Arthrodesis of the Lumbar Vertebrae after Radiosurgery for Residual Malignant Schwannoma

Domenico Murrone, Bruno Romanelli, Aldo Ierardi

In past years, instrumentation options for stabilization were very limited and spinal surgery was restricted to dorsal decompression alone. As technology evolved, surgeons began to approach the spine using lateral or ventral approaches, in addition to the standard dorsal approach using fusion and instrumentation and the effect of radiation on bones has been extensively described. CASE REPORT: 51 year old patient who had undergone in 2013 subtotal resection of malignant schwannoma (Ki67> 50%) at L4 level right through laminectomy and artrectomia partial at L4 and L5 with outcomes of mild erectile dysfunction. It was performed following adjuvant radiotherapy at L4-L5 level (46 Gy). In April 2015 reported lumbar accidental trauma with detection of burst fracture and diastasis intracanal of large fragment at L3 level. Neurologically the patient had no additional neurological deficits than in the past. After stabilization of hemodynamic parameters, the patient underwent arthrodesis L2-L4 bilateral transpedicular percutaneous The postoperative course was normal with patient mobilization with lumbar bust in the third day. DISCUSSION: It is commonly known that radiation hinders the fusion process and reduces the strength of bones. The effect of radiotherapy on bony metabolism has been widely discussed but its role in influencing the failure of instrumented fusion has not yet been definitively analysed. Moreover, the most appropriate technique of instrumented fusion to be used after radiotherapy is not established. CONCLUSIONS: In the literature there are no significant studies about the spinal instrumentation after radiosurgery. From our point of view, the fusion is possible due to the extreme hardness of the vertebrae previously irradiated. The choice of the arthrodesis percutaneously depended on the need to avoid significant complications.