Is Your Back Causing Shoulder Pain?

Very common, and more frequent than one might expect. Studies show that 15–55% of patients presenting with predominant shoulder pain may actually have a primary cervical spine source:

1. A 2020 study demonstrated that up to around 50% of patients with shoulder pain being evaluated have some component of cervical disease and radiculopathy contributing to or causing their symptoms(1).
2. Patients with severe and treatment resistant tennis or golfer’s elbow commonly have disease sourced from the cervical spine(2).
3. A confirmatory test for cervical source of atraumatic shoulder pain is a cervical nerve root block (the gold standard) which can improve the majority of pain symptoms when property done under imaging guidance(3).
   Bottom line: If your shoulder MRI is “normal” or only shows mild age-related changes, the neck is a very real possibility.

Symptom Location and Quality – The Dermatome Map Matters

The C5 and C6 nerve roots are the most common culprits for shoulder-area referred pain. The fifth cervical root (C5) causes pain over the lateral shoulder and upper arm (deltoid region). The sixth cervical root (C6) causes pain over the biceps, lateral forearm, thumb, and index finger. However, sometimes the symptoms from cervical radiculopathy do not always have to radiate distally down the arm below the elbow. Sometimes the referred pain from the cervical disease is confined to just the shoulder itself, although other areas such as the armpit or shoulder blade frequently become painful as well (not always).

Patients often say “my shoulder hurts,” but point to the top, back, or outer part of the shoulder — exactly where C5 dermatome pain is felt. In contrast, rotator cuff tendinopathy or tears typically cause pain in the anterolateral arm just below the deltoid, often described as a deep ache worsened by reaching overhead or behind the back.

Experienced shoulder surgeons such as Dr. Thomas Obermeyer and spine specialists use a few quick tests to separate the two. It should be noted no examination test in isolation is perfect and false negatives and false positive tests are not uncommon depending on the pain severity and the individual patient’s response to the disease process.

1. Spurling’s Test (foraminal compression test) – While not a great screening test (low sensitivity at around 30-40%), if positive it is very specific(4). If turning and tilting your head toward the painful side reproduces your shoulder or arm pain, this strongly suggests a cervical source.
2. Pain with Provocation (Neer/Hawkins) – Positive in true rotator cuff disease, usually negative or inconsistent in pure cervical radiculopathy.
3. Rotator Cuff Strength Testing – True weakness (especially external rotation or supraspinatus) points to rotator cuff tear. “Pseudoweakness” from pain inhibition is common in cervical radiculopathy but improves with distraction or cervical traction.

Diagnostic tests, much like physical examination findings, are also imperfect. This is especially the case in older patients which frequently have incidental “wear and tear” type changes that do not always relate to symptoms. As example, patients with shoulder pain from a cervical nerve disorder may have changes in the tendon or labrum of the shoulder reported on MRI but if a scan were to be performed on the other painless side the same changes would be detected.

1. Shoulder X-rays & MRI – Excellent for rotator cuff tears/bone spurs, arthritis, calcific tendinitis. Normal or mild findings do not rule out a cervical source.
2. Cervical MRI – The single most useful test when history/exam suggests neck origin. Look for foraminal stenosis at C4-5 (C5 root) or C5-6 (C6 root). Disc herniations and spondylotic foraminal narrowing are common.
3. Diagnostic Cervical Selective Nerve Root Block – The gold-standard confirmatory test. If injection of local anesthetic around the suspected nerve root (usually C5 or C6) abolishes your shoulder pain for the duration of the anesthetic, the diagnosis is confirmed(1). This is dependent on a qualified proceduralist doing the cervical injection in exactly the right place.
4. EMG/Nerve Conduction Studies – Helpful only in advanced cases, especially when weakness or sensory loss is present. Normal in a large portion of cervical sensory (pain only) radiculopathies. In patients with later confirmed cervical nerve disease, it is positive in only 42% of cases(6).

If you have shoulder pain and any of the following, ask your doctor to evaluate your neck.

• Pain started without any injury and gets worse rapidly
• You have neck stiffness or pain with certain head positions
• Pain shoots below the elbow or into the hand
• A subacromial shoulder injection helped only briefly (or not at all)
• Your shoulder MRI is relatively normal for your age

Getting the right diagnosis early can save you months of ineffective physical therapy, unnecessary medications, and even avoidable surgery.