Criswell E. Cram's Introduction to Surface Electromyography. 2nd ed. Jones & Bartlett Learning; 2011. ISBN 978-0-7637-3274-5.
Methodological background of the source
Criswell (2011) — Cram's Introduction to Surface Electromyography, 2nd edition — is the standard textbook for surface EMG electrode placement beyond the SENIAM catalogue. Its atlas section (Part III) describes, for each site, palpation, electrode location with 2 cm spacing parallel to the fibres, a behavioural test and the neighbouring muscles from which crosstalk is to be expected. Cram's classifies the position used here as "quasi-specific" — the muscle cannot be fully separated from its neighbours at the surface. The position is established in practice but less validated than a SENIAM recommendation.
Print-ready for the lab or clinic: 77 pages of protocols (SENIAM + peer-reviewed), plus the SENIAM table, a placement checklist and a sensor comparison sheet as A4 sheets.
Anatomy & Function
The M. Adductor Longus (Adductor Longus) is a muscle of the hip region. It is responsible for hip adduction, flexion and external rotation. This muscle is not covered by the official SENIAM catalogue — placement is based on established clinical literature. This page documents the exact electrode position, anatomical attachments and a standardized test movement based on Hermens et al. (2000).
FunctionHip adduction, flexion and external rotationOriginSuperior ramus of the pubis, ventral to the symphysisInsertionLinea aspera of the femur (middle third)InnervationObturator nerve, L2–L4
Innervation after Perotto AO, Anatomical Guide for the Electromyographer, 5th ed. 2011 — an anatomical reference, not an electrode placement recommendation.
Test Movement
Thigh adduction in side-lying against resistance
This muscle has no SENIAM-standardized electrode position. Placement should be based on anatomical knowledge.
Illustration shows the left side; the set-up is mirrored for the right side.
MVC reference test (Konrad 2005)
Position
Supine or seated with flexed legs; a big, stiff roll cushion is pressed between the knees.
Fixation
The cushion itself provides the rigid resistance; pelvis stable.
Resistance
Isometric adduction against the cushion.
Konrad tests the adductors as one group ("Mm. adductores"); surface EMG does not separate longus, magnus and gracilis.
Konrad P. The ABC of EMG. Noraxon; 2005, p. 32. Konrad describes this test at group level; it applies to all muscles of the group. · Why and how to normalise to MVC
Measure M. Adductor Longus activity live
The electrode is placed — what next? easyEMG visualises muscle activity in real time, with SENIAM-compliant placement guidance, up to 4 channels at once and biofeedback training right afterwards.
In rehabilitation, the Adductor Longus is typically recorded to track progress and retrain activation.
Where do I place the EMG electrode on the M. Adductor Longus?
Medial thigh, approx. 4 cm distal to the pubis; palpate the muscle belly during isometric adduction. Orientation: Oblique along the muscle course, 2 cm inter-electrode distance; avoid the anterior midline of the thigh (crosstalk from rectus femoris). Not covered by SENIAM — placement per Criswell 2011.
Which test movement activates the M. Adductor Longus?
Thigh adduction in side-lying against resistance. It serves as a signal check before recording: with correct electrode placement the EMG amplitude rises clearly during this movement.
Is the M. Adductor Longus a SENIAM-recommended muscle?
No. The M. Adductor Longus is not included in the official SENIAM catalogue. The electrode position documented here follows the established protocol per Criswell 2011.
Preview — open the 3D viewer to rotate the model and check neighbouring muscles.
View in 3D Viewer
