Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
Department of Orthopaedic Surgery, Harvard Medical School, Boston, Massachusetts 02114, USA.
J Mater Chem B. 2024 Oct 17;12(40):10332-10345. doi: 10.1039/d4tb01050g.
Pain management after total joint arthroplasty is often addressed by systemic delivery of opioids. Local delivery of non-opioid analgesic drugs directly in the joint space from the UHMWPE component of the prosthesis would be highly beneficial to increase the efficacy of the drugs, decreasing the overall side effects and the risk of opioid addiction. It has been shown that effective concentrations of local analgesics can be achieved by eluting from analgesic-blended UHMWPE; however, this approach is limited by the decrease in mechanical properties resulting from the extent of phase separation of the blended drugs from the polymeric matrix. Here we hypothesized that mechanical properties could be maintained by incorporating analgesics into solid form UHMWPE by diffusion as an alternative method. Lidocaine or bupivacaine were diffused in solid form UHMWPE with or without radiation crosslinking. The loaded drug content, the spatial distribution of the drugs and their chemical stability after doping were characterized by FTIR and NMR spectroscopy, respectively. Drug release kinetics, tensile mechanical properties and wear rates were assessed. The results showed that diffusion doping could be used as a promising method to obtain a therapeutic implant material without compromising its mechanical and structural integrity.
全关节置换术后的疼痛管理通常通过全身给予阿片类药物来解决。直接将非阿片类镇痛药物从假体的超高分子量聚乙烯（UHMWPE）组件局部递送至关节腔内，将极大地提高药物的疗效，降低药物的整体副作用和阿片类药物成瘾的风险。已经表明，通过从镇痛混合 UHMWPE 中洗脱，可以达到有效的局部镇痛药浓度；然而，这种方法受到混合药物从聚合物基质中相分离程度导致的机械性能下降的限制。在这里，我们假设通过扩散将镇痛剂以固体形式掺入 UHMWPE 中作为替代方法可以保持机械性能。将利多卡因或布比卡因以固体形式扩散到 UHMWPE 中，无论是否进行辐射交联。通过傅里叶变换红外光谱（FTIR）和核磁共振（NMR）光谱分别对载药含量、药物的空间分布以及掺杂后的化学稳定性进行了表征。评估了药物释放动力学、拉伸力学性能和磨损率。结果表明，扩散掺杂可以用作一种有前途的方法来获得治疗性植入材料，而不会损害其机械和结构完整性。
