Portet Adrien, Besnard Marion, Ratsimbazafy Carole, Berhouet Julien, Samargandi Ramy, Le Nail Louis-Romée
Service de Chirurgie Orthopédique, Hôpital Trousseau, CHRU de Tours, Avenue de la République, Chambray-lès-Tours, Tours Cedex 9, 37044, France.
Centre Hospitalier Intercommunal Amboise-Château-Renault, Hôpital Robert-Debré, rue des Ursulines, BP 329, 37403 Amboise Cedex, France.
Orthop Traumatol Surg Res. 2024 Sep 6:103988. doi: 10.1016/j.otsr.2024.103988.
For over 10 years, the RM Pressfit cup™ has been used in our department. This is a one-piece, elastic, cementless implant designed with standard polyethylene (PE), covered with a thin coating of titanium particles. To date, there is no French study evaluating this cup after more than 10 years. Therefore, we conducted a retrospective study in order to: (1) evaluate the survival of the implant with a minimum follow-up of 10 years, (2) evaluate the functional scores at the last follow-up, (3) measure the wear of the PE, (4) identify radiological loosening, (5) search for risk factors for cup removal, (6) identify complications that required management in the operating theatre.
The working hypothesis was that the survival of this implant was greater than 95% at 10 years' follow-up, in accordance with the criteria of the National Institute for Health and Care Excellence (NICE).
This was a retrospective monocentric study, including adult patients who underwent total hip arthroplasty (THA) with an RM Pressfit cup™ (28 mm friction size) for coxarthrosis (primary or secondary) or femoral head osteonecrosis. Exclusion criteria were a follow-up period of less than 10 years, the placement of an RM Pressfit cup™ as a secondary intention for a THA (n = 5) or following a trochanteric fracture (n = 1). In total, 163 patients (182 hips) with a median age (Q1-Q3) of 63 (56-68) years, and a sex ratio (M/F) of 1.7 were included. Functional scores were evaluated using the Harris and Oxford scores. Radiographs were analyzed in the immediate postoperative period and at the last follow-up.
The median follow-up was 10.5 (10-11.5) years. Of the 182 included hips, 7 cups were removed, corresponding to a 10-year survival rate of 96.1% (95% CI [93.3; 96.9]). The median Harris and Oxford scores at 10.5 years were 95 (90-98) and 19 (17-23) points, respectively. The median PE wear rate was 0.058 (0.039-0.087) mm/year. Univariate analysis showed that male gender was associated with PE wear (OR = 3.6; 95% CI [1.3; 12.9] [p = 0.012]). Ten cups (6%) showed radiological instability with migration greater than 3 mm and/or variation in inclination greater than 8 °, and only 9 hips (6%) showed bone resorption. No preoperative or perioperative factors analyzed were associated with cup removal. Dislocation accounted for 71% (n = 5) of the causes of cup removal. Additionally, 6 hips experienced at least one dislocation episode requiring reduction by external maneuvers in the operating room, bringing the overall dislocation rate in the series to 6% (n = 11). Increased cup inclination was the only risk factor for prosthetic dislocation (OR = 1.2; 95% CI [1.09; 1.4] [p = 0.0003]). Overall complications requiring surgical intervention included 15 (8.3%) implanted cups (7 removed cups, 6 dislocation episodes requiring reduction by external maneuvers in the operating room, and 2 hips reoperated for washing and changing of mobile components due to early infection).
The RM Pressfit cup™ gives good long-term clinical and radiological results with an overall survival of 96.1% and a low complication rate over 10 years. Over the last 2 years the RM Vitamys™ cup has been introduced allowing the use of 32 mm femoral head diameter for size 48 cups, to reduce the risk of dislocation.
IV; retrospective cohort.
十多年来，RM Pressfit杯™一直在我们科室使用。这是一种一体式弹性非骨水泥植入物，采用标准聚乙烯（PE）设计，表面覆盖一层薄钛颗粒涂层。迄今为止，法国尚无超过10年的关于该杯状植入物的研究。因此，我们进行了一项回顾性研究，目的是：（1）评估植入物在至少10年随访期后的生存率；（2）评估最后一次随访时的功能评分；（3）测量PE的磨损情况；（4）识别放射学松动；（5）寻找杯状植入物取出的危险因素；（6）识别需要在手术室处理的并发症。
工作假设是，根据英国国家卫生与临床优化研究所（NICE）的标准，该植入物在10年随访时的生存率大于95%。
这是一项回顾性单中心研究，纳入因髋关节炎（原发性或继发性）或股骨头坏死接受全髋关节置换术（THA）并使用RM Pressfit杯™（28毫米摩擦尺寸）的成年患者。排除标准为随访期少于10年、作为THA的二期手术植入RM Pressfit杯™（n = 5）或在转子间骨折后植入（n = 1）。总共纳入163例患者（182髋），中位年龄（Q1 - Q3）为63（56 - 68）岁，性别比（男/女）为1.7。使用Harris和Oxford评分评估功能评分。在术后即刻和最后一次随访时分析X线片。
中位随访时间为10.5（10 - 11.5）年。在182例纳入的髋部中，7个杯状植入物被取出，10年生存率为96.1%（95% CI [93.3; 96.9]）。10.5年时Harris和Oxford评分的中位数分别为95（90 - 98）分和19（17 - 23）分。PE磨损率的中位数为0.058（0.039 - 0.087）毫米/年。单因素分析显示男性与PE磨损相关（OR = 3.6；95% CI [1.3; 12.9] [p = 0.012]）。10个杯状植入物（6%）显示放射学不稳定，移位大于3毫米和/或倾斜度变化大于8°，只有9髋（6%）显示骨吸收。分析的术前或围手术期因素均与杯状植入物取出无关。脱位占杯状植入物取出原因的71%（n = 5）。此外，6髋经历至少一次脱位事件，需要在手术室通过外部手法复位，使该系列中的总体脱位率达到6%（n = 11）。杯状植入物倾斜度增加是假体脱位的唯一危险因素（OR = 1.2；95% CI [1.09; 1.4] [p = 0.0003]）。需要手术干预的总体并发症包括15个（8.3%）植入的杯状植入物（7个取出的杯状植入物、6次需要在手术室通过外部手法复位的脱位事件以及2髋因早期感染进行冲洗和更换活动部件的再次手术）。
RM Pressfit杯™在长期临床和放射学方面取得了良好的结果，10年总体生存率为96.1%，并发症发生率低。在过去两年中，引入了RM Vitamys™杯，对于48号杯状植入物可使用32毫米股骨头直径，以降低脱位风险。
IV；回顾性队列研究。
