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Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_16 | Pages 38 - 38
17 Nov 2023
Al-Namnam NM Luczak AT Collishaw S Li X Lucas M Simpson AHRW
Full Access

Abstract

Introduction

Ultrasonic cutting in surgery has great potential. However, a key limitation is heat created by friction between the bone and the blade. Bone has poor thermal conductivity which hinders the dissipation of heat, causing cell death near the cut site In addition, ultrasonic vibration may create microcracks. It was hypothesised that these effects on bone would vary with the frequency and displacement of the ultrasonically powered blade. Therefore varying frequencies and displacements of the tip of the blade were studied to find the combination with fewest microcracks and lowest temperature rise at the bone-tool interface.

Aim

To explore the effect of different frequencies and tip displacements of ultrasonic cutting devices on the amount of thermal and mechanical damage.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_16 | Pages 59 - 59
17 Nov 2023
Yang I Buchanan R Al-Namnam N Li X Lucas M Simpson AH
Full Access

Abstract

Background

Ultrasonic cutting of bone boasts many advantages over alternatively powered surgical instruments, including but not limited to: elimination of swarf, reduced reaction forces, increased precision in cutting and reduced adjacent soft tissue damage, reduced post-operative complications such as bleeding and bone fracture, reduced healing time, reduced intra-operative noise and ease of handling. Despite ultrasonic cutting devices being well established in oral and maxillofacial surgery, applications in orthopaedic surgery are more niche and are not as well understood. The aim of this study was to investigate the cutting speed (mm/s) and cutting forces (N) of orthopaedic surgeons using a custom-designed state of the art ultrasonic cutting tool to cut fresh human bone samples.

Methods

A setup based on the Robot Operating System (ROS) and AprilTag was designed to track and to record the real time position of the ultrasonic cutting tool in space. Synchronised load cell axial force readings of three separate orthopaedic surgeons during ultrasonic cutting were recorded. Each surgeon was asked to find a comfortable position that reflects as close as possible their clinical handling of a cutting instrument used in surgery, and to perform two cuts in each of three samples of human cortical bone. Bone samples were obtained following ethical approval from an institutional review board (ethics approval number: SR1342) and prior informed consent was obtained from all patients. Bone samples were extracted from the femoral neck region of three hip osteoarthritis patients. During cutting, surgeons were allowed a total cutting time of one minute and cutting was conducted using an ultrasonic tool with frequency of a 35kHz (35.7 µm peak to peak displacement amplitude) under constant irrigation using a MINIPULS® 3 Peristaltic pump (38 revolutions per minute) using Phosphate-Buffered Saline (PBS) at 25°C. From the recorded data, the average instantaneous cutting velocity was calculated and the maximum cutting force was identified.


Bone & Joint Research
Vol. 11, Issue 9 | Pages 652 - 668
7 Sep 2022
Lv G Wang B Li L Li Y Li X He H Kuang L

Aims

Exosomes (exo) are involved in the progression of osteoarthritis (OA). This study aimed to investigate the function of dysfunctional chondrocyte-derived exo (DC-exo) on OA in rats and rat macrophages.

Methods

Rat-derived chondrocytes were isolated, and DCs induced with interleukin (IL)-1β were used for exo isolation. Rats with OA (n = 36) or macrophages were treated with DC-exo or phosphate-buffered saline (PBS). Macrophage polarization and autophagy, and degradation and chondrocyte activity of cartilage tissues, were examined. RNA sequencing was used to detect genes differentially expressed in DC-exo, followed by RNA pull-down and ribonucleoprotein immunoprecipitation (RIP). Long non-coding RNA osteoarthritis non-coding transcript (OANCT) and phosphoinositide-3-kinase regulatory subunit 5 (PIK3R5) were depleted in DC-exo-treated macrophages and OA rats, in order to observe macrophage polarization and cartilage degradation. The PI3K/AKT/mammalian target of rapamycin (mTOR) pathway activity in cells and tissues was measured using western blot.


Bone & Joint Research
Vol. 11, Issue 4 | Pages 251 - 251
30 Apr 2022
Wang X Wang D Xia P Cheng K Wang Q Wang X Lin Q Song J Chen A Li X


Bone & Joint Research
Vol. 10, Issue 10 | Pages 693 - 703
1 Oct 2021
Wang X Wang D Xia P Cheng K Wang Q Wang X Lin Q Song J Chen A Li X

Aims

To evaluate the effect of ultrasound-targeted simvastatin-loaded microbubble destruction (UTMDSV) for alleviation of the progression of osteoarthritis (OA) in rabbits through modulation of the peroxisome proliferator-activated receptor (PPARγ).

Methods

In vitro, OA chondrocytes were treated with ultrasound (US), US-targeted microbubble destruction (UTMD), simvastatin (SV), and UTMDSV on alternate days for four weeks. Chondrocytes were also treated with PPARγ inhibitor, PPARγ inhibitor+ UTMDSV, and UTMDSV. The cholesterol efflux rate and triglyceride levels were measured using an assay kit and oil red O staining, respectively. In vivo, the OA rabbits were treated with a single intra-articular injection of UTMD, SV, and UTMDSV every seven days for four weeks. Cartilage histopathology was assessed by safranin-O staining and the Mankin score. Total cholesterol (TC) and high-density lipoprotein-cholesterol (HDL-C) in rabbit knee synovial fluid were detected by enzyme-marker assay. Aggrecan, collagen II, and PPARγ expression levels were analyzed by Western blotting (WB).


Bone & Joint Research
Vol. 10, Issue 10 | Pages 668 - 676
1 Oct 2021
Liu L Li Z Chen S Cui H Li X Dai G Zhong F Hao W Zhang K Liu H

Aims

Acquired heterotopic ossification (HO) is a debilitating disease characterized by abnormal extraskeletal bone formation within soft-tissues after injury. The exact pathogenesis of HO remains unknown. It was reported that BRD4 may contribute to osteoblastic differentiation. The current study aims to determine the role of BRD4 in the pathogenesis of HO and whether it could be a potential target for HO therapy.

Methods

Achilles tendon puncture (ATP) mouse model was performed on ten-week-old male C57BL/6J mice. One week after ATP procedure, the mice were given different treatments (e.g. JQ1, shMancr). Achilles tendon samples were collected five weeks after treatment for RNA-seq and real-time quantitative polymerase chain reaction (RT-qPCR) analysis; the legs were removed for micro-CT imaging and subsequent histology. Human bone marrow mesenchymal stem cells (hBMSCs) were isolated and purified bone marrow collected during surgeries by using density gradient centrifugation. After a series of interventions such as knockdown or overexpressing BRD4, Alizarin red staining, RT-qPCR, and Western Blot (Runx2, alkaline phosphatase (ALP), Osx) were performed on hBMSCs.


Bone & Joint Research
Vol. 9, Issue 9 | Pages 587 - 592
5 Sep 2020
Qin L Li X Wang J Gong X Hu N Huang W

Aims

This study aimed to explore whether serum combined with synovial interleukin-6 (IL-6) measurement can improve the accuracy of prosthetic joint infection (PJI) diagnosis, and to establish the cut-off values of IL-6 in serum and synovial fluid in detecting chronic PJI.

Methods

Patients scheduled to have a revision surgery for indications of chronic infection of knee and hip arthroplasties or aseptic loosening of an implant were prospectively screened before being enrolled into this study. The Musculoskeletal Infection Society (MSIS) definition of PJI was used for the classification of cases as aseptic or infected. Serum CRP, ESR, IL-6, and percentage of polymorphonuclear neutrophils (PMN%) and IL-6 in synovial fluid were analyzed. Statistical tests were performed to compare these biomarkers in the two groups, and receiver operating characteristic (ROC) curves and area under the curve (AUC) were analyzed for each biomarker.


Bone & Joint Research
Vol. 9, Issue 8 | Pages 501 - 514
1 Aug 2020
Li X Yang Y Sun G Dai W Jie X Du Y Huang R Zhang J

Aims

Rheumatoid arthritis (RA) is a systematic autoimmune disorder, characterized by synovial inflammation, bone and cartilage destruction, and disease involvement in multiple organs. Although numerous drugs are employed in RA treatment, some respond little and suffer from severe side effects. This study aimed to screen the candidate therapeutic targets and promising drugs in a novel method.

Methods

We developed a module-based and cumulatively scoring approach that is a deeper-layer application of weighted gene co-expression network (WGCNA) and connectivity map (CMap) based on the high-throughput datasets.


Bone & Joint Research
Vol. 9, Issue 5 | Pages 236 - 241
1 May 2020
Li R Wang C Ji X Zheng Q Li X Ni M Zhang G Chen J

Aims

The purpose of this study was to validate our hypothesis that centrifugation may eliminate false-positive leucocyte esterase (LE) strip test results caused by autoimmune diseases in the diagnosis of knee infection.

Methods

Between January 2016 and May 2019, 83 cases, including 33 cases of septic arthritis and 50 cases of aseptic arthritis, were enrolled in this study. To further validate our hypothesis, another 34 cases of inflammatory arthritis from the Department of Rheumatology of our institution were also included. After aspiration, one drop of synovial fluid was applied to LE strips before and after centrifugation. The results were recorded after approximately three minutes according to the different colour grades on the colour chart. The differences of LE results between each cohort were analyzed.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_6 | Pages 69 - 69
1 Mar 2017
Veltre D Yi P Sing D Smith E Li X
Full Access

Introduction

Hip arthroplasty is one of the most common procedures performed every year however complications do occur. Prior studies have examined the impact of insurance status on complications after TJA in small or focused cohorts. The purpose of our study was to utilize a large all-payer inpatient healthcare database to evaluate the effect of patient insurance status on complications following hip arthroplasty.

Methods

Data was obtained from the Nationwide Inpatient Sample between 2004 and 2011. Analysis included patients undergoing hip arthroplasty procedures determined by ICD-9 procedure codes. Patient demographics and comorbidities were analyzed and stratified by insurance type. The primary outcome was medical complications, surgical complications and mortality during the same hospitalization. A secondary analysis was performed using a matched cohort comparing patients with Medicare vs private insurance using the coarsened exact matching algorithm. Pearson's chi-squared test and multivariate regression were performed.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_6 | Pages 68 - 68
1 Mar 2017
Veltre D Cusano A Yi P Sing D Eichinger J Jawa A Bedi A Li X
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INTRODUCTION

Shoulder arthroplasty (SA) is an effective procedure for managing patients with shoulder pain secondary to degenerative joint disease or end stage arthritis that has failed conservative treatment. Insurance status has been shown to be an indicator of patient morbidity and mortality. The objective of the current study is to evaluate the effect of patient insurance status on outcomes following shoulder replacement surgery.

METHODS

Data was obtained from the Nationwide Inpatient Sample between 2004 and 2011. Analysis included patients undergoing shoulder arthroplasty procedures determined by ICD-9 procedure codes. Patient demographics and comorbidities were analyzed and stratified by insurance type. The primary outcome was medical and surgical complications occurring during the same hospitalization with secondary analysis of mortality. Pearson's chi¬squared test and multivariate regression were performed.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_6 | Pages 70 - 70
1 Mar 2017
Veltre D Yi P Sing D Smith E Li X
Full Access

Introduction

Knee arthroplasty is one of the most common inpatient surgeries procedures performed every year however complications do occur. Prior studies have examined the impact of insurance status on complications after TJA in small or focused cohorts. The purpose of our study was to utilize a large all-payer inpatient healthcare database to evaluate the effect of patient insurance status on complications following knee arthroplasty.

Methods

Data was obtained from the Nationwide Inpatient Sample between 2004 and 2011. Analysis included patients undergoing knee arthroplasty procedures determined by ICD-9 procedure codes. Patient demographics and comorbidities were analyzed and stratified by insurance type. The primary outcome was medical complications, surgical complications and mortality during the same hospitalization. A secondary analysis was performed using a matched cohort comparing patients with Medicare vs private insurance using the coarsened exact matching algorithm. Pearson's chi-squared test and multivariate regression were performed.


Bone & Joint Research
Vol. 6, Issue 3 | Pages 154 - 161
1 Mar 2017
Liu J Li X Zhang H Gu R Wang Z Gao Z Xing L

Objectives

Ubiquitin E3 ligase-mediated protein degradation regulates osteoblast function. Itch, an E3 ligase, affects numerous cell functions by regulating ubiquitination and proteasomal degradation of related proteins. However, the Itch-related cellular and molecular mechanisms by which osteoblast differentiation and function are elevated during bone fracture repair are as yet unknown.

Methods

We examined the expression levels of E3 ligases and NF-κB members in callus samples during bone fracture repair by quantitative polymerase chain reaction (qPCR) and the total amount of ubiquitinated proteins by Western blot analysis in wild-type (WT) mice. The expression levels of osteoblast-associated genes in fracture callus from Itch knockout (KO) mice and their WT littermates were examined by qPCR. The effect of NF-κB on Itch expression in C2C12 osteoblast cells was determined by a chromatin immunoprecipitation (ChIP) assay.


Bone & Joint Research
Vol. 5, Issue 10 | Pages 492 - 499
1 Oct 2016
Li X Li M Lu J Hu Y Cui L Zhang D Yang Y

Objectives

To elucidate the effects of age on the expression levels of the receptor activator of the nuclear factor-κB ligand (RANKL) and osteoclasts in the periodontal ligament during orthodontic mechanical loading and post-orthodontic retention.

Materials and Methods

The study included 20 male Sprague-Dawley rats, ten in the young group (aged four to five weeks) and ten in the adult group (aged 18 to 20 weeks). In each rat, the upper-left first molar was subjected to a seven-day orthodontic force loading followed by a seven-day retention period. The upper-right first molar served as a control. The amount of orthodontic tooth movement was measured after seven-day force application and seven-day post-orthodontic retention. The expression levels of RANKL and the tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts were evaluated on day 7 (end of mechanical force loading) and day 14 (after seven days of post-orthodontic retention). Statistical analysis was performed using the t-test, and significance was set at p < 0.05.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_11 | Pages 32 - 32
1 Jul 2014
Curry E Li X Buesser K Nguyen J Matzkin E
Full Access

Summary Statement

The purpose is to evaluate the effects of internet usage on new patient referral patterns to identify optimal patient recruitment and communication. Overall, social networking and internet may be an effective way for surgeons to recruit a wider patient population.

Introduction

Prior studies in other medical specialties have shown that social networking and internet usage has become an increasingly important means of patient communication and referral. However, this information is lacking in the orthopaedics literature. In this study, we evaluate the means by which new patients arrive at orthopaedic clinics in a major academic center. The purpose is to evaluate the effects of internet or social media usage on new patient referral patterns to identify avenues to optimise patient recruitment and communication.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 602 - 602
1 Dec 2013
Zhou H Shaw J Li X
Full Access

Introduction:

Due to improvement in overall prosthesis designs and surgical methods, there have been increasing numbers of total ankle arthroplasty performed with encouraging intermediate results. While European registries have been able to perform long term follow-ups and analysis on total ankle arthroplasty patients, majority of the US studies have been based on experiences at a single institution. There is currently limited data on the recent trends of total ankle arthroplasty. The purpose of our study is to evaluate the in-patient demographics, complications and readmission rate in patients after total ankle arthroplasty at academic medical centers in United States.

Patients & Methods:

We queried the University Healthsystems Consortium (UHC) administrative database from 2007 to 2011 for patients who underwent total ankle arthrolasty by ICD-9 procedure code 81.56. A descriptive analysis of demographics was performed, followed by a similar analysis of patient clinical benchmarks, including hospital length of stay, hospital direct cost, in-hospital mortality, and 30-day readmission rates.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 240 - 240
1 Mar 2013
Li X Williams P Trivellas A Nguyen J Craig EV Warren R Gulotta L
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Introduction

There is a high prevalence of obesity in the United States and the numbers are increasing. These patients comprise a significant portion of the shoulder arthroplasty patient population. There are several reports of outcomes in the literature on obese patients after total knee or hip replacement, however, this data is lacking in the shoulder arthroplasty patient population. The purpose of this study is to compare the functional outcomes and complications of obese patients undergoing shoulder arthroplasty with the non-obese population.

Methods

Between 2009 to 2010, 76 patients that had a primary total shoulder replacement were grouped according to their Body Mass Index (BMI) and followed prospectively for 2 years. The groups were divided as normal (BMI <25, N=26), overweight (25 to 30 BMI, N=25), and obese (>30 BMI, N=25) according to the World Health Organization classifications. Preoperative demographics, age, comorbidities and postoperative complications were recorded. Perioperative operating room and hospital data were analyzed. Functional outcome measurements including ASES, SF-36 physical component (PC) scores, mental component (MC) scores and visual analog scale along with general health and fatigue were evaluated at the 0 and 2 year time period. Statistical analyses were performed.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 114 - 114
1 Mar 2013
Li X Knutson Z Choi D Lipman J Craig EV Warren R Gulotta L
Full Access

Introduction

While shoulder elevation can be reliably restored following reverse total shoulder arthroplasty (RTSA), patients may experience a loss of internal and external rotation. Several recent studies have investigated scapular notching and have made suggestions regarding glenosphere placement in order to minimize its occurrence. However, very few studies have looked at how changes in glenosphere placement in RTSA affect internal and external rotation. The purpose of this study was to determine the effect of glenosphere position on internal and external rotation range of motion at various degrees of scaption following RTSA. We hypothesized that alteration in glenosphere position will affect the amount of impingement-free internal and external rotation.

Methods

CT scans of the scapula and humerus were obtained from seven cadaver specimens and 3-Dimensional (3D) reconstructions were created. A corresponding 3D RTSA model was created by laser scanning the baseplate, glenosphere, humeral stem and bearing. The RTSA models were then virtually implanted into each specimen. The glenosphere position was determined in relation to the neutral position in 6 different settings: Medialization (5 mm), lateralization (10 mm), superior translation (6mm), inferior translation (6 mm), superior tilt (20°), and inferior tilt (15° and 30°). The humerus in each virtual model was allowed to freely rotate at a fixed scaption angle until encountering bone-bone or bone-implant impingement (180 degrees of limitation). Each model was tested at 0, 20, 40, and 60 degrees of scaption and the impingement-free internal and external rotation range of motion for each scaption angle was recorded.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXX | Pages 31 - 31
1 Jul 2012
Watanuki M Gaston C Li X Grimer R
Full Access

Introduction

It is generally held that blood tests are not particularly helpful in establishing the diagnosis of bone tumours but may be useful in prognosis. We reviewed the results of blood tests taken at the time of diagnosis to establish the frequency of abnormalities in common blood tests and whether this was significant in staging or prognosis.

Method

Blood test results on all newly diagnosed patients with bone tumours from 2005 – 2010 were exported and abnormalities identified. This was matched to diagnosis, clinical features and prognosis.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_III | Pages 405 - 405
1 Oct 2006
He Q Wan C Li X Lee G Gardiner T Li G
Full Access

Introduction: The existence of peripheral blood (PB) derived mesenchynal stem cells (PBMSCs) have been documented in several species including human. The circulating skeletal stem cells may provide a new source of stem cells that may be used for skeletal and other tissue engineering applications. The objective of this study is to further investigate and compare the biological characteristics of the PBMSCs with bone marrow derived MSCs in the GFP rats.

Methods: The peripheral blood (PB) from the GFP rats was harvested by cardiac puncture using syringes containing sodium heparin. Mononuclear cells were isolated by density gradient centrifugation method and plated at a density of 1–3~105/cm2 in flasks with D-MEM medium containing 15% FCS. The bone marrow (BM) was also collected for obtaining BMMSCs, the bone chips for osteoblastic cells, and the skin for skin fibroblasts. The phenotypes of the cells were characterized by immunocytochemistry (ICC), and flow cytometry methods. Gene expression profiles of 3-paired PBMSCs and BMMSCs cDNA samples were examined by Affymetrix gene chips microarray analysis. The multipotent differentiation potentials of PBMSCs into osteoblasts, chondrocytes, and adipocytes were examined under specific inductive conditions and checked with lineage specific markers. Finally, the osteogenic potential of the PBMSCs was examined by an in vivo implantation model in which the PBMSCs were seeded with HA-TCP powder complexes, and implanted subcutaneously in the severe compromised immunodeficiency (SCID) mice for 12 weeks, whereas the bone-derived osteoblasts and skin fibroblasts were used as controls.

Results: Compared with the BMMSCs, the PBMSCs shared some but not all common surface markers as demonstrated by (ICC) and flow cytometry examinations. The osteogenic differentiation of PBMSCs was defined with positive staining of type I collagen and osteocalcin; positive staining for alkaline phosphatase and Von Kossa staining for mineralized bone nodules. Adipogenic differentiation was evidenced by positive Oil red-O staining for accumulated lipids, and chondrogenic differentiation by positive type II collagen and Saferinin O positive staining. For gene expression profiles, in the Affymetrix chip general analysis, 83 genes were up regulated and 84 genes down regulated in the PBMSCs (vs BMMSCs, > 2 fold, E-B/B-E> 100, p< 0.05). Most of which genes are related to cell proliferation, differentiation, cytoskeleton, and calcium/iron homeostasis. After 12 weeks implantation in SCID mice, newly formed lamellar bone was clearly evident in the groups with PBMSCs implants, so as in the groups with osteoblasts implants, but only fibrous tissue was found in the group implanted with skin fibroblasts.

Discussion: This study demonstrated that the multi-potent PBMSCs in the GFP rats resemble BMMSCs in many aspects, but they are distinguishable from the BMMSCs in some biological characteristics and gene profiles. Our study has confirmed that these PBMSCs possess osteogenic potential in vitro and in vivo, suggesting that these circulating stem cells could serve as an alternative source as bone marrow derived MSCs for tissue engineering purposes.