Long-term functional and radiological outcome after displaced sacral fractures

Background and objectives Displaced, unstable sacral fractures are severe injuries resulting in considerable morbidity and functional sequelae. Several authors report neurologic deficits, bladder, bowel, and sexual dysfunction, as well as residual pain and poor self-reported health, in short, and medium-term follow-up studies. However, there is a lack of information on long-term functional outcome following these injures, nor whether any changes occur in functional status many years after the initial injury. The aim of this study was to assess long-term outcome in patients after displaced sacral fractures in a 10-year perspective, focusing on dysfunctions related to the pelvic trauma and the sacral fracture. Also, by comparing the long-term outcome results with the medium-term results, changes over time could be assessed to gain more information on the development of these relatively uncommon injuries. In addition, we aimed to assess the long-term functional outcome in patients with a rare subgroup of sacral fractures, namely traumatic lumbosacral dissociation injuries. Materials and methods The present study included two clinical series, one prospective (papers 1-3) and one retrospective (paper 4). The study was conducted at Oslo University Hospital- Ullevaal (OUSU), where all patients with displaced, unstable sacral fractures were prospectively registered between 1996 and 2001 (papers 1-3). During this period, 39 patients were registered; all of whom underwent operative treatment at OUS-U, with subsequent discharge to a rehabilitation facility at Sunnaas Hospital for the majority of the patients. Tötterman et al followed 32 of the 39 patients, and published the results of functional outcome in a 1-year follow-up. In the present study, 28 of the 32 patients were available for a 10-year follow-up. Patients with traumatic Lumbosacral Dissociation (TLSD), constituting the material in Paper- IV, were retrospectively identified from the Pelvic Fracture Register at Orthopaedic department, OUS-U, between 1997 and 2006. Out of 21 eligible patients, 15 were available for follow-up, mean seven years post-injury. Seven were treated operatively and eight were treated non-operatively. All patients were examined and the following data were collected: Neurologic function in lower extremities and perineum (ASIA), bladder function (uroflowmetry, residual urine measurement, and interview), bowel function (interview), sexual function (interview, and IIEF questionnaire in males), pain (VAS), ambulation (interview and observation), ADL and return to work/employment status (interview), and patient-reported health (SF-36). In addition, all patients underwent radiologic assessment with conventional radiographs and CT of lower lumbar spine and the pelvis. Results Papers 1-3: All but one patient had neurologic deficits, but only two were wheelchair users. The most commonly affected dermatomes were L5 and S1. No significant changes in neurologic function were noted over time. Nineteen out of 28 had pathologic urinary function, with a significant deterioration noted in 11 since the 1-year follow-up. Eight patients reported bowel dysfunction and 12 had problems associated with sexual activities; none of these parameters was significantly changed from the previous follow-up. Radiographic assessment revealed that all sacral fractures were united, with residual displacement (RD) in the posterior pelvic ring ≥ 10 mm in 16 patients. Narrowing of one or more sacral neural root foramen was observed in 26 and postforaminal bony encroachment of the L5 nerve in 22 patients. Narrowing of the sacral foramina, as well as postforaminal impingement/ bony encroachment of L5 nerve correlated significantly with neurologic deficits. No significant correlations were found between radiologic findings and pain. The SF-36 scores among these patients were overall lower than the normal scores (Norwegian population), with no significant changes from the 1-year follow-up. The 10-year SF-36 scores showed significant correlations with pain, sexual, and bowel dysfunction, but not with neurologic deficits or urinary dysfunction. Paper 4: Only two out of 15 patients had normal neurologic function and both were treated non-operatively. In the remaining 13 patients with neurologic deficits, one patient who was treated non-operatively had no neurologic symptoms initially, but developed secondary motor and sensory deficits bilaterally from L5-S4. Radiologic examination showed massive callus formation around the fracture site at the upper end of the sacrum, with a marked narrowing of the central canal at the S2 level. Eleven had pathologic urinary function, five reported bowel dysfunction, and 10 reported limitations in sexual function, seven of whom complained of pain during intercourse. All but one patient reported pain at follow-up, with the majority having lumbosacral pain combined with radicular pain. All sacral fractures were healed with kyphotic angulation across the fracture. In four cases, there was an increase in kyphosis compared with initial radiographs. Patients with TLSD had significantly lower SF-36 scores than the normal population. Conclusion In this long-term follow-up study, we found that patients with displaced sacral fractures had considerable morbidity and disabilities. We found high rates of neurologic deficits, with no significant changes over time, suggesting that neurologic deficits at the time of initial presentation may be permanent if still present one year post-injury. Problems with urogenital functions were common findings; with urinary dysfunction showing a significant deterioration over time, and high rates of sexual dysfunctions were reported. In addition, the patientreported health was significantly lower than the norms, with no changes over time, and with a significant correlation with pain. These results imply that a special focus on these findings is needed during the rehabilitation period, with longer follow-up period and a multidisciplinary approach across specialties. Pathological radiographic findings were common, including residual displacement in the posterior pelvic ring that did not correlate with lumbosacral pain