Time to Set of Bone Cement with Warmed vs Room Temperature of Irrigation Water

Introduction Polymethyl methacrylate (PMMA), often referred to as bone cement, is an acrylic polymer widely utilized in orthopedics for both implant fixation and osseous defect filling. Bone cement is used in a variety of orthopedic procedures including arthroplasty, vertebroplasty and orthopedic trauma. PALACOS LV and Simplex HV are two of the many bone cement products used by orthopedics surgeons. Many clinically relevant factors have been shown to affect curing time of these products. A prolonged curing time can increase the duration of surgery, cost of surgery and complication risk. Methods In this study, 14 batches each of PALACOS and Simplex HV cement were mixed at different temperatures to compare the effect of heat on curing time. The cement, consisting of MMA powder and MMA stabilizer liquid, underwent mixing in a 70°F room. Prepackaged components were combined in a 10cm x 10cm container, stirred for 30 seconds, and formed into 2 spheres (2cm in diameter). The spheres were subjected to either a 106°F or 70°F saline bath, with the time to harden recorded. The curing process was considered complete when a second thermostat probe could not make an indentation. Results The average time to curing in the warm (106°F) and room temperature (70°F ) of Simplex HV groups were 337.08 ± 27.20 seconds and 725.77 ± 127.20, respectively. By placing the mixture in a warm 106°F saline bath, the time to stiffening in the warm bath was reduced by 388.69 seconds or about 6.49 minutes when compared to the room temperature bath (CI 320.64, 364.28; P<.001). The average post set temperatures for the warm group (98.96 ± 3.37°F) were higher than the room temperature group (70.72 ± 1.60°F). The average time to curing in warm (106°F) and room temperature (70°F ) groups for PALACOS were 325.71 ± 23.23 seconds and 813.57 ± 91.12, respectively. By placing the mixture in a warm 106°F saline bath, the time to stiffening in the warm bath was reduced by 487.86 seconds or about 8.13 minutes when compared to the room temperature bath (CI 312.30, 348.95l; P<.001). The average post set temperatures for the warm group (97.9 ± 1.95°F) were higher than the room temperature group (69.99 ± 1.40°F). Conclusion This study concludes that placing bone cement in a 106°F saline bath can reduce curing time by up to 8.13 minutes. By reducing the OR time, hospitals can improve efficiency, patient satisfaction and procedure cancellation rates, while shortening length of stay in the ICU, patient recovery, waiting times and cost.