Background:There is concern that physiologic knee hyperextension may be associated with inferior outcomes after anterior cruciate ligament reconstruction (ACLR) using hamstring tendon (HT) autografts.Purpose:To assess whether there is an association between contralateral passive preoperative knee hyperextension (≤−5°) and postoperative anterior knee laxity, subjective knee function, or revision surgery after ACLR using HT autografts.Study Design:Cohort study; Level of evidence, 3.Methods:Patients without concomitant ligament injuries who underwent primary ACLR using an HT autograft at Capio Artro Clinic, Stockholm, Sweden, between January 1, 2005, and December 31, 2018, were identified. The cohort was dichotomized into the hyperextension group (≤−5°) and the no hyperextension group (>–5°) depending on preoperative contralateral passive knee extension degree. Anterior knee laxity (KT-1000 arthrometer; 134 N) was assessed preoperatively and at 6 months postoperatively. The Knee injury and Osteoarthritis Outcome Score (KOOS) was collected preoperatively and at 1, 2, and 5 years postoperatively. Patients who underwent revision ACLR at any institution in Sweden within 5 years of the primary surgery were identified in the Swedish National Knee Ligament Registry.Results:A total of 6104 patients (53.5% male) for whom knee range of motion measurements were available were identified (hyperextension group [≤−5°]: 2350 [38.5%]; mean extension, −6.1°± 2.3° [range, −20° to −5°]; no hyperextension group [>−5°]: 3754 [61.5%]; mean extension, 0°± 1.4° [range, −4° to 15°]). There were no intergroup differences in anterior knee laxity preoperatively (hyperextension group, 3.6 ± 2.8 mm; no hyperextension group, 3.7 ± 2.7 mm; P = .24) or postoperatively (hyperextension group, 1.8 ± 2.3 mm; no hyperextension group, 1.8 ± 2.2 mm; P = .41). The only significant but nonclinically relevant intergroup differences were seen in the KOOS Symptoms subscale at the 1-year follow-up (hyperextension group, 81.4 ± 16.0; no hyperextension group, 80.3 ± 16.5; P = .03) and in the Sport and Recreation subscale at the 5-year follow-up (hyperextension group, 73.0 ± 25.6; no hyperextension group, 75.7 ± 24.3; P = .02). No other significant intergroup differences were noted preoperatively or at 1, 2, or 5 years postoperatively in any of the KOOS subscales. The overall revision ACLR rate at ≤5 years after the primary surgery was 4.9% (302 of 6104 patients). The hazard for revision ACLR in the no hyperextension group (4.5%; 170 of 3754 patients) was not significantly different from that in the hyperextension group (5.6%; 132 of 2350 patients) (hazard ratio, 0.89; 95% CI, 0.71 to −1.12; P = .34). A subsequent subanalysis showed that the hazard of revision ACLR in patients with no hyperextension was not significantly different from that of patients with ≤−10° of extension (5.8%; 27 of 467 patients) (hazard ratio, 0.91; 95% CI, 0.61 to 1.36; P = .65).Conclusion:Preoperative passive contralateral knee hyperextension (≤−5°) was not associated with postoperative anterior knee laxity, subjective knee function, or revision surgery ≤5 years after ACLR using HT autografts. Therefore, the presence of knee hyperextension alone should not be considered a contraindication per se for the use of HT autografts in ACLR.

中文翻译：

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生理性术前膝关节过伸与术后松弛、主观膝关节功能或腘绳肌腱自体移植术 ACL 重建后的翻修手术无关


背景： 人们担心生理性膝关节过度伸展可能与使用腘绳肌腱 （HT） 自体移植物的前交叉韧带重建 （ACLR） 后的劣质结果相关。目的： 评估对侧术前被动膝关节过度伸展 （≤−5°） 与术后膝关节前松弛、膝关节主观功能或使用 HT 自体移植术后翻修手术是否存在关联。研究设计： 队列研究;证据水平， 3.方法： 确定了 2005年1月1日至 2018年12月31日在瑞典斯德哥尔摩 Capio Artro 诊所使用 HT 自体移植术进行原发性 ACLR 的无伴韧带损伤的患者。根据术前对侧被动膝关节伸展程度，该队列分为高伸组 （≤−5°） 和无高伸组 （>–5°）。术前和术后 6 个月评估膝关节前松弛度 （KT-1000 关节计;134 N）。术前和术后 1 、 2 和 5 年收集膝关节损伤和骨关节炎结果评分 （KOOS）。在瑞典国家膝关节韧带登记处确定了初次手术后 5 年内在瑞典任何机构接受翻修 ACLR 的患者。结果： 共确定了 6104 例患者 （53.5% 男性） 可进行膝关节活动度测量 （高伸组 [≤−5°]： 2350 [38.5%];平均伸展，−6.1°± 2.3° [范围，−20° 至 −5°];无高伸组 [>−5°]： 3754 [61.5%];平均延伸，0°± 1.4° [范围，−4° 至 15°]）。术前膝关节前松弛无组间差异 （高伸组，3.6 ± 2.8 mm;无高伸组，3.7 ± 2.7 mm;P = .24）或术后（高伸组，1.8 ± 2.3 毫米;无高伸组，1.8 ± 2.2 mm;P = .41）。唯一显着但无临床相关性的组间差异是在 1 年随访时的 KOOS 症状分量表中观察到的 （高伸组，81.4 ± 16.0;无高伸组，80.3 ± 16.5;P = .03）和 5 年随访时的运动和娱乐分量表（高伸组，73.0 ± 25.6;无高伸组，75.7 ± 24.3;P = .02）。在任何 KOOS 分量表中，术前或术后 1 、 2 或 5 年均未观察到其他显著的组间差异。初次手术后 ≤ 5 年的总体翻修 ACLR 率为 4.9% （6104 例患者中的 302 例）。无高伸组（4.5%;3754 例患者中 170 例）的翻修 ACLR 风险与高伸组（5.6%;2350 例患者中 132 例）无显著差异（风险比，0.89;95% CI，0.71 至 -1.12;P = .34）。随后的亚分析显示，无过度伸展患者翻修 ACLR 的风险与伸展 ≤−10° 的患者（5.8%;467 例患者中的 27 例）没有显著差异（风险比，0.91;95% CI，0.61 至 1.36;P = .65）。结论： 术前被动对侧膝关节过伸 （≤−5°） 与术后膝关节前松弛、主观膝关节功能或使用 HT 自体移植术后 ≤ACLR 5 年翻修手术无关。因此，不应仅将膝关节过伸的存在视为在 ACLR 中使用 HT 自体移植物的禁忌症。