Nerve Blocks

The axillary nerve wraps around the back of the upper arm bone beneath the deltoid muscle. Along with the suprascapular nerve, it is an important part of the shoulder joint’s nerve supply, and the literature supports blocking it for pain after shoulder surgery and targeting it with denervation for chronic shoulder pain^[5]. In chronic pain practice it is most often combined with a suprascapular nerve block for shoulder arthritis, frozen shoulder or rotator cuff pain, especially when surgery is not an option or pain is holding back physical therapy.

This is not the same as the “axillary block” used for hand surgery, which numbs the brachial plexus in the armpit and does not actually block the axillary nerve^[7]. An axillary nerve block is done with ultrasound at the back of the shoulder: you sit or lie on your side, your physician finds the nerve beside its companion artery, and a thin needle places local anesthetic, sometimes with a steroid, next to it. Ultrasound shows the nerve, the vessels and the needle in real time, without radiation^[4]. Because the nerve also powers the deltoid, lifting your arm out to the side may feel weak for a few hours.

Evidence is still limited. In a randomized trial of 61 people with frozen shoulder, adding an axillary nerve block to a suprascapular nerve block gave faster and greater pain relief and better shoulder motion over follow-up than the suprascapular block alone^[6]. If blocks help but the relief fades, your physician may discuss radiofrequency ablation of the shoulder nerves.

The femoral nerve runs from the lower spine into the front of the thigh. It powers the quadriceps muscle and carries feeling from the front of the thigh and knee, which is why surgeons often use a femoral nerve block for thigh and knee operations^[8]. In a chronic pain practice, a full femoral nerve block is used more selectively — for example, as a diagnostic test when pain seems to come from the femoral nerve or its branches after an injury or surgery, or for short-term relief during a severe flare.

More often, chronic pain physicians block smaller branches that spare thigh strength: the femoral and obturator branches that supply the hip, the genicular nerves around the knee, or the saphenous nerve, which carries feeling from the inner leg and ankle and can be blocked while keeping the leg muscles working^[9].

The block is done lying on your back. Using ultrasound at the crease of the groin, your physician finds the femoral nerve beside the femoral artery and places local anesthetic, sometimes with a steroid, around it. The key safety issue is temporary quadriceps weakness: a 2026 meta-analysis of 31 surgical trials found that people who received a single femoral nerve block were more likely to fall than those who did not, with an absolute increase of about 0.9%^[10]. Bring a driver, use support when walking, and avoid stairs alone until your strength returns.

A peripheral nerve block is any injection of local anesthetic, with or without a steroid, next to a nerve outside the brain and spinal cord^[2]. In chronic pain practice, common targets include the lateral femoral cutaneous nerve for meralgia paresthetica — burning or numb skin on the outer thigh^[11] — and the ilioinguinal nerve for groin and upper-thigh pain after hernia or other lower-abdominal surgery, where ultrasound-guided blocks are used when conservative care is not enough^[12]. Nerves in the leg, ankle and foot can be blocked the same way for nerve pain after an injury or operation.

Most peripheral nerve blocks are done with ultrasound, which shows soft tissues, nearby blood vessels and the needle in real time and avoids radiation^[4]. Peripheral nerve blocks are rated low bleeding-risk procedures, so many people can continue their blood thinners — but only with their prescribing doctor’s agreement^[3]. A steroid may extend relief: in a randomized trial of 88 people with nerve pain after nerve injury, adding methylprednisolone to lidocaine gave significantly better pain relief at three months than lidocaine alone^[13].

If a block helps but the relief is short-lived, the result can guide longer-lasting options such as radiofrequency ablation, cryoneurolysis or peripheral nerve stimulation of the same nerve^[2].