An underactive thyroid can cause neck pain, though the connection is less straightforward than most people assume. The pain does not always come from the thyroid gland itself. It can arise from inflammation within the gland, from the muscular and nerve problems that low thyroid hormones create throughout the body, or from autoimmune conditions like Hashimoto’s thyroiditis that both damage the thyroid and sensitize the body’s pain pathways. The link between hypothyroidism and neck discomfort involves several distinct mechanisms, some common and some rare, and understanding which one applies to you changes what you should do about it.
When the Thyroid Gland Itself Hurts
The thyroid sits at the front of the neck, wrapped around the windpipe just below the Adam’s apple. When it becomes inflamed or enlarged, the pain tends to be felt in the front of the neck and sometimes radiates up toward the ears or jaw. A systematic review of local symptoms in Hashimoto’s thyroiditis found that anywhere from a tiny fraction to about 16% of patients experienced pain in the front of their neck, with some patients developing what researchers call “painful Hashimoto’s thyroiditis,” a subtype marked by acute, sometimes unbearable pain on one side or across the entire thyroid area.1Frontiers in Endocrinology. Local symptoms of Hashimoto’s thyroiditis: A systematic review One proposed explanation for this pain is that the thyroid capsule stretches rapidly as the gland swells, triggering nerve endings in the surrounding tissue.
Gland size matters here. A study of patients with compressive thyroid symptoms found that those with symptoms had an average gland volume roughly twice that of symptom-free patients. Interestingly, the presence of inflammation alone did not predict who had compressive symptoms; it was the physical bulk of the gland that mattered.2PubMed. Thyroid disease and compressive symptoms So a person with Hashimoto’s whose gland is gradually enlarging into a goiter can develop neck pressure and pain simply from the mass effect, regardless of whether the inflammation itself is particularly active at the time.
Case reports illustrate how persistent and disruptive this pain can become. One described a 42-year-old woman with a three-year history of Hashimoto’s who developed recurrent anterior neck pain radiating to both ears along with a tender, enlarging goiter. Her pain was severe enough that she ultimately underwent thyroidectomy for relief.3PubMed Central. Recurrent Painful Hashimoto Thyroiditis Successfully Treated by Thyroidectomy Another case documented a patient with Hashimoto’s who presented with neck pain radiating to the right ear that persisted for two months, with tenderness over the right thyroid lobe, complicated by subacute thyroiditis developing on top of the existing autoimmune condition.4PubMed Central. Should neck pain in a patient with Hashimoto’s thyroiditis be underestimated?
Subacute Thyroiditis and Its Hypothyroid Phase
Subacute thyroiditis is a different beast from Hashimoto’s, though the two can overlap. It is typically triggered by a viral infection and causes fever, significant neck pain, and disrupted thyroid hormone levels. Most patients first go through a hyperthyroid phase as stored hormone spills out of damaged thyroid cells, but the disease can progress into a hypothyroid phase where the gland is depleted and thyroid levels drop. A case report described a 34-year-old woman who presented with neck pain and headache, with tenderness over the right thyroid lobe, and whose lab work showed she was already in the hypothyroid stage of subacute thyroiditis.5PubMed Central. Neck Pain and Symptomatic Hypothyroidism: An Atypical Presentation of Subacute Thyroiditis
This matters because people sometimes assume that if their thyroid levels are low, the pain cannot be coming from thyroiditis. In fact, the neck pain from subacute thyroiditis can persist well into the hypothyroid stage. The gland is still inflamed and tender even after it has burned through its hormone stores. If you are hypothyroid and have a tender, painful front-of-neck, subacute thyroiditis in its later phase is a real possibility your doctor should consider.
Muscle Aches and Stiffness from Low Thyroid Hormones
Beyond the gland itself, hypothyroidism affects muscles throughout the body in ways that can produce neck pain. A prospective study of hypothyroid patients found that 79% had neuromuscular complaints, about 38% had measurable muscle weakness, and roughly 42% showed signs of nerve-and-muscle damage on electrical testing.6PubMed. Neuromuscular findings in thyroid dysfunction: a prospective clinical and electrodiagnostic study Muscle cramps, aches, stiffness, and exercise intolerance are well-recognized features of untreated hypothyroidism, and in some patients, pain is the only presenting symptom that points toward the thyroid as the culprit.7PubMed Central. Pain as a presenting symptom of hypothyroidism
The neck is especially vulnerable because it contains dense layers of muscle that support the head and enable movement. When those muscles are stiff, weak, or prone to cramping due to low thyroid hormones, the result can feel like ordinary musculoskeletal neck pain. A person might see a chiropractor or a physical therapist without anyone thinking to check their thyroid. A rare but dramatic form of this is Hoffmann’s syndrome, a subtype of hypothyroid myopathy characterized by muscles that look enlarged but are actually weak and stiff.8PubMed Central. A Rare Manifestation of Hypothyroid Myopathy: Hoffmann’s Syndrome Most people with hypothyroid-related muscle pain will not develop anything this severe, but the underlying principle is the same: low thyroid hormones impair how muscles contract and recover, producing chronic discomfort.
A study comparing Hashimoto’s patients to healthy controls found that the thyroid patients had significantly higher levels of both physical fatigue and pain perception.9PubMed Central. Physical fatigability and muscle pain in patients with Hashimoto thyroiditis This was not just about weakness; the patients actually experienced pain more intensely, suggesting that the autoimmune process itself may change how the nervous system processes pain signals.
Nerve Damage and Peripheral Neuropathy
Hypothyroidism can damage peripheral nerves, which adds another route to neck and upper-body pain. The neuropathy that develops in hypothyroid patients can mimic the symptoms of a pinched nerve from a disc problem or spinal stenosis, making it hard to tell apart without testing.7PubMed Central. Pain as a presenting symptom of hypothyroidism A genetic analysis using data from people of European ancestry found that hypothyroidism was significantly associated with a higher likelihood of nerve root and plexus disorders, as well as carpal tunnel syndrome.10Frontiers in Endocrinology. Causal relationship between hypothyroidism and peripheral neuropathy: a Mendelian randomization study of European ancestry Nerve root problems in the cervical spine produce neck pain that can radiate into the shoulders and arms, and if hypothyroidism is raising the odds of these disorders, it could explain why some hypothyroid patients have persistent neck pain that does not seem to match any structural problem on imaging.
There is also the phenomenon of referred pain through the vagus nerve. Arnold’s nerve, a branch of the vagus, connects sensation from the ear canal to structures in the throat and neck. Thyroid diseases can trigger referred ear pain via this pathway, and the reverse is also possible: thyroid-related irritation can produce pain that feels like it is coming from somewhere else entirely.11PubMed Central. Referred otalgia in patients with thyroid cancer: Case series from Saudi Arabia If you have an underactive thyroid and unexplained ear pain alongside neck pain, the two symptoms may share a single cause.
Fibromyalgia and Chronic Widespread Pain
The overlap between autoimmune thyroid disease and fibromyalgia is striking and underappreciated. Autoimmune thyroid disease is recognized as a cause of fibromyalgia and chronic widespread pain, with mechanisms that include inflammatory mediators, damage to small nerve fibers, and changes in how the brain processes pain signals.12PubMed. Fibromyalgia and chronic widespread pain in autoimmune thyroid disease One study found that about 41% of fibromyalgia patients had at least one thyroid antibody, and those with thyroid autoimmunity had a higher prevalence of symptoms like allodynia, where even light touch feels painful.13PubMed. Association between thyroid autoimmunity and fibromyalgic disease severity
Looking at the relationship from the other direction, a study of patients already diagnosed with Hashimoto’s thyroiditis found that 62% also met the criteria for fibromyalgia. The likelihood of having both conditions rose with higher thyroid antibody levels, longer disease duration, and higher TSH values.14PubMed. Fibromyalgia in patients with thyroid autoimmunity: prevalence and relationship with disease activity Fibromyalgia characteristically produces pain in the neck and shoulders along with many other body areas, so a person with hypothyroidism who has diffuse neck and body pain may be dealing with fibromyalgia as a consequence of their thyroid condition rather than a separate, coincidental problem.
This is an area where the evidence gets thin on exactly what to do about it. Treating the hypothyroidism with levothyroxine helps some patients’ pain but does not always resolve fibromyalgia symptoms, since the central sensitization that drives fibromyalgia can become self-sustaining once established. Recognizing the connection matters because it changes the management approach: treating just the thyroid numbers may not be enough if fibromyalgia has set in.
Thyroid Nodules That Bleed
A less common but dramatic cause of thyroid-related neck pain is spontaneous hemorrhage into a thyroid nodule. Thyroid nodules are extremely common, present in a large fraction of adults if you look with ultrasound, and the vast majority cause no symptoms. Occasionally, though, a nodule bleeds internally. A review of reported cases found that about 61% of patients with hemorrhagic thyroid nodules presented with acute neck pain or swelling, while roughly 29% had difficulty swallowing and about 10% had trouble breathing.15PubMed Central. Spontaneous hemorrhagic thyroid nodule: a case report and review of the literature This kind of neck pain comes on suddenly and is usually accompanied by visible or palpable swelling at the front of the neck. It is an acute event rather than a chronic ache, and it typically sends people to the emergency room rather than to their primary care doctor for routine thyroid follow-up.
Riedel’s Thyroiditis
At the rare end of the spectrum sits Riedel’s thyroiditis, a condition in which the thyroid gland gradually turns into dense, fibrous scar tissue. The gland becomes rock-hard on examination, and the fibrosis can extend into surrounding neck structures, compressing nerves and the airway. One case described a woman who became hypothyroid within weeks and then developed increasingly severe neck pain and compressive symptoms over the following months as her goiter hardened.16The Journal of Clinical Endocrinology & Metabolism. Riedel’s Thyroiditis: Report of a Case Complicated by Spontaneous Hypoparathyroidism, Recurrent Laryngeal Nerve Injury, and Horner’s Syndrome A review of patients with Riedel’s thyroiditis confirmed that the condition leads to pain and hypothyroidism, and in some cases also to vocal cord paralysis and other complications from the relentless fibrotic process.17PubMed Central. Riedel’s thyroiditis: clinical presentation, treatment and outcomes Among patients whose thyroid status was documented, about 46% were hypothyroid.18The Journal of Clinical Endocrinology & Metabolism. Riedel Thyroiditis Riedel’s is genuinely rare, but it is worth knowing about because the neck pain it produces is progressive and does not respond to standard thyroid treatment alone.
How Treatment Affects Pain Recovery
For muscle and nerve symptoms caused directly by low thyroid hormone levels, starting levothyroxine helps most people. In the prospective study that documented neuromuscular problems in hypothyroid patients, treatment over the course of a year resolved weakness in most, though about 13% still had residual muscle weakness after twelve months of adequate thyroid hormone replacement.6PubMed. Neuromuscular findings in thyroid dysfunction: a prospective clinical and electrodiagnostic study In case reports where pain was the primary symptom of undiagnosed hypothyroidism, starting thyroxine produced significant improvement.7PubMed Central. Pain as a presenting symptom of hypothyroidism
The picture is more complicated when the pain comes from the gland itself. Painful Hashimoto’s thyroiditis sometimes responds to corticosteroids or anti-inflammatory drugs, but recurrent cases occasionally require partial or total thyroidectomy. For subacute thyroiditis, the natural course is usually self-limiting over weeks to months, with anti-inflammatory medications managing the pain in the interim. Riedel’s thyroiditis typically requires a combination of surgery and immunosuppressive therapy because the fibrosis does not reverse on its own.
The practical point is that “neck pain from an underactive thyroid” is not one diagnosis. It spans a range from easily treated with a daily pill to requiring surgery, depending on the mechanism driving the pain. If you have neck pain and hypothyroidism and the pain does not improve as your thyroid levels normalize on medication, it is worth pushing for further evaluation rather than assuming the pain is unrelated or that you just need to wait longer.
Neck Pain After Thyroid Surgery
People who undergo thyroid surgery for any reason, whether for cancer, large goiters, or refractory thyroiditis, frequently end up with neck pain afterward. A cross-sectional study found that neck pain was the most common complaint after thyroid surgery, reported by about 52% of patients, ahead of voice changes and swallowing difficulty.19PubMed Central. The Underreported Postoperative Suffering after Thyroid Surgery: Dysphagia, Dysphonia, and Neck Pain A separate case-control study examining patients six months after thyroidectomy found they had significantly reduced neck range of motion, more trigger points in their neck and shoulder muscles, greater pain intensity, and more functional disability compared to healthy controls.20PubMed. Musculoskeletal neck disorders in thyroid cancer patients after thyroidectomy
The trigger points clustered in predictable muscles: the scalenes, the sternocleidomastoids running along the sides of the neck, the upper trapezius across the top of the shoulders, and the suboccipital muscles at the base of the skull. These are muscles that get retracted and stressed during thyroid surgery, and they can develop chronic pain patterns that persist long after the surgical wound has healed. Since thyroidectomy patients become hypothyroid and require lifelong thyroid hormone replacement, they are living with both surgical and hormonal contributors to neck pain simultaneously. Physical therapy targeting these specific muscles can help, but this post-surgical neck pain is frequently underrecognized and undertreated.