There are many occupational risk factors in operating room work. Polymethyl methacrylate (PMMA) , as a kind of common bone filling and repairing material, is widely used in the fixation of artificial joints, oral braces and orthopedic prosthesis. However, PMMA will release methyl methacrylate (MMA) monomer when it is implanted into human tissues and polymerized to harden, which is toxic to the body. This paper analyzes harmful factors in using PMMA bone cement, and then explores corresponding occupational protection knowledge, in order to reduce the occurrence of occupational hazards related to PMMA bone cement and enhance the self-protection ability of the operation room medical staff.
Bone Cements/adverse effects* ; Humans ; Operating Rooms ; Polymethyl Methacrylate/adverse effects*

Polymethl methacrylate (PMMA) screw reinforcement is frequently used in osteoporotic bone as well as in damaged pilot holes. However, PMMA use can be dangerous, since the amount of applied cement is uncontrolled. A 47-year-old male with traumatic cervical spondylolisthesis at C6-7 underwent anterior cervical plate fixation. During repeated drilling and tapping for false trajectory correction, a pilot hole was damaged. Although it was an unconventional method, PMMA augmentation was tried. However, PMMA was accidentally injected to the cervical spinal cord owing to lack of fluoroscopic guidance. The PMMA was surgically removed after corpectomy and durotomy. The patient had left side hemiparesis (Grade 2/5) immediately post operation. The patient improved spontaneously (Grade 4/5) except for 4th and 5th digit extension. Here, we report a rare complication of PMMA extrusion in the spinal cord during a damaged pilot hole injection, which has not previously been described.
Bone Cements/*adverse effects/therapeutic use ; Bone Screws ; Cervical Vertebrae/*surgery ; Humans ; Male ; Middle Aged ; Polymethyl Methacrylate/adverse effects/therapeutic use

OBJECTIVETo investigate the biomechanical effect of different volume, distribution and leakage to adjacent disc of bone cement on the adjacent vertebral body by three-dimensional osteoporosis finite element model of lumbar.

METHODSL(4)-L(5) motion segment data of the cadaver of an old man who had no abnormal findings on roentgenograms were obtained from computed tomography (CT) scans. Three-dimensional model of L(4)-L(5) was established with Mimics software, and finite element model of L(4)-L(5) functional spinal unit (FSU) was established by Ansys 7.0 software. The effect of different loading conditions and distribution of bone cement after vertebroplasty on the adjacent vertebral body was investigated.

RESULTSThis study presented a validated finite element model of L(4)-L(5) FSU with a simulated vertebroplasty augmentation to predict stresses and strains of adjacent untreated vertebral bodies. The findings from this FSU study suggested the endplate and disc stress of the adjacent vertebral body was not influenced by filling volume of bone cement but unipedicle injection and leakage to the disc of bone cement could concentrate the stress of adjacent endplate.

CONCLUSIONSAsymmetric distributions and leakage of cement into intervertebral disc can improve the stress of endplate in adjacent vertebral body. These results suggest that optimal biomechanical configuration should have symmetric placement and avoid leakage of cement in operation.

Bone Cements ; adverse effects ; pharmacology ; Finite Element Analysis ; Humans ; Imaging, Three-Dimensional ; Lumbar Vertebrae ; surgery ; Male ; Polymethyl Methacrylate ; adverse effects ; pharmacology ; Stress, Mechanical

OBJECTIVETo analyze the reasons of the complications,and the measures taken for the prevention and treatment by percutaneous vertebroplasty (PVP) for osteoporotic thoracolumbars vertebral compressive fractures.

METHODSFrom May 2004 to June 2008, 204 patients with 286 diseased vertebrae underwent PVP under the guidance of C-arm fluoroscopy, and 56 patients with complications included 18 males, 38 females, ranging in age from 58 to 93 years, with an average of 72 years. The condition of leakage of bone cement and complications was observed.

RESULTSThe complications related to the leakage of PMMA found in 60 vertebrae in 49 cases: vertebral canal in 5 cases, intervertebral foramina in 3 cases, soft tissue besides vertebrae in 20 cases,intervertebral discs in 15 cases, venous plexus besides vertebrae in 6 cases. The complications no related to the leakage of PMMA found in 7 cases: the nerve roots injuried in 3 cases; the pain of the patient worsened temporarily in 2 cases; the blood pressure of the patient descent temporarily in 2 cases.

CONCLUSIONThe main reasons of complications are no-integrated of the compressived vertebrae,unstandard skills of injecting,unsuitable opportunity and quantity of injecting PMMA, unsufficient monitoring of C-arm fluoroscopy, the toxicity of PMMA. The measures of prevention and treatment is strict indication, standard skills of injecting, sufficient monitoring of C-arm fluoroscopy, suitable opportunity and quantity of injecting PMMA, electrocardio-monitoring in operation.

Aged ; Aged, 80 and over ; Bone Cements ; adverse effects ; Female ; Fractures, Compression ; complications ; surgery ; Humans ; Lumbar Vertebrae ; surgery ; Male ; Middle Aged ; Polymethyl Methacrylate ; adverse effects ; Postoperative Complications ; prevention & control ; Spinal Fractures ; complications ; surgery ; Vertebroplasty

OBJECTIVETo evaluate the therapeutic effect of percutaneous vertebroplasty (PVP) guided by X-ray fluoroscopy in treating osteoporotic spinal compression fractures, hemangioma of vertebra and metastatic carcinoma of vertebra.

METHODSOne hundred and ninety patients with 275 diseased vertebra underwent PVP under the guidance of C-arm fluoroscopy (male 80, female 110, ranging in age from 53 to 91 years, with an average of 66 years). Bone marrow biopsy needle was inserted percutaneously via transpedicular way into the diseased vertebra. Polymethylmethacrylate (PMMA) was then injected into the diseased vertebra. Visual analogue scale (VAS), mobility and analgesic usage were evaluated pre-operation and 3 months after PVP.

RESULTSPVP was successful in 190 cases (275 vertebrae). VAS was tested by t test at 3 months after PVP (P < 0.05). Simultaneously, scale of patient's mobility and scale of analgesic usage was tested by rank sum test at 3 months after PVP (P < 0.05).

CONCLUSIONAs the mimimally invasive operation, PVP can alleviate pain in early time, avoid kinds of complications by shortening the patient's time in bed and have the characteristic of simply operative procedure and low expenses. It is an effective mini-invasive technique for osteoporotic spinal compression fractures, hemangioma of vertebra and metastatic carcinoma of vertebra.

Aged ; Aged, 80 and over ; Female ; Fluoroscopy ; Fractures, Compression ; surgery ; Humans ; Male ; Middle Aged ; Osteoporosis ; complications ; Polymethyl Methacrylate ; Postoperative Complications ; prevention & control ; Spinal Fractures ; surgery ; Spinal Neoplasms ; surgery ; Vertebroplasty ; adverse effects ; methods