Recurrent tethering: A common long-term problem after lipomyelomeningocelerepair

The authors reviewed the records of 94 patients who underwent initial repai r of a lipomyelomeningocele between 1982 and July 1996 at the Children's Ho spital of Pittsburgh to determine the incidence and time course of symptoma tic retethering, In each of these patients, the initial operative goals wer e to microsurgically debulk as much of the lipoma as possible to allow the conus to move freely within the spinal canal, to divide any tethering arach noidal adhesions, to close the pia if possible and to reconstitute a capaci ous thecal sac, using a dural graft if necessary. With a median follow-up o f 58 months, 19 of these patients (20.2%) required 28 subsequent operations for symptomatic retethering. Median time between the initial procedure and reoperation for retethering was 52 months. The primary complaint of 12 pat ients was intractable low-back or leg pain, Other common symptoms were prog ressive bowel and/or bladder dysfunction, deterioration of motor function a nd foot deformities, The decision to reoperate was based predominantly on t he clinical situation of the patient; magnetic resonance imaging was used t o confirm the location and extent of tethering, Patients with transitional lipomas had a significantly higher frequency of symptomatic retethering tha n those with caudal or dorsal lesions (p < 0.05), No other clinical or tech nical feature correlated with an increased frequency of retethering. In par ticular, none of a variety of types of dural graft materials appeared to en tirely prevent symptomatic retethering, Following reoperation, pain complai nts resolved and many of the other symptoms improved partially or resolved completely. Although the long-term results were also favorable in the major ity of patients, a small subgroup (n = 6) exhibited repetitive symptomatic tethering that proved increasingly difficult to treat. We concluded that sy mptomatic retethering is a common problem in children with lipomyelomeningo celes, even after an adequate initial operation, To date, no type of graft material has been shown to entirely prevent this problem, Close long-term s urveillance of such patients is required to allow detection and treatment o f symptomatic retethering.