Adolescent Idiopathic Scoliosis: Is the Feasible Option of Minimally Invasive Surgery using Posterior Approach?

The purpose of this systematic review and meta-analysis is to perform a systematic review and meta-analysis of previous studies on minimally invasive scoliosis surgery (MISS) in adolescents with idiopathic scoliosis (AIS). Some data on MISS in AIS compared with conventional open scoliosis surgery (COSS) are conflicting. A systematic literature search was conducted in Medline, Embase, and Cochrane Library, including studies reporting outcomes for MISS in AIS. The meta-analysis compared the operative, radiological, and clinical outcomes and complications between MISS and COSS in patients with AIS. Of the 208 records identified, 15 nonrandomized studies with 1,369 patients (reviews and case reports are excluded) were included in this systematic review and meta-analysis. The mean scale was 6.1, and eight of the 15 included studies showed satisfactory quality using the Newcastle-Ottawa scale. For operative outcomes, MISS had significant benefits in terms of estimated blood loss (standard mean difference [SMD], -1.87; 95% confidence interval [CI], -2.94 to -0.91) and hospitalization days (SMD, -2.99; 95% CI, -4.45 to -1.53) compared with COSS. However, COSS showed significantly favorable outcomes for operative times (SMD, 1.71; 95% CI, 0.92-2.51). No significant differences were observed in radiological outcomes, including Cobb's angle of the main curve and thoracic kyphosis. For clinical outcomes, MISS showed significant benefits on the visual analog scale score (SMD, -0.91; 95% CI, -1.36 to -0.47). The overall complication rates of MISS were similar to those of COSS (SMD, 0.96; 95% CI, 0.61-1.52). MISS using the posterior approach provides equivalent radiological and clinical outcomes and complication rates compared with COSS. Considering the lower estimated blood loss, shorter hospitalization days, and longer operative times in MISS, COSS is still the mainstay of surgical treatment in AIS; however, MISS using the posterior approach is also one of the surgical options of choice in the case of moderate AIS.

Fusion rates based on type of bone graft substitute using minimally invasive scoliosis surgery for adolescent idiopathic scoliosis

BACKGROUND

Minimally invasive scoliosis surgery (MISS) is currently introduced on novel technique for surgical treatment of adolescent idiopathic scoliosis (AIS). This study is aimed to evaluate the efficacy of facet fusion in MISS compared to posterior fusion in conventional open scoliosis surgery (COSS) and compare facet fusion rates based on three bone graft substitutes in MISS for adolescent idiopathic scoliosis (AIS).

METHODS

Eighty six AIS patients who underwent scoliosis surgery were divided into two groups: the COSS group and the MISS group. COSS was performed through posterior fusion with allograft. MISS was applied via facet fusion with three bone graft substitutes. The MISS group was further divided into three subgroups based on graft substitute: Group A (allograft), Group B (demineralized bone matrix [DBM]), and group C (demineralized cancellous bone chips). Fusion rate was measured using conventional radiographs to visualize loss of correction > 10°, presence of lysis around implants, breaks in fusion mass, and abnormal mobility of the fused segment.

RESULTS

The fusion rates showed no significant difference in COSS and MISS groups (p = 0.070). In the MISS group, the fusion rates were 85, 100, and 100% in groups A, B, and C, respectively, with no significant difference (p = 0.221). There were no statistical differences between groups A, B, and C in terms of correction rate, fusion rate, and SRS-22 scores (p > 0.05).

CONCLUSIONS

The facet fusion in MISS showed comparable to posterior fusion in COSS with regard to radiological and clinical outcomes. Furthermore, the type of graft substitute among allograft, DBM, and demineralized cancellous bone chips did not affect facet fusion rate or clinical outcomes in MISS. Therefore, MISS showed comparable fusion rate (with no influences on the type of graft substitute) and clinical outcomes to those of COSS in the surgical treatment of AIS.

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.

Minimally invasive scoliosis surgery for adolescent idiopathic scoliosis using posterior mini-open technique

The purpose of this study aimed to analyze and evaluate the radiologic and clinical outcomes of minimally invasive scoliosis surgery (MISS) for correcting adolescent idiopathic scoliosis (AIS) using the mini-open technique. Thirty-four AIS patients who underwent MISS using the mini-open technique for deformity correction. Using two to four 3-centimeter-long skin incisions (mini-open) and tubular retractors, we performed screw fixations, rod assembly, rod derotation maneuver (RD), and bone graft. For thoracoplasty, four to six ribs were resected using the same incisions. Correction was attempted using rod translation and RD maneuvers. Radiological outcomes and clinical outcomes (SRS-22) were evaluated. Mean preoperative Cobb's angle was 61.3° and curve flexibility (major curve) was 26.1%. This angle was corrected to 21.6° with a correction rate of 65.2% (P < 0.001). The coronal balance was not changed significantly. Sagittal vertical axes were corrected from -3.5 mm to 8.6 mm (-22 to 36.3 mm) (P = 0.009). Thoracic kyphosis angles and lumbar lordosis angles were not changed significantly but the values were within normal range. Each score of self-image in the SRS-22 questionnaire as well as the total score were improved significantly (P < 0.001). In conclusion, the MISS for correcting AIS using the mini-open technique showed comparable radiologic and clinical outcomes with fewer complications in patients with non-rigid scoliosis with Cobb's angle between 50° and 80°. Long-term results of this novel MISS using the mini-open technique could further strengthen the rationale for adopting this technique for curve correction in selected cases of AIS.

Comparative Analysis of Radiologic and Clinical Outcomes Between Conventional Open and Minimally Invasive Scoliosis Surgery for Adolescent Idiopathic Scoliosis

OBJECTIVE

To compare radiologic and clinical outcomes between conventional open scoliosis surgery (COSS) and minimally invasive scoliosis surgery (MISS) for adolescent idiopathic scoliosis (AIS).

METHODS

Forty-nine AIS patients who underwent scoliosis surgery were retrospectively analyzed in 2 groups: the COSS (n = 25) and MISS (n = 24) groups. COSS procedures used monoaxial screws with a rod derotation (RD) maneuver through a long linear incision. In the MISS group, the technique was applied via 2 or 3 incisions of about 3 cm in length, and a muscle-splitting approach and correction were performed using polyaxial screws with an RD maneuver.

RESULTS

In the analysis of the coronal (Cobb angle of the main curve) and sagittal planes (thoracic kyphosis and lumbar lordosis), correction was significantly superior in the COSS group (all P values >0.05). However, in the coronal balance and spinal vertical axis, which are global balance factors, there were no significant differences between the groups (P = 0.331 and P = 0.750). There were significant differences between the COSS and MISS groups in terms of mean hospital stay duration (P < 0.001), operative time (P < 0.001), estimated blood loss (P < 0.001), and scar length (P < 0.001). There was no significant difference in the various Scoliosis Research Society-22 questionnaire scores between the groups.

CONCLUSIONS

Although COSS for AIS was superior for correcting the main curve, MISS was associated with shorter hospitalization, less blood loss, and superior cosmesis as well as providing adequate correction in both the coronal and sagittal planes.

Safety and effectiveness of minimally invasive scoliosis surgery for adolescent idiopathic scoliosis: a retrospective case series of 84 patients

PURPOSE

The aim of this study was to retrospectively evaluate a prospective series of patients with adolescent idiopathic scoliosis (AIS) who were treated with minimally invasive scoliosis surgery (MISS) technique with a minimum follow-up more than 1 year.

MATERIALS AND METHODS

We retrospectively analyzed the prospectively collected data of 84 patients with AIS treated with MIS technique using two or three coin hole size incisions and a muscle-splitting approach. The clinical and radiological data such as the correction of deformity, coronal and sagittal profile and record of the perioperative morbidity of the patients were analyzed.

RESULTS

The mean primary Cobb angle was corrected from 59.8° preoperatively to 18.6° postoperatively with a mean correction of 68.9% (p < 0.001). The mean kyphosis at T2 to T12 was maintained within normal range with an increase from 31.2° preoperatively to 35.3° postoperatively (p < 0.001). The 30-day perioperative complication rate was 7.14% with one deep infection and five cases of hemothorax. The mean operation time was 312.8 min; mean estimated blood loss was 846.6 ml (range 420-2800); and mean length of stay was 8.5 days (range 5 to 14). All data of postoperative SRS-22 questionnaire were significantly improved (p < 0.001).

CONCLUSION

MISS used for AIS provides adequate correction in both planes and acceptable rate of perioperative complications, with a low estimated blood loss and short length of stay. Considering all the positives, the application of MISS technique for AIS seems meaningful and can become a valid alternative to posterior approach in the routine use. These slides can be retrieved under Electronic Supplementary Material.

Delayed presentation of infected common iliac artery pseudoaneurysm caused by malpositioned pedicle screw after minimally invasive scoliosis surgery

PURPOSE

To report delayed onset common iliac artery perforation and infected pseudoaneurysm caused by malpositioned pedicle screw after minimally invasive scoliosis surgery (MISS).

METHODS

A 21-year-old female was referred to our hospital with a 1-week history of abrupt right-sided low back pain, lower abdominal pain, and fever with a history of MISS using cannulated pedicle screws 18 months earlier. Paravertebral arterial erosion with pseudoaneurysm and retroperitoneal and paraspinal abscess were suspected.

RESULTS

We performed resection of the pseudoaneurysm, vascular repair of right common iliac artery by angioplasty with a bovine patch and removal of implant. At 6 months after the last surgery, she had no limitations or problems in her daily activities with no recurrence of low back pain, abdominal pain, or fever as well as without loss of deformity.

CONCLUSIONS

Our case showed that misplaced pedicle screws can cause potentially fatal complications, such as infected pseudoaneurysm, even in the late postoperative period.