Sciatic hernia causing sciatica: MRI and MR neurography showing entrapment of sciatic nerve

Sciatic foramen anatomy and common pathologies: a pictorial review

This article reviews the relevant anatomy, imaging features on computed tomography, magnetic resonance imaging, and management of common processes involving the sciatic foramen. The anatomy of the sciatic foramen is complex and provides an important conduit between the pelvis, gluteus, and lower extremity. This paper reviewed the anatomy, common pathologies, and imaging features of this region including trauma, infection, nerve entrapment, tumor spread, hernia, and vascular anomaly.

Bilateral sciatic hernias in an elderly woman successfully managed with robotic surgery: A case report and literature review

Introduction

Sciatic hernias are the rarest form of pelvic floor hernias as well as an uncommon cause of sciatica. A high index of suspicion is required to make the diagnosis due to its variable clinical presentation. This is the first case describing bilateral intestinal sciatic hernia, diagnosis, and robotic surgical repair.

Presentation of case

A 77-year-old female with history of chronic back pain and diverticulitis presented with three weeks of abdominal pain, radiating down her legs bilaterally. Computed tomography (CT) revealed bilateral sciatic notch hernias without evidence of bowel obstruction. Magnetic resonance imaging (MRI) confirmed compression of the sciatic nerves within the sciatic notch bilaterally. She underwent robotic bilateral retroperitoneal sciatic notch hernia repair successfully.

Discussion

There are several independent causes of abdominal pain and bilateral radiating leg pain. Sciatic hernias are an unusual cause of both. Aside from bowel, the hernia can involve other structures, such as the bladder, ureters, or ovaries, potentially creating drastically different clinical pictures. Laparoscopic or robotic repair have been proven superior to open surgery in the literature.

Conclusion

This case demonstrates that bilateral sciatic hernias can present as uncomplicated sciatica in an elderly patient, but the addition of seemingly unrelated abdominal pain should warrant further investigation. Minimally invasive robotic repair can successfully treat sciatic hernias.

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Sciatic hernias are the rare pelvic floor hernias with variable presentations.

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First case of diagnosis and surgical repair of bilateral sciatic hernias

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Minimally-invasive robotic repair can successfully treat sciatic hernias.

Magnetic Resonance Neurography for Evaluation of Peripheral Nerves

Peripheral nerve injuries (PNIs) continue to present both diagnostic and treatment challenges. While nerve transections are typically a straightforward diagnosis, other types of PNIs, such as chronic or traumatic nerve compression, may be more difficult to evaluate due to their varied presentation and limitations of current diagnostic tools. As a result, diagnosis may be delayed, and these patients may go on to develop progressive symptoms, impeding normal activity. In the past, PNIs were diagnosed by history and clinical examination alone or techniques that raised concerns regarding accuracy, invasiveness, or operator dependency. Magnetic resonance neurography (MRN) has been increasingly utilized in clinical settings due to its ability to visualize complex nerve structures along their entire pathway and distinguish nerves from surrounding vasculature and tissue in a noninvasive manner. In this review, we discuss the clinical applications of MRN in the diagnosis, as well as pre- and postsurgical assessments of patients with peripheral neuropathies.

Gluteal liposarcoma presenting as sciatic hernia: A case report and review of literature

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Sciatic hernias are very rare.

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Lipomatous tumors herniating through the sciatic foramen have only been documented in 6 cases.

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CT and MRI imaging of the abdomen and pelvis facilitate diagnosis and appropriate surgical treatment.

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Documented findings add to the current literature and will guide appropriate treatment in future cases.

Introduction

Lipomatous tumors herniating through the sciatic foramen are extremely rare with less than 6 cases reported in the existing literature. We report a case of gluteal well differentiated liposarcoma that presented as sciatic hernia.

Presentation of case

A 66-year-old female presented with persistent pain in the right gluteal region. Physical examination coupled with CT/MRI scans identified a firm mass extending into the right pelvic side via the sciatic foramen. It measured approximately 18.9 cm × 13 cm × 22.8 cm. The tumor was resected via transgluteal approach. Immunohistochemical and microscopic features were consistent with well-differentiated liposarcoma.

Discussion

Although sciatic hernias associated with intraabdominal contents have been recorded less than 100 times in the literature, instances where gluteal lipomatous tumors manifest as sciatic hernias are even more rare. In this case the gluteal liposarcoma was successfully identified utilizing CT/MRI scanning followed by a transgluteal excision of the mass.

Conclusion

While sciatic hernias are rare, lipomatous/liposarcomatous tumors presenting as sciatic hernias are extremely rare. This case report highlights a combination of rare phenomena. The information presented adds to the current evidence that will guide accurate diagnosis and appropriate treatment of future cases.

The tip of the iceberg: lipomatous tumours presenting as abdominal or pelvic wall hernias

Liposarcomas are the most common soft tissue sarcoma. They occur mainly in the thigh or retroperitoneum. Due to their size, lipomatous tumours can herniate either through the abdominal wall or in the groin. The part of the tumour that herniates represents only the ‘tip of the iceberg’, as the main part of the tumour is not detectable clinically and is often underestimated. Due to their deep location, lipomatous tumours are often large at the time of presentation and therefore their surgical management can be challenging. Furthermore, due to their delayed presentation, there is a higher risk of de-differentiation. In this pictorial review, we discuss different presentations of herniating lipomatous tumours according to the location of the abdominal wall defects. We aim to cover a wide spectrum of hernia defects including inguinal, ventral, lumbar, sciatic and ischiorectal hernias. We also present cases of tumours within the psoas compartment ‘herniating’ from the pelvis into the thigh. In case of a palpable lump, the first diagnostic step is to perform an ultrasound. If the herniating tissue is not fully accessible with ultrasound, additional cross-sectional imaging by CT or MRI is warranted. In this article, CT and MRI findings in lipomatous tumours are addressed and the use of contrast enhanced sequences in MRI is discussed. Patients’ outcome depends not only on adequate diagnosis but also on the correct route of tissue sampling for histology and oncological resection to prevent local recurrence and loss of function. Therefore, referral to a specialised sarcoma treatment centre is key and needs to be done before biopsy.

Successful manual reduction for ureterosciatic hernia: A case report

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Manual reduction was successfully performed for a patient with sciatic hernia.

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There were no report of closed manual reduction previously.

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A sciatic hernia in women may be manually reduced without surgery.

Introduction

Sciatic hernias are the least common type of pelvic floor hernias. The purpose of this study was to present a novel technique for manual reduction and to conduct a systematic review of previous reports of sciatic hernias to characterize them and review the outcomes.

Presentation of case

An 86-year-old female presented with left-sided lumbar pain. She had a past medical history of rheumatoid arthritis and was treated with prednisolone and methotrexate. Her left abdomen and left lumbar area were tender. An unenhanced abdominal computed tomography scan revealed invagination of the left ureter into the left sciatic foramen and a dilated left proximal ureter and renal pelvis. Ultrasonography showed an invaginated left ureter viewing from the left buttock. She was diagnosed with a sciatic hernia. Ultrasound-guided manual transvaginal reduction was performed. Post-procedure unenhanced abdominal computed tomography scan confirmed reduction of the ureter. After 10-months of follow-up, there is no evidence of recurrence.

Discussion

Previous reports of patients with sciatic hernia were identified. Clinical data associated with the hernia, reduction technique and clinical outcomes were collected for 72 patients. Open reduction was performed in 24 patients. A ureteral stent was placed in eight patients when the hernia contained the ureter. Four postoperative complications including one death were reported in adults. There were no reports of closed manual reduction.

Conclusion

A sciatic hernia in women may be manually reduced without surgery. Further reviews of this rare entity are needed to determine the best management strategy.

Giant gluteal lipoma presenting as a sciatic hernia

BACKGROUND

Sciatic hernia is considered to be the rarest hernia of pelvic floor with less than one hundred reports published worldwide. Lipoma in the hernia sac is even more unique pathology with only few cases reported in the literature. We report a case of gluteal lipoma protruding into pelvis, displacing rectum with bladder and presenting as a sciatic hernia.

CASE PRESENTATION

A 53-year-old male presented with an expanding, slightly reducible, right gluteal painful mass, back pain, dull pressure in lower abdomen and perianal region radiating to the right buttock, urgent urination and defecation. Lower back pain lasts for more than 7 years, other symptoms—6 months. No spinal pathology was found on X-ray. On examination patient seemed well nourished, BMI 29, abdomen was soft, without palpable masses or signs of peritonitis. Digital rectal examination showed no pathology. There was a reducible lump on the lateral side of right gluteus. Computer tomography (CT scan) demonstrated a large intra- and extra-pelvic fatty mass traversing the greater sciatic foramen. The tumor was surgically removed through lower middle laparotomy approach. Subsequent pathological examination revealed lipoma. The patient recovered uneventfully, was discharged 8 days later. MRI scan was advised following 1 year after the surgery.

CONCLUSION

The presence of a gluteal mass should always suggest the possibility of a sciatic hernia.

Choice of imaging modality in the diagnosis of sciatic hernia

Sciatic hernias are one of the rarest types of hernia and often pose diagnostic difficulty to clinicians. We report a case of an 80-year-old lady with a sciatic hernia who had a falsely negative computed tomography (CT) but was found to have a colonic hernia on ultrasonography. The authors recommend that for patients in which there is a high degree of clinical suspicion for a sciatic hernia and a negative CT, ultrasonography may be considered as a useful imaging modality to confirm the diagnosis.

Giant gluteal lipoma presenting as a sciatic hernia

BACKGROUND

Sciatic hernia is considered to be the rarest hernia of pelvic floor with less than one hundred reports published worldwide. Lipoma in the hernia sac is even more unique pathology with only few cases reported in the literature. We report a case of gluteal lipoma protruding into pelvis, displacing rectum with bladder and presenting as a sciatic hernia.

CASE PRESENTATION

A 53-year-old male presented with an expanding, slightly reducible, right gluteal painful mass, back pain, dull pressure in lower abdomen and perianal region radiating to the right buttock, urgent urination and defecation. Lower back pain lasts for more than 7 years, other symptoms-6 months. No spinal pathology was found on X-ray. On examination patient seemed well nourished, BMI 29, abdomen was soft, without palpable masses or signs of peritonitis. Digital rectal examination showed no pathology. There was a reducible lump on the lateral side of right gluteus. Computer tomography (CT scan) demonstrated a large intra- and extra-pelvic fatty mass traversing the greater sciatic foramen. The tumor was surgically removed through lower middle laparotomy approach. Subsequent pathological examination revealed lipoma. The patient recovered uneventfully, was discharged 8 days later. MRI scan was advised following 1 year after the surgery.

CONCLUSION

The presence of a gluteal mass should always suggest the possibility of a sciatic hernia.

3-T high-resolution MR neurography of sciatic neuropathy

OBJECTIVE

The sciatic nerve may normally exhibit mild T2 hyperintensity in MR neurography (MRN) images, rendering assessment of sciatic neuropathy difficult. The purpose of this case-control study was to evaluate whether a quantitative and qualitative analysis of the sciatic nerves and regional skeletal muscles increases the accuracy of MRN in detecting sciatic neuropathy.

MATERIALS AND METHODS

We retrospectively reviewed the MRN studies of the pelvis and thighs of 34 subjects (12 men and 22 women; mean [± SD] age, 50 ± 15 years), of which 17 had a final diagnosis of sciatic neuropathy according to electrodiagnostic or surgical confirmation, and 17 had no evidence of sciatic neuropathy and served as control subjects. On each side, the sciatic nerves were evaluated for signal intensity (SI), size, course, and fascicular shape, whereas the regional skeletal muscles were evaluated for edema, fatty replacement, and atrophy. In addition, the nerve-to-vessel SI ratio was registered for each side at the same time and 8 months later.

RESULTS

The sciatic nerves of the abnormal sides exhibited higher nerve-to-vessel SI ratios and higher incidences of T2 hyperintensity, enlargement, and abnormal fascicular shape compared to the nerves of the normal sides. The regional muscles of the abnormal sides demonstrated a higher grade of fatty infiltration and higher frequencies of edema and atrophy. A cutoff value of nerve-to-vessel SI ratio of 0.89 exhibited high sensitivity and specificity in predicting sciatic neuropathy. Calculation of the nerve-to-vessel SI ratio demonstrated excellent inter- and intraobserver reliability.

CONCLUSION

Both qualitative and quantitative criteria should be used to suggest the MRN diagnosis of sciatic neuropathy.