Sagittal Plane Deformity Correction Research Articles

Effect of Anterior Tibial Closing Wedge Osteotomy on Coronal Tibial Alignment in Relation to Preoperative Medial Proximal Tibial Angle and Wedge Height.

The posterior tibial slope has been identified as an anatomic risk factor for anterior cruciate ligament insufficiency and reruptures after anterior cruciate ligament reconstruction. Anterior tibial closing wedge osteotomy for correction of sagittal plane deformities has the potential to cause an unintended change in coronal plane alignment. To evaluate the effects of anterior tibial closing wedge osteotomies for correction of posterior tibial slope on coronal plane alignment using an infratuberosity surgical approach and to identify predictive factors for a change in medial proximal tibial angle (MPTA). Case series; Level of evidence, 4. This study reports on retrospectively obtained data from radiographic measurements of 38 anterior tibial closing wedge osteotomies. All patients underwent revision anterior cruciate ligament reconstruction and had undergone ≥1 previous anterior cruciate ligament reconstruction. In all patients, an infratuberosity approach was used with angular stable plate fixation. Pre- and postoperative radiographs were examined retrospectively to detect changes in the sagittal and coronal plane alignment (posterior tibial slope and MPTA). A multivariate regression analysis was used to identify predictors for a change in MPTA. The study group consisted of 14 women and 24 men whose mean ± SD age at the index procedure was 31.6 ± 8.7 years (range, 17-51 years). Posterior tibial slope decreased significantly (by 7.2° ± 2.3°; P < .001) from 14.6° ± 2.0° preoperatively to 7.4° ± 2.1° postoperatively. MPTA decreased significantly by 1.3° ± 1.5° (P = .005) from pre- to postoperative measurement. Mean wedge height was 9.3 ± 1.1 mm. A lower preoperative MPTA (coefficient = 0.32; P = .017; 95% CI, 0.06-0.59) and larger wedge height (coefficient = 0.48; P = .029; 95% CI, 0.05-0.9) were significant predictive factors for a decrease in MPTA. Anterior tibial closing wedge osteotomy for posterior tibial slope reduction resulted in a slight but significant decrease of the MPTA in the coronal plane. These changes were dependent on the preoperative MPTA and the wedge height.

The 'candy cane' technique for construct augmentation and correction of severe angular chin-on-chest kyphoscoliosis.

To manage severe angular chin-on-chest deformity. A single midline incision and periosteal dissection were utilized to expose from C2 to T6. Bilateral C2 pars screws, C3 to C7 lateral mass screws, and T1 to T6 pedicle screws were placed. Following the placement of screws, multiple two column posterior osteotomies and interlaminar decompressions from C6 to T3 were performed to amplify both the sagittal and coronal corrections. Titanium rods were utilized in light of the patient's known osteopenia and nickel allergy. As such, the construct was augmented via the use of a third accessory rod. This third titanium rod was placed into a supplementary translaminar screw with three connectors to the right-sided main rod. Once the lordotic configuration of the contralateral main rod was secured, an additional corrective maneuver of gentle distraction across this third rod was employed to assist with coronal correction. In this patient with osteopenia, a known nickel allergy, and significant cervical imbalance, the Candy Cane construct allowed for a durable correction of the severe sagittal and coronal plane deformity. The chin-brow angle was corrected by 44°. The coronal Cobb angle improved by 10°. On long-term follow-up, the patient reported continued satisfaction with the operation and was able to perform his activities of daily living. A one-stage, posterior approach along with construct augmentation, with a third rod hooked into a supplementary C2 translaminar screw, can be employed for the correction of chin-on-chest kyphoscoliosis.

Top-ten most-cited articles on anterior column release in the context of minimally invasive lumbar interbody fusion.

Lateral anterior column release (ACR) is a minimally invasive option for the correction of sagittal plane deformity. To assemble a homogeneous picture of published research on ACR, an advanced bibliometric analysis was conducted to compile the top-ten most-cited articles on the topic of ACR. A keyword search using the Thomson Reuters Web of Knowledge was conducted to identify articles discussing the role of lateral ACR. The articles were then ranked based on the total number of citations to identify the ten most-cited articles published. A subjective appraisal of the findings of these articles was conducted to provide a ranked literature review and to examine trends in the study of ACR between 2012 and 2019. The earliest published article on ACR was in 2012 by Deukmedjian et al. Three articles were in vitro biomechanical assessments of ACR, and seven articles were on outcome analyses, which were either case series or case controlled. The most-cited article was a biomechanical study authored by Uribe et al. The article with the highest rate of citations/year was authored by Manwaring et al. Uribe and the European Spine Journal were the most frequently cited author and journal, respectively. The lateral ACR approach has enjoyed significant scholarly attention since its advent. Higher-level analyses with robust control groups, larger sample sizes, and long-term follow-up are necessary to improve our understanding of this approach.

Charcot Arthropathy Limb Salvage with 3D Custom Cage and Dynamic Hindfoot Fusion Nail Combination Fixation: A Case-Series

Category: Diabetes; Ankle; Hindfoot Introduction/Purpose: Patients with Charcot arthropathy with hindfoot collapse present a difficult challenge for foot and ankle surgeons. While traditional limb salvage options include tibiotalocalcaneal (TTC) arthrodesis with accepted shortening, thin wire external fixation, or TTC arthrodesis with bulk femoral head allograft, new 3-dimensional (3D) custom patient specific implants offer a new treatment modality for limb salvage for this difficult issue. The purpose of this case-series is to offer one surgeon's experience with this new treatment technique for limb salvage. Methods: All patients undergoing limb salvage procedures for hindfoot collapse between 2018 and 2022 with a custom 3D hindfoot cage with TTC hindfoot fusion intramedullary nail were included for analysis. Along with patient demographics and length of follow up, patients were asked a series of questions on a telephone survey in order to measure patient reported outcomes including current ambulatory status and whether they would have elected to undergo the same treatment modality again. Complications were also tracked. Finally, radiographs were analyzed to evaluate the degree of deformity correction on both coronal and sagittal planes as well as degree of deformity correction maintenance at last radiographic follow up. Results: 13 patients were included in the analysis. 10 of the 13 patients had Charcot arthropathy. 2 patients had deep infections that ultimately required below knee amputation. 11 out of 13 patients had successful limb salvage as defined by the maintenance of a functional limb without need for amputation. Interestingly, both patients who failed limb salvage and required below knee amputations reported that they would prefer to have undergone the same attempt at limb salvage even with the resulting amputation. Radiographically, the average amount of coronal plane deformity correction was 25 degrees while the average amount of sagittal plane deformity correction was 6 degrees. The average amount of deformity correction maintenance seen at last radiographic follow up was high with a loss of only 0.5 degrees in coronal plane deformity correction loss throughout the time period and an average of 2 degrees of sagittal plane deformity correction loss. Conclusion: While still a challenging pathology to treat, custom patient specific 3D implants combined with TTC hindfoot fusion nail is a viable construct for patients with Charcot arthropathy undergoing limb salvage for hindfoot collapse.

Kinematic and biomechanical responses of the spine to distraction surgery in children with early onset scoliosis: A 3-D finite element analysis.

Periodical and consecutive distraction is an effective treatment for severe early onset scoliosis (EOS), which enables the spinal coronal and sagittal plane deformity correction. However, the rate of rod fractures and postoperative complications was still high mainly related to the distraction process. Previous studies have primarily investigated the maximum safe distraction force without a rod broken, neglecting the spinal re-imbalance and distraction energy consumption, which is equally vital to evaluate the operative value. This study aimed to reveal the kinematic and biomechanical responses occurring after spinal distraction surgery, which were affected by traditional bilateral fixation. The spinal models (C6-S1) before four distractions were reconstructed based on CT images and the growing rods were applied with the upward displacement load of 0–25 mm at an interval of 5 mm. Relationships between the distraction distance, the distraction force and the thoracic and lumbar Cobb angle were revealed, and the spinal displacement and rotation in three-dimensional directions were measured. The spinal overall imbalance would also happen during the distraction process even under the safe force, which was characterized by unexpected cervical lordosis and lateral displacement. Additionally, the law of diminishing return has been confirmed by comparing the distraction energy consumption in different distraction distances, which suggests that more attention paid to the spinal kinematic and biomechanical changes is better than to the distraction force. Notably, the selection of fixed segments significantly impacts the distraction force at the same distraction distance. Accordingly, some results could provide a better understanding of spinal distraction surgery.

Lateral lumbar deformity correction and outcomes

Minimally invasive surgery for adult spinal deformity has become an increasingly popular technique to treat this complex patient population. The use of lateral lumbar interbodies fusion has become the most valuable technique to achieve deformity correction by manipulating the anterior column. The LLIF technique allows for both coronal and sagittal plane deformity correction while providing a large load bearing surface for stability and an optimal environment for fusion. If severe sagittal plane deformities are encountered then the anterior column realignment technique with release of the anterior longitudinal ligament can be used in carefully selected patients to achieve the desired alignment goals. Ultimately patient selection and surgeon experience will play an important role in the successful completion of minimally invasive LLIF for adult spinal deformity

Two-Year Outcomes After Total Ankle Replacement With a Novel Fixed-Bearing Implant.

The Integra Cadence total ankle replacement (TAR) is a fourth-generation anatomic, fixed-bearing implant requiring minimal tibial and talar resection, which has been in clinical use since June 2016. The primary purpose of this study is to assess its short-term clinical and radiographic outcomes after TAR using this prosthesis. This is a prospective case series of consecutive patients that underwent TAR using this novel fourth-generation prosthesis between June 2016 and November 2017. The primary outcome of interest was the Ankle Osteoarthritis Scale (AOS). Secondary outcomes included Short Form Health Survey-36 (SF-36) scores, radiographic alignment, complications, reoperations, and revisions. In total, 69 patients were included in our study. Fifty-one patients (73.9%) required a total of 91 ancillary procedures. Postoperatively, AOS pain scores decreased significantly by an average of 17.8±30.1 points from 45.9±18.2 to 28.4±27.3 (P < .001). AOS disability scores also decreased significantly following surgery by an average of 22.0±30.5 points from 53.9±18.5 to 32.5±27.9 (P < .001). The SF-36 physical component summary score improved 10.4±9.8 points from 33.1±9.1 to 42.6±9.1 (P < .001). Radiographic analysis demonstrated significant improvement to neutral coronal plane alignment, which was achieved in 97% of patients (P < .01) with no cyst formation at 2 years. There was 1 reported complication, 9 reoperations, and no metal or polyethylene component revisions. Overall, the 2-year implant survivorship was 100% in our cohort. Eighteen patients (26.1%) demonstrated fibrous ingrowth of the tibial component. However, outcome scores for these patients did not demonstrate any negative effects. In our hands, this TAR system demonstrated excellent early clinical and radiographic outcomes. Patients reported improved physical health status, pain, and disability in the postoperative period. Total ankle instrumentation allowed for accurate and reproducible implantation with correction of coronal and sagittal plane deformities. Early results for the clinical use of this TAR system are promising, but further long-term prospective outcome studies are necessary. Level IV, case series.

Foot Deformity Correction Planning in the Sagittal Plane Based on the Vitruvian Foot First Metatarsal Mechanical Axis and Calcaneus Anatomic Axis

The aim of the study was to test a novel planning method for simultaneous midfoot and hindfoot deformity correction, based on reference lines and angles (RLA) of the talus, calcaneus and first metatarsal in 64 normal radiographs from 55 patients. Talus Joint Line (TJL), from the border of the articular surface of the talus and the posterior process of talus, and mechanical axis of the first metatarsal form the mechanical Lateral Talometatarsal Angle (mLTMA)=23.6º (±3.2). The length of the first metatarsal line was measured from its intersections with the TJL and first metatarsal head and it was 4.3 (±0.94) times longer that TJL (k). For hindfoot correction planning, we used an axis of the calcaneus formed by a line starting at the middle of the back of the calcaneal tuberosity and going perpendicular to a line from the top point to the bottom point of the calcaneal tuberosity. The intersection of the calcaneal line and the anterior continuation of TJL form the lateral heel angle (LHA)=15.2º (±3.4).The following parameters were identified: the length from the intersection point of the lines and anterior point of TJL was 2.56 ± 1.1 longer than TJL (k1). The length from the intersection point and posterior border of the calcaneus was 4.59 ± 1.0 times longer than TJL (k2). Planning using the new method was demonstrated and confirmed on 3 case examples. A novel method for analysis and planning of midfoot and hindfoot sagittal plane deformity correction may be used separately or simultaneously for complex deformity correction.

Transforaminal lumbar interbody fusion in iatrogenic lumbar instability

Background Lumbosacral instability is one of the causes of failed back surgery syndrome, and it is characterized by loss of disc height with translational and in many cases rotational instability in the sagittal plane. Transforaminal lumbar interbody fusion (TLIF) is a modification of posterior lumbar interbody fusion that requires less retraction of the thecal sac and neural element. TLIF corrects most of the pathologies in patients with iatrogenic lumbar instability as it provides rigid stabilization of the spine with high incidence of fusion, decompression of central and lateral recess with facet and disc resection, restoration of disc and foraminal heights together with sagittal plane deformity correction. Aim This study was carried out to evaluate the efficacy of TLIF in the treatment of patient with iatrogenic lumbar instability. Patients and methods A total of 16 cases were diagnosed as iatrogenic lumbar instability according to the radiological method proposed by Dupuis and colleagues. Sex distribution was nine females and seven males. Plain radiograph (static and dynamic) and MRI with gadolinium enhancement were done for all patients. Single-level transforaminal lumbar interbody fusion (TILF) was performed in 11 cases and double-level TLIF was performed in five cases. Clinical evaluation was made using Oswestry disability index. Patients were examined for occurrence of solid interbody fusion at 9- and 12-month follow-up visits. Result A total of 14 patients showed obvious clinical improvement with reduction of their Oswestry disability index from 76.75% preoperatively to 36.9% at 6 month and 22.7% after 1 year. Overall, two cases had shown no clinical improvement: one had deep wound infection and the other had pseudoarthrosis. Solid fusion occurred in 14 (87.5%) cases. One case with pseudoarthrosis was the patient who had developed deep wound infection; the other case was a patient undergoing double-level TILF with pseudoarthrosis at L5–S1. Conclusion TLIF is a safe and effective technique in the treatment of patients with postlaminectomy lumbar instability with minimal complication rate.

Prediction of leg length change (LLC) after correcting varus and flexion deformity in patients undergoing TKA.

Patients with varus and fixed flexion deformity (FFD) undergoing TKA may have a significant leg length change (LLC) after surgery. We aimed to determine the correlation between changes in HKA or FFD and leg length in patients undergoing TKA, the combined effect of coronal and sagittal plane deformity correction on LLC, and the possibility of estimating LLC mathematically. This was a prospective radiographic evaluation of 242 knees, which had undergone primary unilateral TKA for advanced OA with varus and FFD. Full-length standing calibrated anteroposterior radiographs were used to measure the hip-knee-ankle axis (HKA) and functional leg length after adjusting for magnification. Clinical evaluation of FFD was done using a handheld goniometer. 224 knees (92.6%) showed increased limb length after TKA averaging 10.7mm (SD 9.5mm, P = .000). There was a significant correlation between the change in HKA and FFD from preoperatively to postoperatively with the amount of LLC (ρ 0.326 and 0.346, respectively, P = .000). FFD improvement from preoperatively to postoperatively was 8.1° to 1° (P = .000), respectively. A linear relationship was established between LLC and changes in HKA and FFD, where 10° improvement in HKA would result in an LLC of nearly 4mm, and 10° improvement in FFD would result in a LLC of nearly 8mm. LLC may be substantial after correcting varus and FFD with unilateral TKA, it correlates with the change in HKA and FFD and can be mathematically estimated. CLINICAL TRIALS . NCT03502382.

296. Residual coronal malalignment results in less improvement in pain and disability after ASD surgery

BACKGROUND CONTEXT Prior literature has demonstrated that correction of sagittal plane deformity in adult patients has resulted in improvements in health-related quality of life (HRQOL) outcomes. In the absence of sagittal plane pathology, the effects of coronal malalignment under-correction in patients with spinal deformity have not been fully investigated. PURPOSE To evaluate the impact of coronal malalignment correction on HRQOL outcomes in adult spinal deformity. STUDY DESIGN/SETTING Retrospective review of a multicenter database. PATIENT SAMPLE A total of 522 ASD patients had preoperative coronal malalignment greater than 40 mm. We excluded anyone who had SVA greater than 50 mm in order to control for patients without severe sagittal deformities. OUTCOME MEASURES Our outcome measures included Oswestry Disability Index (ODI), SF-36 Physical Component Summary (PCS), and several other SF-36 and SRS-22r health domains scores. METHODS Using a prospective, multicenter database, we identified 1560 surgical patients. Of these, 522 patients had preoperative coronal malalignment greater than 40 mm. We excluded anyone who had SVA greater than 50 mm in order to control for patients who only had coronal plane deformity. We only included patients undergoing primary surgery. We then compared 2-year post HRQOL outcomes in patients that had their coronal malalignment corrected (CVA RESULTS Mean age of patients was 54 ± 15 years, 91% females. 79 patients were identified with only a coronal plane deformity undergoing a primary ASD surgery. Of these, 38 (48%) were under-corrected and 41 (52%) had their coronal alignment corrected to CONCLUSIONS Patients with coronal malalignment and little sagittal plane deformity experience worse improvement in pain and disability, with under-correction of their coronal plane deformity. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Foot Deformity Correction Planning in the Sagittal Plane Based on the Vitruvian Foot First Metatarsal Anatomic Axis

The aim of this study was to test a novel planning method for midfoot deformity correction, based on reference lines and angles (RLA) of talus and first metatarsal of 64 normal radiographs from 55 patients. The anatomic lateral talometatarsal angle (aLTMA), resulting from the intersection of talus joint line (TJL), from the border of the articular surface of the talus to the posterior process of talus, and the anatomic axis of the first metatarsal, was 28.5° ± 4.5°. The intersection of those 2 lines divided the TJL in 2 segments (ac and ab) with the ratio k1 = 0.7 ± 0.3. The length of the first metatarsal line was measured from its intersection with the TJL and first metatarsal head, and it was 3.6 times longer that of the TJL (k2). To analyze foot deformity, we propose to draw the TJL line as follows. Use the k1 ratio to determine the point where the aLMTA intersects the TJL. From this point, an idealized anatomic first metatarsal line should be drawn, at 28.5° from the TJL. The distal end of that line is based on the k2 ratio (3.6 × TJL length). Next, the actual anatomic lateral talometatarsal line of the deformed foot is drawn. The intersection between these 2 lines identifies the apex and magnitude of the deformity. Deformity correction planning using the proposed method was demonstrated and confirmed in 2 cases. A reference method for analysis and planning of midfoot sagittal plane deformity correction independent of foot position relative to the ankle joint or the presence of concomitant hindfoot deformity appears promising for future investigation and use.

Obesity Is Associated With Increased Thoracic Kyphosis in Adolescent Idiopathic Scoliosis Patients and Nonscoliotic Adolescents

Study DesignRetrospective comparative cohort study. ObjectiveTo compare radiographic parameters between adolescents with a greater body mass index (BMI) percentile to underweight individuals. Summary of Background DataIncreased BMI percentile has been associated with increased complications after surgical correction of adolescent idiopathic scoliosis (AIS). However, association between BMI percentile and preoperative sagittal plane alignment has not been evaluated. The purpose of this study was to evaluate the effect of BMI percentile on sagittal alignment in AIS patients compared with nonscoliotic adolescents. MethodsPosterior-anterior and lateral spinal radiographs of 1,551 AIS patients with a thoracic major curve (Lenke 1–4) and 70 nonscoliotic adolescent patients were compared. BMI percentile was determined based on age and sex, and patients were divided into four categories: underweight (<5th percentile), normal-weight (5th–85th percentile), overweight (85th–95th percentile), and obese (≥95th percentile). ResultsCoronal plane deformity magnitude was not significantly different between the 4 categories of AIS patients (p = .51). Increased BMI percentile was associated with increased thoracic kyphosis globally (T2–T12: p < .005) as well as segmentally (T2–T5: p < .001; T5–T12: p < .001) in patients with AIS. This was also true in obese adolescents without spinal deformity (p < .04). Lumbar lordosis, pelvic incidence, and pelvic tilt were not significantly different between AIS patients in the four BMI percentile categories (p > .07). Pelvic incidence was significantly greater in AIS patients compared with nonscoliotic adolescents (54 ± 13 vs. 46 ± 11; p = .01). ConclusionIncreased BMI percentile is associated with increased thoracic kyphosis in AIS patients and nonscoliotic adolescents. Excess weight may reduce anterior vertebral growth. AIS patients have an increased pelvic incidence compared with nonscoliotic adolescents; however, this variable is not influenced by body mass. These relationships should be taken into account when planning sagittal plane deformity correction or considering neuro axis disorders (also associated with increased kyphosis) in patients with scoliosis. Level of EvidenceLevel II.

Anterior Column Reconstruction vs Pedicle Subtraction Osteotomy for Severe Sagittal Plane Deformity: Early Clinical and Radiographic Outcomes Using a Hyperlordotic Expandable Lateral Interbody Device

Abstract INTRODUCTION Anterior Column Reconstruction (ACR) is an increasingly utilized minimally invasive alternative to Pedicle Subtraction Osteotomy (PSO) for correction of sagittal plane deformity in patients with an available unfused lumbar disc. METHODS Fifteen consecutive patients with significant sagittal plane imbalance (SVA &gt; 10 cm or PI-LL mismatch/planned correction &gt; 30?) after prior lumbar fusion were analyzed. Patients underwent either an ACR (N = 11) using an expandable, hyperlordotic lateral interbody device if possible via an unfused disc space, or PSO (n = 4). RESULTS There were no significant differences between the baseline sagittal parameters in the ACR and PSO groups: PI: 59.09? vs 57.67?, P = .88; LL 18.36? vs 28.50?, P = .38; PT: 32.72? vs 37.00?, P = .64; SVA: 12.72 cm vs 11.95 cm P = .77; segmental angulation 2.72? vs 2.75?, P = .99. ACR produced significant improvements in sagittal parameters after surgery compared with preoperative parameters: LL 55.27?, P = .0001; Pi-LL Mismatch 3.45?, P = .0001; PT 22.45?, P = .0254; SVA 4.621 cm P = .0019; segmental angle 25.09?, P &lt; .0001. PSO also produced significant segmental lordosis (29.00?, P = .0032), which was not significantly different from the correction achieved by ACR (25.09? vs 29.00?, P = .47). In ACR, an average of 24.31? of lordosis was achieved at the index level, with an average cage expansion of 24.08?. There was no significant difference in the number of levels fused posteriorly between the ACR and PSO groups (7 vs 8.75 levels, P = .175) or length of surgery (375.25 min vs 370.5 min, P = .47). However, there was significantly less blood loss in the ACR group (311.15 mL vs 962.5 mL, P = .0004) and shorter length of stay (7.41 d vs 11 d, P = .034). CONCLUSION ACR with a hyperlordotic, expandable lateral interbody cage for significant sagittal deformity produced an equivalent degree of sagittal correction to PSO with significantly less blood loss and shorter hospital length of stay.

Anterior Column Realignment (ACR) With and Without Pre-ACR Posterior Release for Fixed Sagittal Deformity

Multiple studies have demonstrated a strong correlation between sagittal malalignment and health-related quality of life measures. Thus, correction of sagittal vertical axis (SVA), pelvic tilt (PT), lumbar lordosis-pelvic incidence (LL-PI), and T1 spinopelvic inclination (T1SPi) have become a primary objective of adult spinal deformity surgery. Anterior column realignment (ACR) has emerged as a less invasive technique and while the addition of posterior osteotomies has shown greater correction in ACR, it is unknown if a pre-ACR posterior release is necessary for optimal correction. The purpose of this study was to determine if pre-ACR posterior release allows for greater sagittal deformity correction. Seventeen patients were identified that underwent minimum 1-level ACR. Ten patients underwent an anterior-posterior surgical sequence without a pre-ACR posterior release, and 7 underwent a posterior-anterior-posterior (PAP) sequence with a pre-ACR posterior release. Radiographic outcomes at final follow-up and complications were compared. Both groups saw significant improvements in LL, LL-PI, PT, SVA, and T1SPi but the correction was not significantly different between cohorts. With the exception of PT in the PAP group, the improvements in LL-PI, PT, and SVA correlated to improvement in Scoliosis Research Society-Schwab classification. The correction achieved at the ACR level, represented by motion segment angle, was greater in the PAP group by a degree that approached statistical significance. Five patients (29%) had 6 complications. Both techniques achieved meaningful improvements in overall sagittal alignment. Our results suggest that a pre-ACR posterior release may allow for greater correction specifically at the ACR level but may not always be necessary to achieve clinically meaningful correction of sagittal plane deformity. 3. We present our experience with and without pre-ACR posterior release. To our knowledge, this is the first study to show that pre-ACR posterior release may achieve greater correction at the ACR level.

Lumbar Interbody Fusion for Adjacent Segment Disease: An illustrative Case of The Lateral Transpsoas Approach (XLIF-DLIF)

Adjacent segment disease (ASD) is a known complication of lumbar spine arthrodesis and refers to any type of deterioration at the adjacent cephalad or caudad motion segment to a prior fusion. The existing literature points to a multifactorial etiology including alterations of the physiologic biomechanics after fusion as well as the intrinsic spondylosis present at the time of the index operation. Revision posterior laminectomy and fusion can be technically challenging and has a higher complication rate than primary decompression and fusion procedures.Lateral lumbar interbody fusion (LLIF) along with posterior extension of fusion in a hybrid technique provides a less invasive option for the surgical treatment of ASD. Adjacent level stenosis is addressed via indirect decompression of the central canal and foramina. In addition, an assortment of cages provides relative correction of coronal and sagittal plane deformity. This manuscript discusses the role of LLIF for the treatment of ASD and two illustrative cases are presented.

Multiplanar Correction of the Lesser Digital Deviation and Indirect Plantar Plate Rupture Repair Using a Braided Polyethylene Nylon Suture: A Technique Guide.

Level V: Expert opinion.

A Critical Analysis of Sagittal Plane Deformity Correction With Minimally Invasive Adult Spinal Deformity Surgery: A 2-Year Follow-Up Study

IntroductionSagittal plane realignment is important to achieve desirable clinical outcomes after adult spinal deformity (ASD) surgery. This study evaluates the impact of minimally invasive (MIS) techniques on sagittal plane alignment and clinical outcomes in ASD patients. MethodsA retrospective, multi-center review of ASD patients (age ≥18 years, and with one of the following: coronal Cobb ≥20°, sagittal vertical axis [SVA] >5 cm, and/or pelvic tilt >25°), MIS surgery, and four or more levels instrumented. Patients were stratified by baseline SRS-Schwab global alignment modifier (GAM) into three groups: 0 (SVA <4 cm), + (SVA 4–9.5 cm), or ++ (SVA >9.5 cm). Radiographic and clinical outcomes measures were analyzed with a minimum of 2-year follow-up. ResultsA total of 96 ASD patients were identified, and 63 met the study's inclusion criteria of circumferential MIS or posterior MIS only, with four or more levels instrumented (n: Group 0 = 37, Group + = 15, and Group ++ = 11). Group 0 was younger than ++ (56.8 vs. 69.6 years), with a higher proportion of females than Group + or ++ (83.8% vs. 66.7% and 54.5%, respectively).Baseline HRQoL was similar. Postoperatively, Groups 0 and + had improved Oswestry Disability Index (ODI) and numeric rating scale (NRS) back and leg scores. Group ++ only had improvement in NRS scores. At the latest follow-up, Groups 0 and ++ had similar sagittal measurements except for PT (21.6 vs. 23.6, p = .009). The + group had improvement in PI–LL (24.2 to 17; p = .015) and LL (30.9 to 38.3; p = .013). Eight of 27 (21.6%) Group 0 patients deteriorated (4 to Group +, 4 to Group ++). Three of 15 (20.0%) Group + patients deteriorated to Group ++, and 3 improved to Group 0. Six of 11 (54.5%) Group ++ patients improved (3 to Group + and 3 to Group 0). ConclusionsMIS techniques successfully stabilized ASD patients with Group 0 and + deformities and improved HRQoL. This study suggests that severe sagittal imbalance is not adequately treated with MIS approaches.

Anterior Column Realignment has Similar Results to Pedicle Subtraction Osteotomy in Treating Adults with Sagittal Plane Deformity.

Anterior column realignment (ACR) is a minimally invasive surgical technique used for the correction of adult sagittal plane deformity. ACR is performed via a minimally invasive lateral transpsoas approach with anterior longitudinal ligament release and hyperlordotic cage placement. The objective of this study was to compare radiographic outcomes and complications in patients treated by ACR or Pedicle subtraction osteotomy (PSO). Patients who underwent ACR were matched with patients from a retrospective PSO dataset, by pelvic incidence, lumbar lordosis, and thoracic kyphosis. Inclusion criteria included pelvic incidence and lumbar lordosis mismatch > 10°, pelvic tilt > 25°, and/or C7 sagittal vertical axis >5 cm, and minimum 1-year follow-up. All (n= 17) patients who underwent ACR underwent second-stage open posterior instrumented fusion. There were no differences in baseline demographic or radiographic parameters. Both groups were found to have significant improvement from preoperative to final follow-up for lumbar lordosis, T1 spinopelvic inclination, and T1 pelvic angle. Pelvic tilt did not improve with PSO (31° to 28°) at final follow-up but did improve in ACR group (34° to 25°). No differences were identified at 3-month or final follow-up for lumbar lordosis (51° vs. 47°), pelvic tilt (25° vs. 28°), and T1 pelvic angle (23° vs. 24°). The group undergoing PSO achieved greater T1 spinopelvic inclination correction (8° vs. 1.9°). Patients who underwent ACR had significantly less estimated blood loss than patients who underwent PSO (1.6 vs. 3.6 L, respectively), but no difference in the overall major complication rates was found (35.3% vs. 41.2%, respectively). ACR achieved similar radiographic results as PSO in a matched cohort with significantly less estimated blood loss and similar overall complication rate.

The impact of spinopelvic morphology on the short-term outcome of pedicle subtraction osteotomy in 104 patients.

OBJECTIVE Pedicle subtraction osteotomy (PSO) is commonly performed for correction of spinal sagittal plane deformities. The PSO results in complex, multiple changes of the spinopelvic alignment. The influence of the variability of individual pelvic morphology has not been fully analyzed in previous outcome studies of sagittal imbalance. The aim of this study was to define radiological variables affecting the outcome after PSO in adult spinal deformities, with special emphasis on the variability of pelvic morphology. METHODS Clinical and radiographic outcomes were analyzed in a retrospective analysis of 104 patients who underwent a PSO at a single center. The radiographic variables studied were sagittal vertical axis (SVA), T1SPI (T-1 spinopelvic inclination), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). To control for the individual variation of pelvic morphology, the LL/PI, PT/PI, and SS/PI ratios were calculated. Clinical outcome was assessed using the visual analog scale for pain, Oswestry Disability Index, and EQ-5D preoperatively and at a minimum 1-year follow-up. Correlation coefficients were calculated between each individual radiographic variable and the outcome measures. The importance of LL mismatch to TK, reflecting the importance of a harmonious spine, was analyzed by comparing the outcome of patients with a TK+LL+PI ≤ 45° to those with a sum > 45°. RESULTS SVA and T1SPI demonstrated the strongest correlation with the clinical outcome scores (r = 0.4-0.5, p < 0.001). LL correlated weakly with the clinical outcome (r = 0.2-0.3, p < 0.003). Mismatch of LL to PI, however, did not correlate significantly with the outcome. Similarly, only weak and inconsistent correlation was observed between PT, SS, PT/PI, SS/PI, and functional outcome. Patients with a TK+LL+PI ≤ 45° had a significantly lower ODI score (33 vs 44) and a significantly higher EQ-5D score (0.64 vs 0.40) than patients with a sum > 45° (LL is a negative value). CONCLUSIONS PSO resulted in a substantial correction of sagittal imbalance and improved outcome in most patients in this study. Correction of the global sagittal balance appears to be a necessary precondition for a good outcome. A harmonious spine with a TK and an LL of similar magnitude seems to add to a positive outcome.