Biomechanical analysis of a trans-discal, multi-level stabilization screw (MLSS) at the upper instrumented vertebra (UIV) of long posterior thoracolumbar instrumentations.

PURPOSE: To evaluate proximal junctional biomechanics of a MLSS relative to traditional pedicle screw fixation at the proximal extent of T10-pelvis posterior instrumentation constructs (T10-p PSF). METHODS: A previously validated three-dimensional osseoligamentous spinopelvic finite element (FE) model was used to compare proximal junctional range-of-motion (ROM), vertebral body stresses, and discal biomechanics between two groups: (1) T10-p with a T10-11 MLSS ("T10-11 MLSS") and (2) T10-p with a traditional T10 pedicle screw ("Traditional T10-PS"). RESULTS: The T10-11 MLSS had a 5% decrease in T9 cortical bone stress compared to Traditional T10-PS. Conversely, the T10 and T11 bone stresses increased by 46% and 98%, respectively, with T10-11 MLSS compared to Traditional T10-PS. Annular stresses and intradiscal pressures (IDP) were similar at T9-T10 between constructs. At the T10-11 disc, T10-11 MLSS decreased annular stresses by 29% and IDP by 48% compared to Traditional T10-PS. Adjacent ROM (T8-9 & T9-10) were similar between T10-11 MLSS and Traditional T10-PS. T10-11 MLSS had 39% greater ROM at T10-11 and 23% less ROM at T11-12 compared to Traditional T10-PS. CONCLUSIONS: In this FE analysis, a T10-11 MLSS at the proximal extent of T10-pelvis posterior instrumentation resulted in increased T10 and T11 cortical bone stresses, decreased discal annular stress and IDP and increased ROM at T10-11, and no change in ROM at the adjacent level. Given the complex and multifactorial nature of proximal junctional kyphosis, these results require additional biomechanical and clinical evaluations to determine the clinical utility of MLSS on the proximal junctions of thoracolumbar posterior instrumented fusions.

Timelines for Return to Different Sports Types After Eight Cervical Spine Fractures in Recreational and Elite Athletes: A Survey of the Association for Collaborative Spine Research.

STUDY DESIGN: Prospective cross-sectional survey. OBJECTIVE: To identify timelines for when athletes may be considered safe to return to varying athletic activities after sustaining cervical spine fractures. BACKGROUND: While acute management and detection of cervical spine fractures have been areas of comprehensive investigation, insight into timelines for when athletes may return to different athletic activities after sustaining such fractures is limited. METHODS: A web-based survey was administered to members of the Association for Collaborative Spine Research that consisted of surgeon demographic information and questions asking when athletes (recreational vs elite) with one of 8 cervical fractures would be allowed to return to play noncontact, contact, and collision sports treated nonoperatively or operatively. The third part queried whether the decision to return to sports was influenced by the type of fixation or the presence of radiculopathy. RESULTS: Thirty-three responses were included for analysis. For all 8 cervical spine fractures treated nonoperatively and operatively, significantly longer times to return to sports for athletes playing contact or collision sports compared with recreational and elite athletes playing noncontact sports, respectively (P< 0.05), were felt to be more appropriate. Comparing collision sports with contact sports for recreational and elite athletes, similar times for return to sports for nearly all fractures treated nonoperatively or operatively were noted. In the setting of associated radiculopathy, the most common responses for safe return to play were "when only motor deficits resolve completely" and "when both motor and sensory deficits resolve completely." CONCLUSIONS: In this survey of spine surgeons from the Association for Collaborative Spine Research, reasonable timeframes for return to play for athletes with 8 different cervical spine fractures treated nonoperatively or operatively varied based on fracture subtype and level of sporting physicality.

Lumbar fusion surgery in the era of an aging society: analysis of a nationwide population cohort with minimum 8-year follow-up.

BACKGROUND CONTEXT: Fusions for lumbar spine diseases are widely performed and have a growing incidence, especially in elderly population. PURPOSE: The goal of this study was to assess national trends of lumbar spinal fusions and examine the risk for re-operations after a lumbar fusion with a focus on 'epidemiologic transition' relating to age. STUDY DESIGN/SETTING: The prospectively collected Korean Health Insurance Review and Assessment Service (HIRA) nationwide cohort database was retrospectively reviewed. PATIENT SAMPLE: The total 278,815 patients who underwent lumbar spinal fusions for degenerative spine diseases between 2010 and 2018 were reviewed and used to assess trends in operative incidence. The 37,050 patients who underwent lumbar fusions between 1/2010 and 12/2011 were enrolled to determine 8-year reoperation rates. OUTCOME MEASURES: The overall number of lumbar spinal fusions were analyzed for the national annual trend. Demographic data, reoperation rates, and confounding clinical factors were evaluated. METHODS: The overall number of lumbar spinal fusions was analyzed to determine the national annual trend of operative incidence. For the reoperation rate analysis, the primary outcome measured was the cumulative incidence of revision operations within a minimum 8-year follow-up period. Additional outcomes included comparative analyses of the reoperation rate with respect to age, sex, or other underlying comorbidities. RESULTS: Over time, elderly patients comprised a larger portion of the cohort (2010:24.2%; 2018:37.6%), while operations in younger patients decreased over time (2010:40.3%; 2018:27.0%). In the cohort of patients with a minimum 8-year follow-up (n=37,050), rates of reoperation peaked in patients aged 60-69 years (17.6 per 1000 person-years [HR 2.20 compared to <40years]) and decreased for more elderly patients (14.3 per 1000 person-years [HR 1.80 compared to <40years]). Age was the most significant risk factor for reoperation. Osteoporosis was also a risk factor for reoperation in post-menopausal females. CONCLUSIONS: Increasing incidence of lumbar fusions in elderly patients was seen however the risk of reoperation decreased in patients aged 70 or more. Lumbar fusion for elderly patients should not be hesitated in the decision-making process because of concerns about reoperation.

Comparative Analysis of Three Posterior-Only Surgical Techniques for Isthmic L5-S1 Spondylolisthesis.

OBJECTIVE: To compare adults with isthmic L5-S1 spondylolisthesis who were treated with three different surgical techniques: PS-only, TS, and transforaminal lumbar interbody fusion/posterior lumbar interbody fusion (TLIF/PLIF). METHODS: This is a retrospective analysis of adults with L5-S1 isthmic spondylolisthesis (grade ≥2) who underwent primary all-posterior operations with pedicle screws. Patients were excluded if they had <1 year follow-up, anterior approaches, and trans-sacral fibular grafts. Patient demographics and surgical, radiographic, and clinical data were compared between groups based on the method of anterior column support: none (PS-only), TS, and TLIF/PLIF. RESULTS: Sixty patients met inclusion criteria (male patients 21, female patients 39, average age 47 ± 15 years, PS-only 16; TS 20; TLIF/PLIF 24). TS patients more commonly had high-grade slips and markedly greater slip percentage, lumbosacral kyphosis, and pelvic incidence. The three groups were similar for smoking status, visual analog scores/Oswestry Disability Index scores (VAS/ODI), surgical data, and average follow-up (40.1 ± 31.2 months). All groups had similarly notable improvements in Meyerding grade and lumbosacral angle. Slip reduction percentage was similar between groups. While there was a markedly higher overall complication rate for PS-only constructs, all groups had similarly notable improvements in ODI and VAS back scores. CONCLUSIONS: All-posterior techniques for L5-S1 isthmic spondylolisthesis resulted in excellent improvement in preoperative symptoms and HRQoL scores and similar radiographic alignment. Trans-sacral screws were more commonly used for high-grade slips. The use of anterior column support resulted in fewer overall complications than posterior-only instrumentation.

Coronal Alignment in Adult Spine Surgery.

Coronal realignment is an important goal in adult spine surgery that has been overshadowed by emphasis on the sagittal plane. As coronal malalignment drives considerable functional disability, a fundamental understanding of its clinical and radiographic evaluation and surgical techniques to prevent its development is of utmost importance. In this study, we review etiologies of coronal malalignment and their radiographic and clinical assessments, risk factors for and functional implications of postoperative coronal malalignment, and surgical strategies to optimize appropriate coronal realignment in adult spine surgery.

Costs of revision operations for distal junctional kyphosis following thoracic posterior spinal fusion for adolescent idiopathic scoliosis.

PURPOSE: To assess direct costs and risks associated with revision operations for distal junctional kyphosis/failure (DJK) following thoracic posterior spinal instrumented fusions (TPSF) for adolescent idiopathic scoliosis (AIS). METHODS: Children who underwent TPSF for AIS by a single surgeon (2014-2020) were reviewed. Inclusion criteria were minimum follow-up of 2 years, thoracolumbar posterior instrumented fusion with a lower instrumented vertebra (LIV) cranial to L2. Patients who developed DJK requiring revision operations were identified and compared with those who did not develop DJK. RESULTS: Seventy-nine children were included for analysis. Of these, 6.3% developed DJK. Average time to revision was 20.8 ± 16.2 months. Comparing index operations, children who developed DJK had significantly greater BMIs, significantly lower thoracic kyphosis postoperatively, greater post-operative lumbar Cobb angles, and significantly more LIVs cranial to the sagittal stable vertebrae (SSV), despite having statistically similar pre-operative coronal and sagittal alignment parameters and operative details compared with non-DJK patients. Revision operations for DJK, when compared with index operations, involved significantly fewer levels, longer operative times, greater blood loss, and longer hospital lengths of stay. These factors resulted in significantly greater direct costs for revision operations for DJK ($76,883 v. $46,595; p < 0.01). CONCLUSIONS: In this single-center experience, risk factors for development of DJK were greater BMI, lower post-operative thoracic kyphosis, and LIV cranial to SSV. As revision operations for DJK were significantly more costly than index operations, all efforts should be aimed at strategies to prevent DJK in the AIS population.

Resection of a Recurrent Lumbar Chordoma With Intradural Extension and Complex Dural Repair: 2-Dimensional Operative Video.

Chordomas are derived from embryonic notochord remnants and comprise 1%-4% of all bone tumors.1 Nearly all chordomas arise in the axial skeleton, with 50% in the sacrococcygeal region, 35% in the skull base and 15% within mobile spine vertebrae.1,2 Regional recurrence after en bloc surgery is common and 30%-40% of patients develop metastatic disease.3-6 In this operative video, we present a 41-year old man who previously underwent en bloc lateral L1 corpectomy and received high-dose hybrid photon and proton radiation therapy for treatment of his L1 chordoma. On surveillance imaging, 2 years post op MRI revealed recurrence of the chordoma, now extending to the L2-3 epidural space. Further radiation alone was considered but was not performed due to lack of separation between the tumor and neural elements, thus increasing the risk of radiation-induced neurological injury. Combination revision surgical resection with subsequent boost radiation therapy was pursued instead. The technical nuances to achieve complex ventral and dorsal dural repair after removal of a transdural lumbar chordoma are shown in detail. Postoperatively, the patient had no new neurological deficits. At 13 months postoperatively, he reports no new pain, can ambulate without assistance, and completed 33 treatments of radiation therapy with proton beam. The patient consented to the procedure and to the publication of his image.

Understanding the etiopathogenesis of lumbar intervertebral disc herniation: From clinical evidence to basic scientific research.

Lumbar intervertebral disc herniation, as a leading cause of low back pain, productivity loss, and disability, is a common musculoskeletal disorder that results in significant socioeconomic burdens. Despite extensive clinical and basic scientific research efforts, herniation etiopathogenesis, particularly its initiation and progression, is not well understood. Understanding herniation etiopathogenesis is essential for developing effective preventive measures and therapeutic interventions. Thus, this review seeks to provide a thorough overview of the advances in herniation-oriented research, with a discussion on ongoing challenges and potential future directions for clinical, translational, and basic scientific investigations to facilitate innovative interdisciplinary research aimed at understanding herniation etiopathogenesis. Specifically, risk factors for herniation are identified and summarized, including familial predisposition, obesity, diabetes mellitus, smoking tobacco, selected cardiovascular diseases, disc degeneration, and occupational risks. Basic scientific experimental and computational research that aims to understand the link between excessive mechanical load, catabolic tissue remodeling due to inflammation or insufficient nutrient supply, and herniation, are also reviewed. Potential future directions to address the current challenges in herniation-oriented research are explored by combining known progressive development in existing research techniques with ongoing technological advances. More research on the relationship between occupational risk factors and herniation, as well as the relationship between degeneration and herniation, is needed to develop preventive measures for working-age individuals. Notably, researchers should explore using or modifying existing degeneration animal models to study herniation etiopathogenesis, as such models may allow for a better understanding of how to prevent mild-to-moderately degenerated discs from herniating.

Trans-Sternal Multilevel Corpectomy for Cervicothoracic Renal Cell Metastasis: 2-Dimensional Operative Video.

The operative management of pathological fractures at the cervicothoracic junction is a surgical challenge. Here, we present the case of a 48-year-old male patient presenting with 2 months of progressive left upper extremity weakness as well as back and bilateral arm pain (Karnofsky Performance Status 60%) who was found to have pathological fractures from C7, T1, and T2 due to metastatic renal cell carcinoma. Renal cell carcinoma is known to metastasize to bone and cause cord compression.1 Given the extensive metastasis with this highly vascular tumor, endovascular embolization was performed preoperatively to minimize intraoperative blood loss.2 Surgical management consisted of a two-stage procedure. Posterior spinal fusion from C2-T7 with C7-T2 decompression was performed during stage 1. Stage 2 consisted of a trans-sternal approach for C7, T1, and T2 corpectomy for cord decompression and placement of a cage and plate for anterior column support.3 Although prior surgeons have suggested to access upper thoracic pathology through an interaortocaval window, in this case we demonstrate a trans-sternal approach to C6-T3 that starts superior to the innominate vein and aortic arch and angles inferiorly dorsal to these vascular structures.4 When planning for a manubriotomy/trans-sternal approach, access to T1/T2 remains the most decisive factor and is most successful with a sternotomy.5 At 12-month follow-up, the patient demonstrated improvement in his left upper extremity strength and overall functional status (3/5 strength in hand grip and interossei with 5/5 in all remaining motor groups; Karnofsky Performance Status 80%). The patient consented to participate in the surgery and surgical video.

Anterior lumbar interbody fusion versus transforaminal lumbar interbody fusion for correction of lumbosacral fractional curves in adult (thoraco)lumbar scoliosis: A systematic review.

Background: Anterior lumbar interbody fusion (ALIF) or transforaminal lumbar interbody fusion (TLIF) may be used to correct the lumbosacral fractional curve (LsFC) in de novo adult (thoraco) lumbar scoliosis. Yet, the relative benefits of ALIF and TLIF for LsFC correction remain largely undetermined. Purpose: To compare the currently available data comparing radiographic correction of the LsFC provided by ALIF and TLIF of LsFC in adult (thoraco)lumbar scoliosis. Methods: A systematic review was performed on original articles discussing fractional curve correction of lumbosacral spinal deformity (using search criteria: "lumbar" and "fractional curve"). Articles which discussed TLIF or ALIF for LsFC correction were presented and radiographic results for TLIF and ALIF were compared. Results: Thirty-one articles were returned in the original search criteria, with 7 articles included in the systematic review criteria. All 7 articles presented radiographic results using TLIF for LsFC correction. Three of these articles also discussed results for patients whose LsFC were treated with ALIFs; 2 articles directly compared TLIF and ALIF for LsFC correction. Level III and level IV evidence indicated ALIF as advantageous for reducing the coronal Cobb angle of the LsFC. There were mixed results on relative efficacy of ALIF and TLIF in the LsFC for restoration of adequate global coronal alignment. Conclusions: Limited level III and IV evidence suggests ALIF as advantageous for reducing the coronal Cobb angle of the LsFC in de novo adult (thoraco) lumbar scoliosis. Relative efficacy of ALIF and TLIF in the LsFC for restoration of global coronal alignment may be dictated by several factors, including directionality and magnitude of preoperative coronal deformity. Given the limited and low-quality evidence, additional research is warranted to determine the ideal interbody support strategies to address the LsFC in adult (thoraco) lumbar scoliosis.

Biomechanical evaluation of multi-rod constructs to stabilize an S1 pedicle subtraction osteotomy (PSO): a finite element analysis.

PURPOSE: To develop and validate a finite element (FE) model of a sacral pedicle subtraction osteotomy (S1-PSO) and to compare biomechanical properties of various multi-rod configurations to stabilize S1-PSOs. METHODS: A previously validated FE spinopelvic model was used to develop a 30° PSO at the sacrum. Five multi-rod techniques spanning the S1-PSO were made using 4 iliac screws and a variety of primary rods (PR) and accessory rods (AR; lateral: Lat-AR or medial: Med-AR). All constructs, except one, utilized a horizontal rod (HR) connecting the iliac bolts to which PRs and Med-ARs were connected. Lat-ARs were connected to proximal iliac bolts. The simulation was performed in two steps with the acetabula fixed. For each model, PSO ROM and maximum stress on the PRs, ARs, and HRs were recorded and compared. The maximum stress on the L5-S1 disc and the PSO forces were captured and compared. RESULTS: Highest PSO ROMs were observed for 4-Rods (HR + 2 Med-AR). Constructs consisting of 5-Rods (HR + 2 Lat-ARs + 1 Med-AR) and 6-Rods (HR + 2 Lat-AR + 2 Med-AR) had the lowest PSO ROM. The least stress on the primary rods was seen with 6-Rods, followed by 5-Rods and 4-Rods (HR + 2 Lat-ARs). Lowest PSO forces and lowest L5-S1 disc stresses were observed for 4-Rod (Lat-AR), 5-Rod, and 6-Rod constructs, while 4-Rods (HR + Med-AR) had the highest. CONCLUSION: In this first FE analysis of an S1-PSO, the 4-Rod construct (HR + Med-AR) created the least rigid environment and highest PSO forces anteriorly. While 5- and 6-Rods created the stiffest constructs and lowest stresses on the primary rods, it also jeopardized load transfer to the anterior column, which may not be favorable for healing anteriorly. A balance between the construct's rigidity and anterior load sharing is essential.

Bilateral dual iliac screw pelvic fixation for adult spinal deformity: a case report of a superior gluteal artery pseudoaneurysm secondary to aberrant iliac screw trajectory.

PURPOSE: To present a case of a pseudoaneurysm of a branch of the left superior gluteal artery (SGA) secondary to lateral wall perforation from an iliac screw and its subsequent evaluation and management. METHODS: Case report. RESULTS: A 67-year-old female with a history of degenerative flatback and scoliosis and pathological fractures of T12 and L1 secondary to osteodisciitis underwent a single0stage L5-S1 ALIF and T9-pelvis posterior instrumented fusion with bilateral dual iliac screw fixation, revision T11-S1 decompression, and T12 and L1 irrigation and debridement and partial corpectomies. During the operation, non-pulsatile bleeding was encountered after creating an initial trajectory for the more proximal of the two left iliac screws. While the initial post-operative course was benign, the patient was readmitted for hypotension and anemia. Computed tomography of the abdomen/pelvis demonstrated a pseudoaneurysm (2.3 cm × 2.1 cm × 2.3 cm) of a branch of the left SGA. Diagnostic angiogram confirmed a pseudoaneurysm off of one of the branches of the left SGA. Endovascular embolization using multiple coils resulted in a complete cessation of blood flow in the pseudoaneurysm. At 2 years follow-up, no symptoms suggestive of recurrence of the pseudoaneurysm were reported. CONCLUSIONS: A pseudoaneurysm of a branch of the left superior gluteal artery as a result of lateral wall perforation from an aberrantly placed iliac screw during an adult spinal deformity operation involving dual screw pelvic fixation is reported. Prompt recognition, multidisciplinary collaboration, and appropriate intervention were key in achieving a successful outcome and preventing further morbidity.

Odontoid fractures above C2 to pelvis posterior instrumented fusions: a single center's 11-year experience.

PURPOSE: To define the prevalence, characteristics, and treatment approach for proximal junction failure secondary to odontoid fractures in patients with prior C2-pelvis posterior instrumented fusions (PSF). METHODS: A single institution's database was queried for multi-level fusions (6+ levels), including a cervical component. Posterior instrumentation from C2-pelvis and minimum 6-month follow-up was inclusion criteria. Patients who sustained dens fractures were identified; each fracture was subdivided based on Anderson & D'Alonzo and Grauer's classifications. Comparisons between the groups were performed using Chi-square and T tests. RESULTS: 80 patients (71.3% female; average age 68.1 ± 8.1 years; 45.0% osteoporosis) were included. Average follow-up was 59.8 ± 42.7 months. Six patients (7.5%) suffered an odontoid fracture post-operatively. Cause of fracture in all patients was a mechanical fall. Average time to fracture was 23 ± 23.1 months. Average follow-up after initiation of fracture management was 5.84 ± 4 years (minimum 1 year). Three patients sustained type IIA fractures one of which had a concomitant unilateral C2 pars fracture. Three patients sustained comminuted type III fractures with concomitant unilateral C2 pars fractures. Initial treatment included operative care in 2 patients, and an attempt at non-operative care in 4. Non-operative care failed in 75% of patients who ultimately required revision with proximal extension. All patients with a concomitant pars fracture had failure of non-operative care. Patients with an intact pars were more stable, but 50% required revision for pain. CONCLUSIONS: In this 11-year experience at a single institution, the prevalence of odontoid fractures above a C2-pelvis PSF was 7.5%. Fracture morphology varied, but 50% were complex, comminuted C2 body fractures with concomitant pars fractures. While nonoperative management may be suitable for type II fractures with simple patterns, more complex and unstable fractures likely benefit from upfront surgical intervention to prevent fracture displacement and neural compression. As all fractures occurred secondary to a mechanical fall, inpatient and community measures aimed to minimize risk and prevent mechanical falls would be beneficial in this high-risk group.

Abdominal lymphocele following multi-level anterior lumbar interbody fusion (ALIF) managed with a laparoscopic peritoneal window: case report and review of the literature.

PURPOSE: Lymphocele formation following anterior lumbar interbody fusion (ALIF) is not common, but it can pose diagnostic and treatment challenges. The purpose of this case is to report for the first time the treatment of a postoperative lymphocele following a multi-level ALIF using a peritoneal window made through a minimally invasive laparoscopic approach. METHODS: Case report. RESULTS: A 74-year-old male with a history of prostatectomy and pelvic radiation underwent a staged L3-S1 ALIF (left paramedian approach) and T10-pelvis posterior instrumented with L1-5 decompression/posterior column osteotomies for degenerative scoliosis and neurogenic claudication. Three weeks after surgery, swelling of the left abdomen and entire left leg was reported. Computed tomography of the abdomen/pelvis demonstrated a large (19.2 × 12.0 × 15.4 cm) retroperitoneal fluid collection with compression of the left ureter and left common iliac vein. Fluid analysis (80% lymphocytes) was consistent with a lymphocele. Percutaneous drainage for 4 days was ineffective at clearing the lymphocele. For more definitive management, the patient underwent an uncomplicated laparoscopic creation of a peritoneal window to allow passive drainage of lymphatic fluid into the abdomen. Three years after surgery, he had no back or leg pain, had achieved spinal union, and had no abdominal swelling or left leg swelling. Advanced imaging also confirmed resolution of the lymphocele. CONCLUSIONS: In this case report, creation of a peritoneal window minimally invasively via a laparoscope allowing passive drainage of lymphatic fluid into the abdomen was safe and effective for management of an abdominal lymphocele following a multi-level ALIF.

Proximal Junctional Kyphosis and Failure: Strategies for Prevention.

Proximal junctional kyphosis (PJK) and proximal junctional failure/fractures (PJF) are common complications following long-segment posterior instrumented fusions for adult spinal deformity. As progression to PJF involves clinical consequences for patients and requires costly revisions that may undermine the utility of surgery and are ultimately unsustainable for health care systems, preventative strategies to minimize the occurrence of PJF are of tremendous importance. In this article, the authors present a detailed outline of PJK and PJF with a focus on surgical strategies aimed at preventing their occurrence..

Activity and sports resumption after long segment fusions to the pelvis for adult spinal deformity: survey results of AO Spine members.

PURPOSE: To assess recommendations for when adult spinal deformity (ASD) patients may return to athletic activities after surgery. METHODS: A web-based survey was administered to members of AO Spine. The survey consisted of surgeon demographic information and questions asking when a patient undergoing a long thoracolumbar fusion (> 5 levels) with pelvic fixation for ASD would be allowed to resume unrestricted range of motion (ROM), non-contact sports, and contact sports postoperatively. Ordinal logistic regression was used to determine predictors for time to resume each activity. RESULTS: One hundred twenty four members' responses were included for analysis. The majority of respondents would allow unrestricted ROM within 3 months postop (< 3 months: 81% vs > 3 months: 19%]. For when to return to non-contact sports, the most common responses were "2-3 months" (26.6%), "3-4 months" (26.6%), and "6-12 months" (18.5%). For when to return to contact sports, the majority advised > 4 months postop [> 4 months: "4-6 months" (19.2%), "6-12 months" (28.0%), " > 12 months" (28.8%) versus < 4 months: "1-2 months" (4.0%), "2-3 months" (1.6%), "3-4 months" (8.8%)]. 8.8% responded they would "never" allow resumption of contact sports. CONCLUSION: There was significant variation between surgeons' recommendations for resumption of unrestricted range of motion and sports following long fusion with pelvic fixation for ASD. An evidence-based approach to activity recommendations will require information on outcomes and complications.

Navigated Hybrid Open/Muscle-sparing Approach to 2-level Cement Augmentation of the UIV and UIV+1 for Prevention of Proximal Junctional Failure: Supplemental Manuscript to Operative Video.

STUDY DESIGN: Operative video and supplemental manuscript. OBJECTIVE: To present a cement augmentation technique of the upper instrumented vertebra (UIV) and UIV+1 for prevention of proximal junctional fractures (PJFs) in multi-level thoracolumbar posterior instrumented fusions. SUMMARY OF BACKGROUND DATA: PJFs are unfortunately a common occurrence after multi-level thoracolumbar instrumented fusions to the pelvis for adult spinal deformity that can result in significant functional disability and often require costly revision operations. As such, their prevention is key. METHODS: A surgical video illustrates the nuances of a 2-level cement augmentation technique, consisting of an open vertebroplasty of the UIV through fenestrated screws and a muscle-sparing kyphoplasty of the UIV+1. RESULTS: Utility of performing an open vertebroplasty of the UIV through fenestrated screws and muscle-sparing kyphoplasty of the UIV+1 lies in its ability to minimize soft-tissue disruption at the adjacent segment while providing additional structural support to the anterior column at this high-risk zone. CONCLUSIONS: Cement augmentation of the UIV and UIV+1 consisting of a hybrid open vertebroplasty and muscle-sparing kyphoplasty can be an effective strategy to decrease the incidence of PJF after multi-level posterior thoracolumbar instrumented fusions to the pelvis for adult spinal deformity.

Lumbar Pedicle Subtraction Osteotomy (PSO): A Novel Surgical Technique for Correction of Sagittal and Coronal Imbalance Using Laterally Based Satellite Rods.

STUDY DESIGN: Operative video and supplemental manuscript. OBJECTIVE: To present a novel step-by-step approach to performing a lumbar pedicle subtraction osteotomy (PSO) using laterally based satellite rods. SUMMARY OF BACKGROUND DATA: Multi-rod constructs have demonstrated paramount for decreasing rates of pseudarthrosis after PSOs. Multi-rods constructs can be achieved using either "satellite" rods (rods not connected to the primary rods) and/or "accessory rods" (rods connected to the primary rods). METHODS: A step-by-step approach to performing a lumbar PSO using a laterally based satellite rod configuration is provided through a case example and surgical technique video. RESULTS: Lateral satellite rods can be particularly useful from a surgical perspective, as they provide temporary stabilization while the PSO is being performed, facilitate closure of the osteotomy site (symmetric and/or asymmetric), and serve as the final fixation rods across the PSO without needing to be exchanged. CONCLUSIONS: Use of laterally based satellite rods is a useful technique for lumbar PSOs, as they provide temporary stabilization while the PSO is being performed, facilitate closure of the osteotomy site, and serve as the final fixation rods across the PSO without needing to be exchanged.