Surgical outcomes in thoracolumbar fractures with pure conus medullaris syndrome

Pure conus medullaris syndrome is defined as a combination of signs and symptoms of bladder/bowel incontinence and impotence without the presence of lower limbs weakness. The purpose of the study is to assess the recovery of voiding, sexual, and sensory function in patients with isolated conus medullaris syndrome after surgical treatments.

From January 2005 to December 2012, patients with a single level burst fracture with pure conus medullaris syndrome were assessed. Level of injury, use of steroid, surgical time, surgical approach, preoperative radiographic parameters, and types of neurogenic bladder were recorded. Bladder function was evaluated using urodynamic study; sexual function was assessed by self-report questionnaire. The final outcomes were focused on the recovery of voiding, sexual, and sensory function.

Eight patients met the criteria of pure conus medullaris syndrome with thoracolumbar burst fracture. The injury level were all located at L1 vertebra. There were 6 males and 2 females. Four patients had overactive neurogenic bladder, and the other 4 patients had underactive type. At final, five patients regained self-voiding function, and three required intermittent catheterization. Two male patients were sexually active, and four male patients had some sexual dysfunction. Two female patients could have normal sexual intercourse but the frequency decreased. One female patients had prolonged perineum numbness at final follow-up.

Although extremely rare, pure conus medullaris syndrome may occur with L1 burst fracture. Despite surgical treatment, only one half of the patients regained normal bladder and sexual function.