Effects of a new anatomical adaptive titanium mesh cage on supportive load at the cervical endplate: a morphological and biomechanical study / 南方医科大学学报

OBJECTIVE@#To assess the geometrical matching of a new anatomical adaptive titanium mesh cage (AA-TMC) with the endplate and its effect on cervical segmental alignment reconstruction in single- and two-level anterior cervical corpectomy and fusion (ACCF) and compare the compressive load at the endplate between the AA-TMC and the conventional titanium mesh cage (TMC).@*METHODS@#Twelve cervical cadaveric specimens were used to perform single- and two-level ACCF. The interbody angle (IBA), interbody height (IBH) and the interval between the AA-TMC and the endplate were evaluated by comparison of the pre- and postoperative X-ray images. The maximum load at the endplate was compared between the AA-TMC and TMC based on American Society for Testing and Materials (ASTM) F2267 standard.@*RESULTS@#No significant differences were found between the preoperative and postoperative IBA and IBH in either single-level ACCF (11.62°±2.67° 12.13°±0.69° and 23.90±2.18 mm 24.23±1.13 mm, respectively; > 0.05) or two-level ACCF (15.63°±5.06° 16.16°±1.05°and 42.93±3.51 mm 43.04±1.70 mm, respectively; > 0.05). The mean interval between the AA-TMC and the endplate was 0.37 ± 0.3 mm. Compared to the conventional TMC, the use of AA-TMC significantly increased the maximum load at the endplate in both single-level ACCF (719.7±5.5 N 875.8±5.2 N, < 0.05) and two-level ACCF (634.3±5.9 N 873±6.1 N, < 0.05).@*CONCLUSIONS@#The use of AA-TMC in single-level and two-level ACCF can significantly increase the maximum load at the endplate to lower the possibility of implant subsidence and allows effective reconstruction of the cervical alignment.

Anterior Cervical Fusion and Plate Stabilization in Patients with Lower Cervical Lesions

Anterior cervical discectomy and fusion is an efficacious procedure used to treat a variety of cervical spinal disorders, including spondylosis, myelopathy, herniated discs, trauma, and degenerative disc diseases. Refinements in instrumentation for the cervical spine have led to an increase in experience with these devices during the past decade. The need for postoperative immobilization, required to stabilize the patient while the fusion mass heals, is decreased or negated by internal fixation. The authors analyzed the results in 30 patients(22 traumatic; 8 non-traumatic) with lower cervical lesions, who underwent anterior interbody fixation with cervical plates between April, 1994 and June, 1996. We used either a unicortical(Orion TM) or bicortical screw system(Top TM): these two types of plates had no specific differences, but the Orion TM was easier and safer to operate. Although postoperative stability was successfully attained in all patients, two screw-related complications, which were fully resolved without causing any specific problems, were detected during the postoperative follow-up period. In nontraumatic lesions, we measured pre-and postoperative interbody heights at ten levels; postoperative interbody height was well preserved for one year. In conclusion, internal fixation may provide added security to the nervous system before bony fusion occurs, may lessen the number of levels requiring fusion, may increase the probability of successful fusion, and is conducive to early patient mobilization.