Endometriosis and Pelvic Pain: The Hidden Musculoskeletal Causes — and How Pelvic PT and Botox Can Help
Why pain can persist even after surgery or reassuring imaging — and what actually works
Sagittal view showing the pelvic floor (levator ani), obturator internus, abdominal wall, pudendal nerve, and pelvic organs where endometriosis commonly involves adjacent tissues.
Pelvic pain in women is often discussed in relation to gynecologic conditions such as endometriosis, adenomyosis, ovarian pathology, or pelvic inflammatory disease. That framing is important, but it is incomplete. In many women, pelvic pain is also shaped by the musculoskeletal system: the pelvic floor muscles, abdominal wall, hips, low back, pelvic girdle, fascia, and the nerves traveling through these structures.
This does not mean the pain is just muscular, and it does not minimize the role of endometriosis or other pelvic disease. It means that once pain becomes persistent, the body often responds in ways that amplify and maintain symptoms. For many patients, the musculoskeletal system becomes part of the pain generator.
Endometriosis may start the pain story. The musculoskeletal system may help explain why the story continues.
1. The Pelvic Floor Can Become Overactive and Painful
One of the most important musculoskeletal contributors to chronic pelvic pain is pelvic floor muscle dysfunction. The pelvic floor is not just a passive support structure. These muscles help with continence, bowel function, sexual function, posture, and load transfer through the trunk and pelvis. When they become tense, shortened, poorly coordinated, or tender, they can become a direct source of pain.
This process is often described as myofascial pelvic pain. In practical terms, it means the muscles and surrounding connective tissue develop areas of tenderness and irritability that can produce both local pain and referred pain. A patient may feel aching, pressure, burning, heaviness, pain with intercourse, pain with sitting, or pain during urination or bowel movements even when the original driver is not the pelvic floor itself.
A structured pelvic floor muscle examination can identify clinically meaningful tenderness, asymmetry, impaired relaxation, and reproduction of the patient’s symptoms. That matters because pain that appears deep pelvic may, in part, be arising from the levator ani, obturator internus, or adjacent myofascial tissues rather than from a pelvic organ alone.
2. How Endometriosis and Other Visceral Pain Triggers Muscle Guarding
A key mechanism in chronic pelvic pain is the transition from visceral pain to musculoskeletal pain amplification. When pelvic organs are inflamed, irritated, or painful — whether from endometriosis, bladder pain syndrome, irritable bowel symptoms, or another source — the body often responds with protective guarding.
Muscles tighten to protect the region. Initially, that may be adaptive. Over time, however, persistent guarding can become maladaptive. This is one reason pelvic pain may continue even after a lesion is treated or after imaging appears reassuring.
The original nociceptive input may have triggered a secondary musculoskeletal response that has now developed a life of its own. Muscles remain hypertonic. Connective tissues become less tolerant of stretch and pressure. Everyday movements become provocative. The pain system becomes more reactive.
For women with endometriosis, this concept is especially important. Endometriosis may be the initial driver, but it is not always the only ongoing driver. Recurrent inflammation, dyspareunia, pain anticipation, bracing, altered activity, and even postoperative guarding can all contribute to persistent pelvic floor and myofascial dysfunction.
An initial visceral trigger can progress through protective muscle guarding, myofascial pain, and neural sensitization, eventually engaging the central pain system. Once established, the musculoskeletal system helps maintain the pain independent of the original trigger.
3. Pelvic Pain Is Rarely Limited to the Pelvis
Another important point is that pelvic pain is often part of a broader regional musculoskeletal disorder rather than an isolated local problem. Studies comparing women with and without chronic pelvic pain have reported more frequent musculoskeletal dysfunction in the pain group. That dysfunction may involve the abdominal wall, the hips and hip rotators, the low back, the sacroiliac joints, the pelvic girdle, and surrounding fascia and connective tissue.
Clinically, this means a woman with pelvic pain may also report low back pain, groin pain, buttock pain, hip pain, pain with prolonged sitting, pain with walking, or discomfort during positional changes. These symptoms are not distractions from the pelvic pain story. They are often part of it.
The pelvis functions as a biomechanical crossroads. Loads from the trunk, spine, hips, and lower extremities are transferred through this region continuously. When movement becomes guarded, asymmetrical, or painful, the resulting compensation patterns can perpetuate symptoms.
Structures That Commonly Contribute to Musculoskeletal Pelvic Pain
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Pelvic floor muscles (levator ani): Can cause vaginal, rectal, perineal, or suprapubic pain; pain with sitting, sex, or voiding. This occurs due to protective guarding from visceral pain and poor relaxation after prolonged irritation.
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Obturator internus: Can refer deep pelvic, lateral vaginal, hip, or buttock pain. Shares fascial attachments with the pelvic floor and becomes tender when the hip and pelvis guard together.
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Abdominal wall: Can cause suprapubic and lower quadrant pain that mimics visceral pain. Trigger points often develop after surgery, bracing, or repeated inflammation.
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Hip rotators and adductors: Can cause groin, inner thigh, or anterior pelvis pain. Altered gait and sitting posture from pelvic pain lead to chronic overload.
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Lumbar spine / SI joint / pelvic girdle: Can refer low back, buttock, or posterior pelvis pain. Pain changes how loads transfer through this biomechanical crossroads.
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Pudendal and nearby nerves: Can cause burning or zinging in the perineum, vulva, or rectum, which worsens with sitting. Often driven by mechanosensitivity in a tight, inflamed myofascial environment, rather than true entrapment.
4. Myofascial Tissues Can Refer Pain in Misleading Ways
One reason musculoskeletal pelvic pain is missed is that myofascial pain does not always stay where it starts. Tender points in pelvic floor muscles or the abdominal wall can produce pain that feels vaginal, rectal, suprapubic, or even visceral.
This helps explain why some patients feel as though their bladder, bowel, vagina, vulva, or uterus is the primary source of pain, yet formal evaluation does not fully account for the intensity or distribution of symptoms. The nervous system does not map pain with perfect precision. When myofascial tissues are involved, pain patterns can be diffuse, overlapping, and difficult to localize.
5. Nerves Can Become Irritated in a Tight, Inflamed Environment
Muscles and fascia do not act in isolation. They share space with peripheral nerves. When the pelvic floor and surrounding soft tissues are tight, tender, and mechanically sensitive, nerves traveling through that environment may also become irritated.
This does not always mean a classic nerve entrapment syndrome. More commonly, it means increased neural mechanosensitivity. Nerves become less tolerant of pressure, stretch, and movement. Patients may describe burning, zinging, rawness, aching, or pain with sitting, penetration, or certain hip positions.
Again, this reinforces an important principle: chronic pelvic pain is often multimechanistic. A patient may simultaneously have visceral disease, pelvic floor overactivity, myofascial trigger points, biomechanical dysfunction, and neural sensitization.
6. The Pain System Itself Becomes More Reactive
Persistent pelvic pain is not only a problem of tissues; it is also a problem of pain processing. Over time, ongoing nociceptive input from pelvic organs and musculoskeletal structures can increase the sensitivity of the nervous system. This lowers the threshold for pain, broadens the area of pain, and makes otherwise minor stimuli feel severe.
In that setting, the pelvic floor may tighten more easily, muscles may fatigue more quickly, and pain may outlast the original trigger. This is one reason women with chronic pelvic pain often describe flares that seem disproportionate to a single event. The musculoskeletal system is not simply reacting to pain. It may now be participating in the ongoing maintenance of pain.
Symptom Patterns Suggesting a Musculoskeletal Contribution
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Pain with sitting: Often suggests pelvic floor overactivity, pudendal nerve irritation, or ischial/obturator tenderness.
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Deep pain with intercourse (dyspareunia): Implies levator ani and obturator internus tenderness; this can persist even after endometriosis is treated.
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Low back, hip, or groin pain alongside pelvic pain: Indicates regional musculoskeletal dysfunction, such as in the pelvic girdle, SI joint, or hip rotators.
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Burning, zinging, or rawness: Suggests increased neural mechanosensitivity in a tight myofascial environment.
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Pain during urination or defecation with normal workup: Often myofascial referral and pelvic floor non-relaxation rather than organ pathology alone.
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Flares that feel disproportionate to the trigger: Indicates central sensitization, where the pain system itself has become more reactive.
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Pain persisting after excision surgery or with reassuring imaging: A strong sign that musculoskeletal pain has taken on a life of its own and needs direct treatment.
7. Why This Matters for Diagnosis and Treatment
Recognizing musculoskeletal mechanisms changes the clinical approach. A normal ultrasound does not rule out pelvic pain. A visible endometriosis lesion does not automatically explain every symptom. And surgery alone may not resolve pain when pelvic floor dysfunction and myofascial pain are also present.
A more complete evaluation should consider pelvic floor tenderness and ability to relax, myofascial pain in the abdominal wall and deep hip muscles, lumbar, hip, and pelvic girdle dysfunction, pain with movement, sitting, intercourse, urination, or defecation, and signs of regional pain amplification or sensitization.
This is why multidisciplinary care is often necessary. For many women, the best outcomes come from treating both the underlying pelvic condition and the secondary musculoskeletal consequences of living with pain.
Different treatments target different links in the amplification cascade. Most patients benefit from a combination of tiers, adjusted over time.
Common Treatment Modalities and Who They Help
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Pelvic floor physical therapy: Targets muscle overactivity, coordination, trigger points, fascial mobility, breathing, and posture. Recommended first-line for nearly everyone with chronic pelvic pain alongside medical treatment.
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Manual trigger-point release: Targets discrete tender points in the pelvic floor, abdominal wall, or hip rotators. Helpful for patients with focal reproducible tenderness that reproduces their pain.
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Trigger-point injections (lidocaine ± steroid): Used for persistent tender points that do not respond to manual therapy alone. Best for patients who have plateaued with pelvic PT or cannot tolerate internal work.
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Pelvic floor botulinum toxin (Botox) injections: Treats severely overactive, non-relaxing pelvic floor muscles driving dyspareunia and myofascial pain. Ideal for patients with documented high-tone pelvic floor dysfunction who haven’t responded adequately to PT.
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Nerve blocks (e.g. pudendal): Addresses peripheral nerve-driven pain patterns. Used for patients with neuropathic features like burning, zinging, or pain with sitting.
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Centrally acting medications (e.g. tricyclics, SNRIs, gabapentinoids): Focuses on central sensitization and widespread pain amplification. Helpful for patients experiencing widespread tenderness, sleep disruption, and extreme flares.
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Hormonal suppression and/or excision surgery: Eradicates the underlying endometriosis driver of inflammation and visceral nociception. Indicated for patients with confirmed or suspected endometriosis, ideally paired with pelvic floor rehab.
The Bottom Line
Pelvic pain in women is not solely gynecologic, urologic, gastrointestinal, or psychological. It is frequently musculoskeletal as well.
The muscles, fascia, joints, and nerves of the pelvis can generate pain, refer pain, amplify pain, and maintain pain long after the original trigger has appeared. For women with endometriosis, this matters profoundly. Endometriosis may start the pain story, but the musculoskeletal system may help explain why the story continues — and why treating only the lesions is often not enough.
EXPERT ROUNDTABLE
A Conversation on Pelvic Pain, Pelvic PT, and Botox
Dr. Andrea Vidali, Dr. Sallie Sarrel, and Dr. Osbert Fernandez discuss the clinical realities of treating musculoskeletal pelvic pain in women with endometriosis.
The Panelists:
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Dr. Andrea Vidali: Gynecologic surgeon specializing in endometriosis excision.
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Dr. Sallie Sarrel: Pelvic floor physical therapist with a focus on chronic pelvic pain and postoperative rehabilitation.
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Dr. Osbert Fernandez: Gynecologic surgeon experienced with advanced pelvic surgery, trigger-point, and pelvic floor botulinum toxin injections.
Why do so many women still hurt after endometriosis surgery?
Dr. Andrea Vidali: “The lesions we see at surgery aren’t always the only thing driving the pain. If someone has had endometriosis for years, her pelvic floor and abdominal wall have been reacting the entire time. We can do a thorough excision, achieve pathology-confirmed clearance, and she can still walk out with dyspareunia, painful sitting, or bladder urgency because the muscles and nerves haven’t gotten the memo. Surgery is a necessary step for many patients, but it’s rarely the whole treatment. “
Dr. Sallie Sarrel: “I see this constantly. A patient comes in a few months postoperative, her surgeon did beautiful work, her imaging is reassuring — and her levator ani and obturator internus are hypertonic and exquisitely tender. Her diaphragm is locked up. She can’t eccentrically lengthen the pelvic floor on exhale. That’s not a surgical failure. That’s years of protective guarding that nobody has addressed yet. The tissue needs rehabilitation, just like a knee after ACL surgery. “
Dr. Osbert Fernandez: “And from the surgical side, we know that prolonged nociceptive input rewires the system. Peripheral sensitization at the tissue level, central sensitization at the cord and brain. At a certain point the pain system itself is the disease. You can remove every visible lesion and still have a sensitized pelvis. That’s the population that needs more than surgery. “
Where does pelvic floor physical therapy fit in?
Dr. Sallie Sarrel: “Ideally, pelvic PT is not the last resort — it’s embedded in the plan from the start. For a patient with suspected endometriosis and dyspareunia, I want to see her before surgery, not six months after. We work on down-training the pelvic floor, manual release of the levator ani and obturator internus, mobilization of the abdominal wall and hip fascia, breath work, and graded return to sex and movement. Postoperatively, we pick up again to prevent new protective patterns from setting in. “
Dr. Andrea Vidali: “I’ve changed how I counsel patients because of this. I now tell everyone who comes in for pelvic pain that surgery without pelvic floor rehab is like taking the thorn out but leaving the limp. If a patient has been in pain for years, I refer her to pelvic PT before we even schedule the operation. The outcomes are noticeably better. “
Dr. Osbert Fernandez: “Pelvic PT also stratifies who truly needs what we do interventionally. If a patient has done a real course of pelvic floor PT with an experienced therapist and she’s plateaued, that’s a different conversation than someone who has never had hands-on care. I want to see that first. “
When do you start thinking about Botox for the pelvic floor?
Dr. Osbert Fernandez: “Botulinum toxin is not a first-line treatment and shouldn’t be framed that way. But in the right patient it can be transformative. The candidate I look for has a clearly overactive, non-relaxing pelvic floor, significant myofascial tenderness, dyspareunia or painful sitting, and has done a meaningful course of pelvic floor PT without adequate relief. In that patient, injecting the levator ani and sometimes obturator internus can quiet the muscle enough to let PT actually progress. It’s a rehabilitation tool, not a fix. “
Dr. Sallie Sarrel: “That framing matters. I tell my patients: Botox opens a window. It doesn’t replace the work. If we don’t retrain the muscle during that quieter period — coordination, relaxation, motor control, graded exposure — the old pattern just returns when the effect wears off. The Botox patients who do best are the ones who come straight back into therapy while the muscle is finally cooperative. “
Dr. Andrea Vidali: “I’ve started combining Botox with surgery in carefully selected patients. If I’m operating on someone with severe endometriosis and documented high-tone pelvic floor dysfunction, we’ll sometimes inject the pelvic floor at the same anesthetic. It can smooth the postoperative course considerably — less guarding, easier return to pelvic PT, lower narcotic requirement. It has to be the right patient, though. Not everyone benefits. “
What about trigger-point injections, nerve blocks, and medications?
Dr. Osbert Fernandez: “Trigger-point injections — lidocaine, sometimes with a small amount of steroid — are useful for discrete, reproducible tender points in the abdominal wall or pelvic floor that haven’t responded to manual therapy. Pudendal nerve blocks are mostly diagnostic: they tell us whether pudendal irritation is contributing. For central features — widespread pain, sleep disruption, allodynia — we add a centrally acting medication. A low-dose tricyclic or an SNRI can take the edge off the sensitization enough for rehab to work. “
Dr. Sallie Sarrel: “I work closely with the surgical and pain management teams because interventions and PT are synergistic. If a patient can’t tolerate internal work because a trigger point is too irritable, an injection can make the next PT visit productive. Conversely, if her nervous system is too sensitized to benefit from hands-on work at all, she probably needs the central piece addressed first. “
What is the single most important message for patients?
Dr. Andrea Vidali: “You are not imagining it, and you are not failing treatment. If your pain persists after surgery or medical management, that is a known pattern with known mechanisms. Your pelvic floor and your pain system are part of the picture. That’s good news, because it means there are more levers to pull. “
Dr. Sallie Sarrel: “Find a pelvic floor physical therapist. Not a general PT — someone who does internal work and understands chronic pelvic pain. That single referral changes trajectories. And bring your partner or support person to at least one visit; they need to understand what you’re navigating. “
Dr. Osbert Fernandez: “Multidisciplinary care is not a luxury in chronic pelvic pain — it is the standard. A gynecologist, a pelvic floor physical therapist, and a pain specialist working together will almost always outperform any one of us working alone. Patients shouldn’t have to assemble that team themselves, but when they do, the outcomes get dramatically better. The best outcomes in chronic pelvic pain come not from choosing between surgery, pelvic PT, and interventional care — but from sequencing them intelligently around the individual patient. “
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