Clinical appearance and reliability in visual assessment after in situ fusion for high-grade isthmic spondylolisthesis.

PURPOSE: The current literature on clinical appearance after surgery for high-grade spondylolisthesis is inconclusive. The few long-term comparative studies on surgical reduction versus in situ fusion report contradictory findings concerning appearance-related issues. The purpose of the current study was to evaluate and quantify clinical appearance three decades after in situ fusion for high-grade isthmic spondylolisthesis. METHODS: The Scoliosis Research Society (SRS)-22r questionnaire, digital photographs and standing lateral radiographs were used to evaluate clinical appearance for 22 patients three decades after in situ fusion for high-grade spondylolisthesis. The appearance was assessed by two spine surgeons, by the patient themselves, and by quantification of cosmesis relevant radiographic variables including pelvic parameters and sagittal balance. RESULTS: The surgeon inter- and intraobserver reliability of the photographic evaluation of the trunk deformity was at most moderate (Cohen's kappa 0.5). Correlation analysis revealed at most medium correlation between radiographic outcome and self-rated (SRS-22r) self-image (Spearman's rank correlation coefficient 0.3). The agreement between patient and surgeon-rated trunk appearance was poor (Cohen's kappa 0.2). CONCLUSIONS: Photographic evaluation of the trunk deformity in high-grade spondylolisthesis is unreliable. There were only weak correlations between patient self-assessed trunk appearance and radiographic parameters. The results reflect the pronounced subjectivity of cosmesis, and that the trunk deformity in high-grade spondylolisthesis is not easily observed. LEVEL OF EVIDENCE: IV.

Adjacent segment disk degeneration three decades after fusion without attempted reduction for high-grade isthmic spondylolisthesis.

STUDY DESIGN: Observational study. OBJECTIVES: To evaluate adjacent segment disk degeneration (ASD) after fusion without attempted reduction at a young age for high-grade isthmic spondylolisthesis. The clinical relevance of ASD remains unclear. Previous studies have shown that spinal fusion is associated with increased ASD but without influence on clinical outcome. Since high-grade spondylolisthesis is a severe kyphotic deformity, one could hypothesize that fusion without attempted reduction in young patients leads to accelerated adjacent segment disk degeneration in adult life. METHODS: Anterior and posterior disk heights were evaluated on supine radiographs of the spine 8 years and 29 years after fusion without attempted reduction for high-grade spondylolisthesis and also on standing radiographs 8 years and 33 years after surgery. Pelvic parameters were evaluated on standing radiographs obtained 33 years after surgery. Health-related quality of life was evaluated with the Scoliosis Research Society (SRS)-22r questionnaire. RESULTS: One segment above fusion the anterior disk height significantly decreased on standing radiographs. Two segments above the fusion, the anterior disk height significantly decreased on supine as well as on standing radiographs. The largest reduction was found two segments above the fusion where the disk height was reduced from 33 to 28% of anterior vertebral height between the measurements at mean 8 years and mean 33 years after surgery. There were no statistically significant decreases in posterior disk heights in any measurement. The disk height showed a moderate negative correlation to PT. There was no correlation between disk height reduction and SRS-22r outcome. CONCLUSIONS: In our long-term follow-up of fusion without attempted reduction for high-grade spondylolisthesis in young patients, we found only a minor but statistically significant reduction in adjacent segment disk height which had no apparent impact on clinical outcome. LEVEL OF EVIDENCE: Level IV.

Sagittal Balance and Health-Related Quality of Life Three Decades After in Situ Arthrodesis for High-Grade Isthmic Spondylolisthesis.

BACKGROUND: This case series of consecutive patients evaluated sagittal balance and health-related quality of life (HRQoL) 3 decades after in situ arthrodesis for high-grade isthmic spondylolisthesis. METHODS: Global sagittal balance, pelvic parameters, and compensatory mechanisms were evaluated on standing lateral radiographs of the spine and pelvis for 28 of 39 consecutive patients, 28 to 41 years after in situ arthrodesis for high-grade L5 to S1 spondylolisthesis. The mean age at surgery was 14 years (range, 9 to 24 years), and the mean age at the time of follow-up was 48 years (range, 39 to 59 years). A subset of the radiographic parameters was compared with the corresponding data from an 8-year follow-up examination of the same patients. HRQoL was evaluated with the Scoliosis Research Society (SRS)-22r questionnaire. RESULTS: We found that 3 of the 28 patients had a global sagittal imbalance (T1 spinopelvic inclination of >0°). Signs of compensatory mechanisms, such as reduced thoracic kyphosis and pelvic retroversion, were frequent. There was a significant decrease in sacral slope compared with 8-year follow-up data (p = 0.01). The median SRS-22r subscore was on the same level as Swedish normative data. We found no association between radiographic parameters and SRS-22r outcome. CONCLUSIONS: Three decades after in situ arthrodesis for high-grade spondylolisthesis, radiographic signs of noncompensated sagittal imbalance were observed in only a few individuals. The patients had normal SRS-22r scores. There was no association between any radiographic parameter and SRS-22r outcome. The findings are relevant in the controversial discussion on whether to perform a reduction procedure to treat high-grade spondylolisthesis. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Comparison of Cobb angles in idiopathic scoliosis on standing radiographs and supine axially loaded MRI.

STUDY DESIGN: Prospective, patient controlled. OBJECTIVE: To compare Cobb angles in idiopathic scoliosis between standing radiographs and a nonradiographic procedure. SUMMARY OF BACKGROUND DATA: Repeated radiographic examinations at young age may increase the risk for breast cancer in adulthood. MRI images the spine satisfactorily but is cumbersome in standing. A harness supplying axial load to a lying subject simulates the standing radiograph appearance of the lumbar spine. METHODS: Thirty patients with idiopathic scoliosis greater than 20 degrees performed a routine posteroanterior and lateral standing thoracolumbar spine radiograph and an MRI in supine position without and with axial loading. RESULTS: Mean Cobb angle for the major curve was 31 degrees on standing radiographs, 23 degrees on nonloaded supine MRI, and 31 degrees on supine loaded MRI. Axially loaded, compared with nonloaded, MRI increased the Cobb angle by 8 degrees. The mean difference between standing radiograph and supine axially loaded MRI was 0 degrees, with an intermethodologic variation(s) of 3.4 degrees. Radiographic and MRI (axially loaded) Cobb angles correlated positively (r = 0.78). CONCLUSIONS: Axial loading on supine MRI produces coronal Cobb angles similar to standing radiographs. This is a way to acquire reliable Cobb angles without radiation in the monitoring of idiopathic scoliosis.