Background:

Questions remain about whether circumferential labral reconstruction (CLR) using an iliotibial band (ITB) allograft can effectively restore the labral suction seal of the hip.

Hypotheses:

(1) CLR with an ITB allograft >6.5 mm would restore distractive stability force to that of the intact labrum. (2) CLR with an ITB allograft >6.5 mm would achieve significantly superior distractive stability force compared with CLR with an ITB allograft <6.5 mm.

Study Design:

Controlled laboratory study.

Methods:

A total of 6 fresh-frozen pelves with attached femurs (n = 12 matched hemipelves) from male donors were procured and dissected free of all soft tissue, including the hip capsule but preserving the native labrum, transverse acetabular ligament, and ligamentum teres. Potted hemipelves were placed in a saline bath and securely fixed to the frame of a hydraulic testing system. A 500-N compressive load was applied, followed by femoral distraction at a rate of 5.0 mm/s until the suction seal ruptured. Force and femoral displacement were continually recorded. Force versus displacement curves were plotted, the maximum force was recorded, and the amount of femoral distraction to rupture the suction seal was determined. After intact testing, the labrum was excised, and specimens were retested using the same protocol. CLR was subsequently performed twice in a randomized fashion using (1) an ITB allograft with a width >6.5 mm (7.5-9.0 mm) and (2) an ITB allograft with a width <6.5 mm (4.5-6.0 mm). Specimens were retested after each CLR procedure. Force (in Newtons) and femoral distraction (in millimeters) required to rupture the suction seal were measured and compared between the 4 testing states (intact, deficient, CLR <6.5 mm, and CLR >6.5 mm) using repeated-measures analysis of variance.

Results:

On average, intact specimens required 148.4 ± 33.1 N of force to rupture the hip suction seal, which significantly decreased to 44.3 N in the deficient state (P < .001). CLR with ITB allografts <6.5 mm did not improve the maximum force (63 ± 62 N) from the deficient state (P = .42) and remained significantly lower than the intact state (P < .01). CLR with ITB allografts >6.5 mm recorded significantly greater force to rupture the suction seal (135.8 ± 44.6 N) compared with both the deficient and CLR <6.5 mm states (P < .01), with a mean force comparable with the intact labrum (P = .59). The amount of femoral distraction to rupture the suction seal demonstrated similar findings.

Conclusion:

In a cadaveric model, CLR using ITB allografts >6.5 mm restored the distractive force and distance to the suction seal rupture to values comparable with hips with an intact labrum. CLR using ITB allografts >6.5 mm outperformed CLR with ITB allografts <6.5 mm, demonstrated by a significantly higher force to rupture the suction seal and increased distraction before the rupture.

Clinical Relevance:

The results of this cadaveric investigation suggest that using wider labral allografts during CLR will provide the distractive force required to rupture the suction seal and immediate postoperative stability of the hip, although further studies are required to determine if these results translate to improved clinical outcomes.

中文翻译：

---

用于环盂唇重建的同种异体移植物宽度增加更好地恢复了髋关节的分散稳定性：尸体生物力学分析

背景：

关于使用髂胫束 (ITB) 同种异体移植物的环盂唇重建 (CLR) 是否能有效地恢复髋关节的盂唇吸引密封的问题仍然存在。

假设：

(1) ITB 同种异体移植 >6.5 mm 的 CLR 将分散稳定力恢复到完整盂唇的稳定力。(2) 与 ITB <6.5 mm 的 CLR 相比，ITB 同种异体移植物 >6.5 mm 的 CLR 将获得显着优越的分散稳定力。

学习规划：

受控实验室研究。

方法：

从男性捐赠者那里获得了总共 6 个带有股骨的新鲜冷冻骨盆（n = 12 个匹配的半骨），并从所有软组织中分离出来，包括髋关节囊，但保留了天然盂唇、髋臼横韧带和圆韧带。将盆栽的半马放入盐水浴中，并牢固地固定在液压测试系统的框架上。施加 500-N 的压缩载荷，然后以 5.0 mm/s 的速度牵引股骨，直到吸入密封件破裂。持续记录力和股骨位移。绘制力与位移曲线，记录最大力，并确定破裂吸入密封的股骨牵引量。在完整测试后，切除盂唇，并使用相同的方案重新测试样本。随后使用 (1) 宽度 >6.5 mm (7.5-9.0 mm) 的 ITB 同种异体移植物和 (2) 宽度 <6.5 mm (4.5-6.0 mm) 的 ITB 同种异体移植物以随机方式进行 CLR 两次。在每次 CLR 程序后重新测试样本。使用重复测量方差分析测量并比较 4 种测试状态（完整、缺陷、CLR <6.5 mm 和 CLR >6.5 mm）破裂吸入密封所需的力（以牛顿为单位）和股骨牵引（以毫米为单位） .

结果：

平均而言，完整的标本需要 148.4 ± 33.1 N 的力来破坏髋部吸入密封，在缺陷状态下显着降低至 44.3 N ( P < .001)。ITB 同种异体移植物 <6.5 mm 的 CLR 没有提高缺陷状态 ( P = .42) 的最大力 (63 ± 62 N)，并且仍然显着低于完整状态 ( P < .01)。与缺陷和 CLR <6.5 mm 状态相比，具有 ITB 同种异体移植物 >6.5 mm 的 CLR 记录到明显更大的破坏吸入密封的力 (135.8 ± 44.6 N) ( P < .01)，平均力与完整的盂唇相当（P = .59）。股骨牵张以破坏抽吸密封的量显示出类似的发现。

结论：

在尸体模型中，使用 ITB 同种异体移植物 >6.5 mm 的 CLR 将牵引力和与吸入密封破裂的距离恢复到与具有完整盂唇的臀部相当的值。使用 ITB 同种异体移植物 > 6.5 mm 的 CLR 优于使用 ITB 同种异体移植物 <6.5 mm 的 CLR，这表现为抽吸密封破裂的力显着增加，破裂前的分心增加。

临床相关性：

这项尸体研究的结果表明，在 CLR 期间使用更宽的盂唇同种异体移植物将提供破裂抽吸密封所需的牵引力和髋关节的术后即刻稳定性，尽管需要进一步的研究来确定这些结果是否转化为改善的临床结果。