J Orthop Sci DOI 10.1007/s00776-013-0527-6
CASE REPORT
Modification of spinal pedicle screw-plate fixation for bilateral pediatric pelvic ring injury in 2-year-old girl Paphon Sa-ngasoongsong • Norachart Sirisreetreerux • Pongsthorn Chanplakorn • Patarawan Woratanarat • Chanyut Suphachatwong • Pornchai Mulpruek
Received: 18 October 2013 / Accepted: 20 December 2013 Ó The Japanese Orthopaedic Association 2014
Background Unstable pelvic fractures in children are an uncommon injury and are typically associated with high-energy trauma, such as an automobile accident or motor vehiclepedestrian injury [1–3]. Results from recent studies concluded that these unstable injuries needed to be treated with operative management [4–9], to achieve as near anatomical reduction as possible, with stable fixation to prevent longterm poor outcomes following non-operative treatment, such as residual pain, limb length discrepancy and scoliosis [10, 11]. Nevertheless, to date, there is still no consensus treatment option for surgical management in pediatric pelvic fracture, especially in very young children with displaced sacroiliac (SI) fracture-dislocation or bilateral SI joint injury. Traditional surgical fixation methods of SI joint disruptions, such as SI screw and anterior retroperitoneal SI plate, have several limitations because of the small bony anatomy in children, which requires an experienced surgeon and advanced imaging techniques. Moreover, there are still possible catastrophic intraoperative complications such as extensive blood loss, neurovascular injury, and implant jam due to the small bony architecture [12]. Therefore, in this present study, the authors aimed to introduce a new alternative surgical fixation procedure by modifying a spinal pedicle screw-plate (PSP) system to
P. Sa-ngasoongsong N. Sirisreetreerux P. Chanplakorn P. Woratanarat C. Suphachatwong P. Mulpruek (&) Department of Orthopedics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270, Rama VI Road, Ratchathewi, Bangkok 10400, Thailand e-mail: [email protected] P. Sa-ngasoongsong e-mail: [email protected]
treat a complex bilateral unstable SI joint fracture-dislocation in a very young pediatric patient with a minimally invasive technique, and to report the mid-term result.
Case report Case presentation A 2-year-old girl sustained a crush injury on her pelvis and right leg in a pedestrian-vehicle accident, which was caused by a six-wheeled truck running over her lower trunk. She was initially sent to a nearby hospital for emergency treatment. The primary survey showed good consciousness but she was in a state of shock, with positive tenderness and marked swelling on her pelvis. She had initially been treated with emergency endotracheal intubation, fluid resuscitation and pelvic wrapping. The initial radiographs and emergent computed tomography (CT) were taken, after achieving a stable hemodynamic status, and showed right SI fracture-dislocation, left SI joint dislocation, and left pubic rami fractures (Torode and Zieg classification type IV [13], and AO/OTA classification type C2 [14]) without other internal organ injury (Fig. 1). The diagnosis was open and bilateral unstable pelvic fracture with perineal and anal tear, left sciatic nerve injury, multiple deep pelvic lacerated wounds, and skin loss on right leg. Therefore, she was treated by emergency debridement with anterior pelvic external fixator, diverting colostomy, and wound debridement. Due to the severity of injuries, she was referred to our hospital on the 2nd day after injury for definitive treatment. On admission, the patient was in a stable condition but was still intubated and required a mechanical ventilator for respiratory support. Serial wound debridement was
123
P. Sa-ngasoongsong et al.
Fig. 1 Initial radiograph and computerized tomogram (CT) images under pelvic wrapping; portable pelvic radiograph after emergent urethrogram (a) showed displaced pelvic ring fractures on both sides (arrows). Axial CT (b) and three-dimensional CT images (c) further
demonstrated left sacroiliac (SI) joint dislocation (asterisk), right sacroiliac (SI) fracture-dislocation (thick arrow) and left pubic rami fracture (thin arrow) without obvious triradiate cartilage injury
Fig. 2 Postoperative radiographs after external fixator application; pelvic anteroposterior (a), inlet (b), and outlet (c) views revealed unstable bilateral posterior pelvic ring injury with asymmetrical deformity and 6-cm anterior pubic symphyseal widening (double head arrow) which could not be controlled with an anterior external fixator
performed to prevent infection. Intra-operative findings showed unstable and displaced pelvic fracture-dislocation on bilateral sides and an anterior external fixator was unable to achieve stability and reduce the fracture anatomically, as shown in postoperative radiographs (Fig. 2). Unfortunately, external stabilization with a pelvic C-clamp was considered impossible in this case because of the risk of intra-pelvic pin penetration from the transiliac fracturedislocation on the right side. Additionally, the application of a relatively large pin in a very small pelvis would increase the risk of damaging other vital structures; such as the sciatic nerve or triradiate cartilage. On the 9th day after
123
injury and after three debridements, the patient’s condition was improved and all wounds had no sign of infection. Preoperative planning for definitive treatment of the pelvic fracture was then discussed in detail. The goals of treatment in this patient were the same as for unstable pelvic fracture treatment: to create a symmetrical pelvis with stable fixation and to avoid early and long-term complications of surgical fixation [5–9]. Generally, the popular surgical fixation methods for posterior pelvic ring injury in children are SI screw and anterior retroperitoneal SI plate. However, these options had several limitations in this patient. SI screw insertion required surgical expertise and
Bilateral pediatric pelvic fracture
advanced imaging techniques, especially in this toddler patient with a very small sacral corridor and who had bilateral SI joint disruption. Moreover, using bilateral SI screws could be more difficult due to risk of implant jam. An anterior retroperitoneal SI plate was also not a good option due to needing extensive exposure, resulting increased blood loss, risk of L5 nerve root damage, and risk of infection from other pelvic wounds, especially from the colostomy site [12]. Therefore, we designed a new fixation method, modifying the spinal pedicle screw-plate (PSP) system to stabilize this bilateral posterior pelvic ring injury in this very young patient. Surgical techniques After general anesthesia, the patient was placed in a prone position, on a radiolucent table, with bolster support on her chest and proximal thigh to prevent pressure on the abdomen and both iliac crests (Fig. 3a). Anterior external fixator clamps were also released before starting the operation to allow easier fracture reduction. Surgery was performed by using a bilateral posterior SI joint approach and the PSP system (T.K.S. Metal Works Co. Ltd, Bangkok, Thailand). The PSP system is a spinal fixation system which was conventionally designed for treating varieties of spinal diseases [15–18]. The system is a constrained lock design
Fig. 3 Intraoperative images and three-dimensional animation model. Intraoperative pictures show (a) the surgical setting in prone position, and surgical incision (b) as bilateral vertical incisions with pedicle screw insertions (arrows) at 1-cm below the posterior superior iliac spine (PSIS). Pelvic model pictures before (c) and after plate
using a thread plate and an identical thread washer, locking together by a compressive nut [19]. A 5-cm longitudinal incision over the posterior superior iliac spine (PSIS) was created on both sides, and then the superficial dissection preceded down to PSIS with a full thickness flap for preserving the blood supply. The pedicle screw entry point was designed to be at 1 cm below the PSIS in order to prevent prominence of the screw head and plate (Fig. 3b). Moreover, due to the locking screw head system, this same anatomical entry point would assist in the reduction of the sacroiliac fracture-dislocation or dislocation of both sides at the same level after applying the spinal plate (Fig. 3c–e). After the entry point was made, using a little curettage, the screw tract was created in an anteriorly forward direction, into the supra-acetabular region between the outer and inner cortex of the ilium. After measuring the depth and checking for perforation with blunt smooth K-wire, a 40-mm-long, 6.5-mm-diameter pedicle screw was inserted on each side. Then a subcutaneous tunnel between those two screws was developed above the fascia layer of the lower sacrum, and used for inserting a precontouring 90-mm spinal plate through this tunnel. One pedicle screw was initially locked to allow easier fracture control. After that, the closed reduction of the posterior pelvic ring was done with manual compression on both posterior iliac crests, leg traction, and the constraining effect from the
application (d), demonstrate the reduction (thick arrows) by the constraint of the pedicle screw plate (PSP) system (thin arrow). Fluoroscopic image (e) demonstrates the nearly anatomical reduction of the pelvic ring after applying the spinal plate
123
P. Sa-ngasoongsong et al.
locking system of the contralateral screw against the precontouring plate, as seen in Fig. 3c–e). Finally, pelvic fracture alignment and stability was tested under a fluoroscope, and demonstrated that the fracture was stable enough without needing anterior support. Therefore, the anterior external fixator was removed at the end of the operation and wound closure was performed without using a drain. The total operative time was 45 min and minimal blood loss was encountered. Postoperative care and rehabilitation Postoperatively, the patient was allowed to start progressive ambulation from bed rest to sitting rehabilitation during the first 3 months, and this was followed by progressive weight bearing, as tolerated, with a gait aid. She had stayed in the hospital for 4 weeks due wound care and was discharged without complication. The fractures healed uneventfully, as shown in postoperative follow-up images (Fig. 4). Implant removal was done at 6 months, and she
Fig. 4 Postoperative radiographs and CT scan images at 4 weeks; postoperative pelvic anteroposterior (a), inlet (b), and outlet (c) views reveal nearly anatomical reduction with symmetrical pelvic ring. The axial CT images at the S1 level (d), right pedicle screw level (e), left
123
could walk independently without pain at 9 months. The left sciatic nerve injury was fully recovered at 1 year postoperatively. At the latest follow-up period (18 months), she had no sign of serious complications such as infection, leg length discrepancy, or recurrent pelvic instability (Fig. 5). This study has been reviewed and approved by our Institutional Board, based on the Declaration of Helsinki. The patient and her family were informed that data from the case would be submitted for publication, and consent was given by the patient’s parents.
Discussion Pediatric pelvic fractures are a relatively rare condition, and are usually associated with multiple organ injuries from high-energy trauma. The most common causes are motor vehicle accident, pedestrian-automobile collision, and falls from height. Due to its severity, up to 15 % of
pedicle screw level (f) and coronal CT images (g) demonstrated anatomical reduction of sacroiliac joint with appropriate screw position
Bilateral pediatric pelvic fracture
Fig. 5 Postoperative compared radiographs at 6 months and 18 months after implant removal, and clinical compared wound pictures at 2 weeks and 6 months; pelvic anteroposterior (a), inlet (b) and outlet (c) films showed fracture union and good bone remodeling in
nearly symmetrical pelvis without sign of instability or leg length discrepancy. Clinical pictures (d) revealed no postoperative wound problem
these patients die, and 30 % of those who survive are disabled, with a long-term poor outcome [3, 6, 20, 21]. Generally, the decision as to how to treat pelvic fractures in children is based on the patient’s age, fracture classification, stability of the pelvic ring, extent of concomitant injuries, and hemodynamic stability [22]. Historically, these fractures had been treated with conservative treatment, such as pelvic sling and traction, due to the belief in the great ability of fracture healing and remodeling in children, and risks of neurovascular and triradiate cartilage injury from surgery [13, 23–26]. However, multiple longterm follow-up studies showed that using these methods in unstable pelvic and/or acetabular fractures would result in significant malreduction and unsatisfactory long-term complications, such as residual pain, limp, and scoliosis [9–11, 27]. Moreover, several recent studies, which performed operative management in unstable pelvic and acetabular fractures to achieve anatomical or near-anatomical reduction, have demonstrated a successful outcome with low incidence of complications [7, 8]. Therefore, it has been suggested that the treatment strategy of unstable pelvic fractures in children should be the same as in adults. Nevertheless, to our knowledge, there is still no consensus in surgical fixation methods in this unstable pediatric pelvic fracture, especially in very young children or in bilateral SI joint disruption.
Traditionally, the surgical fixation options in unstable pediatric pelvic fractures include anterior external fixator, SI screw, and anterior retroperitoneal SI plate; however, there are several limitations in using these methods due to their strict prerequisites and risk of specific complications [12]. Although an anterior external fixator may help in fracture stabilization in the early phase, its application cannot provide posterior ring stability, and the resulting pelvic asymmetry following this method has been shown to be greater than from nonoperative treatment [28]. SI screw application is a very demanding procedure, requiring surgical expertise and CT guidance due to a narrow safe sacral corridor in a small pediatric pelvis. Furthermore, insertion of this screw in some certain circumstances, such as in a very young patient, a patient with pelvic dysmorphism, or patients with displaced fractures and bilateral injury, would result in a greater risk of iatrogenic complications such as neurovascular injury and implant jam. An anterior retroperitoneal SI plate needs extensive exposure, resulting in greater blood loss and risk of damage of the L5 nerve root [12]. Application of the pedicle screw-plate (PSP) system in pediatric pelvic fracture, as we have introduced in this study, has many advantages. First, the surgical approach in this study is a minimally invasive approach. We just used a bilateral mini-incision posterior SI approach, with only
123
P. Sa-ngasoongsong et al.
superficial dissection at PSIS to insert the pedicle screws into the iliac bone. These screws could then be used as joy sticks (so as not to open the SI joint, and avoiding direct manipulation), after which a subcutaneous tunnel was created between the screws to insert the plate. This surgical technique results in a small amount of blood loss and lessens the risk of iatrogenic neurovascular injury. Moreover, this posterior approach is a safer approach in reducing surgical contamination in patients with an anterior pelvic wound, supra-pubic catheter, or colostomy. Secondly, the fracture stability from PSP application should be much higher than the stability from SI screw application due to the larger screws (standard pedicle screw) inserted into good quality bone in the supra-acetabular area, and the angular stability from the locking system. Therefore, the resulting fracture stability after PSP application should be sufficient to control the pelvic ring fracture without need of anterior support, as seen in Figs. 3, 4. Thirdly, several closed reduction techniques could be used with this fixation method for external compression and leg traction, manipulation from the anterior iliac crest pin, and the constraining effect from the pre-contour plate application (Fig. 3). Additionally, screw insertion in the same anatomical landmark would assist the reduction in the case of superior migration of one hemipelvis. Finally, the risk of neurovascular or triradiate cartilage injury from this technique is low due to the screw being fixed in one bone (iliac bone), the ability to check the screw tract before screw insertion, and the positioning of the screw is not close to the lumbosacral plexus, triradiate cartilage or vital structures in the pelvic cavity (Fig. 4). However, this approach also has some limitations. First, as in the other approach, the incision area on the buttock should not have a contaminated wound. Secondly, although this technique is less surgically demanding than other surgical fixation methods on the posterior pelvic ring, the authors recommend that the surgeon always uses an intraoperative fluoroscope to confirm the screw placement and the quality of fracture reduction. Thirdly, due to the need for surgical setting in the prone position, this approach should be avoided or used with caution in the patients who have concomitant internal organ injury, especially in the acute phase. Lastly, the plate should be placed at the lower sacrum level to avoid skin complications, and the implant should be removed after the fracture has healed (usually at 5–6 months after surgery) in order to allow normal growth of the pelvic bone.
Conclusion Application of a pedicle screw-plate (PSP) system with a minimally invasive posterior approach is a possible
123
surgical option for definitive fixation in unstable pediatric pelvic fractures. We believe that this method is a safe and very useful technique, especially in very young children and those having bilateral injury. However, pre-operative planning, correct surgical technique, accurate direction of screw placement, and intraoperative fluoroscope imaging are needed. Acknowledgments The authors are thankful to Professor Wichien Laohachareonsombat, M.D., who kindly helped as a senior consultant, and thank the Department of Orthopaedics, Faculty of Medicine, Ramathibodi hospital, Mahidol University for all of the kindly help and permission to carry out this study. Conflict of interest conflict of interest.
All of the authors declare that they have no
References 1. Silber JS, Flynn JM, Koffler KM, Dormans JP, Drummond DS. Analysis of the cause, classification, and associated injuries of 166 consecutive pediatric pelvic fractures. J Pediatr Orthop. 2001;21:446–50. 2. Grisoni N, Connor S, Marsh E, Thompson GH, Cooperman DR, Blakemore LC. Pelvic fractures in a pediatric level I trauma center. J Orthop Trauma. 2002;16:458–63. 3. Rieger H, Brug E. Fractures of the pelvis in children. Clin Orthop Relat Res. 1997;336:226–39. 4. Hargitai E, Szita J, Doczi J, Renner A. Unstable pelvic fractures in children. Acta Chir Hung. 1998;37:77–83. 5. Smith W, Shurnas P, Morgan S, Agudelo J, Luszko G, Knox EC, Georgopoulos G. Clinical outcomes of unstable pelvic fractures in skeletally immature patients. J Bone Joint Surg Am. 2005;87:2423–31. 6. Schwarz N, Posch E, Mayr J, Fischmeister FM, Schwarz AF, Ohner T. Long-term results of unstable pelvic ring fractures in children. Injury. 1998;29:431–3. 7. Karunakar MA, Goulet JA, Mueller KL, Bedi A, Le TT. Operative treatment of unstable pediatric pelvis and acetabular fractures. J Pediatr Orthop. 2005;25:34–8. 8. Oransky M, Arduini M, Tortora M, Zoppi AR. Surgical treatment of unstable pelvic fracture in children: long-term results. Injury. 2010;41:1140–4. 9. McLaren AC, Rorabeck CH, Halpenny J. Long-term pain and disability in relation to residual deformity after displaced pelvic ring fractures. Can J Surg. 1990;33:492–4. 10. Bryan WJ, Tullos HS. Pediatric pelvic fractures: review of 52 patients. J Trauma. 1979;19:799–805. 11. McDonald GA. Pelvic disruptions in children. Clin Orthop Relat Res. 1980;151:130–4. 12. Smith WR, Oakley M, Morgan SJ. Pediatric pelvic fractures. J Pediatr Orthop. 2004;24:130–5. 13. Torode I, Zieg D. Pelvic fractures in children. J Pediatr Orthop. 1985;5:76–84. 14. Tile M. Acute pelvic fractures: I. Causation and classification. J Am Acad Orthop Surg. 1996;4:143–51. 15. Laohacharoensombat W, Jaovisidha S, Wajanavisit W, Suppaphol S. Apical derotation in the treatment of idiopathic scoliosis. J Med Assoc Thailand. 2005;88(Suppl 5):S58–64. 16. Keorochana G, Tawonsawatruk T, Laohachareonsombat W, Wajanavisit W, Jaovisidha S. The results of decompression and instrumented fusion with pedicular screw plate system in degenerative
Bilateral pediatric pelvic fracture
17.
18.
19.
20. 21.
lumbar scoliosis patients with spinal stenosis: a prospective observational study. J Med Assoc Thailand. 2010;93:457–61. Chanplakorn P, Chanplakorn N, Pongtippan A, Jaovisidha S, Laohacharoensombat W. Recurrent epithelioid sarcoma in the thoracic spine successfully treated with multilevel total en bloc spondylectomy. Eur Spine J. 2011;20(Suppl 2):S302–8. Chanplakorn P, Chanplakorn N, Kraiwattanapong C, Wajanavisit W, Laohacharoensombat W. Treatment of acute tuberculous spondylitis by the spinal shortening osteotomy: a technical notes and case illustrations. Asian Spine J. 2011;5:237–44. Chanplakorn P, Wajanavisit W, Laohacharoensombat W. Apical derotation for deformity correction in adolescent idiopathic scoliosis using the pedicle screw-plate spinal system: surgical technique and results. Tech Orthop. 2011;26:203–11. doi:10.1097/ BTO.0b013e31822e2ad4. Garvin KL, McCarthy RE, Barnes CL, Dodge BM. Pediatric pelvic ring fractures. J Pediatr Orthop. 1990;10:577–82. Heeg M, Klasen HJ. Long-term outcome of sacroiliac disruptions in children. J Pediatr Orthop. 1997;17:337–41.
22. Holden CP, Holman J, Herman MJ. Pediatric pelvic fractures. J Am Acad Orthop Surg. 2007;15:172–7. 23. Musemeche CA, Fischer RP, Cotler HB, Andrassy RJ. Selective management of pediatric pelvic fractures: a conservative approach. J Pediatr Surg. 1987;22:538–40. 24. Nierenberg G, Volpin G, Bialik V, Stein H. Pelvic fractures in children: a follow-up in 20 children treated conservatively. J Pediatr Orthop B. 1992;1:140–2. 25. Blasier RD, McAtee J, White R, Mitchell DT. Disruption of the pelvic ring in pediatric patients. Clin Orthop Relat Res. 2000;376:87–95. 26. Watts HG. Fractures of the pelvis in children. Orthop Clin North Am. 1976;7:615–24. 27. Heeg M, Klasen HJ, Visser JD. Acetabular fractures in children and adolescents. J Bone Joint Surg Br. 1989;71:418–21. 28. Matta JM, Saucedo T. Internal fixation of pelvic ring fractures. Clin Orthop Relat Res. 1989;242:83–97.
123
CASE REPORT
Modification of spinal pedicle screw-plate fixation for bilateral pediatric pelvic ring injury in 2-year-old girl Paphon Sa-ngasoongsong • Norachart Sirisreetreerux • Pongsthorn Chanplakorn • Patarawan Woratanarat • Chanyut Suphachatwong • Pornchai Mulpruek
Received: 18 October 2013 / Accepted: 20 December 2013 Ó The Japanese Orthopaedic Association 2014
Background Unstable pelvic fractures in children are an uncommon injury and are typically associated with high-energy trauma, such as an automobile accident or motor vehiclepedestrian injury [1–3]. Results from recent studies concluded that these unstable injuries needed to be treated with operative management [4–9], to achieve as near anatomical reduction as possible, with stable fixation to prevent longterm poor outcomes following non-operative treatment, such as residual pain, limb length discrepancy and scoliosis [10, 11]. Nevertheless, to date, there is still no consensus treatment option for surgical management in pediatric pelvic fracture, especially in very young children with displaced sacroiliac (SI) fracture-dislocation or bilateral SI joint injury. Traditional surgical fixation methods of SI joint disruptions, such as SI screw and anterior retroperitoneal SI plate, have several limitations because of the small bony anatomy in children, which requires an experienced surgeon and advanced imaging techniques. Moreover, there are still possible catastrophic intraoperative complications such as extensive blood loss, neurovascular injury, and implant jam due to the small bony architecture [12]. Therefore, in this present study, the authors aimed to introduce a new alternative surgical fixation procedure by modifying a spinal pedicle screw-plate (PSP) system to
P. Sa-ngasoongsong N. Sirisreetreerux P. Chanplakorn P. Woratanarat C. Suphachatwong P. Mulpruek (&) Department of Orthopedics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270, Rama VI Road, Ratchathewi, Bangkok 10400, Thailand e-mail: [email protected] P. Sa-ngasoongsong e-mail: [email protected]
treat a complex bilateral unstable SI joint fracture-dislocation in a very young pediatric patient with a minimally invasive technique, and to report the mid-term result.
Case report Case presentation A 2-year-old girl sustained a crush injury on her pelvis and right leg in a pedestrian-vehicle accident, which was caused by a six-wheeled truck running over her lower trunk. She was initially sent to a nearby hospital for emergency treatment. The primary survey showed good consciousness but she was in a state of shock, with positive tenderness and marked swelling on her pelvis. She had initially been treated with emergency endotracheal intubation, fluid resuscitation and pelvic wrapping. The initial radiographs and emergent computed tomography (CT) were taken, after achieving a stable hemodynamic status, and showed right SI fracture-dislocation, left SI joint dislocation, and left pubic rami fractures (Torode and Zieg classification type IV [13], and AO/OTA classification type C2 [14]) without other internal organ injury (Fig. 1). The diagnosis was open and bilateral unstable pelvic fracture with perineal and anal tear, left sciatic nerve injury, multiple deep pelvic lacerated wounds, and skin loss on right leg. Therefore, she was treated by emergency debridement with anterior pelvic external fixator, diverting colostomy, and wound debridement. Due to the severity of injuries, she was referred to our hospital on the 2nd day after injury for definitive treatment. On admission, the patient was in a stable condition but was still intubated and required a mechanical ventilator for respiratory support. Serial wound debridement was
123
P. Sa-ngasoongsong et al.
Fig. 1 Initial radiograph and computerized tomogram (CT) images under pelvic wrapping; portable pelvic radiograph after emergent urethrogram (a) showed displaced pelvic ring fractures on both sides (arrows). Axial CT (b) and three-dimensional CT images (c) further
demonstrated left sacroiliac (SI) joint dislocation (asterisk), right sacroiliac (SI) fracture-dislocation (thick arrow) and left pubic rami fracture (thin arrow) without obvious triradiate cartilage injury
Fig. 2 Postoperative radiographs after external fixator application; pelvic anteroposterior (a), inlet (b), and outlet (c) views revealed unstable bilateral posterior pelvic ring injury with asymmetrical deformity and 6-cm anterior pubic symphyseal widening (double head arrow) which could not be controlled with an anterior external fixator
performed to prevent infection. Intra-operative findings showed unstable and displaced pelvic fracture-dislocation on bilateral sides and an anterior external fixator was unable to achieve stability and reduce the fracture anatomically, as shown in postoperative radiographs (Fig. 2). Unfortunately, external stabilization with a pelvic C-clamp was considered impossible in this case because of the risk of intra-pelvic pin penetration from the transiliac fracturedislocation on the right side. Additionally, the application of a relatively large pin in a very small pelvis would increase the risk of damaging other vital structures; such as the sciatic nerve or triradiate cartilage. On the 9th day after
123
injury and after three debridements, the patient’s condition was improved and all wounds had no sign of infection. Preoperative planning for definitive treatment of the pelvic fracture was then discussed in detail. The goals of treatment in this patient were the same as for unstable pelvic fracture treatment: to create a symmetrical pelvis with stable fixation and to avoid early and long-term complications of surgical fixation [5–9]. Generally, the popular surgical fixation methods for posterior pelvic ring injury in children are SI screw and anterior retroperitoneal SI plate. However, these options had several limitations in this patient. SI screw insertion required surgical expertise and
Bilateral pediatric pelvic fracture
advanced imaging techniques, especially in this toddler patient with a very small sacral corridor and who had bilateral SI joint disruption. Moreover, using bilateral SI screws could be more difficult due to risk of implant jam. An anterior retroperitoneal SI plate was also not a good option due to needing extensive exposure, resulting increased blood loss, risk of L5 nerve root damage, and risk of infection from other pelvic wounds, especially from the colostomy site [12]. Therefore, we designed a new fixation method, modifying the spinal pedicle screw-plate (PSP) system to stabilize this bilateral posterior pelvic ring injury in this very young patient. Surgical techniques After general anesthesia, the patient was placed in a prone position, on a radiolucent table, with bolster support on her chest and proximal thigh to prevent pressure on the abdomen and both iliac crests (Fig. 3a). Anterior external fixator clamps were also released before starting the operation to allow easier fracture reduction. Surgery was performed by using a bilateral posterior SI joint approach and the PSP system (T.K.S. Metal Works Co. Ltd, Bangkok, Thailand). The PSP system is a spinal fixation system which was conventionally designed for treating varieties of spinal diseases [15–18]. The system is a constrained lock design
Fig. 3 Intraoperative images and three-dimensional animation model. Intraoperative pictures show (a) the surgical setting in prone position, and surgical incision (b) as bilateral vertical incisions with pedicle screw insertions (arrows) at 1-cm below the posterior superior iliac spine (PSIS). Pelvic model pictures before (c) and after plate
using a thread plate and an identical thread washer, locking together by a compressive nut [19]. A 5-cm longitudinal incision over the posterior superior iliac spine (PSIS) was created on both sides, and then the superficial dissection preceded down to PSIS with a full thickness flap for preserving the blood supply. The pedicle screw entry point was designed to be at 1 cm below the PSIS in order to prevent prominence of the screw head and plate (Fig. 3b). Moreover, due to the locking screw head system, this same anatomical entry point would assist in the reduction of the sacroiliac fracture-dislocation or dislocation of both sides at the same level after applying the spinal plate (Fig. 3c–e). After the entry point was made, using a little curettage, the screw tract was created in an anteriorly forward direction, into the supra-acetabular region between the outer and inner cortex of the ilium. After measuring the depth and checking for perforation with blunt smooth K-wire, a 40-mm-long, 6.5-mm-diameter pedicle screw was inserted on each side. Then a subcutaneous tunnel between those two screws was developed above the fascia layer of the lower sacrum, and used for inserting a precontouring 90-mm spinal plate through this tunnel. One pedicle screw was initially locked to allow easier fracture control. After that, the closed reduction of the posterior pelvic ring was done with manual compression on both posterior iliac crests, leg traction, and the constraining effect from the
application (d), demonstrate the reduction (thick arrows) by the constraint of the pedicle screw plate (PSP) system (thin arrow). Fluoroscopic image (e) demonstrates the nearly anatomical reduction of the pelvic ring after applying the spinal plate
123
P. Sa-ngasoongsong et al.
locking system of the contralateral screw against the precontouring plate, as seen in Fig. 3c–e). Finally, pelvic fracture alignment and stability was tested under a fluoroscope, and demonstrated that the fracture was stable enough without needing anterior support. Therefore, the anterior external fixator was removed at the end of the operation and wound closure was performed without using a drain. The total operative time was 45 min and minimal blood loss was encountered. Postoperative care and rehabilitation Postoperatively, the patient was allowed to start progressive ambulation from bed rest to sitting rehabilitation during the first 3 months, and this was followed by progressive weight bearing, as tolerated, with a gait aid. She had stayed in the hospital for 4 weeks due wound care and was discharged without complication. The fractures healed uneventfully, as shown in postoperative follow-up images (Fig. 4). Implant removal was done at 6 months, and she
Fig. 4 Postoperative radiographs and CT scan images at 4 weeks; postoperative pelvic anteroposterior (a), inlet (b), and outlet (c) views reveal nearly anatomical reduction with symmetrical pelvic ring. The axial CT images at the S1 level (d), right pedicle screw level (e), left
123
could walk independently without pain at 9 months. The left sciatic nerve injury was fully recovered at 1 year postoperatively. At the latest follow-up period (18 months), she had no sign of serious complications such as infection, leg length discrepancy, or recurrent pelvic instability (Fig. 5). This study has been reviewed and approved by our Institutional Board, based on the Declaration of Helsinki. The patient and her family were informed that data from the case would be submitted for publication, and consent was given by the patient’s parents.
Discussion Pediatric pelvic fractures are a relatively rare condition, and are usually associated with multiple organ injuries from high-energy trauma. The most common causes are motor vehicle accident, pedestrian-automobile collision, and falls from height. Due to its severity, up to 15 % of
pedicle screw level (f) and coronal CT images (g) demonstrated anatomical reduction of sacroiliac joint with appropriate screw position
Bilateral pediatric pelvic fracture
Fig. 5 Postoperative compared radiographs at 6 months and 18 months after implant removal, and clinical compared wound pictures at 2 weeks and 6 months; pelvic anteroposterior (a), inlet (b) and outlet (c) films showed fracture union and good bone remodeling in
nearly symmetrical pelvis without sign of instability or leg length discrepancy. Clinical pictures (d) revealed no postoperative wound problem
these patients die, and 30 % of those who survive are disabled, with a long-term poor outcome [3, 6, 20, 21]. Generally, the decision as to how to treat pelvic fractures in children is based on the patient’s age, fracture classification, stability of the pelvic ring, extent of concomitant injuries, and hemodynamic stability [22]. Historically, these fractures had been treated with conservative treatment, such as pelvic sling and traction, due to the belief in the great ability of fracture healing and remodeling in children, and risks of neurovascular and triradiate cartilage injury from surgery [13, 23–26]. However, multiple longterm follow-up studies showed that using these methods in unstable pelvic and/or acetabular fractures would result in significant malreduction and unsatisfactory long-term complications, such as residual pain, limp, and scoliosis [9–11, 27]. Moreover, several recent studies, which performed operative management in unstable pelvic and acetabular fractures to achieve anatomical or near-anatomical reduction, have demonstrated a successful outcome with low incidence of complications [7, 8]. Therefore, it has been suggested that the treatment strategy of unstable pelvic fractures in children should be the same as in adults. Nevertheless, to our knowledge, there is still no consensus in surgical fixation methods in this unstable pediatric pelvic fracture, especially in very young children or in bilateral SI joint disruption.
Traditionally, the surgical fixation options in unstable pediatric pelvic fractures include anterior external fixator, SI screw, and anterior retroperitoneal SI plate; however, there are several limitations in using these methods due to their strict prerequisites and risk of specific complications [12]. Although an anterior external fixator may help in fracture stabilization in the early phase, its application cannot provide posterior ring stability, and the resulting pelvic asymmetry following this method has been shown to be greater than from nonoperative treatment [28]. SI screw application is a very demanding procedure, requiring surgical expertise and CT guidance due to a narrow safe sacral corridor in a small pediatric pelvis. Furthermore, insertion of this screw in some certain circumstances, such as in a very young patient, a patient with pelvic dysmorphism, or patients with displaced fractures and bilateral injury, would result in a greater risk of iatrogenic complications such as neurovascular injury and implant jam. An anterior retroperitoneal SI plate needs extensive exposure, resulting in greater blood loss and risk of damage of the L5 nerve root [12]. Application of the pedicle screw-plate (PSP) system in pediatric pelvic fracture, as we have introduced in this study, has many advantages. First, the surgical approach in this study is a minimally invasive approach. We just used a bilateral mini-incision posterior SI approach, with only
123
P. Sa-ngasoongsong et al.
superficial dissection at PSIS to insert the pedicle screws into the iliac bone. These screws could then be used as joy sticks (so as not to open the SI joint, and avoiding direct manipulation), after which a subcutaneous tunnel was created between the screws to insert the plate. This surgical technique results in a small amount of blood loss and lessens the risk of iatrogenic neurovascular injury. Moreover, this posterior approach is a safer approach in reducing surgical contamination in patients with an anterior pelvic wound, supra-pubic catheter, or colostomy. Secondly, the fracture stability from PSP application should be much higher than the stability from SI screw application due to the larger screws (standard pedicle screw) inserted into good quality bone in the supra-acetabular area, and the angular stability from the locking system. Therefore, the resulting fracture stability after PSP application should be sufficient to control the pelvic ring fracture without need of anterior support, as seen in Figs. 3, 4. Thirdly, several closed reduction techniques could be used with this fixation method for external compression and leg traction, manipulation from the anterior iliac crest pin, and the constraining effect from the pre-contour plate application (Fig. 3). Additionally, screw insertion in the same anatomical landmark would assist the reduction in the case of superior migration of one hemipelvis. Finally, the risk of neurovascular or triradiate cartilage injury from this technique is low due to the screw being fixed in one bone (iliac bone), the ability to check the screw tract before screw insertion, and the positioning of the screw is not close to the lumbosacral plexus, triradiate cartilage or vital structures in the pelvic cavity (Fig. 4). However, this approach also has some limitations. First, as in the other approach, the incision area on the buttock should not have a contaminated wound. Secondly, although this technique is less surgically demanding than other surgical fixation methods on the posterior pelvic ring, the authors recommend that the surgeon always uses an intraoperative fluoroscope to confirm the screw placement and the quality of fracture reduction. Thirdly, due to the need for surgical setting in the prone position, this approach should be avoided or used with caution in the patients who have concomitant internal organ injury, especially in the acute phase. Lastly, the plate should be placed at the lower sacrum level to avoid skin complications, and the implant should be removed after the fracture has healed (usually at 5–6 months after surgery) in order to allow normal growth of the pelvic bone.
Conclusion Application of a pedicle screw-plate (PSP) system with a minimally invasive posterior approach is a possible
123
surgical option for definitive fixation in unstable pediatric pelvic fractures. We believe that this method is a safe and very useful technique, especially in very young children and those having bilateral injury. However, pre-operative planning, correct surgical technique, accurate direction of screw placement, and intraoperative fluoroscope imaging are needed. Acknowledgments The authors are thankful to Professor Wichien Laohachareonsombat, M.D., who kindly helped as a senior consultant, and thank the Department of Orthopaedics, Faculty of Medicine, Ramathibodi hospital, Mahidol University for all of the kindly help and permission to carry out this study. Conflict of interest conflict of interest.
All of the authors declare that they have no
References 1. Silber JS, Flynn JM, Koffler KM, Dormans JP, Drummond DS. Analysis of the cause, classification, and associated injuries of 166 consecutive pediatric pelvic fractures. J Pediatr Orthop. 2001;21:446–50. 2. Grisoni N, Connor S, Marsh E, Thompson GH, Cooperman DR, Blakemore LC. Pelvic fractures in a pediatric level I trauma center. J Orthop Trauma. 2002;16:458–63. 3. Rieger H, Brug E. Fractures of the pelvis in children. Clin Orthop Relat Res. 1997;336:226–39. 4. Hargitai E, Szita J, Doczi J, Renner A. Unstable pelvic fractures in children. Acta Chir Hung. 1998;37:77–83. 5. Smith W, Shurnas P, Morgan S, Agudelo J, Luszko G, Knox EC, Georgopoulos G. Clinical outcomes of unstable pelvic fractures in skeletally immature patients. J Bone Joint Surg Am. 2005;87:2423–31. 6. Schwarz N, Posch E, Mayr J, Fischmeister FM, Schwarz AF, Ohner T. Long-term results of unstable pelvic ring fractures in children. Injury. 1998;29:431–3. 7. Karunakar MA, Goulet JA, Mueller KL, Bedi A, Le TT. Operative treatment of unstable pediatric pelvis and acetabular fractures. J Pediatr Orthop. 2005;25:34–8. 8. Oransky M, Arduini M, Tortora M, Zoppi AR. Surgical treatment of unstable pelvic fracture in children: long-term results. Injury. 2010;41:1140–4. 9. McLaren AC, Rorabeck CH, Halpenny J. Long-term pain and disability in relation to residual deformity after displaced pelvic ring fractures. Can J Surg. 1990;33:492–4. 10. Bryan WJ, Tullos HS. Pediatric pelvic fractures: review of 52 patients. J Trauma. 1979;19:799–805. 11. McDonald GA. Pelvic disruptions in children. Clin Orthop Relat Res. 1980;151:130–4. 12. Smith WR, Oakley M, Morgan SJ. Pediatric pelvic fractures. J Pediatr Orthop. 2004;24:130–5. 13. Torode I, Zieg D. Pelvic fractures in children. J Pediatr Orthop. 1985;5:76–84. 14. Tile M. Acute pelvic fractures: I. Causation and classification. J Am Acad Orthop Surg. 1996;4:143–51. 15. Laohacharoensombat W, Jaovisidha S, Wajanavisit W, Suppaphol S. Apical derotation in the treatment of idiopathic scoliosis. J Med Assoc Thailand. 2005;88(Suppl 5):S58–64. 16. Keorochana G, Tawonsawatruk T, Laohachareonsombat W, Wajanavisit W, Jaovisidha S. The results of decompression and instrumented fusion with pedicular screw plate system in degenerative
Bilateral pediatric pelvic fracture
17.
18.
19.
20. 21.
lumbar scoliosis patients with spinal stenosis: a prospective observational study. J Med Assoc Thailand. 2010;93:457–61. Chanplakorn P, Chanplakorn N, Pongtippan A, Jaovisidha S, Laohacharoensombat W. Recurrent epithelioid sarcoma in the thoracic spine successfully treated with multilevel total en bloc spondylectomy. Eur Spine J. 2011;20(Suppl 2):S302–8. Chanplakorn P, Chanplakorn N, Kraiwattanapong C, Wajanavisit W, Laohacharoensombat W. Treatment of acute tuberculous spondylitis by the spinal shortening osteotomy: a technical notes and case illustrations. Asian Spine J. 2011;5:237–44. Chanplakorn P, Wajanavisit W, Laohacharoensombat W. Apical derotation for deformity correction in adolescent idiopathic scoliosis using the pedicle screw-plate spinal system: surgical technique and results. Tech Orthop. 2011;26:203–11. doi:10.1097/ BTO.0b013e31822e2ad4. Garvin KL, McCarthy RE, Barnes CL, Dodge BM. Pediatric pelvic ring fractures. J Pediatr Orthop. 1990;10:577–82. Heeg M, Klasen HJ. Long-term outcome of sacroiliac disruptions in children. J Pediatr Orthop. 1997;17:337–41.
22. Holden CP, Holman J, Herman MJ. Pediatric pelvic fractures. J Am Acad Orthop Surg. 2007;15:172–7. 23. Musemeche CA, Fischer RP, Cotler HB, Andrassy RJ. Selective management of pediatric pelvic fractures: a conservative approach. J Pediatr Surg. 1987;22:538–40. 24. Nierenberg G, Volpin G, Bialik V, Stein H. Pelvic fractures in children: a follow-up in 20 children treated conservatively. J Pediatr Orthop B. 1992;1:140–2. 25. Blasier RD, McAtee J, White R, Mitchell DT. Disruption of the pelvic ring in pediatric patients. Clin Orthop Relat Res. 2000;376:87–95. 26. Watts HG. Fractures of the pelvis in children. Orthop Clin North Am. 1976;7:615–24. 27. Heeg M, Klasen HJ, Visser JD. Acetabular fractures in children and adolescents. J Bone Joint Surg Br. 1989;71:418–21. 28. Matta JM, Saucedo T. Internal fixation of pelvic ring fractures. Clin Orthop Relat Res. 1989;242:83–97.
123
