Hybrid versus Total Sublaminar Wires in Patients With Spinal Muscular Atrophy Undergoing Scoliosis Surgery

Abstract BackgroundEarly versions of spinal muscular atrophy (SMA) scoliosis correction surgeries often involved sublaminar devices. Recently the utilization of pedicle screw is gaining much popularity. Pedicle screw generally believed to provide additional deformity correction, but pedicle size and rotational deformity limit the application of pedicle screw in the thoracic spine, resulting in a hybrid construct of the pedicle screw and sublaminar wire. Studies of the efficacy of hybrid instrumentation in SMA scoliosis is often limited by the scarcity of the disease itself. In this study, we aimed to compare the surgical outcome of using hybrid constructs of the pedicle screw and sublaminar wire and that of sublaminar wire alone in patients with SMA scoliosis.MethodsWe retrospectively reviewed the clinical records and radiographic assessments of patients with SMA scoliosis who underwent corrective surgery between 1993 and 2015. The radiographic assessments included the deformity correction and the progressive change of major curve angle, pelvic tilt (PT) and coronal balance (CB). The correction of deformities was observed postoperatively and at the patient’s 2-year follow-up to test the efficacy of each type of constructs.ResultsThirty-three patients were included in this study. There were 14 and 19 patients in the wiring and the hybrid construct groups, respectively. The hybrid construct demonstrated a higher major curve angle correction (50.5° ± 11.2° vs. 36.4° ± 8.4°, p < 0.001), a higher apical vertebral rotation correction (10.6° ± 3.9° vs. 4.8° ± 2.6°, p < 0.001), and reduced the progression of major curve angle after the 2-year follow-up (5.1° ± 2.9° vs. 8.7° ± 4.8°, p < 0.001). A moderate correlation was observed between the magnitude of correction of apical vertebral rotation angle and major curve (r = 0.528, p = 0.002).ConclusionThis study demonstrated that hybrid instrumentation can provide a greater magnitude of correction in major curve and apical rotation, as well as less major curve progression in comparison with sublaminar wire in patients with SMA scoliosis.Level of evidence III

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Hybrid versus total sublaminar wires in patients with spinal muscular atrophy undergoing scoliosis surgery

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04737-0 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Shih-Hsiang Chou ◽

Wen-Wei Li ◽

Cheng-Chang Lu ◽

Kun-Ling Lin ◽

Sung-Yen Lin ◽

...

Keyword(s):

Spinal Muscular Atrophy ◽

Muscular Atrophy ◽

Deformity Correction ◽

Pedicle Screws ◽

Vertebral Rotation ◽

Major Curve ◽

Apical Vertebral Rotation ◽

Hybrid Instrumentation ◽

Hybrid Construct

Abstract Background Early versions of spinal muscular atrophy (SMA) scoliosis correction surgery often involved sublaminar devices. Recently, the utilization of pedicle screws has gained much popularity. Pedicle screws are generally believed to provide additional deformity correction, but pedicle size and rotational deformity limit their application in the thoracic spine, resulting in a hybrid construct involving pedicle screws and sublaminar wire. Studies of the efficacy of hybrid instrumentation in SMA scoliosis are often limited by the scarcity of the disease itself. In this study, we aimed to compare the surgical outcomes between hybrid constructs involving pedicle screws and sublaminar wire and sublaminar wire alone in patients with SMA scoliosis. Methods We retrospectively reviewed the clinical records and radiographic assessments of patients with SMA scoliosis who underwent corrective surgery between 1993 and 2017. The radiographic assessments included deformity correction and progressive changes in the major curve angle, pelvic tilt (PT) and coronal balance (CB). The correction of deformities was observed postoperatively and at the patient’s 2-year follow-up to test the efficacy of each type of construct. Results Thirty-three patients were included in this study. There were 14 and 19 patients in the wiring and hybrid construct groups, respectively. The hybrid construct group demonstrated a higher major curve angle correction (50.5° ± 11.2° vs. 36.4° ± 8.4°, p < 0.001), a higher apical vertebral rotation correction (10.6° ± 3.9° vs. 4.8° ± 2.6°, p < 0.001), and a reduced progression of the major curve angle at the 2-year follow-up (5.1° ± 2.9° vs. 8.7° ± 4.8°, p < 0.001). A moderate correlation was observed between the magnitude of correction of the apical vertebral rotation angle and the major curve (r = 0.528, p = 0.002). Conclusion This study demonstrated that hybrid instrumentation can provide a greater magnitude of correction in major curve and apical rotation as well as less major curve progression than sublaminar wire instrumentation alone in patients with SMA scoliosis. Level of evidence III

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Incidence and Radiological Risk Factors of Proximal Junctional Kyphosis in Adolescent Idiopathic Scoliosis Following Pedicle Screw Instrumentation with Rod Derotation and Direct Vertebral Rotation: A Minimum 5-Year Follow-Up Study

Journal of Clinical Medicine ◽

10.3390/jcm10225351 ◽

2021 ◽

Vol 10 (22) ◽

pp. 5351

Author(s):

Hong Jin Kim ◽

Jae Hyuk Yang ◽

Dong-Gune Chang ◽

Se-Il Suk ◽

Seung Woo Suh ◽

...

Keyword(s):

Risk Factors ◽

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Pedicle Screw ◽

Deformity Correction ◽

Vertebral Rotation ◽

Proximal Junctional Kyphosis ◽

Pedicle Screw Instrumentation ◽

Junctional Kyphosis

Several studies have reported incidence and risk factors for the development of proximal junctional kyphosis (PJK) in patients with adolescent idiopathic scoliosis (AIS). However, there is little information regarding long-term follow-up after pedicle screw instrumentation (PSI) with rod derotation (RD) and direct vertebral rotation (DVR). Sixty-nine AIS patients who underwent deformity correction using PSI with RD and DVR were retrospectively analyzed in two groups according to the occurrence of PJK, with a minimum five-year follow-up, including a non-PJK group (n = 62) and PJK group (n = 7). Radiological parameters were evaluated at preoperative, postoperative, and last follow-up. Incidence for PJK was 10.1% (7/69 patients), with a mean 9.4-year follow-up period. The thoracolumbar/lumbar curve (TL/L curve) was proportionally higher in the PJK group. The proximal compensatory curve was significantly lower in the PJK group than in the non-PJK group preoperatively (p = 0.027), postoperatively (p = 0.001), and at last follow-up (p = 0.041). The development of PJK was associated with the TL/L curve pattern, lower preoperative proximal compensatory curve, and over-correction of the proximal curve for PSI with RD and DVR. Therefore, careful evaluation of compensatory curves as well as of the main curve is important to prevent the development of PJK in the treatment of AIS.

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Continuous lengthening potential after four years of magnetically controlled spinal deformity correction in children with spinal muscular atrophy

Scientific Reports ◽

10.1038/s41598-020-79821-x ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Heiko M. Lorenz ◽

Marina M. Hecker ◽

Lena Braunschweig ◽

Batoul Badwan ◽

Konstantinos Tsaknakis ◽

...

Keyword(s):

Spinal Muscular Atrophy ◽

Spinal Deformity ◽

Muscular Atrophy ◽

Deformity Correction ◽

Pelvic Obliquity ◽

Complication Rates ◽

Scoliotic Curve ◽

Level Of Evidence ◽

Growing Rods

AbstractMagnetically controlled growing rods (MCGR) are commonly implanted for the treatment of early-onset scoliosis. While most authors report favorable short-term results, little is known about long-term deformity correction. This prospective cohort study assesses spinal deformity control in a homogeneous spinal muscular atrophy (SMA) patient group treated with MCGR implants, a standardized lengthening protocol and a minimum follow-up of four years. 17 SMA patients with progressive scoliosis were treated with MCGR implanted parallel to the spine with rib-to-pelvis fixation. Radiologic measurements were performed before and after MCGR implantation and during external lengthening procedures. These included measurements of the scoliotic curve, kyphosis, lordosis, pelvic obliquity and the spinal length. Additional clinical data of the complications were also analyzed. 17 children (mean age 7.4 years) were surgically treated and underwent a total of 376 lengthenings. Complication rates were 3.5% in respect to all interventions or 41% of the patients had complications during 3.5% of the lengthening sessions. The initial implantation significantly reduced the main scoliotic curve by 59%, with the correction remaining constant throughout the follow-up. Pelvic obliquity was also significantly and permanently corrected by 72%, whereas kyphosis and lordosis were not influenced. The spinal length could be significantly increased mostly during the first year of treatment. Bilateral implantation of MCGRs for correction of spinal deformity in children with SMA showed no decrease of the lengthening potential during a four-year follow-up. Therefore, the previously described ‘law of diminishing returns’ could not be applied to this patient population.Level of Evidence/Clinical relevance: Therapeutic Level IV.

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Concave or convex rod translation first in adolescent idiopathic scoliosis instrumentation with differential rod contouring?

Studies in Health Technology and Informatics - Research into Spinal Deformities 9 ◽

10.3233/shti210455 ◽

2021 ◽

Author(s):

X Wang ◽

CE Aubin ◽

RM Schwend

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Cobb Angle ◽

Thoracic Kyphosis ◽

Deformity Correction ◽

Vertebral Rotation ◽

Convex Side ◽

Bone Screw ◽

Apical Vertebral Rotation ◽

Clinically Significant

The objective was to assess deformity correction and bone-screw force associated respectively with concave manipulation first, convex manipulation first, and different differential rod contouring configurations. Instrumentation scenarios were computationally simulated for 10 AIS cases with mean thoracic Cobb angle (MT) of 54±8°, apical vertebral rotation (AVR) of 19±2° and thoracic kyphosis of 21±9°. Instrumentations with major correction maneuvers using the concave side rod were first simulated; instrumentations with major correction maneuvers using the convex side rod were then simulated. Simulated correction maneuvers were concave/convex rod translation followed by apical vertebral derotation and then convex/concave rod translation. There were no significant differences in deformity corrections and bone-screw forces between concave rod translation first and convex rod translation first with differential rod contouring. Increasing differential rod contouring angle and concave rod diameter improved AVR correction and increased the TK and bone-screw forces; the effect on the MT Cobb angle was not clinically significant.

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P.351Gene-replacement therapy (GRT) in spinal muscular atrophy type 1 (SMA1): long-term follow-up from the onasemnogene abeparvovec phase 1/2a clinical trial

Neuromuscular Disorders ◽

10.1016/j.nmd.2019.06.513 ◽

2019 ◽

Vol 29 ◽

pp. S184

Author(s):

J. Mendell ◽

R. Shell ◽

K. Lehman ◽

M. McColly ◽

L. Lowes ◽

...

Keyword(s):

Clinical Trial ◽

Spinal Muscular Atrophy ◽

Replacement Therapy ◽

Muscular Atrophy ◽

Phase 1 ◽

Spinal Muscular Atrophy Type ◽

Long Term Follow Up

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Comparative analysis of pedicle screw versus hybrid instrumentation in adolescent idiopathic scoliosis surgery

Journal of Neurosciences in Rural Practice ◽

10.4103/0976-3147.185510 ◽

2016 ◽

Vol 7 (04) ◽

pp. 550-553 ◽

Cited By ~ 4

Author(s):

Sohail Rafi ◽

Naseem Munshi ◽

Asad Abbas ◽

Rabia Hassan Shaikh ◽

Imtiaz Hashmi

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Cobb Angle ◽

Pedicle Screw ◽

Pedicle Screws ◽

Scoliosis Surgery ◽

Hybrid Instrumentation ◽

System Versus ◽

Cobb’S Angle

ABSTRACT Introduction: Adolescent idiopathic scoliosis is the most common type of scoliosis. A Cobb angle of 50° will progress beyond the age of spinal maturity. Surgery over bracing is advised at a Cobb angle above or equal to 50°. The aim of surgery is to bring the Cobb angle down below 50° to prevent reprogression as well as improve the quality of life. The objective of the study is to analyze the efficacy and significance in lifestyle improvement of pedicle screw-only fixation system versus the more common hybrid instrumentation system used for the surgical treatment of adolescent idiopathic scoliosis. Materials and Methods: A prospective cohort study was conducted involving two groups of patients were included in the study. One group was operated with pedicle screw-only method while the other with hybrid instrumentation system. The pre- and post-operative Cobb’s angles were taken across a follow-up of 4 years. An SRS-30 questionnaire was given in a yearly follow-up to assess the lifestyle improvement of the patient. Results: Pedicle screw-only method was significantly more effective in reducing Cobb’s angle (P = 0.0487). It was showed less loss of correction (P = 0.009) pedicle screw-only surgery was also better at reducing thoracic curves (P = 0.001). There seemed a better recovery time with pedicle screw surgery (P = 0.003). Conclusion: Pedicle screws are more effective and durable than hybrid systems at when treating adolescent idiopathic scoliosis.

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