An In Vitro Biomechanical Analysis of Contralateral Sacroiliac Joint Motion Following Unilateral Sacroiliac Stabilization with and without Lumbosacral Fixation.

STUDY DESIGN: Cadaveric biomechanics study. PURPOSE: This study investigated the effects of unilateral sacroiliac joint (SIJ) fixation for fusion with/without L5-S1 fixation on contralateral SIJ range of motion (ROM). OVERVIEW OF LITERATURE: SIJ fusion raises concerns that unilateral SIJ stabilization for fusion may increase contralateral SIJ mobility, leading to accelerated SIJ degeneration. Also, prior lumbosacral fixation may lead to accelerated SIJ degeneration, due to adjacent level effects. SIJ fixation biomechanics have been evaluated, showing a reduced-ROM, but SIJ fixation effects on contralateral nonfixated SIJ remain unknown. METHODS: Seven human lumbopelvic spines were used, each affixed to six-degrees-of-freedom testing apparatus; 8.5-Nm pure unconstrained bending moments applied in flexion-extension, lateral bending, and axial rotation. The ROM of left and right SIJ was measured using a motion analysis system. Each specimen tested as (1) intact, (2) injury (left), (3) L5-S1 fixation, (4) unilateral stabilization (left), (5) unilateral stabilization+L5-S1 fixation, (6) bilateral stabilization, and (7) bilateral stabilization+L5-S1 fixation. Both left-sided iliosacral and posterior ligaments were cut for injury condition to model SIJ instability before surgery. RESULTS: There were no statistical differences between fixated and contralateral nonfixated SIJ ROM following unilateral stabilization with/without L5-S1 fixation for all loading directions (p>0.930). Injured condition and L5-S1 fixation provided the largest motion increases across both joints; no significant differences were recorded between SIJs in any loading direction (p>0.850). Unilateral and bilateral stabilization with/without L5-S1 fixation reduced ROM compared with the injured condition for both SIJs, with bilateral stabilization providing maximum stability. CONCLUSIONS: In the cadaveric model, unilateral SIJ stabilization with/without lumbosacral fixation did not lead to significant contralateral SIJ hypermobility; long-term changes and in vivo response may differ.

Long-term follow-up of the radiofrequency ablation of benign thyroid nodules: the value of additional treatment.

PURPOSE: This study aimed to evaluate the efficacy of additional radiofrequency ablation (RFA) treatment for benign thyroid nodules. METHODS: Electronic medical records at a single institution from September 2008 to August 2016 were searched, and consecutive patients treated with RFA due to benign thyroid nodules with cosmetic or symptomatic problems were enrolled. All patients were followed up for at least 30 months. The nodules were divided into three groups: group 1 included nodules that met the criteria for additional treatment and underwent additional treatment, group 2 included nodules that met the criteria but did not undergo additional treatment, and group 3 included nodules that did not meet the criteria. The ablation results were compared among the three groups in terms of the initial ablation ratio (IAR) and volume reduction ratio (VRR). RESULTS: Ninety nodules from 88 patients were included in the study. At the last follow-up, group 1 showed a significantly smaller nodule volume and larger VRR (2.5 mL and 84.6%, respectively) than group 2 (8.1 mL and 39.8%, respectively, P<0.001), but did not present a significant difference from group 3 (0.9 mL, P=0.347, and 92.8%, P=0.238). The IAR was significantly higher in group 3 (94.5%) than in the other two groups (group 1, 81.1%; group 2, 82.8%; P<0.001). CONCLUSION: Multiple treatment sessions achieve greater VRR. Therefore, additional treatment could be considered for patients who meet the corresponding criteria.

Geometric analysis of pedicle subtraction osteotomy (PSO) for Kyphosis correction: anterior lengthening may occur at the osteotomized body as well as at the discs above and below.

OBJECTIVE: To validate the authors kyphosis correction formula for pedicle subtraction osteotomy (PSO) cases. Additionally, to use the formula to evaluate the safety of PSO by determining if there is anterior lengthening. METHODS: Twenty-two patients with primarily kyphosis corrected by PSO and with clear landmarks on preoperative and postoperative x-rays were selected. Several anatomical lines and angle measurements were utilized as depicted previously in the Vertebral Column Resection formula (see below). Two approximations were calculated: the geometric approximation (G) = (tanG°*2 + 1)*15° and the rough approximation (R) which is about the same amount of actual shortening (x), if parallel length (y) ≥ 40; twice of x, if y < 40. For each patient, the change of segmental kyphosis angle (K°) was measured and compared with G° and R°, and the correlation between each value was analyzed. RESULTS: The absolute Mean ± SE for K - G and K - R was 2.33° ± 0.34 and 6.09° ± 0.58, respectively. K - G is < 3° (p = 0.03). K - R is < 8° (p = 0.001). In other words, K was close to G and R and thus can be predicted by these approximations. Average posterior shortening, anterior shortening, and kyphosis correction at each level were 20.8 ± 2.0 mm, - 3.64 ± 1.5 mm (which equates to anterior lengthening), and 31.05° ± 2.0, respectively. Anterior lengthening occurred in 13 cases (in 4 cases, both at the body as well as at the disc above and below.) The correlation between posterior and anterior shortening was 0.03 (p = 0.88). There were 3 cage insertion cases: 1 had anterior lengthening, while 2 had anterior shortening even with the cage. CONCLUSION: This study validated the geometric and rough approximations originally used in PVCR patients, for PSO patients. Additionally, this study found that anterior lengthening may occur in PSOs usually at the discs, but occasionally at the osteotomized body.

Acute Cholecystitis: An Emerging Complication in Spinal Cord Injury Patients in the United States.

BACKGROUND: Spinal cord injury (SCI) is a significant medical condition associated with various secondary complications, including cholelithiasis. Cholelithiasis can cause biliary duct obstruction and result in acute cholecystitis. The development of acute cholecystitis in SCI patients has been well studied in the Taiwanese population, showing an increased risk of acute cholecystitis in patients with SCI. The development of cholecystitis has not been well studied in the United States. MATERIALS AND METHODS: A retrospective review was performed on 3,939 propensity score-matched patients aged 18 to 85 years who had SCI/surgery from 2000 to 2019. Patients were divided based on the development of postoperative complications, specifically cholecystitis with cholecystectomy. RESULTS: SCI consisted of quadriplegia (42%), paraplegia (53%), unspecified lesion of cervical spinal cord (3%), and thoracic spinal cord (2%). All groups were comparable regarding age, gender, body mass index, smoking status, and Charlson comorbidity Index. The incidence of acute cholecystitis with subsequent cholecystectomy among patients with SCI was 43.0 per 10,000 person-years (95% confidence interval: 41.51-44.49). Median follow-up was 36 months. The development of cholecystitis was comparable among females (54.5%) and males (45.5%), and among African Americans (52.5%) and Caucasians (47.5%). CONCLUSION: There is an association between SCI and development of acute cholecystitis among U.S. PATIENTS: As SCI patients do not present with the classic signs of biliary colic, risk assessment for the development of acute cholecystitis will guide patient management and allow neurosurgeons to weigh the risks and benefits of prophylactic treatment for gallbladder complications.

The Feasibility of Translaminar Screws in the Subaxial Cervical Spine: Computed Tomography and Cadaveric Validation.

BACKGROUND: The use of translaminar screws may serve as a viable salvage method for complicated cases. To our understanding, the study of the feasibility of translaminar screw insertion in the actual entire subaxial cervical spine has not been carried out yet. The purpose of this study was to report the feasibility of translaminar screw insertion in the entire subaxial cervical spine. METHODS: Eighteen cadaveric spines were harvested from C3 to C7 and 1-mm computed tomography (CT) scans and three-dimensional reconstructions were created to exclude any bony anomaly. Thirty anatomically intact segments were collected (C3, 2; C4, 3; C5, 3; C6, 8; and C7, 14), and randomly arranged. Twenty-one segments were physically separated at each vertebral level (group S), while 9 segments were not separated from the vertebral column and left in situ (group N-S). CT measurement of lamina thickness was done for both group S and group N-S, and manual measurement of various length and angle was done for group S only. Using the trajectory proposed by the previous studies, translaminar screws were placed at each level. Screw diameter was the same or 0.5 mm larger than the proposed diameter based on CT measurement. Post-insertion CT was performed. Cortical breakage was checked either visually or by CT. RESULTS: When 1° and 2° screws of the same size were used, medial cortex breakage was found 13% and 33% of the time, respectively. C7 was relatively safer than the other levels. With larger-sized screws, medial cortex breakage was found in 47% and 46% of 1° and 2° screws, respectively. There were no facet injuries due to the screws in group N-S. CONCLUSIONS: Translaminar screw insertion in the subaxial cervical spine is feasible only when the lamina is thick enough to avoid any breakage that could lead to further complications. The authors do not recommend inserting translaminar screws in the subaxial cervical spine except in some salvage cases in the presence of a thick lamina.

Modic Change: An Emerging Complication in the Aging Population.

STUDY DESIGN: This was a literature review. OBJECTIVE: The objective of this study was to review the pathogenesis, prevalence, clinical associations, diagnostic modalities, and treatment options for patients with lower back pain (LBP) associated with Modic change (MC). SUMMARY OF BACKGROUND DATA: Vertebral body endplates are located between the intervertebral disk and adjacent vertebral body. Despite their crucial roles in nutrition and biomechanical stability, vertebral endplates are extremely susceptible to mechanical failure. Studies examining the events leading to disk degeneration have shown that failure often begins at the endplates. Endplate degeneration with subchondral bone marrow changes were originally noticed on magnetic resonance imaging. These magnetic resonance imaging signal changes were classified as MC. METHODS: A literature review was conducted on the history, etiology, risk factors, diagnostic modalities, and treatment of LBP with MC. RESULTS: Type 1 MC refers to the presence of increased vascularization and bone marrow edema within the vertebral body. Type 2 MC involves fatty marrow replacement within the vertebral body. Type 3 MC reflects subchondral bone sclerosis. Despite the original classification, research has supported the notion that MCs possess a transitional nature. Furthermore, type 1 MCs have been strongly associated with inflammation and severe LBP, while types 2 and 3 tend to be more stable and demonstrate less refractory pain. With a strong association to LBP, understanding the etiology of MC is crucial to optimal treatment planning. Various etiologic theories have been proposed including autoimmunity, mechanics, infection, and genetic factors. CONCLUSIONS: With the aging nature of the population, MC has emerged as an extremely prevalent issue. Research into the pathogenesis of MC is important for planning preventative and therapeutic strategies. Such strategies may include rehabilitation, surgical fixation, stabilization, steroid or cement injection, or antibiotics. Improved diagnostic methods in clinical practice are thus critical to properly identify patients suffering from MC, plan early intervention, and hasten return to functioning.

Investigational Therapies for Gunshot Wounds to the Spine: A Narrative Review.

STUDY DESIGN: This was a narrative review. OBJECTIVE: The objective of this study was to review the standards of care and triage protocol for gunshot wounds to the spine, highlighting innovative future treatment options that may be implemented in patients with spinal cord injury (SCI). SUMMARY OF BACKGROUND DATA: With the increased availability of firearms among the United States population, gunshot wounds to the spine are becoming a clinically relevant and devastating issue. Such injuries result in severe and diverse complications. SCIs due to gunshot wounds are the leading cause of morbidity and mortality, as they often result in complete or incomplete paraplegia. Current standards of care focus on preventing further damage rather than total cure or treatment of SCI. METHODS: A literature review was performed on the standards of care, triage protocol, associated conditions, current therapeutic options, and innovative treatment options for patients with gunshot wounds to the spine. RESULTS: The general standards of care for spinal gunshot wounds involve maintaining or renewal of mechanical spinal steadiness and neurological activity while limiting complications of treatment. Current treatment options include management of mean arterial pressure goals, drug therapies consisting of antibiotics, and surgical approaches. With recent innovations in molecular biology and cell transplantation, potentially new and promising treatment options for patients with SCI exist. These options include cell transplantation therapies, platelet-rich plasma administration, exosomal treatments, and mitochondrial-targeted therapeutics. Stem cell transplantation is promising, as several clinical studies have been completed. However, loss-to-follow-up, lack of long-term evaluation, and questionable randomization has limited the use of stem cells in the standard of care practice. Although not studied on human models to a gunshot wound, exosomal and mitochondrial-based treatment options have been studied both in vitro and in animal models with SCI. CONCLUSION: Newly emerging molecular and cellular therapy modalities for SCI contribute to the recovery process and may be utilized in conjunction with the current modalities for better outcomes.

Proximal Junctional Kyphosis in Adult Spinal Deformity: Definition, Classification, Risk Factors, and Prevention Strategies.

Proximal junctional problems are among the potential complications of surgery for adult spinal deformity (ASD) and are associated with higher morbidity and increased rates of revision surgery. The diverse manifestations of proximal junctional problems range from proximal junctional kyphosis (PJK) to proximal junctional failure (PJF). Although there is no universally accepted definition for PJK, the most common is a proximal junctional angle greater than 10° that is at least 10° greater than the preoperative measurement. PJF represents a progression from PJK and is characterized by pain, gait disturbances, and neurological deficits. The risk factors for PJK can be classified according to patient-related, radiological, and surgical factors. Based on an understanding of the modifiable factors that contribute to reducing the risk of PJK, prevention strategies are critical for patients with ASD.

Crossing the Cervico-Thoracic Junction in Long Posterior Cervical Fusions Reduces Caudal Adjacent Segment Pathology.

STUDY DESIGN: Retrospective case control. OBJECTIVES: The purpose of this study is to compare clinical outcomes and rates of symptomatic caudal adjacent segment pathology (ASP) in posterior cervical fusions (PCF) constructs with end-instrumented vertebrae in the cervical spine (EIV-C) to PCF constructs that end in the proximal thoracic spine (EIV-T). METHODS: Retrospective review of 1714 consecutive cervical spinal fusion cases was done. Two groups were identified: 36 cervical end-instrumented vertebra patients (age56 ± 10 yrs) and 53 thoracic EIV patients (age 57 ± 9 yrs). Symptomatic ASP was defined as revision surgery or nerve root injection (or recommended surgery or injection) at the adjacent levels. RESULTS: EIV-C patients had a significantly higher rate of caudal-level symptomatic ASP requiring intervention compared with EIV-T patients (39% vs 15%, p = 0.01). The development of caudal-level ASP was highest at C7 (41%), followed by C6 (40%). The overall complication rate and surgical revision rates, however, were similar between the groups. Neck Disability Index outcomes at 2 years postop were significantly better in the EIV-T group (24.5 vs. 34.0, p = 0.05). CONCLUSIONS: Long PCF that cross the C-T junction have superior clinical outcomes and reduced rates of caudal breakdown, at the expense of longer fusions and higher EBL, with no increase in the rate of complications. Crossing the C-T junction affords protection of the caudal adjacent levels without adding significant operative time or morbidity.

Racial Differences in Iliac Crest Cancellous Bone Composition: Implications for Preoperative Planning in Spinal Fusion Procedures.

STUDY DESIGN: This was a retrospective cohort study. OBJECTIVE: The objective of this study was to determine whether race, specifically American white and American black, correlates with the ratio of cancellous to total bone at the iliac crest. SUMMARY OF BACKGROUND DATA: Studies have demonstrated higher proximal femur bone density in American blacks than American whites. However, whether differences occur at the iliac crest, a common site for autologous graft material in spinal fusion surgery, is not well studied. Understanding such differences could aid orthopedic surgeon decision-making regarding graft options. MATERIALS AND METHODS: A retrospective review was performed on 133 sequential patients ages 18-75 who underwent computed tomography scan of the pelvis, at a single academic medical center from January 1, 2014, to January 1, 2016. The cohort included 46 American white (21 females, 25 males) and 87 American black participants (40 females, 37 males), an average age of 51.8 years. Groups were matched regarding age, sex, body mass index, and Charlson Comorbidity Score. Measurements of cortical and cancellous bone thickness in the right and left iliac crests were performed using bone window protocol on computed tomography scans. Statistical significance was determined using a 2-tailed t test. RESULTS: The interobserver interclass correlation coefficient reliability (N=2) for measurements at the right iliac crest is 0.895 (95% confidence interval, 0.852-0.925), and the interclass correlation coefficient for the left iliac crest is 0.912 (95% confidence interval, 0.877-0.938). A statistically significant difference in the mean cancellous bone ratio was found between American black (0.667±0.065) and American white (0.750±0.051) groups (P<0.001). CONCLUSIONS: At the iliac crest, American black patients had a lower mean ratio of cancellous to the total bone as compared with American white patients. This population may benefit from alternative graft options. While iliac crest autograft remains the first option for fusion surgeries, alternative options should be considered to ensure that each patient receives the best-personalized care.

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

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

Impact of Preoperative Total Knee Arthroplasty on Radiological and Clinical Outcomes of Spinal Fusion for Concurrent Knee Osteoarthritis and Degenerative Lumbar Spinal Diseases.

Concurrent knee osteoarthritis (KOA) and degenerative lumbar spinal disease (LSD) has increased, but the total knee arthroplasty (TKA) effect on degenerative LSD remains unclear. The aim of this study was to retrospectively analyze to compare radiological and clinical outcomes between spinal fusion only and preoperative TKA with spinal fusion for the patients with concurrent KOA and degenerative LSD. A total of 72 patients with concurrent KOA and degenerative LSDs who underwent spinal fusion at less than three levels were divided in two groups: non-TKA group (n = 50) and preoperative TKA group (n = 22). Preoperative lumbar lordosis (LL) was significantly lower in the preoperative TKA group than the non-TKA group (p < 0.05). Significantly higher preoperative pelvic incidence (PI), PI/LL mismatch, and pelvic tilt (PT) occurred in preoperative TKA group than non-TKA group (all p < 0.05). There was significant improvement of postoperative Oswestry Disability Index and leg Visual Analog Scale in the preoperative TKA group (all p < 0.01). Preoperative TKA could be a benefit for in proper correction of sagittal spinopelvic alignment by spinal fusion. Therefore, preoperative TKA could be considered a preceding surgical option for patients with severe sagittal spinopelvic parameters in concurrent KOA and degenerative LSD.

Infra-adjacent Segment Disease After Lumbar Fusion: An Analysis of Pelvic Parameters.

STUDY DESIGN: Cross-sectional observational cohort study. OBJECTIVE: The aim of this study was to determine the incidence and risk factors associated with the development of sacroiliac joint (SIJ) dysfunction following lumbosacral fusion. SUMMARY OF BACKGROUND DATA: Adjacent segment degeneration to both proximal and distal areas of spinal fusion is a postoperative complication of lumbar fusion. Various studies examined supra-adjacent degeneration following lumbar fusion, but few focused on infra-adjacent degeneration. In lumbosacral fusion, fusion extends to the sacrum, placing increased stress on the SIJ. METHODS: A total of 2069 sequential patients who underwent lumbosacral fusion surgery from 2008 to 2018 at a single academic medical center were retrospectively reviewed. Patients who subsequently developed SIJ dysfunction were identified. SIJ dysfunction was defined as patients who met the diagnostic criteria with physical examination and received an SIJ injection with clinical evidence of improvement. Controls, without subsequent SIJ dysfunction, were matched with cases based on levels of fusion, age, sex, and body mass index. Pre-and postoperative pelvic parameters were measured, including pelvic incidence, pelvic tilt (PT), sacral slope, lumbar lordosis, lumbosacral angle, L4 incidence and L5 incidence. RESULTS: Of 2069 patients who underwent lumbosacral fusion, 81 patients (3.9%) met criteria for SIJ dysfunction. Measurements were made for 47 of 81 patients who had SIJ dysfunction, that had both pre- and post-operative imaging. Measurements for 44 matched controls were taken. Postoperative PT was significantly lower in SIJ dysfunction patients compared to controls (20.82°â€Š±â€Š2.19° vs. 27.28°â€Š±â€Š2.30°; P < 0.05), as was L5 incidence (28.64°â€Š±â€Š3.38° vs. 37.11°â€Š± 3.50°; P < 0.05). CONCLUSION: Incidence of the SIJ dysfunction after lumbosacral fusion surgery was 3.9% and these patients had a significantly lower PT and L5 incidence compared to the control group. Significantly low PT may be derived from weak hamstring muscles, predisposing a patient to SIJ dysfunction. Therefore, hamstring muscle strengthening exercise for patients with decreased PT after lumbosacral fusion may decrease the incidence of SIJ dysfunction.Level of Evidence: 3.

Sacroiliac joint dysfunction: pathophysiology, diagnosis, and treatment.

PURPOSE: To review the anatomy and function of the sacroiliac joint (SIJ), as well as the pathophysiology, clinical presentation, diagnostic criteria, and treatment options for SIJ dysfunction. METHODS: The SIJ serves an extremely crucial function in mobility, stability, and resistance against shear forces. Joint mobility becomes increasingly limited with age-related cartilaginous changes that begin in puberty and continue throughout life. Pain can also be localized to the SIJ itself, known as SIJ dysfunction. A literature review was performed on the anatomy, etiology, risk factors, diagnostic modalities, and treatment options for SIJ dysfunction. RESULTS: SIJ dysfunction is an under-recognized source of low back pain. Dysfunction can result from various clinical conditions, as well as abnormal motion or malalignment of the joint. Diagnosis and evaluation of SIJ dysfunction are difficult, with use of physical maneuvers and image-guided anesthetic injection. Non-operative treatment options are considered first-line due to high surgical complication rates. Such options include conservative management, radiofrequency treatment, nerve blocks, and articular injections. Surgical management involves open and percutaneous approaches. CONCLUSION: With the aging nature of the population, SIJ dysfunction has emerged as an extremely prevalent issue. Current research into the pathophysiology and risk factors of SIJ dysfunction is extremely important for planning preventative and therapeutic strategies. Various treatment options exist including conservative management, radiofrequency, nerve blocks, intra-articular or peri-articular injections, and surgical fixation. Improved diagnostic methods in clinical practice are thus critical to properly identify patients suffering from SIJ dysfunction, plan early intervention, and hasten return to function. LEVEL OF EVIDENCE I: Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Overview and Spinal Implications of Leg Length Discrepancy: Narrative Review.

Leg length discrepancy (LLD) is an underrecognized and prevalent condition among the U.S. population, with effects varying depending on the cause and size of the discrepancy. LLD occurs when the paired lower extremities are unequal in length and can be etiologically classified as functional or structural. Length differences are typically less than 10 mm and asymptomatic or easily compensated for by the patient through self-lengthening or shortening of the lower extremities. Literature review of the etiology, diagnostic modalities, clinical complications, and treatment option for patients with LLD. LLD can be assessed directly through tape measurements or indirectly through palpation of bony landmarks. Imaging modalities, specifically radiography, are more precise and help identify coexistent deformity. Once LLD has been diagnosed, evaluation for potential adverse complications is necessary. Discrepancies greater than 20 mm can alter biomechanics and loading patterns with resultant functional limitations and musculoskeletal disorders, such as functional scoliosis. Functional scoliosis is nonprogressive and involves a structurally normal spine with an apparent lateral curvature, which regresses fully or partially when the LLD is corrected. Long-standing LLD and functional scoliosis often result in permanent degenerative changes in the facet joints and intervertebral discs of the spine. Further understanding of the contribution of LLD in the development of scoliosis and degenerative spine disease will allow for more effective preventative treatment strategies and hasten return to function.

Pelvic obliquity associated with neuromuscular scoliosis in cerebral palsy: cause and treatment.

STUDY DESIGN: Literature Review. OBJECTIVE: Review the etiology, clinical manifestations, diagnosis, and treatment of pelvic obliquity in cerebral palsy patients with neuromuscular scoliosis. Neuromuscular scoliosis (NMS) in cerebral palsy (CP) patients is rapidly progressive and often leads to an imbalance in musculoskeletal mechanics that extends to the pelvis. A horizontal misalignment of the pelvis in the frontal plane known as pelvic obliquity (PO) is a common finding in this population. When untreated, PO can exacerbate the back pain, postural strain, and walking difficulties experienced by these patients. Establishing the manifestation and treatment plan for PO in the setting of NMS can provide valuable insight for diagnosis and management. METHODS: A comprehensive literature review was performed on the etiology, clinical manifestations, diagnosis, and treatment of pelvic obliquity in the setting of NMS in CP. The advantages and limitations of measurement and treatment options were evaluated. RESULTS: PO is categorized into suprapelvic, infrapelvic, and intrapelvic causes, each presenting with a unique pattern of pathology. NMS in CP with hip contractures and structural deformities fall into these categories. The Maloney and O'Brien methods of pelvic measurement have demonstrated superior utility and are recommended for clinical diagnosis. The management of PO in NMS patients is focused on the cause of malalignment, with posterior fusion, contracture release, and osteotomy encompassing the mainstay of treatment. CONCLUSION: PO is commonly found in patients with NMS in cerebral palsy. There is currently no standard method for determining the PO angle. Interventions designed to reduce scoliotic curves and release tissue contractures can level the pelvis and restore proper alignment of the spine and sacrum in the coronal plane in these patients. Further understanding of the causes of PO in NMS, as well as the establishment of a standardized measuring technique and diagnostic parameters will allow for more effective treatment options and improve outcomes in patients with CP. LEVEL OF EVIDENCE: N/A.

Trends in topics presented as posters at the Scoliosis Research Society (SRS) annual meetings for the last 7 years: implications of an SRS annual meeting abstract registry (Part II).

PURPOSE: Analyzing and comparing past Scoliosis Research Society (SRS) poster and podium presentations would allow members to see trends in areas of interest and help authors guide future research efforts. METHODS: Abstract books from 2011 to 2017 were retrieved and titles were extracted. From each title and abstract body, keywords were identified and collected. Keywords were categorized into several groups: subjects of study, topics not related to treatment, conservative treatment, surgery, treatment result, complications, revision, long-term follow-up, cost, and questionnaire. Each category was subcategorized based on specific topics. Assignments of keywords were manually checked against their abstracts. The frequency of each keyword was ranked to represent areas of interest and trended according to year. The results were compared to trends in podium presentations. RESULTS: The most popular keywords in each group were similar to those of the podium presentations. There has been an increasing trend for: Early Onset Scoliosis, Radiographic Diagnosis, and Sagittal Alignment. There has been a decreasing trend for: Neuromuscular, X-ray, Posterior Surgery, Osteotomy, Pedicle Screws, Mental Failure/Misplaced Screw, Revision, and Hospital Stay. The distribution of topics of the poster presentation was not significantly different from those of podium presentation, but podium has more long-term follow-up studies. CONCLUSION: We report trends in SRS poster presentations. We found no significant difference between the topics of poster and those of podium presentations. We hope this data could help members better prepare for future meetings.

Ultrasound-guided ethanol ablation for cystic thyroid nodules: effectiveness of small amounts of ethanol in a single session.

PURPOSE: The aim of this study was to evaluate the efficacy of ethanol ablation (EA) in the treatment of cystic thyroid nodules using low-dose ethanol regardless of the initial volume of the nodule or properties of the aspirate. METHODS: Sixty-one nodules in 60 patients were treated with EA from October 2013 to January 2020. In each patient, EA was performed only once, using less than 5 mL of ethanol (99.5%) instilled and removed completely after a few minutes of retention. Nodule volume, the symptom score, the cosmetic score, and complications were evaluated before and after treatment. The therapeutic success rate (TSR) and volume reduction rate (VRR) according to nodule volume and properties of the aspirate were evaluated. Therapeutic success was defined as the absence of any residual fluid or sufficient volume reduction (≥50%) with improvement of nodule-related symptoms. RESULTS: The 61 nodules comprised 38 pure cysts and 23 predominantly cystic nodules. The initial nodule volume was 21.9±15.2 mL (range, 4.4 to 77.2 mL). The TSR was 88.5% (100% in pure cysts and 69.6% in predominantly cystic nodules, P<0.001). The TSR of pure cysts was 100% regardless of nodule volume and properties of the aspirate. In predominantly cystic nodules, the TSR and VRR gradually decreased as volume increased. One patient experienced arrhythmia during the procedure, but completely recovered without sequelae. CONCLUSION: Single-session EA using low-dose ethanol might be effective for the treatment of symptomatic cystic thyroid nodules regardless of the initial cyst volume and properties of the aspirate, especially in pure cysts.