背景:髋关节内疼痛是一项重大的临床挑战,与最近的研究暗示韧带的病变是潜在的贡献者。更何况,在接受关节保留干预的年轻患者中,圆韧带损伤尤其普遍。尽管一些研究已经调查了韧带圆的生物力学属性,报告发现的不一致和对尸体或动物模型的依赖引起了人们对将结果外推到临床实践的担忧。此外,缺乏专门针对受益于保留关节的手术干预的相关患者队列个体的韧带生物力学的研究.
目的:我们寻求(1)确定生物力学特性(极限失效载荷,抗拉强度,刚度,和弹性模量)接受手术髋关节脱位的患者的新鲜冷冻韧带,(2)确定与之相关的患者特异性因素。
方法:这是一项机构审查委员会批准的研究,研究了74例连续接受手术髋关节脱位以保留关节的患者(2021年8月至2022年9月)的术中收获的圆韧带。排除之前手术的患者后,创伤后畸形,缺血性坏死,滑脱的资本股骨干,和Perthes病,对31例患者的31条韧带进行分析。研究组的平均年龄为27±8岁,61%(19)的参与者是男性。手术的主要指征是股髋臼撞击。所有患者均进行了标准化的AP骨盆和轴向X光片以及CT扫描,以更好地对人群进行放射学描述并确定相关的放射学因素。将韧带在髋臼窝的起点和头窝的插入区域彻底横切,并储存在-20°C直至使用。通过定制夹具将样品安装到材料测试机上,该夹具使滑动和夹具处失效的可能性最小化。生成力-位移和应力-应变曲线。极限破坏载荷(N),抗拉强度(MPa),刚度(N/mm),测定弹性模量(MPa)。使用多元回归分析和亚组分析,我们测试了人口统计,退化,和射线照相因素作为潜在的相关因素。
结果:韧带的极限破坏载荷为126±92N,拉伸强度为1±1MPa。韧带显示出24±15N/mm的刚度和7±5MPa的弹性模量。在控制了年龄等潜在的混杂变量之后,窝/中央凹变性,和髋臼/股骨形态,我们发现,女性是一个独立的因素,更高的抗拉强度,刚度,和弹性模量。过度的股骨版本与较低的失效负荷(HR122[95%CI47至197])和刚度(HR15[95%CI2至27])独立相关。髋臼窝损伤与失效负荷降低相关(HR-93[95%CI-159至-27])。
结论:总体而言,圆韧带是一种相对较弱的韧带。性,变性,股骨过度是影响圆韧带强度的因素。与其他关节稳定韧带相比,圆韧带强度较低,这质疑它对髋关节稳定性的总体贡献。
结论:接受髋关节保留手术的年轻患者是圆韧带病变的高危人群。载荷到失效的基线值,抗拉强度,弹性模量,和僵硬是需要更好地了解这些病变在这个感兴趣的队列。
BACKGROUND: Intraarticular hip pain represents a substantial clinical challenge, with recent studies implicating lesions in the ligamentum teres as potential contributors. Even more so, damage to the ligamentum teres is particularly prevalent among young patients undergoing joint-preserving interventions. Although several studies have investigated the biomechanical attributes of the ligamentum teres, inconsistencies in reported findings and reliance on cadaveric or animal models have raised concerns regarding the extrapolation of results to clinical practice. Furthermore, there is a lack of research examining ligamentum teres biomechanics specifically within the relevant patient cohort-individuals who benefit from joint-preserving surgical interventions.
OBJECTIVE: We sought (1) to determine the biomechanical properties (ultimate load to failure, tensile strength, stiffness, and elastic modulus) of fresh-frozen ligaments from patients undergoing surgical hip dislocation, and (2) to identify patient-specific factors that are associated with them.
METHODS: This was an institutional review board-approved study on intraoperatively harvested ligamentum teres from 74 consecutive patients undergoing surgical hip dislocation for joint preservation (August 2021 to September 2022). After the exclusion of patients with previous surgery, posttraumatic deformities, avascular necrosis, slipped capital femoral epiphysis, and Perthes disease, 31 ligaments from 31 patients were analyzed. The mean age of the study group was 27 ± 8 years, and 61% (19) of participants were male. The main indication for surgery was femoroacetabular impingement. Standardized AP pelvic and axial radiographs and CT scans were performed in all patients for better radiological description of the population and to identify associated radiological factors. The ligament was thoroughly transected at its origin on the fossa acetabuli and at the insertion area on the fovea capitis and stored at -20°C until utilization. Specimens were mounted to a materials testing machine via custom clamps that minimized slippage and the likelihood of failure at the clamp. Force-displacement and stress-strain curves were generated. Ultimate failure load (N), tensile strength (MPa), stiffness (N/mm), and elastic modulus (MPa) were determined. Using a multivariate regression analysis and a subgroup analysis, we tested demographic, degenerative, and radiographic factors as potential associated factors.
RESULTS: The ligamentum teres demonstrated an ultimate load to failure of 126 ± 92 N, and the tensile strength was 1 ± 1 MPa. The ligaments exhibited a stiffness of 24 ± 15 N/mm and an elastic modulus of 7 ± 5 MPa. After controlling for potential confounding variables like age, fossa/fovea degeneration, and acetabular/femoral morphologies, we found that female sex was an independent factor for higher tensile strength, stiffness, and elastic modulus. Excessive femoral version was independently associated with lower load to failure (HR 122 [95% CI 47 to 197]) and stiffness (HR 15 [95% CI 2 to 27]). Damage to the acetabular fossa was associated with reduced load to failure (HR -93 [95% CI -159 to -27]).
CONCLUSIONS: Overall, the ligamentum teres is a relatively weak ligament. Sex, degeneration, and excessive femoral version are influencing factors on strength of the ligamentum teres. The ligamentum teres exhibits lower strength compared with other joint-stabilizing ligaments, which calls into question its overall contribution to hip stability.
CONCLUSIONS: Young patients undergoing hip-preserving surgery are the population at risk for ligamentum teres lesions. Baseline values for load to failure, tensile strength, elastic modulus, and stiffness are needed to better understand those lesions in this cohort of interest.