Minimally invasive surgical techniques in adult degenerative spinal deformity: a systematic review

Abstract

Background: Minimally invasive surgery (MIS) approaches have the potential to reduce procedure-related morbidity when compared with traditional approaches. However, the magnitude of radiographic correction and degree of clinical improvement with MIS techniques for adult spinal deformity remain undefined.

Question/purposes: In this systematic review, we sought to determine whether MIS approaches to adult spinal deformity correction (1) improve pain and function; (2) reliably correct deformity and result in fusion; and (3) are safe with respect to surgical and medical complications.

Methods: A systematic review of PubMed and Medline databases was performed for published articles from 1950 to August 2013. A total of 1053 papers were identified. Thirteen papers were selected based on prespecified criteria, including a total of 262 patients. Studies with limited short-term followup (mean, 12.1 months; range, 1.5-39 months) were included to capture early complications. All of the papers included in the review constituted Level IV evidence. Patient age ranged from 20 to 86 years with a mean of 65.8 years. Inclusion and exclusion criteria were variable, but all required at minimum a diagnosis of adult degenerative scoliosis.

Results: Four studies demonstrated improvement in leg/back visual analog scale, three demonstrated improvement in the Oswestry Disability Index, one demonstrated improvement in treatment intensity scale, and one improvement in SF-36. Reported fusion rates ranged from 71.4% to 100% 1 year postoperatively, but only two of 13 papers relied consistently on CT scan to assess fusion, and, interestingly, only four of 10 studies reporting radiographic results on deformity correction found the procedures effective in correcting deformity. There were 115 complications reported among the 258 patients (46%), including 37 neurological complications (14%).

Conclusions: The literature on these techniques is scanty; only two of the 13 studies that met inclusion criteria were considered high quality; CT scans were not generally used to evaluate fusion, deformity correction was inconsistent, and complication rates were high. Future directions for analysis must include comparative trials, longer-term followup, and consistent use of CT scans to assess for fusion to determine the role of MIS techniques for adult spinal deformity.

Fig. 1

The figure illustrates the sequence of the literature search.

Fig. 2A–B

The figure demonstrates the live intraoperative view (A) and close-up (B) of the MIS lateral approach using XLIF^® (Nuvasive, San Diego, CA, USA).

Fig. 3A–D

The patient is a 67-year-old man who initially presented to the clinic with severe back and leg pain and limited walking ability. Preoperative sagittal balance, ODI, and VAS back/leg pain were 116 mm, 50%, and 4.7, respectively. The patient was treated with the T10-L5 MIS lateral approach, L5-S1 ALIF, T12L1, L23, L34 anterior longitudinal ligament release with a hyperlordotic cage placed at those levels, and T10-S1 percutaneous pedicle screws. Two-year followup sagittal balance, ODI, and VAS were 34 mm, 2%, and 2, respectively. (A) Preoperative side-view photograph. (B) Postoperative side-view photograph. (C) Preoperative lateral radiograph. (D) Two-year followup lateral radiograph.