Soft tissue calcifications are common findings in patients with various diseases, such as malignant tumors, collagen diseases, trauma, and chronic kidney disease. The majority of these lesions are not clinically significant; however, they can cause specific disorders within a limited space, such as the spinal canal. Here, we report the case of a patient undergoing fusion surgery for lumbar canal stenosis due to degenerative spondylolisthesis and multiple intraspinal canal calcifications associated with psoriatic arthritis (PsA). A 55-year-old female patient presented with pain in the left leg and intermittent claudication for 1 month. One year ago, she was diagnosed with PsA and received outpatient treatment, including biological medication, at the Division of Rheumatology, Department of Internal Medicine of our institution. She was referred to our department, and radiological examination revealed lumbar canal stenosis caused by spondylolisthesis and multiple calcifications in the lumbar spinal canal. We performed posterior lumbar interbody fusion (PLIF) with percutaneous pedicle screw fixation concomitant with removal of the calcifications. The postoperative course was uneventful, and her neurological symptoms improved. Although several prior case reports have noted intraspinal canal calcifications due to collagen disease or chronic kidney disease, calcifications associated with PsA are rare. We discuss the diagnosis of PsA and its relationship with intraspinal canal calcifications by reviewing the previous relevant literature.

BACKGROUND: Degenerative spondylolisthesis (DS) is usually seen at L4-L5 level and less frequently at L5-S1 level. This is a rare case report of spondylolisthesis of S1 over S2 with lumbarization of S1. Lumbarization of S1 is seen in just 1-2% of the population and to have spondylolisthesis in this segment is even rarer. The purpose is to report a rare case of DS at S1-S2 level.
METHODS: This is a single case report of a 66-year-old gentleman who presented with complains of lower backache for 2 years and acute retention of urine to the emergency department. Detailed clinical and radiological evaluation of the spine was done which revealed lumbarization of S1 with spondylolisthesis at S1-S2 and facetal hypertrophy at L5, S1, and S2. He underwent decompression and stabilization at L5, S1, and S2 along with placement of autologous bone graft. The bladder symptoms disappeared after 3 weeks. At 1-year follow-up, patient\'s clinical symptoms were relieved, and he improved clinically.
CONCLUSIONS: To the best of our knowledge, this is probably the first case of DS of sacral vertebrae to be reported in English literature. The prevalence of complete lumbarization is around 1.8% and to get spondylolisthesis in this segment is even rarer, hence the lack of literature in this regard. Since this is the first of its kind of case, further case series or longitudinal studies of such cases may help understand better the pathomechanics related to spondylolisthesis at this level.

BACKGROUND: Essential thrombocythemia (ET) is a chronic myeloproliferative disorder characterized by a relatively benign clinical course that may be complicated by conflicting thrombosis and bleeding. Postoperative spinal epidural hematoma is an uncommon, but well-known, complication after spinal surgery.
OBJECTIVE: To describe a patient with ET who underwent surgery for lumbar spinal canal stenosis resulting in leg paraplegia and discuss the perioperative management for ET.
METHODS: Case report.
RESULTS: The patient with ET underwent laminoplasty and posterolateral fusion for degenerative spondylolisthesis and spinal stenosis at L4-L5. A hematoma was observed in the epidural cavity after surgery, and emergency surgical evacuation was performed. After revision surgery, bleeding from the wound continued for 2 months, despite transfusions of platelets and coagulation factors, and right unilateral leg paralysis developed.
CONCLUSIONS: This case presentation increases the awareness of this disorder to the spinal community and the need to establish guidelines for the perioperative management of patients who require surgery in similar settings.