surgery
Sang Hun LEE ; Micheal RAAD ; Andrew H. KIM ; David B. COHEN ; Khaled M. KEBAISH
Neurospine 2024;21(2):502-509
Objective:
Few studies have reported radiographic and clinical outcomes of transverse process hook (TPH) placement at the proximal thoracic upper instrumented vertebra (UIV) in adult spinal deformity (ASD) surgery. This study aims to investigate radiographic and clinical outcomes of TPH placement at the UIV for ASD surgery.
Methods:
This is a retrospective cohort of 56 patients with ASD (age, 59 ± 13 years; followup, 44 ± 19 months) from Johns Hopkins Hospital, who underwent long posterior spinal fusion to the proximal thoracic spine (T2–5). Visual analogue scale (VAS) for back pain, Oswestry Disability Index (ODI), 36-item Short Form health survey scores, thoracic kyphosis (TK), lumbar lordosis, sacral slope, pelvic tilt, pelvic incidence, proximal junctional kyphosis (PJK) angle, PJK incidence, pattern of PJK, grades of TPH dislodgement, revision surgery, and factors associated with high-grade TPH dislodgement were analyzed.
Results:
VAS for back pain and ODI values improved significantly from preoperatively to final follow-up. Mean change in PJK angle was 12° (range, 0.5°–43°). Twenty patients (36%) developed PJK, of whom 13 had compression fractures at 1 vertebra distal to the UIV (UIV–1). Final TPH position was stable in 42 patients (75%). In most patients (86%), TPH dislodgement did not progress after 6-month postoperative follow-up. Three patients (5.3%) underwent revision surgery to extend the fusion because of symptomatic PJK. Unstable TPH position was associated only with revision surgery and TK.
Conclusion
TPH placement at the proximal thoracic UIV for long fusion showed favorable clinical and radiographic outcomes in terms of the incidence of PJK and mean PJK angle at mean 44-month follow-up. TPHs placed in the proximal thoracic UIV were in stable position in 75% of patients. Compression fracture at UIV–1 was the most common pattern of PJK. PJK angle progression was greater in revision cases and in patients with greater preoperative thoracic kyphosis.
2.Risk Factors for “Adjacent-Level Ossification Development” Other Than Short Plate-to-Disc Distance and Clinical Implications for Adjacent-Segment Pathology
Sang Hun LEE ; Micheal RAAD ; David B. COHEN ; Khaled M. KEBAISH ; Lee H. RILEY III
Neurospine 2025;22(1):194-201
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.
3.Radiographic and Clinical Outcomes of Transverse Process Hook Placement at the Proximal Thoracic Upper Instrumented Vertebra in Adult Spinal Deformity Surgery
Sang Hun LEE ; Micheal RAAD ; Andrew H. KIM ; David B. COHEN ; Khaled M. KEBAISH
Neurospine 2024;21(2):502-509
Objective:
Few studies have reported radiographic and clinical outcomes of transverse process hook (TPH) placement at the proximal thoracic upper instrumented vertebra (UIV) in adult spinal deformity (ASD) surgery. This study aims to investigate radiographic and clinical outcomes of TPH placement at the UIV for ASD surgery.
Methods:
This is a retrospective cohort of 56 patients with ASD (age, 59 ± 13 years; followup, 44 ± 19 months) from Johns Hopkins Hospital, who underwent long posterior spinal fusion to the proximal thoracic spine (T2–5). Visual analogue scale (VAS) for back pain, Oswestry Disability Index (ODI), 36-item Short Form health survey scores, thoracic kyphosis (TK), lumbar lordosis, sacral slope, pelvic tilt, pelvic incidence, proximal junctional kyphosis (PJK) angle, PJK incidence, pattern of PJK, grades of TPH dislodgement, revision surgery, and factors associated with high-grade TPH dislodgement were analyzed.
Results:
VAS for back pain and ODI values improved significantly from preoperatively to final follow-up. Mean change in PJK angle was 12° (range, 0.5°–43°). Twenty patients (36%) developed PJK, of whom 13 had compression fractures at 1 vertebra distal to the UIV (UIV–1). Final TPH position was stable in 42 patients (75%). In most patients (86%), TPH dislodgement did not progress after 6-month postoperative follow-up. Three patients (5.3%) underwent revision surgery to extend the fusion because of symptomatic PJK. Unstable TPH position was associated only with revision surgery and TK.
Conclusion
TPH placement at the proximal thoracic UIV for long fusion showed favorable clinical and radiographic outcomes in terms of the incidence of PJK and mean PJK angle at mean 44-month follow-up. TPHs placed in the proximal thoracic UIV were in stable position in 75% of patients. Compression fracture at UIV–1 was the most common pattern of PJK. PJK angle progression was greater in revision cases and in patients with greater preoperative thoracic kyphosis.
4.Risk Factors for “Adjacent-Level Ossification Development” Other Than Short Plate-to-Disc Distance and Clinical Implications for Adjacent-Segment Pathology
Sang Hun LEE ; Micheal RAAD ; David B. COHEN ; Khaled M. KEBAISH ; Lee H. RILEY III
Neurospine 2025;22(1):194-201
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.
5.Radiographic and Clinical Outcomes of Transverse Process Hook Placement at the Proximal Thoracic Upper Instrumented Vertebra in Adult Spinal Deformity Surgery
Sang Hun LEE ; Micheal RAAD ; Andrew H. KIM ; David B. COHEN ; Khaled M. KEBAISH
Neurospine 2024;21(2):502-509
Objective:
Few studies have reported radiographic and clinical outcomes of transverse process hook (TPH) placement at the proximal thoracic upper instrumented vertebra (UIV) in adult spinal deformity (ASD) surgery. This study aims to investigate radiographic and clinical outcomes of TPH placement at the UIV for ASD surgery.
Methods:
This is a retrospective cohort of 56 patients with ASD (age, 59 ± 13 years; followup, 44 ± 19 months) from Johns Hopkins Hospital, who underwent long posterior spinal fusion to the proximal thoracic spine (T2–5). Visual analogue scale (VAS) for back pain, Oswestry Disability Index (ODI), 36-item Short Form health survey scores, thoracic kyphosis (TK), lumbar lordosis, sacral slope, pelvic tilt, pelvic incidence, proximal junctional kyphosis (PJK) angle, PJK incidence, pattern of PJK, grades of TPH dislodgement, revision surgery, and factors associated with high-grade TPH dislodgement were analyzed.
Results:
VAS for back pain and ODI values improved significantly from preoperatively to final follow-up. Mean change in PJK angle was 12° (range, 0.5°–43°). Twenty patients (36%) developed PJK, of whom 13 had compression fractures at 1 vertebra distal to the UIV (UIV–1). Final TPH position was stable in 42 patients (75%). In most patients (86%), TPH dislodgement did not progress after 6-month postoperative follow-up. Three patients (5.3%) underwent revision surgery to extend the fusion because of symptomatic PJK. Unstable TPH position was associated only with revision surgery and TK.
Conclusion
TPH placement at the proximal thoracic UIV for long fusion showed favorable clinical and radiographic outcomes in terms of the incidence of PJK and mean PJK angle at mean 44-month follow-up. TPHs placed in the proximal thoracic UIV were in stable position in 75% of patients. Compression fracture at UIV–1 was the most common pattern of PJK. PJK angle progression was greater in revision cases and in patients with greater preoperative thoracic kyphosis.
6.Risk Factors for “Adjacent-Level Ossification Development” Other Than Short Plate-to-Disc Distance and Clinical Implications for Adjacent-Segment Pathology
Sang Hun LEE ; Micheal RAAD ; David B. COHEN ; Khaled M. KEBAISH ; Lee H. RILEY III
Neurospine 2025;22(1):194-201
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.
7.Radiographic and Clinical Outcomes of Transverse Process Hook Placement at the Proximal Thoracic Upper Instrumented Vertebra in Adult Spinal Deformity Surgery
Sang Hun LEE ; Micheal RAAD ; Andrew H. KIM ; David B. COHEN ; Khaled M. KEBAISH
Neurospine 2024;21(2):502-509
Objective:
Few studies have reported radiographic and clinical outcomes of transverse process hook (TPH) placement at the proximal thoracic upper instrumented vertebra (UIV) in adult spinal deformity (ASD) surgery. This study aims to investigate radiographic and clinical outcomes of TPH placement at the UIV for ASD surgery.
Methods:
This is a retrospective cohort of 56 patients with ASD (age, 59 ± 13 years; followup, 44 ± 19 months) from Johns Hopkins Hospital, who underwent long posterior spinal fusion to the proximal thoracic spine (T2–5). Visual analogue scale (VAS) for back pain, Oswestry Disability Index (ODI), 36-item Short Form health survey scores, thoracic kyphosis (TK), lumbar lordosis, sacral slope, pelvic tilt, pelvic incidence, proximal junctional kyphosis (PJK) angle, PJK incidence, pattern of PJK, grades of TPH dislodgement, revision surgery, and factors associated with high-grade TPH dislodgement were analyzed.
Results:
VAS for back pain and ODI values improved significantly from preoperatively to final follow-up. Mean change in PJK angle was 12° (range, 0.5°–43°). Twenty patients (36%) developed PJK, of whom 13 had compression fractures at 1 vertebra distal to the UIV (UIV–1). Final TPH position was stable in 42 patients (75%). In most patients (86%), TPH dislodgement did not progress after 6-month postoperative follow-up. Three patients (5.3%) underwent revision surgery to extend the fusion because of symptomatic PJK. Unstable TPH position was associated only with revision surgery and TK.
Conclusion
TPH placement at the proximal thoracic UIV for long fusion showed favorable clinical and radiographic outcomes in terms of the incidence of PJK and mean PJK angle at mean 44-month follow-up. TPHs placed in the proximal thoracic UIV were in stable position in 75% of patients. Compression fracture at UIV–1 was the most common pattern of PJK. PJK angle progression was greater in revision cases and in patients with greater preoperative thoracic kyphosis.
8.Risk Factors for “Adjacent-Level Ossification Development” Other Than Short Plate-to-Disc Distance and Clinical Implications for Adjacent-Segment Pathology
Sang Hun LEE ; Micheal RAAD ; David B. COHEN ; Khaled M. KEBAISH ; Lee H. RILEY III
Neurospine 2025;22(1):194-201
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.
9.Radiographic and Clinical Outcomes of Transverse Process Hook Placement at the Proximal Thoracic Upper Instrumented Vertebra in Adult Spinal Deformity Surgery
Sang Hun LEE ; Micheal RAAD ; Andrew H. KIM ; David B. COHEN ; Khaled M. KEBAISH
Neurospine 2024;21(2):502-509
Objective:
Few studies have reported radiographic and clinical outcomes of transverse process hook (TPH) placement at the proximal thoracic upper instrumented vertebra (UIV) in adult spinal deformity (ASD) surgery. This study aims to investigate radiographic and clinical outcomes of TPH placement at the UIV for ASD surgery.
Methods:
This is a retrospective cohort of 56 patients with ASD (age, 59 ± 13 years; followup, 44 ± 19 months) from Johns Hopkins Hospital, who underwent long posterior spinal fusion to the proximal thoracic spine (T2–5). Visual analogue scale (VAS) for back pain, Oswestry Disability Index (ODI), 36-item Short Form health survey scores, thoracic kyphosis (TK), lumbar lordosis, sacral slope, pelvic tilt, pelvic incidence, proximal junctional kyphosis (PJK) angle, PJK incidence, pattern of PJK, grades of TPH dislodgement, revision surgery, and factors associated with high-grade TPH dislodgement were analyzed.
Results:
VAS for back pain and ODI values improved significantly from preoperatively to final follow-up. Mean change in PJK angle was 12° (range, 0.5°–43°). Twenty patients (36%) developed PJK, of whom 13 had compression fractures at 1 vertebra distal to the UIV (UIV–1). Final TPH position was stable in 42 patients (75%). In most patients (86%), TPH dislodgement did not progress after 6-month postoperative follow-up. Three patients (5.3%) underwent revision surgery to extend the fusion because of symptomatic PJK. Unstable TPH position was associated only with revision surgery and TK.
Conclusion
TPH placement at the proximal thoracic UIV for long fusion showed favorable clinical and radiographic outcomes in terms of the incidence of PJK and mean PJK angle at mean 44-month follow-up. TPHs placed in the proximal thoracic UIV were in stable position in 75% of patients. Compression fracture at UIV–1 was the most common pattern of PJK. PJK angle progression was greater in revision cases and in patients with greater preoperative thoracic kyphosis.
10.Risk Factors for “Adjacent-Level Ossification Development” Other Than Short Plate-to-Disc Distance and Clinical Implications for Adjacent-Segment Pathology
Sang Hun LEE ; Micheal RAAD ; David B. COHEN ; Khaled M. KEBAISH ; Lee H. RILEY III
Neurospine 2025;22(1):194-201
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.