Midterm surgical outcomes of a short fusion strategy for adolescent idiopathic scoliosis with Lenke 5C curve

Influence of thoracolumbar kyphosis on postoperative spinal alignment in patients with Lenke type 5C adolescent idiopathic scoliosis

PURPOSE

This study aimed to examine the changes in thoracolumbar kyphosis (TLK) following correction surgery in patients with Lenke type 5C adolescent idiopathic scoliosis (AIS) and to evaluate its influence on postoperative spinal alignment and clinical outcomes.

METHODS

Sixty-six patients with Lenke type 5C AIS were included and followed up for a minimum of 5 years after surgery. First, the patients were divided into two groups according to the preoperative TLK angle (Study 1; Kyphosis and Lordosis group). The patients were further classified into two groups according to the presence or absence of postoperative changes in TLK (Study 2; Changed and Maintained groups). Finally, the outcome variables were compared between these groups and analyzed for spinal alignment and clinical outcomes.

RESULTS

In Study 1, patients demonstrated a significant kyphotic change in the Lordosis group and a significant lordotic change in the Kyphosis group postoperatively. No statistically significant differences were found between the two groups when comparing the pre- and postoperative coronal and sagittal alignment. In Study 2, there were no statistically significant differences between the Changed and the Maintained groups in each spinal alignment pre- and postoperatively. Each domain of the Scoliosis Research Society 22-item questionnaire remained unchanged at 5 years postoperation.

CONCLUSION

In many patients with Lenke type 5C AIS, TLK changed significantly and approached 0° after surgery. However, the magnitude of the preoperative TLK and the presence or absence of improvement did not affect postoperative spinal alignment. Furthermore, the patients had satisfactory clinical outcomes irrespective of TLK modification.

LEVEL OF EVIDENCE

III.

Lowest Instrumented Vertebra at L3 Versus L4 in Posterior Fusion for Moderate Lenke 5C Type Adolescent Idiopathic Scoliosis: A Case-Match Radiological Study

OBJECTIVE

To compare the radiological outcomes in Lenke 5C type patients whose lowest instrumented vertebra (LIV) was L3 or L4 in a case-match study.

METHODS

We conducted a retrospective case-match study and included 82 patients in the study. Radiological results before surgery, after surgery, and at last follow-up were recorded and analyzed in the L3 and L4 groups.

RESULTS

After matching the age, Risser's sign, sex, and main Cobb, 41 pairs of patients were enrolled in our study. The total fusion segments in the L3 group (median [interquartile range]: 5.0 [6.0-5.0]) were shorter than those in the L4 group (6.0 [6.5-6.0]). The main curve was significantly corrected after surgery in both groups, and was comparable at the last followup between groups. In addition, according to the results of Fisher precision probability test, there was no significant difference of coronal or sagittal imbalance between the 2 groups at the 2-year follow-up.

CONCLUSION

The correction in coronal and sagittal planes in L3 group and L4 group remains similar. On account of more motion segments, L3 could be an ideal choice as LIV in moderate Lenke 5C type AIS. Long-term follow-up is needed to evaluate the effect of larger compensatory lumbar-sacral curve when stopping at L3.

Association Between Lenke Classification, The Extent of Lumbar Spinal Fusion, and Health-Related Quality of Life After Instrumented Spinal Fusion for Adolescent Idiopathic Scoliosis

STUDY DESIGN

Prospective cohort study.

SUMMARY OF BACKGROUND DATA

Lenke classification is used to define the curve type in adolescent idiopathic scoliosis (AIS). The association of Lenke classification and long-term postoperative health-related quality of life (HRQoL) remains unclear.

OBJECTIVE

The purpose of this study was to assess the association between Lenke classification and HRQoL in patients who underwent spinal fusion for AIS.

MATERIALS AND METHODS

In all, 146 consecutive patients (mean age 15.1 yr) operated for AIS between 2007 and 2019 with a minimum 2-year follow-up were included. Fifty-three (36%) patients reached the 10-year follow-up. Their HRQoL was assessed with the SRS-24 questionnaire preoperatively, at six months, two years, and 10 years after surgery.

RESULTS

The preoperative major curve was the largest in Lenke 3 (mean 63 ° ) and 4 (mean 62 ° ) groups and the lowest in Lenke 5 groups (mean 48 ° , P <0.05). These curves were corrected to a mean of 15 ° with no differences between groups. We found no evidence of differences between the preoperative HRQoL scores between the Lenke groups. The self-image domain of SRS-24 was lower in patients with isolated major thoracolumbar scoliosis (Lenke 5) when compared with double-thoracic (Lenke 2) group at the two-year follow-up (mean [95% CI] 3.6 [3.3-3.9] vs. 4.3 [4.1-4.6]). The postoperative satisfaction domain was lower in Lenke 5 group when compared with main thoracic (Lenke 1) group (mean [95% CI] 3.8 [3.5-4.0] vs. 4.3 [4.2-4.5]) and Lenke 2 group (mean 4.4, 95% CI 4.2-4.6) at the two-year follow-up. The mean total score of SRS-24 at the 10-year follow-up was highest in Lenke 1 group (mean 4.06, 95% CI 3.79-4.33) and lowest in Lenke 6 group (mean 2.92, 95% CI 2.22-3.61).

CONCLUSIONS

Lenke classification and especially its curve type (major thoracic vs. major thoracolumbar scoliosis) was associated with long-term health-related quality of life after instrumented spinal fusion for AIS.

Incidence and Predictive Factors of Shoulder Imbalance After Selective Anterior Spinal Fusion Surgery in Lenke Type 5C Adolescent Idiopathic Scoliosis

Background

No study has assessed the incidence or predictors of postoperative shoulder imbalance (PSI) in patients with Lenke type 5C adolescent idiopathic scoliosis (AIS) who underwent selective anterior spinal fusion (ASF). This study evaluated the incidence and predictors of shoulder imbalance after selective ASF for Lenke type 5C AIS.

Methods

In total, 62 patients with Lenke type 5C AIS (4 men and 58 women, mean age at surgery of 15.5 ± 1.5 years) were included and divided into the following two groups according to the radiographic shoulder height (RSH) at the final follow-up: PSI and non-PSI groups. All patients in this study underwent a whole-spine radiological evaluation. Various spinal coronal and sagittal profiles on radiographs were compared between the 2 groups. The clinical outcomes were assessed using the Scoliosis Research Society (SRS)-22 questionnaires.

Results

The mean final follow-up duration was 8.6 ± 2.7 years. PSI was observed in 10 patients (16.1%) immediately after surgery; however, in the long-term follow-up period, PSI improved in 3 patients spontaneously, whereas the remaining 7 patients had residual PSI. The preoperative RSH and correction rates of the major curve immediately after surgery or at the final follow-up were significantly larger in the PSI group than in the non-PSI group (p=.001, p=.023, and p=.019, respectively). Receiver operating characteristic curve analysis indicated that the cutoff values for preoperative RSH and the correction rates immediately after surgery and at the final follow-up were 11.79 mm (p=.002; area under the curve [AUC], 0.948), 71.0% (p=.026; AUC, 0.822), and 65.4% (p=.021; AUC, 0.835), respectively. No statistically significant difference was observed in the preoperative and final follow-up SRS-22 scores in any domain between the PSI and non-PSI groups.

Conclusions

Paying attention to the preoperative RSH and avoiding excessive correction of the major curve can prevent the occurrence of shoulder imbalance after selective ASF for Lenke type 5C AIS.

Should the upper end vertebra be selected as the upper instrumented vertebra in patients with Lenke type 5C adolescent idiopathic scoliosis?

STUDY DESIGN

Retrospective study.

PURPOSE

The upper end vertebra (UEV) is often selected as the upper instrumented vertebra (UIV) in patients with adolescent idiopathic scoliosis (AIS) with Lenke type 5C curves; however, the effect of adjusting UIV selection one level toward the cranial side (UEV + 1) is unknown. Therefore, this study aimed to assess the effect of UIV extension on scoliosis correction and global alignment in patients with the UIV as the UEV and UEV + 1.

METHODS

Data of 52 patients with AIS with Lenke type 5C curves who underwent selective thoracolumbar/lumbar (TL/L) fusion with a minimum follow-up period of 2 years were retrospectively analyzed. The patients were divided according to the UIV in relation to the UEV: the UEV and UEV + 1 groups. Radiographic parameters and clinical outcomes were compared between the two groups.

RESULTS

Among the 52 patients, 24 and 28 were included in the UEV and UEV + 1 group. Baseline data showed no intergroup differences except for the UIV level. While the UEV + 1 group showed a significantly greater TL/L curve correction (72.9% vs. 62.8%, p < 0.05) and a lower UIV tilt, it showed a significantly greater absolute value of radiographic shoulder height (RSH) (- 7.9 vs. - 0.9 mm, p < 0.05) and coronal balance (- 11.0 mm vs - 4.8 mm, p < 0.05) at 2 years postoperatively. The rate of post-operative shoulder imbalance (RSH ≥ 2 cm) was significantly higher in the UEV + 1 than in the UEV group. No intergroup differences were observed in the sagittal alignment and patient outcomes between the two groups.

CONCLUSION

When the UIV was selected as the UEV + 1, correction of the TL/L curve improved; however, it increased the risk of shoulder and coronal imbalance. There is no clinical benefit observed in terms of extending the UIV to the UEV + 1; therefore, the UIV should be selected as the UEV to maintain harmonious global alignment.

LEVEL OF EVIDENCE

Level 3.

Effect of angular correction during posterior instrumentation of spinal fractures on postoperative outcomes and quality of life

BACKGROUND

Posterior instrumentation using pedicle screws and rods is the most commonly used technique for the treatment of thoracolumbar fractures of the spine. The procedure aims to restore the neurologic and biomechanical functions of the spine and allows for early mobilization and rapid reintegration into society. It is unclear whether the magnitude of correction has an effect on postoperative outcomes.

OBJECTIVE

We aimed to determine whether the magnitude of sagittal angular correction during posterior instrumentation of the spine had an effect on postoperative quality of life, pain and function outcomes as measured using the EQ5D-3L and the Core Outcome Measures Index (COMI) instruments. We also aimed to quantify the correlation between EQ5D-3L and COMI scores.

METHODS

We analyzed the pre- and postoperative radiographs of 52 patients who underwent percutaneous pedicle screw placement for thoracolumbar fractures, as well as their self-reported EQ5D-3L and COMI quality of life, pain and functional outcome scores. Regression models were constructed to estimate the effect that the magnitude of Cobb angle correction had on postoperative outcomes. We also estimated the correlation between EQ5D-3L and COMI scores.

RESULTS

The median EQ5D-3L TTO score was 0.9 (range, -0.1 to 1). The median COMI score was 3.1 (range, 0 to 10). There was no significant effect of the magnitude of correction on EQ5d-3L TTO scores (p= 0.3379; R= 0.36) or on COMI scores (p= 0.3379; R= 0.15). Age and bone mineral density were not found to be significant predictors of outcome (p= 0.05). There was a strong correlation between the EQ5D-3L TTO and COMI scores (r=-0.62).

CONCLUSION

The magnitude of Cobb angle correction during pedicle screw instrumentation of thoracolumbar fractures did not influence quality of life, pain or function outcomes. There was good correlation between EQ5D-3L TTO scores and COMI scores.

C-Arm-Free Anterior Correction for Adolescent Idiopathic Scoliosis (Lenke Type 5C): Analysis of Early Outcomes and Complications

BACKGROUND

Computer-assisted spinal surgery as a technique for reducing radiation exposure to the operating staff and the complications of spinal deformity are receiving considerable attention. However, no technical reports have described the technique for navigating anterior correction of adolescent idiopathic scoliosis without C-arm fluoroscopy. The purpose of this study was to evaluate the efficacy and safety of this new C-arm-free anterior correction for scoliosis.

METHODS

This study investigated 38 consecutive patients with Lenke type 5C curves who underwent selective lumbar or thoracolumbar fusion, comprising 26 patients with conventional anterior correction surgery, and 12 patients with C-arm-free navigation surgery. The 2 groups were evaluated immediately postoperatively and at the 2-year follow-up.

RESULTS

No vascular injuries, screw malpositioning, or major complications were associated with the surgical procedure in either group. Correction rates of the lumbar curve were satisfactory with no significant difference between groups (mean, 82.6% ± 5.7% vs. 80.7% ± 10.2%, respectively). However, mean time for fluoroscopy in group C was 133 ± 9.5 seconds (P < 0.0001). No significant differences in intraoperative blood loss (642 ± 123 mL vs. 731 ± 222 mL, respectively) or surgical time (251 ± 13 min vs. 301 ± 38 min, respectively) were seen between groups. Mean final follow-up Scoliosis Research Society Outcomes Questionnaire (SRS-22) was also excellent for both group C (4.2 ± 0.19) and group N (4.3 ± 0.20).

CONCLUSIONS

C-arm-free anterior correction offers safe, effective surgery for adolescent idiopathic scoliosis. The advantage of this new technique is no radiation exposure for medical staff at centers performing large numbers of spinal procedures.