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Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_2 | Pages 16 - 16
2 Jan 2024
Aydin M Luciani T Mohamed-Ahmed S Yassin M Mustafa K Rashad A
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The aim of this study is to print 3D polycaprolactone (PCL) scaffolds at high and low temperature (HT/LT) combined with salt leaching to induced porosity/larger pore size and improve material degradation without compromising cellular activity of printed scaffolds. PCL solutions with sodium chloride (NaCl) particles either directly printed in LT or were casted, dried, and printed in HT followed by washing in deionized water (DI) to leach out the salt. Micro-Computed tomography (Micro-CT) and scanning electron microscope (SEM) were performed for morphological analysis. The effect of the porosity on the mechanical properties and degradation was evaluated by a tensile test and etching with NaOH, respectively. To evaluate cellular responses, human bone marrow-derived mesenchymal stem/stromal cells (hBMSCs) were cultured on the scaffolds and their viability, attachment, morphology, proliferation, and osteogenic differentiation were assessed. Micro-CT and SEM analysis showed that porosity induced by the salt leaching increased with increasing the salt content in HT, however no change was observed in LT. Structure thickness reduced with elevating NaCl content. Mass loss of scaffolds dramatically increased with elevated porosity in HT. Dog bone-shaped specimens with induced porosity exhibited higher ductility and toughness but less strength and stiffness under the tension in HT whereas they showed decrease in all mechanical properties in LT. All scaffolds showed excellent cytocompatibility. Cells were able to attach on the surface of the scaffolds and grow up to 14 days. Microscopy images of the seeded scaffolds showed substantial increase in the formation of extracellular matrix (ECM) network and elongation of the cells. The study demonstrated the ability of combining 3D printing and particulate leaching together to fabricate porous PCL scaffolds. The scaffolds were successfully printed with various salt content without negatively affecting cell responses. Printing porous thermoplastic polymer could be of great importance for temporary biocompatible implants in bone tissue engineering applications.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_1 | Pages 97 - 97
2 Jan 2024
Mohamed-Ahmed S Yassin M Rashad A Lie S Suliman S Espedal H Idris S Finne-Wistrand A Mustafa K Vindenes H Fristad I
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Mesenchymal stem cells (MSC) have been used for bone regenerative applications as an alternative approach to bone grafting. Selecting the appropriate source of MSC is vital for the success of this therapeutic approach. MSC can be obtained from various tissues, but the most used sources of MSC are Bone marrow (BMSC), followed by adipose tissue (ASC). A donor-matched comparison of these two sources of MSC ensures robust and reliable results.

Despite the similarities in morphology and immunophenotype of donor-matched ASC and BMSC, differences existed in their proliferation and in vitro differentiation potential, particularly osteogenic differentiation that was superior for BMSC, compared to ASC. However, these differences were substantially influenced by donor variations. In vivo, although the upregulated expression of osteogenesis-related genes in both ASC and BMSC, more bone was regenerated in the calvarial defects treated with BMSC compared to ASC, especially during the initial period of healing. According to these findings, compared to ASC, BMSC may result in faster regeneration and healing, when used for bone regenerative applications.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_11 | Pages 30 - 30
1 Nov 2022
Barakat A Ahmed A Ahmed S White H Mangwani J
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Abstract

Background

Distinction between foot and ankle wound healing complications as opposed to infection is crucial for appropriate allocation of antibiotic therapy. Our aim was to evaluate the diagnostic accuracy of white cell count (WCC) and C-reactive protein (CRP) as diagnostic tools for this distinction in the non-diabetic cohort.

Methods

Data were reviewed from a prospectively maintained Infectious Diseases Unit database of 216 patients admitted at Leicester University Hospitals – United Kingdom between July 2014 and February 2020 (68 months). All diabetic patients were excluded. For the infected non-diabetic included patients, we retrospectively retrieved the inflammatory markers (WCCs and CRP) at the time of presentation. Values of CRP 0–10 mg/L and WCC 4.0–11.0 ×109 /L were considered normal.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_11 | Pages 12 - 12
1 Sep 2021
Rose L Williams R Al-Ahmed S Fenner C Fragkakis A Lupu C Ajayi B Bernard J Bishop T Papadakos N Lui DF
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Background

The advent of EOS imaging has offered clinicians the opportunity to image the whole skeleton in the anatomical standing position with a smaller radiation dose than standard spine roentgenograms. It is known as the fifth modality of imaging. Current NICE guidelines do not recommend EOS scans over x-rays citing: “The evidence indicated insufficient patient benefit in terms of radiation dose reduction and increased throughput to justify its cost”.

Methods

We retrospectively reviewed 103 adult and 103 paediatric EOS scans of standing whole spines including shoulders and pelvis for those undergoing investigation for spinal deformity in a tertiary spinal centre in the UK. We matched this against a retrospective control group of 103 adults and 103 children who underwent traditional roentgenograms whole spine imaging at the same centre during the same timeframe. We aimed to compare the average radiation dose of AP and lateral images between the two modalities. We utilised a validated lifetime risk of cancer calculator (www.xrayrisk.com) to estimate the additional mean risk per study.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_11 | Pages 9 - 9
1 Sep 2021
Taha A Houston A Al-Ahmed S Ajayi B Hamdan T Fenner C Fragkakis A Lupu C Bishop T Bernard J Lui D
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Introduction

Pulmonary Tuberculosis (TB) can be detected by sputum cultures. However, Extra Pulmonary Spinal Tuberculosis (EPSTB), diagnosis is challenging as it relies on retrieving a sample. It is usually discovered in the late stages of presentation due to its slow onset and vague early presentation. Difficulty in detecting Mycobacterium Tuberculosis bacteria from specimens is well documented and therefore often leads to culture negative results. Diagnostic imaging is helpful to initiate empirical therapy, but growing incidence of multidrug resistant TB adds further challenges.

Methods

A retrospective analysis of cases from the Infectious Disease (ID) database with Extra Pulmonary Tuberculosis (EPTB) between 1st of January 2015 to 31st of January. Two groups were compared 1) Culture Negative TB (CNTB) and 2) Culture Positive TB (CPTB). Audit number was


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_3 | Pages 17 - 17
1 Apr 2019
Kurian NM Shetty AA Kim SJ Shetty V Ahmed S Trattnig S
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Gel-based autologous chondrocyte implantation (ACI) over the years have shown encouraging results in repairing the articular cartilage. More recently, the use of cultured mesenchymal stem cells (MSC) has represented a promising treatment option with the potential to differentiate and restore the hyaline cartilage in a more efficient way. This study aims to compare the clinical and radiological outcome obtained in these two groups.

Twenty-eight consecutive symptomatic patients diagnosed with full-thickness cartilage defects were assigned to two treatment groups (16 patients cultured bone marrow-derived MSC and 12 patients with gel-type ACI). The MSC group patients underwent microfracture and bone marrow aspiration in the first stage and injection of cultured MSC into the knee in the second stage. Clinical and radiological results were compared at a minimum follow up of five years

There was excellent clinical outcome noted with no statistically significant difference between the two groups. Both ACI and MSC group showed significant improvement of the KOOS, Lysholm and IKDC scores as compared to their preoperative values and this was maintained at 5 years follow up. The average MOCART score for all lesions was also nearly similar in the two groups. The mean T2* relaxation-times for the repair tissue and native cartilage were 27.8 and 30.6 respectively in the ACI group and 28 and 29.6 respectively in the MSC group.

Use of cultured MSC is less invasive, technically simpler and also avoids the need for a second surgery as compared to an ACI technique. With similar encouraging clinical results seen and the proven ability to restore true hyaline cartilage, cultured MSC represent a favorable treatment option in articular cartilage repair.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_3 | Pages 14 - 14
1 Apr 2019
Azhar MS Ahmed S Gogi N Walsh G Chakrabarty G
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Background of study

Total Knee Replacement (TKR) is one of the commonest elective arthroplasty operations. Crepe dressings are used following TKR by most surgeons as it may provide comfort and hemostasis through external pressure however, may reduce early range of motion (ROM). Avoiding crepe dressings after TKR saves operating time, avoids bulky dressings (which may reduce ROM) and allows interventions such as cryotherapy in the early post-operative period. There are no published studies comparing the use of crepe dressing after TKR with an impermeable dressing alone

Materials and Methods

We did a retrospective study, analysing patients who had a TKR with the use of crepe dressings compared with patients who had an impermeable dressing alone. All patients had cruciate retaining PFC Implants through the medial para-patellar approach. We compared ROM (at initial physio contact and on discharge), rate of wound leakage, opioid requirements and duration of inpatient stay.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_15 | Pages 17 - 17
1 Nov 2018
Dalgarno K Benning M Partridge S Tulah A Ahmed S Dickinson A Genever P Pearson R Feichtinger G Loughlin J Ferreira-Duarte A
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This paper reports on a proof of concept project funded by the UK National Council for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), with the aim of developing an in vitro model to recapitulate the human osteoarthritic joint, based on a multiple human cell type co-culture system, for research and drug development in OA. The targets were: (i) the development of a cell culture platform that could produce a mixed stable cell culture of cell types that represent the key components of the human joint: synoviocytes – type I and type II; osteoblasts; osteoclasts; chondrocytes/cartilage or cartilage-like matrix; adipocytes; and immune cells. (ii) demonstration of cell phenotype stability and viability for at least 72 hours. In order to establish the cell culture platform we have developed an eight-channel cell printer, capable of accurately and reliably printing the required cell types to create osteochondral and synovial cell types within a transwell system. Two different sets of cells have been developed and processed using the cell printer: a set based on using an immortalised hTERT MSC line to create osteoblasts, chondrocytes and adipocytes, with commercial cells lines providing the other cell types, and a set obtained from tissue excised during orthopaedic surgery. This gives both a repeatable set of cells with which to undertake mode of action studies, and a bank of cell sets which will be representative of different stages of osteoarthritis. The co-cultures have been immunohistochemically assessed in order to demonstrate maintenance of phenotype.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_17 | Pages 19 - 19
1 Nov 2017
Edwin J Morris D Ahmed S Gooding B Manning P
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The shoulder is the least constrained of all joints of the body and is more susceptible to injury including dislocation. The rate of recurrent instability following primary stabilization procedure at 10 years of follow-up ranged from 3.4 to 35 %. We describe the outcomes of 74 patients who underwent knotless arthroscopic anterior stabilisation using 1.5 mm Labral Tape with 2.9mm Pushlock anchors for primary anterior instability.

We performed a retrospective analysis of patients who underwent surgery for post-traumatic recurrent anterior instability for 2 years by a single surgeon. Patients with glenoid bone loss, >25% Hill Sachs lesion, posterior dislocation, paediatric age group and multidirectional instability were excluded from this study. Over 90% of our case mix underwent the procedure under regional block anaesthesia and was discharged on the same day. The surgical technique and post-operative physiotherapy was as per standard protocol. Outcomes were measured at 6 months and 12 months. Of the 74 patients in our study, we lost 5 patients to follow up. Outcomes were measured using the Oxford Shoulder Score apart from clinical assessment including the range of motion.

We noted good to excellent outcomes in 66 cases using the Oxford Instability Scores. All patients achieved almost full range of motion at the end of one year. Our cumulative Oxford Instability Score (OIS) preoperatively was 24.72 and postoperatively was 43.09. The Pearson correlation was .28. The t Critical two-tail was 2.07 observing the difference between the means of the OIS. Complications included recurrent dislocation in 2 patients following re-injury and failure of procedure due to recurrent instability requiring an open bone block procedure in one case. We had no reported failures due to knot slippage or anchor pull-out.

We publish the largest case series using this implant with distinct advantages of combining a small bio absorbable implant with flat braided, and high-strength polyethylene tape to diminish the concern for knot migration and abrasive chondral injury with the potential for earlier rehabilitation and a wider footprint of labral compression with comparative outcomes using standard techniques. Our results demonstrate comparable and superior results to conventional suture knot techniques for labral stabilization.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_17 | Pages 12 - 12
1 Nov 2017
Ahmed S Girgis E Saad A Edwin J Compson J
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Background

Non-operative cases of mallet finger can be followed up by the hand therapists. Both trust and national policies encourage appropriate indication for follow-up in fracture clinic & cost-effective approach without affecting the patient care.

Aims

To reduce unnecessary fracture clinic follow up for Mallet finger injuries.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_17 | Pages 9 - 9
1 Nov 2017
Shetty A Kim S Alva K Ahmed S
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Introduction

We describe five results of a novel single stage arthroscopic technique for the treatment of articular cartilage defects of the knee. This involves micro drilling and application of Atelo-collagen (Coltrix) and fibrin gel scaffold.

Materials and Method

The preclinical study involved two groups of rabbits treated with micro-drilling, and micro-drilling with Atelo-collagen and fibrin gel. New cartilage was subjected to staining with H&E for tissue morphology, toluidine blue (collagen) and safranin O (GAG), immunohistochemistry with antibodies for collagen type I and II, and scanning and transmission electron microscopy to analyse the microstructural morphologies. The micro-drilling with Atelo-collagen, fibrin gel scored better than the micro-drilling alone.

Patients (n=30) with symptomatic ICRS grade III/IV chondral defects (lesion size 2–8cm2) are recruited for this prospective study. The surgical procedure involved micro-drilling and application of Atelo–collagen and fibrin gel under CO2 insufflation. Patients underwent morphological evaluation with MRI (T2*-mapping and d-GEMRIC scans). Clinical assessment was done with Lysholm, IKDC and KOOS scores. Radiological assessment was performed with MOCART score.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_15 | Pages 13 - 13
1 Sep 2016
Mitchell P Viswanath A Obi N Ahmed S Latimer M
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The aim of this study was determine if the detection of pathology in children with a limp can be optimised by screening with blood tests for raised inflammatory markers.

The entry criteria for the study were children (0–15 years) presenting to our hospital Emergency Department from 2012–2015 with a non-traumatic limp or pseudoparalysis of a limb, and no sign of fracture or malignancy on plain radiographs. ESR and CRP blood tests were performed along with other standard investigations. Children with ESR or CRP over 10 underwent MRI scan of their area of pain or tendernesss, with those under 7 years old having general anaesthetic. MRI provided the diagnosis in cases of osteomyelitis, pyomyositis, fasciitis, cellulitis, discitis, as well as non-infective conditions such as malignancy and fracture not visible on plain radiographs. Where a joint effusion was present, the diagnosis of septic arthritis was made from organisms cultured following surgical drainage, or high white cell count in joint fluid if no organisms were cultured. The study was completed once data from 100 consecutive children was available.

64% of children had an infective cause for their symptoms (osteomyelitis, septic arthritis, pyomyositis, fasciitis, cellulitis or discitis). A further 11% had positive findings on MRI from non-infective causes (juvenile idiopathic arthritis, cancer, or occult fracture). The remaining 25% had either a normal scan, or transient synovitis. ESR was a more sensitive marker than CRP, since ESR was raised in 97% of those with abnormal scans, but CRP in only 70%. There were no complications from any of the GA MRI scans. Conclusion: This shows that MRI imaging of all children with a limp and either raised ESR or CRP is a sensitive method to minimise the chance of missing important pathology in this group, and is not wasteful of MRI resources.


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_10 | Pages 18 - 18
1 Oct 2015
Bawale R Samsani SR Jain S Joshi A Ahmed S Singh B Mohanlal P Pillai D Prasad R
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Background

Revision surgery for a failed metal on metal (MoM) hip arthroplasty is often unpredictable and challenging due to associated massive soft tissue and bony lesions. We present the analysis and early outcomes of revision surgery in failed MoM hip arthroplasties at our institution.

Methods

We have retrospectively analysed the findings and outcomes of revision surgery in 61 failed MoM hip arthroplasties performed between 2009 and 2014. These patients were identified in the special MoM hip surveillance pathway. All these patients underwent clinical assessment and relevant investigations. Intra-operative and histopathological findings were analysed.


The Bone & Joint Journal
Vol. 95-B, Issue 4 | Pages 467 - 471
1 Apr 2013
Sandiford N Doctor C Rajaratnam SS Ahmed S East DJ Miles K Butler-Manuel A Shepperd JAN

We present the extended follow-up (≥ 20 years) of a series of fully hydroxyapatite-coated femoral components used in 72 primary total hip replacements (THRs). Earlier results of this cohort have been previously published. All procedures were performed between 1986 and 1991. The series involved 45 women and 15 men with 12 bilateral procedures. Their mean age at the time of surgery was 60 years (46 to 80) and the mean duration of follow-up was 22.5 years (20 to 25). At final follow-up, the mean Merle d’Aubigné and Postel hip scores were 5.5 (4.5 to 6), 3.8 (3.5 to 5) and 3.3 (3.0 to 5.0) for pain, mobility and function, respectively. Of the patients 92% were very satisfied at the time of final follow-up.

There were seven revisions: six of the acetabular component for aseptic loosening and one of both the stem and the acetabular component for loosening due to deep infection. The survival of this prosthesis at 22.5 years with revision for any reason as the endpoint was 91.7% (95% confidence interval (CI) 84 to 99). Survival with aseptic loosening of the stem as the endpoint was 100% (95% CI 90 to 100).

This prosthesis provides pain relief in the long term. Survival of this component is comparable to the best results for primary THR with any means of fixation.

Cite this article: Bone Joint J 2013;95-B:467–71.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 99 - 99
1 Mar 2013
Sabry FY Klika A Buller L Ahmed S Szubski C Barsoum W
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Background

Two-stage revision is considered the gold standard for treatment of knee prosthetic joint infections. Current guidelines for selecting the most appropriate procedure to eradicate knee prosthetic joint infections are based upon the duration of symptoms, the condition of the implant and soft tissue evaluated during surgery and the infecting organism. A more robust tool to identify candidates for two-stage revision and who are at high risk for treatment failure might improve preoperative risk assessment and increase a surgeon's index of suspicion, resulting in closer monitoring, optimization of risk factors for failure and more aggressive management of those patients who are predicted to fail.

Methods

Charts from 3,809 revision total joint arthroplasties were reviewed. Demographic data, clinical data and disease follow-up on 314 patients with infected total knee arthroplasty treated with two-stage revision were collected. Univariate analyses were performed to determine which variables were independently associated with failure of the procedure to eradicate the prosthetic joint infections. Cox regression was used to construct a model predicting the probability of treatment failure and the results were used to generate a nomogram which was internally validated using bootstrapping.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_7 | Pages 8 - 8
1 Feb 2013
Lahoti O Ahmed S Rashid A
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Purpose of the study

We conducted a study to assess the accuracy of Spatial CAD software in computing the mounting and deformity parameters.

Methods and end results

We mounted a two-ring construct on a sawbone tibia and accurately measured the mounting parameters of this frame. Then we obtained three sets of x-rays – orthogonal without magnification marker, orthogonal with magnification marker placed at the level of the bone and non orthogonal views – and put these images through software and obtained mounting and deformity parameters.

Results were independently assessed and we found that the Spatial CAD™ software was accurate within 1 mm and 1 degree when orthogonal images with marker sphere placed at the bone level were used. Non-orthogonal images, with marker sphere, yielded accurate axial frame offset but other mounting parameters were at least 6 mm more than the actual measurements. Understandably angular measurements were different. In the third set of films we used frame hardware – Rancho Cube width (12 mm) as a calibrator. Since the cube was not in the same plane as the bone all measurements were way off actual measurements.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_1 | Pages 24 - 24
1 Jan 2013
Sandiford N Doctor C Ahmed S East D Miles K Butler-Manuel A Shepperd J
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Introduction

The ideal method of fixation for femoral components in total hip arthroplasty (THA) is unknown. While good results have been reported for cemented and uncemented components, there is relatively little published prospective data with twenty years or more of follow up.

Results of the Furlong femoral component have been presented at an average of 17 years follow up. We have extended this follow up period to an average of 22.5 years with a minimum of 22 years and a maximum of 25 years.

Methods

This study included all patients treated using the Furlong femoral component between 1986 and 1991. Patients were reviewed preoperatively and then at 6, 12, 26 and 52 weeks post operatively and annually thereafter.

They were assessed clinically and radiographically and the Merle d'Aubigne Postel hip score was calculated at each visit. A Visual Analog Score (VAS) was also recorded to assess patient satisfaction with their procedure. A Kaplan Meier survival analysis was performed.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXIX | Pages 60 - 60
1 Jul 2012
Colaço H Davidson J Pekicten B Ahmed S Skyrme A Armitage A Rajaratnam S
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Purpose

This study investigates the effect of early tourniquet release on range of flexion following total knee replacement, and the influence of anticoagulation with Rivaroxaban and Clexane (Enoxaparin).

Method

78 patients were included in the study, who underwent unilateral primary total knee replacement (TKR) in our department under the care of two specialist knee surgeons over a 12 month period. 27 patients underwent TKR with early release of the tourniquet and haemostasis, prior to closure of quadriceps layer: 22 were anticoagulated with Rivaroxaban (GROUP ER), 15 with the low molecular weight heparin Clexane (GROUP EC). Over the same time period, 41 patients TKR with late release of the tourniquet, following closure and bandaging: 13 were anticoagulated with Rivaroxaban (GROUP LR), 28 with Clexane (GROUP LC). A standardised operative technique was employed, and all patients received an AGC (Biomet) PCL-retaining prostheses. Outcome was assessed with range of flexion at 12 weeks postoperatively.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_III | Pages 81 - 81
1 Feb 2012
Lakshmanan P Ahmed S Dixit V Reed M Sher J
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Background

Percutaneous K-wire fixation is a well-recognised and often performed method of stabilisation for distal radius fractures. However, there is paucity in the literature regarding the infection rate after percutaneous K-wire fixation for distal radius fractures.

Aims

To analyse the rate and severity of infection after percutaneous K-wire fixation for distal radius fractures.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_I | Pages 7 - 7
1 Jan 2011
Hajipour L Gulihar A Ahmed S Dias J Ullah A
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Treatment of a partial laceration in zone two of a flexor tendon remains controversial. The intact part of the tendon can sustain forces of normal un-resisted motion, and repaired partially treated tendons can actually be weaker than un-repaired ones. Trimming these lacerations has been shown to be beneficial in partially lacerated tendons with triggering or entrapment.

The purpose of this study is to observe the behaviour of a partially lacerated and subsequently trimmed tendon under strain, and measure their friction coefficient at different flexion angle and load. Ten long flexor tendons from long digit of turkey foot, along with the equivalent of A2 pulley were used. All experiments were carried out for intact, lacerated (50%) and trimmed tendon at 10, 30, 50 and 70 degrees of flexion and two load settings of 200 and 400g.

The friction forces were measured by the difference between the two load transducers and the friction coefficient was measured using this formula, μ = Ln[(F2/F1)]/Ø.

Friction coefficient (μ), Tension forces (F2 and F1), arc of tendon and pulley contact (Ø).

Results: Friction coefficient increased significantly by three folds (0.3) after laceration compare with intact tendon (0.12) at both loads. This was reduced significantly after trimming the tendon but the friction coefficient was still approximately twice the value of the intact tendon (0.2).

Triggering was noticed in all tendon lacerations. Triggering was reduced after trimming in 10 and 30 degrees of flexion but increased markedly at 50 and 70 degrees of flexion associated with tendon fragmentation at the trimmed area.

Trimming partially lacerated flexor tendons will reduce the gliding resistance of the tendon through the pulley but this can lead to further fragmentation and triggering at higher flexion degrees and loads.