Predicting Immediate Lordosis Restoration After Anterior Lumbar Interbody Fusion and the Effect of Posterior Column Osteotomies.

OBJECTIVE: Anterior lumbar interbody fusion (ALIF) can be combined with posterior column osteotomies (PCOs) to maximize lordotic correction. This study compares radiographic changes in regional and segmental lordosis in patients undergoing ALIF with and without PCOs. METHODS: Patients >18 years old who underwent ALIF at 1 or 2 segments at a single institution (January 2014-July 2020) were included. Preoperative and postoperative radiographic parameters were determined, and a propensity-matched analysis was performed. RESULTS: Ninety-nine patients (53 [54%] men) underwent ALIF at 129 levels (mean [SD], 1.3 [0.46] levels; median [range] age, 61 [32-83] years). PCOs were performed in 13 (13%) patients at 19 (15%) segments. PCOs included 13 Schwab grade 1 and 6 grade 2 osteotomies. All measures, including lumbar lordosis, segmental lordosis, disc angle, and neural foramen height, increased significantly after surgery (P ≤ 0.003). In the propensity-matched analysis, PCO was associated with greater increases in lumbar lordosis (14.9° vs. 8.2°, P = 0.02), segmental lordosis (14.0° vs. 9.6°, P = 0.03), and disc angle (15.0° vs. 10.2°, P = 0.046). The change in disc angle more closely approximated the inherent lordosis of the cage when PCO was performed (94% vs. 62%, P = 0.004). CONCLUSIONS: Performing PCOs and ALIFs significantly increased the radiographic correction of overall and segmental lordosis in the selected patient cohort. The disc angle achieved with ALIF without PCOs was approximately 60% of the cage lordosis. The addition of PCO allowed for greater segmental compression, enabling the disc angle to reach nearly 100% of the inherent interbody cage lordosis.

Enlarged posterior column osteotomy plus intervertebral cage strutting for lumbosacral nerve bowstring disease.

BACKGROUND: To explore the surgical outcome of enlarged posterior column osteotomy (EPCO) plus intervertebral cage strutting (ICS) for patients with lumbosacral nerve bowstring disease (BSD). METHODS: The clinical data of 27 patients with BSD that surgically treated with EPCO plus ICS from January 2018 to March 2021 were retrospectively reviewed. Patient demographics including age, gender, body mass index (BMI), duration, length of hospital stay, SF-36 were recorded. Surgical data including operation time, blood loss, surgical level, and complications were recorded. Inter-pedicle distance and regional lumbar lordosis was measured at lateral X-ray at both pre- and postoperative. RESULTS: All patients underwent the operation successfully. EPCO plus ICS was performed at L4-L5 in 9 patients, at L5-S1 in 7 patients, at L4-S1 in 6 patients, at L3-L5 in 5 patients. The mean operation time was 96.3 ± 18.0 min, mean blood loss was 350.0 ± 97.9 mL. Relaxation of thecal sac was noticed after pedicle screw-rod compression bilaterally. The mean decrease of inter-pedicle distance was 0.57 ± 0.18 cm, the mean increase of regional lumbar lordosis was 17.6 ± 6.7 degrees. Relaxation of cauda equina within the thecal sac was noticed at intra-operative after pedicle screw-rod compression bilaterally in all the patients. Most patients achieved neurological function improvement at two-year follow up. CONCLUSIONS: EPCO plus ICS procedure is an effective surgical method for lumbosacral nerve BSD through restoring the coordination between column and cord, visual relaxation of cauda equina within the thecal sac at intraoperative is the key factor in determining the relief of neurological function at postoperative.

The Comparison of Posterior Intervertebral Release Combined with Posterior Column Osteotomy and Posterior Column Osteotomy Alone for the Treatment of Moderate-to-Severe Rigid Scoliosis: A Prospective Controlled Study.

OBJECTIVES: There is no consensus on the treatment of moderate-to-severe rigid scoliosis. Anterior release and three-column osteotomy are excessively traumatic, whereas posterior column osteotomy (PCO) alone results in poor outcomes. An emerging surgical technique, posterior intervertebral release (PR), can release the rigid spine from the posterior approach. This study was performed to compare the multi-segment apical convex PR combined with PCO and PCO alone in patients with moderate-to-severe rigid scoliosis. METHODS: From June 2021 to June 2022, this prospective study of moderate-to-severe (Cobb: 70-90°) rigid scoliosis (flexibility of main curve <25%) involved two groups defined by surgical procedure: the PR group, the patients undergoing PR combined with PCO; and the PCO group, the patients undergoing PCO alone. Follow-up was at least 12 months. Radiographic results mainly included main curve Cobb, correction of per PR/PCO segment, apical vertebra rotation (AVR) and apical vertebra translation (AVT). Demographics, surgical data, complications were also recorded. Student's independent samples t test and Pearson's chi-square test were used to compare the differences between groups. RESULTS: Forty patients with an average age of 16.65 years were included (PR group, n = 20; PCO group, n = 20). The main curves averaged 77.56° ± 5.86° versus 78.02° ± 5.72° preoperatively and 20.07° ± 6.73° versus 33.58° ± 5.76° (p < 0.001) at the last follow-up in the PR and PCO groups, respectively. The mean correction rates were 74.30% and 56.84%, respectively (p < 0.001). The average coronal curve correction was 13.49° per release segment, which was significantly higher than the PCO correction of 6.20° (p < 0.001). The correction of apical vertebra rotation and translation in the main thoracic curve was significantly better in the PR group than in the PCO group (p < 0.05). Several minor complications in the two groups improved after conservative treatment. CONCLUSION: The multi-segment apical convex PR combined with PCO offers more advantages than PCO alone in the treatment of patients with moderate-to-severe rigid scoliosis. Owing to its excellent corrective effect and few complications, this is a high benefit-risk ratio surgical strategy for rigid scoliosis.

A comparison of three- and two-rod constructs in the correction of severe pediatric scoliosis.

Purpose: Managing severe scoliosis is challenging and risky with a significant complication rate regardless of treatment strategy. In this retrospective comparative study, we report our results using a three-rod compared to two-rod construct in the surgical treatment of severe spine deformities to investigate which technique is safer, and which provides superior radiological outcomes. Methods: Forty-six consecutive patients undergoing posterior spine fusion for scoliosis between 2006 and 2017 were identified in our institutional records. Inclusion criteria were minimum coronal deformity of 90°, age < 18 years at the time of surgery and a minimum 2 years of follow-up. Radiographic and clinical parameters, as well as post-operative complications were compared between the two groups. Results: There were 21 patients in the three-rod group and 25 in the two-rod group. The mean preoperative major coronal deformity was 100°± 9 and 102°± 10 in the three-rod and two-rod, respectively (p = 0.6). The average major curve correction was 51% and 59% in three-rod and two-rod groups, respectively (p = 0.03). The post-operative thoracic kyphosis was 30°± 11 and 21°± 12 in the three-rod and the two-rod groups, respectively (p = 0.01). The surgical time was 476 ± 52 and 387 ± 84 min in three-rod and two-rod, respectively (p < 0.01). One patient in the two-rod cohort showed permanent post-operative sensory deficit. There were three unplanned returns to operating theater in the two-rod group. Conclusions: Coronal correction was better with two-rod, whereas sagittal balance was superior with three-rod. Both techniques achieved balanced spine treating severe scoliosis. The two-rod technique was associated with a higher likelihood of requiring revision surgery. Level of evidence: level 3.

Surgical correction of a previously operated juvenile idiopathic scoliosis with crankshaft phenomenon: an illustrative case report.

Background: Crankshaft phenomenon secondary to posterior fusion for scoliotic deformity at a young age has become rare and its management can be very challenging. Case Description: We report the case of an 11-year-old girl who has been complaining of a progressively increasing hump in her back with waist and shoulders asymmetry during the past 6 months. Three years prior to presentation, she underwent in another institution posterior correction fusion from T3 to L3 for a juvenile idiopathic scoliosis with a Cobb angle of 60°. After the initial correction, follow-up X-rays revealed a progressive increase of the scoliosis angulation with the onset of a coronal malalignment mainly at the cervicothoracic junction. Full spine anteroposterior and lateral X-rays revealed a long right thoracolumbar scoliosis of 70° with a rib-vertebra angle difference of 27° and the proximal right screw pulled out from the rod. CT scan confirmed the posterior fusion between the apical vertebras. MRI did not show any congenital anomaly. The patient underwent a revision surgery with instrumentation from T1 to L4, and posterior column osteotomies at 6 levels between T4 and T10. Coronal Cobb angle corrected to 11° with satisfactory sagittal alignment and a maintained correction at 3 years of follow-up. Conclusions: This is the first case to thoroughly illustrate surgical management in the onset of a crankshaft phenomenon. Through a posterior-only approach, the use of posterior column osteotomies at the apex of the deformity in order to release the previous fusion is a safe and satisfactory option to reestablish proper coronal and sagittal alignment, with satisfactory clinical and radiological long-term results.

Anterior longitudinal ligament release from a posterior approach: an alternative to three-column osteotomy.

PURPOSE: Expansion of the anterior column and compression of the posterior column restores lordosis and sagittal imbalance. Anterior longitudinal ligament (ALL) release has been described from lateral and anterior approaches as a technique to improve lumbar lordosis; however, posterior approach to release the ALL has not been adequately assessed. METHODS: We demonstrate a case series of ALL release using a posterior approach performed in conjunction with posterior column osteotomy (PCO), with or without transforaminal lumbar interbody fusion (TLIF) for spinal deformity. Eleven cases were identified from billing records between 2010 and 2019. Retrospective review was conducted for perioperative complications and revision surgery. Overall and segmental lumbar lordosis (LL) correction was measured from pre- and postoperative imaging. RESULTS: Eleven patients underwent ALL release with a PCO. Kyphosis, scoliosis, and flat back syndrome were the most common spinal deformities. On average, patients had 9 ± 3 levels fused and a single level ALL release. ALL release was most commonly performed at L1-L2 and L2-L3 levels. An overall LL correction of 28.6° ± 19.8o was achieved; ALL release introduced 16.7° ± 11.9° of lordotic correction and accounted for 49.2 ± 30.4% of the overall lordotic correction. Average blood loss was 1030 ± 573 mL. CONCLUSIONS: ALL release as an adjunct to PCO and TLIF is a viable technique for providing increased deformity correction without subjecting the patient to a more invasive three-column osteotomy. While this approach may not be appropriate for all patients, it represents a useful option in spinal deformity correction while limiting blood loss and additional anterior surgery. LEVEL OF EVIDENCE: IV.

One-stage multiple posterior column osteotomies and fusion and pre-op halo-gravity traction may result in a comparative and safer correction of complex spine deformity than vertebral column resection.

STUDY DESIGN: A retrospective review of prospectively collected from patients recruited at a single center. PURPOSE: To test whether safe and optimal correction can be obtained with preoperative halo-gravity traction and posterior spinal fusion with adjunctive procedures but without VCR. Posterior vertebral column resection(VCR) is gaining popularity for correction of severe spinal deformity. However, it is a highly technically demanding procedure with potential risk for complications and neurological injury. METHODS: In total, 72 patients with severe spinal deformity (Cobb angle > 100º) who underwent HGT followed by definitive PSF with PCO, with or without concave rib osteotomy and thoracoplasty. Demographic and surgical data were collected. Conventional coronal and sagittal radiographic measurements were obtained pre-traction, post-traction, post-op and at follow-up to determine the final deformity correction. Postoperative neurological and major complications were reviewed. We used Chi-square to compare proportion between groups and t test to compare groups in quantitative/ordinal variables. RESULTS: There were 72 patients (35 females, 37 males). The etiology was congenital (21),idiopathic (45), neurofibromatosis (2) and neuromuscular (4). The mean was: age 18 ± 4.6 years; duration of HGT 103 ± 35 days; coronal Cobb angle before traction 131.5 ± 21.4º vs 92. ± 15.9º after HGT (30% correction) and 72.8 ± 12.7º after fusion (47% correction); kyphosis angle before traction 134.7 ± 32.3º vs 97.1 ± 22.4º after HGT and 73.7 ± 21.3º post-fusion. Number of fusion levels 14 ± 1; EBL 1730 ± 744 cc; number of PCOs done 5 ± 2; number of concave rib osteotomies (2 ± 2). There were 16 patients with postoperative complications (22.2%), 10 medical, one wound infection, 2 implant related and 3 post-op neuro-deficits (all of whom recovered at follow-up). There was one death (cardiac arrest). CONCLUSION: HGT and one-stage posterior fusion with PCO, with or without concave rib resection and thoracoplasty, without VCR, achieved satisfactory correction of rigid complex spine deformity with minimal neurological complications. The results compare favorably with previous reports of similar deformities treated with VCR. LEVEL OF EVIDENCE: III.

Posterior column osteotomy plus unilateral cage strutting for correction of lumbosacral fractional curve in degenerative lumbar scoliosis.

BACKGROUND: Inadequate release of the posterior spinal bone elements may hinder the correction of the lumbosacral fractional curve in degenerative lumbar scoliosis, since the lumbosacral junction tends to be particularly rigid and may already be fused into an abnormal position. The purpose of this study was to evaluate the surgical outcome and complications of posterior column osteotomy plus unilateral cage strutting technique on lumbosacral concavity for correction of fractional curve in degenerative lumbar scoliosis patients. METHODS: Thirty-two degenerative lumbar scoliosis patients with lumbosacral fractional curve more than 15° that were surgically treated by posterior column osteotomy plus unilateral cage strutting technique were retrospectively reviewed. The patients' medical records were reviewed to identify demographic and surgical data, including age, sex, body mass index, back pain, leg pain, Oswestry Disability Index, operation time, blood loss, and instrumentation levels. Radiological data including coronal balance distance, Cobb angle, lumbosacral coronal angle, sagittal vertical axis, lumbar lordosis, and lumbosacral lordotic angle were evaluated before and after surgery. Cage subsidence and bone fusion were evaluated at 2-year follow-up. RESULTS: All patients underwent the operation successfully; lumbosacral coronal angle changed from preoperative 20.1 ± 5.3° to postoperative 5.8 ± 5.7°, with mean correction of 14.3 ± 4.4°, and the correction was maintained at 2-year follow-up. Cobb's angle and coronal balance distance decreased from preoperative to postoperative; the correction was maintained at 2-year follow-up. Sagittal vertical axis decreased, and lumbar lordosis increased from preoperative to postoperative; the correction was also maintained at 2-year follow-up. Lumbosacral lordotic angle presented no change from preoperative to postoperative and from postoperative to 2-year follow-up. Postoperatively, there were 8 patients with lumbosacral coronal angle more than 10°, they got the similar lumbosacral coronal angle correction, but presented larger preoperative Cobb and lumbosacral coronal angle than the other 24 patients. No cage subsidence was detected; all patients achieved intervertebral bone fusion and inter-transverse bone graft fusion at the lumbosacral region at 2-year follow-up. CONCLUSION: Posterior column osteotomy plus unilateral cage strutting technique on the lumbosacral concavity facilitate effective correction of the fractional curve in degenerative lumbar scoliosis patients through complete release of dural sac as well as the asymmetrical intervertebral reconstruction by cage.

Surgical Outcomes of Multilevel Posterior Lumbar Interbody Fusion versus Lateral Lumbar Interbody Fusion for the Correction of Adult Spinal Deformity: A Comparative Clinical Study.

STUDY DESIGN: A retrospective case control study. PURPOSE: The purpose of this study was to compare the surgical outcomes of multilevel lateral lumbar interbody fusion (LIF) and multilevel posterior lumbar interbody fusion (PLIF) in the surgical treatment of adult spinal deformity (ASD) and to evaluate the sagittal plane correction by combining LIF with posterior-column osteotomy (PCO). OVERVIEW OF LITERATURE: The surgical outcomes between multilevel LIF and multilevel PLIF in ASD patients remain unclear. METHODS: We retrospectively reviewed 31 ASD patients who underwent multilevel LIF combined with PCO (LIF group, n=14) or multilevel PLIF (PLIF group, n=17) and with a minimum 2-year follow-up. In the comparison between LIF and PLIF groups, their mean age at surgery was 69.4 vs. 61.8 years while the mean follow-up period was 29.2 vs. 59.3 months. We evaluated the transition of pelvic incidence-lumbar lordosis (PI-LL) and disc angle (DA) in the LIF group, in fulcrum backward bending (FBB), after LIF and after posterior spinal fusion (PSF) with PCO. The spinopelvic radiographic parameters were compared between LIF and PLIF groups. RESULTS: Compared with the PLIF group, the LIF group had less blood loss and comparable surgical outcomes with respect to radiographic data, health-related quality of life scores and surgical time. In the LIF group, the mean DA and PI-LL were unchanged after LIF (DA, 5.8°; PI-LL, 15°) compared with the values using FBB (DA, 4.3°; PI-LL, 15°) and improved significantly after PSF with PCO (DA, 8.1°; PI-LL, 0°). CONCLUSIONS: In the surgical treatment of ASD, multilevel LIF is less invasive than multilevel PLIF and combination of LIF and PCO would be necessary for optimal sagittal correction in patients with rigid deformity.

Multilevel extended posterior column osteotomy plus unilateral cage strutting for degenerative lumbar kyphoscoliosis.

OBJECTIVE: To explore the surgical outcome of patients with degenerative lumbar kyphoscoliosis who underwent multilevel extended posterior column osteotomy (PCO) plus unilateral cage strutting (UCS). METHODS: From Jan 2012 to Aug 2017, 23 patients with degenerative lumbar kyphoscoliosis who underwent multilevel extended PCO plus UCS technique (study group) and 13 patients who underwent asymmetrical pedicle subtraction osteotomy (PSO) technique (control group) were retrospectively reviewed; the radiological features, including coronal/sagittal deformity, and clinical evaluation including Oswestry Disability Index (ODI), visual analog scale (VAS), and Japanese Orthopedic Association (JOA) scores-lumbar were assessed before surgery and at follow-up. RESULTS: All patients underwent the operation successfully. There was no difference in fusion level, blood loss, and follow-up duration between the two groups; the operation time and length of hospital stay were shorter in study group than that in control group. All patients achieved significant correction of both scoliotic and kyphotic deformity and maintained the correction at minimum of two year follow-up, without any difference in deformity correction and correction loss between the two groups. All patients got back pain and leg pain alleviation and neurological function improvement at two year follow-up, without any difference between the two groups. The incidence of complications was lower in study group than that in control group. CONCLUSION: Multilevel extended PCO plus UCS procedure could achieve significant correction of scoliosis and kyphosis in the treatment of degenerative lumbar kyphoscoliosis, presenting less surgery time, lower incidence of complication, and shorter hospital stay when compared with the asymmetric PSO technique.

Minimally invasive multilevel lateral lumbar interbody fusion with posterior column osteotomy compared with pedicle subtraction osteotomy for adult spinal deformity.

BACKGROUND CONTEXT: Pedicle subtraction osteotomy (PSO) is highly effective as a sagittal correction approach in patients with adult spinal deformity, but relevant issues such as surgical complexity and long-term complications limit its applicability. Recently, minimally invasive techniques have been reported to be useful for surgical treatment of adult spinal deformity; however, few reports have directly compared these techniques with PSO. PURPOSE: The purpose of this study was to evaluate the radiological and clinical efficacies of oblique lateral interbody fusion (OLIF) with posterior column osteotomy (PCO) using stiff rods (6.35-mm cobalt chrome [CoCr]). STUDY DESIGN: Retrospective comparative study. PATIENT SAMPLE: One-hundred six patients (average age 71.3 years) diagnosed with adult spinal deformity presenting with sagittal imbalance for whom follow-up of over 2 years after sagittal correction (between 2013 and 2017) was available. OUTCOME MEASURES: Description and analysis of X-ray, computed tomography scans, operative time, estimated blood loss, and clinical outcomes (Oswestry Disability Index [ODI] and Visual Analog Scale [VAS]). METHODS: A comparative analysis was performed evaluating spinopelvic parameters and clinical outcomes including the ODI, VAS, and complications in patients who underwent PSO (PSO group; n=65) or multilevel prepsoas OLIF combined with PCO and open posterior spinal fusion using 6.35-mm CoCr rods (OLIF group; n=41). The authors have no conflicts of interest to disclose. RESULTS: There were no differences in preoperative spinopelvic parameters between the PSO and OLIF groups. Although no differences were observed between the two groups in terms of postoperative SVA (-12.66 mm vs. -16.44 mm), postoperative lumbar lordosis (-71.46° vs. -72.55°), lumbar lordosis correction (77.96° vs. 73.54°), or postoperative pelvic tilt (9.35° vs. 7.17°), the estimated blood loss was significantly lower in the OLIF group (2824 mL vs. 1736 mL, p<.05). No differences were observed in clinical outcomes (ODI, VAS, and clinical complications), proximal junctional kyphosis, and spinopelvic parameters between the two groups 2 years after surgery. However, pseudarthrosis during the follow-up period, including rod fracture, occurred less frequently in the OLIF group compared with that in the PSO group (p<.05). OLIF was performed from the T12-L1 to L5-S1 regions (124 segments), with an average of three segments per patient. The computed tomography scans immediately after surgery showed an average segmental correction of -18° and 12.9% (16 segments) of 124 segments showed a correction angle of >30°. CONCLUSIONS: Multilevel OLIF with PCO using a stiff rod to treat severe sagittal imbalance resulted in similar levels of sagittal balance and lordosis correction as obtained by PSO. Multilevel OLIF with PCO using a stiff rod can be an effective alternative to PSO for patients with severe sagittal imbalance.

Anterior lumbar interbody fusions combined with posterior column osteotomy in patients who had sagittal imbalance associated with degenerative lumbar flat-back deformity: a retrospective case series.

Anterior lumbar interbody fusion (ALIF) combined with posterior column osteotomy (PCO) may be effective to achieve ideal lumbar curve correction in lumbar flat-back deformity (LFD). We aimed to investigate the radiographic and clinical outcomes of patients with primary degenerative LFD treated with multi-level ALIFs combined with PCOs. Seventy patients with primary degenerative LFD who underwent corrective surgery were divided into three groups according to the 1-month postoperative pelvic incidence/lumbar lordosis (PI-LL) angles (≤ - 10°, from - 9° to 9°, and ≥ 10°). The spinopelvic parameters, including thoracic kyphosis, LL, pelvic tilt, T1 pelvic angle, and sagittal vertical axis, were analyzed at the preoperative, postoperative follow-up periods. The clinical outcomes, including the Oswestry disability index (ODI), visual analog scale (VAS), and Scoliosis Research Society (SRS)-22r, were also evaluated. Further, the paraspinal muscles were qualitatively and quantitatively examined, preoperatively. All spinopelvic parameters were corrected as close to the normal values at the 1-month postoperative period. The spinopelvic parameters in the PI-LL ≤ - 10° group were better corrected and maintained than those in the other groups. The ODI, VAS, and SRS-22r scores improved at the final follow-up in all groups. The PI-LL ≤ - 10° group showed better clinical outcomes than the other groups. In the paraspinal muscle examination, the mean lumbar muscularity value and fatty degeneration ratio were 236.7% and 20.7%, respectively. Multi-level ALIFs with PCOs in patients with LFD are effective in restoring sagittal balance and improving clinical symptoms. In addition, the postoperative LL angles should be larger than PI + 10° to achieve good overall outcomes in patients with severe degenerative back muscle.

Rod fracture after multiple-rod constructs for adult spinal deformity.

OBJECTIVE: This study investigated the incidence and risk factors of rod fracture (RF) after multiple-rod constructs (MRCs) for adult spinal deformity (ASD) surgery. METHODS: A single-center, single-surgeon consecutive series of adult patients who underwent posterior thoracolumbar fusion at 4 or more levels using MRCs after osteotomy with at least 1 year of follow-up were retrospectively reviewed. Patient characteristics, radiological parameters, operative data, and clinical outcomes (on the Scoliosis Research Society-22r questionnaire) were analyzed at baseline and follow-up. RESULTS: Seventy-six patients were enrolled in this study. RF occurred in 9 patients (11.8%), with all cases involving partial rod breakage. Seven patients (9.2%) underwent revision surgery. There were no significant differences in baseline demographic characteristics, radiological parameters, and surgical factors between the RF and non-RF groups. Multivariable analysis revealed that interbody fusion at the L5-S1 and L4-S1 levels could significantly reduce the occurrence of RF after MRCs for ASD (adjusted odds ratios 0.070 and 0.035, respectively). The RF group had significantly worse function score (mean 2.9 ± 0.8 vs 3.5 ± 0.7) and pain score (mean 2.8 ± 1.0 vs 3.5 ± 0.8) compared with the non-RF group at last visit. CONCLUSIONS: RF occurred in 11.8% of patients with MRCs after ASD surgery. Most RFs occurred at the lumbosacral junction or adjacent level (77%). Interbody fusion at the lumbosacral junction (L5-S1 or L4-S1 level) could significantly prevent the occurrence of RF after MRCs for ASD.

The "kickstand rod" technique for correction of coronal imbalance in patients with adult spinal deformity: initial case series.

OBJECTIVE: The objective of this study was to describe and evaluate a new surgical procedure for the correction of coronal imbalance (CI) in adult spinal deformity patients, called the "kickstand rod" technique. METHODS: The authors analyzed the records of 24 consecutive patients with pediatric and adult spinal deformity and CI treated between July 2015 and October 2017 with a long-segment fusion and a kickstand rod. For the kickstand rod technique, an iliac screw was placed on the ipsilateral side of the trunk shift and connected proximally through a side-by-side domino link to the thoracolumbar junction; this rod was distracted to promote coronal plane balancing. Distraction occurred with the rod on the contralateral side locked in order to preserve sagittal correction. Radiographic and clinical analyses were conducted to evaluate the outcomes and possible complications of the kickstand rod technique. RESULTS: The mean age of the patients was 55 years (range 14-73 years). Eighteen of the 24 patients were female. CI preoperatively was a mean of 63 mm, and the mean measurement at the final follow-up (mean duration 1.4 years) was 47 mm. There were no neurological, vascular, or implant-related complications in any of the patients. One patient developed wound dehiscence that was successfully treated without implant removal, and one developed proximal junctional kyphosis requiring extension of the construct proximally. One patient also returned to the operating room for excision of a spinous process. There were no complaints about screw prominence, kickstand construct failure, or significant worsening of CI after surgery. CONCLUSIONS: The kickstand rod technique is safe and effective for the correction of CI in spinal deformity patients. This technique was found to provide marked coronal correction and additional strength to the overall construct without significant adverse consequences.

Factors for the acquisition of 10° angular change at the lumbar spine through posterior column osteotomy in adult spinal deformity surgery.

OBJECTIVEPosterior column osteotomy (PCO) has been known to provide an angular change (AC) of approximately 10° in sagittal plane deformity. However, whether PCO can actually obtain an AC of ≥ 10° depending on the particular level in the lumbar spine and which factors can effect a gain of ≥ 10° AC after PCO remain to be elucidated. The aim of this study was to identify the factors that effect a gain of ≥ 10° AC through PCO by comparing radiographic measurements between an AC group and a control group before and after adult spinal deformity (ASD) surgery.METHODSForty consecutive patients who underwent multilevel PCOs for ASD at a single institution between 2012 and 2016 were included in this study. PCO was performed in 142 disc space levels in the lumbar spine. The authors defined the disc space level that obtained ≥ 10° AC in the sagittal plane by PCO as the AC group and the remaining patients as controls. The modified Pfirrmann grade, surgical level, implementation of the transforaminal lumbar interbody fusion (TLIF), and radiographic measurements were compared between the groups.RESULTSThere were 67 levels in the AC group and 75 in the control group. Multivariate analysis identified the surgical level at L4-5 (OR 3.802, 95% CI 1.127-12.827, p = 0.031), performing TLIF with PCO (OR 3.303, 95% CI 1.258-8.674, p = 0.015), and a preoperative kyphotic disc space angle (OR 1.397, 95% CI 1.231-1.585, p < 0.001) as the factors that significantly effected ≥ 10° AC in the sagittal plane after PCO.CONCLUSIONSIn ASD surgery, PCO cannot always achieve ≥ 10° AC in the sagittal plane. The factors that effected ≥ 10° AC in PCO for ASD were surgical level at L4-5, performing TLIF with PCO, and the preoperative kyphotic disc space angle.

The comprehensive anatomical spinal osteotomy and anterior column realignment classification.

OBJECTIVESpinal osteotomies and anterior column realignment (ACR) are procedures that allow preservation or restoration of spine lordosis. Variations of these techniques enable different degrees of segmental, regional, and global sagittal realignment. The authors propose a comprehensive anatomical classification system for ACR and its variants based on the level of technical complexity and invasiveness. This serves as a common language and platform to standardize clinical and radiographic outcomes for the utilization of ACR.METHODSThe proposed classification is based on 6 anatomical grades of ACR, including anterior longitudinal ligament (ALL) release, with varying degrees of posterior column release or osteotomies. Additionally, a surgical approach (anterior, lateral, or posterior) was added. Reliability of the classification was evaluated by an analysis of 16 clinical cases, rated twice by 14 different spine surgeons, and calculation of Fleiss kappa coefficients.RESULTSThe 6 grades of ACR are as follows: grade A, ALL release with hyperlordotic cage, intact posterior elements; grade 1 (ACR + Schwab grade 1), additional resection of the inferior facet and joint capsule; grade 2 (ACR + Schwab grade 2), additional resection of both superior and inferior facets, interspinous ligament, ligamentum flavum, lamina, and spinous process; grade 3 (ACR + Schwab grade 3), additional adjacent-level 3-column osteotomy including pedicle subtraction osteotomy; grade 4 (ACR + Schwab grade 4), 2-level distal 3-column osteotomy including pedicle subtraction osteotomy and disc space resection; and grade 5 (ACR + Schwab grade 5), complete or partial removal of a vertebral body and both adjacent discs with or without posterior element resection. Intraobserver and interobserver reliability were 97% and 98%, respectively, across the 14-reviewer cohort.CONCLUSIONSThe proposed anatomical realignment classification provides a consistent description of the various posterior and anterior column release/osteotomies. This reliability study confirmed that the classification is consistent and reproducible across a diverse group of spine surgeons.

Treatment strategy for rod fractures following corrective fusion surgery in adult spinal deformity depends on symptoms and local alignment change.

OBJECTIVE Despite the significant incidence of rod fractures (RFs) following long-segment corrective fusion surgery, little is known about the optimal treatment strategy. The objectives of this study were to investigate the time course of clinical symptoms and treatments in patients with RFs following adult spinal deformity (ASD) surgery and to establish treatment recommendations. METHODS This study was a retrospective case series of patients with RFs whose data were retrieved from a prospectively collected single-center database. The authors reviewed the cases of 304 patients (mean age 62.9 years) who underwent ASD surgery. Primary symptoms, time course of symptoms, and treatments were investigated by reviewing medical records. Standing whole-spine radiographs obtained before and after RF development and at last follow-up were evaluated. Osseous union was assessed using CT scans and intraoperative findings. RESULTS There were 54 RFs in 53 patients (mean age 68.5 years [range 41-84 years]) occurring at a mean of 21 months (range 6-47 months) after surgery. In 1 patient RF occurred twice, with each case at a different time and level, and the symptoms and treatments for these 2 RFs were analyzed separately (1 case of revision surgery and 1 case of nonoperative treatment). The overall rate of RF observed on radiographs after a minimum follow-up of 1 year was 18.0% (54 of 300 cases). The clinical symptoms at the time of RF were pain in 77.8% (42 of 54 cases) and no onset of new symptoms in 20.5% (11 of 54 cases). The pain was temporary and had subsided in 19 of 42 cases (45%) within 2 weeks. In 36 of the 54 cases (66.7%) (including the first RF in the patient with 2 RFs), patients underwent revision surgery at a mean of 116 days (range 5-888 days) after diagnosis. In 18 cases patients received only nonoperative treatment as of the last follow-up, including 17 cases in which the patients experienced no pain and no remarkable progression of deformity (mean 18.5 months after RF development). CONCLUSIONS This analysis of 54 RFs in 53 patients following corrective fusion surgery for ASD demonstrates a relationship between symptoms and alignment change. Revision surgeries were performed in a total of 36 cases. Nonoperative care was offered in 18 (33.3%) of 54 cases at the last follow-up, with no additional symptoms in 17 of the 18 cases. These data offer useful information regarding informed decision making for patients in whom an RF occurs after ASD surgery.

Multilevel Posterior Column Osteotomies Are Not Inferior For the Correction of Rigid Adult Spinal Deformity Compared with Pedicle Subtraction Osteotomy.

BACKGROUND: Posterior column osteotomy (PCO) has been used for the correction of various spinal deformities. However, little evidence is available regarding the effects of multilevel PCO in adult spinal deformity (ASD) surgery. This study aimed to show the usefulness of PCO in rigid ASD surgery by assessing radiographic and clinical outcomes. We also aimed to assess the corrective potential of multilevel PCOs compared with a single-level pedicle subtraction osteotomy (PSO). METHODS: Between 2012 and 2016, the medical records of 70 consecutive patients who underwent a multilevel PCO (35 patients) or a single-level PSO (35 patients) for ASD in a single institute were reviewed. Baseline data, radiographic measurements, and clinical outcomes using the Scoliosis Research Society-22 (SRS-22) questionnaire were compared between groups. RESULTS: The following variables were no different between the groups: age at surgery, sex, level fused, preoperative and postoperative radiologic parameters, and bone mineral density T score. However, operation time (380.0 vs. 483.6 minutes), estimated blood loss (1175.7 vs. 1362.6 mL), and the number of complications (8 vs. 20) were significantly reduced in the PCO group compared with the PSO group. A significant improvement in the SRS-22 score was seen in both groups after surgery, although no difference was observed between the groups postoperatively. CONCLUSIONS: Multilevel PCOs for the correction of rigid ASD were slightly superior to PSO, regarding clinical outcomes. Radiographic outcomes were similar between groups. Thus, multilevel PCOs may be a viable option for the treatment of rigid ASD with a mobile segment.

Posterior Versus Three-Column Osteotomy for Late Correction of Residual Coronal Deformity in Patients With Previous Fusions for Idiopathic Scoliosis.

STUDY DESIGN: Retrospective case series. OBJECTIVE: To compare the early results of posterior column (PCO) and three-column (3CO) osteotomies performed in patients with previously fused idiopathic scoliosis and review their abilities to achieve coronal correction of residual deformities. SUMMARY OF BACKGROUND DATA: Residual deformity of previously fused AIS can accelerate adjacent segment degeneration secondary to lowest instrumented vertebra (LIV) tilt and rotation. Many of these patients are not satisfied with their cosmetic appearance and would choose revising the deformity when future surgery is indicated. METHODS: The data from 29 consecutive patients who underwent PCOs or 3COs for late revisions of idiopathic scoliosis were reviewed. Measurements included Cobb angle, focal osteotomy angle, and coronal balance. Perioperative data, complications, and patient-reported outcomes were also reviewed. RESULTS: Fourteen patients were treated with PCOs and 15 with 3COs. Global coronal correction was equal between the two groups. In the PCO group, where patients underwent a mean of 2.4 osteotomies, 20.2° of correction was obtained compared to 19.5° in the 3CO group (p = .33), which all underwent single osteotomies. The average coronal correction was 9.2°/osteotomy for the PCO group and 14.1°/osteotomy for the 3CO group (p < .01). Estimated blood loss was 1,417.5 mL in the PCO group compared to 3,199.3 in the 3CO group (p < .01). Five patients (36%) had intraoperative complications in the PCO group compared to 12 (80%) in the 3CO group (p < .05). There were no differences in operative times, length of stay, or patient-reported outcomes between groups. CONCLUSION: PCOs and 3COs performed in patients with previously fused spines for idiopathic scoliosis are effective in achieving residual deformity correction. In cases of posterior fusions, where the patient has a mobile anterior column, PCOs should be considered over 3COs because of their decreased risk of blood loss and complications.