- Email: [email protected]
Management of lumbosacropelvic fracture-dislocation using lumbo-iliac internal fixation
Injury, Int. J. Care Injured 43 (2012) 452–457
Contents lists available at SciVerse ScienceDirect
Injury journal homepage: www.elsevier.com/locate/injury
Management of lumbosacropelvic fracture-dislocation using lumbo-iliac internal fixation Hai-Chun Liu a, Yun-zhen Chen a, Xi-Guang Sang b,*, Lei Qi a a b
Department of Orthopedic and Trauma Surgery, Qilu Hospital, Shandong University, Jinan, Shandong 250012, China Department of Traumatic Emergency, Qilu Hospital, Shandong University, Jinan, Shandong 250012, China
A R T I C L E I N F O
A B S T R A C T
Article history: Accepted 25 August 2011
Objective: Traumatic lumbosacropelvic fracture-dislocation is a rare but potentially serious injury. Conventional methods like lumbosacral fixation used to treat such injuries often result in suboptimal outcome secondary to complications like pseudoarthroses, sagittal imbalance and hardware failure. In this study, we retrospectively analysed the clinical features and management for this trauma using lumbo-iliac fixation. Methods: Eight patients (6 male, 2 female; 21–52 years old, mean: 38.4) with traumatic lumbosacropelvic fracture-dislocation were surgically managed by lumbo-iliac internal fixation after lumbosacral decompression. Patients were followed up for 24–40 months (mean: 31.6). American Spine Injury Association (ASIA) scores were measured before surgery and at the last follow-up, and statistically analysed. Results: After surgery, all patients experienced improved sensory and motor performance. Six patients showed recovery of bowel and bladder functions. Immediately after lumbo-iliac fixation, all patients could turn in bed without assistance. Lumbosacral alignment was restored immediately after surgery and no dislocation was observed during follow-up. Radiography indicated excellent integration between the autograft and the vertebrae. After surgery, no patient experienced neurological deterioration. Conclusion: Our experience with these cases suggests that early surgical decompression and posterior lumbo-iliac internal fixation can effectively restore spinal alignment, stabilise the spine, and improve neurological symptoms for this complex trauma. ß 2011 Elsevier Ltd. All rights reserved.
Keywords: Lumbosacropelvic fracture Internal fixation Complex trauma
Introduction Traumatic lumbosacropelvic dislocation is a severe high-energy trauma that is usually combined with extensive soft tissue damage, haemorrhagic shock, and injuries to multiple organs.1 Therefore, it is associated with a high mortality. Currently there have been only a few case reports on lumbosacral dislocation, mainly pertaining to fracture-dislocation of the lumbosacral and sacroiliac joints, and sacral fracture combined with bilateral sacroiliac dislocation.2–6 Simultaneous damage to the pelvis and the lumbosacral and sacroiliac joints (termed here as traumatic lumbosacropelvic fracture-dislocation) is a rare but severe mode of trauma and its course, prognosis, and management has not been extensively investigated. The management of this condition is unique because of its difficult anatomical location, unique biomechanical forces acting in this region and poor sacral bone quality. A lumbosacro-
pelvic fracture-dislocation often affects the cauda equina and impairs lower extremity motor, bowel and bladder function. Some of the early case series suggested use of conservative (nonsurgical) treatment because of the difficulties associated with surgical procedures.7,8 The nonsurgical approach however did not provide optimal results. There were patients who did not improve neurologically and developed instability and deformities in the lumbosacral region, and some developed neurological deterioration.2,4,25,26 Open reduction and subsequent stabilisation is the standard of care, conservative procedures are reserved to very selected cases only.5,17,34 Therefore, these patients must be carefully observed and prepared for surgical treatment especially those with neurodeficit.32,33 Surgery is best done early as delay may result in fibrous malunion of the fractured bones, increasing the difficulty of surgical reduction and fixation, and the risk of iatrogenic injury to the cauda equina during manipulation.21,23,27– 31
* Corresponding author. Tel.: +86 13808939226; fax: +86 13808939226. E-mail addresses: [email protected] (H.-C. Liu), [email protected] (X.-G. Sang). 0020–1383/$ – see front matter ß 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.injury.2011.08.036
Surgical management of lumbosacropelvic dislocation-fracture requires an appropriate fixation technique. We report here management of lumbosacroiliac fracture-dislocation by a new lumbo-iliac fixation. In this study, we retrospectively analyse the
H.-C. Liu et al. / Injury, Int. J. Care Injured 43 (2012) 452–457
treatment of eight cases of lumbosacroiliac fracture-dislocation by this technique in our hospital.
453
procedures. In cases of dislocation combined with lumbar fractures, magnetic resonance imaging (MRI) was used to reveal the conditions of spinal cord compression.
Materials and methods Surgical operation Patients Eight patients (6 males, 2 females, 21–52 years old, mean: 38.4 years) with traumatic lumbosacroiliac fracture-dislocation were admitted to our hospital between May/2/2006 and November/1/ 2010 (Table 1). Three patients presented with L5–S1 dislocation combined with sacroiliac joint dislocation. The other five patients presented with sacral fracture-dislocation combined with sacroiliac joint dislocation. Moreover, in all patients the trauma was combined with anterior pelvic ring injury and other fractures. At the time of admission, seven patients were in a shock state and four patients had severe thoracoabdominal traumas. Four patients were given mechanical ventilation due to breathing difficulty. All patients had impaired lower limb mobility (extension-flexion dysfunction of the affected foot/ankle) and bowel and bladder function (difficult urination and defecation). The level of neurological injury in each patient was evaluated by the American Spinal Injury Association (ASIA) scoring system.14 Imaging All patients underwent emergency care immediately after admission. After recovering stable vital signs, they were examined by radiography and computed tomography (CT) to assess their injuries. All patients were found to have posterior pelvic ring damages, including one patient with three zone-I sacral fractures, three patients with zone-II fractures, and two patients with zoneIII fractures. Two patients had complete sacroiliac joint dislocations, and the other six patients had complete L5/S1 dislocationseparations. All patients had fractures of the superior articular process of S1, including three patients with free sacral fragments (including the superior articular process of S1), three patients with L5 isthmus fractures, one patient with a combined L1 fracture, and one patient with a combined L4 fracture. All patients were found to have anterior pelvic ring damages, including two patients with unilateral pubic ramus fractures, four patients with bilateral fractures of the pubic rami, two patients with pubic symphysis separations of >2.5 cm, and one patient with combined acetabular fracture-dislocation. Spiral CT and subsequent three-dimensional reconstruction were used to reveal the fracture at the articular process and vertebral isthmus, and free sacral fragments including the superior articular process of S1. The imaging information was used in the evaluation of trauma conditions and planning of surgical
Preoperative treatment Each patient was examined for general conditions and then was cared for in an ICU until resuscitation and target physiologic parameters were reached. After the patient’s condition became stable, the indication for surgical treatment was determined and the benefit of surgical treatment assessed. In these patients, the interval between trauma and definitive surgery ranged from 4 to 11 days (mean 7.2 days). Definitive surgery The patient was placed in a supine position and the anterior pelvic ring injury was treated, by open reduction and plate fixation. In cases of difficult reduction, an ilioinguinal incision was made and the dislocated sacroiliac joint was exposed, debrided and reduced. Then, the patient was switched to a prone position and underwent lumbo-iliac fixation, either by posterior midline incision or short posterior midline incision combined with bilateral arc incision to the posterior superior iliac spines (Fig. 1). The second approach was later found to be superior in several respects. It could directly expose the posterior superior iliac spine and the sacroiliac joint, avoid overstretch of the skin, suspend the sacral skin, reduce stimulation to the skin in cases of combined severe sacral fracture and sacral skin damage, theoretically increase the opportunity of fracture union and reduce occurrence of infection. The lumbar and sacral vertebrae were exposed and both were partially resected to allow decompression of the vertebral canal. Bone mass protruding into the canal was reduced or resected, and any dural sac rupture was repaired to prevent post-operative cerebrospinal fluid leakage and infection. Pedicle screws were inserted into L4 and L5. If S1 was intact, a pedicle screw was inserted into S1 in some cases. Rods were attached and distracted to reduce the dislocated vertebrae. The pedicle screw at S1 was omitted if it was too severely fractured to accept a pedicle screw. The superior articular process of S1 was resected if it was found to prevent the reduction. Before inserting the sacral screw, the posterior superior iliac spine (PSIS) was exposed and then a 1 cm 4 cm bone chip was removed from the inferior part of the PSIS to create a smooth bony bed. Perpendicular to this bony bed, a sacral screw was inserted into the posterior column of the ilium. A titanium link rod was bent into a desirable profile, attached to the screws, and fastened. The vertical dislocation of the ilium was reduced by distraction of the rod attached to the lumbar spine. The
Table 1 A summary of patient conditions, operations, and outcomes. Patient no.
Sex
Age (years)
1 2 3 4
Male Male Female Male
28 31 21 51
5 6 7
Female Male Male
47 38 52
8
Male
39
Cause of trauma
Motorcycle accident Impact Fall from height Impact due to traffic accident Fall from height Fall from height Crush under tricycle wheels Impact due to traffic accident
ISS score on admission
Trauma– surgery interval (days)
Surgery duration (h)
Bleeding volume (mL)
ASIA score before surgery
ASIA score at latest follow-up
Sensory
Motor
Sensory
Motor
Follow-up time (months)
24 29 21 34
8 10 7 15
4.3 4.5 3.7 4.5
1200 1450 1350 1700
40 32 38 33
38 28 36 27
68 45 68 44
46 36 43 36
32 27 24 33
45 24 35
21 5 14
4 3.5 5.5
1250 800 2800
30 46 32
22 40 28
37 66 38
27 48 35
25 40 33
33
10
5.3
2300
35
36
58
42
39
454
H.-C. Liu et al. / Injury, Int. J. Care Injured 43 (2012) 452–457
Results
Fig. 1. A photograph showing incisions planned for internal lumbosacroiliac fixation.
horizontal dislocation of the ilium was reduced by compression of the horizontal connecting rod. The bone mass removed from the ilium was implanted into the intervertebral space for fusion. For patients with sacral fracture displacement, we debride the soft tissue between fracture fragments and decompress sacral neuroforamen, and then place tiny bone particles into the broken ends of fractured bone and perform compression to receive fracture healing. For patients with sacroiliac joint dislocation, we debride the residual ligament rupture, place tiny bone particles into dislocated joint and perform compression for sacroiliac joint fusion (Figs. 2 and 3). The whole procedure takes 3.5–5.5 h (mean 4.4 h) and the intraoperative bleeding volume ranged from 800 to 2800 mL (mean 1606 mL). The patient was instructed to stay in bed for 3–5 weeks and to participate in lower limb/joint functional exercise during the bed stay. Then, the patient was allowed to resume off-bed activities whilst wearing a waist brace. The patient underwent regular rehabilitation (hyperbaric oxygen treatment, and electric stimulation treatment) and neurotrophic drug treatment to accelerate the recovery of neurologic functions. Follow-up Patients were followed-up for 24–40 months (mean 31.6 months). They were evaluated using radiography for the status of fracture healing, spinal alignment, and stability at five time points: at 6 weeks, and 3, 6, 12, and 24 months after surgery. Radiographs were taken at dynamic postures when necessary to check for screw lessening or fracture. Before surgery and at the last follow-up, the sensory and motor performances of each patient were evaluated according to the ASIA scoring scale; rectal and bladder functions were also examined. Statistical analyses ASIA scores were analysed by paired t-tests with SPSS 11.5 (SPSS, Chicago, IL, USA), and a P-value less than 0.05 was considered statistically significant.
There was no mortality as a result of the procedure. After surgery, both the sensory and motor scores (Table 2) increased significantly, but still remained below the scores in normal individuals. In general, a patient with more severe trauma was also observed to have less recovery. After surgery, six patients showed different degrees of recovery of bowel and bladder function with good control of urination and defecation. The other two patients continued to experience severe bowel and bladder dysfunction and lacked the ability to control urination and defecation. Immediately after lumbo-iliac fixation, all patients could turn in bed without assistance. Patients who recovered neurological functions relatively early were able to resume off-bed activities from 3 weeks after surgery. Pain resulting from nerve root compression reduced immediately after surgery. Lumbosacral alignment was restored immediately after surgery and no dislocation was observed during follow-up. Radiography indicated excellent integration between the autograft and the vertebrae. After surgery, no patient experienced neurological deterioration. One patient who underwent posterior midline incision experienced delayed incision healing, but the incision eventually healed after debridement and suturing. One patient showed cerebrospinal fluid leakage and was cured by pressure dressing. One patient developed infection, probably related to the open sacral fracture-dislocation, which was controlled by debridement and antimicrobial treatment. Six patients experienced muscle disuse atrophy and stiffness, and were successfully managed by exercise and physical therapy. One patient experienced skin damage due to contact pressure from the end of an iliac screw. The skin rupture subsequently healed.
Discussion The lumbosacral area has a unique anatomy and is subject to unusual stresses. For effective weight transmission it is essential that the stability and anatomy of the region be restored after fracture dislocation. From these cases, we found that lumbo-iliac fixation combined with vertebral canal decompression and fusion is an effective treatment for traumatic lumbosacroplevic fracturedislocation. In these patients, the operation significantly improved sensory and motor capability of the lower limbs and bowel and bladder function. There have been a number of case reports on lumbosacral and sacroiliac fracture-dislocation.2,15,16 Lumbosacral dislocation combined with sacroiliac fracture was observed in a few cases, and named inconsistently.1,3 Here, we propose a general concept of traumatic lumbosacropelvic dislocation, characterised by damage to the lumbosacropelvic region combined with simultaneous injuries to L5, the sacrum, sacroiliac joint, ilium, and the anterior pelvic ring. This trauma affects both the anteroposterior and lateral stability of the lumbosacropelvic structure. It substantially changes the biomechanical structure of the lumbar vertebrae, the sacrum and pelvis and results in a high degree of instability. In this complex trauma setting, the high instability presents a challenge to surgical correction. Simple sacroiliac dislocation (e.g., without lumbosacral damage) can be fixed by several techniques.9–11 such as the use of anterior sacroiliac plates, posterior sacral rods, or sacroiliac screws. Matta et al.12 found that the sacral rod can produce inferior fixation compared with anterior sacroiliac plates. However, percutaneous insertion of sacroiliac screws involves substantial higher risks if sacral abnormalities are present.1,10 Additionally, in cases of sacral fracture with vertical displacement, the sacroiliac screw is prone to loosening and may result in loss of reduction.13
H.-C. Liu et al. / Injury, Int. J. Care Injured 43 (2012) 452–457
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Fig. 2. Images showing the lumbosacropelvic trauma in a 56-year-old male patient resulting from a vehicle accident; (a and b) 3D reconstructed images revealing complete dislocation of the left ilium combined with multiple transverse process fractures and left-posterior displacement of lumbar vertebra; (c and d) X-radiographs after surgery showing excellent spinal and iliac alignment and correct placement of iliac and sacroiliac screws.
Moushine et al.20 suggested that surgical management for unstable lumbosacral fracture should purport to reconstruct the lumbosacral joint, restore the spine-pelvis alignment, and reach early load bearing. Because of the difficult conditions in lumbosacropelvic fracture-dislocation, none of sacroiliac screws, sacral rods and anterior plates can provide sufficient stability.18,19 The lumbo-iliac fixation performed in these patients is a modified Galveston technique,10 and it was found to be effective for this complex trauma. For traumatic lumbosacropelvic dislocation, the lumbo-iliac fixation allows the body gravity to be transferred through the titanium rod, iliac screw, the posterior of the ilium, and then directly to the acetabulum, hence bypassing the fractured sacrum to allow an effective decompression of the sacral canal, so the patients could bear load 24 h after surgery. Reduction of the dislocated sacrum or sacroiliac joint is critical for the success of the operation. After preoperative skeletal traction, the ilium is vertically reduced by distracting the connector between the iliac screw and the lumbar rod, and
horizontally reduced by applying pressure on the connector to force the ilia to laterally separate. If the condition permits, a sacroiliac screw may be used to improve the stability and facilitate the recovery of the biomechanical function of the lumbosacroiliac region. Matta12 suggested that in cases of combined damage of the posterior and anterior pelvic rings, fixation of the posterior ring is necessary; if a strong fixation of the posterior ring is available the anterior ring fixation may be omitted. Schildhauer21 believed that the anterior ring should be first fixed to provide stability and help the reduction of the posterior ring. Our experience with these patients also suggests that the anterior ring should be first fixed in case of large fracture-dislocation of the pubic rami or separation of the public symphysis. We performed anterior ring fixation in all patients to increase stability as well as reduce the stress associated with posterior fixation alone. Verlaan4 reported that damages to the lumbosacral plexus and the sacral nerve during traumatic lumbosacral dislocation are
H.-C. Liu et al. / Injury, Int. J. Care Injured 43 (2012) 452–457
456
Fig. 3. Images showing the trauma in a 48-year-old female patient resulting from a vehicle accident; (a) an axial CT before surgery revealing bilateral separation of the sacroiliac joints and comminuted fracture of the right sacrum; (b) a radiograph before surgery showing fracture-dislocation of the anterior pelvic ring; (c) a radiograph after surgery showing correct placement of iliac screws, connecting rods, and fixation plates; (d) a radiograph after surgery showing accurate placement of iliac screws into posterior columns of the ilia.
usually traction injuries. Under this injury mode, decompression can result in only limited recovery of neurological function but might impair spinal stability. Therefore, they believed that the primary purpose of surgical management should be restoring spinal stability, followed by recovery of neurological function. Chin et al.,22 however, observed in three cases that early decompression improved the neurological function, and identified the decompression time and the degree of spinal stenosis as major influential factors in neurological recovery. Patients with lumbosacral dislocation, particularly those undergoing a delayed surgical treatment, may develop traction injuries during reduction due to scar adhesion around the lumbosacral nerves. Therefore it is critical to check the spinal canal for any protruding disc tissue or bony mass before reduction. Our experience suggests that if neurological symptoms and clear imaging evidence of spinal compression are present beforehand, the canal should be decompressed during surgery, the adhesion be released, and a structure protruding into the spinal canal should be resected Table 2 Comparison of ASIA scores before surgery and at the last follow-up (mean standard deviation).
Sensory score Motor score
Before surgery
Latest follow-up
t-Value
P-value
35.75 5.31 31.88 6.42
53.00 13.47 39.13 6.90
5.24 16.00
0.0012 <0.0001
before reduction to prevent any nerve traction and facilitate neurological recovery. Most patients in this report showed clear recovery of neurological function and excellent lumbar-pelvic stability, which favoured early off-bed activity. The patients treated by lumbar-iliac fixation experienced relatively few complications. In comparison, an earlier study reported sacral fracture to have an infection rate of 16% and the rate of delayed healing to be 14%.23 Our approach on the subsequent five patients (a short incision at the posterior midline combined with bilateral arc incisions at the posterior superior iliac spines) was found to effectively prevent incision infection and delay healing, probably because it reduced secondary damage to the already-damaged sacral skin and prevented excessive skin traction. Compression of the skin by fixation instruments deserves concern. An early patient developed skin necrosis resulting from compression by the protruding fixation instrument. In our operations with the later patients, the bone at the screwing location was typically removed by approximately 1 cm to sink the screw head slightly below the posterior superior iliac spine. Like most studies, ours also fails to address and resolve certain issues. The use of unilateral lumbo-iliac fixation versus bilateral fixation has been widely debated. Tomilson et al.24 in their biomechanical study demonstrated a superior outcome with unilateral fixation, as compared to bilateral lumbo iliac fixation. In our studies we did both unilateral and bilateral fixation depending on the severity of trauma and the nature of the
H.-C. Liu et al. / Injury, Int. J. Care Injured 43 (2012) 452–457
expected instability, and we could not arrive at any conclusion regarding superiority of one over the other. We also used a different surgical approach in the later group and reached a conclusion vis-a`-vis superiority of the later approach that involved a small midline and tow accessory para-spinal incisions along the arch of iliac crest, but we did not give a statistical analysis and comparison between two surgical approach. Our studies also have obvious limitations, include generalisability (complex anatomy, high demanding technique, catastrophic complications), heterogeneous demographic characters and injuries of the enrolled cases, lack of a control group. Although the series reported here is small, we believe that it provides valuable information of a promising fixation technique for this complex trauma. In conclusion, our experience with these patients shows that preoperative planning and resuscitation following the principles of damage control surgery (DCS) are critical. Decompression of the spinal canal and internal lumbo-iliac fixation can effectively improve neurological function, stabilise fractures, restore spinal alignment, prevent deformity, favour early activities, and reduce complications. References 1. Vresilovic EJ, Mehta S, Placide R, Milam 4th RA. Traumatic spondylopelvic dissociation. A report of two cases. J Bone Joint Surg Am 2005;87:1098–103. 2. Cruz-Conde R, Rayo A, Rodriguez de Oya R, Berjano P, Ga´rate E. Acute traumatic lumbosacral dislocation treated by open reduction internal fixation and fusion. Spine (Phila Pa 1976) 2003;28:E51–3. 3. Bents RT, France JC, Glover JM, Kaylor KL. Traumatic spondylopelvic dissociation. A case report and literature review. Spine (Phila Pa 1976) 1996;21:1814–9. 4. Verlaan JJ, Oner FC, Dhert WJ, Verbout AJ. Traumatic lumbosacral dislocation: case report. Spine (Phila Pa 1976) 2001;26:1942–4. 5. Veras del Monte LM, Bago´ J. Traumatic lumbosacral dislocation. Spine (Phila Pa 1976) 2000;25(6):756–9. 6. Whitbeck Jr MG, Zwally 2nd HJ, Burgess AR. Innominosacral dissociation: mechanism of injury as a predictor of resuscitation requirements, morbidity, and mortality. J Orthop Trauma 1997;11:82–8. 7. Tile M. Pelvic ring fractures: should they be fixed? J Bone Joint Surg Br 1988;70:1–12. 8. Phelan ST, Jones DA, Bishay M. Conservative management of transverse fractures of the sacrum with neurological features: a report of four cases. J Bone Joint Surg Br 1991;73:969–71. 9. Kostuik JP, Valdevit A, Chang HG, Kanzaki K. Biomechanical testing of the lumbosacral spine. Spine (Phila Pa 1976) 1998;23:1721–8. 10. Abumi K, Saita M, Iida T, Kaneda K. Reduction and fixation of sacroiliac joint dislocation by the combined use of S1 pedicle screws and the galveston technique. Spine (Phila Pa 1976) 2000;25:1977–83. 11. Oh CW, Kim PT, Kim JW, Min WK, Kyuung HS, Kim SY, et al. Anterior plating and percutaneous iliosacral screwing in an unstable pelvic ring. J Orthop Sci 2008;13:107–15.
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12. Matta JM, Tornetta 3rd P. Internal fixation of unstable pelvic ring injuries. Clin Orthop Relat Res 1996;329:129–40. 13. Griffin DR, Starr AJ, Reinert CM, Jones AL, Whitlock S. Vertically unstable pelvic fractures fixed with percutaneous iliosacral screws: does posterior injury pattern predict fixation failure. J Orthop Trauma 2006;20(1 Suppl.):S30–6. 14. Pape HC, Giannoudis P, Krettek C. The timing of fracture treatment in polytrauma patients: relevance of damage control orthopedic surgery. Am J Surg 2002;183:622–9. 15. EI Assuity WI, EI Masry MA, Chan D. Acute traumatic spondylolisthesis at the lumbosacral junction. J Trauma 2007;62:1514–6. 16. Wright V, Zelle BA, Prayson M. Bilateral sacroiliac joint dislocation without associated fracture or anterior pelvic ring injuries. J Orthop Trauma 2004;18:634–7. 17. Beguiristain J, Schweitzer D, Mora G, Pombo V. Traumatic lumbosacral dislocation in a 5-year-old boy with eight years follow-up. Spine 1995;20:362–6. 18. Tile M. Acute pelvic fractures: I. Causation and classification. J Am Acad Orthop Surg 1996;4:143–51. 19. Giannoudis PV, Tzioupis CC, Pape HC, Roberts CS. Percutaneous fixation of the pelvic ring: an update. J Bone Joint Surg Br 2007;89:145–54. 20. Mouhsine E, Wettstein M, Schizas C, Borens O, Blanc CH, Leyvraz PF, et al. Modified triangular posterior osteosynthesis of unstable sacrum fracture. Eur Spine J 2006;15:857–63. 21. Schildhauer TA, Bellabarba C, Nork SE, Barei DP, Routt Jr ML, Chapman JR. Decompression and lumbopelvic fixation for sacral fracture-dislocations with spino-pelvic dissociation. J Orthop Trauma 2006;20:447–57. 22. Lim CT, Hee HT, Liu G. Traumatic spondylolisthesis of the lumbar spine: a report of three cases. J Orthop Surg 2009;17:361–5. 23. Bellabarba C, Schildhauer TA, Vaccaro AR, Chapman JR. Complications associated with surgical stabilization of high-grade sacral fracture dislocations with spino-pelvic instability. Spine (Phila Pa 1976) 2006;31:S80–8. 24. Tomlinson T, Chen J, Upasani V, Mahar A. Unilateral and bilateral sacropelvic fixation result in similar construct biomechanics. Spine (Phila Pa 1976) 2008;33:2127–33. 25. Carlson JR, Heller JG, Mansfield FL, Pedlow FX. Traumatic open anterior lumbosacral fracture dislocation – a report of two cases. Spine 1999;24:184–8. 26. Kaplan SS, Wright NM, Yundt KD, Lauryssen C. Adjacent fracture-dislocations of the lumbosacral spine: case report. Neurosurgery 1999;44:1134–7. 27. Kellam JF, McMurtry RY, Paley D, Tile M. The unstable pelvic fracture. Operative treatment. Orthop Clin North Am 1987;18:25–41. 28. Schildhauer T, Chapman JR, Mayo K. Multisegmental fracture of the sacrum due to impalement. J Orthop Trauma 2005;19:134–5. 29. Denis F, Davis S, Comfort T. Sacral fractures: an important problem. Retrospective analysis of 236 cases. Clin Orthop 1988;227:67–81. 30. Browner BD, Cole JD, Graham JM, Bondurant FJ, Nunchuck-Burns SK, Colter HB. Delayed posterior internal fixation of unstable pelvic fractures. J Trauma 1987;27:998–1006. 31. Zelle BA, Gruen GS, Hunt T, Speth SR. Sacral fractures with neurological injury: is early decompression beneficial? Int Orthop 2004;28:244–51. 32. Cohn SL, Keppler L, Arkarnia BA. Traumatic retrolisthesis of the lumbosacral junction. Spine 1989;14:132–4. 33. Robertson PA, Sherwood MJ, Hadlow AT. Lumbosacral dislocation injuries: management and outcomes. J Spinal Disord Technol 2005;June (18):232–7. 34. Hilibrand AS, Urquhart AG, Graziano GP, Hensinger RN. Acute spondylolytic spondylolisthesis. Risk of progression and neurological complications. J Bone Joint Surg Am 1995;77:190–6.
Contents lists available at SciVerse ScienceDirect
Injury journal homepage: www.elsevier.com/locate/injury
Management of lumbosacropelvic fracture-dislocation using lumbo-iliac internal fixation Hai-Chun Liu a, Yun-zhen Chen a, Xi-Guang Sang b,*, Lei Qi a a b
Department of Orthopedic and Trauma Surgery, Qilu Hospital, Shandong University, Jinan, Shandong 250012, China Department of Traumatic Emergency, Qilu Hospital, Shandong University, Jinan, Shandong 250012, China
A R T I C L E I N F O
A B S T R A C T
Article history: Accepted 25 August 2011
Objective: Traumatic lumbosacropelvic fracture-dislocation is a rare but potentially serious injury. Conventional methods like lumbosacral fixation used to treat such injuries often result in suboptimal outcome secondary to complications like pseudoarthroses, sagittal imbalance and hardware failure. In this study, we retrospectively analysed the clinical features and management for this trauma using lumbo-iliac fixation. Methods: Eight patients (6 male, 2 female; 21–52 years old, mean: 38.4) with traumatic lumbosacropelvic fracture-dislocation were surgically managed by lumbo-iliac internal fixation after lumbosacral decompression. Patients were followed up for 24–40 months (mean: 31.6). American Spine Injury Association (ASIA) scores were measured before surgery and at the last follow-up, and statistically analysed. Results: After surgery, all patients experienced improved sensory and motor performance. Six patients showed recovery of bowel and bladder functions. Immediately after lumbo-iliac fixation, all patients could turn in bed without assistance. Lumbosacral alignment was restored immediately after surgery and no dislocation was observed during follow-up. Radiography indicated excellent integration between the autograft and the vertebrae. After surgery, no patient experienced neurological deterioration. Conclusion: Our experience with these cases suggests that early surgical decompression and posterior lumbo-iliac internal fixation can effectively restore spinal alignment, stabilise the spine, and improve neurological symptoms for this complex trauma. ß 2011 Elsevier Ltd. All rights reserved.
Keywords: Lumbosacropelvic fracture Internal fixation Complex trauma
Introduction Traumatic lumbosacropelvic dislocation is a severe high-energy trauma that is usually combined with extensive soft tissue damage, haemorrhagic shock, and injuries to multiple organs.1 Therefore, it is associated with a high mortality. Currently there have been only a few case reports on lumbosacral dislocation, mainly pertaining to fracture-dislocation of the lumbosacral and sacroiliac joints, and sacral fracture combined with bilateral sacroiliac dislocation.2–6 Simultaneous damage to the pelvis and the lumbosacral and sacroiliac joints (termed here as traumatic lumbosacropelvic fracture-dislocation) is a rare but severe mode of trauma and its course, prognosis, and management has not been extensively investigated. The management of this condition is unique because of its difficult anatomical location, unique biomechanical forces acting in this region and poor sacral bone quality. A lumbosacro-
pelvic fracture-dislocation often affects the cauda equina and impairs lower extremity motor, bowel and bladder function. Some of the early case series suggested use of conservative (nonsurgical) treatment because of the difficulties associated with surgical procedures.7,8 The nonsurgical approach however did not provide optimal results. There were patients who did not improve neurologically and developed instability and deformities in the lumbosacral region, and some developed neurological deterioration.2,4,25,26 Open reduction and subsequent stabilisation is the standard of care, conservative procedures are reserved to very selected cases only.5,17,34 Therefore, these patients must be carefully observed and prepared for surgical treatment especially those with neurodeficit.32,33 Surgery is best done early as delay may result in fibrous malunion of the fractured bones, increasing the difficulty of surgical reduction and fixation, and the risk of iatrogenic injury to the cauda equina during manipulation.21,23,27– 31
* Corresponding author. Tel.: +86 13808939226; fax: +86 13808939226. E-mail addresses: [email protected] (H.-C. Liu), [email protected] (X.-G. Sang). 0020–1383/$ – see front matter ß 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.injury.2011.08.036
Surgical management of lumbosacropelvic dislocation-fracture requires an appropriate fixation technique. We report here management of lumbosacroiliac fracture-dislocation by a new lumbo-iliac fixation. In this study, we retrospectively analyse the
H.-C. Liu et al. / Injury, Int. J. Care Injured 43 (2012) 452–457
treatment of eight cases of lumbosacroiliac fracture-dislocation by this technique in our hospital.
453
procedures. In cases of dislocation combined with lumbar fractures, magnetic resonance imaging (MRI) was used to reveal the conditions of spinal cord compression.
Materials and methods Surgical operation Patients Eight patients (6 males, 2 females, 21–52 years old, mean: 38.4 years) with traumatic lumbosacroiliac fracture-dislocation were admitted to our hospital between May/2/2006 and November/1/ 2010 (Table 1). Three patients presented with L5–S1 dislocation combined with sacroiliac joint dislocation. The other five patients presented with sacral fracture-dislocation combined with sacroiliac joint dislocation. Moreover, in all patients the trauma was combined with anterior pelvic ring injury and other fractures. At the time of admission, seven patients were in a shock state and four patients had severe thoracoabdominal traumas. Four patients were given mechanical ventilation due to breathing difficulty. All patients had impaired lower limb mobility (extension-flexion dysfunction of the affected foot/ankle) and bowel and bladder function (difficult urination and defecation). The level of neurological injury in each patient was evaluated by the American Spinal Injury Association (ASIA) scoring system.14 Imaging All patients underwent emergency care immediately after admission. After recovering stable vital signs, they were examined by radiography and computed tomography (CT) to assess their injuries. All patients were found to have posterior pelvic ring damages, including one patient with three zone-I sacral fractures, three patients with zone-II fractures, and two patients with zoneIII fractures. Two patients had complete sacroiliac joint dislocations, and the other six patients had complete L5/S1 dislocationseparations. All patients had fractures of the superior articular process of S1, including three patients with free sacral fragments (including the superior articular process of S1), three patients with L5 isthmus fractures, one patient with a combined L1 fracture, and one patient with a combined L4 fracture. All patients were found to have anterior pelvic ring damages, including two patients with unilateral pubic ramus fractures, four patients with bilateral fractures of the pubic rami, two patients with pubic symphysis separations of >2.5 cm, and one patient with combined acetabular fracture-dislocation. Spiral CT and subsequent three-dimensional reconstruction were used to reveal the fracture at the articular process and vertebral isthmus, and free sacral fragments including the superior articular process of S1. The imaging information was used in the evaluation of trauma conditions and planning of surgical
Preoperative treatment Each patient was examined for general conditions and then was cared for in an ICU until resuscitation and target physiologic parameters were reached. After the patient’s condition became stable, the indication for surgical treatment was determined and the benefit of surgical treatment assessed. In these patients, the interval between trauma and definitive surgery ranged from 4 to 11 days (mean 7.2 days). Definitive surgery The patient was placed in a supine position and the anterior pelvic ring injury was treated, by open reduction and plate fixation. In cases of difficult reduction, an ilioinguinal incision was made and the dislocated sacroiliac joint was exposed, debrided and reduced. Then, the patient was switched to a prone position and underwent lumbo-iliac fixation, either by posterior midline incision or short posterior midline incision combined with bilateral arc incision to the posterior superior iliac spines (Fig. 1). The second approach was later found to be superior in several respects. It could directly expose the posterior superior iliac spine and the sacroiliac joint, avoid overstretch of the skin, suspend the sacral skin, reduce stimulation to the skin in cases of combined severe sacral fracture and sacral skin damage, theoretically increase the opportunity of fracture union and reduce occurrence of infection. The lumbar and sacral vertebrae were exposed and both were partially resected to allow decompression of the vertebral canal. Bone mass protruding into the canal was reduced or resected, and any dural sac rupture was repaired to prevent post-operative cerebrospinal fluid leakage and infection. Pedicle screws were inserted into L4 and L5. If S1 was intact, a pedicle screw was inserted into S1 in some cases. Rods were attached and distracted to reduce the dislocated vertebrae. The pedicle screw at S1 was omitted if it was too severely fractured to accept a pedicle screw. The superior articular process of S1 was resected if it was found to prevent the reduction. Before inserting the sacral screw, the posterior superior iliac spine (PSIS) was exposed and then a 1 cm 4 cm bone chip was removed from the inferior part of the PSIS to create a smooth bony bed. Perpendicular to this bony bed, a sacral screw was inserted into the posterior column of the ilium. A titanium link rod was bent into a desirable profile, attached to the screws, and fastened. The vertical dislocation of the ilium was reduced by distraction of the rod attached to the lumbar spine. The
Table 1 A summary of patient conditions, operations, and outcomes. Patient no.
Sex
Age (years)
1 2 3 4
Male Male Female Male
28 31 21 51
5 6 7
Female Male Male
47 38 52
8
Male
39
Cause of trauma
Motorcycle accident Impact Fall from height Impact due to traffic accident Fall from height Fall from height Crush under tricycle wheels Impact due to traffic accident
ISS score on admission
Trauma– surgery interval (days)
Surgery duration (h)
Bleeding volume (mL)
ASIA score before surgery
ASIA score at latest follow-up
Sensory
Motor
Sensory
Motor
Follow-up time (months)
24 29 21 34
8 10 7 15
4.3 4.5 3.7 4.5
1200 1450 1350 1700
40 32 38 33
38 28 36 27
68 45 68 44
46 36 43 36
32 27 24 33
45 24 35
21 5 14
4 3.5 5.5
1250 800 2800
30 46 32
22 40 28
37 66 38
27 48 35
25 40 33
33
10
5.3
2300
35
36
58
42
39
454
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Results
Fig. 1. A photograph showing incisions planned for internal lumbosacroiliac fixation.
horizontal dislocation of the ilium was reduced by compression of the horizontal connecting rod. The bone mass removed from the ilium was implanted into the intervertebral space for fusion. For patients with sacral fracture displacement, we debride the soft tissue between fracture fragments and decompress sacral neuroforamen, and then place tiny bone particles into the broken ends of fractured bone and perform compression to receive fracture healing. For patients with sacroiliac joint dislocation, we debride the residual ligament rupture, place tiny bone particles into dislocated joint and perform compression for sacroiliac joint fusion (Figs. 2 and 3). The whole procedure takes 3.5–5.5 h (mean 4.4 h) and the intraoperative bleeding volume ranged from 800 to 2800 mL (mean 1606 mL). The patient was instructed to stay in bed for 3–5 weeks and to participate in lower limb/joint functional exercise during the bed stay. Then, the patient was allowed to resume off-bed activities whilst wearing a waist brace. The patient underwent regular rehabilitation (hyperbaric oxygen treatment, and electric stimulation treatment) and neurotrophic drug treatment to accelerate the recovery of neurologic functions. Follow-up Patients were followed-up for 24–40 months (mean 31.6 months). They were evaluated using radiography for the status of fracture healing, spinal alignment, and stability at five time points: at 6 weeks, and 3, 6, 12, and 24 months after surgery. Radiographs were taken at dynamic postures when necessary to check for screw lessening or fracture. Before surgery and at the last follow-up, the sensory and motor performances of each patient were evaluated according to the ASIA scoring scale; rectal and bladder functions were also examined. Statistical analyses ASIA scores were analysed by paired t-tests with SPSS 11.5 (SPSS, Chicago, IL, USA), and a P-value less than 0.05 was considered statistically significant.
There was no mortality as a result of the procedure. After surgery, both the sensory and motor scores (Table 2) increased significantly, but still remained below the scores in normal individuals. In general, a patient with more severe trauma was also observed to have less recovery. After surgery, six patients showed different degrees of recovery of bowel and bladder function with good control of urination and defecation. The other two patients continued to experience severe bowel and bladder dysfunction and lacked the ability to control urination and defecation. Immediately after lumbo-iliac fixation, all patients could turn in bed without assistance. Patients who recovered neurological functions relatively early were able to resume off-bed activities from 3 weeks after surgery. Pain resulting from nerve root compression reduced immediately after surgery. Lumbosacral alignment was restored immediately after surgery and no dislocation was observed during follow-up. Radiography indicated excellent integration between the autograft and the vertebrae. After surgery, no patient experienced neurological deterioration. One patient who underwent posterior midline incision experienced delayed incision healing, but the incision eventually healed after debridement and suturing. One patient showed cerebrospinal fluid leakage and was cured by pressure dressing. One patient developed infection, probably related to the open sacral fracture-dislocation, which was controlled by debridement and antimicrobial treatment. Six patients experienced muscle disuse atrophy and stiffness, and were successfully managed by exercise and physical therapy. One patient experienced skin damage due to contact pressure from the end of an iliac screw. The skin rupture subsequently healed.
Discussion The lumbosacral area has a unique anatomy and is subject to unusual stresses. For effective weight transmission it is essential that the stability and anatomy of the region be restored after fracture dislocation. From these cases, we found that lumbo-iliac fixation combined with vertebral canal decompression and fusion is an effective treatment for traumatic lumbosacroplevic fracturedislocation. In these patients, the operation significantly improved sensory and motor capability of the lower limbs and bowel and bladder function. There have been a number of case reports on lumbosacral and sacroiliac fracture-dislocation.2,15,16 Lumbosacral dislocation combined with sacroiliac fracture was observed in a few cases, and named inconsistently.1,3 Here, we propose a general concept of traumatic lumbosacropelvic dislocation, characterised by damage to the lumbosacropelvic region combined with simultaneous injuries to L5, the sacrum, sacroiliac joint, ilium, and the anterior pelvic ring. This trauma affects both the anteroposterior and lateral stability of the lumbosacropelvic structure. It substantially changes the biomechanical structure of the lumbar vertebrae, the sacrum and pelvis and results in a high degree of instability. In this complex trauma setting, the high instability presents a challenge to surgical correction. Simple sacroiliac dislocation (e.g., without lumbosacral damage) can be fixed by several techniques.9–11 such as the use of anterior sacroiliac plates, posterior sacral rods, or sacroiliac screws. Matta et al.12 found that the sacral rod can produce inferior fixation compared with anterior sacroiliac plates. However, percutaneous insertion of sacroiliac screws involves substantial higher risks if sacral abnormalities are present.1,10 Additionally, in cases of sacral fracture with vertical displacement, the sacroiliac screw is prone to loosening and may result in loss of reduction.13
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Fig. 2. Images showing the lumbosacropelvic trauma in a 56-year-old male patient resulting from a vehicle accident; (a and b) 3D reconstructed images revealing complete dislocation of the left ilium combined with multiple transverse process fractures and left-posterior displacement of lumbar vertebra; (c and d) X-radiographs after surgery showing excellent spinal and iliac alignment and correct placement of iliac and sacroiliac screws.
Moushine et al.20 suggested that surgical management for unstable lumbosacral fracture should purport to reconstruct the lumbosacral joint, restore the spine-pelvis alignment, and reach early load bearing. Because of the difficult conditions in lumbosacropelvic fracture-dislocation, none of sacroiliac screws, sacral rods and anterior plates can provide sufficient stability.18,19 The lumbo-iliac fixation performed in these patients is a modified Galveston technique,10 and it was found to be effective for this complex trauma. For traumatic lumbosacropelvic dislocation, the lumbo-iliac fixation allows the body gravity to be transferred through the titanium rod, iliac screw, the posterior of the ilium, and then directly to the acetabulum, hence bypassing the fractured sacrum to allow an effective decompression of the sacral canal, so the patients could bear load 24 h after surgery. Reduction of the dislocated sacrum or sacroiliac joint is critical for the success of the operation. After preoperative skeletal traction, the ilium is vertically reduced by distracting the connector between the iliac screw and the lumbar rod, and
horizontally reduced by applying pressure on the connector to force the ilia to laterally separate. If the condition permits, a sacroiliac screw may be used to improve the stability and facilitate the recovery of the biomechanical function of the lumbosacroiliac region. Matta12 suggested that in cases of combined damage of the posterior and anterior pelvic rings, fixation of the posterior ring is necessary; if a strong fixation of the posterior ring is available the anterior ring fixation may be omitted. Schildhauer21 believed that the anterior ring should be first fixed to provide stability and help the reduction of the posterior ring. Our experience with these patients also suggests that the anterior ring should be first fixed in case of large fracture-dislocation of the pubic rami or separation of the public symphysis. We performed anterior ring fixation in all patients to increase stability as well as reduce the stress associated with posterior fixation alone. Verlaan4 reported that damages to the lumbosacral plexus and the sacral nerve during traumatic lumbosacral dislocation are
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456
Fig. 3. Images showing the trauma in a 48-year-old female patient resulting from a vehicle accident; (a) an axial CT before surgery revealing bilateral separation of the sacroiliac joints and comminuted fracture of the right sacrum; (b) a radiograph before surgery showing fracture-dislocation of the anterior pelvic ring; (c) a radiograph after surgery showing correct placement of iliac screws, connecting rods, and fixation plates; (d) a radiograph after surgery showing accurate placement of iliac screws into posterior columns of the ilia.
usually traction injuries. Under this injury mode, decompression can result in only limited recovery of neurological function but might impair spinal stability. Therefore, they believed that the primary purpose of surgical management should be restoring spinal stability, followed by recovery of neurological function. Chin et al.,22 however, observed in three cases that early decompression improved the neurological function, and identified the decompression time and the degree of spinal stenosis as major influential factors in neurological recovery. Patients with lumbosacral dislocation, particularly those undergoing a delayed surgical treatment, may develop traction injuries during reduction due to scar adhesion around the lumbosacral nerves. Therefore it is critical to check the spinal canal for any protruding disc tissue or bony mass before reduction. Our experience suggests that if neurological symptoms and clear imaging evidence of spinal compression are present beforehand, the canal should be decompressed during surgery, the adhesion be released, and a structure protruding into the spinal canal should be resected Table 2 Comparison of ASIA scores before surgery and at the last follow-up (mean standard deviation).
Sensory score Motor score
Before surgery
Latest follow-up
t-Value
P-value
35.75 5.31 31.88 6.42
53.00 13.47 39.13 6.90
5.24 16.00
0.0012 <0.0001
before reduction to prevent any nerve traction and facilitate neurological recovery. Most patients in this report showed clear recovery of neurological function and excellent lumbar-pelvic stability, which favoured early off-bed activity. The patients treated by lumbar-iliac fixation experienced relatively few complications. In comparison, an earlier study reported sacral fracture to have an infection rate of 16% and the rate of delayed healing to be 14%.23 Our approach on the subsequent five patients (a short incision at the posterior midline combined with bilateral arc incisions at the posterior superior iliac spines) was found to effectively prevent incision infection and delay healing, probably because it reduced secondary damage to the already-damaged sacral skin and prevented excessive skin traction. Compression of the skin by fixation instruments deserves concern. An early patient developed skin necrosis resulting from compression by the protruding fixation instrument. In our operations with the later patients, the bone at the screwing location was typically removed by approximately 1 cm to sink the screw head slightly below the posterior superior iliac spine. Like most studies, ours also fails to address and resolve certain issues. The use of unilateral lumbo-iliac fixation versus bilateral fixation has been widely debated. Tomilson et al.24 in their biomechanical study demonstrated a superior outcome with unilateral fixation, as compared to bilateral lumbo iliac fixation. In our studies we did both unilateral and bilateral fixation depending on the severity of trauma and the nature of the
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expected instability, and we could not arrive at any conclusion regarding superiority of one over the other. We also used a different surgical approach in the later group and reached a conclusion vis-a`-vis superiority of the later approach that involved a small midline and tow accessory para-spinal incisions along the arch of iliac crest, but we did not give a statistical analysis and comparison between two surgical approach. Our studies also have obvious limitations, include generalisability (complex anatomy, high demanding technique, catastrophic complications), heterogeneous demographic characters and injuries of the enrolled cases, lack of a control group. Although the series reported here is small, we believe that it provides valuable information of a promising fixation technique for this complex trauma. In conclusion, our experience with these patients shows that preoperative planning and resuscitation following the principles of damage control surgery (DCS) are critical. Decompression of the spinal canal and internal lumbo-iliac fixation can effectively improve neurological function, stabilise fractures, restore spinal alignment, prevent deformity, favour early activities, and reduce complications. References 1. Vresilovic EJ, Mehta S, Placide R, Milam 4th RA. Traumatic spondylopelvic dissociation. A report of two cases. J Bone Joint Surg Am 2005;87:1098–103. 2. Cruz-Conde R, Rayo A, Rodriguez de Oya R, Berjano P, Ga´rate E. Acute traumatic lumbosacral dislocation treated by open reduction internal fixation and fusion. Spine (Phila Pa 1976) 2003;28:E51–3. 3. Bents RT, France JC, Glover JM, Kaylor KL. Traumatic spondylopelvic dissociation. A case report and literature review. Spine (Phila Pa 1976) 1996;21:1814–9. 4. Verlaan JJ, Oner FC, Dhert WJ, Verbout AJ. Traumatic lumbosacral dislocation: case report. Spine (Phila Pa 1976) 2001;26:1942–4. 5. Veras del Monte LM, Bago´ J. Traumatic lumbosacral dislocation. Spine (Phila Pa 1976) 2000;25(6):756–9. 6. Whitbeck Jr MG, Zwally 2nd HJ, Burgess AR. Innominosacral dissociation: mechanism of injury as a predictor of resuscitation requirements, morbidity, and mortality. J Orthop Trauma 1997;11:82–8. 7. Tile M. Pelvic ring fractures: should they be fixed? J Bone Joint Surg Br 1988;70:1–12. 8. Phelan ST, Jones DA, Bishay M. Conservative management of transverse fractures of the sacrum with neurological features: a report of four cases. J Bone Joint Surg Br 1991;73:969–71. 9. Kostuik JP, Valdevit A, Chang HG, Kanzaki K. Biomechanical testing of the lumbosacral spine. Spine (Phila Pa 1976) 1998;23:1721–8. 10. Abumi K, Saita M, Iida T, Kaneda K. Reduction and fixation of sacroiliac joint dislocation by the combined use of S1 pedicle screws and the galveston technique. Spine (Phila Pa 1976) 2000;25:1977–83. 11. Oh CW, Kim PT, Kim JW, Min WK, Kyuung HS, Kim SY, et al. Anterior plating and percutaneous iliosacral screwing in an unstable pelvic ring. J Orthop Sci 2008;13:107–15.
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