1
|
Bryson XM, Pham NS, Hollyer I, Hu S, Rinsky LA, Vorhies JS. 3D CT modeling demonstrates the anatomic feasibility of S1AI screw trajectory for spinopelvic fixation in neuromuscular scoliosis. Spine Deform 2024:10.1007/s43390-024-00840-z. [PMID: 38733488 DOI: 10.1007/s43390-024-00840-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 02/07/2024] [Indexed: 05/13/2024]
Abstract
PURPOSE In patients with neuromuscular scoliosis undergoing posterior spinal fusion, the S2 alar iliac (S2AI) screw trajectory is a safe and effective method of lumbopelvic fixation but can lead to implant prominence. Here we use 3D CT modeling to demonstrate the anatomic feasibility of the S1 alar iliac screw (S1AI) compared to the S2AI trajectory in patients with neuromuscular scoliosis. METHODS This retrospective study used CT scans of 14 patients with spinal deformity to create 3D spinal reconstructions and model the insertional anatomy, max length, screw diameter, and potential for implant prominence between 28 S2AI and 28 S1AI screw trajectories. RESULTS Patients had a mean age of 14.42 (range 8-21), coronal cobb angle of 85° (range 54-141), and pelvic obliquity of 28° (range 4-51). The maximum length and diameter of both screw trajectories were similar. S1AI screws were, on average, 6.3 ± 5 mm less prominent than S2AI screws relative to the iliac crests. S2AI screws were feasible in all patients, while in two patients, posterior elements of the lumbar spine would interfere with S1AI screw insertion. CONCLUSION In this cohort of patients with neuromuscular scoliosis, we demonstrate that the S1AI trajectory offers comparable screw length and diameter to an S2AI screw with less implant prominence. An S1AI screw, however, may not be feasible in some patients due to interference from the posterior elements of the lumbar spine.
Collapse
Affiliation(s)
- Xochitl M Bryson
- Department of Orthopaedic Surgery, Stanford University School of Medicine, 453 Quarry Rd, 3rd Floor, MC 5658, Palo Alto, CA, USA
| | - Nicole S Pham
- Department of Orthopaedic Surgery, Stanford University School of Medicine, 453 Quarry Rd, 3rd Floor, MC 5658, Palo Alto, CA, USA
| | - Ian Hollyer
- Department of Orthopaedic Surgery, Stanford University School of Medicine, 453 Quarry Rd, 3rd Floor, MC 5658, Palo Alto, CA, USA
| | - Serena Hu
- Department of Orthopaedic Surgery, Stanford University School of Medicine, 453 Quarry Rd, 3rd Floor, MC 5658, Palo Alto, CA, USA
| | - Lawrence A Rinsky
- Department of Orthopaedic Surgery, Stanford University School of Medicine, 453 Quarry Rd, 3rd Floor, MC 5658, Palo Alto, CA, USA
| | - John S Vorhies
- Department of Orthopaedic Surgery, Stanford University School of Medicine, 453 Quarry Rd, 3rd Floor, MC 5658, Palo Alto, CA, USA.
| |
Collapse
|
2
|
Kaul R, Goswami B, Kumar K, Jeyaraman M, Sangondimath G, Chhabra HS. A Computed Tomography-Based Assessment of the Anatomical Parameters Concerning S2-Alar Iliac Screw Insertion Using "Safe Trajectory Method" in Indian Population. Asian Spine J 2023; 17:130-137. [PMID: 35527531 PMCID: PMC9977994 DOI: 10.31616/asj.2022.0034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 02/20/2022] [Indexed: 11/23/2022] Open
Abstract
STUDY DESIGN A retrospective computed tomography (CT)-based radiological analysis. PURPOSE To obtain CT-based morphometric data for the S2 alar iliac (S2AI) screw in the Indian population presenting to School of Medical Sciences and Research, Greater Noida, we used the concept of "safe trajectory" by Pontes and his colleagues in a recent study. OVERVIEW OF LITERATURE Although previous CT-based morphometric studies on the S2AI screw have been published for a variety of ethnic groups, morphometric data specifically for the Indian population are scarce. METHODS We used the three-dimensional multiplanar reformatting software to conduct a retrospective CT analysis of 112 consecutive patients who met our exclusion criteria for various abdominal and pelvic pathologies. CT imaging planes were rotated between the S1 and S2 foramen until they matched the ideal S2AI screw trajectory, which was represented by the longest and widest iliac osseous channel observed in the axial CT section. Following the concept of a safe trajectory, S2AI screw morphometric parameters were measured on both sides of the pelvis using corresponding axial and sagittal CT images. RESULTS In the sagittal and transverse planes on both sides of the pelvis, females had significantly higher screw trajectory angulation than males (p<0.001). On both sides of the pelvis, males had significantly greater iliac width, maximum screw trajectory length, and intrascrotal length than females (p<0.001). On both sides of the pelvis, the S2AI screw entry point in females was significantly deeper than in males from the skin margin (p<0.001). CONCLUSIONS Based on our methodology, we discovered that the S2AI screw trajectory is significantly more caudal and lateral in females, the maximum screw length is sufficient for use in clinical practice regardless of gender, and that 8.5 mm or even larger screw diameters are feasible in the majority of the Indian population.
Collapse
Affiliation(s)
- Rahul Kaul
- Department of Orthopaedics, School of Medical Sciences and Research, Sharda University, Greater Noida,
India
| | - Bharat Goswami
- Department of Orthopaedics, School of Medical Sciences and Research, Sharda University, Greater Noida,
India
| | - Khemendra Kumar
- Department of Radio Diagnosis, School of Medical Sciences and Research, Sharda University, Greater Noida,
India
| | - Madhan Jeyaraman
- Department of Orthopaedics, School of Medical Sciences and Research, Sharda University, Greater Noida,
India
| | | | - HS Chhabra
- Department of Spine Services, Indian Spinal Injuries Centre, New Delhi,
India
| |
Collapse
|
3
|
Martin CT, Holton KJ, Elder BD, Fogelson JL, Mikula AL, Kleck CJ, Calabrese D, Burger EL, Ou-Yang D, Patel VV, Kim HJ, Lovecchio F, Hu SS, Wood KB, Harper R, Yoon ST, Ananthakrishnan D, Michael KW, Schell AJ, Lieberman IH, Kisinde S, DeWald CJ, Nolte MT, Colman MW, Phillips FM, Gelb DE, Bruckner J, Ross LB, Johnson JP, Kim TT, Anand N, Cheng JS, Plummer Z, Park P, Oppenlander ME, Sembrano JN, Jones KE, Polly DW. Catastrophic acute failure of pelvic fixation in adult spinal deformity requiring revision surgery: a multicenter review of incidence, failure mechanisms, and risk factors. J Neurosurg Spine 2023; 38:98-106. [PMID: 36057123 DOI: 10.3171/2022.6.spine211559] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 06/17/2022] [Indexed: 01/04/2023]
Abstract
OBJECTIVE There are few prior reports of acute pelvic instrumentation failure in spinal deformity surgery. The objective of this study was to determine if a previously identified mechanism and rate of pelvic fixation failure were present across multiple institutions, and to determine risk factors for these types of failures. METHODS Thirteen academic medical centers performed a retrospective review of 18 months of consecutive adult spinal fusions extending 3 or more levels, which included new pelvic screws at the time of surgery. Acute pelvic fixation failure was defined as occurring within 6 months of the index surgery and requiring surgical revision. RESULTS Failure occurred in 37 (5%) of 779 cases and consisted of either slippage of the rods or displacement of the set screws from the screw tulip head (17 cases), screw shaft fracture (9 cases), screw loosening (9 cases), and/or resultant kyphotic fracture of the sacrum (6 cases). Revision strategies involved new pelvic fixation and/or multiple rod constructs. Six patients (16%) who underwent revision with fewer than 4 rods to the pelvis sustained a second acute failure, but no secondary failures occurred when at least 4 rods were used. In the univariate analysis, the magnitude of surgical correction was higher in the failure cohort (higher preoperative T1-pelvic angle [T1PA], presence of a 3-column osteotomy; p < 0.05). Uncorrected postoperative deformity increased failure risk (pelvic incidence-lumbar lordosis mismatch > 10°, higher postoperative T1PA; p < 0.05). Use of pelvic screws less than 8.5 mm in diameter also increased the likelihood of failure (p < 0.05). In the multivariate analysis, a larger preoperative global deformity as measured by T1PA was associated with failure, male patients were more likely to experience failure than female patients, and there was a strong association with implant manufacturer (p < 0.05). Anterior column support with an L5-S1 interbody fusion was protective against failure (p < 0.05). CONCLUSIONS Acute catastrophic failures involved large-magnitude surgical corrections and likely resulted from high mechanical strain on the pelvic instrumentation. Patients with large corrections may benefit from anterior structural support placed at the most caudal motion segment and multiple rods connecting to more than 2 pelvic fixation points. If failure occurs, salvage with a minimum of 4 rods and 4 pelvic fixation points can be successful.
Collapse
Affiliation(s)
| | - Kenneth J Holton
- 1Department of Orthopaedic Surgery, University of Minnesota, Minneapolis
| | - Benjamin D Elder
- 2Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota
| | - Jeremy L Fogelson
- 2Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota
| | - Anthony L Mikula
- 2Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota
| | - Christopher J Kleck
- 3Department of Orthopedics, University of Colorado, School of Medicine, Aurora, Colorado
| | - David Calabrese
- 3Department of Orthopedics, University of Colorado, School of Medicine, Aurora, Colorado
| | - Evalina L Burger
- 3Department of Orthopedics, University of Colorado, School of Medicine, Aurora, Colorado
| | - David Ou-Yang
- 3Department of Orthopedics, University of Colorado, School of Medicine, Aurora, Colorado
| | - Vikas V Patel
- 3Department of Orthopedics, University of Colorado, School of Medicine, Aurora, Colorado
| | - Han Jo Kim
- 4Department of Orthopaedic Surgery, Hospital for Special Surgery, New York, New York
| | - Francis Lovecchio
- 4Department of Orthopaedic Surgery, Hospital for Special Surgery, New York, New York
| | - Serena S Hu
- 5Department of Orthopaedic Surgery, Stanford University, Stanford, California
| | - Kirkham B Wood
- 5Department of Orthopaedic Surgery, Stanford University, Stanford, California
| | - Robert Harper
- 5Department of Orthopaedic Surgery, Stanford University, Stanford, California
| | - S Tim Yoon
- 6Department of Orthopaedics, Emory University, Atlanta, Georgia
| | | | - Keith W Michael
- 6Department of Orthopaedics, Emory University, Atlanta, Georgia
| | - Adam J Schell
- 6Department of Orthopaedics, Emory University, Atlanta, Georgia
| | | | - Stanley Kisinde
- 7Scoliosis and Spine Tumor Center, Texas Back Institute, Plano, Texas
| | - Christopher J DeWald
- 8Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, Illinois
| | - Michael T Nolte
- 8Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, Illinois
| | - Matthew W Colman
- 8Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, Illinois
| | - Frank M Phillips
- 8Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, Illinois
| | - Daniel E Gelb
- 9Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Jacob Bruckner
- 9Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Lindsey B Ross
- 10Department of Neurologic Surgery, Cedars-Sinai Medical Center, Los Angeles
| | - J Patrick Johnson
- 10Department of Neurologic Surgery, Cedars-Sinai Medical Center, Los Angeles
| | - Terrence T Kim
- 11Department of Orthopaedics, Cedars-Sinai Medical Center, Los Angeles, California
| | - Neel Anand
- 11Department of Orthopaedics, Cedars-Sinai Medical Center, Los Angeles, California
| | - Joseph S Cheng
- 12Department of Neurosurgery, University of Cincinnati College of Medicine, Cincinnati, Ohio; and
| | - Zach Plummer
- 12Department of Neurosurgery, University of Cincinnati College of Medicine, Cincinnati, Ohio; and
| | - Paul Park
- 13Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan
| | - Mark E Oppenlander
- 13Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan
| | | | - Kristen E Jones
- 1Department of Orthopaedic Surgery, University of Minnesota, Minneapolis
| | - David W Polly
- 1Department of Orthopaedic Surgery, University of Minnesota, Minneapolis
| |
Collapse
|
4
|
Mun F, Vankara A, Suresh KV, Margalit A, Sponseller PD. Sacral-Alar-Iliac (SAI) Fixation in Patients With Previous Pelvic Osteotomy. Clin Spine Surg 2022; 35:E702-E705. [PMID: 35501910 DOI: 10.1097/bsd.0000000000001339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 04/09/2022] [Indexed: 01/25/2023]
Abstract
STUDY DESIGN This was a retrospective study. OBJECTIVE The purpose of this study was to investigate the technical challenges and outcomes of sacral-alar-iliac (SAI) fixation for scoliosis in patients who had previously undergone a pelvic osteotomy for hip dysplasia. SUMMARY OF BACKGROUND DATA Patients with neuromuscular disease are at high risk for developing hip dislocation and scoliosis. Surgical correction of one may affect the other. METHODS We reviewed the records of patients aged 18 years and below who underwent spinal fusion using SAI screws after having undergone a pelvic osteotomy, with ≥2-year follow-up. We recorded the SAI screw dimensions, time from osteotomy to SAI fixation, type of osteotomy, and any complications performing SAI fixation due to the pelvic osteotomy. Bivariate statistics were used to analyze the data with statistical significance defined as P -value <0.05. RESULTS Thirty-two patients were included. The average age was 10.3±3.2 years at pelvic osteotomy and 13.5±3.4 years at SAI fixation. Most patients had cerebral palsy (87.5%) and a unilateral Dega osteotomy (78.1%). Average screw dimensions were significantly shorter on the side of the osteotomy (66 vs. 72 mm, P <0.05). SAI screw placement was technically challenging in 8 patients (25%), due to pelvic distortion from the pelvic osteotomy. The use of a curved awl helped to find the intracortical channel. No patients had complications due to the SAI screw, and there were no significant differences in pelvic obliquity and major coronal curve correction. Two patients (6.3%) had screw lucency >2 mm around the SAI screw on the side of the pelvic osteotomy but no clinical symptoms. CONCLUSIONS SAI fixation in patients with previous pelvic osteotomy is technically challenging due to pelvic morphology and prior implants. Often, a shorter SAI screw is required on the side of the osteotomy. However, outcomes in this patient population are satisfactory, with no significant complications at a 2-year follow-up. LEVEL OF EVIDENCE Level IV.
Collapse
Affiliation(s)
- Frederick Mun
- Department of Orthopaedic Surgery, Johns Hopkins University, Baltimore, MD
| | | | | | | | | |
Collapse
|
5
|
Kassab Hassan S, Simon L, Campana M, Julien-Marsollier F, Simon AL, Ilharreborde B. S2-Alar-iliac screw fixation for paediatric neuromuscular scoliosis: Preliminary results after two years. Orthop Traumatol Surg Res 2022; 108:103234. [PMID: 35144011 DOI: 10.1016/j.otsr.2022.103234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 04/27/2021] [Accepted: 04/30/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND Correcting pelvic obliquity is among the main goals of surgery for neuromuscular scoliosis. Spino-pelvic fixation must be stable and capable of withstanding the considerable mechanical forces applied at the lumbo-sacral junction. Selection of the best anchoring option is therefore crucial. S2-alar-iliac (S2AI) screws, which are used in adults, are less often chosen in the French paediatric spinal-surgery community. The objective of this study was to report our preliminary experience with S2AI screws used in the treatment of paediatric patients with neuromuscular scoliosis. HYPOTHESIS Pelvic anchoring by means of S2AI screws is reliable and technically feasible in non-ambulatory children with neuromuscular scoliosis. MATERIALS AND METHODS Consecutive non-ambulatory patients who underwent scoliosis surgery with S2AI screw fixation to the pelvis between 2016 and 2018 were retrospectively included. The surgical procedure consisted in either posterior spinal fusion (PSF) or magnetic growing rod (MGR) implantation. In all patients, radiographs were obtained before surgery, within 3 months after surgery, and at last follow-up; and low-dose computed tomography (CT) was performed before and after surgery. RESULTS We included 25 patients with a mean age of 13.8±4.0 years, 18 managed by PSF and 7 by MGRs. Screw diameters ranged from 7.5 to 9.5mm and all screws were at least 60mm in length. The diameters and lengths were the same on both sides in 16 (89%) patients in the PSF group and in all patients in the MGR group. At last follow-up after a mean of 35.5±3.0 months, pelvic obliquity was corrected in all 23 patients with this abnormality before surgery. Complications consisted of lateral cortical screw breakthrough in 8 (32% of screws) patients and screw malposition in 2 (8% of screws) patients. No clinically significant complications related to the fixation material were recorded. DISCUSSION The results of our study demonstrate the feasibility of S2AI screw fixation in paediatric patients with neuromuscular scoliosis. Pelvic asymmetry and dysmorphism do not contra-indicate the procedure but must be evaluated before surgery. Further work is needed to assess the potential long-term consequences on pain and growth of screw passage through the sacro-iliac joints. LEVEL OF EVIDENCE IV, retrospective study.
Collapse
Affiliation(s)
- Sammy Kassab Hassan
- Service de chirurgie infantile à orientation orthopédique, Hôpital Universitaire Robert Debré, Assistance Publique - Hôpitaux de Paris (AP-HP), Université de Paris, 48 Bd Sérurier, 75019 Paris, France
| | - Laurie Simon
- Service de chirurgie infantile à orientation orthopédique, Hôpital Universitaire Robert Debré, Assistance Publique - Hôpitaux de Paris (AP-HP), Université de Paris, 48 Bd Sérurier, 75019 Paris, France
| | - Matthieu Campana
- Service de chirurgie infantile à orientation orthopédique, Hôpital Universitaire Robert Debré, Assistance Publique - Hôpitaux de Paris (AP-HP), Université de Paris, 48 Bd Sérurier, 75019 Paris, France
| | - Florence Julien-Marsollier
- Service d'anesthésie - réanimation pédiatrique, Hôpital Universitaire Robert Debré, Assistance Publique - Hôpitaux de Paris (AP-HP), Université de Paris, 48 Bd Sérurier, 75019 Paris, France
| | - Anne-Laure Simon
- Service de chirurgie infantile à orientation orthopédique, Hôpital Universitaire Robert Debré, Assistance Publique - Hôpitaux de Paris (AP-HP), Université de Paris, 48 Bd Sérurier, 75019 Paris, France.
| | - Brice Ilharreborde
- Service de chirurgie infantile à orientation orthopédique, Hôpital Universitaire Robert Debré, Assistance Publique - Hôpitaux de Paris (AP-HP), Université de Paris, 48 Bd Sérurier, 75019 Paris, France
| |
Collapse
|
6
|
Mun F, Vankara A, Suresh KV, Margalit A, Crasta N, Sponseller PD. Pelvic Osteotomy in Patients With Previous Sacral-Alar-Iliac (SAI) Fixation. J Pediatr Orthop 2022; 42:376-381. [PMID: 35522850 DOI: 10.1097/bpo.0000000000002166] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Patients with neuromuscular disease are at high risk for developing hip dysplasia and scoliosis. The purpose of this study was to investigate the technical challenges and outcomes of pelvic osteotomy in patients with prior sacral-alar-iliac (SAI) fixation. METHODS We reviewed clinical and radiographic records of patients aged 18 years and below who underwent pelvic osteotomy after SAI fixation. We recorded technical challenges during the osteotomy, time from SAI fixation to osteotomy, type of osteotomy, migration index, and distance from the SAI screw to the acetabulum. A 2-sample Wilcoxon rank-sum test was used to assess the data. RESULTS Nineteen patients were included. Technical challenges were defined as having greater intraoperative fluoroscopy times and noted difficult osteotomy in the operative report. The mean time from SAI fixation to pelvic osteotomy was 2.2±1.5 years. For all 12 Chiari osteotomies, the ilium could not be laterally displaced; however, medial displacement of the distal segment of the osteotomy allowed adequate coverage. All 7 Dega osteotomies were performed by cutting the cortex at the tip of the SAI screw. The screw improved proximal leverage and provided a strong buttress for bone graft. The mean migration index before pelvic osteotomy was 59±19%, and at most recent follow-up was 13±4%. Twelve patients, who had a noted complicated osteotomy, had SAI screws that were ≤1.87 cm ( P <0.01) from the acetabulum and significantly increased intraoperative fluoroscopy time (1.76 vs. 1.18 min, P <0.01). CONCLUSIONS The presence of SAI screws may cause iliac osteotomies to be technically challenging if the tip of the SAI screw is ≤1.87 cm to the acetabulum. When initially implanting SAI screws in neuromuscular patients, surgeons should attempt to place screw tips ∼2 cm from the acetabulum in the event these patients require subsequent pelvic osteotomy. LEVEL OF EVIDENCE Level IV.
Collapse
Affiliation(s)
- Frederick Mun
- Department of Orthopaedic Surgery, Johns Hopkins University, Baltimore, MD
| | | | | | | | | | | |
Collapse
|
7
|
Ulusaloglu AC, Asma A, Bowen JR, Yorgova P, Howard JJ, Shrader MW, Shah SA. Prevalence and Risk Factors Associated With Pelvic Rod/Screw Radiographic Lucency Following Scoliosis Surgery in Spastic Cerebral Palsy: A Longitudinal Study. J Pediatr Orthop 2022; 42:e736-e741. [PMID: 35650685 DOI: 10.1097/bpo.0000000000002173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Radiographic lucency around a smooth pelvic rod (Galveston/unit rod technique) or sacroiliac/iliac screw following spinal fusion in children with nonambulatory spastic cerebral palsy (CP) has been described as a "windshield wiper" phenomenon. We evaluated demographics, radiographs, and complications in 101 cases from a single center to determine prevalence, risk factors, and complications associated with persistent radiographic lucency from 1 to 5 years following spinal fusion. METHODS Inclusion criteria were diagnosis of nonambulatory spastic quadriplegic CP [Gross Motor Function Classification System (GMFCS) IV-V], under 18 years of age, scoliosis treated by posterior fusion from upper thoracic to sacrum with pelvic fixation (Galveston rod, iliac screw, or sacroiliac screw), adequate radiographs (preoperative, immediate postoperative, first-year, and second-year), and minimum 5-year follow-up. We evaluated demographics, radiographic parameters, comorbidities, scoliosis curve type, type of pelvic screw/rod, use of off-set connector, screw width, associated with posterior column osteotomy and/or additional anterior spinal release concurrent with posterior spine fusion, and infection over the follow-up period. Specific attention was given to the area and shape of the radiographic lucency. The logistic regression analysis was performed for continuous and categorical variables to define risk factors ( P =0.05). RESULTS In 101 patients, data were collected at mean intervals of 1-year, 2-year, and >5-year follow-up and were 12.9±1.5, 25.8±2.5, and 81.5±23.0 months, respectively. Prevalence of pelvic rod/screw radiographic lucency was unchanged at 33%, 35%, and 24% at 1-year, 2-year, and >5-year follow-up, respectively, and radiographic parameters did not change ( P >0.05). Furthermore, no risk factors or complications were associated with radiographic lucency around pelvic rods/screws ( P >0.05). CONCLUSION In patients with spastic nonambulatory CP who had scoliosis treated with posterior spinal fusion from upper thorax to pelvis, the prevalence of pelvic rod/screw lucency is high. Persistent lucency >2 mm around pelvic implants is not clinically significant, does not warrant advanced imaging, or indicate a complication if stable over time and wider distally than proximally. LEVEL OF EVIDENCE Level III.
Collapse
|
8
|
Mun F, Vankara A, Suresh KV, Margalit A, Kebaish KM, Sponseller PD. Sacral-Alar-Iliac (SAI) Fixation in Children With Spine Deformity: Minimum 10-Year Follow-Up. J Pediatr Orthop 2022; 42:e709-e712. [PMID: 35575763 DOI: 10.1097/bpo.0000000000002187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Sacral-alar-iliac (SAI) screws are utilized to achieve pelvic fixation in spine deformity patients. The primary purpose of this study is to investigate the long-term outcomes of pediatric patients with scoliosis treated with posterior spinal fusion and SAI fixation at 10-year clinical and radiographic follow-up. METHODS We reviewed the clinical and radiographic records of patients aged 18 years or below treated for scoliosis with posterior spinal fusion using SAI fixation. Pelvic obliquity and the major coronal curve were determined at the preoperative visit and 6-week, 1-year, 5-year, and 10-year postoperative visits. SAI screw-specific data collected included screw dimensions, rate of screw revision, pain at the SAI screw sites, presence of lucency >2 mm around the screw, screw loosening or breaking, and deep surgical site infections. RESULTS Ninety-seven of 151 patients (75%) were included. The average age at index surgery was 13.5±3.1 years, and the most common diagnosis was cerebral palsy (67%). The mean duration of follow-up was 11±3 years. The mean pelvic obliquity measured 20±8.0 degrees preoperatively, and 8.7±4.0 degrees at the 10-year follow-up. There were no significant difference in pelvic obliquity when comparing the 10-year follow-up visit with the 6-week postoperative follow-up. Average screw dimensions were 8.4×68.8 mm. By the 10-year follow-up, 4 patients (4%) had at least 1 SAI screw-related complication. Of these patients, 2 (2%) had pain at 1 SAI screw, 4 (4%) had lucency around the screw, and 3 (3%) had broken or loose screws. Two (2%) required SAI screw revision because of late deep wound infection, and underwent exchange with a longer screw. There were no intrapelvic protrusions, vascular, or neurological complications. CONCLUSIONS SAI screws are a safe and effective method for pelvic fixation in children with spinal deformity. The outcomes at ≥10 years are satisfactory, with low rates of long-term complications and excellent postoperative correction and subsequent maintenance of coronal curvature and pelvic obliquity over time. LEVEL OF EVIDENCE Level IV.
Collapse
Affiliation(s)
- Frederick Mun
- Department of Orthopaedic Surgery, Johns Hopkins University, Baltimore, MD
| | | | | | | | | | | |
Collapse
|
9
|
Rates of Loosening, Failure, and Revision of Iliac Fixation in Adult Deformity Surgery. Spine (Phila Pa 1976) 2022; 47:986-994. [PMID: 35819333 DOI: 10.1097/brs.0000000000004356] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 03/05/2022] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Retrospective cohort review of a prospective multicenter database. OBJECTIVE Identify rates and variations in lumbopelvic fixation failure after adult spinal deformity (ASD) correction. SUMMARY OF BACKGROUND DATA Traditional iliac (IS) and S2-alar-iliac (S2AI) pelvic fixation methods have unique technical characteristics for their application, and result in varied bio-mechanical and anatomic impact. These differences may lead to variance in lumbopelvic fixation failure types/rates. METHODS ASD patients undergoing correction with more than five level fusion and pelvic fixation, separated by pelvic fixation type (IS vs. S2AI). Fixation fracture or loosening assessed radiographically (Figure 1). Multivariate logistic regression, accounting for significant confounders, was used to examine differences between the two groups for screw loosening/fracture, rod fracture, and revision surgery. Level of significance set at P< 0.05. RESULTS Four hundred eighteen of 1422 patients were included (IS = 287, S2AI = 131). The groups had similar age, body mass index (BMI), baseline comorbidities, number of levels fused (P>0.05), baseline health related quality of life measures (HRQLs) (short form survey-36, Oswestry Disability Index [ODI], Scoliosis Research Society [SRS-22], numeric rating scale [NRS] leg and back, P>0.05) and deformity (pelvic tilt [PT], pelvic incidence-lumbar lordosis [PI-LL], and sagittal vertical axis [SVA], P> 0.05). The IS group had more unilateral fixation versus S2AI (12.9% vs. 6%; P = 0.02). The overall lumbopelvic fixation failure rate was 23.74%. Pelvic fixation (13.4%) and S1 screw (2.9%) loosening was more likely with S2AI (odds ratio [OR] 2.63, P = 0.001; OR 6.05, P = 0.022). Pelvic screw (2.3%) and rod fracture (14.1%) rates similar between groups but trended toward less occurrence with S2AI (OR 0.47, P= 0.06). Revision surgery occurred in 22.7%, and in 8.5% for iliac fixation specifically, but with no differences between fixation types (P = 0.55 and P = 0.365). Pelvic fixation failure conferred worse HRQL scores (physical component score [PCS] 36.23 vs. 39.37, P= 0.04; ODI 33.81 vs. 27.93, P = 0.036), and less 2 years improvement (PCS 7.69 vs. 10.46, P = 0.028; SRS 0.83 vs. 1.03, P = 0.019; ODI 12.91 vs. 19.77, P = 0.0016). CONCLUSION Lumbopelvic fixation failure rates were high following ASD correction, and associated with lesser clinical improvements. S2AI screws were more likely to demonstrate loosening, but less commonly associated with rod fractures at the lumbopelvic region.
Collapse
|
10
|
Matsumoto H, Fano AN, Ball J, Roye BD, George A, Garg S, Erickson M, Samdani A, Skaggs D, Roye DP, Vitale MG. Uncorrected Pelvic Obliquity Is Associated With Worse Health-related Quality of Life (HRQoL) in Children and Their Caregivers at the End of Surgical Treatment for Early Onset Scoliosis (EOS). J Pediatr Orthop 2022; 42:e390-e396. [PMID: 35142714 DOI: 10.1097/bpo.0000000000002096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND While largely of concern in nonambulatory patients, pelvic obliquity (PO) can be found in many patients with early onset scoliosis (EOS) and may remain following surgery. However, its association with health-related quality of life (HRQoL) in children and their caregivers at the end of treatment is not well understood. The purpose of this study was to investigate the association between residual PO and HRQoL in children and their caregivers at the end of surgical treatment in ambulatory patients with EOS. METHODS In this retrospective cohort study, a multicenter EOS registry was queried to identify ambulatory patients who underwent definitive posterior spinal fusion (PSF) from 2012 to 2019. Patients with fusions extending to the pelvis were excluded. PO was measured at least 1 year following PSF. HRQoL, Parental Burden, Financial Burden, and Satisfaction were assessed through the 24-Item Early Onset Scoliosis Questionnaire (EOSQ-24) also at a minimum of 1 year following PSF. RESULTS A total of 155 patients (12.5±2.1 y, 73.5% female) were included. Etiology distribution was 30.3% congenital, 12.9% neuromuscular, 21.3% syndromic, and 35.5% idiopathic. In congenital patients, those with residual PO >8 degrees had worse Satisfaction by 23.2 points compared with those with PO ≤8 degrees. In neuromuscular patients, those with residual PO >7 degrees had worse HRQoL by 16.1 points and Parental Burden by 22.3 points compared with their counterparts. In syndromic patients, those with residual PO >8 degrees had worse HRQoL by 14.8 points, Parental Burden by 16.4 points, and Satisfaction by 21.2 points compared with their counterparts. In idiopathic patients, those with >9 degrees of residual PO had worse HRQoL by 15.0 points and Financial Burden by 26.8 points compared with their counterparts. CONCLUSIONS Remaining PO at the end of surgical treatment is associated with worse HRQoL in ambulatory children and their caregivers. These results suggest that correction of PO should remain a primary goal of treatment in patients with EOS undergoing surgery. LEVEL OF EVIDENCE Level II-multicenter retrospective cohort study investigating prognosis.
Collapse
Affiliation(s)
- Hiroko Matsumoto
- Division of Pediatric Orthopaedic Surgery, Department of Orthopaedic Surgery, Columbia University Irving Medical Center
- Department of Epidemiology, Columbia University Mailman School of Public Health
| | - Adam N Fano
- Division of Pediatric Orthopaedic Surgery, Department of Orthopaedic Surgery, Columbia University Irving Medical Center
| | - Jacob Ball
- Division of Pediatric Orthopaedic Surgery, Department of Orthopaedic Surgery, Columbia University Irving Medical Center
| | - Benjamin D Roye
- Division of Pediatric Orthopaedic Surgery, Department of Orthopaedic Surgery, Columbia University Irving Medical Center
- New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY
| | - Ameeka George
- New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY
| | - Sumeet Garg
- Department of Orthopedic Surgery, Children's Hospital Colorado, Aurora, CO
| | - Mark Erickson
- Department of Orthopedic Surgery, Children's Hospital Colorado, Aurora, CO
| | - Amer Samdani
- Department of Neurosurgery, Shriners Hospital for Children, Philadelphia, PA
| | - David Skaggs
- Department of Orthopedic Surgery, Children's Hospital of Los Angeles, Los Angeles, CA
| | - David P Roye
- Division of Pediatric Orthopaedic Surgery, Department of Orthopaedic Surgery, Columbia University Irving Medical Center
| | - Michael G Vitale
- Division of Pediatric Orthopaedic Surgery, Department of Orthopaedic Surgery, Columbia University Irving Medical Center
- New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY
| |
Collapse
|
11
|
Martin CT, Polly DW, Holton KJ, San Miguel-Ruiz JE, Albersheim M, Lender P, Sembrano JN, Hunt MA, Jones KE. Acute failure of S2-alar-iliac screw pelvic fixation in adult spinal deformity: novel failure mechanism, case series, and review of the literature. J Neurosurg Spine 2021; 36:53-61. [PMID: 34479206 DOI: 10.3171/2021.2.spine201921] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 02/16/2021] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Pelvic fixation with S2-alar-iliac (S2AI) screws is an established technique in adult deformity surgery. The authors' objective was to report the incidence and risk factors for an underreported acute failure mechanism of S2AI screws. METHODS The authors retrospectively reviewed a consecutive series of ambulatory adults with fusions extending 3 or more levels, and which included S2AI screws. Acute failure of S2AI screws was defined as occurring within 6 months of the index surgery and requiring surgical revision. RESULTS Failure occurred in 6 of 125 patients (5%) and consisted of either slippage of the rods or displacement of the set screws from the S2AI tulip head, with resultant kyphotic fracture. All failures occurred within 6 weeks postoperatively. Revision with a minimum of 4 rods connecting to 4 pelvic fixation points was successful. Two of 3 (66%) patients whose revision had less fixation sustained a second failure. Patients who experienced failure were younger (56.5 years vs 65 years, p = 0.03). The magnitude of surgical correction was higher in the failure cohort (number of levels fused, change in lumbar lordosis, change in T1-pelvic angle, and change in coronal C7 vertical axis, each p < 0.05). In the multivariate analysis, younger patient age and change in lumbar lordosis were independently associated with increased failure risk (p < 0.05 for each). There was a trend toward the presence of a transitional S1-2 disc being a risk factor (OR 8.8, 95% CI 0.93-82.6). Failure incidence was the same across implant manufacturers (p = 0.3). CONCLUSIONS All failures involved large-magnitude correction and resulted from stresses that exceeded the failure loads of the set plugs in the S2AI tulip, with resultant rod displacement and kyphotic fractures. Patients with large corrections may benefit from 4 total S2AI screws at the time of the index surgery, particularly if a transitional segment is present. Salvage with a minimum of 4 rods and 4 pelvic fixation points can be successful.
Collapse
Affiliation(s)
| | - David W Polly
- 1Department of Orthopaedic Surgery, University of Minnesota; and.,2Department of Neurosurgery, University of Minnesota, Minneapolis, Minnesota
| | - Kenneth J Holton
- 1Department of Orthopaedic Surgery, University of Minnesota; and
| | | | | | - Paul Lender
- 1Department of Orthopaedic Surgery, University of Minnesota; and
| | | | - Matthew A Hunt
- 2Department of Neurosurgery, University of Minnesota, Minneapolis, Minnesota
| | - Kristen E Jones
- 1Department of Orthopaedic Surgery, University of Minnesota; and.,2Department of Neurosurgery, University of Minnesota, Minneapolis, Minnesota
| |
Collapse
|
12
|
Ravindra VM, Mazur MD, Brockmeyer DL, Kraus KL, Ropper AE, Hanson DS, Dahl BT. Clinical Effectiveness of S2-Alar Iliac Screws in Spinopelvic Fixation in Pediatric Neuromuscular Scoliosis: Systematic Literature Review. Global Spine J 2020; 10:1066-1074. [PMID: 32875851 PMCID: PMC7645097 DOI: 10.1177/2192568219899658] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
STUDY DESIGN Systematic literature review. OBJECTIVES To comprehensively review the S2-alar iliac (S2-AI) screw technique for pelvic fixation in pediatric neuromuscular scoliosis. METHODS Articles identified from the PubMed and EMBASE databases were reviewed for relevance and applicability, and the studies were summarized. RESULTS Eight articles met the inclusion criteria. A total of 277 pediatric patients underwent spinopelvic fixation using S2-AI fixation for neuromuscular scoliosis; the mean follow-up was 3 years (range = 0.75-6 years). Six articles had level III evidence (5 retrospective cohort studies, 1 observational study), and 2 articles had level IV evidence (case series). Wound complications occurred in 34 (12.2%) patients. Instrumentation complications occurred in 36 patients (13.0%), including lucency around the screw (6.5%), screw fracture (3.6%), disengaging of the set/screw or rod from the tulip head (2.8%), and screw displacement (0.7%). Three patients (1.1%) required reoperation for instrumentation failures. The overall reoperation rate-including 3 hardware replacements and 3 cases of L5-S1 pseudarthrosis-was 2.1%. The mean Cobb angle correction was 51.4°, and the mean pelvic obliquity correction was 14.8°; deformity correction was maintained at 3- and 5-year follow-ups. There were 10 (3.6%) cases of implant prominence/implant-related pain, 1 case of sacroiliac joint pain (resolved with longer screw placement), and no major neurological or vascular complications secondary to S2-AI screw placement. CONCLUSIONS This review suggests that the use of S2-AI screws in pediatric neuromuscular scoliosis is efficacious with a reasonable safety profile and provides a useful technique for pelvic fixation in children with scoliosis.
Collapse
Affiliation(s)
- Vijay M. Ravindra
- University of Utah, Salt Lake City, UT, USA,Baylor College of Medicine, Houston, TX, USA,Vijay M. Ravindra, Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 N Medical Drive East, Salt Lake City, UT 84132, USA.
| | | | | | | | | | | | | |
Collapse
|
13
|
Mattei TA. S3 Sacral-Alar Iliac Screw: A Salvage Technique for Pelvic Fixation in Complex Deformity Surgery. World Neurosurg 2020; 139:23-30. [PMID: 32194277 DOI: 10.1016/j.wneu.2020.03.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 03/03/2020] [Accepted: 03/04/2020] [Indexed: 01/11/2023]
Abstract
Sacral-alar iliac (SAI) screws constitute a relatively new technique for pelvic fixation. Since their initial description in 2007, SAI screws have gained wide popularity among the spine surgery community. In 2013, we first described the possibility of using both S1 and S2 SAI screws for pelvic fixation in revision surgeries for adult degenerative scoliosis. Although a previous radiological study has suggested the feasibility of S3 and S4 SAI screws, to the best of our knowledge, there has been no report in the literature on the clinical use of such techniques. In this brief technical note, we present the first clinical report of the use of S3 SAI screws as a salvage method for pelvic fixation in a patient with suboptimal anatomy that prevented proper placement of S1 and S2 SAI screws. We also discuss the recommended anatomical entry points and trajectory of such screws.
Collapse
Affiliation(s)
- Tobias A Mattei
- Division of Neurological Surgery, Saint Louis University, Saint Louis University Hospital, St. Louis, Missouri, USA.
| |
Collapse
|
14
|
Morphometric measurement and applicable feature analysis of sacral alar-iliac screw fixation using forward engineering. Arch Orthop Trauma Surg 2020; 140:177-186. [PMID: 31538234 DOI: 10.1007/s00402-019-03257-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Indexed: 10/26/2022]
Abstract
PURPOSE To evaluate S1AI-S4AI screw channels with three-dimensional digital technology simulation analysis and to study the feasibility and applicable features of sacral alar-iliac screw fixation in adults. MATERIALS AND METHODS Forty (20 men and 20 women) normal adult's pelvic CT scan data sets were selected to reconstruct the three-dimensional pelvic model. The ideal S1AI-S4AI screw channels were simulated, followed by precise measurement of their parameters. RESULTS The results showed that there were no significant differences in the transverse angles, sagittal angles, radiuses of the maximal inscribed circles, or lengths of the screw channels in S1AI-S2AI screws between genders (P > 0.05). In contrast, the radiuses of the maximal inscribed circles on the left and right, respectively, were 5.93 ± 1.02 mm and 5.92 ± 1.04 mm in males and 4.64 ± 0.98 mm and 4.59 ± 0.95 mm in females, and there was a significant difference in S3AI screws between genders (P < 0.05). With a radius of 2.50 mm considered to be standard, there were 25 cases (62.5%) with an S4AI screw channel radius ≤ 2.50 mm in 40 adults, and 15 cases (37.5%; 9 males and 6 females) with a radius > 2.50 mm. Furthermore, the transverse angles, the sagittal angles, the lengths of the screw channels, and the radiuses of the maximal inscribed circles were significantly different between genders in 15 cases (P < 0.05). CONCLUSION Only one maximum ideal screw can be placed on one side at a time. With a radius of 2.50 mm considered to be standard, it is feasible to place S1AI-S3AI screws with a radius > 2.50 mm in the entire adult population and S4AI screws with a radius > 2.50 mm in some of the adult population. Furthermore, preoperative three-dimensional reconstruction and three-matic research software can effectively simulate the sacral alar-iliac screw channels, and they can provide accurate data for clinical applications.
Collapse
|
15
|
Cunningham BW, Sponseller PD, Murgatroyd AA, Kikkawa J, Tortolani PJ. A comprehensive biomechanical analysis of sacral alar iliac fixation: an in vitro human cadaveric model. J Neurosurg Spine 2019; 30:367-375. [PMID: 30611149 DOI: 10.3171/2018.8.spine18328] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 08/27/2018] [Indexed: 11/06/2022]
Abstract
In BriefIn this in vitro investigation, we compared the multidirectional flexibility properties of sacral alar iliac fixation with conventional methods of sacral and sacroiliac fixation using nondestructive and destructive investigative methods. The study demonstrated that S1-2 sacral fixation alone significantly increases sacroiliac motion under all loading modalities, while sacral alar iliac fixation reduced motion in axial rotation at the sacroiliac joint and offers potential advantages of a lower instrumentation profile and ease of assembly compared to conventional sacroiliac screw instrumentation.
Collapse
Affiliation(s)
- Bryan W Cunningham
- 1MedStar Musculoskeletal Education and Research Institute, Department of Orthopaedic Surgery, MedStar Union Memorial Hospital
| | - Paul D Sponseller
- 2Department of Orthopedic Surgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland; and
| | - Ashley A Murgatroyd
- 1MedStar Musculoskeletal Education and Research Institute, Department of Orthopaedic Surgery, MedStar Union Memorial Hospital
| | - Jun Kikkawa
- 3Department of Orthopedic Surgery, Saitama Medical University, Saitama, Japan
| | - P Justin Tortolani
- 1MedStar Musculoskeletal Education and Research Institute, Department of Orthopaedic Surgery, MedStar Union Memorial Hospital
| |
Collapse
|
16
|
El Dafrawy MH, Raad M, Okafor L, Kebaish KM. Sacropelvic Fixation: A Comprehensive Review. Spine Deform 2019; 7:509-516. [PMID: 31202365 DOI: 10.1016/j.jspd.2018.11.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 11/09/2018] [Accepted: 11/11/2018] [Indexed: 11/18/2022]
Abstract
Sacropelvic fixation is indicated in various clinical settings, most notably long spinal arthrodesis, reduction of high-grade spondylolisthesis, and complex sacral fractures. The sacropelvis is characterized by complex regional anatomy and poor bone quality. These factors make achieving solid fusion across the lumbosacral junction challenging. However, a better understanding of spinal biomechanics at that level has led to much higher fusion rates than those of the past. The newer fixation techniques are biomechanically superior to previous methods mainly because they achieve bony purchase anterior to the pivot point-first described by McCord et al. in 1994. Today, the two most widely used fixation techniques are iliac screws and S2-alar-iliac screws. Although these techniques are associated with very high rates of fusion, instrumentation-related pain and reoperation remain problematic. This review provides an overview of the regional anatomy and biomechanics at the lumbosacral junction, as well as a summary of fixation techniques with an emphasis on the most widely used techniques today. LEVEL OF EVIDENCE: IV.
Collapse
Affiliation(s)
- Mostafa H El Dafrawy
- Department of Orthopaedic Surgery, Johns Hopkins Hospital, 1800 Orleans St, Baltimore, MD 21287, USA
| | - Micheal Raad
- Department of Orthopaedic Surgery, Johns Hopkins Hospital, 1800 Orleans St, Baltimore, MD 21287, USA
| | - Louis Okafor
- Department of Orthopaedic Surgery, Johns Hopkins Hospital, 1800 Orleans St, Baltimore, MD 21287, USA
| | - Khaled M Kebaish
- Department of Orthopaedic Surgery, Johns Hopkins Hospital, 1800 Orleans St, Baltimore, MD 21287, USA.
| |
Collapse
|
17
|
Don't You Wish You Had Fused to the Pelvis the First Time: A Comparison of Reoperation Rate and Correction of Pelvic Obliquity. Spine (Phila Pa 1976) 2019; 44:E465-E469. [PMID: 30299416 DOI: 10.1097/brs.0000000000002888] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN A multicenter retrospective study. OBJECTIVE The aim of this study was to compare pelvic obliquity correction and reoperation rate in neuromuscular scoliosis patients who had their pelvis included in a posterior spinal fusion (pelvic fusion, PF) at their index procedure versus revision procedures. SUMMARY OF BACKGROUND DATA There is limited information on outcomes specific to fusing to the pelvis for neuromuscular scoliosis in a revision operation versus index surgery. METHODS Charts and radiographs were reviewed of patients with PF for neuromuscular scoliosis from January 2003 to August 2015 at four high-volume pediatric spine centers with >2 year follow-up. RESULTS Two hundred eighty-five patients met inclusion criteria; 271 had PF done at index surgery and 14 had PF done during revision surgery. Before index procedure, there were no significant differences in Cobb angle (P = 0.13). Before PF, there was no difference in pelvic obliquity (P = 0.26). At the time of fusion to the pelvis, estimated blood loss (P = 0.23) and operative time (P = 0.43) did not differ between index and revision groups. Percent correction in pelvic obliquity was similar for both groups (P = 0.72). Overall, 69 patients had complications requiring return to the operating room. Excluding the revision surgery for inclusion of the pelvis for the revision group, there was still a lower reoperation rate with index PF (22.9%, n = 62/271) than revision PF (50.0%, n = 7/14) (P = 0.02). Implant failures were significantly higher in the revision group (index = 7.4%, 20/271; revision = 42.9%, 6/14; P < 0.001). CONCLUSION PF at the index spinal fusion led to similar correction of pelvic obliquity with approximately half the reoperation rate compared with PF at a revision surgery. Operative time and blood loss were similar between index and revision spinal fusion. LEVEL OF EVIDENCE 4.
Collapse
|
18
|
Cottrill E, Margalit A, Brucker C, Sponseller PD. Comparison of Sacral-Alar-Iliac and Iliac-Only Methods of Pelvic Fixation in Early-Onset Scoliosis at 5.8 Years' Mean Follow-up. Spine Deform 2019; 7:364-370. [PMID: 30660234 DOI: 10.1016/j.jspd.2018.08.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 07/02/2018] [Accepted: 08/12/2018] [Indexed: 11/24/2022]
Abstract
STUDY DESIGN Retrospective. OBJECTIVE Compare clinical outcomes in early-onset scoliosis (EOS) patients treated with sacral-alar-iliac (SAI) versus iliac-only methods of pelvic fixation at two years' minimum follow-up. SUMMARY OF BACKGROUND DATA Pelvic fixation in EOS is challenged by poor bone, anchor migration, and displacement. The long-term outcomes of SAI fixation in EOS is unknown. METHODS We retrospectively reviewed EOS patients in a single center from 2000 to 2017. Inclusion criteria were posterior spinal instrumentation with pelvic fixation before age 10 and 2 years' minimum follow-up. Clinical and radiographic data were analyzed using chi-squared and Student t tests (significance defined as p <.05). RESULTS Seven subjects were included in the iliac-only fixation group (Galveston technique = 2, iliac screws = 5) and 17 in the SAI group. For the iliac-only group (mean follow-up = 6.8 years), pelvic obliquity improved from a mean of 18° at initial presentation to 11° at first instrumentation (p = .096), to 9° at end follow-up (p = .060), whereas the major curve improved correspondingly from a mean of 84° to 50° (p = .002) to 39° (p = .006). For the SAI group (mean follow-up = 5.5 years) at the same time points, pelvic obliquity improved from a mean of 25° to 6° (p <.001) to 5° (p <.001), whereas the major curve improved from a mean of 83° to 38° (p <.001) to 29° (p <.001). SAI fixation was associated with fewer complications (11 complications in 17 patients) compared to iliac-only fixation (10 complications in 7 patients) (p = .04). Neither method was associated with pelvic growth disturbances or neurologic deficits. CONCLUSIONS In EOS patients at 2 years' minimum (5.8 years' mean) follow-up, both SAI and iliac-only methods corrected major curve, only SAI fixation corrected pelvic obliquity, and neither was associated with pelvic growth disturbances. SAI fixation was also associated with fewer complications. These findings may be due to the length and direction of the SAI anchors and abutment on the iliac cortex. LEVEL OF EVIDENCE Level III.
Collapse
Affiliation(s)
- Ethan Cottrill
- Department of Orthopaedic Surgery, The Johns Hopkins Hospital, 601 N. Caroline Street, Baltimore, MD 21287, USA.
| | - Adam Margalit
- Department of Orthopaedic Surgery, The Johns Hopkins Hospital, 601 N. Caroline Street, Baltimore, MD 21287, USA
| | - Cameron Brucker
- Department of Orthopaedic Surgery, The Johns Hopkins Hospital, 601 N. Caroline Street, Baltimore, MD 21287, USA
| | - Paul D Sponseller
- Department of Orthopaedic Surgery, The Johns Hopkins Hospital, 601 N. Caroline Street, Baltimore, MD 21287, USA
| |
Collapse
|
19
|
Ramchandran S, George S, Asghar J, Shufflebarger H. Anatomic Trajectory for Iliac Screw Placement in Pediatric Scoliosis and Spondylolisthesis: An Alternative to S2-Alar Iliac Portal. Spine Deform 2019; 7:286-292. [PMID: 30660223 DOI: 10.1016/j.jspd.2018.08.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 08/04/2018] [Accepted: 08/05/2018] [Indexed: 12/18/2022]
Abstract
STUDY DESIGN Single-center retrospective study. OBJECTIVE To analyze two-year postoperative outcomes following spinopelvic fixation in pediatric patients using the anatomic trajectory (AT) portal for iliac screws. SUMMARY Iliac fixation is crucial in situations requiring fusion to sacrum. Challenges include complex anatomy, pelvic deformation, severe deformity, and previous surgery. The PSIS portal requires significant dissection, rod connectors, and complex bends. The SAI portal requires navigating the screw across the SI joint to the ilium. The anatomic trajectory (AT), first reported in 2009, is between the PSIS and SAI portal, without prominence, connectors, or complex bends. METHODS Fifty-four patients aged ≤18 years requiring instrumentation to the Ilium with minimum follow-up of two years (mean 44 months) were clinically and radiographically evaluated. Changes in coronal curve magnitude and pelvic obliquity were assessed using paired t test for patients with cerebral palsy. Spondylolisthesis reduction was assessed in patients with moderate- to high-grade spondylolisthesis (Meyerding grade 3 and 4). RESULTS A total of 108 iliac screws were inserted using AT portal in 54 patients. Twenty-eight neuromuscular and syndromic patients had an initial mean coronal curve of 85° corrected to 23° at two years (p < .001) and a pelvic obliquity of 22° corrected to 4° (p < .001). Twenty patients with moderate- to high-grade spondylolisthesis treated with reduction and interbody fixation improved significantly with respect to their slip angles (7° ± 14.7° to -7.9° ± 6.1°, p = .003). In the neuromuscular group, two surgical site infections occurred, two had implant fractures, and 12 had asymptomatic iliac screw loosening, none requiring revision. In the spondylolisthesis group, there were no neurologic complications and one had prominent screw requiring removal. Of 108 iliac screws, 2 rod connectors were employed. CONCLUSION Iliac screw insertion using the AT portal is a safe and effective method of pelvic fixation in pediatric patients with satisfactory radiographic correction and minimal complications. LEVEL OF EVIDENCE Level 4.
Collapse
Affiliation(s)
- Subaraman Ramchandran
- Center for Spinal Disorders, Department of Orthopedic Surgery, Nicklaus Children's Hospital, 3100 S.W. 62nd Ave, Miami, FL 33155, USA.
| | - Stephen George
- Center for Spinal Disorders, Department of Orthopedic Surgery, Nicklaus Children's Hospital, 3100 S.W. 62nd Ave, Miami, FL 33155, USA
| | - Jahangir Asghar
- Center for Spinal Disorders, Department of Orthopedic Surgery, Nicklaus Children's Hospital, 3100 S.W. 62nd Ave, Miami, FL 33155, USA
| | - Harry Shufflebarger
- Center for Spinal Disorders, Department of Orthopedic Surgery, Nicklaus Children's Hospital, 3100 S.W. 62nd Ave, Miami, FL 33155, USA
| |
Collapse
|
20
|
Nguyen JH, Buell TJ, Wang TR, Mullin JP, Mazur MD, Garces J, Taylor DG, Yen CP, Shaffrey CI, Smith JS. Low rates of complications after spinopelvic fixation with iliac screws in 260 adult patients with a minimum 2-year follow-up. J Neurosurg Spine 2019; 30:635-643. [PMID: 30717036 DOI: 10.3171/2018.9.spine18239] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 09/26/2018] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Recent literature describing complications associated with spinopelvic fixation with iliac screws in adult patients has been limited but has suggested high complication rates. The authors' objective was to report their experience with iliac screw fixation in a large series of patients with a 2-year minimum follow-up. METHODS Of 327 adult patients undergoing spinopelvic fixation with iliac screws at the authors' institution between 2010 and 2015, 260 met the study inclusion criteria (age ≥ 18 years, first-time iliac screw placement, and 2-year minimum follow-up). Patients with active spinal infection were excluded. All iliac screws were placed via a posterior midline approach using fluoroscopic guidance. Iliac screw heads were deeply recessed into the posterior superior iliac spine. Clinical and radiographic data were obtained and analyzed. RESULTS Twenty patients (7.7%) had iliac screw-related complication, which included fracture (12, 4.6%) and/or screw loosening (9, 3.5%). No patients had iliac screw head prominence that required revision surgery or resulted in pain, wound dehiscence, or poor cosmesis. Eleven patients (4.2%) had rod or connector fracture below S1. Overall, 23 patients (8.8%) had L5-S1 pseudarthrosis. Four patients (1.5%) had fracture of the S1 screw. Seven patients (2.7%) had wound dehiscence (unrelated to the iliac screw head) or infection. The rate of reoperation (excluding proximal junctional kyphosis) was 17.7%. On univariate analysis, an iliac screw-related complication rate was significantly associated with revision fusion (70.0% vs 41.2%, p = 0.013), a greater number of instrumented vertebrae (mean 12.6 vs 10.3, p = 0.014), and greater postoperative pelvic tilt (mean 27.7° vs 23.2°, p = 0.04). Lumbosacral junction-related complications were associated with a greater mean number of instrumented vertebrae (12.6 vs 10.3, p = 0.014). Reoperation was associated with a younger mean age at surgery (61.8 vs 65.8 years, p = 0.014), a greater mean number of instrumented vertebrae (12.2 vs 10.2, p = 0.001), and longer clinical and radiological mean follow-up duration (55.8 vs 44.5 months, p < 0.001; 55.8 vs 44.6 months, p < 0.001, respectively). On multivariate analysis, reoperation was associated with longer clinical follow-up (p < 0.001). CONCLUSIONS Previous studies on iliac screw fixation have reported very high rates of complications and reoperation (as high as 53.6%). In this large, single-center series of adult patients, iliac screws were an effective method of spinopelvic fixation that had high rates of lumbosacral fusion and far lower complication rates than previously reported. Collectively, these findings argue that iliac screw fixation should remain a favored technique for spinopelvic fixation.
Collapse
|
21
|
Anari JB, Cahill PJ, Flynn JM, Spiegel DA, Baldwin KD. Intra-operative computed tomography guided navigation for pediatric pelvic instrumentation: A technique guide. World J Orthop 2018; 9:185-189. [PMID: 30364843 PMCID: PMC6198293 DOI: 10.5312/wjo.v9.i10.185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 07/29/2018] [Accepted: 08/05/2018] [Indexed: 02/06/2023] Open
Abstract
Pelvic instrumentation for neuromuscular scoliosis has been part of neuromuscular scoliosis surgery since the era of the Luque Galveston construct. Unit Rod (Medtronic Sofamor-Danek, Nashville, TN) instrumentation brought with it the concept of cantilever correction by placing the implants in the pelvis and then gradually bringing the rod to the spine by sequentially tightening the sublaminar wires, with the goal of creating a level pelvis over a straight spine. More recently surgeons have utilized pedicle screw constructs in which the corrective strategies have varied. Challenges with pelvic fixation using iliac screws linked to the spinal rod have led to the development of the S2-alar-iliac technique (S2AI) in which the spinal rod connects to the pelvic screw. The screw is placed in the S2 ala, crosses the sacro-iliac joint and into the ilium through a large column of supra-acetabular bone. This column is the same area used for anterior inferior iliac spine external fixation frames used in trauma surgery. S2AI screw placement can be technically difficult and can require experienced radiology technologists to provide the appropriate views. Additionally, although the technique was originally described being placed via freehand technique with intra-operative flouroscopy, the freehand technique suffers from the anatomic anomalies present in the pelvis in neuromuscular scoliosis. As such, we prefer to place them using intra-operative navigation for all pediatric spinal deformity cases. Below in detail we report our intra-operative technique and an illustrative case example.
Collapse
Affiliation(s)
- Jason B Anari
- Department of Orthopaedic Surgery, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Patrick J Cahill
- Department of Orthopaedic Surgery, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - John M Flynn
- Department of Orthopaedic Surgery, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - David A Spiegel
- Department of Orthopaedic Surgery, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Keith D Baldwin
- Department of Orthopaedic Surgery, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, United States
| |
Collapse
|
22
|
Lin JD, Tan LA, Wei C, Shillingford JN, Laratta JL, Lombardi JM, Kim YJ, Lehman RA, Lenke LG. The posterior superior iliac spine and sacral laminar slope: key anatomical landmarks for freehand S2-alar-iliac screw placement. J Neurosurg Spine 2018; 29:429-434. [PMID: 30052147 DOI: 10.3171/2018.3.spine171374] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The S2-alar-iliac (S2AI) screw is an increasingly popular method for spinopelvic fixation. The technique of freehand S2AI screw placement has been recently described. The purpose of this study was to demonstrate, through a CT imaging study of patients with spinal deformity, that screw trajectories based on the posterior superior iliac spine (PSIS) and sacral laminar slope result in reliable freehand S2AI trajectories that traverse safely above the sciatic notch. METHODS Fifty consecutive patients (age ≥ 18 years) who underwent primary spinal deformity surgery were included in the study. Simulated S2AI screw trajectories were analyzed with 3D visualization software. The cephalocaudal coordinate for the starting point was 15 mm cephalad to the PSIS. The mediolateral coordinate for the starting point was in line with the lateral border of the dorsal foramina. The cephalocaudal screw trajectory was perpendicular to the sacral laminar slope. Screw trajectories, lengths, and distance above the sciatic notch were measured. RESULTS The mean sagittal screw angle (cephalocaudal angulation) was 44.0° ± 8.4° and the mean transverse angle (mediolateral angulation) was 37.3° ± 4.3°. The mean starting point was 5.9 ± 5.8 mm distal to the caudal border of the S1 foramen. The mean screw length was 99.9 ± 18.6 mm. Screw trajectories were on average 8.5 ± 4.3 mm above the sciatic notch. A total of 97 of 100 screws were placed above the sciatic notch. In patients with transitional lumbosacral anatomy, the starting point on the lumbarized/sacralized side was 3.4 mm higher than on the contralateral unaffected side. CONCLUSIONS The PSIS and sacral laminar slope are two important anatomical landmarks for freehand S2AI screw placement.
Collapse
Affiliation(s)
- James D Lin
- 1Department of Orthopedic Surgery, Columbia University Medical Center, The Spine Hospital at NewYork-Presbyterian/Allen, New York, New York
| | - Lee A Tan
- 2Department of Neurological Surgery, University of California San Francisco Medical Center, San Francisco, California; and
| | - Chao Wei
- 3Department of Spine Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, People's Republic of China
| | - Jamal N Shillingford
- 1Department of Orthopedic Surgery, Columbia University Medical Center, The Spine Hospital at NewYork-Presbyterian/Allen, New York, New York
| | - Joseph L Laratta
- 1Department of Orthopedic Surgery, Columbia University Medical Center, The Spine Hospital at NewYork-Presbyterian/Allen, New York, New York
| | - Joseph M Lombardi
- 1Department of Orthopedic Surgery, Columbia University Medical Center, The Spine Hospital at NewYork-Presbyterian/Allen, New York, New York
| | - Yongjung J Kim
- 1Department of Orthopedic Surgery, Columbia University Medical Center, The Spine Hospital at NewYork-Presbyterian/Allen, New York, New York
| | - Ronald A Lehman
- 1Department of Orthopedic Surgery, Columbia University Medical Center, The Spine Hospital at NewYork-Presbyterian/Allen, New York, New York
| | - Lawrence G Lenke
- 1Department of Orthopedic Surgery, Columbia University Medical Center, The Spine Hospital at NewYork-Presbyterian/Allen, New York, New York
| |
Collapse
|