Heat distribution of polymerisation temperature of bone cement on the spinal canal during vertebroplasty.

PURPOSE: In the last 15 years, vertebroplasty and kyphoplasty have become established operative procedures for treating osteoporotic vertebral-body fractures and vertebral bodies afflicted with metastases. These procedures are quickly performed with few personnel and material resources and have a low rate of complications. However, cases of neurological impairment are reported in the scientific literature. We analysed whether potentially harmful heat is radiated/conducted by the polymerisation temperature of polymethylmethacrylate (PMMA) bone cement in the spinal canal. METHODS: We performed vertebroplasty on 25 vertebral bodies and measured the temperature distribution during polymerisation of bone cement within the spinal canal using heat probes placed in the respective areas. The vertebral bodies were located in a circulating water bath at 37°C. RESULTS: During polymerisation of the bone cement, a temperature rise was measured. The peak temperature was reached after few minutes. Temperature curves differed; a maximum temperature of up to 43.16°C was detected for a few seconds only. CONCLUSION: When vertebroplasty is performed correctly, there is no temperature development that could eventually damage the spinal cord or spinal nerves.

Clinical and psychological phenomenology of pain in autoinflammatory diseases.

BACKGROUND: Pain is the clinical hallmark of patients in patients with autoinflammatory diseases (AID) caused by variants of the NLRP3-, MEFV- or TNFRSF1A gene. However, no systematical analysis of the clinical and psychological presentation of pain has been performed to date. METHODS: Twenty-one symptomatic patients with variants in the NLRP3-, MEFV- and TNFRSF1A gene and clinical signs suggestive of an AID were retrospectively included in this monocentric cross-sectional case-series study. Patients were examined and interviewed using the German pain questionnaire. The hospital anxiety and depression scale (HADS) was applied to screen patients for anxiety and depression. RESULTS: Twenty out of 21 AID patients (95%) reported pain at the time of examination. Mean current pain intensity in all AID patients comprised 3.6 ± 1.3 and mean maximum pain intensity was 7.0 ± 1.6 on a 11-point numeric ranging scale (NRS). In 15 patients (71%), pain was present for more than 60 months. Ten patients (48%) experienced recurrent attacks with asymptomatic intervals and 7 patients (33%) suffered from constant pain, while 4 patients (19%) experienced both. Nociceptive pain including musculoskeletal and visceral affection was the most prominent type of pain (n = 20; 95%). Pain symptoms were treated continuously with analgesic or co-analgesic drugs in 10 patients (48%). Five patients (24%) have been positively screened for concomitant depression or anxiety. CONCLUSIONS: Early and prompt diagnosis is necessary to provide multimodal pain treatment and to avoid the development of chronic pain in patients with AID.