Comparison of minimally invasive surgery with standard open surgery for vertebral thoracic metastases causing acute myelopathy in patients with short- or mid-term life expectancy: surgical technique and early clinical results
Authors: Miscusi Massimo , Polli Filippo Maria , Forcato Stefano , Ricciardi Luca , Frati Alessandro , Cimatti Marco , De Martino Luca , Ramieri Alessandro , Raco Antonino 
Published: February 2015

OBJECT
Spinal metastasis is common in patients with cancer. About 70% of symptomatic lesions are found in the thoracic region of the spine, and cord compression presents as the initial symptom in 5%–10% of patients. Minimally invasive spine surgery (MISS) has recently been advocated as a useful approach for spinal metastases, with the aim of decreasing the morbidity associated with more traditional open spine surgery; furthermore, the recovery time is reduced after MISS, such that postoperative chemotherapy and radiotherapy can begin sooner.

METHODS
Two series of oncological patients, who presented with acute myelopathy due to vertebral thoracic metastases, were compared in this study. Patients with complete paraplegia for more than 24 hours and with a modified Bauer score greater than 2 were excluded from the study. The first group (n = 23) comprised patients who were prospectively enrolled from May 2010 to September 2013, and who were treated with minimally invasive laminotomy/laminectomy and percutaneous stabilization. The second group (n = 19) comprised patients from whom data were retrospectively collected before May 2010, and who had been treated with laminectomy and stabilization with traditional open surgery. Patient groups were similar regarding general characteristics and neurological impairment. Results were analyzed in terms of neurological recovery (American Spinal Injury Association grade), complications, pain relief (visual analog scale), and quality of life (European Organisation for Research and Treatment of Cancer [EORTC] QLQ-C30 and EORTC QLQ-BM22 scales) at the 30-day follow-up. Operation time, postoperative duration of bed rest, duration of hospitalization, intraoperative blood loss, and the need and length of postoperative opioid administration were also evaluated.

RESULTS
There were no significant differences between the 2 groups in terms of neurological recovery and complications. Nevertheless, the MISS group showed a clear and significant improvement in terms of blood loss, operation time, and bed rest length, which is associated with a more rapid functional recovery and discharge from the hospital. Postoperative pain and the need for opioid administration were also significantly less pronounced in the MISS group. Results from the EORTC QLQ-C30 and QLQ-BM22 scales showed a more pronounced improvement in quality of life at follow-up in the MISS group.

CONCLUSIONS
In the authors' opinion, MISS techniques should be considered the first choice for the treatment for patients with spinal metastasis and myelopathy. MISS is as safe and effective for spinal cord decompression and spine fixation as traditional surgery, and it also reduces the impact of surgery in critical patients. However, further studies are needed to confirm these findings.