It may be associated with neurological dysfunction, such as weakness and numbness. Causes
Risk factors
Modifiable risk factors for sciatica include smoking, obesity, occupation, and physical sports where back muscles and heavy weights are involved. Non-modifiable risk factors include increasing age, being male, and having a personal history of low back pain. Spinal disc herniation
Spinal disc herniation pressing on one of the lumbar or sacral nerve roots is the most frequent cause of sciatica, being present in about 90% of cases. This is particularly true in those under age 50. Disc herniation most often occurs during heavy lifting. Pain typically increases when bending forward or sitting, and reduces when lying down or walking. Spinal stenosis
Other compressive spinal causes include lumbar spinal stenosis, a condition in which the spinal canal, the space the spinal cord runs through, narrows and compresses the spinal cord, cauda equina, or sciatic nerve roots. This narrowing can be caused by bone spurs, spondylolisthesis, inflammation, or a herniated disc, which decreases available space for the spinal cord, thus pinching and irritating nerves from the spinal cord that become the sciatic nerve. This is the most frequent cause after age 50. Sciatic pain due to spinal stenosis is most commonly brought on by standing, walking, or sitting for extended periods of time, and reduces when bending forward. However, pain can arise with any position or activity in severe cases. The pain is most commonly relieved by rest.
Aggressive fibromatosis or desmoid tumor is a rare condition. Desmoid tumors arise from cells called fibroblasts, which are found throughout the body and provide structural support, protection to the vital organs, and play a critical role in wound healing. These tumors tend to occur in women in their thirties, but can occur in anyone at any age. They can be either relatively slow-growing or malignant. However, aggressive fibromatosis is locally aggressive and can cause life-threatening problems or even death when they compress vital organs such as intestines, kidneys, lungs, blood vessels, or nerves. Most cases are sporadic, but some are associated with familial adenomatous polyposis (FAP). Approximately 10% of individuals with Gardners syndrome, a type of FAP with extracolonic features, have desmoid tumors.The World Health Organization reclassified desmoid tumors (termed desmoid-type fibromatosis) as a specific type of tumor in the category of intermediate (locally aggressive) fibroblastic and myofibroblastic tumors.Histologically they resemble very low-grade fibrosarcomas, but they are very locally aggressive and tend to recur even after complete resection. There is a tendency for recurrence in the setting of prior surgery; in one study, two-thirds of patients with desmoid tumors had a history of prior abdominal surgery. Risk factor
Risk factors for desmoid disease amongst FAP patients include female sex, a 3 APC mutation, a positive family history, and a history of previous abdominal surgery. Diagnosis
Classification
Desmoid tumors may be classified as extra-abdominal, abdominal wall, or intra-abdominal (the last is more common in patients with FAP).