Showing papers by "Behrooz A. Akbarnia published in 2020"

Idiopathic Early-Onset Scoliosis: Growing Rods Versus Vertically Expandable Prosthetic Titanium Ribs at 5-Year Follow-up.

Abstract: BACKGROUND Distraction-based techniques allow spinal growth until skeletal maturity while preventing curve progression. METHODS Two multicenter early-onset scoliosis databases were used to identify patients with idiopathic spine abnormalities treated with traditional growing rods (TGR) or vertically expandable titanium ribs (VEPTR). Patients underwent at least 4 lengthenings and had at least 5-year follow-up. Significance was set at P<0.05. RESULTS In total, 50 patients treated with TGR and 22 treated with VEPTR were included. Mean (±SD) age at surgery was 5.5 (±2.0) years for the TGR group versus 4.3 (±1.9) years for the VEPTR group (P=0.044); other demographic parameters were similar. VEPTR patients had more procedures (mean 15±4.2) than TGR patients (mean 10±4.0) (P=0.001). Unilateral constructs were present in 18% (4 of 22) of VEPTR and 16% (8 of 50) of TGR patients. Bilateral constructs spanned a mean 2.1 additional surgical levels and exposed patients to 1.6 fewer procedures than unilateral constructs. Curve correction was similar between bilateral and unilateral constructs. TGR patients experienced greater curve correction (50%) than VEPTR patients (27%) (P<0.001) and achieved a greater percentage of thoracic height gain (24%) than VEPTR patients (12%) (P=0.024). At latest follow-up, TGR patients had better maintenance of curve correction, less kyphosis, and 15% greater absolute gain in thoracic height versus VEPTR patients. TGR patients had a lower rate of wound complications (14%) than VEPTR patients (41%) (P=0.011). CONCLUSIONS In patients with idiopathic early-onset scoliosis, TGRs produced greater initial curve correction, greater thoracic height gains, less kyphosis, and lower incidence of wound complications compared with VEPTR. LEVEL OF EVIDENCE Level III.

Characterizing Use of Growth-friendly Implants for Early-onset Scoliosis: A 10-Year Update.

Abstract: BACKGROUND Growth-friendly treatment of early-onset scoliosis (EOS) has changed with the development and evolution of multiple devices. This study was designed to characterize changes in the use of growth-friendly implants for EOS from 2007 to 2017. METHODS We queried the Pediatric Spine Study Group database for patients who underwent index surgery with growth-friendly implants from July 2007 to June 2017. In 1298 patients, we assessed causes of EOS; preoperative curve magnitude; age at first surgery; patient sex; construct type; lengthening interval; incidence of "final" fusion for definitive treatment; and age at definitive treatment. α=0.05. RESULTS From 2007 to 2017, the annual proportion of patients with idiopathic EOS increased from 12% to 33% (R=0.58, P=0.006). Neuromuscular EOS was the most common type at all time points (range, 33% to 44%). By year, mean preoperative curve magnitude ranged from 67 to 77 degrees, with no significant temporal changes. Mean (±SD) age at first surgery increased from 6.1±2.9 years in 2007 to 7.8±2.5 years in 2017 (R=0.78, P<0.001). As a proportion of new implants, magnetically controlled growing rods increased from <5% during the first 2 years to 83% in the last 2 years of the study. Vertically expandable prosthetic titanium ribs decreased from a peak of 48% to 6%; growth-guidance devices decreased from 10% to 3%. No change was seen in mean surgical lengthening intervals (range, 6 to 9 mo) for the 614 patients with recorded lengthenings. Final fusion was performed in 88% of patients who had undergone definitive treatment, occurring at a mean age of 13.4±2.4 years. CONCLUSIONS From 2007 to 2017, neuromuscular EOS was the most common diagnosis for patients treated with growth-friendly implants. Patient age at first surgery and the use of magnetically controlled growing rods increased during this time. Preoperative curve magnitude, traditional growing rod lengthening intervals, and rates of final fusion did not change. LEVEL OF EVIDENCE Level II.

MRI utilization and rates of abnormal pretreatment MRI findings in early-onset scoliosis: review of a global cohort.

Abstract: Retrospective review To report the frequency of pretreatment magnetic resonance imaging (MRI) utilization and rates and types of intra-spinal abnormalities identified on MRI in patients with early-onset scoliosis (EOS). MRI can help identify spinal cord abnormalities in patients with EOS. We reviewed data from patients enrolled from 1993–2018 in an international EOS registry. Patients with incomplete/unverifiable data and those with spinal deformities secondary to infection or tumor were excluded, leaving 1343 patients for analysis. Demographic characteristics, pretreatment major curve magnitude, treatment type, and MRI findings were analyzed. Patients were categorized by EOS type (congenital, idiopathic, neuromuscular, syndromic), pretreatment MRI utilization, and presence of intra-spinal abnormality on MRI. Univariate testing and multivariate logistic regression were performed to identify demographic, radiographic, and clinical predictors of MRI utilization and abnormal MRI findings. MRI was used in 836 patients (62%). Pretreatment MRI utilization rates ranged from 42% in neuromuscular EOS to 74% in congenital EOS. Prevalence of abnormal MRI findings was 24% overall, ranging from 13% in patients with idiopathic EOS to 39% in neuromuscular EOS. Compared with white/Caucasian patients, Asian/Asian-American patients had higher odds of MRI utilization and abnormal MRI findings. Treatment type, pretreatment major curve magnitude, age at MRI, and age at treatment were not associated with abnormal MRI findings. Overall, 249 abnormalities were identified in 197 patients. The most common findings were syrinx and tethered cord. Syrinx with Chiari malformation was the most frequent combination of abnormal findings. In the two-thirds of patients who underwent MRI before EOS treatment, findings were abnormal in 24%. EOS type and race/ethnicity were associated with both MRI utilization and abnormal findings. The most frequent abnormalities were syrinx and tethered cord, and the type of abnormalities appeared to differ by EOS type. Prognostic, Level III.

Minimum 5-Year Follow-up on Graduates of Growing Spine Surgery for Early Onset Scoliosis.

Abstract: Introduction After discontinuation of growth friendly (GF) surgery for early onset scoliosis, patients undergo spinal fusion or continued observation. This last planned treatment is colloquially called "definitive" treatment, conferring these patients as "graduates" of a growing program. The 5-year radiographic and clinical outcomes of this cohort are unknown. Methods An international pediatric spine database was queried for patients from a GF program (spine or rib-based) with minimum 5-year follow-up from last planned surgery (GF or spinal fusion). Radiographs and charts were reviewed for main coronal curve angle and maximum kyphosis as well as occurrence of secondary surgery. Results Of 580 graduates, 170 (29%) had minimum 5-year follow-up (37% male). Scoliosis etiology was congenital in 41 (24%), idiopathic 36 (21%), neuromuscular 51 (30%), and syndromic 42 (25%). Index surgery consisted of spine-based growing rods in 122 (71%) and rib-based distraction in 48 (29%). Mean age at index surgery was 6.8 years, and patients underwent an average of 5.4 lengthenings over an average of 4.9 years (range, 6 mo to 11 y). Last planned treatment was at an average age of 11.8 years (range, 7 to 17 years). Last planned treatment consisted of spinal fusion in 114 patients, 47 had growing implants maintained, 9 had implants removed. Average follow-up was 7.3 years (range, 5 to 13 y).When compared from postdefinitive treatment to 2-year follow-up, there was noted progression of the coronal curve angle (46±19 to 51±21 degrees, P=0.046) and kyphosis (48±20 to 57±25 degrees, P=0.03). However, between 2 and 5 years, no further progression occurred in the coronal (51±21 to 53±21 degrees, P=0.26) or sagittal (57±25 to 54±28 degrees, P=0.93) planes. When stratified based on etiology, there was no significant coronal curve progression between 2- and 5-year follow-up. When comparing spinal fusion patients to those who had maintenance of their growing construct, there was also no significant curve progression.Thirty-seven (21%) underwent at least 1 (average, 1.7; range, 1 to 7) revision surgery following graduation, and 15 of 37 (41%) underwent 2 or more revision surgeries. Reason for revision was implant revision (either GF or spinal fusion) in 34 patients, and implant removal in 3. On an average, the first revision was 2.5 years after the definitive treatment plan (range, 0.02 to 7.4 y). In total, 15 of 37 (41%) revisions occurred over 2 years following the final decision for treatment plan, and 7 of 37 (19%) occurred 5 or more years after the definitive treatment.Patients who underwent spinal fusion as a definitive treatment strategy were more likely to undergo revision surgery (27%) than patients who had their GF implants maintained (11%) (P=0.04). Conclusions Five years following "graduation" from growing surgery for early onset scoliosis, there is progression of curve magnitude in both the coronal and sagittal planes up to 2 years, with no further progression at 5 years. A total of 21% of patients undergo at least 1 revision surgery, and average time to revision surgery is over 2 years from last planned surgery. Risk of revision surgery was higher in patients who underwent a spinal fusion as their definitive treatment strategy. Level evidence Level III-retrospective comparative. Type of evidence Therapeutic.

Growth-preserving instrumentation in early-onset scoliosis patients with multi-level congenital anomalies

Abstract: Retrospective. To assess final outcomes in patients with early-onset scoliosis (EOS) who underwent growth-preserving instrumentation (GPI). Various types of growth-preserving instrumentation (GPI) are frequently employed, but until recently had not been utilized long enough to assess final outcomes. GPI “graduates” with multi-level congenital curves were identified. Graduation was defined as a final fusion or 5 years of follow-up without planned future surgeries. Outcomes included radiographic parameters and complications. 26 patients were included. 11 had associated diagnoses; eight had fused ribs. 17 were treated with traditional growing rods, seven with vertically expandable prosthetic ribs, and two with Shilla procedures. The mean GPI spanned 12.3 levels including 10.7 motion segments, age at index surgery was 5.5 years, treatment spanned 7.5 years, and follow-up was 9.2 years. 24 patients underwent final fusion. Mean major curve decreased from 73° to 49° with index surgery (p 60° in 6 patients (23%). None worsened throughout treatment. Mean T1–T12 height increased 2.4 cm with index surgery (p = 0.02) and 5.4 cm total (p 22 cm in 6 patients (23%). On average, there were 2.6 complications per patient, including 1.7 implant failures. 12 patients (46%) experienced ≥ 3 complications; four patients (15%) experienced none. We observed successful prevention of deformity progression but substantial residual deformity among GPI graduates with multi-level congenital EOS. Most coronal curve correction was attained during GPI implantation; thoracic height improved throughout treatment. While some favorable results were found, treatment strategies allowing improved deformity correction would be valuable for this challenging population. Therapeutic-III.

Anterior Column Realignment: Analysis of Neurological Risk and Radiographic Outcomes

Abstract: BACKGROUND Anterior column realignment (ACR) is a less invasive alternative to 3-column osteotomy for the correction of sagittal imbalance. We hypothesized that ACR would correct sagittal imbalance with an acceptable neurological risk. OBJECTIVE To assess long-term neurological and radiographic outcomes after ACR. METHODS Patients ≥18 yr who underwent ACR from 2005 to 2013 were eligible. Standing scoliosis radiographs were studied at preoperation, postoperation (≤6 wk), and at minimum 2 yr of follow-up. Clinical/radiographic data were collected through a retrospective chart review, with thoracic 1 spino-pelvic inclination (T1SPi) used as the angular surrogate for sagittal vertical axis. RESULTS A total of 26 patients had complete data, with a mean follow-up of 2.8 yr (1.8-7.4). Preoperative, sagittal parameters were lumbar lordosis (LL) of -16.1°, pelvic incidence (PI)-LL of 41.7°, T1SPi of 3.6°, and pelvis tilt (PT) of 32.4°. LL improved by 30.6° (P < .001) postoperation. Mean changes in PT (-8.3), sacral slope (8.9), T1SPi (-4.9), and PI-LL (-33.5) were all significant. The motion segment angle improved by 26.6°, from 5.2° to -21.4° (P < .001). Neurological complications occurred in 32% patients postoperation (n = 8; 1 patient with both sensory and motor). New thigh numbness/paresthesia developed in 3 (13%) patients postoperation; only 1 (4%) persisted at latest follow-up. A total of 6 (24%) patients developed a new lower extremity motor deficit postoperation, with 4 (8%) having persistent new weakness at last follow-up. Out of 8 patients with preoperative motor deficit, half saw improvement postoperation and 75% improved by last follow-up. CONCLUSION There was net motor improvement, with 24% of patients improving and 16% having persistent new weakness at latest follow-up; 60% were unchanged. Radiographic results demonstrate that ACR is a useful tool to treat severe sagittal plane deformity.

An initial effort to define an early onset scoliosis "graduate"-The Pediatric Spine Study Group experience.

Abstract: Increasingly, patients with early onset scoliosis (EOS) are completing a growth friendly surgical program followed by observation, removal of implants or a definitive spinal fusion. These patients are colloquially referred to as “graduates”. A standardized definition of a graduate is needed for research and comparing the outcomes, family counseling, and a better understanding of the population. A 15-question electronic survey was completed by 39 experienced pediatric spine surgeons to identify factors salient to the definition of a graduate of EOS surgical programs. A Delphi/Nominal group technique session with nine questions was then performed face-to-face with 21 members of the Pediatric Spine Study Group to discuss and refine the definition. A follow-up electronic survey was then distributed to these same 21 members to gain consensus on the final definition. From the initial survey, it was identified that a graduate did not require definitive spinal fusion after a growing program. From the Delphi session, it was determined that skeletal maturity was the most important factor in defining a graduate. A strictly defined minimum length of follow-up was not felt to be a prerequisite for qualification of graduation. After the final electronic version was distributed, > 80% of respondents agreed upon the final definition, thereby achieving consensus. The Pediatric Spine Study Group recommends adoption of the following definition: a “graduate” is a patient who has undergone any surgical program to treat early onset scoliosis, and has reached skeletal maturity and does not have a planned surgical intervention for EOS in the future. V.