Surgical Technology International
35th Edition
Contains 55 peer-reviewed articles featuring the latest advances in surgical techniques and technologies.
456 pages
Nov 2019 - ISSN:1090-3941
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both electronic and print versions
Orthopaedic Surgery
Outcomes of Augmented Dual Mobility Acetabular Cups
Remi Philippot, MD, PhD, Professor of Surgery, Pierre-Henry Vermorel, MD, Resident, Bertrand Boyer, MD, PhD, Doctor of Surgery , Frederic Farizon, MD, Professor of Surgery , Thomas Neri, MD, PhD, Doctor of Surgery, Vincent Genestoux, MD, Resident, University Hospital Centre of Saint-Etienne, Saint-Etienne, France, University Lyon - University Jean Monnet, Saint Etienne, France, Emmanuel Baulot, MD, Professor of Surgery, Philibert Alixant, MD, Resident, Pierre Martz, MD, PhD, Doctor of Surgery, Hopital Universitaire François Mitterand, Dijon, France
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Introduction: Total hip arthroplasty (THA) in patients with acetabular bone defects is associated with a high risk of dislocation and aseptic loosening. No studies to date have examined the use of uncemented and augmented dual mobility cups (DMC) in patients with acetabular defects. We hypothesized that the use of augmented DMC under these conditions would reduce the dislocation rate and lead to satisfactory bone integration in the medium term despite acetabular bone defects.
Materials and methods: This continuous multicenter study included all cases of augmented DMC performed between 2010 and 2017 in patients with acetabular bone loss (Paprosky 2A: 46%, 2B: 32%, 2C: 15% and 3A: 6%). The indications for implantation were revisions for cup aseptic loosening (AL) (n=45), femoral stem AL (n=3), bipolar AL (n=11), septic loosening (n=10), periprosthetic fracture (n=5), chronic dislocation (n=4), intraprosthetic dislocation (n=2), cup impingement (n=1), primary posttraumatic arthroplasty (n=8), and acetabular dysplasia (n=4). The clinical assessment consisted of the Harris hip score (HHS) and Merle d’Aubigné Postel score (MDP), along with preoperative and final follow-up radiographs. The primary endpoint was surgical revision for aseptic acetabular loosening or the occurrence of dislocation.
Results: Overall, 93 patients were reviewed at a mean follow-up of 5.3 ± 2.3 years [0, 10]. As of the last follow-up, the acetabular cup had been changed in five cases: 3 AL (3.2%) and 2 infections (2.1%). Thus the overall survivorship of the cup was 94.6% and the survivorship for AL was 96.8%. Three patients (3%) suffered a dislocation. At the last follow-up visit, the mean MDP and HHS scores were 14.75 and 72.15, respectively, which reflected significant improvements relative to the preoperative scores (p < 0.05).
Conclusion: Use of an uncemented and augmented DMC in cases of acetabular bone defect leads to satisfactory medium-term results with low dislocation and loosening rates. We recommend its use in these cases.
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Current Concepts in Osteoarthritis of the Ankle: Review
Hannah Khlopas, DPM, Resident , Beaumont Hospital, Wayne, Michigan, Anton Khlopas, MD, Resident , Linsen T. Samuel, MD, MBA, Clinical Research Fellow, Erin Ohliger, MD, Resident, Assem A. Sultan, MD, Resident, Morad Chughtai, MD, Resident, Cleveland Clinic, Cleveland, Ohio, Michael A. Mont, MD, Vice President of Strategic Initiatives for Orthopaedic Surgery , Chief of Joint Reconstruction, Northwell Health and Lenox Hill Hospital, New York, New York
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Ankle osteoarthritis constitutes a large burden to society and is a leading cause of chronic disability in the United States. Most commonly, it is post-traumatic, occurs in younger individuals, and is associated with obesity. This entity presents similarly to osteoarthritis of the other joints, with the typical nonspecific symptoms of stiffness, swelling, and pain. Radiographic investigation includes four weight-bearing standard views: antero-posterior and lateral foot, mortise view of the ankle, and a specialized view of the hindfoot. In this review, we covered epidemiology, anatomy and biomechanics, etiology, pathology, differential diagnoses, symptoms, physical examination, appropriate radiological investigation, as well as current treatment options and algorithms. Non-operative treatment options include weight loss, physical therapy, bracing, orthoses, pharmacologic treatments, corticosteroid injections, viscosupplementation, and biologic modalities. Viscosupplementation with hyaluronic acid has the most evidence-based support and has been shown to be safe and efficacious. For patients who have moderate to severe disease, surgery may be indicated. However, current surgical options are either associated with high rates of complications or restrict ankle range of motion (ROM). Early stages of the ankle osteoarthritis should be treated with the above-mentioned non-surgical methods, and once the disease progresses, surgical options can be utilized.
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Mid-Term Results of Modular Tapered Femoral Stems in Revision Total Hip Arthroplasty
Kojo A. Marfo, MD, Fellow, Keith R. Berend, MD, Vice President, Michael J. Morris, MD, Orthopedic Surgeon, Joanne B. Adams, BFA, CMI, Research Director, Adolph V. Lombardi, Jr., MD, FACS, President, Joint Implant Surgeons, Inc., New Albany, Ohio, White Fence Surgical Suites, New Albany, Ohio, Mount Carmel Health System, Columbus, Ohio, The Ohio State University, Wexner Medical Center, Columbus, Ohio
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Background: In revision total hip arthroplasty (THA), modular femoral components aid the surgeon in reconstructing joints compromised by loss of bone and soft-tissue integrity, providing customization to address bony deficits, deformity, limb length, and offset challenges. The purpose of this study was to review the survival and outcomes at minimum five-year follow up of patients who underwent revision THA at our center with a single modular femoral revision hip system offering a wide range of proximal body and distal stem geometries and sizing options.
Materials and Methods: A query of our practice arthroplasty registry revealed 66 consented patients (69 hips) who underwent revision THA using a modular femoral stem between December 2009 and July 2013 with minimum five-year follow up. There were 35 men (53%) and 31 women (47%). Mean age was 65.2 years (range, 36–87). Etiology for index revision was 32 aseptic loosening, 20 infection, nine periprosthetic fracture, three nonunion of internal fixation, three instability, one stem breakage, and one metal complication.
Results: Mean follow up was 6.3 years (range, 5–9). Harris Hip Scores improved from a mean of 45.4 preoperatively to 72.0 at most recent evaluations. There have been four re-revisions of the femoral stem: one infection, two periprosthetic femoral fracture, and one (proximal segment only) for instability. Radiographic assessment revealed satisfactory position, fixation, and alignment in all hips. Radiographic subsidence of 6–10mm occurred in four (none revised), and none had subsidence > 10mm. There were no modular junction failures. Kaplan-Meier survival to endpoint of femoral revision was 93.3% (95% CI ±3.3%) at 8.7 years.
Conclusions: The minimum five-year results of this modular THA revision system are promising, with low rates of aseptic failure, minimal subsidence, and no modular junction failures. While there may be roles for the use of non-modular revision stems, the mid-term clinical results in this cohort of patients was found to be acceptable.
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Pain Management Strategies To Reduce Opioid Use Following Total Knee Arthroplasty
Michael J. Derogatis, MS, Medical Student, Nipun Sodhi, MD, Research Fellow, Joseph O. Ehiorobo, MD, Research Fellow, Michael A. Mont, MD, System Chief of Joint Reconstruction, Vice President, Strategic Initiatives, Lenox Hill Hospital, Northwell Health, New York, New York , Hiba K. Anis, MD, Research Fellow, Cleveland Clinic, Cleveland, Ohio , Anil Bhave, PT, Clinical Director , Orthopaedic Rehabilitation, Rubin Institute of Advanced Orthopaedics, Sinai Hospital, Baltimore, Maryland
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Introduction: Due to the rising concern regarding excessive opioid use, several alternative pain control options have been developed for total knee arthroplasty (TKA). Therefore, the purpose of this article was to review non-narcotic treatments to manage pain after TKA. Specifically, we evaluated: 1) acetaminophen; 2) cyclooxygenase-2 (cox-2) inhibitors; 3) gabapentinoids; 4) dexmedetomidine, 5) nerve blocks; 6) local analgesic infiltration; 7) transcutaneous electrical nerve stimulation (TENS); and 8) perioperative bracing.
Materials and Methods: A literature search was conducted using the PubMed and EBSCO host electronic databases. All available studies between 1998 and 2018 were evaluated. Searches were performed using the following terms: total knee arthroplasty (title), acetaminophen (title), cyclooxygenase-2 inhibitors (title), gabapentinoids (title), nerve blocks (title), local analgesic infiltration (title), transcutaneous electrical nerve stimulation (title), knee (title), postoperative outcome (title), opioids (title), analgesics (title), alternative (title), heroin (title), chronic pain (title), opioid overdose (title), and cost (title). After full-text analysis of 273 reports that satisfied the search criteria, 58 studies were included in this review.
Results: There is conflicting evidence on acetaminophen and gabapentinoids, with some studies reporting opioid use reduction with their use; whereas, others found no difference. Cox-2 inhibitors can potentially reduce opioid requirements and improve pain scores following TKA; however, they are associated with several side effects. Dexmedetomidine has been associated with reduced postoperative opioid consumption, but it has limited applications as it is associated with several major side effects. Neuraxial anesthesia can potentially help control postoperative pain; however, there is a limited effective window and identifying the specific nerve can be challenging. Local infiltrating analgesia have been found to help relieve pain in the early postoperative period. Multiple studies have identified substantial reductions in pain with knee braces. The non-invasive and non-pharmacologic nature of this treatment option makes it very safe and effective for the generalized TKA population.
Conclusion: The optimal solution for postoperative TKA pain management has yet to be determined. Although several options exist, many of them have been associated with adverse effects limiting their generalizability. Knee braces, however, have been identified as one potentially successful option. Importantly, knee braces are safe for the majority of patients and should be widely recommended for patient use.
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Validation of the Anterior Cruciate Ligament (ACL) Module of the VirtaMed Virtual Reality Arthroscopy Trainer
Jop Antonis, MD, Orthopaedic Surgeon, Shayan Bahadori, BEng (Hons), MSc, Project Manager, Tikki Immins, BSc (Hons), MSc, Research Development Manager, Orthopaedic Research Institute, Bournemouth University, Bournemouth, UK, Kieran Gallagher, Mbbs, BSc (Hons), FRCS (Tr&Orth), Consultant Orthopaedic, Hip Trauma &, Reconstruction Surgeon, Thomas W. Wainwright, PgDip, PgCert, Bsc(Hons), MCSP, Deputy Head, Orthopaedic Research Institute, Robert Middleton, MA, MBBchir, FRICS, FRICS, (Orth), CCST, Consultant Orthopaedic Surgeon, Head, Orthopaedic Research Institute, Bournemouth University, Bournemouth, UK, The Royal Bournemouth and Christchurch Hospitals , NHS Foundation Trust, Bournemouth, UK
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Objective: To assess the newly developed anterior cruciate ligament (ACL) module of a VR arthroscopy trainer for content, construct and face validity.
Design: Participants were divided into expert and novice groups based on their experience with ACL arthroscopy. Participants were given a standardized introduction, shown a video on how to use the simulator, and performed a 5-minute partial meniscectomy task, to familiarise them with the equipment. Participants then undertook an ACL reconstruction task. On completion, the simulator produced a summary of performance metrics for the following domains: Operation Time, ACL Reconstruction, Safety, Economy, Detailed Visualization and Total Score. A 7-point Likert scale questionnaire was used to assess the face and content validity of the simulator.
Participants: Twenty one participants from a hospital orthopaedic department were recruited. Five were classified as expert, 16 as novice.
Results: An independent Mann-Whitney U test showed no significant differences between experts and novices for any of the domains. Questionnaire responses regarding hand-eye coordination, camera navigation training, diagnostic training, tunnel preparation and overall training capacity were scored as either ‘good’ or ‘excellent’ by more than 70% of the participants. All responses regarding the ‘graft insertion task’ scored low.
Conclusion: The current iteration of the VR knee ArthroS™ simulator (VirtaMed AG, Zurich, Switzerland) is promising, but requires further development of the ACL procedure, in particular the graft insertion task, before it can be considered as part of training curricula.
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Patient-Reported Outcomes After Arthroscopic Shoulder Surgery With Interscalene Brachial Plexus Nerve Block Using Liposomal Bupivacaine: A Prospective Observational Study
Elizabeth Ford, BA, Lead Orthopedic Research Coordinator, Sundeep Saini, DO, Doctor of Osteopathic Medicine, Sean McMillan, DO, FAOAO, Chief of Orthopedics, Patrick Szukics, DO, Doctor of Osteopathic Medicine, Andrew A. Assiamah, MD, Doctor of Medicine, Lourdes Medical Center of Burlington County, Willingboro, New Jersey, Rowan University School of Osteopathic Medicine, Stratford, New Jersey
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Background: Interscalene brachial plexus nerve blocks (ISBPNBs) are commonly used to mitigate postsurgical pain after shoulder surgery.
Materials and Methods: We performed a prospective observational study in 57 consecutive adult patients undergoing arthroscopic shoulder surgery with an ultrasound-guided ISBPNB using liposomal bupivacaine (LB; 133mg/10ml) mixed with 0.5% bupivacaine (10ml). All patients received prescriptions for 1000mg of oral acetaminophen and 10 5mg oxycodone tablets upon discharge.
Results: Post-discharge telephone surveys revealed that mean (standard deviation [SD]) patient-reported motor and sensory recovery times after surgery were 26.8 (3.2) and 34.0 (3.6) hours, respectively. The average (SD) visual analog scale pain score was 5.1 (3.1) at day two post-surgery. The estimated opioid utilization rate at day seven post-surgery was 21% of the prescribed opioid tablets.
Conclusions: Our real-world observational findings suggest that multimodal postsurgical pain control using single-shot, ultrasound-guided ISBPNB with LB and postsurgical acetaminophen provides favorable pain control and limited need for postsurgical opioid rescue for seven days after shoulder surgery.
Aneurysmal Bone Cyst: A Review of Management
Francesco Muratori, MD, Specialist Orthopedics and Traumatology, Anna Rosa Rizzo, MD, Resident Orthopedics and Traumatology, Giovanni Beltrami, Specialist Orthopedics and Traumatology, Domenico Andrea Campanacci, MD, Professor Orthopedics and Traumatology, Reconstructive Surgery, Azienda Ospedaliero Universitaria Careggi, Firenze, Italy, Nicola Mondanelli, MD, PhD, Specialist Orthopedics and Traumatology , Stefano Giannotti, MD, Professor Orthopedics and Traumatology, University of Siena, Siena, Italy , Azienda Ospedaliero Universitaria Senese, Siena, Italy, Rodolfo Capanna, MD, Professor Orthopedics and Traumatology, University of Pisa, Pisa, Italy
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Aneurysmal bone cyst is a rare lesion that is most often found in young adults and children. It can have an unpredictable behavior, with a high recurrence rate after treatment. Treatment is based on personal and institutional experience and preferences. Standard treatment consists of curettage (manual + motorized high-speed burr) plus local adjuvants and bone grafting to fill the void. In anatomical locations that are difficult to reach surgically, percutaneous procedures (injection of sclerosant agents, radiofrequency thermal ablation (RFTA)) or selective arterial embolization (SAE) are used. Medical management with bisphosphonates (BPs) or denosumab has also been advocated. Minimally invasive surgical procedures such as “curopsy” and percutaneous demineralized bone matrix (DBM) and/or autologous bone marrow concentrate (BMC) grafting have also been proposed. SAE is used as a pre-operative procedure to reduce intra-operative bleeding in the case of large lesions and as primary treatment for spinal lesions. The purpose of this review is to present currently available options for the management of aneurysmal bone cyst.
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Modern Total Knee Arthroplasty (TKA):With Or Without a Tourniquet?
Sina Nicolaiciuc, Cand. Med., Technical University Munich, Munich, Germany, Philipp Probst, MSc. Statistics, Scientific Assistant, Institute for Medical Information Processing, Ludwig-Maximilians-University Munich, Munich, Germany, Rüdiger von Eisenhart-Rothe, MD, Professor of Orthopedic Surgery, Director, Rechts der Isar Hospital, Technical University of Munich, Munich, Germany, Rainer Burgkart, MD, Professor of Orthopedic Surgery, Head of Orthopedic Research and Teaching, Rechts der Isar Hospital, Technical University of Munich, Munich, Germany, Robert Hube, MD, Professor of Orthopedic Surgery, Charité -University Medicine Berlin, Director - Center of Joint Replacement, OCM/SANA Campus Munich, Munich, Germany
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BACKGROUND: Since arthritis of the knee is one of the most common pathologies in industrialized nations, there has been a growing interest in fast-track total knee arthroplasty (TKA). However, while one of the main concerns is the role of a tourniquet, the available data are inconclusive.
AIM: This study sought to assess the link between postoperative outcomes and use of a tourniquet in TKA. Our goal was to determine whether it is justified to forego tourniquet use as indicated by the fast-track concept.
METHODS: The participants (n = 108) in this retrospective, non-randomized study were assigned into two groups after they satisfied the inclusion criteria: primary gonarthrosis or secondary gonarthrosis without previous arthrotomy. TKA was performed without (Group I, n = 55) or with (Group II, n = 53) a tourniquet. The postoperative outcome was evaluated in terms of postoperative pain, based on a numeric rating scale (NRS) and the need for pain medication, and postoperative function, based on range of motion (ROM) and walking tests.
RESULTS: Overall, no significant correlations were observed between tourniquet use and postoperative pain according to the NRS. Group I required less oxycodone, but more non-opioids. There was no significant difference in the improvement in pre- to postoperative ROM with regard to tourniquet use. The final walking distance was significantly longer in Group I.
CONCLUSIONS: These results suggest that there is no strongly significant link between the postoperative outcome and the use of a tourniquet. However, further studies will be needed to determine whether a tourniquet may have some other impact on TKA.
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Anterior Cruciate Ligament Repair in a Professional Soccer Player Using Internal Brace Ligament Augmentation: A Case Report Focusing on Rehabilitation
Victoria McIntyre, MSc, Physiotherapist, University of Salford, Salford, England, Graeme P Hopper, MBChB, MSc, MRCS, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, Gordon M Mackay MD, FRCS (Orth), Professor, University of Stirling, Stirling, Scotland
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Background: Anterior cruciate ligament (ACL) reconstruction with hamstring or patellar tendon autograft has been the gold standard for the operative treatment of an ACL rupture for many years. Repair with Internal Brace Ligament Augmentation (IBLA) is a new technique that uses ultra-high strength tape (FiberTape, Arthrex, Naples, FL, USA) to bridge the ligament. This technique reinforces the ligament as a secondary stabiliser, encouraging natural healing of the ligament by protecting it during the healing phase and supporting early mobilisation.
Case Description: This retrospective case report focuses on the rehabilitation of a 21-year-old male professional soccer player who ruptured his ACL in a contact injury whilst playing a competitive game. He underwent ACL repair with IBLA two weeks following injury. The six-month rehabilitation programme consisted of gradual progressions for mobility, proprioception, strengthening, cardiovascular maintenance and running in conjunction with physiotherapy to assist with the maintenance of soft tissue quality, pain management and control of oedema.
Results: After completing the rehabilitation programme, the patient returned to unrestricted sporting activity within six months. At 18-month follow-up, the patient continues to play at the same competitive level without any issues.
Conclusion: This rehabilitation programme after ACL repair with IBLA successfully enabled a professional soccer player to return to his pre-injury playing level.
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Validation of Gender and Height Predicting Femoral Size of the Oxford® Unicondylar Knee Arthroplasty: A Simplified Method
David A. Crawford, MD, Associate , Joint Implant Surgeons, Inc., New Albany, Ohio, Jason M. Hurst, MD, Orthopaedic Surgeon, Joint Implant Surgeons, Inc., New Albany, Ohio, Attending Surgeon, Mount Carmel Health System, Columbus, Ohio, Michael J. Morris, MD, Orthopaedic Surgeon, Joint Implant Surgeons, Inc., New Albany, Ohio, Attending Surgeon, Mount Carmel Health System, Columbus, Ohio, Adolph V. Lombardi, Jr., MD, FACS, President, Joint Implant Surgeons, Inc., New Albany, Ohio, Clinical Assistant Professor, Department of Orthopaedics, The Ohio State University Wexner Medical Center, Columbus, Ohio, Attending Surgeon, Mount Carmel Health System, Columbus, Ohio, Keith R. Berend, MD , Vice President, Joint Implant Surgeons, Inc., New Albany, Ohio, President, White Fence Surgical Suites, LLC, New Albany, Ohio, Attending Surgeon, Mount Carmel Health System, Columbus, Ohio
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Background: Preoperative planning for implant sizes can help ensure proper implants are available as well as improve surgical efficiencies. The purpose of this study is to determine if patient gender and height can accurately predict the femoral size of the Oxford® knee.
Materials and Methods: 3986 knees (2085 female and 1901 males) that underwent a medial unicondylar knee arthroplasty (UKA) with the Oxford® mobile bearing knee (Zimmer Biomet, Warsaw, Indiana) were reviewed. Patient gender and height were compared to operative reports of the implanted femoral component. The relationship of height and femur size was then compared to create a prediction table for implant size.
Results: Females mean height was 64” (range, 48 to 78”) and males mean height was 70” (range, 58 to 79”). In male patients, large implants were used in the majority of cases (76.6%). In female patients, small implants were used in the majority of cases (64.3%). Based on the relationship of height and femur size, two groups were created for each gender. In males: ≤66” = medium and ≥67” = large. In females: ≤64” = small and ≥65” = medium. Using these cutoffs, the correct implant would be chosen in 78.7% of cases (82.1% in males and 75.6% in females). Extra-small and extra-large sizes were used at the extremes of height in each gender, but never more commonly than small, medium, or large at any height.
Conclusion: Patient gender and height can accurately predict femoral size of the Oxford® knee in the majority of cases. Our findings validate the original report of this method.
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The Evolution of Cement Fixation in Total Knee Arthroplasty
William Carpenter, MD, Dustin Hunter Hamilton, MD, Tyler Luthringer, MD , Daniel Buchalter, MD, Ran Schwarzkopf, MD, Associate Professor, NYU Langone Orthopaedic Hospital, New York, New York
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Aseptic loosening and infection are two of the leading causes of revision in total knee arthroplasty. While several patient-related factors can play a role in the development of these complications, there are certain modifiable surgeon factors that can help mitigate the risk. Intraoperatively, this can begin with the curing process of bone cement which is broken down into four different stages: mixing, waiting, working, and setting. Understanding each stage of the process is beneficial in obtaining successful long-term outcomes. Developing optimal bone-cement penetration is of utmost importance in establishing a strong interface. Proper penetration of cement is dependent on multiple factors including the cement’s properties along with its application to the prosthesis and bone surfaces. Combinations of different cement application techniques have yielded results with varying bone-cement interface strength. While a proper cementation technique is critical to the long-term success of a total knee replacement, other factors, such as antibiotic-loaded bone cement (ALBC), can help prevent and treat complications (such as infection). Although ALBC was not approved in North America by the Food and Drug Administration (FDA) until 2003, it was first described in 1970 and has been routinely used in revision total knee arthroplasty with reliable antibiotic elution properties and an acceptable safety profile.
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Comparison of a Posterior versus Anterior Approach for Lumbar Interbody Fusion Surgery Based on Relative Value Units
Nipun Sodhi, MD, Resident Physician, PGY-1, Long Island Jewish Medical Center, Northwell Health, New York, New York, Yatindra Patel, BS, Case Western Reserve University, School of Medicine, Cleveland, Ohio, Ryan J. Berger, MD, Resident Physician , Hiba K. Anis, MD, Research Fellow, Anton Khlopas, MD, Resident Physician – PGY-1, Cleveland Clinic, Cleveland, Ohio, Jared M. Newman, MD, Resident Physician – PGY-1, Rohan Desai, MD, Orthopaedic Resident , Douglas A. Hollern, MD, Orthopaedic Resident, SUNY Downstate Medical Center, Brooklyn, New York, Jeffrey M. Schwartz, MD, Chief of Orthopaedic Surgery, Kings County Hospital Center, Brooklyn, New York, Carl B. Paulino, MD, Program Director, Orthopaedic Surgeon, Joseph O. Ehiorobo, MD, Research Fellow, Michael A. Mont, MD, System Chief of Adult Reconstruction, Vice President, Strategic Initiatives, Lenox Hill Hospital, Northwell Health, New York, New York
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Introduction: The current value-driven healthcare system encourages physicians to continuously optimize the value of the services they provide. Relative value units (RVUs) serve as the basis of a reimbursement model linking the concept that as the effort and value of services provided to patient’s increases, physician reimbursement should increase proportionately. Spine surgery is particularly affected by these factors as there are multiple ways to achieve similar outcomes, some of which require more time, effort, and risk. Specifically, as the trend of spinal interbody fusion has increased over the past decade, the optimal approach to use—posterior versus anterior lumbar interbody fusion (PLIF vs. ALIF)—has been a source of controversy. Due to potential discrepancies in effort, one factor to consider is the correlation between RVUs and the time needed to perform a procedure. Therefore, the purpose of this study was to compare: 1) mean RVUs; 2) mean operative time; and 3) mean RVUs per unit of time between PLIF and ALIF with the utilization of a national surgical database. We also performed an individual surgeon cost benefit analysis for performing PLIF versus ALIF.
Materials and Methods: The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database was utilized to identify 6,834 patients who underwent PLIF (CPT code: 22630) and 6,985 patients who underwent ALIF (CPT code: 22558) between 2008 and 2015. The mean operative times (in minutes), mean RVUs, and RVUs per minute were calculated and compared using the Student’s t-tests. In addition, the reimbursement amount (in dollars) per minute, case, day, and year for an individual surgeon performing PLIF versus ALIF were also calculated and compared. A p-value of less than 0.05 was used as the threshold for statistical significance.
Results: Compared to ALIF cases, PLIF cases had longer mean operative times (203 vs. 212 minutes, p<0.001). However, PLIF cases were assigned lower mean RVUs than ALIF cases (22.08 vs. 23.52, p<0.001). Furthermore, PLIF had a lower mean RVU/minutes than ALIF cases (0.126 vs. 0.154, p<0.001). The reimbursement amounts calculated for PLIF versus ALIF were: $4.52 versus $5.53 per minute, $958.66 versus $1,121.95 per case, and $2,875.98 versus $3,365.86 per day. The annual cost difference was $78,380.92.
Conclusion: The data from this study indicates a potentially greater annual compensation of nearly $80,000 for performing ALIF as opposed to PLIF due to a higher “hourly rate” for ALIF as is noted by the significantly greater RVU per minute (0.154 vs. 0.126 RVU/minutes). These results can be used by spine surgeons to design more appropriate compensation effective practices while still providing quality care.
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The Safety and Efficacy of a Novel Cell-Based Gene Therapy for Knee Osteoarthritis
Hytham S. Salem, MD, Clinical Research Fellow, Joseph O. Ehiorobo, MD, Clinical Research Fellow, Michael A. Mont, MD, System Chief of Joint Reconstruction, Vice President, Strategic Initiatives, Lenox Hill Hospital, Northwell Health, New York, New York , Javad Parvizi, MD, Professor of Orthopaedic Surgery, Rothman Orthopaedic Institute, Philadelphia, Pennsylvania
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A promising new gene technology has been developed for the treatment of osteoarthritis, utilizing transduced human cells expressing transforming growth factor-β1. The safety and efficacy of this treatment modality has been demonstrated in laboratory studies, as well as Phase I, II, and current Phase III human clinical trials. Due to a misidentification error, there have been concerns that this cell-based gene therapy is based on a different cell than the one that was initially approved. However, its safety profile has been demonstrated by over 10 years of data revealing no evidence of tumorigenicity or other long-term safety concerns. In all studies to date, there have been no treatment-related serious adverse events. Although the nomenclature of one component of the drug product has changed, the product itself has not. In this review, we will present the technology, history of use (animal and clinical studies), development, efficacy, and, despite the recent misidentification error, the overall safety of this treatment modality.
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Surgical Approach and Hip Laterality Affect Accuracy of Acetabular Component Placement in Primary Total Hip Arthroplasty
David A. Crawford, MD, Joanne B. Adams, BFA, CMI, Adolph V. Lombardi, Jr., MD, FACS, President, Joint Implant Surgeons, Inc., The Ohio State University Wexner Medical Center, Columbus, Ohio, Keith R. Berend, MD, Vice President , Joint Implant Surgeons, Inc., New Albany, Ohio, Gerald R. Hobbs, PhD, Associate Professor of Statistics-Emeritus, West Virginia University, Morgantown, West Virginia
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Introduction: Controversy remains if the anterior approach improves acetabular component alignment, and many studies have compared approaches with different surgeons over different timeframes. The purpose of this study was to assess a single surgeon’s experience over a one-year timeframe and radiographically compare acetabular component positioning with the direct anterior versus direct lateral approach. Secondarily, this study compares acetabular component position differences between right and left hips for a right-hand dominant surgeon. Materials and Methods: Postoperative radiographs of 289 primary total hip arthroplasties (THAs) performed by a single right-hand dominant surgeon in 2014 were reviewed for abduction, anteversion, and medial cup seating. Component position was compared to surgical approach with 152 direct anterior (DA) THAs (53%) and 137 direct lateral (DL) THAs (47%). The operative side was also compared to surgeon hand dominance. Surgeons target was 40° abduction, 20° anteversion ±5°, and seating to the teardrop ±5mm. Lewinnek target was also assessed. Results: DA hips had a significantly lower abduction angle (p=0.04), less abduction target outliers (p<0.001), less abduction Lewinnek outliers (p<0.001), less target anteversion outliers (p<0.001), closer seating to teardrop (p<0.001), and less seating outliers (p<0.001). The combined target and Lewinnek safe zone were achieved more often in DA (p<0.001, p=0.042). Controlling for body mass index (BMI), the combined target achievement remained significantly better for DA (p=0.02), but combined Lewinnek was not significant (p=0.07). In the DA approach, right hips had a significantly lower abduction angle (p=0.03), less Lewinnek anteversion outliers (p=0.043), and less combined Lewinnek outliers (p=0.027). In the DL group, right hips had significantly higher anteversion angles (p=0.004) and Lewinnek anteversion outliers (p=0.033). Conclusion: The anterior approach improved target abduction, anteversion, and medialization compared to the direct lateral approach. Significant differences in component positioning were found in both approaches based on the surgeons dominant and non-dominant side.
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Does a Triple-Wedge, Broach-Only Stem Design Reduce Early Postoperative Fracture in Anterior Total Hip Arthroplasty?
David A. Crawford, MD, Heath Rutledge-Jukes, Keith R. Berend, MD, Michael J. Morris, MD, Joint Implant Surgeons, Inc., New Albany, Ohio
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Introduction: The direct anterior (DA) approach for total hip arthroplasty (THA) is gaining popularity; however, this approach still poses a higher risk for femoral complications, including fracture. The design of cementless stems can also impact the risk of fracture. The purpose of this study is to evaluate the early postoperative femoral complications with a short, triple-wedge broach-only tapered stem used in primary THA via a DA approach.
Materials and Methods: A retrospective review of our institution’s arthroplasty registry from 2015 through 2018 was performed to identify all patients who underwent a primary total hip arthroplasty via a direct anterior approach with the Klassic® Blade Stem (Total Joint Orthopedics, Inc., Salt Lake City, Utah). Patients were excluded if the stem was used for a revision surgery, within 90 days of surgery, or if research consent was refused. Two-hundred forty-five patients (289 hips) met inclusion criteria. Clinical and operative notes were reviewed, along with postoperative radiographs.
Results: Average follow up was 0.6 years (range, 0.25 to 3.6 years). Mean patient age was 62.9 years and mean body mass index (BMI) was 29.4 kg/m2. Gender was male in 130 patients (53%) and female in 115 patients (47%). No patients sustained an early postoperative periprosthetic femur fracture. No femoral revisions have been performed at most recent follow up. All 150 patients with >90-day postoperative radiographs demonstrated bony ingrowth of the stem. Early outcomes scores showed a mean postoperative Harris Hip Scores (HHS) of 80.1 (range, 10 to 100) and a pain score of 35.9 (range, 0 to 44).
Conclusion: This triple-wedge broach-only implant demonstrated low rates of early perioperative femoral complications in primary THA via a direct anterior approach. The authors will continue to monitor the longer-term survival and patient outcomes with this implant.
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An Update to a Novel Technique for Centering the Femoral Stem in Primary Total Hip Arthroplasty
Olivia J. Bono, BA, Dustin J. Schuett, DO, James V. Bono, MD, Vice Chair of Orthopaedics, John S. Shields, MD, Wake Forest Baptist Health, Bermuda Run, North Carolina, John Pinski, MD, Tufts University School of Medicine , Boston, Massachusetts
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Careful surgical technique is a critical component of total hip arthroplasty. Femoral preparation and component positioning are vital to improving outcomes and preventing complications. Femoral preparation begins with creating an entry hole in the proximal femur. Various tools have been used for this purpose which resemble a “cookie cutter.” An axial starter reamer, or awl, is then inserted through the entry hole in the proximal femur to aid in opening and centralizing the canal for sequential reaming or broaching. A novel technique was described previously which allows the awl to center itself in the canal with little risk of deviation from midline or cortical perforation. Since describing this technique in 2014, the senior surgeon has further modified the method of preparing the entry hole in the proximal femur. The surgeon now uses a 1/8” drill bit to penetrate the piriformis fossa, instead of a “cookie cutter” or osteotome. A 1/8” entry hole eliminates gaps between the bone and the implant, results in lateralization of the stem, and avoids varus malposition. We evaluated 300 primary hip arthroplasties by a single surgeon using one of the three techniques: traditional clockwise technique (Group 1), our previously published novel counterclockwise technique (Group 2), and our updated novel technique (Group 3). While the deviation from midline of Group 3 did not differ significantly from Group 2, it was significantly less than the deviation from midline of Group 1 (p=00006). This simple updated technique enables the surgeon to avoid potential malalignment during femoral preparation.
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Biomechanical Study Comparing Cut-out Resistance of the X-Bolt® and Dynamic Hip Screw at Various Tip-Apex Distances
Steven Kahane, MBBS, MSc, FRCS (Tr & Orth), Gold Coast University Hospital, Queensland, Australia, Kalpesh R. Vaghela, MBBS, BSc, MSc, MRCS, Royal London Hospital, , London, UK, John Stammers, MBBS, BSc, FRCS (Tr & Orth), Rothman Institute, Philadelphia, PA, USA, Andy Goldberg, MD, MBBS, FRCS (Tr & Orth), Royal National Orthopaedic Hospital, Middlesex, UK, Peter Smitham, PhD, FRCS (Tr & Orth), Royal Adelaide Hospital, University of Adelaide, South Australia, Australia
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Background: Bone quality in hip fractures is poor and there is a need to not only correctly position metalwork within the femoral head, but also for implants to resist cut-out. New implant designs may help to reduce metalwork cut-out, leading to fewer failures of fixation. This study compared the cut-out strength of a Dynamic Hip Screw (DHS) to that of an X-Bolt® (X-Bolt Orthopaedics, Dublin, Ireland) implant in an osteoporotic Sawbones® (Sawbones, Vashon Island, WA) model.
Methods: An unstable fracture model (AO 31-A2) was created using low-density 5 pound per cubic foot (pcf) Sawbones®. The DHS and X-Bolts® were inserted into the Sawbones® femoral head at Tip-Apex Distances (TAD) of 10mm, 15mm, 20mm, 25mm, 30mm and 40mm. A cyclic-loading Instron® machine (Instron Corp., Norwood, MA) pushed the bone at a compression rate of 5mm per minute at a 20-degree angle to the axis of the implant with an upper force limit of 4000N. Maximum force reached and load to failure, defined as movement of the implant by 5mm, were recorded. Four implants were used per group to give a total of 48 tests between the two groups.
Results: The X-Bolt® demonstrated a superior average maximum total load push-out force compared to the DHS group for all of the TAD configurations tested. The maximum force reached in the X-Bolt® group was significantly higher than that in the DHS group at a TAD of 10mm (X-Bolt® 3299.25N vs. DHS 2843.75N, P<0.029) and 30mm (X-Bolt® 2908.25N vs. DHS 2030N, P<0.029). The X-Bolt® also had a higher load to failure than the DHS group at all of the TAD values tested.
Conclusions: The X-Bolt® implant gave superior performance compared to the standard DHS, as reflected by a greater push-out force in an osteoporotic Sawbones® model.
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Concomitant Septic Arthritis of the Hip in Patients with Osteonecrosis of the Femoral Head
Young-Kyun Lee, MD, PhD, Associate Professor , Seokhyung Won, MD, Jiung Yeom, MD, Jung Wee Park, MD, Seok Min Lim, MD, Jin Woo Im, MD, Kyung-Hoi Koo, MD, PhD, Professor, Seoul National University Bundang Hospital, Seongnam, South Korea
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Introduction: Septic hip is a rare condition and is known to occur in immune-compromised patients. In general, surgeons are not concerned about the superimposed septic hip when they operate on patients with osteonecrosis of the femoral head (ONFH) if the patient is not immune compromised.
We evaluated 1) the proportion of septic arthritis among patients with ONFH, 2) the clinical and laboratory features, and 3) the outcomes of two-stage THA in those patients.
Materials and Methods: We identified patients who were diagnosed as having concomitant septic arthritis of the hip among 1,226 patients who underwent THA due to ONFH from 2011 to 2018 at our institution. A diagnosis of septic arthritis was made by aspirated joint fluid; white blood cell (WBC) count >15,000/ml and neutrophils >75%, microbiological culture, and/or the findings of septic arthritis on magnetic resonance imaging (MRI) scan. Osteonecrotic patients with infection were treated with two-stage THA.
Results: Among the 1,226 osteonecrotic patients, 14 (1.1%) had concomitant septic arthritis of the hip. There were nine men and five women. None of them were immune compromised or had a remote septic focus. In the preoperative evaluation, all 14 patients had elevated serum erythrocyte sedimentation rate (ESR) (>20mm/hr) and/or C-reactive protein (CRP) (>0.5mg/dL), and three patients had a fever (>37.5°C). Findings of septic hip were seen in all 12 patients who had preoperative MRI. The neutrophil count in the high-power field was >5 in all 12 patients who had intraoperative frozen section histology. The 14 patients were followed for one to seven years after the arthroplasty, and no patient had evidence of infection at the final follow up.
Conclusion: When a patient with ONFH has an unexplained elevation of ESR and/or CRP, concomitant septic arthritis of the hip should be suspected.
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The Combined Therapy of Tantalum Rod Implantation and Vascularized Bone Transplantation for Femoral Head Osteonecrosis: A Retrospective Long-Term Follow-Up Survival Analysis
Dewei Zhao, MD, Zhongshan District, Dalian, Liaoning Province, China, Liangliang Cheng, MD, Assistant Professor, Lei Yang, MD, Professor, Benjie Wang, MD, Professor, Baoyi Liu, MD, Assistant Professor of Orthopaedics, Affiliated Zhongshan Hospital of Dalian University, No.6 Jiefang Street, Zhongshan District, Dalian, Liaoning Province, China
1189
Tantalum rod implantation with vascularized bone transplantation has been reported to be an effective method for the treatment of osteonecrosis of the femoral head (ONFH). However, long-term follow-up results were unclear. Sixty-five patients (71 hips) with ONFH treated with this technique were retrospectively reviewed. According to the Association Research Circulation Osseous (ARCO) classification, 21 hips were stage II, 30 were stage III, and 15 were stage IV. Sixty-one patients (66 hips) were followed for more than 10 years. Fifteen hips had to be converted to total hip arthroplasty (THA), the proportion of THA conversion surgery over 10 years postoperative was 4.76% for stage II, 16.7% for stage III, and 60% for stage IV, respectively. The 10-year joint-preserving success rate of the entire group was 77.2%. The Harris Hip Score (HHS) in the patients not receiving THA therapy increased from a mean of 51.35 points (ranged from 32 to 62 points) to 90.12 points (ranged from 72 to 99 points). The technique of tantalum rod implantation with vascularized bone grafting was an effective joint-preserving method for the treatment of ARCO stage II-III ONFH.
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Targeting Core Decompression and Cell Therapy Injection of Hip Osteonecrosis with Computer-Assisted Navigation
Skender Ukaj, MD,Central Clinic University of Kosovo, Pristina, Kosovo, Philippe Hernigou, MD, Professor of Orthopedic Surgery, University of Paris Est, Paris, France, Jean Charles Auregan, MD, Assistant Professor, Hôpital Antoine-Béclère Université Paris-Sud, Clamart, France
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Purpose: Surgical treatment of hip osteonecrosis with stem cell therapy is a new procedure in which cells are injected with a trocar under fluoroscopic guidance. Proper surgical technique to obtain appropriate placement of the trocar in the center of the osteonecrosis is sometimes difficult and can require additional radiation exposure until the surgeon is satisfied with the trocar position. This study describes an improvement of this procedure using computer-assisted navigation.
Methods: A prospective, randomized study was conducted on cadavers using surgical trainees with no experience and one expert surgeon in surgical core decompression. During a training session, 3 novice surgeons underwent a test by performing the surgical task (core decompression) on a cadaver hip using fluoroscopic guidance. These trainee surgeons then placed the Kirschner wire under computer-assisted navigation. Osteonecrosis was defined as a target volume situated on the superior and anterior part of the femoral head. Performance during the tests was evaluated by radiographic analysis of trocar placement and by the measurement of radiation exposure.
Results: During the cadaver session, computer-assisted navigation achieved a better match to the ideal position of the trocar, with better trocar placement in terms of the tip-to-subchondral distance and the ideal center position. Computer-assisted navigation was associated with fewer attempts to position the trocar, a shorter duration of fluoroscopy, and decreased radiation exposure compared to surgery performed under conventional fluoroscopy.
Conclusions: The findings suggest that computer-assisted navigation may be safely used to train surgical novices in core decompression. This technique avoids the use of both live patients and harmful radiation. For expert surgeons, computer-assisted navigation might improve precision with less radiation, which might be desirable in cell therapy.
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Computed Tomography Staging of Osteonecrosis of the Femoral Head
Beomseok Lee, MD, Dong Min Lee, MD, Gwangmyeong Sungae Hospital, Gwangmyeong, South Korea, Yong-Chan Ha, MD, Professor, Jae-Young Lim, MD, Chung-Ang University College of Medicine, Seoul, South Korea, Jung Wee Park, MD, Young-Kyun Lee, MD, Associate Professor, Kyung-Hoi Koo, MD, Professor, Seoul National University College of Medicine, Seongnam, South Korea
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Introduction: Osteonecrosis of the femoral head (ONFH) usually affects patients younger than 50 years and frequently leads to collapse of the femoral head and subsequent osteoarthritis of the hip. Joint-preserving procedures are attempted in the early stages without collapse, while total hip arthroplasty (THA) is done during more advanced stages with femoral head collapse or a fracture in the necrotic portion. Thus, accurate staging of the disease is mandatory to decide therapeutic strategy. The purpose of this study is to determine the prevalence of occult fracture in the necrotic portion among osteonecrotic femoral heads, which were classified as Association Research Circulation Osseous (ARCO) stage 1 or 2 on radiographs.
Materials and Methods: A preoperative computer tomography (CT) scan was routinely performed to obtain an adequate cup position in patients undergoing THA at our institution. Radiographs and CT scans of 308 patients, who underwent unilateral THA due to ONFH from January 2011 to December 2014, were assessed by two orthopedic surgeons to compare the stage based on simple radiography and that based on CT scans.
Results: Among the 308 hips, which were classified as stage I or II lesions on simple radiography, fracture inside the necrotic portion was seen in 63 hips (20.5%) on CT scans. Fifty-nine of the 63 patients were followed for two to five years. Further collapse of the femoral head occurred in 41 patients, and 36 of them underwent THA during the follow up.
Conclusion: In this study, 20.5% of hips classified as ARCO stage I or II on simple radiography were found to be ARCO stage III on CT imaging. When a joint-preserving treatment is considered for early stage ONFH, CT examination is necessary for more precise staging of the disease.
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The Effects of Space Microgravity on Hip and Knee Cartilage: A New Frontier in Orthopaedics
Prem N. Ramkumar, MD, MBA, Anas A. Minkara, MD, Cleveland Clinic, Cleveland, Ohio, Heather S. Haeberle, BS, Sergio M. Navarro, MBA, Baylor College of Medicine, Houston, Texas, Jacob Becker, MD, University of Texas Health, San Antonio, Texas, Farhan Ahmad, BS, Oxford University, Oxford, United Kingdom, Michael A. Mont, MD, System Chief of Joint Reconstruction, Lenox Hill Hospital, New York, New York, Riley J. Williams, MD, Professor, Hospital for Special Surgery, New York, New York
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Introduction: Given the expansion of commercial and recreational space exploration, orthopaedic surgeons will need to understand the implications of microgravity on cartilaginous damage and to anticipate the resulting pathology from accelerated chondrolysis. The purpose of this systematic review is to evaluate the effects of space and microgravity on hip and knee articular cartilage, including its impact on joint mobility and functional status.
Materials and Methods: A review of the current literature was performed utilizing the terms “joints,” “joint mobility,” “articular cartilage,” “knee,” “hip,” “space,” “microgravity,” and “osteoarthritis” in PubMed and Google Scholar from 1990 to 2018, yielding a total of 1,400 citations following the removal of 500 duplicates. Following screening by eligibility criteria, five reports were included.
Results: Dysregulation of osteogenesis and weakened structural integrity of hip and knee cartilage were demonstrated secondary to microgravity. Adequate cartilage repair requires Earth-like conditions as signified by a statistically significant increase in serum cartilage oligomeric matrix protein concentrations in astronauts. Reduced loading led to the degradation of knee ligaments and menisci which may pose a risk for subluxation or dislocation. Murine studies demonstrated decreased articular cartilage thickness in the medial femoral condyle and patella as assessed by ultrasound. Additionally, glycosaminoglycan levels in unloaded rats were lower than weight-bearing rats, with a concomitant increase in matrix metalloproteinase-13 protein, degrading collagen. Return to weight-bearing demonstrated partial recovery of cartilaginous degeneration.
Conclusions: Space and associated microgravity conditions adversely impact articular cartilage as demonstrated in murine and human studies. The pathogenetic process occurs due to the mechanically responsive nature of cartilage, with an increase in cartilage metabolism in microgravity. There remains a marked paucity of literature regarding the gravitational force necessary for adequate cartilage survival and the impact of space-related radiation on cartilage repair. Additionally, further studies should assess pharmacologic interventions, such as recombinant human fibroblast growth factor to stimulate cartilaginous growth.
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The Effect Of Increasing Femoral Head Size On The Force Required For Dislocation
Matthew J. Dietz, MD, Assistant Professor, Vincent L. Kish, ASEE, Senior Instrumentation Technician, Obadah Moushmoush, BA, West Virginia University, School of Medicine, Morgantown, West Virginia, Walter P. Samora, MD, Clinical Assistant Professor, Nationwide Children’s Hospital, Columbus, Ohio, Brian R. Hamlin, MD, Assistant Director, Bone and Joint Center, Magee Women’s Hospital UPMC, Pittsburgh, Pennsylvania
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Alternative bearings allow for the increased utilization of large femoral heads in total hip arthroplasty. This study demonstrated the effect of increasing femoral head size on the force required for dislocation during intraoperative assessment. Using a standard posterior approach, 10 cadaver hips underwent total hip arthroplasty; components were implanted in a standard fashion. The extremity was attached to a custom jig to replicate intraoperative assessment (internal rotation with 90° of hip flexion/neutral adduction). This range of motion (ROM) was repeated in triplicate using femoral head sizes of 28mm, 32mm, 36mm, 40mm, and 44mm. The ROM to dislocation (degrees) and torque (N*m) required were recorded. With increasing head sizes, there was a significant increase in torque required for dislocation (p<0.0001). The least square means torques (N*m) for each femoral head size (28–44mm) were 2.07, 2.15, 2.42, 2.74, and 3.65N*m. The corresponding least square means ROMs prior to dislocation were 43.5°, 46.2°, 50.8°, 54.3°, and 59.5°. There was a significant difference in ROM between nonadjacent head sizes (i.e., 28mm and 44mm) (p<0.0001). Total hip implant stability is multifactorial. Increasing femoral head size may confer stability during intraoperative assessment by increasing both the ROM prior to dislocation and the force required for dislocation.
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