Microsurgical resection of ossification of the posterior longitudinal ligament in the thoracic spine via the transthoracic approach without spinal fusion: case series and technical note

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>Surgical management of thoracic ossification of the posterior longitudinal ligament (OPLL) remains challenging because of the anatomical complexity of the thoracic spine and the fragility of the thoracic spinal cord. Several surgical approaches have been described, but it remains unclear which of these is the most effective. The present study describes the microsurgical removal of OPLL in the middle thoracic level via the transthoracic anterolateral approach without spinal fusion, including the surgical outcome and operative tips.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>Between 2002 and 2017, a total of 8 patients with thoracic myelopathy due to OPLL were surgically treated via the transthoracic anterolateral approach without spinal fusion. The surgical techniques are described in detail. Clinical outcome, surgical complications, and the pre- and postoperative thoracic kyphotic angle were assessed.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>The mean patient age at the time of surgery was 55 years (range 47–77 years). There were 5 women and 3 men. The surgically treated levels were within T3–9. The clinical symptoms and Japanese Orthopaedic Association (JOA) score improved postoperatively in 7 cases, but did not change in 1 case. The mean JOA score increased from 6.4 preoperatively to 7.5 postoperatively (recovery rate 26%). Intraoperative CSF leakage occurred in 4 cases, and was successfully treated with fibrin glue sealing and spinal drainage. The mean follow-up period was 82.6 months (range 15.3–169 months). None of the patients had deterioration of the thoracic kyphotic angle.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>Anterior decompression is the logical and ideal procedure to treat thoracic myelopathy caused by OPLL on the concave side of the spinal cord; however, this procedure is technically demanding. Microsurgery via the transthoracic anterolateral approach enables direct visualization of the thoracic ventral ossified lesion. The use of microscopic procedures might negate the need for bone grafting or spinal instrumentation.</jats:p></jats:sec>

The Transaxillary Approach as a Direct Route in the Management of Upper Thoracic Spine Pathology: A Technical Note with Case Series

“…However, if the cerebrospinal fluid (CSF) leak is associated with persistent postural headache, poor wound healing, and appreciable collection of CSF in the subcutaneous region of the back, a subarachnoid drain may be necessary to control symptoms. In the study conducted by Kanematsu et al [ 25 ], eight patients were treated by anterior transthoracic techniques, and the OPLL existed from the T3 to T9 vertebral levels. The mean blood loss was 346 mL, and the mean operative duration was 450 minutes.…”

“…Four cases of intraoperative CSF leakage were encountered. The mean JOA score improved significantly during the follow-up period [ 25 ].…”

Anterior shift of the ventral dura mater: A novel concept of the posterior surgery for ossification of the posterior longitudinal ligament in thoracic spine

“…Thereafter, many spine surgeons have challenged this intractable disease with many kinds of procedures, including laminectomy with or without resection of the dentate ligaments ( 1 , 20 ), anterior decompression and fusion through a thoracotomy ( 21 , 22 ), posterior decompression with instrumented spinal fusion ( 4 , 23 ), and anterior decompression through a posterior approach, the so-called Ohtsuka procedure ( 24 ). More specific procedures include circumspinal decompression through a posterior approach with thoracotomy ( 25 ), through a single posterior approach ( 9 ) and a posterolateral approach ( 26 ), staged spinal decompression through a posterior approach ( 27 ), and single-stage mini-thoracotomy without spinal fusion ( 3 , 28 ).…”

“…The rate of postoperative neurological deterioration is higher ( 4 – 7 , 9 ). In addition, anterior decompression through thoracotomy has a significant risk of pulmonary complications, including cerebrospinal fluid leakage into the thoracic cavity ( 3 , 5 ).…”

“…The difficulty of surgery depends on two reasons: anatomical features and perioperative complications. Anatomically, the spinal cord has a particularly vulnerable region, usually between T4 and T9, called the “watershed zone” with poor blood supply ( 2 , 3 ). In addition, the thoracic spine is naturally kyphotic, and decompressive laminectomy is less effective because of the restricted postoperative backward shift of the spinal cord ( 4 ).…”