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Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_4 | Pages 63 - 63
1 Mar 2021
Mobasheri A
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Calcium is an important element for a wide range of physiological functions including muscle contraction, neuronal activity, exocytosis, blood coagulation and cell communication. In the musculoskeletal system calcium is crucial for the structural integrity of bones, teeth, intervertebral disc and articular cartilage. At the cellular level calcium acts as a second messenger. Calcium signalling uses intracellular calcium ions to drive intracellular communication and signal transduction processes. When calcium enters the cell it exerts allosteric regulatory effects on many enzymes and proteins. Examining the role of calcium in chondrocyte biology is important for understanding the role for this divalent ion in the metabolic modulation of chondrocyte function in health and disease. This includes the study of calcium transport systems such as channels, transporters and pumps involved in calcium homeostasis in chondrocytes and how existing pharmacological drugs act on these transport systems. L-type calcium channel blockers are drugs used as cardiac antiarrhythmics or antihypertensives, depending on whether the drugs have higher affinity for the heart (the phenylalkylamines, like verapamil), or for the blood vessels (the dihydropyridines, like nifedipine). L-type calcium channels are present in many musculoskeletal tissues including skeletal muscle, smooth muscle, bone and cartilage. L-type calcium channel inhibitors like nifedipine used for the treatment of some forms of hypertension modulate calcium-mediated events in chondrocytes under dynamic loading, thus affecting metabolism, osmotic responses and extracellular matrix turnover in cartilage. The aim of our work is to understand the impact of L-type calcium channel inhibitors used for the treatment of hypertension on chondrocytes and on the chondrogenic differentiation of bone marrow derived mesenchymal stem cells (MSCs). This knowledge will enhance our understanding of the development of osteoarthritis (OA) and may lead to new opportunities for chondroprotection and regenerative medicine for OA. We have used electrophysiology to demonstrate L-type calcium currents in chondrocytes immediately after pharmacological activation with the calcium channel opener Bay-K8644. We have also used immunohistochemistry to demonstrate expression of the a1C subunit Ca. v. 1.2 (CACNA1C) in human chondrocytes and MSCs. Inhibitors of L-type calcium channels such as nifedipine downregulate mitochondrial respiration and ATP production in MSCs but not in chondrocytes. Nifedipine inhibits proliferation of chondrocytes and enhances glycolytic capacity in chondrocytes, promoting glycolytic reserve in both MSCs and chondrocytes. Nifedipine can also stimulate chondrogenic differentiation in MSCs (with or without growth factors). Metabolic responses to nifedipine differs in mesenchymal stem cells and chondrocytes highlighting important metabolic differences between these cells. In summary, antihypertensive drugs such as nifedipine can affect the biological function of chondrocytes and MSCs and may modulate the course of OA progression and impact on cartilage repair


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_9 | Pages 89 - 89
17 Apr 2023
Alzahrani S Aljuaid M Bazaid Z Shurbaji S
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A Morel-Lavallee lesion (MLL) is a benign cystic lesion that occurs due to injury to the soft-tissue envelope's perforating vascular and lymphatic systems, resulting in a distinctive hemolymphatic fluid accumulation between the tissue layers. The MLL has the potential to make a significant impact on the treatment of orthopaedic injuries. A 79-year-old male patient community ambulatory with assisting aid (cane) known case of Diabetes mellitus, hypertension, bronchial asthma and ischemic heart disease. He was brought to the Emergency, complaining of right hip discomfort and burning sensation for the last 5 days with no history of recent trauma at all. Patient had history of right trochanteric femur fracture 3 years ago, treated with DHS in a privet service. Clinical and Radiological assessment showed that the patient mostly has acute MLL due to lag screw cut out. We offered the patient the surgical intervention, but he refused despite explaining the risks of complications if not treated and preferred to receive the conservative treatment. Compression therapy management explained to him including biker's shorts (instructed to be worn full-time a day) and regular follow up in clinic. Symptom's improvement was reported by the patient in the subsequent visits. In the polytrauma patient, a delayed diagnosis of these lesions is conceivable due to the presence of more visible injuries. It's located over the greater trochanter more commonly, but sometimes in other areas such as the lower lumbar region, the thigh, or the calf. Incorrect or delayed diagnosis and care can have unfavorable outcomes such as infection, pseudocyst development, and cosmetologically deformity. Magnetic resonance imaging (MRI) and ultrasound will aid in MLL diagnosis. However, the effectiveness of MLL therapy remains debatable. We strongly believe that the MLL caused due to tangential shear forces applied to the soft tissue leads to accumulation of the blood and/or lymph between the subcutaneous and overlying fascia and it often misdiagnosed due to other distracting injuries. Nontheless, in our case we reported MLL occur due to internal pressure on the fascia caused by cut out of DHS lag screw


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_13 | Pages 145 - 145
1 Nov 2021
Papalia R Torre G Zampogna B Vorini F De Vincentis A Denaro V
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Introduction and Objective. Several factors contribute to the duration of the hospital stay in patients that undergo to total hip arthroplasty (THA), either subjective or perioperative. However, no definite evidence has been provided on the role of any of these factors on the hospitalization length. The aim of this retrospective investigation is to evaluate the correlation between several preoperative and perioperative factors and the length of hospital stay (LOS) in patients that underwent elective total hip arthroplasty. Materials and Methods. Medical records of patients that underwent THA since the beginning of 2016 to the end of 2018 were retrospectively screened. Demographics, comorbidities, renal function, whole blood count. and length of post-operative ward stay were retrieved. The association between clinical, biochemical and surgical factors and the length of hospital stay was explored by means of linear regression models. Results. A total of 743 subjects were included. Retrieved comorbidity included arterial hypertension (47%), dyslipidaemia (20%), chronic kidney disease (CKD) (12%) and diabetes mellitus (9%). The median length of post-operative hospital stay was 4 days (IQR: 2). Variables associated with linear increase of hospitalization length were the estimated Glomerular Filtration Rate (eGFR) (Beta −0.01, 95% CI −0.02, 0), CKD (Beta 0.82, 95% CI 0.29, 1.34), duration of surgery (Beta 0.69, 95% CI 0.44, 0.94). After correction for multiple confounders, the CKD (a-Beta 1.58 95%CI 0.00 – 3.22) and operation time (a-Beta 0.67, 95% CI 0.42, 0.92) were consistently associated with the outcome. Conclusions. Our analysis demonstrated a significant role played by the eGFR (as an index of renal function) in influencing the length of hospital stay


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_15 | Pages 43 - 43
1 Nov 2018
Aaron R
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OA pathophysiology has a vascular component consisting of venous stasis resulting in intraosseous hypertension and hypoxia. In response, osteoblasts change their cytokine expression, accelerating bone remodelling and cartilage breakdown consistent with OA. We have characterized circulatory kinetics in OA bone in animal models with dynamic contrast enhanced MRI (DCE-MRI) and . 18. F PET and have demonstrated venous stasis and reduced perfusion that temporally precede and spatially coincide with OA lesions. Osteoblast uptake of . 18. F is consistent with abnormal perfusion, bone remodelling, and severity of OA. Circulatory kinetics with DCE-MRI in humans with OA of the knee exhibit similar venous outflow obstruction. Venous stasis is associated with hypoxia in subchondral bone. As an example of the effects of hypoxia on OA osteoblasts, we have described upregulation of fibrinolytic peptides, but a deficiency in the upregulation of PAI-1, leading to the generation of plasmin by human OA osteoblasts exposed to hypoxia in vitro. Plasmin is a serine protease that has been shown to degrade cartilage in OA. Abnormal circulatory kinetics by DCE-MRI may be an imaging biomarker of OA. Pharmacologic modulation of venous stasis would have a salutary effect on the physicochemical microcirculation of subchondral osteoblasts and the pathophysiology of OA


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_2 | Pages 115 - 115
1 Jan 2017
Ezzat A Chakravarty D Cairns D Craig N
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Newer irreversible oral anticoagulants such as rivaroxaban, a direct factor 10a inhibitor, are increasingly employed to prevent thromboembolic events in atrial fibrillation (AF) patients, and to manage venous thromboembolism (VTE). Unlike warfarin, these agents require no monitoring and involve infrequent dose adjustment. We report the case of a patient treated with rivaroxaban for AF. Patient presented with unprovoked sudden onset right shoulder pain which clinically resembled shoulder haemarthrosis. A single case was anonymised and retrospectively reviewed through examination of clinical and radiographic data. A 70 year old female with known AF presented to Accident and Emergency with sudden onset of right shoulder pain and limited movement, which developed over one hour. The pain was constant, localised to the shoulder and without trauma. Past medical history included severe aortic regurgitation and associated thoracic aortic aneurysm, heart failure, atrial fibrillation and hypertension. Observations were normal upon admission with no haemodynamic compromise or pyrexia. Examining the right shoulder demonstrated distension of shoulder joint capsule, tenderness and a reduced range of movement. Temperature and neurovascular status in the right arm were normal. Investigations upon admission included an INR of 1.2. An anteroposterior right shoulder radiograph showed no evidence of fracture. Patient was managed conservatively with simple oral analgesia. Importantly, rivaroxaban was withheld for 5 days and symptoms resolved. Warfarin therapy was subsequently commenced instead as treatment for AF. Patient was discharged one week later and seen in clinic two weeks post-discharge. A full recovery occurred and with a full range of movement in the right shoulder. In the UK, current National Institute for Health and Care Excellence (NICE) guidelines recommend the use of factor 10a inhibitors, for prevention of stroke in AF patients, and following elective total hip and knee replacement operations to prevent VTE. In turn, rivaroxaban is increasingly prescribed as first line therapy. Whereas warfarin has a documented association with haemarthrosis, there is no primary literature evaluating the incidence of factor 10a therapy associated haemarthrosis. In our case, the unprovoked shoulder haemarthrosis resolved following rivaroxaban cessation. In comparison with warfarin, rivaroxaban is irreversible. With warfarin and a high INR, vitamin K can be used to reverse the anticoagulation. There is no equivalent for rivaroxaban. We suggest further studies into incidence of haemarthrosis associated with oral anticoagulant therapy be undertaken, and treating physicians be aware of such complication


Bone & Joint Research
Vol. 7, Issue 4 | Pages 274 - 281
1 Apr 2018
Collins KH Hart DA Seerattan RA Reimer RA Herzog W

Objectives

Metabolic syndrome and low-grade systemic inflammation are associated with knee osteoarthritis (OA), but the relationships between these factors and OA in other synovial joints are unclear. The aim of this study was to determine if a high-fat/high-sucrose (HFS) diet results in OA-like joint damage in the shoulders, knees, and hips of rats after induction of obesity, and to identify potential joint-specific risks for OA-like changes.

Methods

A total of 16 male Sprague-Dawley rats were allocated to either the diet-induced obesity group (DIO, 40% fat, 45% sucrose, n = 9) or a chow control diet (n = 7) for 12 weeks. At sacrifice, histological assessments of the shoulder, hip, and knee joints were performed. Serum inflammatory mediators and body composition were also evaluated. The total Mankin score for each animal was assessed by adding together the individual Modified Mankin scores across all three joints. Linear regression modelling was conducted to evaluate predictive relationships between serum mediators and total joint damage.


Bone & Joint Research
Vol. 6, Issue 8 | Pages 499 - 505
1 Aug 2017
Morrison RJM Tsang B Fishley W Harper I Joseph JC Reed MR

Objectives

We have increased the dose of tranexamic acid (TXA) in our enhanced total joint recovery protocol at our institution from 15 mg/kg to 30 mg/kg (maximum 2.5 g) as a single, intravenous (IV) dose. We report the clinical effect of this dosage change.

Methods

We retrospectively compared two cohorts of consecutive patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) surgery in our unit between 2008 and 2013. One group received IV TXA 15 mg/kg, maximum 1.2 g, and the other 30 mg/kg, maximum 2.5 g as a single pre-operative dose. The primary outcome for this study was the requirement for blood transfusion within 30 days of surgery. Secondary measures included length of hospital stay, critical care requirements, re-admission rate, medical complications and mortality rates.


Bone & Joint 360
Vol. 6, Issue 5 | Pages 42 - 44
1 Oct 2017
Ross A


Bone & Joint Research
Vol. 6, Issue 2 | Pages 90 - 97
1 Feb 2017
Rajfer RA Kilic A Neviaser AS Schulte LM Hlaing SM Landeros J Ferrini MG Ebramzadeh E Park S

Objectives

We investigated the effects on fracture healing of two up-regulators of inducible nitric oxide synthase (iNOS) in a rat model of an open femoral osteotomy: tadalafil, a phosphodiesterase inhibitor, and the recently reported nutraceutical, COMB-4 (consisting of L-citrulline, Paullinia cupana, ginger and muira puama), given orally for either 14 or 42 days.

Materials and Methods

Unilateral femoral osteotomies were created in 58 male rats and fixed with an intramedullary compression nail. Rats were treated daily either with vehicle, tadalafil or COMB-4. Biomechanical testing of the healed fracture was performed on day 42. The volume, mineral content and bone density of the callus were measured by quantitative CT on days 14 and 42. Expression of iNOS was measured by immunohistochemistry.


Bone & Joint Research
Vol. 5, Issue 6 | Pages 276 - 279
1 Jun 2016
Zhu H Gao Y Wang Y Zhang C

Objectives

Circulating exosomes represent novel biomarkers for multiple diseases. In this study, we investigated whether circulating exosome levels could be used as a diagnostic biomarker for steroid-induced osteonecrosis of the femoral head (ONFH).

Methods

We assessed the serum exosome level of 85 patients with steroid-induced ONFH and 115 healthy donors by Nanosight detection. We then assessed the diagnostic accuracy of serum exosomes by receiver operating characteristic curve analysis.


The Bone & Joint Journal
Vol. 95-B, Issue 11 | Pages 1575 - 1580
1 Nov 2013
Salai M Somjen D Gigi R Yakobson O Katzburg S Dolkart O

We analysed the effects of commonly used medications on human osteoblastic cell activity in vitro, specifically proliferation and tissue mineralisation. A list of medications was retrieved from the records of patients aged > 65 years filed in the database of the largest health maintenance organisation in our country (> two million members). Proliferation and mineralisation assays were performed on the following drugs: rosuvastatin (statin), metformin (antidiabetic), metoprolol (β-blocker), citalopram (selective serotonin reuptake inhibitor [SSRI]), and omeprazole (proton pump inhibitor (PPI)). All tested drugs significantly stimulated DNA synthesis to varying degrees, with rosuvastatin 5 µg/ml being the most effective among them (mean 225% (sd 20)), compared with metformin 10 µg/ml (185% (sd 10)), metoprolol 0.25 µg/ml (190% (sd 20)), citalopram 0.05 µg/ml (150% (sd 10)) and omeprazole 0.001 µg/ml (145% (sd 5)). Metformin and metoprolol (to a small extent) and rosuvastatin (to a much higher extent) inhibited cell mineralisation (85% (sd 5)). Our results indicate the need to evaluate the medications prescribed to patients in terms of their potential action on osteoblasts. Appropriate evaluation and prophylactic treatment (when necessary) might lower the incidence and costs associated with potential medication-induced osteoporosis.

Cite this article: Bone Joint J 2013;95-B:1575–80.


Bone & Joint Research
Vol. 5, Issue 1 | Pages 1 - 10
1 Jan 2016
Burghardt RD Manzotti A Bhave A Paley D Herzenberg JE

Objectives

The purpose of this study was to compare the results and complications of tibial lengthening over an intramedullary nail with treatment using the traditional Ilizarov method.

Methods

In this matched case study, 16 adult patients underwent 19 tibial lengthening over nails (LON) procedures. For the matched case group, 17 patients who underwent 19 Ilizarov tibial lengthenings were retrospectively matched to the LON group.