Numbness in the Upper Left Back

If you feel numbness in the back or a tingling feeling in the back, a number of things could be causing it. Potential causes range from common issues that are easy to resolve, like muscle strain, to more severe medical conditions such as cervical spondylotic myelopathy.

If you consistently feel numbness or tingling in your back, it's best to consult your doctor about your symptoms.

Read more: What Causes Left Back & Shoulder Pain?

According to the Mayo Clinic, strained muscles can sometimes present with numbness or tingling in your back, but you should consult a doctor if you experience either of those symptoms. A strained muscle happens when you accidentally damage part of your muscle, sometimes because you didn't sufficiently warm up or stretch before working out or playing sports.

Muscles in your upper left back and shoulder that you could potentially strain include your rhomboid, trapezius, deltoid or infraspinatus. You can treat a strained shoulder muscle by following the RICE protocol: Rest, ice, compression and elevation.

Another cause could be an injury to your brachial plexus, a bundle of nerves that carries signals between your spinal cord and your shoulder, arm and hand. Injuries from contact sports or other accidents can compress, stretch or even tear these nerves.

Symptoms of a brachial plexus injury include an "electric shock" or burning feeling running down your arm, numbness, weakness and pain. To treat a brachial plexus injury, your doctor will likely recommend physical therapy. Some severe cases may require surgery.

Read more: Causes of Lower Left Side Abdominal and Back Pain

According to the American Heart Association, most heart attacks present as chest pain, but potential symptoms include pain or discomfort in one or both arms, your neck, your stomach or your back. Other heart attack symptoms include shortness of breath, nausea, breaking out into a cold sweat and clamminess. Most heart attack symptoms occur in the center or left side of your torso.

Women are more likely to experience upper back pressure during a heart attack than men, and some women having a heart attack will not feel chest pressure at all. This causes them to chalk up their symptoms to the flu or a minor health issue like acid reflux, rather than seeking help for a heart attack.

If you notice a tingling or numbness in your back and also your neck, you may be experiencing a condition called cervical spondylotic myelopathy (CSM). CSM happens when your spinal cord becomes compressed, usually because of degenerative changes in your spine due to age.

Treatments for CSM include going to physical therapy, wearing a soft cervical collar, taking medications to mediate your symptoms or potentially undergoing surgery to relieve pressure on your spinal cord.

Another condition causing upper back numbness is thoracic outlet syndrome (TOS). TOS is caused by the compression of arteries and/or veins, the nerves between your shoulder and your neck, or a combination of both issues.

The Hospital for Special Surgery describes the most common symptom as "pain, numbness and tingling that radiates below the shoulder down towards the hand and usually into the pinky and ring finger."

Other TOS symptoms include weakness, muscle wasting and a loss of fine motor skills. Treatment for TOS varies depending on the severity of the condition, but options include posture changes, weight loss, anti-inflammatory medications and surgery.