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Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_18 | Pages 17 - 17
1 Dec 2023
Sharma N George A Hampton M Barnett A
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Introduction

Trochleoplasty is an effective surgical procedure for patients with severe trochlear dysplasia and recurrent patella instability. Previous work has suggested patients demonstrate early improvements in knee function and quality of life. However, concerns regarding longer term outcomes due to the development of stiffness and patellofemoral osteoarthritis remain a concern for these patients. Our aim was to assess mid-term patient-reported outcome and quality of life measures for trochleoplasty performed at a single centre for severe trochlear dysplasia.

Methods

Retrospective review of 28 knees (23 patients) having undergone trochleoplasty for severe trochlear dysplasia were reviewed. Due to the non-parametric nature of the data, median and interquartile range (IQR) were determined for pre-operative and mid-term follow-up scores. Statistically significant differences between groups were assessed using paired Wilcoxon-signed rank test with statistical significance set at p<0.05. Data were analysed using a statistical software package (IBM® SPSS® Statistics 26.0).


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_4 | Pages 113 - 113
1 Mar 2021
George A Ellis M Gill R
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Hypoxic Inducible Factor and Hypoxic mimicking agents (HMA) trigger the initiation and promotion of angiogenic-osteogenic cascade events. However, there has been paucity of studies investigating how HIF could be over expressed under chronic hypoxic conditions akin to that seen in sickle cell disease patients to help form a template for tackling the matter of macrocellular avascular necrosis. Angiogenesis and osteogenesis are tightly coupled during bone development and regeneration, and the hypoxia-inducible factor-1 alpha (HIF-1) pathway has been identified as a key component in this process studies have shown. There are still no established experimental models showing how this knowledge can be used for the evaluation of bone implant integration and suggest ways of improving osseointegration in sickle cell disease patients with hip arthroplasty and thereby prevent increased implant loosening. The aim of this study is to help develop an in vitro experimental model which would mimic the in vivo pathologic state in the bone marrow of sickle cell disease patients. It also seeks to establish if the hypoxic inducible factor (HIF) could be over expressed in vitro and thus enhancing osseointegration. MG63 osteoblastic cells were cultured under normoxia and hypoxic conditions (20%; and 1% oxygen saturation) for 48 and 72 hours. Cobalt chloride was introduced to the samples in order to mimic true hypoxia. Cells cultured under normoxic conditions and without cobalt chloride was used as the control in this study. The expression of the hypoxic inducible factor was assessed using the reverse transcriptase qualitative polymerase chain reaction (RT-qPCR). There was increased expression of HIF1-alpha at 72hours as compared to 48hours under the various conditions. The level of expression of HIF increased from 48hrs (mean rank= 4.60) to 72hrs (mean rank =5.60) but this difference was not statistically significant, X2(1) = 0.24, p =0.625. The mean rank fold change of HIF in hypoxic samples decreased compared to the normoxic samples but this difference was not statistically significant, X2(1) = 0.54, p= 0.462. Therefore, the expression of HIF is only increased with prolonged hypoxia as seen in the 72hours samples. The expression of HIF increased in samples with CoCl2 (mean rank=5.17), compared with samples without CoCl2 (mean rank 4.67), however this was not statistically significant, X2(1) = 0.067, p=0.796, p value > 0.05. The over expression of HIF was achieved within a few days (72hours) with the introduction of Cobalt Chloride, which is a mimetic for hypoxia similar to the in vivo environment in sickle cell disease patients. This is an in vitro model which could help investigate osseointergation in such pathologic bone conditions.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_16 | Pages 101 - 101
1 Nov 2018
George A Ellis M Gill R
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It is well documented that implant loosening rate in sickle cell disease patients is higher than that seen in patients with hip arthroplasty from other indications. The Hypoxic inducible factor(HIF) - is activated in the microcellular hypoxic environment and this through a cascade of other enzymatic reactions promotes the activity of other factors and further help enhance angiogenesis and osteogenesis. The aim of this study was to investigate and propose a potential model for investigating osseointegration in a hypoxic microcellular environment using osteoblasts(MG63).

Human MG63 osteoblastic cells were cultured under normoxia and hypoxic conditions (20%; and 1% oxygen saturation) for 72 hours under two different condition- with and without cobalt chloride. The samples cultured under normoxic condtions without cobalt chloride acted as control. Using qualitative polymerase chain reaction-(qPCR) - HIF expression was assessed under the above conditions in relation to the control.

The results showed there was significant expression of the HIF 1 alpha protein under hypoxic condition with cobalt chloride in comparison with the control samples- all at 72hours incubation. Mann-Whitney U test was used to deduce level of significance of fold change.(p=0.002; <0.05). This was deemed as being a significant difference in the level of expression of HIF compared to the control.

The results show that the hypoxic inducible factor can be expressed using the above tested

experimental invitro-model with significant results which can be a foundation for further research into improving hip implant prosthesis design to help enhance osseo-integration in sickle cell disease patient with AVN.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 15 - 15
1 Sep 2012
George A Hassaballa M Artz N Alhammali T Robinson J Porteus A Murray J
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Introduction

The legion knee revision system was designed as a follow and improvement to the Genesis II knee system- allowing for a surgeon directed femoral rotation as opposed to the in-built femoral rotation in the previous system.

This is a prospective review of consecutive patients who underwent knee revision surgery using the legion knee system.

Methods

Clinical and functional assessments were carried out preoperatively, one year and 2 years post op. Radiographic evaluation was done at 1 and 2years follow up. Standard knee scoring systems (American Knee Scores-AKS, and Oxford score were used for the clinical and functional evaluation of these patients. The WOMAC score was also used to assess for pain, stiffness and social function in these patients. The radiographic assessment included review of standing AP, lateral and skyline views. Figgie's method was used to measure the joint line reproduction. A difference of 5 mm (pre = op/post-op) was deemed satisfactory.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXX | Pages 10 - 10
1 Jul 2012
George A Grimer R
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Introduction

Current practice in the UK is to perform clinical follow up and CXR on patients with sarcomas with the use of cross-sectional imaging reserved for high clinical suspicion of recurrence. We aimed to assess the effectiveness of this policy by investigating patients who developed local recurrence (LR) after previous treatment of a bone or soft tissue sarcoma (STS). Additionally, we aimed to determine whether size and extent of LR at diagnosis of recurrence affected subsequent management.

Method

We reviewed clinical records and imaging of all patients in the previous 5 years (01/01/2005–01/07/2010) with diagnosed LR to investigate: how it was diagnosed, site and size of recurrence and management. A value judgement was made as to whether earlier diagnosis may have altered treatment and/or outcome.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXIX | Pages 77 - 77
1 Jul 2012
George A Hassaballa M Alhammali T Robinson J Murray J Porteus A
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PURPOSE

The aim of this study was to study the short-term outcome of a contemporary modular revision knee system used in our centre for managing Knee revision arthroplasty

METHODS

Preoperative, one and two years follow up scores and radiographic analysis were recorded from 72 consecutive knee revision cases performed between 2006 and 2008. Outcome measures included the American Knee Society (AKSS), Oxford (OKS) and WOMAC scores and range of motion. The radiographic assessment included review of standing AP, lateral and skyline views. Figgie's method was used to measure the joint line reproduction. A difference of 5 mm (pre=op/post-op) was deemed satisfactory.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_III | Pages 342 - 342
1 Mar 2004
Macdonald A Pozo J George A
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Aims: High evacuation pressure is known to increase drained blood loss following uncemented total knee replacements (TKRs). However, the effect of different evacuation pressures on drained loss or total blood loss in cemented TKRñs is unknown. We set out to investigate this effect. Methods: One hundred patients undergoing cemented TKRñs were randomised to receive high or low-pressure suction drains after surgery. The following were observed:-

The volume of blood evacuated from the knee joint,

The calculated total blood loss,

Time to discharge, range of movement and incidence of wound problems.

Results: Greater drainage volumes were seen with the higher evacuation pressures. However, total blood loss from the circulating volume was not statistically different between the two groups. No difference was seen in morbidity or clinical outcome. Drained volumes were substantially less than published values for uncemented TKRs. Conclusions: For a given drop in total blood volume, the high-pressure drains were more efþcient in evacuating haemarthrosis. However, the lower pressures drains demonstrated no increase in morbidity or worsened clinical outcome. The relevance of these þndings in the context of autologous salvage drainage systems, which operate at similar low-pressures to avoid haemolysis, is presented.