A novel mathematical model of the sagittal spine: application to pedicle subtraction osteotomy for correction of fixed sagittal deformity

Abstract Minimally invasive surgery (MIS) approaches for the correction of adult spinal deformity have gained popularity in the past decade. MIS approaches can result in decreased hospitalization times and decreased morbidity. However, compared to open techniques, MIS approaches are challenging in the setting of fixed sagittal deformity and strategic surgical staging. Combined MIS and miniopen techniques are described as “hybrid” techniques. We report on the surgical approach for a fixed sagittal deformity using both MIS and miniopen techniques, specifically a miniopen pedicle subtraction osteotomy (PSO) and an anterior column release (ACR). The patient gave written informed consent for surgical treatment; institutional review board approval was not required. The patient first underwent the placement of percutaneous modular pedicle screws from T12 to the pelvis as well as a mini-PSO across the previously fused L5 vertebral body, with the placement of a temporary rod. The following day, the patient underwent lateral transpsoas interbody fusion and ACR at L2/3; a percutaneous rod was then passed from T12 to the pelvis for segmental fixation. The patient recovered well and was discharged home without complication 6 d after the initial day of surgery. The combined use of surgical staging and traditional open techniques in a selective, minimalistic fashion and adherence to minimally invasive principles provide for a powerful set of surgical techniques that capitalize on less invasive approaches to deformity management. Used with permission from Barrow Neurological Institute, Phoenix, Arizona.

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A novel approach to sagittal balance restoration following iatrogenic sacral fracture and resulting sacral kyphotic deformity

Journal of Neurosurgery Spine ◽

10.3171/spi.2007.6.4.15 ◽

2007 ◽

Vol 6 (4) ◽

pp. 368-372 ◽

Cited By ~ 21

Author(s):

Patrick C. Hsieh ◽

Stephen L. Ondra ◽

Robert J. Wienecke ◽

Brian A. O'Shaughnessy ◽

Tyler R. Koski

Keyword(s):

Sagittal Balance ◽

Pelvic Incidence ◽

Morphological Characteristics ◽

Pedicle Subtraction Osteotomy ◽

Sacral Fracture ◽

Novel Approach ◽

Sagittal Spinal Alignment ◽

Fixed Parameter ◽

Lumbar Hyperlordosis ◽

Sagittal Deformity

✓The authors describe the use of sacral pedicle subtraction osteotomy (PSO) with multiple sacral alar osteotomies for the correction of sacral kyphosis and pelvic incidence and for achieving sagittal balance correction in cases of fixed sagittal deformity after a sacral fracture. In this paper, the authors report on a novel technique using a series of sacral osteotomies and a sacral PSO to correct a fixed sagittal deformity in a patient with a sacral fracture that had healed in a kyphotic position. The patient sustained this fracture after a previous surgery for multilevel instrumented fusion. Preoperative and postoperative radiographic studies are reviewed and the clinical course and outcome are presented. Experts agree that the pelvic incidence is a fixed parameter that dictates the morphological characteristics of the pelvis and affects spinopelvic orientation and sagittal spinal alignment. An increased pelvic incidence is associated with a higher degree of spondylolisthesis in the lumbosacral junction, and increased shear forces across this junction. The authors demonstrate that the pelvic incidence can be altered and corrected with a series of sacral osteotomies to improve sacral kyphosis, compensatory lumbar hyperlordosis, and sagittal balance.

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P68. Thoracic Pedicle Subtraction Osteotomy for Fixed Sagittal Deformity: Clinical and Radiographic Outcomes

The Spine Journal ◽

10.1016/j.spinee.2007.07.274 ◽

2007 ◽

Vol 7 (5) ◽

pp. 114S

Author(s):

O'Shaughnessy Brian ◽

Tim Kuklo ◽

Benson Yang ◽

Tyler Koski ◽

Stephen Ondra

Keyword(s):

Pedicle Subtraction Osteotomy ◽

Radiographic Outcomes ◽

Sagittal Deformity

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Surgical management of global sagittal deformity in ankylosing spondylitis

Neurosurgical FOCUS ◽

10.3171/foc/2008/24/1/e8 ◽

2008 ◽

Vol 24 (1) ◽

pp. E8 ◽

Cited By ~ 26

Author(s):

Charles A. Sansur ◽

Kai-Ming G. Fu ◽

Rod J. Oskouian ◽

Jay Jagannathan ◽

Charles Kuntz ◽

...

Keyword(s):

Ankylosing Spondylitis ◽

Preoperative Planning ◽

Sagittal Plane ◽

Axial Skeleton ◽

Pedicle Subtraction Osteotomy ◽

Review Article ◽

Cervicothoracic Junction ◽

Plane Deformity ◽

Sagittal Deformity ◽

Review Current

✓ Ankylosing spondylitis (AS) is an inflammatory rheumatic disease whose primary effect is on the axial skeleton, causing sagittal-plane deformity at both the thoracolumbar and cervicothoracic junctions. In the present review article the authors discuss current concepts in the preoperative planning of patients with AS. The authors also review current techniques used to treat sagittal-plane deformity, focusing on pedicle subtraction osteotomy at the thoracolumbar junction, as well as cervical extension osteotomy at the cervicothoracic junction.

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Mathematical Calculation of Pedicle Subtraction Osteotomy Size to Allow Precision Correction of Fixed Sagittal Deformity

Spine ◽

10.1097/01.brs.0000247950.02886.e5 ◽

2006 ◽

Vol 31 (25) ◽

pp. E973-E979 ◽

Cited By ~ 90

Author(s):

Stephen L. Ondra ◽

Shaden Marzouk ◽

Tyler Koski ◽

Fernando Silva ◽

Sean Salehi

Keyword(s):

Pedicle Subtraction Osteotomy ◽

Mathematical Calculation ◽

Sagittal Deformity

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A Method for Calculating the Exact Angle Required during Pedicle Subtraction Osteotomy for Fixed Sagittal Deformity: Comparison with the Trigonometric Method

Operative Neurosurgery ◽

10.1227/01.neu.0000232628.46247.15 ◽

2006 ◽

Vol 59 ◽

pp. ONS-458-ONS-463 ◽

Cited By ~ 5

Author(s):

Benson P. Yang ◽

Stephen L. Ondra

Keyword(s):

Pedicle Subtraction Osteotomy ◽

Sagittal Deformity

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Hybrid Anterior Column Realignment – Pedicle Subtraction Osteotomy for Severe Rigid Sagittal Deformity

World Neurosurgery ◽

10.1016/j.wneu.2021.04.028 ◽

2021 ◽

Author(s):

Saeed S. Sadrameli ◽

Vitaliy Davidov ◽

Jonathan J. Lee ◽

Meng Huang ◽

Dominic J. Kizek ◽

...

Keyword(s):

Pedicle Subtraction Osteotomy ◽

Anterior Column ◽

Sagittal Deformity

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P92. Preventing rod failure in pedicle subtraction osteotomy revision surgeries for sagittal deformity with a satellite rod technique

The Spine Journal ◽

10.1016/j.spinee.2019.05.517 ◽

2019 ◽

Vol 19 (9) ◽

pp. S201

Author(s):

Adam M. Wegner ◽

Alexander T. Yahanda ◽

Pope Rodnoi ◽

Eric O. Klineberg ◽

Munish C. Gupta

Keyword(s):

Pedicle Subtraction Osteotomy ◽

Sagittal Deformity

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Asymmetrical pedicle subtraction osteotomy for correction of concurrent sagittal-coronal imbalance in adult spinal deformity: a comparative analysis

Journal of Neurosurgery Spine ◽

10.3171/2020.5.spine20445 ◽

2020 ◽

Vol 33 (6) ◽

pp. 822-829

Author(s):

Darryl Lau ◽

Alexander F. Haddad ◽

Vedat Deviren ◽

Christopher P. Ames

Keyword(s):

Spinal Deformity ◽

Adult Spinal Deformity ◽

Vertical Axis ◽

Pedicle Subtraction Osteotomy ◽

Sagittal Imbalance ◽

Sagittal Vertical Axis ◽

Coronal Imbalance ◽

Significant Correction ◽

Sagittal Deformity

OBJECTIVERigid multiplanar thoracolumbar adult spinal deformity (ASD) cases are challenging and many require a 3-column osteotomy (3CO), specifically asymmetrical pedicle subtraction osteotomy (APSO). The outcomes and additional risks of performing APSO for the correction of concurrent sagittal-coronal deformity have yet to be adequately studied.METHODSThe authors performed a retrospective review of all ASD patients who underwent 3CO during the period from 2006 to 2019. All cases involved either isolated sagittal deformity (patients underwent standard PSO) or concurrent sagittal-coronal deformity (coronal vertical axis [CVA] ≥ 4.0 cm; patients underwent APSO). Perioperative and 2-year follow-up outcomes were compared between patients with isolated sagittal imbalance who underwent PSO and those with concurrent sagittal-coronal imbalance who underwent APSO.RESULTSA total of 390 patients were included: 338 who underwent PSO and 52 who underwent APSO. The mean patient age was 64.6 years, and 65.1% of patients were female. APSO patients required significantly more fusions with upper instrumented vertebrae (UIV) in the upper thoracic spine (63.5% vs 43.3%, p = 0.007). Radiographically, APSO patients had greater deformity with more severe preoperative sagittal and coronal imbalance: sagittal vertical axis (SVA) 13.0 versus 10.7 cm (p = 0.042) and CVA 6.1 versus 1.2 cm (p < 0.001). In APSO cases, significant correction and normalization were achieved (SVA 13.0–3.1 cm, CVA 6.1–2.0 cm, lumbar lordosis [LL] 26.3°–49.4°, pelvic tilt [PT] 38.0°–20.4°, and scoliosis 25.0°–10.4°, p < 0.001). The overall perioperative complication rate was 34.9%. There were no significant differences between PSO and APSO patients in rates of complications (overall 33.7% vs 42.3%, p = 0.227; neurological 5.9% vs 3.9%, p = 0.547; medical 20.7% vs 25.0%, p = 0.482; and surgical 6.5% vs 11.5%, p = 0.191, respectively). However, the APSO group required significantly longer stays in the ICU (3.1 vs 2.3 days, p = 0.047) and hospital (10.8 vs 8.3 days, p = 0.002). At the 2-year follow-up, there were no significant differences in mechanical complications, including proximal junctional kyphosis (p = 0.352), pseudarthrosis (p = 0.980), rod fracture (p = 0.852), and reoperation (p = 0.600).CONCLUSIONSASD patients with significant coronal imbalance often have severe concurrent sagittal deformity. APSO is a powerful and effective technique to achieve multiplanar correction without higher risk of morbidity and complications compared with PSO for sagittal imbalance. However, APSO is associated with slightly longer ICU and hospital stays.

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