B8 The medial femoral cutaneous nerve often innervates part of the "classical saphenous nerve territory" on the medial lower leg and medial malleolus. (11th August 2022)

• Record Type: Journal Article
• Authors: Bjørn, S; Jensen, AE; Nielsen, TD; Jessen, C; Petersen, JAK; Moriggl, B; Hörmann, R; Nyengaard, J; Bendtsen, TF
• Is Part Of: Regional anesthesia and pain medicine. Volume 47(2022)Supplement 1
• Page Start: A86
• Page End: A87
• Publication Date: 2022-08-11
• Subjects: Conduction anesthesia -- Periodicals; Pain medicine -- Periodicals; 617.964
• DOI: 10.1136/rapm-2022-ESRA.84
• Languages: English
• ISSNs: 1098-7339

Abstract

Abstract : Background and Aims: The saphenous nerve (SN) is described as innervating the anteromedial knee area, the medial part of the lower leg and the medial malleolus (MM), sometimes extending to the medial foot 1 . However, it has been shown that the anteromedial knee area is most often innervated by the medial femoral cutaneous nerve (MFCN) 2 . Furthermore, a sub-study of data from a recent volunteer trial showed that the MFCN (anterior or posterior branch (MFCN-A, MFCN-P)) often innervates part of the "classical saphenous nerve territory" on the medial lower leg, sometimes including the MM 3 . This knowledge is important for correct diagnosis and treatment of chronic neuropathic pain in this area. The primary aim was to explore the distal cutaneous innervation of the MFCN. Methods: Post-hoc analysis was performed on photographic material from a recently concluded randomized, double-blind volunteer trial. 3 Extensive photo documentation of the areas of cutaneous anesthesia after SN block and MFCN block or selective MFCN-A block was reviewed in order to characterize the sensory distribution of the MFCN. 3 The medial lower leg (MLL) was defined as the anteromedial crus distal to the tibial tuberosity. Results: The non-selective MFCN block anesthetized part of the MLL in 67% and the MM in 28%. Selective MFCN-A block anesthetized part of the MLL in 67% and the MM in 13% ( figure 1–3 ). Conclusions: In the majority of cases, the MFCN seems to innervate part of the classical saphenous nerve territory on the medial lower leg. This knowledge is important for correct diagnosis and treatment of acute pain or chronic neuropathic pain.