World Neurosurg
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Recently, calcium phosphate (CaP) cement, instead of polymethylmethacrylate, has been injected into the compressed vertebral body. Calcium phosphate may have the potential for ectopic or heterotopic ossification and, thus, injected CaP cement can induce unwanted heterotopic ossifications in the human body. ⋯ We suggest that heterotopic ossification may be complications of vertebroplasty with CaP. Therefore, we strongly recommended that the patients who undergo a vertebroplasty with CaP need strict observation.
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Laser-assisted spinal endoscopy (LASE) kit has been used for percutaneous intradiscal decompression to evaporate and shrink the posterior and central nucleus for improvement of leg and radicular pain due to contained disc herniation. Percutaneous endoscopic laser annuloplasty (PELA), a new minimally invasive technique, uses LASE to directly coagulate the inflamed disc granulation tissue associated with annular tears. The small diameter of the endoscope including Ho:YAG laser, irrigation, and light, plus the extreme posterolateral approach into the posterior annulus, enables one to minimize damage to normal nuclear tissue. The authors sought to demonstrate the safety and efficacy of PELA for controlling discogenic low back pain (DLBP) due to abnormal disc tissues, new vessels, and nerves in the central torn posterior annulus. ⋯ Percutaneous endoscopic laser annuloplasty using the Ho:YAG laser provides favorable outcomes for carefully selected groups of patients with DLBP.
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Many Virtual Environments require walking interfaces to explore virtual worlds much larger than available real-world tracked space. We present a model for generating virtual locomotion speeds from Walking-In-Place (WIP) inputs based on walking biomechanics. ⋯ We compared resulting speeds from Real Walking, GUD WIP, and LLCM-WIP via user study: The average output speeds for Real Walking and GUD WIP respond consistently with changing step frequency - LLCM-WIP is far less consistent. GUD WIP produces output speeds that are more locally consistent (smooth) and step-frequency-to-walk-speed consistent than LLCM-WIP.