Background:The presence of a thoracolumbar transitional vertebra (TLTV) and/or lumbosacral transitional vertebra (LSTV) may cause wrong-site surgery and problems while measuring spinopelvic parameters, including pelvic incidence and lumbar lordosis. The Castellvi classification of LSTV addresses coronal images but not sagittal or axial images. Therefore, it is unclear how LSTV differs from the normal lumbosacral anatomy. We aimed to investigate the lumbosacral anatomy and vertebral numbering in patients with TLTV and/or LSTV. We performed computed tomography (CT) to identify TLTV, to number presacral vertebrae accurately, and to analyze morphological differences in each LSTV type.Methods:The medical records of 880 patients who underwent spinopelvic fixation between July 2014 and March 2020 were evaluated for TLTV and LSTV. Castellvi LSTVs (above the promontory on the arcuate line of the ilium) and our newly proposed LSTV (“S6 LSTV,” with 6 sacral vertebrae and 5 foramina below the promontory) were analyzed. The anatomical location of the lowest thoracic vertebra was defined, and TLTV with dysplastic ribs was identified. Each LSTV type was examined for its morphological features on sagittal and axial CT images.Results:LSTV was observed in 111 (12.6%) of 880 patients. Castellvi type-III LSTV was the most common (42 [37.8%] of 111), followed by S6 LSTV (37 [33.3%] of 111). TLTV was associated with LSTV (87 [78.4%] of 111) and was commonly identified at T13 (59 [67.8%] of 87). On sagittal CT images, the lumbosacral transitional anatomy of Castellvi LSTVs resembled that of normal L5-S1, and the lumbosacral transitional anatomy of S6 LSTV resembled that of normal S1-S2. When comparing the S1 upper segments on axial CT images, most Castellvi LSTVs exhibited S2-like appearances and most S6 LSTVs exhibited L5-like appearances.Conclusions:Although LSTV possesses L5 and S1 features, Castellvi LSTVs have more L5 elements than S1 elements. The converse is true for S6 LSTV. At least for the Castellvi type-IIIb LSTV, the vertebra below the Castellvi type-IIIb LSTV should be recognized as S1, but clinically it is better to recognize it as S2. Overlooking TLTV may cause problems in vertebral numbering due to coexisting LSTV.Clinical Relevance:Three-dimensional CT images are suitable for detecting transitional vertebrae. This study reveals their morphological features on axial CT images and their lumbosacral anatomy on sagittal CT images.

Introduction Mutilating-type rheumatoid arthritis, the most aggressive type of rheumatoid arthritis, is frequently associated with destructive cervical involvement, both at the high-cervical and subaxial levels, causing significant neurological deficit, and their natural course of the disease and the survival are discouraging. For such cases, we have been actively performing occipito-thoracic fusion since 1991. Although medical treatment for rheumatoid patients has represented a marked improvement, it could not treat all of these patients because of several reasons. Therefore, it is still important to evaluate the past treatment results. Methods We investigated the neurological improvement and prognosis in 51 mutilating-type rheumatoid arthritis patients who underwent occipito-thoracic fusion between 1991 and 2010. The neurological status was evaluated using modified Ranawat classification; class IIIB was subdivided into IIIBa (able to sit upright) and IIIBb (bedridden). Results The preoperative neurologic status was IIIBa in 19 patients and IIIBb in 17 patients. 15 of the 19 patients with class IIIBa improved to being able to walk (79 %), whereas only 3 of the 17 patients with class IIIBb improved to being able to walk (18 %) after surgery. Of the 51 patients, 28 died during follow-up; the mean age at death was 67.2 years. The postoperative 5-and 10-year survival rates were 60.3 and 26.4 %, respectively. Conclusion The neurological improvement and prognosis after surgery was poorer in class IIIBb patients than in the other patient groups. Occipito-thoracic fusion can improve the neurological symptoms and prognosis. However, early surgical intervention is recommended, before a patient becomes bedridden (class IIIBb).

Study DesignCase report.ObjectiveThe authors present the case of a 14-year-old boy with Rubinstein-Taybi syndrome (RSTS) presenting scoliosis.Summary of Background DataThere have been no reports on surgery for RSTS presenting scoliosis.MethodsThe patient was referred to our hospital for evaluation of a progressive spinal curvature. A standing anteroposterior spine radiograph at presentation to our hospital revealed an 84-degree right thoracic curve from T6 to T12, along with a 63-degree left lumbar compensatory curve from T12 to L4. We planned a two-staged surgery and decided to fuse from T4 to L4. The first operation was front-back surgery because of the rigidity of the right thoracic curve. The second operation of lumbar anterior discectomy and fusion was arranged 9 months after the first surgery to prevent the crankshaft phenomenon due to his natural course of adolescent growth. To avoid respiratory complications, the patient was put on a respirator in the ICU for several days after both surgeries.ResultsFull-length spine radiographs after the first surgery revealed no instrumentation failure and showed that the right thoracic curve was corrected to 31 degrees and the left lumbar curve was corrected to 34 degrees. No postoperative complications occurred after both surgeries.ConclusionsWe succeeded in treating the patient without complications. Full-length spine standing radiographs at one year after the second operation demonstrated a stable bony arthrodesis with no loss of initial correction.

Study Design: A novel technique for S2-alar-iliac (S2AI) screw placement was analyzed. Objectives: Accurate confirmation of the S2AI screw trajectory with free-hand techniques is not simple, although some anatomical landmarks have been reported. To overcome the drawback, we aimed to introduce our technique for S2AI screw placement assisted with a guidewire using a new anatomical landmark. Methods: A total of 104 S2AI screws of 52 patients who underwent S2AI screw placement were investigated. Navigation software was used to simulate S2AI screw placement preoperatively. Screw placement was performed with the nonfluoroscopic free-hand technique. In this technique, a guidewire is inserted into the ilium from the extra-articular portion of the sacroiliac joint just lateral to the ideal screw entry point toward the tip of the greater trochanter and guides the screw trajectory. If the direction of the guidewire is satisfactory, all procedures of screw insertion are performed accordingly. The screw accuracy was assessed with computed tomography. Results: The modal size of the screw was 9.5 mm × 90 mm. The average horizontal angle was 42.0° (SD = 5.1°) on the right and 40.7° (SD = 4.7°) on the left. Of the 104 screws, 4 screws (3.9%) breached dorsally. No screw-related complication was observed. Conclusions: Because the guidewire can be inserted at an angle according to the individual morphology of the sacroiliac joint, it will be a reliable guide for the screw trajectory. This technique with a guidewire would help improve the accuracy of S2AI screw placement.

Background This paper intends to clarify clinical and anatomical features as well as pathological conditions of surgically treated adult patients with occipitalization of the atlas.