Biswas Sayan, Kumar Karan, Joy Praisy, Gaikwad Manisha R
Department of Anatomy, All India Institute of Medical Sciences, Bhubaneswar, IND.
Cureus. 2025 Apr 30;17(4):e83277. doi: 10.7759/cureus.83277. eCollection 2025 Apr.
Tensor fascia suralis is a rare supernumerary muscle in the posterior thigh and leg, with a male preponderance as reported in the literature. We present a unique Type Ia variant discovered during cadaver dissection of the left lower limb, originating from the long head of the biceps femoris and terminating at the medial head of the gastrocnemius. Unlike previously reported cases, this variant exhibited two distinct fleshy muscle bellies at origin and insertion, separated by an intermediate tendon. Both bellies received innervation from the tibial nerve, with the upper belly supplied directly via the sciatic nerve and the lower belly via a branch penetrating the gastrocnemius. This anomaly has significant clinical implications, potentially mimicking soft tissue tumors on imaging or contributing to nerve compression syndromes. Awareness of such variants is crucial for accurate diagnosis and optimizing surgical outcomes in posterior thigh and leg procedures.
腓肠肌筋膜张量是大腿后部和小腿中一种罕见的额外肌肉，文献报道男性居多。我们展示了在左下肢尸体解剖过程中发现的一种独特的Ia型变异，它起源于股二头肌长头，止于腓肠肌内侧头。与先前报道的病例不同，这种变异在起点和止点处表现出两个明显的肉质肌腹，由中间肌腱隔开。两个肌腹均由胫神经支配，上肌腹直接由坐骨神经供应，下肌腹由一条穿透腓肠肌的分支供应。这种异常具有重要的临床意义，在影像学上可能会模仿软组织肿瘤，或导致神经压迫综合征。认识到这种变异对于大腿后部和小腿手术的准确诊断和优化手术结果至关重要。
