Clinical Results of First Japanese Experience in Combined OLIF and MIS Posterior Approach for Adult Spinal Deformities

Presented at SMISS Annual Forum 2014
By Yoshihisa Kotani MD, PhD
With Ivan Gonchar MD, Yuki Matsui MD, Takuji Miyazaki MD, Toshiyuki Kasemura MD,

Disclosures: Yoshihisa Kotani MD, PhD B; L&K Biomed. Ivan Gonchar MD None, Yuki Matsui MD None, Takuji Miyazaki MD None, Toshiyuki Kasemura MD None,

Introduction:
Our MIS deformity strategy includes simultaneous circumferential MIS (OLIF and MIS-PF) for minimum global imbalance, and two-stage AP surgeries for global imbalance cases. The second stage MIS-PF included percutaneous PF(CBT, PPS), Hybrid PF and Full-open PF, which were determined according to global balance and pelvic parameters after 1^st stage OLIF.

Aims/Objectives:
We report the clinical results of first Japanese experience in combined OLIF and MIS posterior approach for adult spinal deformities.

Methods:
28 patients underwent MIS deformity correction surgeries in this initial series. The average age was 76 yrs (61-84). There were 14 degenerative scoliosis, 10 adult scoliosis and 4 kyphosis. Preoperative complaints were the difficulty in standing with either severe LBP or spinal imbalance, and pain or numbness in lower extremities. 10 pts had nerve root disturbance preoperatively. The surgical procedures included simultaneous circumferential MIS, and two-stage cMIS, Hybrid PF and full-open PF according to global balance and pelvic parameter evaluation on post OLIF standing X-rays. The surgical time, intraoperative bleeding, and surgical complications were reviewed. The preop and F-up Cobb angles, CVA, SVA, LL, TK, PI, SS, PI-LL were measured and calculated. The patient-based clinical outcomes were assessed with Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ), Oswestry Disability Index (ODI) and VAS scoring.

Results:
Average fixed segments were 7.4 (2-16). The average surgical time was 212 and 244 min in anterior and posterior approach, respectively. The intraoperative bleeding was 192 and 269 ml, respectively. The average preoperative Cobb angles of 35 deg were corrected to 11 deg at F-up. The average CVA and SVA were corrected from 26 and 73mm to 8 and 36mm, respectively (P<0.05). The average LL was corrected from 21 to 29 deg at F-up. The average PI-LLs were improved from 35 to 28 deg at F-up. The surgical complications included two screw pullout requiring cephalad fusion extension, four transient motor weakness, and 1 vertebral body fracture after initial OLIF procedure. The JOABPEQ, ODI and VAS values improved specifically in terms of LBP and Gait scores at F-up.

Conclusions:
The Japanese first clinical results of combined OLIF and MIS-PF were acceptable, however, the preoperative estimation whether single stage or two-stage surgical strategy could be required was still unclear. So far, we set the cut-off points at CVA>40mm, SVA>70mm, PI-LL>40 for the safety standpoint. However, the further larger study will be required to clarify this point.