OBJECTIVE: To compare the effectiveness of a zero-profile three-dimensiaonal (3D)-printed microporous titanium alloy Cage and a conventional titanium plate combined with a polyether-ether-ketone (PEEK)-Cage in the treatment of single-segment cervical spondylotic myelopathy (CSM) by anterior cervical discectomy and fusion (ACDF). METHODS: The clinical data of 83 patients with single-segment CSM treated with ACDF between January 2022 and January 2023 were retrospectively analyzed, and they were divided into 3D-ZP group (35 cases, using zero-profile 3D-printed microporous titanium alloy Cage) and CP group (48 cases, using titanium plate in combination with PEEK-Cage). There was no significant difference in gender, age, disease duration, surgical intervertebral space, and preoperative Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS) score, neck disability index (NDI), vertebral height at the fusion segment, Cobb angle, and other baseline data between the two groups (P>0.05). The operation time, intraoperative blood loss, hospital stay, complications, interbody fusion, and prosthesis subsidence were recorded and compared between the two groups. VAS score, NDI, and JOA score were used to evaluate the improvement of pain and function before operation, at 3 months after operation, and at last follow-up, and the vertebral height at the fusion segment and Cobb angle were measured by imaging. The degree of dysphagia was assessed by the Bazaz dysphagia scale at 1 week and at last follow-up. RESULTS: The operation was successfully completed in all the 83 patients. There was no significant difference in intraoperative blood loss and hospital stay between the two groups (P>0.05), but the operation time in the 3D-ZP group was significantly shorter than that in the CP group (P<0.05). Patients in both groups were followed up 24-35 months, with an average of 25.3 months, and there was no significant difference in the follow-up time between the two groups (P>0.05). The incidence and grade of dysphagia in CP group were significantly higher than those in 3D-ZP group at 1 week after operation and at last follow-up (P<0.05). There was no dysphagia in 3D-ZP group at last follow-up. There was no complication such as implant breakage or displacement in both groups. The intervertebral fusion rates of 3D-ZP group and CP group were 65.71% (23/35) and 60.42% (29/48) respectively at 3 months after operation, and there was no significant difference between the two groups [OR (95%CI)=1.256 (0.507, 3.109), P=0.622]. The JOA score, VAS score, and NDI significantly improved in the 3D-ZP group at 3 months and at last follow-up when compared with preoperative ones (P<0.05), but there was no significant difference between the two groups (P>0.05). There was no significant difference in the improvement rate of JOA between the two groups at last follow-up (P>0.05). At 3 months after operation and at last follow-up, the vertebral height at the fusion segment and Cobb angle significantly improved in both groups, and the two indexes in 3D-ZP group were significantly better than those in CP group (P<0.05). At last follow-up, the incidence of prosthesis subsidence in 3D-ZP group (8.57%) was significantly lower than that in CP group (29.16%) (P<0.05). CONCLUSION The application of zero-profile 3D-printed Cage and titanium plate combined with PEEK-Cage in single-segment ACDF can both reconstruct the stability of cervical spine and achieve good effectiveness. Compared with the latter, the application of the former in ACDF can shorten the operation time, reduce the incidence of prosthesis subsidence, and reduce the incidence of dysphagia.
Humans ; Spinal Fusion/instrumentation* ; Titanium ; Cervical Vertebrae/surgery* ; Diskectomy/instrumentation* ; Bone Plates ; Male ; Printing, Three-Dimensional ; Female ; Retrospective Studies ; Middle Aged ; Treatment Outcome ; Benzophenones ; Adult ; Spondylosis/surgery* ; Aged ; Polymers ; Ketones ; Polyethylene Glycols

Clinical features of and genetic mutations in two cases of pseudohypoparathyroidism type Ⅰ a(PHP Ⅰ a) with early-onset skin nodules were analyzed.Both of the two patients were males,and their ages at onset were 2 and 3 months respectively.They both presented with early-onset skin nodules as the main clinical manifestation,and were clinically characterized by a round face,short neck and early obesity.Histopathological examination of skin lesions showed subcutaneous ectopic osteogenesis in both patients.The first patient had low blood calcium,high blood phosphorus,high parathyroid hormone (PTH),and gene sequencing showed a heterozygous mutation c.399delT causing a T base deletion at position 399 in exon 5 of the GNAS gene.The second patient had normal blood calcium and phosphorus levels as well as normal PTH levels at early stage,and gene sequencing showed a heterozygous mutation c.939delT causing a T base deletion at position 939 in exon 9 of the GNAS gene.The blood PTH level was found to increase in the second patient after 1-year follow-up.Both the patients were confirmedly diagnosed with PHP Ⅰa.After treatment with vitamin D3,no new skin nodules occurred,and the blood calcium and phosphorus levels returned to normal.