Vastus Medialis (left) — SENIAM EMG Electrode Placement

Recording notes & source

per Criswell 2011, site „Vastus Medialis (Oblique)“, p. 366

Placement type: Specific site The signal originates predominantly from this muscle.
Signal check: Seated: extend the knee; standing: partial squat.
Crosstalk from: rectus femoris · adductor longus · adductor magnus

The position above follows SENIAM; the crosstalk and artefact notes apply to surface recording of this muscle in general.

Print as a session sheet · A4 with landmarks, signal check and MVC test

Source: SENIAM (Hermens 2000) ↗

Hermens HJ, Freriks B, Disselhorst-Klug C, Rau G. Development of recommendations for SEMG sensors and sensor placement procedures. J Electromyogr Kinesiol. 2000;10(5):361-74.

Based on SENIAM recommendations (Hermens et al. 2000). Not an official SENIAM product. See all references → · SENIAM reference table · How electrodes are placed (guide) · Glossary

Go deeper MVC Normalisation — Why Microvolts Alone Say Nothing → Why the Electrode Must Not Sit on the Innervation Zone →

All 49 muscle protocols as a PDF — free

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. Vastus Medialis (Vastus Medialis) is a muscle of the thigh anterior region. It is responsible for knee extension, medial patellar stabilization (VMO - important for patellar tracking). This muscle is one of 26 with official SENIAM-recommended surface EMG electrode placement. This page documents the exact electrode position, anatomical attachments and a standardized test movement based on Hermens et al. (2000).

Function Knee extension, medial patellar stabilization (VMO - important for patellar tracking) Origin Medial lip of the linea aspera, intertrochanteric line (distal) Insertion Medial border of the patella -> via patellar ligament to the tibial tuberosity Innervation Femoral nerve, L2–L4

Innervation after Perotto AO, Anatomical Guide for the Electromyographer, 5th ed. 2011 — an anatomical reference, not an electrode placement recommendation.

Clinical applications (SENIAM)

Knee rehabilitation (ACL, meniscus)
Quadriceps activation after surgery
Sports performance monitoring

Test Movement

Terminal knee extension (last 15 degrees) against resistance

Detail: group test, sensor on the reference muscle of the group (M. Rectus Femoris) — Group test — image shows the reference muscle of the group (M. Rectus Femoris). Illustration shows the left side; the set-up is mirrored for the right side.

MVC reference test (Konrad 2005)

Position: Seated, single-leg knee extension held between 90° and 70° knee flexion.
Fixation: Thigh and pelvis fixed on the seat; a strap at the ankle holds the knee angle.
Resistance: Fixed strap at the ankle, extension against it.

Konrad: an easy and beneficial exercise for all quadriceps muscles (rectus femoris, vastus lateralis, vastus medialis).

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. Vastus Medialis 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 Vastus Medialis is typically recorded to track progress and retrain activation.

EMG biofeedback in physiotherapy → What is EMG biofeedback? PicoBlue sensors

Frequently Asked Questions

Where do I place the EMG electrode on the M. Vastus Medialis?

80% on line from ASIS to the joint space in front of the anterior border of the medial ligament. Orientation: Almost perpendicular to that line. Based on the official SENIAM recommendations (Hermens et al. 2000).

Which test movement activates the M. Vastus Medialis?

Terminal knee extension (last 15 degrees) against resistance. This movement is part of the SENIAM protocol for standardized contraction verification.

Is the M. Vastus Medialis a SENIAM-recommended muscle?

Yes. The M. Vastus Medialis is one of 26 muscles for which the SENIAM project has published official surface EMG electrode placement recommendations.

M. Vastus Medialis

Electrode Placement (SENIAM)