Background:Hamstring strain injuries (HSIs) are prevalent in US National Football League (NFL) players, but there is a paucity of information regarding imaging characteristics, injury severity, and player factors associated with time missed and risk of recurrent injury.Purpose:To describe player, football activity, clinical, and imaging characteristics of NFL players with HSIs, as well as determine player characteristics, clinical examination results, and magnetic resonance imaging (MRI) findings associated with injury occurrence, severity, and missed time.Study Design:Cross-sectional study; Level of evidence, 3.Methods:A retrospective cohort of NFL players with acute HSI (n = 180) during the 2018-2019 season was identified. Injury data were collected prospectively through a league-wide electronic health record system. Three musculoskeletal radiologists graded MRI muscle injury parameters using the British Athletics Muscle Injury Classification (BAMIC) system. Player, football, clinical, and imaging characteristics were correlated with HSI incidence and severity and with missed time from sport.Results:Of the 1098 HSIs identified during the 2018-2019 season, 416 (37.9%) were randomly sampled, and 180 (43.3%) had diagnostic imaging available. Game activity, preseason period, and wide receiver and defensive secondary positions disproportionately contributed to HSI. The biceps femoris was the most commonly injured muscle (n = 132, 73.3%), followed by the semimembranosus (n = 24, 13.3%) and semitendinosus (n = 17, 9.4%) muscles. The most common injury site was the distal third of the biceps femoris and semitendinosus muscles (n = 60, 45.5% and n = 10, 58.8%, respectively) and central part of the semimembranosus muscle (n = 17, 70.8%). Nearly half of the injuries (n = 83, 46.1%) were BAMIC grade 2; 25.6% (n = 46), grade 3; and 17.8% (n = 32), grade 4. MRI showed sciatic nerve abnormality in 30.6% (n = 55) of all HSIs and 81.3% (n = 26) of complete tendon injuries. BAMIC grade correlated with both median days and games missed. Combined biceps femoris and semitendinosus injuries resulted in the highest median days missed (27 days).Conclusion:Among NFL players with acute HSIs, the most common injury was a moderate-severity injury of the distal biceps femoris. BAMIC grade was associated with missed time.

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国家橄榄球联盟职业运动员腿筋拉伤的球员和影像特征与严重程度和缺席时间的相关性：回顾性研究


背景：腿筋拉伤 (HSI) 在美国国家橄榄球联盟 (NFL) 球员中很常见，但有关影像学特征、受伤严重程度以及与缺席时间和复发受伤风险相关的球员因素的信息很少。 目的：描述患有 HSI 的 NFL 球员的球员、足球活动、临床和影像特征，并确定与受伤发生、严重程度和缺席时间相关的球员特征、临床检查结果和磁共振成像 (MRI) 结果。研究设计：横断面研究；证据级别，3。方法：确定了 2018-2019 赛季期间患有急性 HSI 的 NFL 球员 (n = 180) 的回顾性队列。伤病数据是通过全联盟范围内的电子健康记录系统前瞻性收集的。三名肌肉骨骼放射科医生使用英国田径肌肉损伤分类 (BAMIC) 系统对 MRI 肌肉损伤参数进行分级。球员、足球、临床和影像特征与 HSI 发生率和严重程度以及错过运动时间相关。 结果：在 2018-2019 赛季期间发现的 1098 例 HSI 中，随机抽取了 416 例 (37.9%)，随机抽取了 180 例 (43.3%)。 %) 有可用的诊断成像。比赛活动、季前赛期间、外接手和防守次要位置对 HSI 的贡献不成比例。股二头肌是最常受伤的肌肉（n = 132，73.3%），其次是半膜肌（n = 24，13.3%）和半腱肌（n = 17，9.4%）。最常见的损伤部位是股二头肌和半腱肌的远端三分之一（分别为 n = 60, 45.5% 和 n = 10, 58.8%）和半膜肌的中央部分（n = 17, 70.8%）。近一半受伤 (n = 83, 46.1%) 为 BAMIC 2 级； 25.6% (n = 46)，3 级； 17.8% (n = 32)，4 级。MRI 显示所有 HSI 中 30.6% (n = 55) 和完全肌腱损伤中 81.3% (n = 26) 坐骨神经异常。 BAMIC 等级与中位天数和错过的比赛相关。股二头肌和半腱肌联合损伤导致中位缺席天数最高（27 天）。结论：在患有急性 HSI 的 NFL 球员中，最常见的损伤是远端股二头肌的中度严重损伤。 BAMIC 等级与错过的时间相关。