Irreducible Locked Symphysis Pubis Disruption Caused by Incarcerated Urinary Bladder in a 14-year-Old Boy, a Case Report and Review of the Literature

Introduction

Pediatric pelvic fractures (PPF) are rare injuries; their incidence ranges from 1.6 to 20% of pelvic fracture patients.^1,2 As it entails a vulnerable population with possible long-term sequelae, the management decision should be based on the nature of the fracture and the patient’s condition to obtain excellent outcomes.^3,4

Owing to the skeleton immaturity, the pediatric pelvis differs from the adult pelvis in its inherent flexibility secondary to the lax symphysis pubis and sacroiliac joint; moreover, the abundant cartilaginous coverage serves as a shock absorber, so a pelvic fracture in pediatric patients signifies a significant injury and sometimes indicate multisystem trauma.^1,5–7 Furthermore, pediatrics with pelvic injuries are vulnerable to long-term sequels, including growth disturbance, pelvic asymmetry, leg‐length discrepancy, limping, secondary scoliosis, and chronic pain with subsequent affection of the patient function and quality of life.^3,4,8

Management options could be broadly divided into nonoperative or operative; the latter should be selected in cases with severely displaced fractures, grossly unstable fractures, and cases where nonoperative management could not achieve acceptable fracture reduction.^3,9,10

One possible factor related to displaced pelvic ring fracture irreducibility, including symphyseal disruption, is soft tissue entrapment at the fracture site, such as entrapment of the intestine or urinary bladder, which, if not diagnosed preoperatively or even noticed intraoperatively, could lead to undue soft tissue iatrogenic injuries with subsequent complications.^11–13

Most of the reports on urinary bladder incarceration after symphyseal disruption included adult patients;^14–23 in the current case report, we described a case of bladder entrapment within symphyseal disruption in a 14-year-old boy, which was discovered intraoperatively and managed effectively.

Case Report

This case report was prepared according to the CARE guidelines.²⁴

Patient Details and Initial Assessment

A 14-year-old boy presented to our emergency department after a fall from a height (from the second floor, about four meters height); his main complaint was abdominal and pelvic pain with an inability to bear weight. Initial assessment and management were carried out in accordance with ATLS guidelines and our institutional protocol for managing suspected pediatric pelvic fractures.²⁵

Upon completion of the primary ATLS survey, the pelvic anterior-posterior (AP) view showed symphyseal pubis disruption with fracture of the right pubic rami. Pelvis inlet and outlet plain radiographic views and a pelvic CT scan confirmed the diagnosis and excluded the presence of other concomitant injuries (Figure 1). Furthermore, the abdominal and pelvic ultrasound showed no abnormality.

Figure 1 Preoperative imaging studies, plain radiographs: (A) anteroposterior view. (B) Inlet view. (C) Outlet view. (D) computed tomography different scans. The red arrowheads indicate the locked symphyseal disruption and the green arrowheads indicate the right pubic rami fractures.

The decision was made to manage the patient operatively, and he was admitted to the inpatient ward after having a urinary catheterization in the emergency department.

Surgical Intervention

Surgery was performed seven days after the injury and after obtaining informed consent from the patient’s parents. The plan was to unlock the symphyseal disruption and anterior pelvic ring fixation using a symphyseal plate, and placing a retrograde trans-pubic screw was optional and to be determined intraoperatively based on the stability of the pelvis after placement of the plate.

While the patient was supine, under general anesthesia, and through the Pfannenstiel approach, steady soft tissue dissection was started to identify the urinary bladder (as part of the surgical approach, which should be then swept proximally); however, the surgeon was unable to identify the exact nature of the soft tissue structure (Figure 2).

Figure 2 Intraoperative images. (A) after performing the Pfannenstiel incision (white arrowhead), initial soft tissue dissection, and retractor placement, a soft tissue mass (the urinary bladder) was evident in the field (white asterisk), hindering the fracture reduction. (B) after placement of more retractors, the urinary bladder (white asterisk) was dissected from the surroundings. (C) a Schanz screw (red arrowhead) was placed on the right pubic rami to ease fracture manipulation. (D) after gentle manipulation of the fracture, the right pubic rami (yellow arrowhead) and the left pubic rami (green arrowhead) started to be evident through the surgical approach, while the urinary bladder (white asterisk) is freed from the entrapment side and swept proximally. (E and F) after complete dissection and reduction of the urinary bladder, the overlapping of the locked symphyseal disruption is evident.

Instead, the surgeon decided to start soft tissue dissection from as lateral as possible (from the intact left pubic rami) and proceed medially; upon reaching the right pubic rami, a soft tissue mass was found to be entrapped between the anteriorly displaced left pubic rami and the posteriorly displaced right pubic rami, which was the urinary bladder.

In the absence of posterior pelvic ring injury, it was difficult to over-distract the pelvis at the fracture site to deliver the entrapped urinary bladder safely; instead, a Schanz screw was placed in the right superior pubic ramus and in the left supraacetabular area to help in inducing controlled external rotation to the pelvis, then two screws were applied, one on each superior pubic rami, and a Jungbluth distractor was applied to provide assisted symphyseal distraction and rotatory manipulation (Figure 3).

Figure 3 Intraoperative fluoroscopic images indicating the steps of symphyseal disruption reduction and internal fixation. (A and B) initial imaging before fracture manipulation showing the locked symphyseal disruption (red arrowheads). (C) a Schanz screw was placed in the right pubic rami (blue arrowhead), and another one was placed in the left supraacetabular area (black arrowhead). One screw was inserted in the pubic rami on each side (green arrowhead) for Jungbluth distractor assembly. (D and E) after attaching the Jungbluth distractor (white arrowhead), symphyseal disruption reduction was achieved; it is noted that the Orange arrowhead throughout the images indicates the abdominal towel placed in the retropubic space of Retzius. (F) after obtaining preliminary optimum reduction, it was held using a temporary K-wire (yellow arrowhead). (G) the initial plate application and initial fixation, while the K-wire (yellow arrowhead) is still in place. (H) after final internal fixation using a symphyseal plate.

After achieving optimum distraction of the symphyseal disruption, an assistant held the distractor while the main surgeon carefully dissected the urinary bladder, making sure it was intact, swept it proximally, and placed an abdominal towel in the retropubic space of Retzius (Figure 3). At all steps, we ensured that the urine collecting bag showed clear urine and no hematuria.

Subsequently, the fracture was reduced and stabilized by a six-hole pre-contoured locked plate, and the last screw on the right side crossed the pubic rami fracture site.

On the immediate postoperative plain radiographs, diastasis of the right sacroiliac joint was noted (which we attributed to aggravation of a subtle injury after fracture reduction manipulation) (Figure 4), and the decision was made to perform percutaneous transiliac trans-sacral screw fixation, which was performed during the same hospital stay.

Figure 4 Immediate postoperative radiographs (A) anteroposterior. (B) inlet. (C) outlet views show symphysis pubis reduction, correct plate placement, and screws length; however, it was noted that the sacroiliac joint on the right side was disrupted (indicated by red arrowheads).

Follow up Protocol and Outcomes

We sought advice from a urology consultant immediately postoperatively, who assured us that no particular intervention was needed and advised keeping the urinary catheter for two weeks in case an intimal injury had occurred during surgical manipulation. Furthermore, neurovascular evaluation was deemed normal.

During the hospital stay (five days), the radiographic assessment was obtained on the first postoperative day (pelvis AP, inlet, and outlet views) to ensure fracture reduction and hardware position. The suction drain was removed on the second postoperative day. The patient was discharged on the third postoperative day after counseling with a physiotherapy specialist who advised the patient and his parents on the postoperative rehabilitation protocol.

Follow-up visits were scheduled one week postoperative for wound assessment, and sutures were removed after two weeks. At a six-week visit, a new set of plain radiographs was obtained to assess fracture healing, and accordingly, the patient was advised to start partial weight bearing. Then, a follow up visit at three months showed complete fracture union (Figure 5), the patient was walking normally without support, and the functional status was excellent (score of 89 points), according to the modification of Majeed’s functional scoring system.^25,26

Figure 5 Plain radiographs (A) anteroposterior. (B) inlet. (C) outlet views obtained at the final follow up (at three months) showed the addition of a transiliac screw (which was inserted to fix the posterior element disruption), maintained symphyseal reduction, and union of the right pubic rami fracture.

Discussion

Associated urinary bladder injury with pelvic fracture ranges in severity from just contusion to complete rupture.²⁷ The injury could occur by direct penetration by the fracture end, or by shearing forces through its ligamentous attachment, and it could be an iatrogenic injury if the surgeon did not anticipate such a situation.^22,28

Various authors reported on urinary bladder incarceration or entrapment preventing pelvic fracture reduction (Table 1). The current case report is one of the few reports describing urinary bladder entrapment preventing pelvic fracture reduction in a pediatric patient. We were able to diagnose such bladder entrapment intraoperatively, which caused irreducibility of the symphyseal disruption, and it was managed successfully using specific pelvic fracture tools (Jungbluth distractor) and Schanz screws around the fracture to ease fracture manipulation and to ease safe bladder reduction to its position.

Table 1 Summary of the Reports Published in the Literature Discussing Urinary Bladder Entrapment or Incarceration During Pelvic Fracture Management

Clinical signs raising suspicion of a concomitant urinary bladder or urethral injury include blood at the urethral meatus, difficult or failed urinary catheterization (in case of urethral injury), a high-riding prostate gland, scrotal ecchymosis, gross hematuria after successful catheterization, and microscopic hematuria on urinalysis.^17,27,29 However, diagnosing such injuries can be challenging, but if suspected, a retrograde urethrogram before catheterization and CT with contrast could be helpful.²⁷ Furthermore, some authors diagnosed this injury after obtaining an MRI.^16,18

Such an injury could pass unnoticed preoperatively;³⁰ in the current case, we reviewed the preoperative CT images and sought a radiology consultant’s opinion, and we could not define any abnormality confirming the diagnosis of bladder entrapment.

In the report by Stenquist et al,²² the authors reported that the physical exam was negative (no blood at the urethral meatus and no scrotal ecchymosis) and negative FAST examination; however, the bladder tear was diagnosed intraoperatively under direct vision, the reason for that was attributed to the nature of the bladder tear which affected the outer layer only without deep penetration. The same normal clinical evaluation was also reported in a report by Finnan et al.¹⁷

The management of concomitant bladder entrapment or injury relies on the extent and location of the injury and whether it is intra- or extraperitoneal. A Foley catheter for a few days or weeks is enough for an extraperitoneal rupture, while intraperitoneal ruptures require surgical repair.^28,31

The incarcerated urinary bladder could be a cause for non-reducible pelvic fractures, including symphyseal disruption, especially when the initial management was nonoperative or closed reduction and external fixation. The previous scenario was reported in some cases in the literature and should be anticipated from the fracture pattern.^17,18,21 This injury necessitates relieving the external fixation and reducing the bladder through open surgery or even converting the external fixation into open reduction and internal fixation with a concomitant bladder repair (if required) and reduction.

We admit that the current report has some limitations. First, the management details could not be generalized as we reported only a single case. Second, we did not provide longer follow up to detect any growth disturbance or long-term sequels of pediatric pelvic injuries.

Conclusion

Urinary bladder entrapment within pelvic fractures, including symphyseal disruption, could be the cause of fracture or symphyseal irreducibility. Suspicion of such a situation could be based on clinical examination preoperative imaging studies, and sometimes, it could only be anticipated and discovered intraoperatively. Careful soft tissue dissection and using appropriate fracture reduction tools and techniques are required to achieve gentle reduction of the incarcerated bladder wall and correct reduction and stable fixation of the pelvic disruption.