Outcomes and Spinopelvic Changes After Anterior Lumbar Interbody Fusion With a Novel Interbody Fusion Device: A Retrospective Study.

BACKGROUND: Interbody devices in anterior lumbar interbody fusion (ALIF) are currently a focus of innovation due to their potential to improve clinical outcomes. The purpose of the present study was to analyze complications and changes in spinopelvic parameters after ALIF with the novel Medacta MectaLIF interbody fusion device. METHODS: Patients aged 18 to 80 years who underwent multilevel ALIF using this novel implant were identified. Demographic and surgical data were collected. Patients were divided into short- and long-fusion cohorts. A comparison of outcomes between the short- and long-fusion groups was performed using the Student t test for continuous variables and Fisher's exact test and the χ2 test for categorical variables. Analysis of the pre- vs postoperative radiographic data for the entire cohort was performed using the 2-tailed Student t test. RESULTS: One hundred and eight patients met the inclusion criteria. No significant postoperative change was observed in L1-4 lumbar lordosis (LL). L1-S1 LL increased to a mean of 55.1 ± 12.8 (a mean change of 10.7 ± 14.5), and L4-S1 LL increased to a mean of 38.4 ± 8.7 (a mean increase of 7.5 ± 8.2), with pelvic incidence LL mismatch changing from 8.9 ± 15.1 to 1.1 ± 13.5 (n = 102). Related changes in sacral slope and pelvic tilt were also observed (33.0 ± 11.0 to 37.6 ± 10.9 and 19.6 ± 9.5 to 18.2 ± 9.1 [n = 103], respectively). Five patients (4.6%) experienced implant subsidence, 1 (0.9%) had implant migration, and 6 (5.6%) experienced a nonunion. There was no difference in the rates of complications associated with the novel implant in the short- and long-fusion cohorts. CONCLUSION: This novel implant achieves correction of spinopelvic parameters with minimal complications. The ability to modify the implant intraoperatively based on the patient's anatomy can help achieve maximal contact area and therefore help reduce the risk of subsidence. CLINICAL RELEVANCE: This modular implant can achieve correction of spinopelvic parameters with minimal medical and surgical complications.

Arthroscopic Lateral Retinacular-Lengthening Procedure.

Anterior knee pain is a common musculoskeletal complaint that is often due to an excessively tight lateral retinaculum, which normally plays a role in patellar tracking and stabilization. Several etiologies underlie lateral soft-tissue tightness in the knee, including lateral patellar compression syndrome, patellofemoral arthritis, patellofemoral instability, and patellofemoral pain syndrome. Stretching the lateral retinaculum through conservative treatment may be helpful, but lateral retinacular lengthening may be indicated. Since this surgical procedure has classically been performed in an open fashion, the purpose of this Technical Note is to describe an arthroscopic technique designed to limit complications, improve patient outcomes, and reduce operative and recovery times.

Intraosseous Treatment of Bone Marrow Lesions in the Knee: Surgical Technique.

Intraosseous injections of bone marrow aspirate concentrate have shown promise in the treatment of bone marrow lesions (BMLs) in the knee. With the wide-awake limited anesthesia no tourniquet (WALANT) technique, intraosseous injections can be performed with the patient under local anesthesia in the procedure room or operating room setting. This article describes 2 techniques to access the BML of interest. The "decompression route" involves drilling through the nearest cortex, and the "biologic route" involves drilling through healthy bone to promote bleeding and the introduction of healthy biologic tissue to the BML.

Antiphospholipid Syndrome Increases Postoperative Complications After Total Hip and Knee Arthroplasty.

BACKGROUND: Antiphospholipid syndrome (APS) is a systemic autoimmune condition that predisposes patients to venous thromboembolism (VTE). Although many studies have explored risk factors for VTE after joint reconstructive procedures, the impact of APS is still unclear. MATERIALS AND METHODS: A retrospective cohort study was conducted using TriNetX, a health care database that includes 442,494 patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA). Ninety-day postoperative complications and 1- and 2-year surgical complications were compared between patients with and without preexisting APS. Patients underwent propensity score matching in a 1:1 ratio based on relevant comorbidities. RESULTS: Patients undergoing THA or TKA with APS, compared with those without, had higher rates of deep venous thrombosis (hip: 9.2% vs 6.0%, odds ratio, 1.589, P=.022; knee: 10.5% vs 4.1%, odds ratio, 2.763, P<.001), pulmonary embolism (hip: 6.9% vs 3.6%, odds ratio, 1.992, P=.005; knee: 8.4% vs 3.0%, odds ratio, 2.989, P<.001), and anemia (hip: 24.8% vs 18.6%, odds ratio, 1.447, P=.004; knee: 18.5% vs 13.9%, odds ratio, 1.406, P=.007). Patients undergoing THA with APS also had higher rates of urinary tract infection (5.0% vs 2.8%, odds ratio, 1.842, P=.029) and pneumonia (3.7% vs 1.8%, odds ratio, 2.119, P=.025). APS did not impact rates of surgical complications or revision surgery. CONCLUSION: Overall, APS heightens patients' risk for complications after THA and TKA. Specific anticoagulation protocols and preoperative risk stratification should be implemented to reduce the risk of adverse events. [Orthopedics. 2024;47(5):301-307.].

Immersive Surgical Anatomy of the Far-Lateral Approach.

The far-lateral (FL) approach is a classic neurosurgical technique that enables access to the craniocervical junction, which includes the lower clivus, the anterior foramen magnum, and the first two cervical vertebrae. The FL approach also provides access to the inferior cranial nerves (i.e., CN IX, CN X, CN XI, and CN XII), distal portions of the vertebral artery (VA), and inferior basilar trunk. Recent advances in three-dimensional (3D) technology as well as dissections allow for a better understanding of the spatial relationships between anatomical landmarks and neurovascular structures encountered during neurosurgical procedures. This study aims to create a collection of volumetric models (VMs) obtained from cadaveric dissections that depict the FL approach's relevant anatomy and surgical techniques. We describe the relevant multilayer anatomy involved in the FL approach and discuss modifications of this approach as well. Five embalmed heads and two dry skulls were used to record and simulate the FL approach. Relevant steps and anatomy of the FL approach were recorded using 3D scanning technology (e.g., photogrammetry and structured light scanning) to construct high-resolution VMs. Images and VMs were generated to demonstrate major anatomical landmarks for the FL approach. The interactive models allow for clear visualization of the surgical anatomy and windows in 3D and extended reality, rendering a closer look at the nuances of the topography experienced in the laboratory. VMs can be valuable resources for surgical planning and anatomical education by accurately depicting important landmarks.

Immersive Surgical Anatomy of the Craniocervical Junction.

With the advent and increased usage of posterior, lateral, and anterior surgical approaches to the craniocervical junction (CCJ), it is essential to have a sound understanding of the osseous, ligamentous, and neurovascular layers of this region as well as their three-dimensional (3D) orientations and functional kinematics. Advances in 3D technology can be leveraged to develop a more nuanced and comprehensive understanding of the CCJ, classically depicted via dissections and sketches. As such, this study aims to illustrate - with the use of 3D technologies - the major anatomical landmarks of the CCJ in an innovative and informative way. Photogrammetry, structured light scanning, and 3D reconstruction of medical images were used to generate these high-resolution volumetric models. A clear knowledge of the critical anatomical structures and morphometrics of the CCJ is crucial for the diagnosis, classification, and treatment of pathologies in this transitional region.

Anterior cervical discectomy and fusion performed using structural allograft or polyetheretherketone: pseudarthrosis and revision surgery rates with minimum 2-year follow-up.

OBJECTIVE: Both structural allograft and PEEK have been used for anterior cervical discectomy and fusion (ACDF). There are reports that PEEK has a higher pseudarthrosis rate than structural allograft. The authors compared pseudarthrosis, revision, subsidence, and loss of lordosis rates in patients with PEEK and structural allograft. METHODS: The authors performed a retrospective review of patients who were treated with ACDF at their hospital between 2005 and 2017. Inclusion criteria were adult patients with either PEEK or structural allograft, anterior plate fixation, and a minimum 2-year follow-up. Exclusion criteria were hybrid PEEK and allograft cases, additional posterior surgery, adjacent corpectomies, infection, tumor, stand-alone or integrated screw and cage devices, bone morphogenetic protein use, or lack of a minimum 2-year follow-up. Demographic variables, number of treated levels, interbody type (PEEK cage vs structural allograft), graft packing material, pseudarthrosis rates, revision surgery rates, subsidence, and cervical lordosis changes were collected. These data were analyzed by Pearson's chi-square test (or Fisher's exact test, according to the sample size and expected value) and Student t-test. RESULTS: A total of 168 patients (264 levels total, mean follow-up time 39.5 ± 24.0 months) were analyzed. Sixty-one patients had PEEK, and 107 patients had structural allograft. Pseudarthrosis rates for 1-level fusions were 5.4% (PEEK) and 3.4% (allograft) (p > 0.05); 2-level fusions were 7.1% (PEEK) and 8.1% (allograft) (p > 0.05); and ≥ 3-level fusions were 10% (PEEK) and 11.1% (allograft) (p > 0.05). There was no statistical difference in the subsidence magnitude between PEEK and allograft in 1-, 2-, and ≥ 3-level ACDF (p > 0.05). Postoperative lordosis loss was not different between cohorts for 1- and 2-level surgeries. CONCLUSIONS: In 1- and 2-level ACDF with plating involving the same number of fusion levels, there was no statistically significant difference in the pseudarthrosis rate, revision surgery rate, subsidence, and lordosis loss between PEEK cages and structural allograft.

Speciation Theory of Carcinogenesis Explains Karyotypic Individuality and Long Latencies of Cancers.

It has been known for over 100 years that cancers have individual karyotypes and arise only years to decades after initiating carcinogens. However, there is still no coherent theory to explain these definitive characteristics of cancer. The prevailing mutation theory holds that cancers are late because the primary cell must accumulate 3⁻8 causative mutations to become carcinogenic and that mutations, which induce chromosomal instability (CIN), generate the individual karyotypes of cancers. However, since there is still no proven set of mutations that transforms a normal to a cancer cell, we have recently advanced the theory that carcinogenesis is a form of speciation. This theory predicts carcinogens initiate cancer by inducing aneuploidy, which automatically unbalances thousands of genes and thus catalyzes chain-reactions of progressive aneuploidizations. Over time, these aneuploidizations have two endpoints, either non-viable karyotypes or very rarely karyotypes of new autonomous and immortal cancers. Cancer karyotypes are immortalized despite destabilizing congenital aneuploidy by clonal selections for autonomy-similar to those of conventional species. This theory predicts that the very low probability of converting the karyotype of a normal cell to that of a new autonomous cancer species by random aneuploidizations is the reason for the karyotypic individuality of new cancers and for the long latencies from carcinogens to cancers. In testing this theory, we observed: (1) Addition of mutagenic and non-mutagenic carcinogens to normal human and rat cells generated progressive aneuploidizations months before neoplastic transformation. (2) Sub-cloning of a neoplastic rat clone revealed heritable individual karyotypes, rather than the non-heritable karyotypes predicted by the CIN theory. (3) Analyses of neoplastic and preneoplastic karyotypes unexpectedly identified karyotypes with sets of 3⁻11 new marker chromosomes without detectable intermediates, consistent with single-step origins. We conclude that the speciation theory explains logically the long latencies from carcinogen exposure and the individuality of cancers. In addition, the theory supports the single-step origins of cancers, because karyotypic autonomy is all-or-nothing. Accordingly, we propose that preneoplastic aneuploidy and clonal neoplastic karyotypes provide more reliable therapeutic indications than current analyses of thousands of mutations.