STUDY DESIGN: Anatomical study. PURPOSE: To evaluate the anatomy of intervertebral disc (IVD) area in the triangular working zone of the lumbar spine based on cadaveric measurements. OVERVIEW OF LITERATURE: The posterolateral percutaneous approach to the lumbar spine has been widely used as a minimally invasive spinal surgery. However, to our knowledge, the actual perspective of disc boundaries and areas through posterolateral endoscopic approach are not well defined. METHODS: Ninety-six measurements for areas and dimensions of IVD in Kambin's triangle on bilateral sides of L1–S1 in 5 fresh human cadavers were studied. RESULTS: The trapezoidal IVD area (mean±standard deviation) for true working space was 63.65±14.70 mm2 at L1–2, 70.79±21.88 mm2 at L2–3, 99.03±15.83 mm2 at L3–4, 116.22±20.93 mm2 at L4–5, and 92.18±23.63 mm2 at L5–S1. The average dimension of calculated largest ellipsoidal cannula that could be placed in IVD area was 5.83×11.02 mm at L1–2, 6.97×10.78 mm at L2–3, 9.30×10.67 mm at L3–4, 8.84×13.15 mm at L4–5, and 6.61×14.07 mm at L5–S1. CONCLUSIONS: The trapezoidal perspective of working zone of IVD in Kambin's triangle is important and limited. This should be taken into consideration when developing the tools and instruments for posterolateral endoscopic lumbar spine surgery.
Cadaver* ; Catheters ; Humans ; Intervertebral Disc* ; Spine

PURPOSE: The authors investigated the effect of lumbar facet tropism (FT) on intervertebral disc degeneration (DD), facet joint degeneration (FJD), and segmental translational motion. MATERIALS AND METHODS: Using kinetic MRI (KMRI), lumbar FT, which was defined as a difference in symmetry of more than 7degrees between the orientations of the facet joints, was investigated in 900 functional spinal units (300 subjects) in flexion, neutral, and extension postures. Each segment at L3-L4, L4-L5, and L5-S1 was assessed based on the extent of DD (grade I-V) and FJD (grade 1-4). According to the presence of FT, they were classified into two groups; one with FT and one with facet symmetry. For each group, demographics, DD, FJD and translational segmental motion were compared. RESULTS: The incidence of FT was 34.5% at L3-L4, 35.1% at L4-L5, and 35.2% at L5-S1. Age and gender did not show any significant relationship with FT. Additionally, no correlation was observed between DD and FT. FT, however, wasfound to be associated with a higher incidence of highly degenerated facet joints at L4-L5 when compared to patients without FT (p < 0.01). Finally, FT was not observed to have any effects upon translational segmental motion. CONCLUSION: No significant correlation was observed between lumbar FT and DD or translational segmental motion. However, FT was shown to be associated significantly with the presence of high grades of FJD at L4-L5. This suggests that at active sites of segmental motion, FT may predispose to the development of facet joint degeneration.
Adolescent ; Adult ; Age Factors ; Aged ; Aged, 80 and over ; Female ; Humans ; Intervertebral Disk Displacement/*etiology/pathology ; Joint Diseases/*complications/pathology ; Lumbar Vertebrae/*pathology ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Sex Factors ; Zygapophyseal Joint/*pathology/physiopathology

STUDY DESIGN: A prospective cohort. PURPOSE: To report the short and long term outcomes of fluoroscopically guided lumbar transforaminal epidural steroid injection (TFESI) in degenerative lumbar spondylolisthesis (DLS) patients. OVERVIEW OF LITERATURE: TFESI has been widely used for the treatment of lumbosacral radicular pains. However, to our knowledge, there has been no study which has evaluated the outcomes of TFESI in patients with DLS. METHODS: The DLS patients received fluoroscopically guided lumbar TFESI with 80 mg of methylprednisolone and 2 mL of 1% lidocaine hydrochloride. Patients were evaluated by an independent observer before the initial injection, at 2 weeks, at 6 weeks, at 3 months, and at 12 months after the injections. Visual analog scale (VAS), Roland 5-point pain scale, standing tolerance, walking tolerance, and patient satisfaction scale were evaluated for outcomes. RESULTS: Thirty three DLS patients treated with TFESI, who were completely followed up, were included in this study. The average number of injections per patient was 1.9 (range from 1 to 3 injections per patient). Significant improvements in VAS and Roland 5-point pain scale were observed over the follow up period from 2 weeks to 12 months. However, the standing and walking tolerance were not significantly improved after 2 weeks. At 2 weeks, the patient satisfaction scale was highest, although, these outcomes declined with time. The DLS patients with one level of spinal stenosis showed significantly better outcome than the DLS patients with two levels of spinal stenosis. Five patients (13%) underwent surgical treatment during the 3 to 12 months follow up. CONCLUSIONS: TFESI provides short term improvements in VAS and Roland 5-point pain scale, standing tolerance, walking tolerance and patient satisfaction scale in DLS patients. In the long term, it improves VAS but limits the improvements in Roland 5-point pain scale, standing tolerance, walking tolerance and patient satisfaction scale.
Cohort Studies ; Follow-Up Studies ; Humans ; Injections, Epidural ; Lidocaine ; Methylprednisolone ; Patient Satisfaction ; Prospective Studies ; Spinal Stenosis ; Spondylolisthesis* ; Visual Analog Scale ; Walking

Background: Many scoring systems that predict overall patient survival are based on clinical parameters and primary tumor type. To date, no consensus exists regarding which scoring system has the greatest predictive survival accuracy, especially when applied to specific primary tumors. Additionally, such scores usually fail to include modern treatment modalities, which influence patient survival. This study aimed to evaluate both the overall predictive accuracy of such scoring systems and the predictive accuracy based on the primary tumor. Methods: A retrospective review on spinal metastasis patients who were aged more than 18 years and underwent surgical treatment was conducted between October 2008 and August 2018. Patients were scored based on data before the time of surgery. A survival probability was calculated for each patient using the given scoring systems. The predictive ability of each scoring system was assessed using receiver operating characteristic analysis at postoperative time points; area under the curve was then calculated to quantify predictive accuracy. Results: A total of 186 patients were included in this analysis: 101 (54.3%) were men and the mean age was 57.1 years. Primary tumors were lung in 37 (20%), breast in 26 (14%), prostate in 20 (10.8%), hematologic malignancy in 18 (9.7%), thyroid in 10 (5.4%), gastrointestinal tumor in 25 (13.4%), and others in 40 (21.5%). The primary tumor was unidentified in 10 patients (5.3%). The overall survival was 201 days. For survival prediction, the Skeletal Oncology Research Group (SORG) nomogram showed the highest performance when compared to other prognosis scores in all tumor metastasis but a lower performance to predict survival with lung cancer. The revised Katagiri score demonstrated acceptable performance to predict death for breast cancer metastasis. The Tomita and revised Tokuhashi scores revealed acceptable performance in lung cancer metastasis. The New England Spinal Metastasis Score showed acceptable performance for predicting death in prostate cancer metastasis. SORG nomogram demonstrated acceptable performance for predicting death in hematologic malignancy metastasis at all time points. Conclusions The results of this study demonstrated inconsistent predictive performance among the prediction models for the specific primary tumor types. The SORG nomogram revealed the highest predictive performance when compared to previous survival prediction models.