Tabori-Jensen Steffan, Frølich Christina, Hansen Torben B, Bøvling Søren, Homilius Morten, Stilling Maiken
1 Department of Orthopaedics, University Clinic for Hand, Hip and Knee Surgery, Hospital Unit West, Holstebro - Denmark.
2 Department of Clinical Medicine, Aarhus University, Aarhus - Denmark.
Hip Int. 2018 Mar;28(2):125-132. doi: 10.1177/1120700018768615.
Dual mobility (DM) total hip arthroplasty (THA) may reduce dislocation risk, but might increase the risk of high polyethylene (PE) wear due to double wearing surfaces.
127 patients (97 female) with 129 hips operated with THA after displaced femoral neck fracture FNF between 2005 and 2011, were seen for a cross-sectional clinical follow-up. Acetabular components were Saturne® DM cups with 28mm chrome-cobalt heads in UHMWPE. Cementless cups (n = 73) were hydroxyapatite coated. Radiographs were obtained for analysis of cup placement, 2D polyethylene wear and wear-rate (PolyWare 3D), and further radiological evaluation. Activity measurements included Timed Up and Go test (TUG) and walking distance from Harris Hip Score (HHS).
At a mean follow-up of 2.83 (1.0-7.7) years the mean wear was 0.82 mm (range 0.17-4.51, SD 0.50), and the wear-rate was 0.37 mm (range 0.06-1.90, SD 0.29). Wear-rate of 0.43 mm/year (SD 0.30) in cementless cups was higher (p = 0.004) than 0.30 mm/year (SD 0.27) in cemented cups. Mean age at time of surgery was 75.1 years (range 30-95). There was no correlation between age at time of surgery and wear (p = 0.56). There was no correlation between cup inclination and wear-rate (p = 0.35). TUG was mean 13.4 seconds (range 4.5-30.1) and correlated with wear rate (p = 0.03).
At short term follow-up, the mean wear-rate in old and low demand patients was high, correlated to activity, and was above the generally accepted osteolysis threshold (0.1 mm/yr.). Cementless HA-coated cups had higher wear-rate than cemented cups.
双动（DM）全髋关节置换术（THA）可能会降低脱位风险，但由于存在两个磨损表面，可能会增加高交联聚乙烯（PE）磨损的风险。
对2005年至2011年间因股骨颈骨折（FNF）移位后接受THA手术的127例患者（97例女性）的129个髋关节进行横断面临床随访。髋臼组件为带有28毫米铬钴股骨头的Saturne® DM髋臼杯，内衬超高分子量聚乙烯（UHMWPE）。非骨水泥杯（n = 73）采用羟基磷灰石涂层。获取X线片以分析髋臼杯位置、二维聚乙烯磨损及磨损率（PolyWare 3D），并进行进一步的影像学评估。活动量测量包括计时起立行走测试（TUG）以及根据Harris髋关节评分（HHS）得出的行走距离。
平均随访2.83（1.0 - 7.7）年，平均磨损为0.82毫米（范围0.17 - 4.51，标准差0.50），磨损率为0.37毫米（范围0.06 - 1.90，标准差0.29）。非骨水泥杯的磨损率为0.43毫米/年（标准差0.30），高于骨水泥杯的0.30毫米/年（标准差0.27）（p = 0.004）。手术时的平均年龄为75.1岁（范围30 - 95岁）。手术时的年龄与磨损之间无相关性（p = 0.56）。髋臼杯倾斜度与磨损率之间无相关性（p = 0.35）。TUG平均为13.4秒（范围4.5 - 30.1），且与磨损率相关（p = 0.03）。
在短期随访中，老年及活动需求低的患者平均磨损率较高，与活动量相关，且高于普遍认可的骨溶解阈值（0.1毫米/年）。非骨水泥羟基磷灰石涂层杯的磨损率高于骨水泥杯。
