Unstable sacral fracture with neurogenic bladder and bowel dysfunction following high energy trauma: a case report

INTRODUCTION

Sacral fractures are uncommon injuries accounting for approximately 1–5% of all spinal fractures and up to 30–45% of pelvic ring injuries following high-energy trauma such as road traffic accidents and falls from height. These fractures are frequently associated with severe soft-tissue injury, pelvic instability, and multiple system trauma, contributing to significant morbidity and mortality.^1,2

Because of the complex anatomy of the sacrum and overlapping bowel shadows on plain radiographs, sacral fractures are often missed during the initial evaluation. Several studies have reported delayed or missed diagnoses in up to one-third of patients, particularly in those with associated pelvic injuries. Computed tomography (CT) with multiplanar and three-dimensional reconstruction has therefore become the imaging modality of choice for accurate diagnosis, fracture classification, and preoperative planning.^3,4

The Denis classification remains the most widely accepted system for categorizing sacral fractures according to their anatomical location and associated neurological risk. Zone II and zone III fractures have a substantially higher incidence of sacral nerve root or cauda equina injury, frequently presenting with sensory disturbances, motor weakness, and bladder or bowel dysfunction. Neurological impairment is one of the most important determinants of long-term functional outcome in these patients.^5,6

The management of unstable sacral fractures with neurological deficit remains challenging. Although conservative treatment may be appropriate for stable fractures without neurological compromise, clinically reported studies increasingly support early surgical decompression and stable spinopelvic or lumbopelvic fixation in patients with unstable fracture patterns and neural compression. Early intervention facilitates neural decompression, restores pelvic stability, permits early mobilization, and may improve neurological recovery while reducing complications associated with prolonged immobilization.^7,9

We present a case of an unstable Denis zone II–III sacral fracture with neurogenic bladder and bowel dysfunction following high-energy trauma that was successfully managed with early posterior decompression and lumbopelvic fixation. The case highlights the importance of prompt diagnosis using advanced imaging, timely surgical stabilization, and multidisciplinary postoperative rehabilitation in achieving favourable neurological and functional outcomes.

CASE REPORT

A 24-year-old female presented after a road traffic accident with severe lower back pain, pelvic pain, and urinary retention. Examination revealed decreased perianal sensation and reduced voluntary anal contraction, while lower limb motor power was preserved. CT scan demonstrated an unstable Denis type II–III sacral fracture with canal involvement. An undisplaced calcaneal fracture was managed conservatively. Early posterior decompression and lumbopelvic fixation were performed. The postoperative period was uneventful. Gradual neurological recovery was observed, with restoration of bladder and bowel function and independent ambulation at follow-up.

Radiological evaluation

Plain radiograph of the pelvis showed subtle irregularity in the sacral region, raising suspicion of a sacral fracture (Figure 1).

Given the clinical findings and equivocal radiographic appearance, a CT scan of the pelvis and lumbosacral spine was performed.

CT imaging revealed an unstable sacral fracture extending through the sacral foramina with involvement of the central canal, consistent with a Denis type II–III fracture. Axial, coronal, and sagittal CT images demonstrated fracture lines traversing the sacral ala and body with potential sacral nerve root compression, Three-dimensional CT reconstruction further delineated the fracture configuration and instability, aiding in surgical planning (Figure 2).

Additionally, the patient was found to have an undisplaced fracture of the right calcaneum, which was planned for conservative management.

Surgical management

Given the unstable nature of the fracture and the presence of neurological deficit, early surgical intervention was planned. The patient was positioned prone on a radiolucent table. Posterior midline approach was used to expose the lumbosacral region.

Posterior decompression of the sacral canal was performed to relieve neural compression. Lumbosacral pelvic fixation was achieved using pedicle screws in the lumbar vertebrae and sacrao- iliac screws bilaterally, connected with rods to provide stable fixation. Intraoperative C-arm fluoroscopy was used to confirm correct placement of screws and adequate alignment, (Figure 3). The wound was closed in layers over a drain.

Postoperative course and follow-up

The postoperative period was uneventful. The patient was mobilized gradually with support after pain control.

Postoperative anteroposterior and lateral radiographs of the pelvis and lumbosacral spine confirmed satisfactory implant placement and stable fixation (Figure 4).

Neurologically, the patient showed gradual improvement. Bladder function began to recover, and the Foley catheter was removed after successful trial voiding. Bowel function also improved progressively. At follow-up, the patient was able to ambulate independently without support.

Clinical photographs at follow-up demonstrated a well-healed posterior surgical scar without complications (Figure 5d). Functional recovery was evident with improved posture, standing

Balance, and single-leg stance, indicating good neurological and musculoskeletal recovery (Figure 5a-c).

DISCUSSION

Sacral fractures are uncommon but potentially devastating injuries, usually resulting from high-energy trauma and frequently associated with pelvic ring disruption and multisystem injuries. Neurological deficits occur in approximately 20–50% of unstable sacral fractures, particularly in Denis zone II and zone III injuries, because of involvement of the sacral nerve roots and central sacral canal. Our patient sustained a high-energy road traffic injury with an unstable Denis zone II–III fracture associated with neurogenic bladder and bowel dysfunction, consistent with the neurological patterns described in previous studies.^1-3

Early diagnosis of sacral fractures remains challenging because plain radiographs may fail to demonstrate fracture lines owing to the complex sacral anatomy and overlapping bowel shadows. In our patient, the initial pelvic radiograph suggested only subtle sacral irregularity, whereas computed tomography clearly demonstrated fracture extension through the sacral foramina with central canal involvement. This observation agrees with previous studies showing that multidetector CT with multiplanar and three-dimensional reconstruction is the gold standard for identifying fracture morphology, assessing instability, and planning surgical intervention.^4,5

Neurological impairment is one of the strongest predictors of long-term functional outcome after sacral fractures. Neurogenic bladder and bowel dysfunction indicate injury to the sacral nerve roots or cauda equina and are associated with significant disability if treatment is delayed. In our patient, decreased perianal sensation, reduced voluntary anal contraction, and urinary retention were the principal neurological findings. Similar neurological presentations have been reported by Denis and subsequent investigators, who demonstrated a higher incidence of neurological deficits in zone III fractures and combined zone II–III injuries.^6,7

The optimal timing of surgical decompression remains an area of ongoing discussion; however, increasing evidence supports early decompression in patients with neurological deficits and radiological evidence of neural compression. Early surgery minimizes persistent neural compression, facilitates neurological recovery, and allows earlier rehabilitation. In the present case, posterior decompression was performed soon after diagnosis, resulting in progressive recovery of bladder and bowel function. These findings are consistent with reports by Vaccaro and colleagues and other contemporary series demonstrating improved neurological outcomes following early decompression compared with delayed intervention.^8,9

Stable fixation is equally important in the management of unstable sacral fractures. Lumbopelvic fixation provides rigid stabilization by linking the lumbar spine to the pelvis, effectively resisting vertical, rotational, and shear forces while allowing early mobilization. Biomechanical and clinical studies have demonstrated that lumbopelvic fixation provides excellent stability in vertically unstable sacral fractures and facilitates fracture union with low rates of fixation failure. In our patient, rigid lumbopelvic fixation achieved satisfactory alignment, maintained fracture stability, and permitted progressive mobilization without implant-related complications, findings comparable to previously published reports.^10,11

Functional recovery following unstable sacral fractures depends on the severity of neurological injury, timing of decompression, adequacy of stabilization, and structured rehabilitation. Our patient demonstrated gradual recovery of bladder and bowel function together with independent ambulation during follow-up. Similar improvements have been described in recent studies where early decompression combined with stable lumbopelvic fixation resulted in superior neurological and functional outcomes compared with delayed treatment or non-operative management.^12,13

Although this report describes a single patient, it reinforces current evidence supporting early recognition, CT-based assessment, timely neural decompression, and rigid lumbopelvic fixation in unstable sacral fractures associated with neurological deficits. Larger prospective multicentre studies with longer follow-up are required to determine prognostic factors influencing neurological recovery and to establish standardized treatment protocols for these complex injuries.

CONCLUSION

Early diagnosis, detailed imaging, and timely decompression with lumbopelvic fixation can lead to good neurological and functional recovery in unstable sacral fractures with bladder and bowel dysfunction.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: Not required

REFERENCES

1. 1. Denis Francis, Davis S, Comfort T. Sacral fractures: an important problem. Clin Orthop Relat Res. 1988;(227):67-81.
2. 2. Routt ML Jr, Simonian PT, Ballmer F. A rational approach to pelvic trauma. Clin Orthop Relat Res. 1995;(318):61-74.
3. 3. Schildhauer TA, Bellabarba C, Nork SE, Barei DP, Routt ML Jr, Chapman JR. Decompression and lumbopelvic fixation for sacral fracture-dislocations with spinopelvic dissociation. J Orthop Trauma. 2006;20(7):447-57.
4. 4. Keating JF, Werier J, Blachut P, Broekhuyse H, Meek RN, O'Brien PJ. Early fixation of the vertically unstable pelvis: the role of iliosacral screw fixation. Injury. 1999;30(9):619-25.
5. 5. Vaccaro AR, Kim DH, Brodke DS, Harris M, Chapman JR, Schildhauer T, et al. Diagnosis and management of sacral spine fractures. Instr Course Lect. 2004;53:375-85.
6. 6. Tile M. Acute pelvic fractures: I. Causation and classification. J Am Acad Orthop Surg. 1996;4(3):143-51.
7. 7. Bellabarba C, Schildhauer TA, Vaccaro AR, Chapman JR. Complications associated with surgical stabilization of high-grade sacral fracture-dislocations. Spine. 2006;31(11 Suppl):S80-8.
8. 8. Lindahl J, Hirvensalo E. Management of sacral fractures. Eur J Trauma Emerg Surg. 2005;31(5):439-46.
9. 9. Roy-Camille R, Saillant G, Gagna G, Mazel C. Transverse fracture of the upper sacrum: Suicidal jumper's fracture. Spine. 1985;10(9):838-45.
10. 10. Routt ML Jr, Nork SE, Mills WJ. Percutaneous fixation of pelvic ring disruptions. Clin Orthop Relat Res. 2000;(375):15-29.
11. 11. Schildhauer TA, Josten C, Muhr G. Triangular osteosynthesis of vertically unstable sacrum fractures. Eur Spine J. 2002;11(2):152-7.
12. 12. Huittinen VM, Slätis P. Fractures of the sacrum. Acta Orthop Scand. 1972;43(4):361-8.
13. 13. Isler B. Lumbosacral lesions associated with pelvic ring injuries. Injury. 1990;21(Suppl 1):S6-S10.
14. 14. König MA, Jehan S, Boszczyk BM. Sacral fractures and neurological injury: current concepts. Eur Spine J. 2012;21(5):829-40.
15. 15. QSabiston CP, Wing PC. Sacral fractures: classification and neurological implications. Spine. 1986;11(2):146-9.