Perimedullary arteriovenous fistula (AVF) is a relatively rare spinal vascular malformation. Although it has traditionally been considered to be a congenital lesion, some cases identified in adults have suggested that the lesion may be acquired. The etiology and exact mechanism of these lesions are unknown. The authors present a case of a perimedullary AVF caused by a direct stabbing injury of the spinal cord and induced by subsequent kyphosis, and they discuss the pathogenesis and treatment strategy.
Yahui Bai, Xinglong Zhi, Fengzeng Jian, Hongqi Zhang and Feng Ling
Wanru Duan, Dean Chou, Bowen Jiang, Zhenlei Liu, Xinghua Zhao, Zhiyuan Xia, Fengzeng Jian and Zan Chen
The treatment of atlantoaxial dislocation (AAD) and basilar invagination (BI) is challenging, especially in symptomatic patients with a history of previous surgery. Although seldom reported, posterior revision surgery to revise prior constructs can be advantageous over an anterior or combined approach. The authors describe their experience in performing posterior revision surgery using Goel’s technique.
The authors reviewed patients with AAD and BI who had undergone previous posterior surgery at the cranio-cervical junction between January 2016 and September 2017. All of these patients underwent revision surgery from a posterior approach. The Japanese Orthopaedic Association (JOA) score was used to assess clinical symptoms before and after surgery. The distance from the tip of the odontoid to Chamberlain’s line, atlantodental interval (ADI), and clivus-canal angle (CCA) were used for radiographic assessment before and after surgery.
Twelve consecutive patients were reviewed. Prior surgeries were as follows: 4 patients (4/12) with posterior osseous decompression without fusion, 7 (7/12) with reduction and fusion without decompression, and 1 (1/12) with posterior osseous decompression and reduction and fusion. With the use of Goel’s technique for revision in these cases, distraction using facet spacers afforded release of the anterior soft tissue from a posterior approach. The occiput was fixated to C2 using a cantilever technique, and autologous cancellous bone was grafted into the intraarticular joints. In all 12 patients, complete reduction of BI and AAD were achieved without injury to nerves or vessels. All patients had evidence of bony fusion on CT scans within 18 months of follow-up.
Posterior revision surgery using Goel’s technique is an effective and safe revision salvage surgery for symptomatic patients with AAD and BI.
Can Zhang, Chih-Chang Chang, Praveen V. Mummaneni, Chenghua Yuan, Sanjay Dhall, Fengzeng Jian, Nalin Gupta and Dean Chou
Recurrent tethered cord syndrome (TCS), believed to result from tension on the distal portion of the spinal cord, causes a constellation of neurological symptoms. Detethering surgery has been the traditional treatment for TCS. However, in cases of recurrent TCS, there is a risk of new neurological deficits developing, and subsequent retethering is difficult to prevent. Spinal column shortening has been proposed as an alternative technique to reduce the tension on the spinal cord without incurring the morbidity of revision surgery on the spinal cord. The authors compared the perioperative outcomes and morbidity of patients who were treated with one or the other procedure.
The medical records of 16 adult patients with recurrent TCS who were treated between 2005 and 2018 were reviewed. Eight patients underwent spinal column shortening, and 8 patients underwent revision detethering surgery. Patient demographics, clinical outcomes, and perioperative factors were analyzed. The authors include a video to illustrate their technique of spinal column shortening.
Within the spinal column shortening group, no patients experienced any complications, and all 8 patients either improved or stabilized with regard to lower-extremity and bowel and bladder function. Within the revision detethering group, 2 patients had worsening of lower-extremity strength, 3 patients had worsening of bowel and bladder function, and 1 patient had improvement in bladder function. Also, 3 patients had wound-related complications. The median estimated blood loss was 731 ml in the shortening group and 163 ml in the revision detethering group. The median operative time was 358 minutes in the shortening group and 226 minutes in the revision detethering group.
Clinical outcomes were comparable between the groups, but none of the spinal column shortening patients experienced worsening, whereas 3 of the revision detethering patients did and also had wound-related complications. Although the operative times and blood loss were higher in the spinal column shortening group, this procedure may be an alternative to revision detethering in extremely scarred or complex wound revision cases.