Department of Mechanical Engineering, Imperial College London, South Kensington Campus, London, UK.
Department of Mechanical Engineering, Imperial College London, South Kensington Campus, London, UK; Department of Orthopaedic Surgery, Bicetre Hospital, Le Kremlin-Bicêtre, France.
J Shoulder Elbow Surg. 2020 May;29(5):1019-1029. doi: 10.1016/j.jse.2019.09.041. Epub 2020 Jan 13.
Hemiarthroplasty has clear advantages over alternative procedures and is used in 20% of all shoulder joint replacements. Because of cartilage wear, the clinical outcome of hemiarthroplasty is unreliable and controversial. This paper suggests that the optimal choice of prosthetic material may reduce cartilage degeneration and improve the reliability of the procedure. The specific objectives were to assess 3 materials and assess how the severity of arthritis might affect the choice of prosthetic material.
A CoCr alloy, an ALO ceramic, and a polycarbonate urethane polymer (PCU) were mechanically tested against 5 levels of human osteoarthritic cartilage (from intact to severely arthritic, n = 45). A high friction coefficient, a decrease in Young's modulus, an increase in permeability, a decrease in relaxation time, an increase in surface roughness, and a disrupted appearance of the cartilage after testing were used as measures of cartilage damage. The biomaterial that caused minimal cartilage damage was defined as superior.
The CoCr caused the most damage. This was followed by the ALO ceramic, whereas the PCU caused the least amount of damage. Although the degree of arthritis had an effect on the results, it did not change the trend that CoCr performed worst and PCU the best.
This study indicates that ceramic implants may be a better choice than metals, and the articulating surface should be as smooth as possible. Although our results indicate that the degree of arthritis should not affect the choice of prosthetic material, this suggestion needs to be further investigated.
半髋关节置换术相对于其他手术方法具有明显优势，在所有肩关节置换术中占比 20%。由于软骨磨损，半髋关节置换术的临床效果并不可靠，存在争议。本文提出，选择最佳的假体材料可能会减少软骨退变，提高手术的可靠性。具体目标是评估 3 种材料，并评估关节炎的严重程度可能如何影响假体材料的选择。
对 CoCr 合金、ALO 陶瓷和聚碳酸酯聚氨酯聚合物（PCU）这 3 种材料进行了机械测试，测试材料共接触了 5 个人体骨关节炎软骨样本（从完整到严重关节炎，n = 45）。高摩擦系数、杨氏模量降低、渗透率增加、弛豫时间缩短、表面粗糙度增加以及软骨测试后的外观破坏等，均被视为软骨损伤的衡量标准。造成软骨损伤最小的生物材料被定义为更优。
CoCr 造成的损伤最大。其次是 ALO 陶瓷，而 PCU 造成的损伤最小。尽管关节炎的严重程度对结果有影响，但并未改变 CoCr 表现最差、PCU 表现最好的趋势。
本研究表明，陶瓷植入物可能是优于金属的选择，且关节表面应尽可能光滑。虽然我们的研究结果表明关节炎的严重程度不应影响假体材料的选择，但这一建议仍需进一步研究。
