Anterior Decompression and Fusion for Thoracic OPLL: Transthoracic and Transsternal Approaches

Ossification of the poster longitudinal ligament (OPLL) lessens the sagittal diameter of the canal and compresses the spinal cord anteriorly. Anterior decompression directly relieves the spinal cord, as well as restores the spinal cord to its original position. Anterior decompression for OPLL is a rational operative method. In the case of the thoracic spine, the approach method differs depending on the spinal level. The manubrium splitting approach is indicated for cases of OPLL located from cervical to T3. Transpleural approach is indicated below T2 level to thoraco-lumbar level. For 55 cases, we performed anterior decompression for thoracic OPLL, and noted the surgical approach, surgical result. The JOA (Japanese Orthopedic Association) scores were investigated. We modified the scoring system for cervical myelopathy established by the JOA by excluding items involving the upper extremities. Surgical approaches were transpleural approach in 47 cases and manubrium splitting approach in 8 cases. The mean recovery rate was 42.7% for manubrium splitting approach and 53.8% with transpleural approach. The frequency of laryngeal nerve palsy was over 50% with manubrium splitting approach. Leakage of cerebrospinal fluid in the thoracic cavity was seen frequently with the transpleural approach; however, it healed spontaneously without additional treatment. Although the anterior approach is associated with some problems (such as surgical invasiveness and postoperative complications), this surgical method resulted in positive outcomes, indicating that it is a useful technique.