Performance Outcomes and Return-to-Sport Rate of National Hockey League Athletes Vary After Common Orthopedic Surgical Procedures.

OBJECTIVE: Evaluate performance-based outcomes and return-to-sport rate in National Hockey League (NHL) athletes. DESIGN: Retrospective cohort study. SETTING: Public records. No direct patient care was provided. PARTICIPANTS: National Hockey League athletes who underwent different orthopedic procedures were identified using public records. Three hundred thirty-seven athletes met inclusion criteria. INDEPENDENT VARIABLES: Common orthopedic surgical procedures in NHL athletes. MAIN OUTCOME MEASURES: Return-to-play and preoperative and postoperative performance measures were collected to calculate a position-specific performance score. Short-term and medium-term outcomes were defined as 1 and 2 to 3 seasons after surgery, respectively. RESULTS: Three hundred seven athletes (92.6%) successfully returned to play. The number of games played during the first season after surgery compared with baseline was significantly decreased for hip arthroscopy (HA), noninstability shoulder arthroscopy (ie, shoulder arthroscopy procedure to address pathology other than shoulder instability), knee arthroscopy, and sports hernia repair (P = 0.002, 0.009, 0.03, and 0.01, respectively). The number of games played for seasons 2 and 3 after surgery was significantly decreased for both HA and noninstability shoulder arthroscopy (P = 0.01 and 0.001, respectively). Short-term postoperative performance scores were significantly decreased for HA, noninstability shoulder arthroscopy, and anterior cruciate ligament reconstruction (P = 0.00004, 0.02, and 0.02, respectively) while medium-term scores were significantly decreased for HA only (P = 0.009). CONCLUSIONS: National Hockey League athletes return to play at a high rate after common orthopedic surgeries. However, certain procedures portend poorer performance scores and game participation than others. In particular, HA and noninstability shoulder arthroscopy have the greatest negative effect on NHL careers after surgery.

Augmented reality and artificial intelligence-assisted surgical navigation: Technique and cadaveric feasibility study.

PURPOSE: Augmented reality-based image overlay of virtual bony spine anatomy can be projected onto real spinal anatomy using computer tomography-generated DICOM images acquired intraoperatively. The aim of the study was to develop a technique and assess the accuracy and feasibility of lumbar vertebrae pedicle instrumentation using augmented reality-assisted surgical navigation. SUBJECTS AND METHODS: An augmented reality and artificial intelligence (ARAI)-assisted surgical navigation system was developed. The system consists of a display system which hovers over the surgical field and projects three-dimensional (3D) medical images corresponding with the patient's anatomy. The system was registered to the cadaveric spine using an optical tracker and arrays with reflective markers. The virtual image overlay from the ARAI system was compared to 3D generated images from intraoperative scans and used to percutaneously navigate a probe to the cortex at the corresponding pedicle starting point. Intraoperative scan was used to confirm the probe position. Virtual probe placement was compared to the actual probe position in the bone to determine the accuracy of the navigation system. RESULTS: Four cadaveric thoracolumbar spines were used. The navigated probes were correctly placed in all attempted levels (n = 24 levels), defined as Zdichavsky type 1a, Ravi type I, and Gertzbein type 0. The virtual overlay image corresponded to the 3D generated image in all the tested levels. CONCLUSIONS: The ARAI surgical navigation system correctly and accurately identified the starting points at all the attempted levels. The virtual anatomy image overlay precisely corresponded to the actual anatomy in all the tested scenarios. This technology may lead more uniform outcomes between surgeons and decrease minimally invasive spine surgery learning curves.

3D-Printed Ceramic-Demineralized Bone Matrix Hyperelastic Bone Composite Scaffolds for Spinal Fusion.

Although numerous spinal biologics are commercially available, a cost-effective and safe bone graft substitute material for spine fusion has yet to be proven. In this study, "3D-Paints" containing varying volumetric ratios of hydroxyapatite (HA) and human demineralized bone matrix (DBM) in a poly(lactide-co-glycolide) elastomer were three-dimensional (3D) printed into scaffolds to promote osteointegration in rats, with an end goal of spine fusion without the need for recombinant growth factor. Spine fusion was evaluated by manual palpation, and osteointegration and de novo bone formation within scaffold struts were evaluated by laboratory and synchrotron microcomputed tomography and histology. The 3:1 HA:DBM composite achieved the highest mean fusion score and fusion rate (92%), which was significantly greater than the 3D printed DBM-only scaffold (42%). New bone was identified extending from the host transverse processes into the scaffold macropores, and osteointegration scores correlated with successful fusion. Strikingly, the combination of HA and DBM resulted in the growth of bone-like spicules within the DBM particles inside scaffold struts. These spicules were not observed in DBM-only scaffolds, suggesting that de novo spicule formation requires both HA and DBM. Collectively, our work suggests that this recombinant growth factor-free composite shows promise to overcome the limitations of currently used bone graft substitutes for spine fusion. Impact Statement Currently, there exists a no safe, yet highly effective, bone graft substitute that is well accepted for use in spine fusion procedures. With this work, we show that a three-dimensional printed scaffold containing osteoconductive hydroxyapatite and osteoinductive demineralized bone matrix that promotes new bone spicule formation, osteointegration, and successful fusion (stabilization) when implemented in a preclinical model of spine fusion. Our study suggests that this material shows promise as a recombinant growth factor-free bone graft substitute that could safely promote high rates of successful fusion and improve patient care.

The Variability of Lumbar Facet Joint Synovial Cyst Recurrence Requiring Revision Surgery After Decompression-only and Decompression/Fusion.

STUDY DESIGN: This is a retrospective study. OBJECTIVE: The objective of this study was to evaluate lumbar spine synovial cyst recurrence rates of decompression-alone versus decompression/fusion procedures. BACKGROUND: Improvements in imaging modalities allow for increased diagnosis and surgical treatment of symptomatic spinal juxtafacet synovial cysts. Conservative management may be used as a first-line management strategy, however rarely provides durable, effective relief of symptoms. Surgical treatment of spinal synovial cysts ranges from decompression and cyst excision to decompression with fusion procedures. Decompression procedures alone have a higher risk of recurrence of spinal synovial cysts. METHODS: We retrospectively reviewed 87 patients undergoing surgical treatment of lumbar spinal juxtafacet synovial cysts as a single institution over 20 years. Surgical treatment consisted of either decompression versus decompression/fusion procedures. Preoperative symptoms included back pain, radiculopathy, motor deficits, or sensory deficits. The incidence of recurrence of spinal synovial cysts at the same-site or differing sites was compared between 2 categories of surgical treatment. Revision surgical procedure rates were also evaluated. RESULTS: A total of 55 (63%) patients were treated with an index decompression-only procedure for the lumbar spinal synovial cyst compared with 32 (37%) patients treated with an index decompression and fusion procedure. Fifty-eight (68%) of the lumbar spinal cysts occurred at the L4-L5 level. There were 10 (11.5%) spinal synovial cyst recurrences in the decompression-only group, and 0 recurrences in the decompression/fusion group. Revision decompression procedures were performed in 4 of the 10 (4.6%) recurrences, and 6 of 10 (6.9%) recurrences had subsequent decompression and fusion surgery. The mean time to recurrence was 23.9±17.3 months. The mean length of follow-up was 65.1±48.6 months. Both recurrence and nonrecurrence cohorts had significant symptomatic improvement using Odom criteria. CONCLUSIONS: Decompression and cyst excision was the more common surgical treatment of lumbar spinal synovial cysts compared with decompression/fusion procedure in our study. The rate of synovial cyst recurrence and revision surgery in patients undergoing index decompression was relatively low and comparable to current literature. Symptomatic improvement of patients undergoing decompression versus decompression/fusion was similar in our study. Although the fusion may be required for the extent of pathology or coexisting instability, decompression and excision of spinal synovial cysts provide durable, effective treatment with a known, appropriate risk of recurrence and subsequent revision surgery.

Aryl Hydrocarbon Receptor Antagonists Mitigate the Effects of Dioxin on Critical Cellular Functions in Differentiating Human Osteoblast-Like Cells.

The inhibition of bone healing in humans is a well-established effect associated with cigarette smoking, but the underlying mechanisms are still unclear. Recent work using animal cell lines have implicated the aryl hydrocarbon receptor (AhR) as a mediator of the anti-osteogenic effects of cigarette smoke, but the complexity of cigarette smoke mixtures makes understanding the mechanisms of action a major challenge. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD, dioxin) is a high-affinity AhR ligand that is frequently used to investigate biological processes impacted by AhR activation. Since there are dozens of AhR ligands present in cigarette smoke, we utilized dioxin as a prototype ligand to activate the receptor and explore its effects on pro-osteogenic biomarkers and other factors critical to osteogenesis using a human osteoblast-like cell line. We also explored the capacity for AhR antagonists to protect against dioxin action in this context. We found dioxin to inhibit osteogenic differentiation, whereas co-treatment with various AhR antagonists protected against dioxin action. Dioxin also negatively impacted cell adhesion with a corresponding reduction in the expression of integrin and cadherin proteins, which are known to be involved in this process. Similarly, the dioxin-mediated inhibition of cell migration correlated with reduced expression of the chemokine receptor CXCR4 and its ligand, CXCL12, and co-treatment with antagonists restored migratory capacity. Our results suggest that AhR activation may play a role in the bone regenerative response in humans exposed to AhR activators, such as those present in cigarette smoke. Given the similarity of our results using a human cell line to previous work done in murine cells, animal models may yield data relevant to the human setting. In addition, the AhR may represent a potential therapeutic target for orthopedic patients who smoke cigarettes, or those who are exposed to secondhand smoke or other environmental sources of aryl hydrocarbons.

Sulfated glycopeptide nanostructures for multipotent protein activation.

Biological systems have evolved to utilize numerous proteins with capacity to bind polysaccharides for the purpose of optimizing their function. A well-known subset of these proteins with binding domains for the highly diverse sulfated polysaccharides are important growth factors involved in biological development and tissue repair. We report here on supramolecular sulfated glycopeptide nanostructures, which display a trisulfated monosaccharide on their surfaces and bind five critical proteins with different polysaccharide-binding domains. Binding does not disrupt the filamentous shape of the nanostructures or their internal ß-sheet backbone, but must involve accessible adaptive configurations to interact with such different proteins. The glycopeptide nanostructures amplified signalling of bone morphogenetic protein 2 significantly more than the natural sulfated polysaccharide heparin, and promoted regeneration of bone in the spine with a protein dose that is 100-fold lower than that required in the animal model. These highly bioactive nanostructures may enable many therapies in the future involving proteins.

Environmental Factors Impacting Bone-Relevant Chemokines.

Chemokines play an important role in normal bone physiology and the pathophysiology of many bone diseases. The recent increased focus on the individual roles of this class of proteins in the context of bone has shown that members of the two major chemokine subfamilies-CC and CXC-support or promote the formation of new bone and the remodeling of existing bone in response to a myriad of stimuli. These chemotactic molecules are crucial in orchestrating appropriate cellular homing, osteoblastogenesis, and osteoclastogenesis during normal bone repair. Bone healing is a complex cascade of carefully regulated processes, including inflammation, progenitor cell recruitment, differentiation, and remodeling. The extensive role of chemokines in these processes and the known links between environmental contaminants and chemokine expression/activity leaves ample opportunity for disruption of bone healing by environmental factors. However, despite increased clinical awareness, the potential impact of many of these environmental factors on bone-related chemokines is still ill defined. A great deal of focus has been placed on environmental exposure to various endocrine disruptors (bisphenol A, phthalate esters, etc.), volatile organic compounds, dioxins, and heavy metals, though mainly in other tissues. Awareness of the impact of other less well-studied bone toxicants, such as fluoride, mold and fungal toxins, asbestos, and chlorine, is also reviewed. In many cases, the literature on these toxins in osteogenic models is lacking. However, research focused on their effects in other tissues and cell lines provides clues for where future resources could be best utilized. This review aims to serve as a current and exhaustive resource detailing the known links between several classes of high-interest environmental pollutants and their interaction with the chemokines relevant to bone healing.

Cost Effectiveness of a Fast-Track Protocol for Urgent Laparoscopic Cholecystectomies and Appendectomies.

BACKGROUND: Fast-track protocols (FTPs) are used to decrease length of stay (LOS) and hospital costs for elective outpatient procedures. Few institutions have implemented FTP for urgent procedures such as laparoscopic cholecystectomy (LC) and laparoscopic appendectomy (LA). STUDY DESIGN: This is a retrospective single-institution cohort study including all patients undergoing urgent LC or LA between July 1, 2010 and May 1, 2013. Exclusion criteria included conversion to open procedure, perforated appendicitis, or procedure related to intra-abdominal injury. Analysis included a comparison of the three study groups: (1) before (PRE) and after (POST) implementation of the fast-track protocol (FTP), (2) fast-track cohort (FT) and non-fast-track cohort (NFT), and (3) those completing the fast-track pathway (FT-C) and those who began but failed to complete the pathway (FT-F). RESULTS: There were significant reductions in LOS between all study groups compared: between PRE (n = 256) and POST (n = 472) cohorts by half a day (2.0 vs. 1.5 days, p < 0.02); between FT and NFT (0.68 vs. 1.82 days, p < 0.01); and FT-C and FT-F (0.49 vs. 1.05 days, p < 0.01). Total hospital charges were significantly reduced in FT compared with NFT ($22,347 vs. $30,868, p < 0.01) with an average savings of $8521. Total hospital charges were decreased in the FT-C compared with FT-F cohorts ($21,971 vs. $22,939, p = 0.3) with an average savings of $968. Readmissions, complications, and satisfaction were similar for all comparison groups. CONCLUSIONS: FTPs for urgent appendectomies and cholecystectomies can significantly reduce hospital costs by reducing LOS without compromising patient outcomes.