Cyclic sciatica related to an extrapelvic endometriosis of the sciatic nerve: new concepts in surgical therapy

Entrapped by pain: The diagnosis and management of endometriosis affecting somatic nerves

Somatic nerve entrapment caused by endometriosis is an underrecognized and often misdiagnosed issue that leads to many women suffering unnecessarily. While the classic symptoms of endometriosis are well-known to the gynaecologic surgeon, the dermatomal-type pain caused by endometriosis impacting neural structures is not within gynecologic day-to-day practice, which often complicates diagnosis and delays treatment. A thorough understanding of pelvic neuroanatomy and a neuropelveologic approach is required for accurate assessments of patients with endometriosis and nerve entrapment. Magnetic resonance imaging is the preferred imaging modality for this presentation of endometriosis. Surgical management with laparoscopic or robotic-assisted techniques is the preferred approach to treatment, with excellent long-term results reported after nerve detrapment and endometriosis excision. The review calls for increased awareness and education on the links between endometriosis and the nervous system, advocating for patient-centered care and further research to refine the diagnosis and treatment of this challenging condition.

Sciatic endometriosis: A narrative review of an unusual neurogynecologic condition

Endometriosis is a condition in which there is an ectopic growth of endometrial tissue. Sciatic endometriosis, otherwise known as catamenial sciatica, is a rare but exceedingly significant presentation of endometriosis. Symptoms include cyclic sciatic pain that peaks during the menstrual period; additionally, paresthesia, paresis, and areflexia may occur with this condition. Sciatic endometriosis can be presumptively diagnosed in response to empiric treatment (e.g. gonadotropin-releasing hormone analogs) or imaging studies, but a definitive diagnosis of sciatic endometriosis may occur from examining tissue obtained during surgery. Surgical removal of endometriosis from the sciatic nerve root can potentially eliminate symptoms while maintaining normal reproductive function, though poses particular surgical risks. Familiarity with this rare condition is paramount to making this diagnosis and the initiation of earlier treatment.

What abdominal radiologists should know about extragenital endometriosis-associated neuropathy

PURPOSE

The aim of this study is to provide an overview of endometriosis-associated neuropathy and to review main anatomical concepts of intrapelvic peripheral nerves.

METHODS

In this pictorial essay, we review the anatomy of pelvic nerves and imaging features of endometriosis-associated neuropathy. We also evaluate clinical findings, imaging features, and outcome of seven patients with endometriosis-associated neuropathy.

RESULTS

Nerve involvement by endometriosis is rare and may manifest with neurological symptoms, including pain, muscle weakness, bowel and bladder incontinence, and paraplegia. The neural involvement may be isolated or caused by a direct extension of a deep infiltrating endometriosis of the pelvic structure. Magnetic resonance imaging (MRI) is a reliable imaging modality for detecting neural involvement of endometriosis. On MRI, the main imaging features are retractile fibrous tissue and endometriomas. The signal intensity of the endometriotic tissue may vary depending on the age of the hemorrhage and the proportion of endometrial cells and stroma. Early diagnosis and treatment may avoid permanent neural damage.

CONCLUSION

Considering that patients with endometriosis usually undergo pelvic MRI, which is generally reported by a non-musculoskeletal-trained radiologist, abdominal radiologists need to be familiar with the pelvic nerve anatomy and the possible patterns of presentation of neural endometriosis. Early diagnosis may obviate permanent nerve damage and MRI is a reliable tool for the diagnosis.

Extrapelvic Sciatic Nerve Endometriosis, the Role of Magnetic Resonance Imaging: Case Report and Systematic Review

Endometriosis (EN) is a common gynecological condition characterized by the presence of functional endometrium located outside the uterine cavity. Sciatic nerve (SN) is rarely affected by EN. Magnetic resonance imaging allows a direct visualization of the spinal and SN, and it is the modality of choice for the study of SN involvement in extrapelvic EN. We report a case of an endometrioma located in the right SN with a systematic review of the literature.

MR imaging of endometriosis: Spectrum of disease

Endometriosis is a common gynecological disorder defined by the presence of endometrial tissue outside the uterus. It is the most common cause of chronic pelvic pain and typically affects the ovaries, uterine ligaments, peritoneum, tubes, rectovaginal septum and bladder. It may, however, be found at various extrapelvic sites, including the perineum, liver, pancreas, lung or even the central nervous system, and in such cases, diagnosis may be quite challenging. Even though definitive diagnosis requires laparoscopy, preoperative identification of endometriosis is important not only to differentiate it from other diseases with similar clinical presentations but also, for accurate presurgical mapping, since complete removal of all endometriotic foci is critical for the effective treatment of the patient's symptoms. Ultrasound is performed initially, but magnetic resonance imaging (MRI) is increasingly being used, particularly when sonographic findings are unclear, when deep pelvic endometriosis is suspected or when surgery is planned, as it provides better contrast resolution and a larger field of view compared to ultrasound. In this article, we will discuss distinctive MRI appearances of endometriotic foci and we will review common and uncommon locations of endometriosis within the body, in an attempt to familiarize radiologists with its wide spectrum of manifestations.

Sciatic endometriosis induces mechanical hypersensitivity, segmental nerve damage, and robust local inflammation in rats

BACKGROUND

Endometriosis is a common cause of pain including radicular pain. Ectopic endometrial tissue may directly affect peripheral nerves including the sciatic, which has not been modelled in animals.

METHODS

We developed a rat model for sciatic endometriosis by grafting a piece of autologous uterine tissue around the sciatic nerve. Control animals underwent a similar surgery but received a graft of pelvic fat tissue.

RESULTS

The uterine grafts survived and developed fluid-filled cysts; the adjacent nerve showed signs of swelling and damage. Mechanical and cold hypersensitivity and allodynia of the ipsilateral hindpaw developed gradually over the first 2 weeks after the surgery, peaked at 2-5 weeks, and was almost resolved by 7 weeks. Control animals showed only minor changes in these pain behaviours. Histological signs of inflammation in the uterine graft and in the adjacent nerve were observed at 3 weeks but were resolving by 7 weeks. In vivo fibre recording showed increased spontaneous activity, especially of C-fibres, in sciatic nerve proximal to the uterine graft. Several pro-inflammatory cytokines including interluekin-18, VEGF, fractalkine, and MIP-1α, were elevated in the uterine graft plus sciatic nerve samples, compared to samples from normal nerve or nerve plus fat graft. Growth associated protein 43 (GAP43), a marker of regenerating nerve fibres, was observed in the adjacent sciatic nerve as well as in the uterine graft.

CONCLUSIONS

This model shared many features with other rat models of endometriosis, but also had some unique features more closely related to neuropathic pain models.

WHAT DOES THIS STUDY/REVIEW ADD

Some especially painful forms of endometriosis are essentially neuropathic, because peripheral nerves are directly affected by nearby ectopic endometrial tissue. We modelled endometriosis by implanting autologous uterine tissue around rat sciatic nerve. We observed mechanical and cold pain behaviours along with signs of inflammation and nerve damage and increased pro-inflammatory cytokines at the implant site. Pain behaviours correlated with signs of nerve inflammation and damage rather than with cyst survival.

Magnetic resonance imaging evidence for perineural spread of endometriosis to the lumbosacral plexus: report of 2 cases

Sciatic nerve endometriosis (EM) is a rare presentation of retroperitoneal EM. The authors present 2 cases of catamenial sciatica diagnosed as sciatic nerve EM. They propose that both cases can be explained by perineural spread of EM from the uterus to the sacral plexus along the pelvic autonomie nerves and then further distally to the sciatic nerve or proximally to the spinal nerves. This explanation is supported by MRI evidence in both cases. As a proof of concept, the authors retrieved and analyzed the original MRI studies of a case reported in the literature and found a similar pattern of spread. They believe that the imaging evidence of their institutional cases together with the outside case is a very compelling indication for perineural spread as a mechanism of EM of the nerve.

Distribution pattern of surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs in males

Background:

The pattern of distribution of surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs has been published, though scantily, especially in males. We decided to look at our own series, compare and contrast ours with some of those published.

Materials and Methods:

We treated 88 locations of this lesion in 68 males. The clinical features were those of lower back pains, with or without radiation into the lower extremities, sensory loss and paresis of the limbs. There was a case of loss of urinary bladder and ano-rectal control. All lesions were confirmed through cauda-equinograms and treated under general anaesthesia in knee-chest position (MECCA position). The patients were followed up for 3-6 months post-operatively.

Results:

There were 88 locations in 68 males of 21-70 years of age, with 29 prolapses occurring during the age range 31-40 years, while 54 locations were on the left and 48 at L4/5. The procedures were well tolerated by all patients and there were no post-operative complications.

Conclusion:

This lesion in our series occurred mostly on the left, at the L4/5 level and peaked at 31-40 years age range. The predictability of occurrence of this disease, using side, level and age is still not feasible in males from our series.

Surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs in females: a comparative study of incidence and causative factors and treatment

Background and Objective:

There are various postulated possible causes of surgically symptomatic prolapsed intervertebral discs in the lumbar and sacral regions. They may be acting singularly or collectively. Yet, these factors, which could vary in different environments, have not been satisfactorily confirmed. The intention of this study is to share the experience of the author in the occurrence, possible causative factors, and treatment of surgically symptomatic prolapsed lumbar and sacral intervertebral discs in females, and to compare this experience in Switzerland, Nigeria, and Jamaica using surgery records for a period of over 39 years.

Materials and Methods:

Records of these cases were examined and analyzed with the intent of comparing the frequency of occurrence and possible causative factors of this lesion in some countries.

Results:

There were 60 locations in 51 patients in Basel (Caucasian population only), 4 locations in 1 patient in Imo and Ebonyi States (African population only), and none in Jamaica (mixed population). The patients’ ages ranged from 19 to 71 years in Switzerland, and the only patient in Nigeria was 49 years old.

Conclusion:

The study revealed that surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs in females occurred more in Basel, Switzerland, than in Imo and Ebonyi States of Nigeria and none occurred in Jamaica, West Indies. Racial differences, certain sporting/recreational activities, smoking, and type of profession could have contributed to the development of this disease.

A pilot study of the prevalence of leg pain among women with endometriosis

Radiating leg pain is a common symptom presenting in manual therapy practices. Although this symptom has been reported as a complication of endometriosis, its prevalence and characteristics have not been studied. We surveyed members of a national endometriosis support group with endometriosis using a self-administered, mailed questionnaire. The main outcome measures were the prevalence and characteristics of leg pain. Of 94 respondents, leg pain was reported by 48 women (51%), and was bilateral in 59% of these symptomatic women. The likelihood of experiencing leg pain was related to weight gain since age 18, age, and height. The most common treatments tried included exercise, over-the-counter medications, and massage therapy, all with variable results. These data support leg pain as a prevalent complication of endometriosis, and that the disease may affect multiple peripheral nerves. Manual therapists should remain aware to this possible etiology for radiating pain.

Cyclic sciatica from extrapelvic endometriosis affecting the sciatic nerve

Sciatic (catamenial) radiculopathy, waxing and waning with the menstrual cycle, is an uncommon condition typically caused by pelvic endometriosis affecting the lumbosacral plexus or proximal sciatic nerve. The authors describe a woman with catamenial sciatica caused by endometriosis affecting the sciatic nerve trunk in the upper thigh. Symptomatic with leg pain for 5 years, this patient developed gluteal atrophy and sensory loss and decreased strength in the L-5 dermatomyotome, a distribution confirmed by electromyography. Magnetic resonance imaging suggested thickening of the sciatic nerve at and distal to the sciatic notch. At operation the nerve showed extrinsic and intrinsic abnormality, proven to be endometriosis. Her symptoms improved, and she began gonadotropin-releasing hormone agonist therapy for further suppression. This very unusual case shows that endometriosis can affect the sciatic nerve over a range of territory inside and outside the pelvis, and that surgery must be appropriately directed to avoid negative exploration. Surgical decompression achieves good relief of symptoms, and medical therapy also allows sustained suppression of this disease.

Endometriosis causing lower extremity deep vein thrombosis - case report and review of the literature

Endometriosis is a medical condition in women wherein endometrial cells deposited in the area outside the uterine cavity are influenced by hormonal changes, and produce symptoms depending on the site of implantation. A unique case of retroperitoneal endometriosis causing deep vein thrombosis from extrinsic compression of the right iliac vein is described. Clinical presentation with cyclical leg swelling, coincidental with menstruation and culminating with deep vein thrombosis, although very suggestive, has not been previously reported.

Post-traumatic catamenial sciatica

This article presents a unique case of posttraumatic extrapelvic endometriosis presenting as a gluteal mass causing cyclic sciatica. A 38-year-old woman presented with an enlarging right buttock mass over the previous 6 years. She also had symptoms of radicular pain referred to the right leg and foot with sitting and daily activity. Four years prior to noticing the mass, she sustained a gunshot wound through the lower abdomen while 5 months pregnant. Excisional biopsy of the gluteal mass revealed endometrioma. Sciatica is a common and painful disorder that is believed to have an incidence of 40% in the adult population. Sciatica is most often due to intraspinal pathology affecting the lumbar nerve roots. There are many recognized extraspinal etiologies for sciatica in the literature including aneurysms, sciatic hernia, abcess, neoplasm, trochanteric wire, piriformis syndrome, ischial fracture, a posteriorly flexed uterus, and even an intrauterine device following uterine perforation. Similarly, endometriosis is a gynecologic condition that represents a significant health problem for women of reproductive age as it occurs in up to 50% of premenopausal women and 71% to 87% in women with chronic pelvic pain. Although rare, endometriosis has a well known ability to migrate outside of the abdominal cavity and proliferate ectopically under the control of systemic estrogen.

Sciatica: a review of history, epidemiology, pathogenesis, and the role of epidural steroid injection in management

Radicular pain in the distribution of the sciatic nerve, resulting from herniation of one or more lumbar intervertebral discs, is a frequent and often debilitating event. The lifetime incidence of this condition is estimated to be between 13% and 40%. Fortunately, the majority of cases resolve spontaneously with simple analgesia and physiotherapy. However, the condition has the potential to become chronic and intractable, with major socio-economic implications. This review discusses the history, epidemiology, pathophysiology, and natural history of sciatica. A Medline search was performed to obtain the published literature on the sciatica, between 1966 and 2006. Hand searches of relevant journals were also performed. Epidemiological factors found to influence incidence of sciatica included increasing height, age, genetic predisposition, walking, jogging (if a previous history of sciatica), and particular physical occupations, including driving. The influence of herniated nucleus pulposus and the probable cytokine-mediated inflammatory response in lumbar and sacral nerve roots is discussed. An abnormal immune response and possible mechanical factors are also proposed as factors that may mediate pain. The ongoing issue of the role of epidural steroid injection in the treatment of this condition is also discussed, as well as potential hazards of this procedure and the direction that future research should take.

Sciatica in the female patient: anatomical considerations, aetiology and review of the literature

The principal author was confronted few years ago with the case of a 38-year-old woman with a 5-month history of ill-defined L5 sciatic pain that was referred to an orthopaedic department for investigation and eventual surgical treatment for what was suspected to be herniated disc-related sciatica. Removal of her enlarged uterus found unexpectedly close to the sacroiliac joint upon lumbar MRI abolished her symptoms. Review of the literature showed that the lumbosacral trunk is vulnerable to pressure from any abdominal mass originating from the uterus and the ovaries. Physiological processes in the female patient and gynaecological diseases may be the source of sciatica, often not readily searched for, leading to fruitless investigations and surgical treatments. The aim of the paper is to highlight gynaecological and obstetrical causes of sciatica and sciatica-like symptoms. To prevent unproductive expenses and morbidity, a thorough gynaecological examination should be done even though neurological examination may be suggestive of a herniated intervertebral disc, and the cyclic pattern of pain related to menses should be routinely asked for.

Laparoscopic neurolysis of the pelvic sciatic nerve in a case of catamenial footdrop

Isolated cases of cyclic sciatica associated with endometriosis have been reported since the 1940s. Surgical intervention, either by laparoscopy for lesions within the pelvis or by open procedures for extrapelvic lesions, has usually been performed. A 37-year-old woman with catamenial footdrop and pain of the right thigh came to our observation. Previously, she underwent laparoscopy for bilateral ovarian endometriomas. In a second laparoscopy, we removed her uterosacral right ligament and recto-vaginal endometriotic nodules. After a temporary improvement, a third surgical procedure was necessary: laparoscopic neurolysis to free the sciatic nerve from fibrotic tissue. Then the patient was treated with gonadotropin-releasing hormone analogs for 6 months, and she is free of symptoms 2 years after last surgery. This is the first described case of laparoscopic neurolysis of the proximal sciatic nerve. The procedure has been successful in treating a patient with endometriosis in whom the cause of the syndrome was probably due to entrapment of the nerve in fibrous tissue.

Nonneoplastic peripheral nerve tumors

Most of the nonneoplastic tumor-like lesions affecting the peripheral nervous system are rarely encountered. In many situations, a good history of the presenting symptoms can suggest a reactive or infectious neuroma. The physical examination can also suggest an inflammatory or hyperplastic lesion. In some cases, however, the correct diagnosis can only be made at surgery. Nonetheless, awareness of these lesions is important in limiting unnecessarily aggressive surgical procedures. Patients suspected of having nonneoplastic lesions are followed and treated surgically for symptomatic relief or when the diagnosis is unclear. In some situations, the surgical treatment of choice may be debated. Nevertheless, we adopt a conservative approach to these lesions and reserve more aggressive techniques for cases that do not respond to more conservative means.

Cyclic sciatica caused by infiltrative endometriosis: MRI findings

Endometriosis, an important gynecological disorder of reproductive women, affects most commonly the ovaries and less frequently the gastrointestinal tract, chest, urinary tract, and soft tissues. Endometriosis classically appears on MRI as a mass with a large cystic component and variable signal intensities on T1- and T2-weighted images due to the presence of variable degradation of hemorrhagic products. Endometriosis in an atypical location, an infiltrative appearance and without cystic-hemorrhagic components has rarely been described. We report on a 33-year-old woman with cyclic sciatica due to histologically documented infiltrative endometriosis involving the area of the left sciatic notch.