Keun Su Kim1, Dong Hwa Heo. 1. *Department of Neurosurgery, Spine and Spinal Cord Institute, Gangnam Severance Spine Hospital, Yonsei University College of Medicine, Seoul†Department of Neurosurgery, Spine Center, The Leon Wiltse Memorial Hospital, Gyeonggi-do, Korea.
Abstract
STUDY DESIGN: Prospective clinical study. OBJECTIVE: To evaluate the factors that would predispose a patient to heterotopic ossification (HO) formation after cervical arthroplasty. SUMMARY OF BACKGROUND DATA: HO after arthroplasty is one of the complications of cervical total disk replacement (TDR). However, the predisposing factors and pathophysiology of HO have not been precisely described. MATERIALS AND METHODS: We prospectively enrolled and followed up 23 patients, who received single-level arthroplasty with ProDisc-C, for 5 years after the operation. The patients who developed grade 3 or 4 HO were classified into the "high-grade HO group," whereas the patients with grade 0, 1, or 2 HO were classified into the "low-grade HO group." We compared the postoperative changes in the range of motion (ROM) and height of the functional segmental unit (FSU) of the implantation segments between the 2 groups. RESULTS: The mean differences in height and ROM of the FSU were 2.59±1.42 mm and 6.7±3.2 degrees in the high-grade HO group, and 0.87±0.72 mm and 3.1±2.8 degrees in the low-grade HO group. The mean differences in height and ROM of the FSU were significantly higher in the high-grade HO group than in the low-grade HO group (P<0.05). After cervical arthroplasty, the height of the FSU and ROM of the implantation segments were significantly increased in the high-grade HO group compared with the low-grade HO group. CONCLUSIONS: Overcorrection of the height of the FSU and increase in the ROM of the implantation segment may influence the formation of HOs after cervical arthroplasty.
STUDY DESIGN: Prospective clinical study. OBJECTIVE: To evaluate the factors that would predispose a patient to heterotopic ossification (HO) formation after cervical arthroplasty. SUMMARY OF BACKGROUND DATA: HO after arthroplasty is one of the complications of cervical total disk replacement (TDR). However, the predisposing factors and pathophysiology of HO have not been precisely described. MATERIALS AND METHODS: We prospectively enrolled and followed up 23 patients, who received single-level arthroplasty with ProDisc-C, for 5 years after the operation. The patients who developed grade 3 or 4 HO were classified into the "high-grade HO group," whereas the patients with grade 0, 1, or 2 HO were classified into the "low-grade HO group." We compared the postoperative changes in the range of motion (ROM) and height of the functional segmental unit (FSU) of the implantation segments between the 2 groups. RESULTS: The mean differences in height and ROM of the FSU were 2.59±1.42 mm and 6.7±3.2 degrees in the high-grade HO group, and 0.87±0.72 mm and 3.1±2.8 degrees in the low-grade HO group. The mean differences in height and ROM of the FSU were significantly higher in the high-grade HO group than in the low-grade HO group (P<0.05). After cervical arthroplasty, the height of the FSU and ROM of the implantation segments were significantly increased in the high-grade HO group compared with the low-grade HO group. CONCLUSIONS: Overcorrection of the height of the FSU and increase in the ROM of the implantation segment may influence the formation of HOs after cervical arthroplasty.
Authors: Jarle Sundseth; Eva Astrid Jacobsen; Frode Kolstad; Ruth O Sletteberg; Oystein P Nygaard; Lars Gunnar Johnsen; Are Hugo Pripp; Hege Andresen; Oddrun Anita Fredriksli; Erling Myrseth; John A Zwart Journal: Eur Spine J Date: 2016-04-09 Impact factor: 3.134
Authors: Jordan C Xu; Chandni Goel; Michael F Shriver; Joseph E Tanenbaum; Michael P Steinmetz; Edward C Benzel; Thomas E Mroz Journal: Global Spine J Date: 2017-08-15