Durand Sébastien, Christen Thierry, Ledoux Jean-Baptiste, Baillot Romain
Department of Hand Surgery, Lausanne University Hospital, Rue du Bugnon 46, CH-1011 Lausanne, Switzerland.
Department of Diagnostic and Interventional Radiology, Lausanne University Hospital, University of Lausanne, CH-1011 Lausanne, Switzerland.
J Clin Med. 2023 Dec 21;13(1):46. doi: 10.3390/jcm13010046.
The original description of boxer's knuckle injury of the fifth ray mentions that the injury occurs between the extensor digitorum communis (EDC) and the extensor digiti minimi (EDM). Subsequent reports claim similar findings. Anatomical studies show that the EDC of the fifth ray is absent in most patients, while the EDM is generally composed of two slips. We present a modification of the current description of boxer's knuckle injury of the little finger based on the correlation between advanced preoperative 3D imaging and intraoperative findings.
Five patients were investigated preoperatively using high-resolution ultrasound and 3D tendon reconstruction-based MR arthrography. Surgical exploration identified the lesion site relative to the EDM and EDC.
All patients had two slips of the EDM and no EDC to the fifth ray. The injury appeared as a longitudinal tear of the EDM between its two slips. The mean gap was 7.8 mm (range 4.5-10 mm) on the pathological side vs. 1.3 mm (range 1-2 mm) on the healthy contralateral side.
We believe that previous descriptions of boxer's knuckle of the fifth ray are inaccurate. High-resolution ultrasound and 3D reconstructions based on MR arthrography are reliable diagnostic tools allowing to locate the injury with precision.
关于第五掌指关节拳击手损伤的最初描述提到，损伤发生在指总伸肌（EDC）和小指伸肌（EDM）之间。随后的报告也有类似发现。解剖学研究表明，大多数患者的第五掌指关节没有指总伸肌，而小指伸肌通常由两条肌腱束组成。我们基于术前先进的三维成像与术中发现之间的相关性，对目前关于小指拳击手损伤的描述进行了修正。
对5例患者术前采用高分辨率超声和基于三维肌腱重建的磁共振关节造影进行检查。手术探查确定了相对于小指伸肌和指总伸肌的病变部位。
所有患者的小指伸肌均有两条肌腱束，第五掌指关节没有指总伸肌。损伤表现为小指伸肌两条肌腱束之间的纵向撕裂。患侧平均间隙为7.8毫米（范围4.5 - 10毫米），而健侧对侧平均间隙为1.3毫米（范围1 - 2毫米）。
我们认为之前关于第五掌指关节拳击手损伤的描述不准确。基于磁共振关节造影的高分辨率超声和三维重建是可靠的诊断工具，能够精确地定位损伤部位。
