Prevalence and Key Radiographic Spinal Malalignment Parameters Associated with the Risk of Pulmonary Function Impairment in Patients Treated Surgically to Correct Adult Spinal Deformity

Comparative Study for Characteristics of Locomotive Syndrome in Patients with Lumbar Stenosis and Adult Spinal Deformity

INTRODUCTION

The differential diagnoses of lumbar spinal stenosis (LSS) and adult spinal deformity (ASD) have been demonstrated primarily using sagittal radiographic spinopelvic parameters. However, it is more important to know the differences in the characteristic clinical symptoms to make accurate treatment decisions. Recently, the relationship between spinal disease and Locomotive Syndrome (LS) has been reported. Additionally, the Geriatric Locomotive Function Scale-25 (GLFS-25) was reported to be a useful scale to evaluate disease severity and characteristic clinical symptoms in spinal disease.

METHODS

Sixty-nine consecutive patients with ASD and 196 patients with LSS who underwent spinal surgery were included. Locomotive dysfunction was evaluated using the GLFS-25 questionnaire and physical performance tests including the two-step test and the stand-up test, measured preoperatively. The correlations between sagittal spinopelvic parameters of ASD and LS were examined.

RESULTS

All subjects with lumbar degenerative disease in the present study were diagnosed with LS preoperatively. The severity of LS in patients with LSS and ASD were statistically similar. GLFS-25 scores in the mobility and community domain were similarly poor in both groups. Several scores in the domestic life and self-care domains were significantly worse in the ASD group. Question 20 of the GLFS-25, related to load-bearing tasks and housework, was significantly associated with a large pelvic incidence in ASD patients.

CONCLUSIONS

Lumbar degenerative disease requiring surgery severely affects the LS of older people. ASD patients had more difficulty with load-bearing tasks and housework such as cleaning the yard, carrying heavy bedding, dressing, and bathing compared to LSS patients.

Preoperative Radiographic Evaluation of Thoracic Flexibility and Compensation for Adult Spinal Deformity Surgery. How to Select Optimal Upper Instrumented Vertebra to Prevent Proximal Junctional Kyphosis

STUDY DESIGN

Retrospective study of a cohort of consecutive patients.

OBJECTIVE

The aim of this study was to clarify the usefulness and value of the difference in thoracic kyphosis (ΔTK) angle in various positions by imaging the patient standing, prone, and supine to evaluate TK flexibility and compensation, and to establish optimal radiography to determine an appropriate thoracic level for upper instrumented vertebra (UIV) because a strategy to select an appropriate level to avoid proximal junctional kyphosis (PJK) remains elusive.

SUMMARY OF BACKGROUND DATA

Postoperative reciprocal progression of TK is a significant risk factor for PJK. However, how to predict and prevent postoperative reciprocal progression of TK remains unclear. We hypothesized that preoperative evaluation of both TK flexibility and compensation is essential to predict PJK and determine the UIV level.

METHODS

We included 144 consecutive patients with adult spinal deformity (ASD), ≥2 years' follow-up, and UIV Th9-11 in this retrospective cohort study. TK was measured from images with patients standing, prone, and supine. Supine ΔTK was calculated as standing TK- supine TK. Prone ΔTK was calculated as standing TK - prone TK. Receiver-operating characteristic (ROC) curves were analyzed to determine the thresholds of supine ΔTK and prone ΔTK for PJK occurrence.

RESULTS

PJK was observed in 64 of 144 (44%) patients 2 years postoperatively. Prone and supine ΔTKs were significantly larger in patients with PJK. A significant positive correlation between prone ΔTK and supine ΔTK was observed. When data from patients with and without PJK were plotted separately, a significantly higher proportion of patients with PJK had large prone and supine ΔTKs. The cutoff values of prone and supine ΔTKs for PJK risk were determined using ROC curve analysis.

CONCLUSION

Because of their significantly high risk for PJK, in patients with ASD and prone ΔTK >11.5° and supine ΔTK >18.5°, the upper-thoracic spine should be considered for UIV.Level of Evidence: 3.