Ito Naoaki, Martin Jack A, Joachim Mikel R, Blemker Silvia S, Opar David A, Kliethermes Stephanie A, Heiderscheit Bryan C, Baer Geoffrey, Fabian Kurrel, Hammer Erin, Heidt Danielle, Kuehl Matthew, Lee Kenneth, Moll Michael, Peot Ryan, Sanfilippo Jennifer, Tanaka Claire, Sund Sarah, Lin Yi-Chung, Hickey Jack, Homer Ashleigh, Maniar Nirav, Timmins Ryan, Cousins Matthew, DuCharme Olivia, Feng Xue, Nguyen Anthony, Riem Lara, Hart Joseph, McCoy Noah, Allred Dain, Beutler Anthony, Campbell Darren, Wayne Johnson A, Wilwand Malorie, Mortensen Brett, Remington Emma, Hauenstein Jonathon, Metoyer Casey, Wagle John, Huff Josh, Port Nicholas, Reyes Jordan
Department of Orthopedics and Rehabilitation, University of Wisconsin-Madison, Madison, Wisconsin, USA.
Badger Athletic Performance Program, University of Wisconsin-Madison, Madison, Wisconsin, USA.
Am J Sports Med. 2025 Mar;53(4):809-816. doi: 10.1177/03635465241313235. Epub 2025 Jan 28.
Quadriceps dysfunction is ubiquitous after anterior cruciate ligament (ACL) reconstruction (ACLR). Addressing quadriceps dysfunction is crucial to improve function, reduce the reinjury risk, and maintain long-term knee health. While deficits specific to the quadriceps are well documented, less is known about the effect of an ACL injury on other lower extremity muscle groups.
PURPOSE/HYPOTHESIS: The purpose of this exploratory analysis was to quantify and rank lower extremity muscle volume deficits using magnetic resonance imaging in collegiate football athletes after ACLR. It was hypothesized that the quadriceps muscles would present with the greatest deficits and that compensatory hypertrophy of muscles at adjacent joints such as the hip and ankle would be observed.
Cross-sectional study; Level of evidence, 3.
This study is a secondary analysis from an ongoing multicenter prospective cohort study involving Division I collegiate football athletes. Athletes who underwent primary unilateral ACLR (1 [3%] allograft, 2 [7%] quadriceps tendon autograft, 22 [73%] bone-patellar tendon-bone autograft, 5 [17%] hamstring tendon autograft) and magnetic resonance imaging were included. Muscle volumes (mL·kg·m) were quantified bilaterally from 38 lower extremity muscles using machine learning technology. Paired-samples tests were performed between limbs for each muscle, which were then ranked and visualized in a forest plot based on standardized mean differences (surgical - nonsurgical limb).
A total of 30 athletes (mean time from surgery, 27.9 ± 19.0 months) were included. The largest muscle volume deficits in the surgical limb were seen in the 3 uniarticular quadriceps muscles, followed by the biarticular triceps surae muscles. The rectus femoris and soleus did not show significant differences between limbs. Conversely, the fibularis muscle group had a greater muscle volume in the surgical limb compared with the nonsurgical limb. Most other muscle groups did not present significant differences between limbs.
Persistent quadriceps atrophy in a cohort of high-level athletes over 2 years after ACLR was highlighted in this study. Deficits in the gastrocnemius muscles, but not in the soleus, were also identified. This comprehensive approach examining various lower extremity muscles revealed latent muscle volume deficits present after ACLR.
前交叉韧带（ACL）重建（ACLR）后股四头肌功能障碍普遍存在。解决股四头肌功能障碍对于改善功能、降低再次受伤风险以及维持膝关节长期健康至关重要。虽然股四头肌的特定功能缺陷已有充分记录，但关于ACL损伤对其他下肢肌肉群的影响知之甚少。
目的/假设：本探索性分析的目的是使用磁共振成像对大学橄榄球运动员ACLR后的下肢肌肉体积缺陷进行量化和排名。假设股四头肌的缺陷最大，并且会观察到相邻关节（如髋部和踝部）的肌肉出现代偿性肥大。
横断面研究；证据等级，3级。
本研究是一项正在进行的多中心前瞻性队列研究的二次分析，该研究涉及一级大学橄榄球运动员。纳入接受初次单侧ACLR（1例[3%]同种异体移植物，2例[7%]股四头肌肌腱自体移植物，22例[73%]骨-髌腱-骨自体移植物，5例[17%]绳肌自体移植物）并进行磁共振成像的运动员。使用机器学习技术对38块下肢肌肉的双侧肌肉体积（mL·kg·m）进行量化。对每块肌肉的两侧肢体进行配对样本检验，然后根据标准化平均差异（手术侧肢体-非手术侧肢体）在森林图中进行排名和可视化。
共纳入30名运动员（手术平均时间为27.9±19.0个月）。手术侧肢体中最大的肌肉体积缺陷出现在3块单关节股四头肌中，其次是双关节小腿三头肌。股直肌和比目鱼肌两侧肢体之间未显示出显著差异。相反，与非手术侧肢体相比，手术侧肢体的腓骨肌群肌肉体积更大。大多数其他肌肉群两侧肢体之间未呈现显著差异。
本研究强调了ACLR后2年以上的高水平运动员队列中持续存在的股四头肌萎缩。还发现了腓肠肌而非比目鱼肌的缺陷。这种检查各种下肢肌肉的综合方法揭示了ACLR后存在的潜在肌肉体积缺陷。
