Posterior minimally invasive scoliosis surgery versus the standard posterior approach for the management of adolescent idiopathic scoliosis: an updated meta-analysis

BACKGROUND: Surgical management of adolescent idiopathic scoliosis (AIS) can be performed using standard posterior spinal fusion (PSF) or with a posterior minimally invasive approach. Minimally invasive scoliosis surgery (MISS) has several theoretical advantages, such as less tissue dissection, less blood loss, and earlier recovery. However, the difference in safety and effectiveness between MISS and PSF still needs to be clarified. This updated meta-analysis aimed to compare the outcomes of MISS and standard PSF for the management of AIS. METHODS: A comprehensive literature search of PubMed, EMBASE, MEDLINE, and Cochrane Library without time restriction was performed to identify relevant studies. MISS and PSF were compared in terms of radiographic parameters, estimated blood loss (EBL), blood transfusion rate, operative time (ORT), length of hospital stay (LOS), overall Scoliosis Research Society-22 (SRS-22) score, postoperative pain, and complication rate. RESULTS: A total of seven studies comprising 767 patients (329 MISS and 438 PSF) with AIS were included. MISS and PSF yielded comparable deformity correction at the last follow-up. There were no significant differences in the overall SRS-22 scores or complication rates between the groups. Nevertheless, greater restoration of thoracic kyphosis (WMD, 2.98; 95% CI 0.58 to 5.37, P = 0.015), less EBL (WMD, −218.76; 95% CI −256.41 to −181.11, P < 0.001), a lower blood transfusion rate (RR, 0.31; 95% CI 0.20 to 0.48, P < 0.001), a shorter LOS (WMD, −1.48; 95% CI −2.48 to −0.48, P = 0.004), less postoperative pain (WMD, 0.57; 95% CI 0.16 to 0.98, P = 0.006), and a longer ORT (WMD, 84.85; 95% CI 33.30 to 136.40, P = 0.001) were observed in the MISS group. CONCLUSION: Despite its inherent technical challenges, MISS is a feasible and effective alternative to standard PSF for AIS patients with moderate and flexible curves. MISS was associated with adequate deformity correction, better restoration of sagittal alignment, less EBL, fewer transfusions, shorter LOS, and better pain management compared to PSF. Further research is required to determine the detailed indications for the MISS procedure. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13018-022-02954-4.