Adolescent Idiopathic Scoliosis: Increased Body Mass Associated with Decreased Bracing Outcomes.

Bracing reduces the need for surgical intervention in patients with adolescent idiopathic scoliosis (AIS). However, bracing outcomes with variable body mass index (BMI) are understudied. The authors sought to determine the association of BMI with bracing outcomes. The authors performed a retrospective cohort study of 104 patients presenting with AIS. Initial Risser score, hours of bracing per day, BMI percentile, and curve magnitude pre- and postbracing were collected. There was no detectable difference between years of brace wear or primary curve magnitude at time of presentation between both groups. Overall, 29% (25/87) of underweight/normal weight patients and 59% (10/17) of overweight/obese patients had curves ≥ 45 degrees at the end of bracing (p = 0.016). Odds of having a curve ≥ 45 degrees after bracing were 3.5 (95% confidence interval: 1.2 to 10.3, p = 0.021) times higher for overweight/obese patients compared with underweight/normal weight patients. Increased overlying adipose tissue may reduce the corrective forces required to straighten the spine. (Journal of Surgical Orthopaedic Advances 33(1):029-032, 2024).

Single Stage Combined Approach Sagittal En-Block Spondylectomy for L3 Vertebral Chondrosarcoma: A Technical Note.

BACKGROUND: Primary malignant tumors of the spine are rare which most commonly occur in lumbar and thoracic vertebra. Here, we report a rare case of retroperitoneal chondrosarcoma of the L3 vertebra which was managed with sagittal en-block spondylectomy following chemoradiation. CASE PRESENTATION: A 26-year-old lady was evaluated for abdominal pain with contrast enhanced computer tomogram of abdomen and pelvis which revealed a soft tissue retroperitoneal mass arising from L3 vertebra. She underwent laparotomy and biopsy which revealed chondrosarcoma and she received chemoradiation over a period of 28 weeks, 6 days. After re-imaging she underwent single stage combined approach sagittal en-block spondylectomy of retroperitoneal chondrosarcoma of L3 vertebra with right nephrectomy and spine reconstruction. She was followed for a period of 3 years, there was no evidence of recurrence in follow-up CECT abdomen and pelvis. She has no gait abnormality or spinal deformity. CONCLUSION: Sagittal en-block spondylectomy is a preferred surgical approach for eccentrically placed spinal tumors which offers better oncological and functional outcomes.

Preference Signaling Survey of Program Directors-After the Match.

INTRODUCTION: The 2022 to 2023 orthopaedic residency cycle implemented a preference signaling program (PSP), allowing applicants to send "signals" to up to 30 programs to demonstrate their genuine interest. With the conclusion of the 2022 to 2023 cycle, the primary purpose of this study was to analyze program director (PD) perceptions of the PSP after the match cycle and provide a retrospective evaluation of the effects of the PSP on the orthopaedic resident selection process. METHODS: A 21-question survey was distributed to 98 PDs (32.7% response rate). Contact information was obtained from a national database. RESULTS: Most respondents (96.9%) participated in the American Orthopaedic Association's PSP. The majority (93.7%) view preference signaling as a positive change. Most PDs (56.2%) reported a decreased number in applications received compared with previous years. Receiving a preference signal was ranked among the most important factors in resident selection, and most PDs agreed that preference signaling should be used to screen applicants (84.4%) and differentiate similar applicants (96.8%). Moreover, 65.6% of PDs indicated that they would not rank or invite applicants to interview without a signal or completion of a formal away rotation. PDs report that in the 2022 to 2023 cycle, 98.5% of applicants who matched at their program had sent a preference signal. DISCUSSION: Preference signaling was one of the most important factors assessed during its inaugural application cycle and is anticipated to remain a key tool for screening and differentiating candidates. Applicants should strategically select signal recipients to enhance their success in the match.

Systematic review and meta-analysis on the efficacy of Indian polyvalent antivenom against the Indian snakes of clinical significance.

Snakebite in India is a severe problem as it causes a mortality rate of 58,000 and a disability rate of 140,000 every year which is the highest among any other country. Antivenom is the primary therapy for snakebite, and its manufacturing techniques have essentially stayed unaltered for over a century. Indian polyvalent antivenom, a scientifically validated medicine for treating the toxic effects of snakebites, is available against the venom of the so-called Big Four snakes namely Spectacled cobra (Naja naja), Saw-scaled viper (Echis carinatus), Russell's viper (Daboia russelli) and the Common krait (Bungarus caeruleus), responsible for majority of the deaths in India. India hosts many other species of snakes, including cobras, kraits, saw-scaled vipers, sea snakes, and pit vipers, responsible for clinically severe envenomation. Neutralization strategy has been applied to access the efficacy of antivenoms, crucial for reducing snake bite deaths and disabilities. This review aims to conduct a systematic review and meta-analysis on the neutralization efficiency of the Polyvalent Antivenom (PAV) and focus on the factors that may contribute to the poor recognition of the antivenom towards the venom toxins. Reports focusing on the investigation of antivenom efficacy were searched and collected from several databases. Preclinical studies that reported the neutralization efficacy of the commercial antivenom against the medically important snakes of India were included. The articles were screened based on the inclusion criteria and 8 studies were shortlisted for meta-analysis. Pooled proportion was calculated for the antivenom efficacy reported by the studies and was found to be statistically significant with a 95% confidence interval. The heterogenicity in the venom toxicity and neutralization potency of the antivenom was evident in the overall estimate (proportion) and individual data. We provide comprehensive evidence on antivenom efficacy against medically important snakes from various parts of India which may aid in identifying the gaps in snake envenomation therapy and the need for novel potentially improved treatment of snakebites.

Activating mutations drive human MEK1 kinase using a gear-shifting mechanism.

There is an unmet need to classify cancer-promoting kinase mutations in a mechanistically cognizant way. The challenge is to understand how mutations stabilize different kinase configurations to alter function, and how this influences pathogenic potential of the kinase and its responses to therapeutic inhibitors. This goal is made more challenging by the complexity of the mutational landscape of diseases, and is further compounded by the conformational plasticity of each variant where multiple conformations coexist. We focus here on the human MEK1 kinase, a vital component of the RAS/MAPK pathway in which mutations cause cancers and developmental disorders called RASopathies. We sought to explore how these mutations alter the human MEK1 kinase at atomic resolution by utilizing enhanced sampling simulations and free energy calculations. We computationally mapped the different conformational stabilities of individual mutated systems by delineating the free energy landscapes, and showed how this relates directly to experimentally quantified developmental transformation potentials of the mutations. We conclude that mutations leverage variations in the hydrogen bonding network associated with the conformational plasticity to progressively stabilize the active-like conformational state of the kinase while destabilizing the inactive-like state. The mutations alter residue-level internal molecular correlations by differentially prioritizing different conformational states, delineating the various modes of MEK1 activation reminiscent of a gear-shifting mechanism. We define the molecular basis of conversion of this kinase from its inactive to its active state, connecting structure, dynamics, and function by delineating the energy landscape and conformational plasticity, thus augmenting our understanding of MEK1 regulation.

Consensus-Based Best Practice Guidelines for the Management of Spinal Deformity and Associated Tumors in Pediatric Neurofibromatosis Type 1: Screening and Surveillance, Surgical Intervention, and Medical Therapy.

BACKGROUND: Spinal conditions, such as scoliosis and spinal tumors, are prevalent in neurofibromatosis type 1 (NF1). Despite the recognized importance of their early detection and treatment, there remain knowledge gaps in how to approach these manifestations. The purpose of this study was to utilize the experience of a multidisciplinary committee of experts to establish consensus-based best practice guidelines (BPGs) for spinal screening and surveillance, surgical intervention, and medical therapy in pediatric patients with NF1. METHODS: Using the results of a prior systematic review, 10 key questions that required further assessment were first identified. A committee of 20 experts across medical specialties was then chosen based on their clinical experience with spinal deformity and tumors in NF1. These were 9 orthopaedic surgeons, 4 neuro-oncologists/oncologists, 3 neurosurgeons, 2 neurologists, 1 pulmonologist, and 1 clinical geneticist. An initial online survey on current practices and opinions was conducted, followed by 2 additional surveys via a formal consensus-based modified Delphi method. The final survey involved voting on agreement or disagreement with 35 recommendations. Items reaching consensus (≥70% agreement or disagreement) were included in the final BPGs. RESULTS: Consensus was reached for 30 total recommendations on the management of spinal deformity and tumors in NF1. These were 11 recommendations on screening and surveillance, 16 on surgical intervention, and 3 on medical therapy. Five recommendations did not achieve consensus and were excluded from the BPGs. CONCLUSION: We present a set of consensus-based BPGs comprised of 30 recommendations for spinal screening and surveillance, surgical intervention, and medical therapy in pediatric NF1.

Professional Society Opportunities and Involvement for Early-Career Orthopaedic Surgeons.

Professional societies can provide orthopaedic surgeons opportunities to build strong fellowship among colleagues within a specialty, to gain leadership positions and responsibilities, and to contribute to the latest research and practice management guidelines. However, early-career surgeons often receive little to no guidance about how membership can benefit them in the long term. The primary purpose of this review article was to provide an overview of orthopaedic professional societies, why early-career orthopaedic surgeons should consider membership, and how they can get involved. Topics discussed in this article include the missions of various societies, value in career advancement both in academic and private practice settings, benefits to patient care, and tips for budding surgeons on how to rise up the ranks within a given professional society. We also provide a comprehensive list of leadership development, fellowship, mentorship, and research opportunities that are designed for orthopaedic surgeons within their first 10 years of practice.

Compression Screw Fixation for Pediatric Olecranon Fractures.

BACKGROUND: Pediatric olecranon fractures can be treated with several methods of fixation. Though postoperative outcomes of various fixation techniques, including cannulated intramedullary screws, have been described in adults, functional and radiographic outcomes of screw fixation in pediatric patients are unclear. In this study, we assessed clinical, radiographic, functional, and patient-reported outcomes of pediatric olecranon fractures treated with compression screw fixation. METHODS: We retrospectively identified 37 patients aged 16 years or younger with a total of 40 olecranon fractures treated with screw fixation at our level-1 trauma center between April 2005 and April 2022. From medical records, we extracted data on demographic characteristics, time to radiographic union, range of elbow motion at final follow-up, and complications during the follow-up period. Patient-reported outcomes were evaluated using the Quick Disabilities of the Arm, Shoulder, and Hand and Patient-Reported Outcomes Measurement Information System Pediatric Upper Extremity Short Form 8a measures. RESULTS: There were no malunions or nonunions at the final mean follow-up of 140 days (range, 26 to 614 d). Four patients had implant failure (11%), of whom 3 experienced fracture union with no loss of fixation or need for revision surgery. One patient underwent a revision for fracture malreduction. Screw prominence was documented in 1 patient. Instrumentation was removed at our institution for 33 of 40 fractures. Mean time to radiographic union was 53 days (range, 20 to 168 d). Postoperative range of motion at the most recent follow-up visit showed a mean extension deficit of 6 degrees (range, 0-30 degrees) and mean flexion of 134 degrees (range, 60-150 degrees). At the final follow-up, the mean (±SD) Quick Disabilities of the Arm, Shoulder, and Hand score was 4.2±8.0, and the mean Patient-Reported Outcomes Measurement Information System score was 37±1.5, indicating good function and patient satisfaction. CONCLUSIONS: All 37 patients in our series had excellent radiographic, functional, and patient-reported outcomes after screw fixation. We observed no cases of nonunion or malunion, growth disturbance, or refracture. These results suggest that screw fixation is a safe and effective option for pediatric olecranon fractures. LEVEL OF EVIDENCE: Level IV, case series.

Renal FGF23 signaling depends on redox protein Memo1 and promotes orthovanadate-sensitive protein phosphotyrosyl phosphatase activity.

Memo1 deletion in mice causes premature aging and an unbalanced metabolism partially resembling Fgf23 and Klotho loss-of-function animals. We report a role for Memo's redox function in renal FGF23-Klotho signaling using mice with postnatally induced Memo deficiency in the whole body (cKO). Memo cKO mice showed impaired FGF23-driven renal ERK phosphorylation and transcriptional responses. FGF23 actions involved activation of oxidation-sensitive protein phosphotyrosyl phosphatases in the kidney. Redox proteomics revealed excessive thiols of Rho-GDP dissociation inhibitor 1 (Rho-GDI1) in Memo cKO, and we detected a functional interaction between Memo's redox function and oxidation at Rho-GDI1 Cys79. In isolated cellular systems, Rho-GDI1 did not directly affect FGF23-driven cell signaling, but we detected disturbed Rho-GDI1 dependent small Rho-GTPase protein abundance and activity in the kidney of Memo cKO mice. Collectively, this study reveals previously unknown layers in the regulation of renal FGF23 signaling and connects Memo with the network of small Rho-GTPases.

Social Media Presence Is Associated With Diversity and Application Volume for Orthopedic Surgery Residency Programs.

The purpose of this study was to assess the association between social media presence (Twitter and Instagram), diversity in orthopedic surgery residency programs, and the number of applications received by a program. Data from Twitter and Instagram for 179 orthopedic residency programs accredited by the Accreditation Council for Graduate Medical Education were collected, including the presence of a social media account, date of first post, number of posts, and number of followers. Residency program data were collected from the Association of American Medical Colleges Residency Explorer Tool and included percentage of Whiteresidents, percentage of male residents, residency ranking, and number of applications submitted during the 2019 application cycle. Bivariate and multivariable analyses were performed with adjustment for program ranking. Of 179 residency programs, 34.6% (n=62) had Twitter, and 16.7% (n=30) had Instagram. Overall, 39.7% (n=71) had a social media presence, defined as having at least one of the two forms of social media. Programs with social media presences had higher average rankings (48.1 vs 99.6 rank, P<.001). After adjusting for program ranking, social media presence was associated with increased applications during the 2019 application cycle (odds ratio [OR]=2.76, P=.010). Social media presence was associated with increased odds of gender diversity (OR=3.07, P=.047) and racial diversity (OR=2.21, P=.041). Individually, Twitter presence was associated with increased odds of gender (OR=4.81, P=.018) and racial diversity (OR=4.00, P=.021), but Instagram was not (P>.05). Social media presence is associated with more residency program applications and increased resident diversity. Social media can be used to highlight inclusivity measures and related opportunities. [Orthopedics. 2023;46(1):47-53.].

Racial Disparities in Spine Surgery: A Systematic Review.

STUDY DESIGN: Systematic Review. OBJECTIVES: To synthesize previous studies evaluating racial disparities in spine surgery. METHODS: We queried PubMed, Embase, Cochrane Library, and Web of Science for literature on racial disparities in spine surgery. Our review was constructed in accordance with Preferred Reporting Items and Meta-analyses guidelines and protocol. The main outcome measures were the occurrence of racial disparities in postoperative outcomes, mortality, surgical management, readmissions, and length of stay. RESULTS: A total of 1753 publications were assessed. Twenty-two articles met inclusion criteria. Seventeen studies compared Whites (Ws) and African Americans (AAs) groups; 14 studies reported adverse outcomes for AAs. When compared with Ws, AA patients had higher odds of postoperative complications including mortality, cerebrospinal fluid leak, nervous system complications, bleeding, infection, in-hospital complications, adverse discharge disposition, and delay in diagnosis. Further, AAs were found to have increased odds of readmission and longer length of stay. Finally, AAs were found to have higher odds of nonoperative treatment for spinal cord injury, were more likely to undergo posterior approach in the treatment of cervical spondylotic myelopathy, and were less likely to receive cervical disk arthroplasty compared with Ws for similar indications. CONCLUSIONS: This systematic review of spine literature found that when compared with W patients, AA patients had worse health outcomes. Further investigation of root causes of these racial disparities in spine surgery is warranted.

Rate of Tibiotalocalcaneal (TTC) Fusion Using the Surgical Implant Generation Network (SIGN) Intramedullary Nail in Developing Countries.

Outcomes of the Surgical Implant Generation Network (SIGN) nail have been reported for femur and tibial fractures, but its use in tibiotalocalcaneal arthrodesis (TTCA) is not well studied. Radiographic and clinical outcomes of TTCA using the SIGN database in patients with > 6 months of radiographic follow up were analyzed. Rates of tibiotalar (TT) fusion and subtalar (ST) fusion at final follow up were assessed by two independent reviewers. Of the 62 patients identified, use of the SIGN nail for TCCA resulted in 53% rate of fusion in the TT joint and 20% in the ST joint. Thirty-seven patients (60%) demonstrated painless weight bearing at final follow up. There were no differences in incidence of painless weight bearing between consensus fused and not fused cohorts for TT and ST joints (p > 0.05). There were five implant failures, no cases of infection, and seven cases of reoperation. (Journal of Surgical Orthopaedic Advances 32(3):187-192, 2023).

Preference Signaling for Orthopaedic Surgery Applicants: A Survey of Residency Program Directors.

INTRODUCTION: On March 30, 2022, the American Orthopaedic Association's Council of Orthopaedic Residency Directors announced its endorsement for a preference signaling program (PSP) for the 2022 to 2023 orthopaedic residency application cycle. The purpose of our study was to assess orthopaedic surgery residency program director (PD) perceptions of the PSP and analyze potential effects of the PSP on the residency application process. METHODS: A 19-question survey was distributed to 98 PDs (40.8% response rate). Contact information was obtained from a national database. RESULTS: Most programs plan to participate in the PSP (87.5%). Preference signaling is highly regarded for residency selection, with PDs ranking its relative importance just below away rotation performance and personal knowledge of the applicant. Most PDs agreed that applicants will have increased chances of receiving interviews at programs they send a preference signal (65%). Most PDs also do not think that the PSP will help improve diversity (42.5%) and combat the overapplication phenomenon (67.5%). A majority think that an application cap limiting the total number of applications submitted should be initiated in future application cycles (85%). CONCLUSION: Preference signaling will be one of the most important factors considered during orthopaedic residency selection. A signal will likely improve applicants' chance of receiving an interview. Thus, students should be selective about where they send their preference signals and invest time in creating strong, personal connections with a few, select programs to increase their success in the orthopaedic residency match.

Biomechanical analysis of dual versus lateral locked plating in elderly bicondylar tibial plateau fractures: Does medial comminution matter?

OBJECTIVE: To assess dual plating versus lateral locked plate fixation of bicondylar tibial plateau fractures in an elderly cadaveric model with and without medial bone loss PARTICIPANTS: 10 pairs of elderly (range 78-93 years of age) fresh frozen tibias. INTERVENTION: Bicondylar tibial plateau fractures were created reproducing AO/OTA 41 C1 (without medial bone loss) and C2 fractures (with medial bone loss). Cadavers were randomized to 4 different groups. Groups 1 and 2 were 41 C1 fractures and fixated with either dual or lateral plating, respectively. Groups 3 and 4 were fixated in a similar fashion with medial metaphyseal bone loss (41 C2 fracture) with dual plating Group 3 and lateral plating group 4. Lateral plating consisted of a 3.5 mm 5-hole lateral plate (ALPS, ZimmerBiomet) with 6 bicortical locking screws proximally and two diaphyseal screws. Dual plating groups underwent lateral plating and additional 3.5 mm 5-hole posteromedial 1/3 tubular plate (ZimmerBiomet) placed at the apex of the fracture with two shaft screws and one unicortical screw proximally. Specimens were tested in a Mechanical Testing System (MTS) machine loading both condyles. OUTCOME MEASUREMENTS: Specimens were loaded to 300 N and coronal alignment obtained. Specimens were then cycled from 100 N to 700 N for 5000 cycles at 2 Hz. Average axial displacement, maximal displacement, average force and coronal alignment after 5000 cycles were recorded. Lastly, force to failure was recorded at 100 N/sec. RESULTS: Mean axial displacement was 4.21 mm ranging from 3.12 mm in group 1 to 5.92 mm in group 4 (P = 0.51). Failure force averaged 3340 N ranging from 4342 N in group 1 to 2433 N in group 4 (P = 0.36). Maximal displacement ranged from 3.69 mm in group 1 to 7.37 mm in group 4 (P = 0.21). Change in coronal alignment ranged from 0.98° in group 1 to 1.97° in group 4 (P = 0.45). No statistically significant difference was noted between all four groups for all data points. CONCLUSION: The results of this study demonstrate that a lateral locked plate may offer an alternative means of fixation in AO/OTA 41 C1 and C2 fractures.

Minimizing the Risk of Vascular Injury: Anatomy of the Popliteal Artery in the Pediatric Knee.

BACKGROUND: Displaced pediatric tibial tubercle fractures are commonly stabilized with screws directed posteriorly toward neurovascular structures. Here, we (1) characterize the variation of the popliteal artery among pediatric patients; and (2) recommend a safe screw trajectory for fixation of tibial tubercle fractures. METHODS: We retrospectively identified 42 patients (42 knees; 29 female) aged 12-17 years with lower-extremity magnetic resonance imaging (MRI) at a tertiary academic center. The mean patient age was 14.5 (range: 12-17) years, and the mean body mass index value was 19.1 (range: 14.9-25.1). We included patients with open physes or visible physeal scars and excluded those with prior instrumentation or lower-extremity injury. Using sagittal MRI, we measured the distances from 5 levels each on the anterior and posterior tibial cortex to the popliteal artery (level 1, midpoint of proximal tibial epiphysis; level 2, the proximal extent of the tubercle; level 3, tubercle prominence; level 4, 2 cm distal to the proximal extent of the tubercle; level 5, 4 cm distal to the proximal extent of the tubercle). Using coronal MRI, we measured the width of the tibia at each level and the distance from the lateral-most and medial-most cortex to the artery. RESULTS: The popliteal artery was laterally positioned in all knees. The mean distance between the artery and lateral-most aspect of the tibia at each level ranged from 1.9 to 2.4 cm, and from 2.3 to 3.9 cm from the medial-most aspect of the tibia. The mean distance that a screw can advance before vascular injury was 5.1 cm at level 1. The shortest mean distance to the popliteal artery was 1.7 cm, at level 5. There is minimal distance between the posterior tibial cortex and the artery at all levels. CONCLUSIONS: Understanding the position of the popliteal artery in pediatric patients can help when stabilizing tibial tubercle fractures. Because the artery is close to the posterior cortex, a drill exiting in line with the popliteal artery risks vascular injury. Therefore, we recommend that screws exit within the medial 60% of the tibia. LEVEL OF EVIDENCE: IV.

Pedicle Screw Plowing in Adolescent Idiopathic Scoliosis: How Common Is It and Is It a Problem?

STUDY DESIGN: Multicenter retrospective review. OBJECTIVE: To calculate overall incidence of pedicle screw "plowing" in adolescent idiopathic scoliosis (AIS) patients who underwent posterior spinal fusion (PSF). To identify risk factors for pedicle screw plowing and associated postoperative outcomes, including loss of correction and revision rate. SUMMARY OF BACKGROUND DATA: Curve correction of AIS generates perpendicular stresses that can cause pedicle screws to lose alignment and "plow" through pedicles craniocaudally. METHODS: We reviewed records of 1057 patients who underwent PSF for AIS from 2002 to 2015. Preoperative and first postoperative erect radiographs were evaluated by two observers to determine (1) presence of plowing and (2) subsequent loss of correction (LOC). Plowing was defined as more than 25° sagittal angulation compared with pedicle axis or entry of the most dorsal part of the screw outside the pedicle projection. LOC was defined as postoperative change in focal angulation of an instrumented spinal level, when in consensus of both reviewers. Bivariate analyses were performed (alpha = 0.05). RESULTS: Nineteen thousand five hundred sixty nine screws were assessed across our cohort of 1057 patients. Both observers agreed that 48 patients (4.5%) demonstrated plowing of more than or equal to one pedicle screw. For 72 screws (0.4%), both observers noted plowing, most commonly through the cranial cortex of the pedicle (65/72 screws) and at the lowest instrument vertebra (LIV) (17/72 screws). Factors associated with plowing included larger curves (P = 0.02); lower mean pedicle screw density (P = 0.0003); skeletal immaturity as measured by open triradiate cartilage (P = 0.04); and younger chronological age at time of surgery (P = 0.04). LOC occurred in 13 patients, most commonly at LIV (P < 0.0001). Revision rate for loss of screw fixation was higher in the plowing group (P = 0.003). CONCLUSION: Pedicle screw plowing occurred in 4.5% of AIS patients, especially in those skeletally immature and with decreased implant density. Plowing commonly occurred in the cranial direction and was associated with LOC, particularly at the LIV.Level of Evidence: 3.

Sacral-Alar-Iliac (SAI) Fixation in Children With Spine Deformity: Minimum 10-Year Follow-Up.

INTRODUCTION: Sacral-alar-iliac (SAI) screws are utilized to achieve pelvic fixation in spine deformity patients. The primary purpose of this study is to investigate the long-term outcomes of pediatric patients with scoliosis treated with posterior spinal fusion and SAI fixation at 10-year clinical and radiographic follow-up. METHODS: We reviewed the clinical and radiographic records of patients aged 18 years or below treated for scoliosis with posterior spinal fusion using SAI fixation. Pelvic obliquity and the major coronal curve were determined at the preoperative visit and 6-week, 1-year, 5-year, and 10-year postoperative visits. SAI screw-specific data collected included screw dimensions, rate of screw revision, pain at the SAI screw sites, presence of lucency >2 mm around the screw, screw loosening or breaking, and deep surgical site infections. RESULTS: Ninety-seven of 151 patients (75%) were included. The average age at index surgery was 13.5±3.1 years, and the most common diagnosis was cerebral palsy (67%). The mean duration of follow-up was 11±3 years. The mean pelvic obliquity measured 20±8.0 degrees preoperatively, and 8.7±4.0 degrees at the 10-year follow-up. There were no significant difference in pelvic obliquity when comparing the 10-year follow-up visit with the 6-week postoperative follow-up. Average screw dimensions were 8.4×68.8 mm. By the 10-year follow-up, 4 patients (4%) had at least 1 SAI screw-related complication. Of these patients, 2 (2%) had pain at 1 SAI screw, 4 (4%) had lucency around the screw, and 3 (3%) had broken or loose screws. Two (2%) required SAI screw revision because of late deep wound infection, and underwent exchange with a longer screw. There were no intrapelvic protrusions, vascular, or neurological complications. CONCLUSIONS: SAI screws are a safe and effective method for pelvic fixation in children with spinal deformity. The outcomes at ≥10 years are satisfactory, with low rates of long-term complications and excellent postoperative correction and subsequent maintenance of coronal curvature and pelvic obliquity over time. LEVEL OF EVIDENCE: Level IV.

Pelvic Osteotomy in Patients With Previous Sacral-Alar-Iliac (SAI) Fixation.

INTRODUCTION: Patients with neuromuscular disease are at high risk for developing hip dysplasia and scoliosis. The purpose of this study was to investigate the technical challenges and outcomes of pelvic osteotomy in patients with prior sacral-alar-iliac (SAI) fixation. METHODS: We reviewed clinical and radiographic records of patients aged 18 years and below who underwent pelvic osteotomy after SAI fixation. We recorded technical challenges during the osteotomy, time from SAI fixation to osteotomy, type of osteotomy, migration index, and distance from the SAI screw to the acetabulum. A 2-sample Wilcoxon rank-sum test was used to assess the data. RESULTS: Nineteen patients were included. Technical challenges were defined as having greater intraoperative fluoroscopy times and noted difficult osteotomy in the operative report. The mean time from SAI fixation to pelvic osteotomy was 2.2±1.5 years. For all 12 Chiari osteotomies, the ilium could not be laterally displaced; however, medial displacement of the distal segment of the osteotomy allowed adequate coverage. All 7 Dega osteotomies were performed by cutting the cortex at the tip of the SAI screw. The screw improved proximal leverage and provided a strong buttress for bone graft. The mean migration index before pelvic osteotomy was 59±19%, and at most recent follow-up was 13±4%. Twelve patients, who had a noted complicated osteotomy, had SAI screws that were ≤1.87 cm ( P <0.01) from the acetabulum and significantly increased intraoperative fluoroscopy time (1.76 vs. 1.18 min, P <0.01). CONCLUSIONS: The presence of SAI screws may cause iliac osteotomies to be technically challenging if the tip of the SAI screw is ≤1.87 cm to the acetabulum. When initially implanting SAI screws in neuromuscular patients, surgeons should attempt to place screw tips ∼2 cm from the acetabulum in the event these patients require subsequent pelvic osteotomy. LEVEL OF EVIDENCE: Level IV.

Sacral-Alar-Iliac (SAI) Fixation in Patients With Previous Pelvic Osteotomy.

STUDY DESIGN: This was a retrospective study. OBJECTIVE: The purpose of this study was to investigate the technical challenges and outcomes of sacral-alar-iliac (SAI) fixation for scoliosis in patients who had previously undergone a pelvic osteotomy for hip dysplasia. SUMMARY OF BACKGROUND DATA: Patients with neuromuscular disease are at high risk for developing hip dislocation and scoliosis. Surgical correction of one may affect the other. METHODS: We reviewed the records of patients aged 18 years and below who underwent spinal fusion using SAI screws after having undergone a pelvic osteotomy, with ≥2-year follow-up. We recorded the SAI screw dimensions, time from osteotomy to SAI fixation, type of osteotomy, and any complications performing SAI fixation due to the pelvic osteotomy. Bivariate statistics were used to analyze the data with statistical significance defined as P -value <0.05. RESULTS: Thirty-two patients were included. The average age was 10.3±3.2 years at pelvic osteotomy and 13.5±3.4 years at SAI fixation. Most patients had cerebral palsy (87.5%) and a unilateral Dega osteotomy (78.1%). Average screw dimensions were significantly shorter on the side of the osteotomy (66 vs. 72 mm, P <0.05). SAI screw placement was technically challenging in 8 patients (25%), due to pelvic distortion from the pelvic osteotomy. The use of a curved awl helped to find the intracortical channel. No patients had complications due to the SAI screw, and there were no significant differences in pelvic obliquity and major coronal curve correction. Two patients (6.3%) had screw lucency >2 mm around the SAI screw on the side of the pelvic osteotomy but no clinical symptoms. CONCLUSIONS: SAI fixation in patients with previous pelvic osteotomy is technically challenging due to pelvic morphology and prior implants. Often, a shorter SAI screw is required on the side of the osteotomy. However, outcomes in this patient population are satisfactory, with no significant complications at a 2-year follow-up. LEVEL OF EVIDENCE: Level IV.

Evaluation of a Slipped Capital Femoral Epiphysis Virtual Reality Surgical Simulation for the Orthopaedic Trainee.

OBJECTIVE: The purpose of this study was to compare outcomes between orthopaedic trainees using various preoperative training platforms (physical simulation [PS], virtual reality [VR], and reading/videos) in a slipped capital femoral epiphysis model. METHODS: Participants were randomly assigned to one of the three groups: (1) reading/video control group (n = 7), (2) VR group (n = 7), or (3) PS group (n = 7). Participants in the VR group completed a VR slipped capital femoral epiphysis module while participants in the PS group practiced the placement of a screw in the physical module before evaluation of percutaneous screw placement in the PS model. Outcomes evaluated included overall surgical time, amount of fluoroscopy, Global Rating Scale score, radiographic screw position, physical screw accuracy, presence of breeching of the articular surface or femoral neck, and overall platform rating (0 to 10). RESULTS: No difference was observed in surgical time, Global Rating Scale score, radiographic or physical accuracy of screw position, or articular surface breaching between the groups. Subjectively, there was a difference in utility of platform rating between the groups (PS: 10 ± 0, VR: 7 ± 2, and control: 6 ± 1, P = 0.001). CONCLUSION: Training with VR was subjectively rated higher in value compared with reading/video methods and had similar performance outcomes compared with training with PS.