Table 2.

Minimal access spine surgery outcomes. MOT: Mean operating time; LOS: Length of stay; NI: Neurological improvement rate; PA: Pain alleviation rate; CR: Complications rate; MBL: Mean blood loss, SVR: 2-year survival rate.

Study	Design and procedure	Outcome results
Mühlbauer et al. [27], 2000	Retrospective case series (n = 5) of patients undergoing lumbar corpectomy and anterior reconstruction via MASS in the setting of osteoporotic or malignancy-related compression fractures	MOT: 6 hours NI: All patients experienced neurological improvement and were ambulatory at followup (6 mo to 1 yr) PA: All patients experienced pain relief. 40% of patients did not utilize analgesics at 1-year followup CR: Segmental vessel nick via a high-speed drill. Bleeding was adequately controlled MBL: 1120 mL
Huang et al. [23], 2006	Retrospective analysis (n = 46) comparing MASS (n = 29) to standard thoracotomy (ST) (n = 17) in the management of thoracic spinal metastasis	MOT: MASS = 179 mins versus ST = 180 mins; P = .54 % Requiring 2-day ICU stay: MASS = 6.9% versus ST = 88%, P ≤ .001 NI: Reacquisition of ambulation postoperatively; MASS = 70.8% versus ST = 69.2%, P = .6 SVR: MASS = 27.4 mo versus ST = 24.8 mo, P = .68 CR: MASS = 24% versus ST = 29% MBL: MASS = 1,100 mL versus ST = 1,162 mL, P = .63
Deutsch et al. [28], 2008	Retrospective case series (n = 8) of patients undergoing MASS posterolateral vertebrectomy and decompression for the management of thoracic spinal metastasis	MOT: 2.2 hours LOS: 4 days NI: 62.5% of patients PA: 62.5% of patients CRs: none MBL: 227 mL
Kan and Schmidt [29], 2008	Retrospective case series (n = 5) of patients undergoing MASS anterior corpectomy and decompression for the management of thoracic spinal metastasis	MOT: 4.3 hours LOS: 6.25 NI: All patients experienced neurological improvement PA: All patients experienced pain alleviation CR: none MBL: 610 mL
Payer and Sottas [30], 2008	Retrospective case series (n = 11) analyzing operative outcomes of MASS conducted with the SynFrame (Stratec Medical, Obendorf, Switzerland) table mounted retractor in the setting of thoracic metastatic spine disease	MOT: 188 mins NI: All patients neurologically intact, at presentation remained intact and 91% of patients with preoperative deficit experienced neurological improvement CR: 18% (2/11; one dural tear and one superficial wound infection) MBL: 711 mL
Taghva et al. [31], 2010	Case report of a man undergoing vertebrectomy and expandable cage reconstruction for the management of metastatic lung adenocarcinoma localized to the thoracic spine	MOT: 7 hours LOS: 5 days NI: Patient experienced myelopathy relief and was ambulatory on postoperative day 1 PA: at 9-month followup, patient remained back pain-free with no use of analgesic medications CR: none MBL: 1200 mL