Surgical treatment of lipomas of conus medullaris

Objective To study the pathological changes of lipomas of conus medullaris and the appropriate surgical treatment for removing such lipomas for optimal reconstruction of normal spinal cord anatomy.Methods The clinical data of 73 patients ( aged from 1.5 months to 18 years) who underwent surgical removal of lipoma of conus medullaris from January 2005 to July 2009 were collected.The neurological symptoms included pain, urine and stool incontinence, and bilateral lower limb dysfunction.The surgical procedures consisted of excision of subcutaneous and intradural extramedullary lipoma, partial excision of intramedullary lipoma, detachment of the spinal cord from the dural membrane, relief of tethered spinal cord, and excision of the affected filum terminale.Results The main pathological changes in patients with lipoma of the conus medullaris were ventral deviation of the spinal cord caused by compression from dorsal lipoma, traction on the spinal cord from attachment of intradural lipoma and subcutaneous lipoma, increased tight fit between the spinal cord and the dural membrane on both sides, and degeneration of the filum terminale.Sixty - seven patients were followed - up from 1 to 5 years.The improvement after surgery varied among the symptomatic patients.Five patients had transient deterioration of symptoms after surgery.All asymptomatic patients remained asymptomatic.Conclusion Only through thorough understanding of the pathology of lipoma of conus medullaris, we could optimally excise the lipoma, untether the spinal cord, reconstruct the normal anatomy of the spinal cord and rehabilitate neurological function. Key words: Tethered spinal cord;  Lipoma;  Pathology;  Surgery