The femoral nerve splits into the anterior and the posterior branch
The femoral nerve innervates the muscles in the anterior compartment of the thigh
The anterior branch of the femoral nerve innervates the sartorius muscle – and sometimes the pectineus muscle
The posterior femoral nerve branch innervates most of the muscles in the anterior compartment of the thigh – i.e. the quadriceps femoris (the rectus femoris and the three vastus muscles)
Before the femoral nerve emerges from under the inguinal ligament it also innervates the iliac muscle and the femoral artery
The quadriceps femoris muscle is innervated by the posterior femoral nerve branch. The quadriceps femoris muscle and the sartorius muscle are both depicted in turquoise colour. The sartorius muscle is innervated by the anterior femoral nerve branch.
The femoral nerve runs below the iliacus fascia and on top of the iliacus muscle
The figure shows the femoral nerve in cross section in green underneath the iliacus fascia. The femoral nerve is on top of the iliacus muscle (yellow asterix). Red profile = femoral artery. Blue profile = femoral vein. Cyan asterix = psoas major muscle tendon. Green asterix = pectineus muscle.
Before inserting the needle through the skin, the hose and the needle should be filled with saline or local anaesthetic
Just after insertion of the needle 1/2 ml of fluid should be flushed through the hose and needle to make sure that no air is contained in the “system”
Click on the VIDEO CLIP button to view the video
The video shows the blurring effect of injected air during the performance of an infraclavicular nerve block A = axillary artery; MaP = major pectoral muscle; MiP = minor pectoral muscle
In the infraclavicular block the local anaesthetic should be injected periarterially in the seven o’clock position (seeing the axillary artery as a clock face)
However, it is often necessary to reposition the needle tip in order to inject local anaesthetic periarterially from the two o’clock position around the artery to the ten o’clock position
Click on the VIDEO CLIP button to view the video
Local anaesthetic is injected periarterially. lateral fascicle (LF); medial fascicle (MF); posterior fascicle (PF); axillary artery (A); local anaesthetic; (LA); minor pectoral muscle (MiP)
The medial cord is located between the axillary artery and vein around the two o’clock position of the artery
The local anaesthetic does not always spread around the artery to the two o’clock position from a seven o’clock point of injection
In that case the needle tip should be repositioned in front of the axillary artery to the interspace between the axillary artery and vein and local anaesthetic should be injected periarterially
Click on the VIDEO CLIP button to view the video
Periarterial injection of local anaesthetic between the axillary artery and vein in order to cover the medial cord of the brachial plexus MaP = major pectoral muscle; MiP = minor pectoral muscle; A = axillary artery; V = axillary vein
Repositioning of the needle tip is oftentimes necessary in order to cover all three cords around the axillary artery from two o’clock to ten o’clock
Care should be taken not to pierce the axillary vein
Click on the VIDEO CLIP button to view the video
In the video: Notice that local anaesthetic is injected on the wrong side of the clavipectoral fascia which has to be penetrated by the needle before local anaesthetic spreads appropriately around the medial cord
The video shows repositioning of the needle tip during an infraclavicular block First, local anaesthetic is injected around the lateral cord in the ten o’clock position Then, the needle is relocated in front of the axillary artery in order to reach the medial cord
The brachial plexus innervates the entire upper limb – except part of the skin of the upper half of the medial arm which is innervated by the intercostobrachial nerve
The intercostobrachial nerve is synonymous to the lateral cutaneous branch of the second intercostal nerve
The intercostobrachial nerve joins the medial cutaneous nerve of the arm to supply the skin of the upper half of the medial arm
The green colour depicts the intercostobrachial nerve which branches off as the lateral cutaneous nerve of the second intercostal nerve The intercostobrachial nerve is not part of the brachial plexus