Anterior percutaneous full-endoscopic transcorporeal decompression for cervical disc herniation: a finite element analysis and long-term follow-up study.

OBJECTIVE: The purpose of this study was to investigate the long-term consequences on the cervical spine after Anterior transcorporeal percutaneous endoscopy cervical discectomy (ATc-PECD) from the biomechanical standpoint. METHODS: A three-dimensional model of the normal cervical spine C2-T1 was established using finite element method. Subsequently, a disc degeneration model and degeneration with surgery model were constructed on the basis of the normal model. The same loading conditions were applied to simulate flexion, extension, lateral bending and axial rotation of the cervical spine. We calculated the cervical range of motion (ROM), intradiscal pressure, and intravertebral body pressure under different motions for observing changes in cervical spine biomechanics after surgery. At the same time, we combined the results of a long-term follow-up of the ATc-PECD, and used imaging methods to measure vertebral and disc height and cervical mobility, the Japanese Orthopaedic Association (JOA) score and visual analog scale (VAS) score were used to assess pain relief and neurological functional recovery. RESULTS: The long-term follow-up results revealed that preoperative JOA score, neck VAS score, hand VAS score, IDH, VBH, and ROM for patients were 9.49 ± 2.16, 6.34 ± 1.68, 5.14 ± 1.48, 5.95 ± 0.22 mm, 15.41 ± 1.68 mm, and 52.46 ± 9.36° respectively. It changed to 15.71 ± 1.13 (P < 0.05), 1.02 ± 0.82 (P < 0.05), 0.77 ± 0.76 (P < 0.05), 4.73 ± 0.26 mm (P < 0.05), 13.67 ± 1.48 mm (P < 0.05), and 59.26 ± 6.72° (P < 0.05), respectively, at 6 years postoperatively. Finite element analysis showed that after establishing the cervical spondylosis model, the overall motion range for flexion, extension, lateral bending, and rotation decreased by 3.298°, 0.753°, 3.852°, and 1.131° respectively. Conversely, after establishing the bone tunnel model, the motion range for these actions increased by 0.843°, 0.65°, 0.278°, and 0.488° respectively, consistent with the follow-up results. Moreover, analysis of segmental motion changes revealed that the increased cervical spine mobility was primarily contributed by the surgical model segments. Additionally, the finite element model demonstrated that bone tunneling could lead to increased stress within the vertebral bodies and intervertebral discs of the surgical segments. CONCLUSIONS: Long-term follow-up studies have shown that ATc-PECD has good clinical efficacy and that ATc-PECD can be used as a complementary method for CDH treatment. The FEM demonstrated that ATc-PECD can lead to increased internal stresses in the vertebral body and intervertebral discs of the operated segments, which is directly related to cervical spine degeneration after ATc-PECD.

Anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord via one vertebra with two bony channels for adjacent two-segment cervical spondylotic myelopathy: a technical note.

BACKGROUND: The current treatments for adjacent two-segment cervical spondylotic myelopathy (CSM) include two-segment anterior cervical discectomy and fusion (ACDF) and single-segment anterior cervical corpectomy and fusion (ACCF). Long-term follow-up has demonstrated that both procedures have complications such as reduced cervical mobility, accelerated degeneration of adjacent segments and loosening of internal fixation screws. The purpose of this study is to demonstrate the feasibility, safety, and efficacy of anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord (APFETDSC) via one vertebra with two bony channels for the treatment of adjacent two-segment CSM and to present our surgical experience. METHODS: Anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord (APFETDSC) via one vertebra with two bony channels was performed for 12 patients with adjacent two-segment CSM with follow-up care for at least 12 months. The Visual analog scale (VAS) and the Japanese Orthopedic Association Score (JOA) were recorded, and modified Macnab criteria were used to evaluate the treatment excellence rate. Radiological examinations, including X-ray, computed tomography (CT) and magnetic resonance imaging (MRI), were used to evaluate spinal cord decompression, intervertebral stability and healing of the bony channel. RESULTS: All 12 patients completed the operation successfully. No postoperative complications, such as dysphagia, Horner's syndrome, or laryngeal recurrent nerve palsy, were found. The postoperative VAS and JOA scores were significantly improved compared with those before surgery(P < 0.001). According to the modified Macnab criteria, the clinical outcome was excellent in 8 cases, good in 3 cases and fine in 1 case at the final follow-up and the excellent and good rate was 91.7%. Postoperative and follow-up imaging showed significant spinal cord decompression, well-healed bony channels and no cervical instability. CONCLUSIONS: This study is the first report of anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord via one vertebra with two bony channels. This procedure has the advantages of less trauma, faster recovery, fewer complications and no need to implant internal fixators. This is a minimally invasive, feasible and safe surgical procedure for patients with adjacent two-segment CSM.

Anterior Percutaneous Full-Endoscopic Transcorporeal with Single-Incision Treatment for Noncontiguous 2-Level Cervical Disc Herniation: Technical Report and Early Follow-Up.

BACKGROUND: Noncontiguous 2-level cervical disc herniation (NCT-CDH) is a common condition that often requires surgical intervention. In this study, we developed a surgical approach for the treatment of NCT-CDH using anterior percutaneous full-endoscopic single incision through the vertebral body. We provide a brief overview of its safety, efficacy, and feasibility, along with a description of our relevant surgical experience. METHODS: A retrospective study was conducted, involving 30 patients who were followed up for at least 12 months. Preoperative and postoperative visual analog scale, Japanese Orthopedic Association scores, Nurick scores, intervertebral disc height, and modified Macnab criteria were recorded. Patients underwent regular radiological evaluations throughout the follow-up period. RESULTS: Postoperative computed tomography, magnetic resonance imaging, and X-ray examinations revealed bone tunnel healing, intact drilled vertebral bodies without collapse, adequate decompression of the spinal canal, and normal cervical mobility. There was a significant improvement in postoperative visual analog scale, Japanese Orthopedic Association scores, Nurick scores, and modified Macnab criteria compared to the preoperative values (P < 0.05). CONCLUSIONS: Our study revealed that the anterior percutaneous full-endoscopic transcorporeal with single-incision treatment for NCT-CDH is a safe and feasible surgical method. Therefore, it can be considered as a viable treatment option for patients with NCT-CDH.

Anterior transcorporeal approach combined with posterior translaminar approach in percutaneous endoscopic cervical discectomy for two-segment cervical disc herniation treatment: a technical report and early follow-up.

OBJECTIVE: Full endoscopic techniques are being gradually introduced from single-segment cervical disc herniation surgery to two-segment cervical disc herniation surgery. However, there is no suitable full endoscopic treatment for mixed-type two-segment cervical disc herniation (MTCDH) in which one segment herniates in front of the spinal cord and the other segment herniates behind the spinal cord. Therefore, we introduce a new full endoscopic technique by combining an anterior transcorporeal approach and a posterior translaminar approach. In addition, we provide a brief description of its safety, efficacy, feasibility, and surgical points. METHODS: Thirty patients with MTCDH were given full endoscopic surgical treatment by a combined transcorporeal and transforaminal approach and were followed up for at least 12 months. RESULTS: Clinical assessment scales showed that the patient's symptoms and pain were significantly reduced postoperatively. Imaging results showed bony repair of the surgically induced bone defect and the cervical Cobb angle was increased. No serious complications occurred. CONCLUSION: This technique enables minimally invasive surgery to relieve the compression of the spinal cord by MTCDH. It avoids the fusion of the vertebral body for internal fixation, preserves the vertebral motion segments, avoids medical destruction of the cervical disc to the greatest extent possible, and expands the scope of adaptation of full endoscopic technology in cervical surgery.