Nanohydroxyapatite/polyamide 66 strut subsidence after one-level corpectomy: underlying mechanism and effect on cervical neurological function

Abstract

The aim of this study was to investigate n-HA/PA66 strut subsidence after one-level in Anterior cervical corpectomy decompression and fusion (ACCF) and its effect on treatment outcomes to better understand the underlying mechanism and related risk factors. In total, 56 patients undergoing ACCF using n-HA/PA66 struts were analysed retrospectively. After a 12-month follow-up, the height of the fused segments and fused intervertebral heights were measured, the neurological findings were evaluated using the Japanese Orthopedic Association (JOA) and axial pain was assessed using a Visual Analogue Scale(VAS). Subsidence was defined as a decrease in the height of the fused segments or the fused intervertebral body greater than 3 mm compared with that on postoperative day one, and all patients were assigned to the n-HA/PA66 strut subsidence and control groups. In total, 45 patients experienced n-HA/PA66 strut subsidence during the postoperative (3 ± 2.42/3.11 ± 2.01) months. No significant differences were observed in sex, age, hospitalization time, surgical haemorrhage,bone mineral density (BMD), or height in the n-HA/PA66 strut group. The JOA and VAS of neck pain in the control group improved more than those in the subsidence group, suggesting that subsidence might be correlated with poor improvement of neurological function. In conclusion, n-HA/PA66 strut subsidence is a common complication after ACCF, and the reduced height of the postoperative fused segments and the height reduction in the postoperative fused intervertebral bodies are independent risk factors of n-HA/PA66 strut subsidence.

Comparative Analysis of 3D-Printed Artificial Vertebral Body Versus Titanium Mesh Cage in Repairing Bone Defects Following Single-Level Anterior Cervical Corpectomy and Fusion

“…ACCF has the advantages of complete decompression and ample exposure [ 1 , 2 ]. Since first reported in the 1950s, it has been widely used in the treatment of various cervical spine diseases and has become one of the main surgical procedures used for the treatment of CSM [ 3 , 4 ]. There are many methods for the reconstruction of local cervical spine stability after decompression.…”

“…Anterior cervical compression and fusion (ACCF) has the advantages of complete decompression and ample exposure, so it is extensively used in the treatment of a variety of cervical-related diseases [ 1 , 2 ], such as cervical spondylotic myelopathy (CSM), cervical fracture, tumor, and tuberculosis. ACCF has become one of the main surgical methods for treating CSM [ 3 , 4 ]. Titanium mesh cage (TMC) is currently the most common implant for repairing bone defects during ACCF, but TMC subsidence may occur after surgery and cause a series of changes and clinical symptoms [ 4 – 6 ].…”

“…ACCF has become one of the main surgical methods for treating CSM [ 3 , 4 ]. Titanium mesh cage (TMC) is currently the most common implant for repairing bone defects during ACCF, but TMC subsidence may occur after surgery and cause a series of changes and clinical symptoms [ 4 – 6 ]. The excessive subsidence of TMC causes changes in intervertebral height and cervical curvature, resulting in compression of nerve roots, ligamenta flava fold, and cervical kyphosis.…”

Imaging evaluation of nano-hydroxyapatite/polyamide 66 strut in cervical construction after 1-level corpectomy: a retrospective study of 520 patients

“…Slight pseudarthrosis could easily be observed. Precise fusion of the n-HA/PA66 strut based on 3-D CT and on radiography was accurately followed [14][15][16][17][18][19].…”

“…It means that a possible progression from type a to type c indicates an insufficient bony fusion. Once a type c pattern is observed, strict bracing of the cervical spine or even revision surgery will need to be considered [16][17][18][19]. However, no signs of plate or screw loosening were observed and no patients received revision surgery.…”