Anterior thoracic foraminotomy through mini-thoracotomy for the treatment of giant thoracic disc herniations

Abstract

A retrospective review of a case series. Giant thoracic disc herniations remain a surgical challenge and historically have been associated with significant complications. While neurological outcomes have improved with the abandonment of decompressive laminectomy, the attempt to minimize surgical complications and associated morbidities continues through less-invasive approaches. With the current study, we describe a surgical technique to treat giant thoracic disc herniations while minimizing approach-related morbidity. Demographic and radiographic data; clinical outcome and perioperative complications were retrospectively analysed for patients with single-level giant thoracic disc herniations who underwent mini-thoracotomy and selective microsurgical anterior spinal cord decompression without instrumented fusion. Between 2007 and 2012, 7 consecutive patients with giant thoracic disc herniations were treated (average age of 53 years; range 45-66 years). The average canal encroachment was 73.2 % (range 40-92 %) with 5 grossly calcified discs of which 3 had transdural components. All patients had gradual myelopathic progression. The average Nurick grade was 3.5 (range 2-5). All patients were successfully treated with anterior microsurgical decompression without instrumentation. Uninstrumented fusion with rib graft was performed only in one patient with advanced degenerative changes. Average time of surgery was 337.8 min (range 220-450 min). The average length of hospital stay was 7.4 days (range 6-11 days). The average neurological status at follow-up (average 23.5 months; range 9-36 months) using the modified Nurick grading scale was 1.28. No vertebral collapse or loss of spinal alignment developed. There were no neurological complications. One patient developed an acute headache and diplopia, 10 days after surgery, following sneezing associated with a post-operative thoracic cerebrospinal fluid leakage requiring revision. Two patients suffered an approach-related complication in form of intercostal neuralgia; one was persistent. Anterior decompression using a mini-transthoracic approach provides sufficient exposure for microsurgical decompression of giant thoracic disc herniations without disrupting the stability of the spine. Microsurgical decompression without instrumentation does not appear to lead to vertebral collapse or spinal malalignment.