Comparison of degenerative lumbar spondylolisthesis and isthmic lumbar spondylolisthesis: effect of pedicle screw placement on proximal facet invasion in surgical treatment

Background Pedicle screw invasion of the proximal articular process will cause local articular process degeneration and acceleration, which is an important factor affecting adjacent segment degeneration. Although lumbar spondylolisthesis is a risk factor for screw invasion of the proximal joint, there is no clear conclusion regarding the two different types of spondylolisthesis. Therefore, the purpose of this study was to explore the influence of pedicle screw placement on proximal facet invasion in the treatment of degenerative spondylolisthesis and isthmic spondylolisthesis. Methods In total, 468 cases of lumbar spondylolisthesis treated by decompression and fusion in our hospital from January 2017 to January 2020 were included in this retrospective study. Among them, 238 cases were degenerative spondylolisthesis (group A), and 230 cases were isthmic spondylolisthesis (group B). Sex, age, body mass index, bone mineral density, preoperative visual analog scale (VAS) and Oswestry Disability Index (ODI) scores, postoperative VAS and ODI scores at 1 month and 3 months, and angle of the proximal facet joint at the last follow-up were recorded and compared between the two groups. The degree of pedicle screw invasion of the proximal facet joint was graded and compared by the SEO grading method. Results There were no significant differences in sex, age, body mass index, bone mineral density, preoperative VAS and ODI scores, or proximal facet joint angle between the two groups (P > 0.05). There was no significant difference in VAS and ODI scores between the two groups at 1 month and 3 months after the operation (P > 0.05). The VAS score of group A at the last follow-up was 1 (1,2). The VAS score of group B at the last follow-up was 3 (1,3). The ODI score of group A at the last follow-up was 6(4,26). The ODI score of group B at the last follow-up was 15(8,36). The VAS and ODI scores of the two groups at the last follow-up were significantly different (P < 0.05). According to the SEO grading method, the invasion of the proximal articular process by pedicle screw placement in group A involved 320 cases in grade 0, 128 cases in grade I and 28 cases in grade II. In group B, there were 116 cases in grade 0, 248 cases in grade I and 96 cases in grade II, with a significant difference (P < 0.01). Conclusion In summary, a certain number of cases involving screws invading the proximal facet joint occurred in the two different types of lumbar spondylolisthesis, but the number in the isthmic spondylolisthesis group was significantly higher than that in the degenerative spondylolisthesis group, which caused more trauma to the proximal facet joint and significantly affected the patient prognosis.

A morphological characterization of the lumbar neural arch in females and males with degenerative spondylolisthesis

Background Although Degenerative Spondylolisthesis (DS) is a common osseous dysfunction, very few studies have examined the bony morphology of lumbar the neural arch in the population afflicted with DS. Therefore, this study aimed to characterize the neural arch (NA) morphology along the entire lumbar spine in individuals with degenerative spondylolisthesis (DS) and compare them to healthy controls. Methods One hundred CTs from a database of 500 lumbar CTs of spondylolisthesis were selected. We excluded vertebral fractures, non-L4-L5 slips, previous surgeries, vertebral spondyloarthropathies, and scoliosis. Scans were divided into a study group of 50 individuals with single-level DS (grades 1–2) at L4–5 (25 males and 25 females), and an age-sex matched control group of 50 individuals. Linear and angular measurements from all lumbar segments included: vertebral canals, intervertebral foramens, pedicles, and articular facets. Results Compared with the controls, all individuals with DS had greater pedicle dimensions in the lower lumbar segments (∆ = 1 mm–2.14 mm) and shorter intervertebral foramens in all the lumbar segments (∆range:1.85 mm–3.94 mm). In DS females, the lower lumbar facets were mostly wider (∆ = 1.73–2.86 mm) and more sagittally-oriented (∆10°) than the controls. Greater prevalence of grade-3 facet arthrosis was found only in the DS population (DS = 40–90%,controls = 16.7–66.7%). In DS males, degenerated facets were observed along the entire lumbar spine (L1-S1), whereas, in DS females, the facets were observed mainly in the lower lumbar segments (L4-S1). Individuals with DS have shorter intervertebral foramens and greater pedicle dimensions compared with controls. Conclusions Females with DS have wider articular facets, more sagittally-oriented facets, and excessively degenerated facets than the controls. This unique NA shape may further clarify DS’s pathophysiology and explain its greater prevalence in females compared to males.

Stable Low-Grade Degenerative Spondylolisthesis Does Not Compromise Clinical Outcome of Minimally Invasive Tubular Decompression in Patients with Spinal Stenosis

Background and Objectives: In recent literature, the routine addition of arthrodesis to decompression for lumbar spinal stenosis (LSS) with concomitant stable low-grade degenerative spondylolisthesis remains controversial. The purpose of this study is to compare the clinical outcome, complication and re-operation rates following minimally invasive (MIS) tubular decompression without arthrodesis in patients suffering from LSS with or without concomitant stable low-grade degenerative spondylolisthesis. Materials and Methods: This study is a retrospective review of prospectively collected data. Ninety-six consecutive patients who underwent elective MIS lumbar decompression with a mean follow-up of 27.5 months were included in the study. The spondylolisthesis (S) group comprised 53 patients who suffered from LSS with stable degenerative spondylolisthesis, and the control (N) group included 43 patients suffering from LSS without spondylolisthesis. Outcome measures included complications and revision surgery rates. Pre- and post-operative visual analog scale (VAS) for both back and leg pain was analyzed, and the Oswestry Disability Index (ODI) was used to evaluate functional outcome. Results: The two groups were comparable in most demographic and preoperative variables. VAS for back and leg pain improved significantly following surgery in both groups. Both groups showed significant improvement in their ODI scores, at one and two years postoperatively. The average length of hospital stay was significantly higher in patients with spondylolisthesis (p-value< 0.01). There was no significant difference between the groups in terms of post-operative complications rates or re-operation rates. Conclusions: Our results indicate that MIS tubular decompression may be an effective and safe procedure for patients suffering from LSS, with or without degenerative stable spondylolisthesis.

Posterior Lumbar Interbody Fusion with Preservation of Posterior Structures for Management of Lumbar Spondylolisthesis

Introduction: Successful posterior lumbar interbody fusion requires excessive removal of posterior spinal elements and distraction of neural structures. It also requires a large amount of bone graft. The authors have developed this technique to assess results of treatment of degenerative spondylolisthesis by posterior lumbar interbody fusion with preservation of posterior spinal elements and also to examine the safety and efficacy of the recapping T-saw laminoplasty technique for the management of degenerative lumbar spondylolisthesis using posterior lumbar interbody fusion by interbody cages with preservation of posterior elements. Methodology: Twenty-five patients with degenerative spondylolisthesis underwent recapping T-saw laminoplasty in the lumbar spine for posterior lumbar interbody fusion with interbody cage. The T-saw was used for the division of the posterior elements. After discectomy and insertion of cages, the excised lamina was replaced exactly in situ to their original anatomic position. Patients were followed neurologically and radiologically. Result: Only one lamina was excised and replaced again. Primary bone healing was obtained in all patients by four to six months post surgery. No complications such as postoperative spinal canal stenosis, facet arthrosis, or kyphosis were observed. Conclusion: This technique of posterior lumbar interbody fusion through recapping laminoplasty provide wide space for easier insertion of cages and allow anatomic reconstruction of the vertebral arch preserving its important mechanical roles.

Radiologic Cervical Parameters To Determine Ligamentous Injuries in Patients With Ankylosing Spondylitis – Are They Different?

Introduction: Cervical ligamentous injuries in patients with ankylosing spondylitis (AS) may be difficult to detect, even with the utilization of computed tomography (CT) scans. The purpose of this study was to investigate the influence AS has on various radiologic parameters used to detect traumatic and degenerative pathologies of the cervical spine. Methods: A matched, case-control retrospective analysis of patients with AS and controls without AS admitted at two level-1 trauma centers was performed. All patients were admitted via shock room and received a polytrauma CT. Study patients were included if they had no injury to the cervical spine. Twenty-four CT parameters of atlanto-occipital dislocation/ instability, traumatic and degenerative spondylolisthesis, basilar invagination, and prevertebral soft-tissue swelling were assessed. Study patients were matched by age and sex. Results: A total of 78 patients were included (AS group, n=39; control group, n=39). The evaluated cervical radiologic parameters were largely within normal limits and showed no significant clinical or morphologic differences between the two groups. Conclusion: In this analysis, CT measurements pertaining to various cervical pathologies were not different between patients with and without ankylosing spondylitis. Parameters to assess for atlanto-occipital dislocation/ instability, spondylolisthesis, or basilar invagination may reliably be used in patients with AS.