Globus Medical (United States)

Developmental dysplasia of the hip (DDH) poses challenges for component positioning during total hip arthroplasty (THA) secondary to abnormal bone morphology, soft-tissue contractures, and hip center migration. The objective of this study was to evaluate the radiographic and clinical outcomes of THA for DDH performed with robotic assistance versus manual (M) technique. A retrospective review identified 115 patients with Crowe II to IV dysplasia undergoing primary THA at a single institution from 2016 to 2022. There were 59 (51%) M-THAs and 56 (49%) RA-THAs. The median age was 49 years, the median body mass index was 28, and 94 (82%) patients were women. No difference was seen in Crowe classification between cohorts. The mean follow-up was two years. No difference was observed in mean surgical time between robotic-assisted THA (RA-THA) and manual THA (M-THA) cohorts (118 vs. 135 minutes, P = 0.23). Postoperatively, there was no difference in leg length discrepancy or hip center restoration. The RA-THA cohort had a lower rate of acetabular implant malposition (inclination and/or anteversion; n = 7, 15%) versus the M-THA (n = 16, 40%) cohort ( P = 0.01). There were two (3%) dislocations in the M-THA cohort versus no dislocations in the RA-THA cohort ( P = 0.17). There were three (5%) revision surgeries in the M-THA cohort, including one acetabular revision for recurrent instability, one femoral implant revision for aseptic loosening, and one femoral osteotomy with retrograde intramedullary lengthening nail for residual leg length discrepancy correction. There were no revision surgeries in the RA-THA cohort ( P = 0.09) or component revisions ( P = 0.17). In this series of primary THA for DDH, RA-THA was associated with decreased rates of acetabular implant malpositioning. In addition, RA-THA trended toward lower rates of dislocation and revision surgery with equivalent surgical times to M-THA, demonstrating its feasibility and efficacy in primary THA for DDH.

Lateral lumbar interbody fusion (LLIF) is a minimally invasive surgical technique that provides a wide footprint interbody cage for correction of lumbar coronal and sagittal deformity. Traditional spinal interbody fusion procedures utilize pedicle screws and rods for additional stability. An expandable lateral titanium interbody cage with an integrated lateral fixation (eLLIFp) device provides a stand-alone LLIF that is intended to function autonomously. This may reduce the complexity of the surgery and the potential risks associated with supplemental posterior instrumentation. The minimum-acceptable screw length to promote adequate biomechanical fixation and stability for a stand-alone eLLIFp has not been determined. To investigate the effective ratio (of screw length/cage length) of a stand-alone eLLIFp construct that provides adequate biomechanical fixation and stability as compared to the eLLIFp with supplemental bilateral pedicle screw-rod fixation. In vitro cadaveric biomechanical testing and finite element modeling. Eight fresh-frozen human cadaveric lumbar spine specimens (L2-5) were used. Range-of-motion (ROM) measurements of intact and treated specimens with simulated stresses within the construct and surrounding bone during flexion-extension (FE), lateral bending (LB), and axial rotation (AR). Specimens with similar age and DEXA scores were selected. ROM of intact specimens was measured before treatment with LLIF at L3-4. Specimens were treated with expandable lateral cages with integrated fixation (stand-alone eLLIFp) or eLLIFp with supplemental posterior fixation using bilateral pedicle screws and rods (eLLIFp + BPS). ROM was measured using a custom-built 6°-of-freedom motion simulator (±7.5Nm) and normalized as a percentage of intact. Four patient-specific lumbar functional spinal unit finite element models (FEMs) were developed, validated, and then instrumented with eLLIFp stand-alone devices. The integrated screw lengths were varied to achieve screw-to-cage length ratios of 0.6, 0.75 and 0.9. Stresses were compared among the constructs under a 7.5Nm pure moment load in FE, LB, and AR. The stand-alone and posteriorly supplemented eLLIFp constructs were not sensitive to the ratio during FE and LB (with only a 4%-9% change in motion trends from low-to-high ratios, relative to intact). Independent of ratio, these constructs had minimal differences in FE and LB motion. However, during AR both constructs were sensitive to the ratio showing greater stability and less variability in performance with higher ratios (≥0.65). Regression analysis revealed that posteriorly supplemented eLLIFp constructs had a linear 13% reduction in AR motion as the ratio increased from low-to-high (p<.05). AR also imposed the highest stresses on the eLLIFp and these stresses increased with higher ratios (maximum stress 259MPa for ratio 0.9 during AR), yet implant failure was improbable because of the material properties of the titanium alloy used. Similarly, surrounding bone stresses were higher during AR and longer screws reduced these stresses (63MPa with a 0.6 ratio compared to 38MPa with a 0.9 ratio). Independent of screw-to-cage length ratio, eLLIFp had comparable reduction of FE and LB motion with or without posterior fixation. For eLLIFp with and without posterior fixation, torsional performance and repeatability increased with screw-to-cage length ratio. Torsional stability was comparable between stand-alone eLLIFp with high ratios (≥0.65) and posteriorly supplemented eLLIFp with low ratios (0.55). However, a threshold screw-to-cage length ratio for optimizing the clinical performance of eLLIFp cannot be prescribed. Implant stress findings reinforced torsion as the critical loading condition. Surrounding bone stress decreased as the screw length increased, indicating the benefit of using longer screws. Surgeons using eLLIFp should consider longer screw lengths based on anatomical considerations. eLLIFp cages can be used as a stand-alone device in appropriately selected patients. This avoids the morbidity and cost associated with futher supplemental posterior fixation. Surgeons using eLLIFp should consider using longer screws to optimize fixation.

Intramedullary nailing of diaphyseal femur fractures often results in reliable union, with union rates ranging from 96% to 100%. However, femoral nonunions (FNUs) can be a debilitating clinical condition for patients. The purpose of this review was to identify and characterize the predictors of nonunion after femoral midshaft fractures. A systematic search was conducted using key terms "femoral shaft non-union," "femoral diaphyseal non-union," "femoral shaft fracture," "femoral diaphysis fracture," and "femoral midshaft fracture" published before June 2024. Human studies describing risk factors associated with development of FNUs were included. Articles were excluded if not able to assess risk factors of FNUs. Data synthesis summarized outcome measures and study designs appropriately in the results. SPSS meta-analysis function was used to calculate the mean effect size estimate (MESE) and 95% confidence intervals for each outcome. This search yielded a total of 7,879 studies, and after exclusion criteria were assessed, 26 articles comprising 14,170 patients with diaphyseal femoral fractures were included. These studies included 973 fractures developing nonunions after surgical intervention. A total of 25 factors were assessed. Age (MESE = 1.33 [0.92 to 1.74]; P < 0.001) and type 2 diabetes (MESE = 1.77 [1.03 to 2.52]; P < 0.001) were significant patient-specific risk factors. Arbeitsgemeinschaft Osteosynthesefragen/Orthopaedic Trauma Association 32B (MESE = 0.94 [0.35 to 1.53]; P < 0.001) and Winquist-Hansen type 3 (MESE = 1.45 [0.63 to 2.26]; P < 0.001) were significant injury-specific factors, along with butterfly fragment size and displacement and open fractures. Open reduction (MESE = 0.80 [0.30 to 1.30]; P < 0.001) and postoperative nonsteroidal anti-inflammatory drug use (MESE = 1.17 [0.08 to 2.27]; P = 0.04) were significant surgical-specific and management-specific risk factors, along with external fixation and iatrogenic comminution. Age, diabetes, fracture classification grading, and postoperative nonsteroidal anti-inflammatory drug use were among the factors placing patients at the highest risk of femoral diaphyseal nonunions, including other patient-specific, injury-specific, surgical, and management factors. Future studies are warranted to use a prospective study design, identify diaphyseal nonunion-specific risk factors, and implement evidence-based prevention strategies. III.

<strong>Purpose.</strong> Conventional image-guided spine surgery relies on surgical trackers for real-time localization of instruments with respect to pre- or intra-operative CT images. These solutions, however, are susceptible to anatomical deformations that may occur due to patient repositioning or imparted changes during surgery. This work presents an approach that uses intraoperative tracked ultrasound (US) imaging to provide real-time verification and recovery of surgical tracking accuracy following spinal deformations. <strong>Methods.</strong> The approach combines deep-learning segmentation of the posterior vertebral cortices with a multi-step point-to- surface registration that maps reconstructed US features to the 3D CT image. The method was trained on co-registered CT and US images from 5 cadaveric specimens and validated on 2 separate specimens. The geometric accuracy of the registrations was quantified over target regions covering potential pedicle screw entry points. <strong>Results.</strong> The study confirmed the optimal level for the confidence threshold of the network output and evaluated the minimum required scan length. Vertebrae with simulated displacements were registered with 1.7 ± 0.3 mm of error. The results were robust for up to 50 mm of initial displacement. <strong>Conclusions.</strong> The solution offers a fast (real-time), portable (small device footprint), and safe (no ionizing radiation) method of tracking anatomical change during surgery. Work currently underway includes implementation of a prototype system for real-time use and evaluation of the surgical workflow with respect to factors including acquisition time, scan extent (number of vertebrae), and scan planes/trajectories.

Tibial malrotation can occur with medullary nailing of diaphyseal tibial fractures. Fibular alignment has been proposed as a surrogate for axial plane reduction intraoperatively. The purpose of this study was to determine whether fibular alignment is a reliable marker of accurate tibial rotation. Deidentified CT scans of 50 patients with normal tibial anatomy were selected. Using ImageJ software, we simulated osteotomies at three sites (proximal third, mid-diaphysis, and distal third). We overlaid adjacent CT slices and rotated them around the central axis of the tibia in 5° increments of external rotation (ER) and internal rotation (IR). At each increment, measurements of fibular overlap (%) were obtained from anteroposterior (AP) and lateral views. To simulate fixation of the fibula, we repeated rotation around the axis of the fibula with and without a simulated medullary implant in the tibia. A total of 50 patients were included. The mean age was 62 years, average BMI was 25.8, and 28 of 50 patients (56%) were male. Earliest loss of fibular contact occurred at 24° ER and 22° IR at the proximal site. Contact was lost at 26° ER and 28° IR on the AP view and 42° ER and 29° IR on the lateral view. The mean fibular contact at each 5° increment was similar for ER and IR. Fibular contact was reduced to 50% at 10 to 15° of rotation in ER and IR at all sites. Tibial canal contact was lost at 24° in both ER and IR around the fibula. With a virtual medullary implant, the mean maximal rotation was 6°. Surgeons should be aware that 20° or more of malrotation is likely present when fibular contact is lost during medullary nailing of the tibia. Greater than 50% loss of contact should raise suspicion for malrotation. A fixed fibula and medullary tibial implant theoretically preclude significant tibial malrotation.

Multiple successful strategies exist for the management of critical-sized bone defects. Depending on the location and etiology of an osseous defect, there are nuances that must be considered by the treating surgeon. The induced membrane technique and various modifications of the Ilizarov method (bone transport by distraction osteogenesis) have been the most common methods for biologic reconstruction. Despite the versatility and high union rates reported, they may not be practical for every patient. The rapid expansion of three-dimensional printing of medical devices has led to an increase in their use within orthopaedic surgery, specifically in the definitive treatment of critical bone defects. This article proposes indications and contraindications for implementation of this technology and reviews the available clinical evidence on the use of custom nonresorbable implants for the treatment of traumatic bone loss. Clinical cases are presented to illustrate the scenarios in which this approach is viable.

Pediatric patients with neuromuscular conditions often have nonorthopaedic implants that can pose a challenge for MRI acquisition and surgical planning. Treating physicians often find themselves in the position of navigating between seemingly overly risk-averse manufacturer's guidelines and an individual patient's benefits of an MRI or surgery. Most nonorthopaedic implants are compatible with MRI under specific conditions, though often require reprogramming or interrogation before and/or after the scan. For surgical procedures, the use of electrosurgical instrumentation poses a risk of electromagnetic interference and implants are thus often programmed or turned off for the procedures. Special considerations are needed for these patients to prevent device damage or malfunction, which can pose additional risk to the patient. Additional planning before surgery is necessary to ensure appropriate equipment, and staff are available to ensure patient safety.

Disparities in the access to, utilization of, and outcomes after orthopaedic surgery are a notable problem in the field that limits patients' ability to access the highest level of care and achieve optimal outcomes. Disparities exist based on numerous sociodemographic factors, with sex and race/ethnicity being two of the most well-studied factors linked to disparities in orthopaedic care. These disparities cross all subspecialties and tend to negatively affect women and racial/ethnic minorities. The increased recognition of the disparities in orthopaedic care has been paralleled by an increased recognition of the lack of diversity among orthopaedic surgeons. Although efforts are being made to improve the representation of women and underrepresented minorities among orthopaedic surgeons, the numbers, particularly of racial and ethnic minorities, show little improvement. The lack of gender and racial diversity among orthopaedic surgeons may be one of many factors related to the gender and racial disparities seen in orthopaedic care. Patients may prefer a provider that they can better identify with and that may affect care. Orthopaedic surgery as a specialty must continue to work to foster an inclusive environment and make concerted efforts to improve diversity through the recruitment of women and underrepresented minorities, among others, for the benefit of patients, surgeons, and the continued growth of the field as a whole.

With the advent of bundled care payments for spine surgery, there is increasing scrutiny on the costs and resource utilization associated with surgical care. The purpose of this study was to compare (1) the total cost of the hospital episode of care and (2) discharge destination between White, Black, and Hispanic patients receiving elective anterior cervical decompression and fusion for degenerative cervical myelopathy (DCM) in Medicare patients. The 2019 Medicare Provider Analysis and Review Limited Data Set and the 2019 Impact File were used for this project. Multivariate models were created for total cost and discharge destination, controlling for confounders found on univariate analysis. We then performed a subanalysis for differences in specific cost-center charges. There were 11,506 White (85.4%), 1,707 Black (12.7%), and 261 Hispanic (1.9%) patients identified. There were 6,447 males (47.8%) and 7,027 females (52.2%). Most patients were between 65 to 74 years of age (n = 7,101, 52.7%). The mean cost of the hospital episode was $20,919 ± 11,848. Most patients were discharged home (n = 11,584, 86.0%). Race/ethnicity was independently associated with an increased cost of care (Black: $783, Hispanic: $1,566, P = 0.001) and an increased likelihood of nonhome discharge (Black: adjusted odds ratio: 1.990, P < 0.001, Hispanic: adjusted odds ratio: 1.822, P < 0.001) compared with White patients. Compared with White patients, Black patients were charged more for accommodations ($1808), less for supplies (-$1780), and less for operating room (-$1072), whereas Hispanic patients were charged more ($3556, $7923, and $5162, respectively, P < 0.05). Black and Hispanic race/ethnicity were found to be independently associated with an increased cost of care and risk for nonhome discharge after elective anterior cervical decompression and fusion for DCM compared with White patients. The largest drivers of this disparity appear to be accommodation, medical/surgical supply, and operating room-related charges. Further analysis of these racial disparities should be performed to improve value and equity of spine care for DCM.