Central sensitization in osteoarthritic knee pain: A cross-sectional study.

Objectives: The aim of this study was to investigate central sensitization and associated factors in knee osteoarthritis (OA) patients and compare them with rheumatoid arthritis (RA) patients and healthy controls. Patients and methods: This cross-sectional study was conducted with 125 participants (7 males, 118 females; mean age: 57.2±8.2 years; range, 45 to 75 years) between January 2017 and December 2018. Sixty-two patients with symptomatic knee OA, 32 RA patients with knee pain, and 31 healthy controls constituted the participants. Central sensitization was investigated with the Central Sensitization Inventory (CSI) and pressure pain threshold (PPT) measurements. Pain, functional status, and psychosocial features were assessed with self-reported questionnaires. Results: The OA and RA groups had significantly lower PPT values at local, peripheral, and remote regions compared to the healthy controls. Pressure hyperalgesia was shown at the knee with a 43.5% prevalence, 27.4% at the leg, and 8.1% at the forearm of OA patients. Pressure hyperalgesia was present at the knee, leg, and forearm in 37.5%, 25%, and 9.4% of RA patients, respectively. Pressure pain threshold values, CSI scores, frequency of pressure hyperalgesia, and frequency of central sensitization according to the CSI were not statistically different between the OA and RA groups. Psychosocial features and structural damage were not correlated with PPT values in the OA group. Conclusion: The severity of chronic pain and functional status may be the clinical clues to recognizing patients with central sensitization since local joint damage does not play a direct role in the etiopathogenesis of central sensitization in OA patients and severe pain persisting in the chronic process is associated with central sensitization regardless of the pathogenesis.

Neuropathic arthropathy caused by Arnold-Chiari malformation with syringomyelia.

We report a case of neuropathic arthropathy caused by Arnold-Chiari malformation with syringomyelia, with details of the clinical and radiologic aspects. The patient had pain and stiffness in his left upper limb. MRI of the left shoulder revealed neuropathic arthropathy. Upon examination, his left elbow also had the characteristic findings for neuropathic arthropathy. Examination of the spinal cord by MRI confirmed Arnold-Chiari malformation associated with syringomyelia. Neuropathic arthropathy requires evaluation of the spinal cord to assess for occult causal lesions.

Osteoblastoma of the lumbar spine as a cause of chronic low back pain.

We report a case of osteoblastoma in the uncommon location of the L5 lumbar vertebra, detailing the clinical and radiologic aspects. Although the plain radiographs of the patient were normal, computed tomographic scans of the lumbar region confirmed the diagnosis of osteoblastoma or osteoid osteoma of the L5 vertebra. The patient was referred to the orthopedic department for operation. Histologic examination revealed osteoblastoma of the L5 vertebra. Following surgery, the patient's pain resolved completely. Although osteoblastoma is extremely rare in the spine, it should be included in the differential diagnosis as a cause of chronic back pain, especially in young males with painful scoliosis and/or radicular-type leg pain. The tumor is often not readily apparent on plain radiographs. Therefore, advanced radiological investigation is necessary to establish the correct diagnosis.