Spondylolisthesis: intraobserver and interobserver reliability with regard to the measurement of slip percentage

Reference Data for Diagnosis of Spondylolisthesis and Disc Space Narrowing Based on NHANES-II X-rays

Robust reference data, representing a large and diverse population, are needed to objectively classify measurements of spondylolisthesis and disc space narrowing as normal or abnormal. The reference data should be open access to drive standardization across technology developers. The large collection of radiographs from the 2nd National Health and Nutrition Examination Survey was used to establish reference data. A pipeline of neural networks and coded logic was used to place landmarks on the corners of all vertebrae, and these landmarks were used to calculate multiple disc space metrics. Descriptive statistics for nine SPO and disc metrics were tabulated and used to identify normal discs, and data for only the normal discs were used to arrive at reference data. A spondylolisthesis index was developed that accounts for important variables. These reference data facilitate simplified and standardized reporting of multiple intervertebral disc metrics.

Spontaneous improvement of olisthetic scoliosis in children following lumbosacral fusion for high-grade spondylolisthesis: A report of four new cases and systematic review of the literature

Background

The study aim was to present four new well-documented cases of spontaneous improvement of olisthetic scoliosis and to analyze well-documented cases from the literature.

Methods

Surgical log search and systematic review were conducted. Inclusion criteria were (1) age less than 18 years, (2) symptomatic high-grade (≥50%) spondylolisthesis, (3) scoliosis ≥20o, (4) primary surgical treatment via lumbosacral fusion, (5) complete x-rays, and (6) minimum 1-year radiographic follow-up or until curve resolution.

Results

A total of 13 patients with average age of 13.9 years were included in the study, 4 from the authors' surgical logs and 9 from the literature. Slip percentage of L5-S1 ranged from 51% to 95%. Olisthetic curve magnitude averaged 34.6° (range: 20°-45°) with majority (8/13) demonstrating long thoracic curves with lateral trunk shift. All but one of these were apex right with rightward trunk shift. The remainder of the curves were isolated lumbar curves, with an apex left morphology without trunk shift. Eleven of the 13 patients showed curve improvement following isolated lumbosacral fusion. Three patients experienced a decrease in curve magnitude of 12°-28° and eight patients enjoyed complete resolution (≤10°) of their scoliosis.

Conclusion

The current study summarizes 13 well-documented cases of olisthetic scoliosis (4 new cases and 9 from the literature) that associated with symptomatic high-grade spondylolisthesis. All were treated via a primary posterior lumbosacral fusion strategy. Eleven of the 13 curves showed spontaneous improvement (8 complete resolution of scoliosis) following their lumbosacral surgery.

Level of evidence

Therapeutic level IV.

A ball-slide-type interbody distractor is effective in posterior reduction and internal fixation for patients with mid- to high-grade isthmic spondylolisthesis enrolled in a randomized clinical trial

STUDY DESIGN

Clinical and radiographic results of a randomized, controlled, double-blind clinical trial OBJECTIVE:: To investigate the clinical applicability of a ball-point slide-type interbody distractor in posterior reduction and internal fixation for mid- to high-grade isthmic spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Posterior reduction and internal fixation is the effective treatment for spondylolisthesis. However, for the mid and high-grade isthmic spondylolisthesis patients with the conditions of vertebral osteoporosis and extremely narrow intervertebral space, the reduction is difficult; post-surgery intervertebral space height lost becomes serious; the fracture and loosening rate of fixation system is higher. No study regarding the prevention of these adverse outcomes in this technique is reported.

METHODS

A total of 59 patients of mid and high-grade isthmic spondylolisthesis were randomly divided into random groups (investigational group and control group) applying simple randomized method in this study. In addition, 30 patients received posterior reduction and internal fixation as control. Twenty-nine patients received posterior reduction and internal fixation by ball-point slide-type interbody distractor were assigned to the investigational group. X-ray examination was performed before and after operation. The degree of reduction, height of intervertebral space were compared. The preoperative and postoperative Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) were evaluated. Additionally, rate of the fixation system fracture was also assessed.

RESULTS

Before treatment, there were no significant differences in ISH (P = .72), DR (P = .85), VAS of back pain (P = .55), VAS of leg pain (P = .83) and ODI (P = .68) were found between 2 groups. After 12-month treatment, there were no significant differences in ISH (P = .26), VAS of back pain (P = .09) and VAS of leg pain (P = .96) between two groups. Significant differences of DR (P = .02), ODI (P = .03) and adverse events (P = .00) were found between 2 groups.

CONCLUSIONS

The results of this prospectively study showed that the ball-point slide-type interbody distractor in the posterior reduction and internal fixation produced good outcomes after 12-month treatment. More high quality randomized controlled trials and cases should still be needed to warrant the results of this study.

Current Evidence Regarding the Diagnostic Methods for Pediatric Lumbar Spondylolisthesis: A Report From the Scoliosis Research Society Evidence Based Medicine Committee

STUDY DESIGN

Structured literature review.

OBJECTIVES

The Scoliosis Research Society (SRS) requested an assessment of the current state of peer-reviewed evidence regarding pediatric lumbar spondylolisthesis with the goal of identifying what is known and what gaps remain in further understanding the diagnostic methods for pediatric spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Spondylolisthesis in the lumbar spine is common among children and adolescents and no formal synthesis of the published literature regarding diagnostic methods has been previously performed.

METHODS

A comprehensive literature search was performed. Abstracts were reviewed and data from included studies were analyzed by the committee. From 6600 initial citations with abstract, 663 articles underwent full-text review. The best available evidence for the clinical questions regarding diagnostic methods was provided by 26 included studies. Six of the studies were graded as Level III (retrospective comparative), and represent the current best available evidence whereas 20 of the studies were graded as Level IV (retrospective case series) evidence. No Level V (expert opinion) studies were included in the final list. None of the studies were graded as Level I or Level II.

RESULTS

Plain radiography is the workhorse imaging modality for diagnosing spondylolisthesis. No association between radiologic grade of spondylolisthesis and clinical presentation were noted; however, grade III and IV slips more often required surgery, and increasing slip angles were associated with worse baseline outcome scores. There is Level III evidence that the Meyerding grade appears to be more accurate for measuring slip percentage whereas the Lonstein Slip angle and Dubousset Lumbosacral Kyphosis angles are the best for measuring lumbosacral kyphosis in spondylolisthesis. In addition, higher sacral table index, pelvic incidence, sacral slope, and lower sacral table angle were associated with spondylolisthesis. True incidence could not be determined by the current literature available. However, studies in adolescent athletes demonstrated an incidence of 6% to 7% across studies.

CONCLUSIONS

The current "best available" evidence to guide the diagnosis and characterization of pediatric spondylolisthesis is presented. Future studies are needed to provide more high-quality evidence to answer these clinically relevant questions.

LEVEL OF EVIDENCE

Level III, review of Level III studies.

L5 incidence: an important parameter for spinopelvic balance evaluation in high-grade spondylolisthesis

BACKGROUND

In high-grade spondylolisthesis (HGSPL), the pelvic incidence (PI) is not a reliable measurement because of doming of the sacrum. Measurement of L5 incidence (L5I) was described as a tool to measure pelvic morphology in HGSPL and for surgical follow-up.

OBJECTIVE

We aimed to evaluate L5I in HGSPL and its relationship to other spinopelvic parameters.

STUDY DESIGN

A retrospective study of a cohort of 184 patients with HGSPL was carried out.

METHODS

Whole spine radiographs were analyzed for PI, pelvic tilt (PT), sacral slope, lumbar lordosis (LL), L5I, L5 tilt (L5T), L5 slope, lumbosacral kyphosis, and slip percentage. Statistical analysis and correlation were made (Pearson correlation test; p<.05). In accordance to Cohen, statically significant correlation were considered strong if R>0.5, moderate if 0.3<R<0.5, and small if R<0.3.

RESULTS

A total of 184 cases were analyzed, with a female-to-male ratio of 2.35 and a mean age of 20.1 years. Sacral doming was present in 73% of the cases. Mean L5I incidence was 65.2° and strongly correlated to other sagittal parameters, especially PT (R=0.7), LL (R=0.7), L5T (R=0.77), and L5 slope (R=0.83). There was less but still strong correlation to Dubousset lumbosacral kyphosis (Dub-LSK) angle (R=-0.63) and percentage of slippage (R=0.56). L5 tilt showed nearly perfect correlation to PT (R=0.95). Forty-four percent of the cases were balanced HGSPL, whereas 56% of the cases were unbalanced HGSPL. L5 incidence was found to be a good predictor of local imbalance with a cutoff of L5I=61.

CONCLUSION

This paper describes L5I, which is a positional parameter in HGSPL. L5 incidence is a simple and reliable measure in the preoperative setting in HGSPL. Its correlation with spinal sagittal parameters (especially PT and LL) is strong and was found to be better than Dub-LSK. There is also a good correlation between L5I and HGSPL pelvic parameters (slip percentage and lumbosacral kyphosis). We recommend its use for evaluation of surgical correction and recommend the value of 60° as cutoff value to define spinopelvic balance in HGSPL.

Radiographic analysis of spondylolisthesis and sagittal spinopelvic deformity

Traditional radiographic analysis of spondylolisthesis focuses on the regional sagittal deformity at the lumbosacral junction. Pelvic morphology has also been cited as an important factor that contributes to the development of high-grade spondylolisthesis. However, the importance of global sagittal balance of the spine and pelvis in patients with spondylolisthesis has been emphasized recently. Patients with this condition can develop abnormal sagittal spinopelvic balance; restoration of sagittal spinal alignment can improve their health-related quality of life. Reduction has been used to restore alignment, but its role in the management of high-grade spondylolisthesis is controversial. None of the current classification systems take sagittal sacropelvic and spinopelvic balance into account. Improved understanding of the relationship between the spine and pelvis has led to the development of a new classification system that incorporates analysis of spinopelvic balance in the radiographic assessment. This new system may aid surgeons in identifying patients who would benefit from a partial reduction procedure.