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Khan WS, Pyarasani S, Asmatulu R. Reinforcing antibacterial hydrogels through electrospun nanofiber layers for soft tissue engineering. J Polym Res 2020. [DOI: 10.1007/s10965-020-02354-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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2
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Mandadi GK, Asmatulu R, Khan WS, Asmatulu E. Fast and affordable recycling approach to electronic waste above the melting point using induction heat combined with centrifugal forces. ASIA-PAC J CHEM ENG 2020. [DOI: 10.1002/apj.2483] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Gopi K. Mandadi
- Department of Mechanical EngineeringWichita State University Wichita KS 67260 United States
| | - Ramazan Asmatulu
- Department of Mechanical EngineeringWichita State University Wichita KS 67260 United States
| | - Waseem S. Khan
- Department of Mechanical and Mechatronics EngineeringFujairah Men's College, Higher Colleges of Technology Fujairah United Arab Emirates
| | - Eylem Asmatulu
- Department of Mechanical EngineeringWichita State University Wichita KS 67260 United States
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3
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Alarifi IM, Khan WS, Asmatulu R. Synthesis of electrospun polyacrylonitrile- derived carbon fibers and comparison of properties with bulk form. PLoS One 2018; 13:e0201345. [PMID: 30091992 PMCID: PMC6084898 DOI: 10.1371/journal.pone.0201345] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Accepted: 07/14/2018] [Indexed: 11/18/2022] Open
Abstract
This study deals with the fabrication of polyacrylonitrile (PAN) nanofibers via an electrospinning process followed by stabilizing and carbonization in order to remove all non-carboneous matter and ensure a pure carboneous material. The as-spun PAN fibers were stabilized in air at 270°C for one hour and then carbonized at 750, 850, and 950°C in an inert atmosphere (argon) for another one hour. Differential scanning calorimetry and Raman spectroscopy were employed to determine the thermal and chemical properties of PAN. Surface features and morphologies of PAN-derived carbon nanofibers were investigated by means of scanning electron microscopy (SEM). SEM micrograms showed that fiber diameters were reduced after carbonization due to evolution of toxic gases and dehydrogenation. The Raman spectra of carbonized fibers manifested D/G peaks. The Raman spectroscopy peaks of 1100 and 500 cm-1 manifested the formation of γ phase and another peak at 900 cm-1 manifested the formation of α-phase. The water contact angle measurement of carbonized PAN fibers indicated that the nanofibers were superhydrophobic (θ > 150o) due to the formation of bumpy and pitted surface after carbonization. In DSC experiment, the stabilized fibers showed a broad exothermic peak at 308°C due to cyclization process. The mechanical andThermal analysis was used to ascertain mechanical properties of carbonized PAN fibers. PAN-derived carbon nanofibers possess excellent physica and mechanical properties and therefore, they may be suitable for many industrial applications such as energy, biomedical, and aerospace.
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Affiliation(s)
- Ibrahim M. Alarifi
- Department of Mechanical and Industrial Engineering, Majmaah University, Majmaah, Saudi Arabia
- * E-mail:
| | - Waseem S. Khan
- Department of Mechanical Engineering, Higher Colleges of Technology, Dubai Men’s College, Dubai, UAE
| | - Ramazan Asmatulu
- Department of Mechanical Engineering, Wichita State University, Wichita, United States of America
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4
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Szostakowski B, Smitham P, Khan WS. Plaster of Paris-Short History of Casting and Injured Limb Immobilzation. Open Orthop J 2017; 11:291-296. [PMID: 28567158 PMCID: PMC5420179 DOI: 10.2174/1874325001711010291] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 03/02/2017] [Accepted: 03/09/2017] [Indexed: 12/03/2022] Open
Abstract
Various materials have been used since ancient times to help immobilise fractures. In this review, we discuss the history and developments of these materials as well as plaster of Paris. There has been a recent trend away from non-operative management of fractures, and skills in the use of plaster of Paris are declining. For the successful treatment of patients, it is important to appreciate how plaster works, how it should be used, and what can go wrong. In this review, we also discuss principles of applications and complications of plaster of Paris.
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Affiliation(s)
- B Szostakowski
- University College London Institute of Orthopaedics and Musculoskeletal Science, Royal National Orthopaedic Hospital, Stanmore, HA7 4LP, London, UK
| | - P Smitham
- University College London Institute of Orthopaedics and Musculoskeletal Science, Royal National Orthopaedic Hospital, Stanmore, HA7 4LP, London, UK
| | - W S Khan
- University College London Institute of Orthopaedics and Musculoskeletal Science, Royal National Orthopaedic Hospital, Stanmore, HA7 4LP, London, UK
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5
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Khan WS, Smart A. Outcome of surgery for chronic patellar tendinopathy: A systematic review. Acta Orthop Belg 2016; 82:610-326. [PMID: 29119904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
There is no consensus on how to best surgically treat chronic patellar tendinopathy. This systematic review investigates the surgical treatment for chronic patellar tendinopathy, and the outcomes. A database search was performed to identify all relevant articles, to which exclusion criteria were then applied. Data was extracted from 24 studies, and the outcomes were then systematically reviewed. The results showed that the success rate of surgery for patellar tendinopathy is generally over 77%. Return to sports rates are better for proximal tendon patients who undergo bony procedures. Patients return to sports faster if they undergo arthroscopic procedures, and fewer complications are described. Studies that did not involve any procedure on the proximal tendon did not produce a different result to studies where the tendon was operated on. We found no effect of post-operative immobilisation on outcome. Based on the included studies, surgery gives satisfactory results in the treatment of patellar tendinopathy. There is a lack of high-quality evidence on the effects of surgery and post-operative rehabilitation regime on chronic patellar tendinopathy, as well as lack of objective outcome measures.
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6
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Alarifi IM, Alharbi A, Khan WS, Rahman AKMS, Asmatulu R. Mechanical and Thermal Properties of Carbonized PAN Nanofibers Cohesively Attached to Surface of Carbon Fiber Reinforced Composites. ACTA ACUST UNITED AC 2016. [DOI: 10.1002/masy.201650003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ibrahim M. Alarifi
- Department of Mechanical Engineering; Wichita State University; 1845 Fairmount Street Wichita KS 67260 USA
| | - Abdulaziz Alharbi
- Department of Mechanical Engineering; Wichita State University; 1845 Fairmount Street Wichita KS 67260 USA
| | - Waseem S. Khan
- Department of Mechanical and Industrial Engineering; Majmaah University; Majmaah Saudi Arabia
| | - AKM Samsur Rahman
- Department of Mechanical Engineering; Colorado State University; Fort Collins CO 80523 USA
| | - Ramazan Asmatulu
- Department of Mechanical Engineering; Wichita State University; 1845 Fairmount Street Wichita KS 67260 USA
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7
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Wheelton A, Mace J, Khan WS, Anand S. Biomaterials and Fabrication to Optimise Scaffold Properties for Musculoskeletal Tissue Engineering. Curr Stem Cell Res Ther 2016:CSCRT-EPUB-76503. [PMID: 27297035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 05/01/2016] [Indexed: 06/06/2023]
Abstract
Tissue engineering has emerged as a promising scientific field potentially yielding in vitro developed tissue to replace degenerative or injured tissues in vivo, thus avoiding the donor site morbidity associated with reconstructive surgery. Integral to the process is the role of scaffolds and the biomaterials used to form them. This review explores the concept of scaffold based tissue engineering and design considerations. The scaffold needs to have certain mechanical and architectural properties, it needs to be biocompatible and biodegradable, and allow combination with bioactive molecules. We also discuss scaffolding techniques, different biomaterial options and fabrication technologies, and future areas of development.
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Affiliation(s)
| | | | - W S Khan
- Clinical Lecturer, University College London Institute of Orthopaedics and Musculoskeletal Science, Royal National Orthopaedic Hospital, Stanmore, London, HA7 4LP, UK.
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8
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Pengas IP, Khan WS, Bennett CA, Rankin KS. Impact of Weekend Physiotherapy Service on the Cost Effectiveness of Elective Orthopaedic Hip and Knee Arthroplasty. Open Orthop J 2015; 9:515-9. [PMID: 26587071 PMCID: PMC4645972 DOI: 10.2174/1874325001509010515] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Revised: 05/31/2015] [Accepted: 06/01/2015] [Indexed: 12/03/2022] Open
Abstract
We performed a prospective correlational study to evaluate the efficiency and cost effectiveness of weekend
physiotherapy in accelerating rehabilitation, reducing hospital stay as well as hospital costs for joint arthroplasty patients
in a busy Scottish district general hospital. Patients that underwent elective hip (470) and knee (321) arthroplasty were
analysed over a 12 month period. A four month period with weekend physiotherapy provision was arranged to ascertain
its effectiveness on the length of stay and the achievement of set physiotherapy milestones. Data collected included length
of stay and progression in a defined set of physiotherapy milestones. The relationship between time to discharge,
mobilisation with sticks, straight leg raise, 90º knee flexion and cost effectiveness of service were used to determine the
correlation, and analysis of the interactions of these factors separately. Our Outcome data demonstrate a statistical
significance for the time to mobilisation with two sticks for hip (p=0.0030) and knee (p= 0.0037) arthroplasty patients.
There was a trend towards earlier discharge times for all patients receiving weekend physiotherapy, but this was not
statistically significant. We conclude that the provision of a continuous programme of weekend physiotherapy for all
arthroplasty patients has the potential benefit of a quicker rehabilitation that would results in a cost saving.
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Affiliation(s)
- I P Pengas
- Department of Orthopaedics, Perth Royal Infirmary, Perth, Scotland PH1 1NX, UK
| | - W S Khan
- University College London Institute of Orthopaedics & Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, London HA7 4LP, UK
| | - C A Bennett
- Department of Physiotherapy, Perth Royal Infirmary, Perth, Scotland PH1 1NX, UK
| | - K S Rankin
- Department of Orthopaedics, Perth Royal Infirmary, Perth, Scotland PH1 1NX, UK
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9
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Rashid MA, Parnell M, Khan WS, Khan A. First Metatarsalphalangeal Joint Arthrodesis: A Retrospective Comparison of Two Methods of Fixation. Open Orthop J 2015; 9:480-2. [PMID: 26587065 PMCID: PMC4645895 DOI: 10.2174/1874325001509010480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 03/03/2015] [Accepted: 05/22/2015] [Indexed: 12/02/2022] Open
Abstract
First metatarsalphalangeal joint arthrodesis is a well established and successful treatment; however there still remains controversy over the best choice of construct. We performed a retrospective study of patients undergoing first metatarsalphalangeal fusion over eighteen months (n=52) using either dorsal non-locking plate with additional compression lag screw fixation or dorsal non-locking plate alone. We found when assessing clinical criteria, patients with dorsal non-locking plates and additional compression lag screw fixation had a significantly higher rate of fusion (100% vs 77.8%), significantly higher rate of fusion within the first two months (55.6% vs 83.3%), significantly earlier time to fusion (52.2 days vs 75.6 days), and significantly lower rate of non-union (0% vs 22.2%). When blindly assessing radiographic criteria, the patients treated with the plate and compression screw had a significantly higher rate of fusion and lower rate of non-union (0% vs 33%). There was no statistically significant difference between the frequencies of complications in the groups. We believe that the interfragmentary compression is a crucial factor in achieving good union rates and recommend the use of non-locking pre-contoured plating with additional interfragmentary compression screw as the fixation method of choice for these procedures.
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Affiliation(s)
- M A Rashid
- Department of Trauma and Orthopaedics, Southend University Hospital NHS Foundation Trust, Essex, SS0 0RY, UK
| | - M Parnell
- Department of Trauma and Orthopaedics, Southend University Hospital NHS Foundation Trust, Essex, SS0 0RY, UK
| | - W S Khan
- Department of Trauma and Orthopaedics, Southend University Hospital NHS Foundation Trust, Essex, SS0 0RY, UK
| | - A Khan
- Department of Trauma and Orthopaedics, Southend University Hospital NHS Foundation Trust, Essex, SS0 0RY, UK
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10
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Affiliation(s)
- W S Khan
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, Middlesex, HA7 4LP, UK
| | - U G Longo
- Department of Orthopaedic and Trauma Surgery, Campus Bio-Medico University, Via Alvaro del Portillo, 200, 00128 Trigoria, Rome, Italy
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11
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Chew E, Khan WS, Agarwal S, Morgan-Jones R. Single Stage Knee Arthroplasty Revision Surgery: A Systematic Review of the Literature. Open Orthop J 2015; 9:504-10. [PMID: 26587070 PMCID: PMC4645866 DOI: 10.2174/1874325001509010504] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 05/23/2015] [Accepted: 05/27/2015] [Indexed: 01/04/2023] Open
Abstract
Total Knee Arthroplasty is an increasingly common procedure and revision surgery, particularly for infection, is associated with significant morbidity and healthcare costs. The current gold standard is a two stage revision procedure but single stage revision is increasingly being used in some departments to improve patient outcomes. We conducted a systematic review of the literature to determine the up-to-date evidence underlying the use of a single stage knee approach in revision surgery. A total of 12 studies were included in this review amounting to 433 revision surgeries. This is the largest review of single stage knee revision surgery. The procedures described were heterogenous and included the 'two-in-one' technique as well as other single stage revision procedures. There were also differences in implants and antibiotic regimens. The mean re-infection rates described in 10 studies was 9.4% (range 0-19.2%) after a mean follow-up of 40.3 months (range 7-180 months). The re-infection rates in the studies published over the last 30 years are falling, and this is not accounted for by any significant change in duration of follow-up during this period. The outcome scores varied, but patients generally showed an improvement. The Knee Society Score and the Oxford Knee Score were the most commonly used in five and three studies respectively. We conclude that the current evidence for single stage revision is variable and there is a lack of good quality evidence to address whether single stage revisions is thorough enough to eradicate deep infection and is able to restore adequate function. There is a need for larger prospective studies with standardised procedures and protocol, and with adequate follow-up. Till then, patients considered for a single stage approach should be thoroughly assessed and the surgery should be performed by a senior surgeon with experience in single stage knee revisions.
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Affiliation(s)
- E Chew
- Department of Trauma and Orthopaedics, Royal Free Hospital, Hampstead, London, NW3 2QG, UK
| | - W S Khan
- Cardiff & Vale Orthopaedic Centre, Llandough University Hospital, Cardiff & Vale NHS Trust, Cardiff, CF5 2LD, UK
| | - S Agarwal
- Cardiff & Vale Orthopaedic Centre, Llandough University Hospital, Cardiff & Vale NHS Trust, Cardiff, CF5 2LD, UK
| | - R Morgan-Jones
- Cardiff & Vale Orthopaedic Centre, Llandough University Hospital, Cardiff & Vale NHS Trust, Cardiff, CF5 2LD, UK
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12
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James M, Khan WS, Nannaparaju MR, Bhamra JS, Morgan-Jones R. Current Evidence for the Use of Laminar Flow in Reducing Infection Rates in Total Joint Arthroplasty. Open Orthop J 2015; 9:495-8. [PMID: 26587068 PMCID: PMC4645891 DOI: 10.2174/1874325001509010495] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 04/23/2015] [Accepted: 05/22/2015] [Indexed: 11/22/2022] Open
Abstract
Since the introduction of laminar air flow in orthopaedic theatres by Sir John Charnley, it has widely become accepted as the standard during orthopaedic procedures such as joint arthroplasty. We present a review of available current literature for the use of laminar flow operating theatre ventilation during total joint arthroplasty and examines the effectiveness of laminar flow ventilated operating theatres in preventing post-operative wound infection. Results of our findings suggest that while bacterial and air particulate is reduced by laminar air flow systems, there is no conclusive effect on the reduction of post-operative wound infections following total joint arthroplasty. We conclude that a combination of strict aseptic technique, prophylactic antibiotics and good anaesthetic control during surgery remains crucial to reduce post-operative surgical infections.
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Affiliation(s)
- M James
- Cardiff & Vale Orthopaedic Centre, Llandough University Hospital, Cardiff & Vale NHS Trust, Cardiff, UK
| | - W S Khan
- Cardiff & Vale Orthopaedic Centre, Llandough University Hospital, Cardiff & Vale NHS Trust, Cardiff, UK
| | - M R Nannaparaju
- Cardiff & Vale Orthopaedic Centre, Llandough University Hospital, Cardiff & Vale NHS Trust, Cardiff, UK
| | - J S Bhamra
- Cardiff & Vale Orthopaedic Centre, Llandough University Hospital, Cardiff & Vale NHS Trust, Cardiff, UK
| | - R Morgan-Jones
- Cardiff & Vale Orthopaedic Centre, Llandough University Hospital, Cardiff & Vale NHS Trust, Cardiff, UK
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13
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Putnis SE, Wartemberg GK, Khan WS, Agarwal S. A Literature Review of Total Hip Arthroplasty in Patients with Ankylosing Spondylitis: Perioperative Considerations and Outcome. Open Orthop J 2015; 9:483-8. [PMID: 26587066 PMCID: PMC4645831 DOI: 10.2174/1874325001509010483] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 04/14/2015] [Accepted: 05/22/2015] [Indexed: 12/17/2022] Open
Abstract
Ankylosing spondylitis is a spondyloarthropathy affecting the sacro-iliac joints with subsequent progression to the spine and the hip joints. The hip joints are affected by synovitis, enthesial inflammation, involvement of medullary bone, progressive degeneration and secondary osteoarthritis. Clinical presentation is usually in the form of pain and stiffness progressing to disabling fixed flexion contractures and in some instances, complete ankylosis. Hip arthroplasty should be considered for hip pain, postural and functional disability, or pain in adjacent joints due to hip stiffness. We conducted a literature review to determine peri-operative considerations and outcome in ankylosing spondylitis patients undergoing hip arthroplasty. In this review, we have discussed pre-operative surgical planning, thromboprophylaxis, anaesthetic considerations and heterotopic ossification. Outcomes of arthroplasty include range of movement, pain relief, survivorship and complications.
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Affiliation(s)
- S E Putnis
- Joint Reconstruction Unit, Royal National Orthopaedic Hospital, Stanmore, Middlesex, HA7 4LP, UK
| | - G K Wartemberg
- Joint Reconstruction Unit, Royal National Orthopaedic Hospital, Stanmore, Middlesex, HA7 4LP, UK
| | - W S Khan
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, Middlesex, HA7 4LP, UK
| | - S Agarwal
- Cardiff & Vale Orthopaedic Centre, Llandough University Hospital, Cardiff & Vale NHS Trust, Cardiff, CF5 2LD, UK
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14
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Nash WJ, Al-Nammari S, Khan WS, Pengas IP. Surgical management of the forefoot in patients with rheumatoid arthritis - a review article. Open Orthop J 2015; 9:78-83. [PMID: 25861409 PMCID: PMC4384227 DOI: 10.2174/1874325001509010078] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 01/25/2015] [Accepted: 02/03/2015] [Indexed: 11/22/2022] Open
Abstract
Foot and ankle pathologies cause a significant disease burden on rheumatoid patients. Forefoot pathologies causes pain, callosities and possibly ulceration, and can cause problems with footwear. Forefoot correction in rheumatoid patients has historically comprised of excision of diseased joints. While satisfaction was high with this procedure, complications, changing expectations and improvement in medical therapy have raised expectation of patients, physicians and surgeons alike. This review assesses the role of joint preserving osteotomies and arthrodesis, as well as associated complications. It also describes the role of the multidisciplinary team in the management of these patients.
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Affiliation(s)
- W J Nash
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, London, HA7 4LP, UK
| | - S Al-Nammari
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, London, HA7 4LP, UK
| | - W S Khan
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, London, HA7 4LP, UK
| | - I P Pengas
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, London, HA7 4LP, UK
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Abstract
Pre-existing cardiac disease contributes significantly to morbidity and mortality amongst patients undergoing non cardiac surgery. Patients with pre-existing cardiac disease or with risk factors for it, have as much as a 3.9% risk of suffering a major perioperative cardiac event (Lee et al 1999, Devereaux 2005). Furthermore, the incidence of perioperative myocardial infarction (MI) is increased 10 to 50 fold in patients with previous coronary events (Jassal 2008).
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Affiliation(s)
- N A Aresti
- Trauma & Orthopaedics, Royal London Hospital, Percivall Pott Rotation, Whitechapel Road, London E1 1BB.
| | - A A Malik
- SpR Trauma & Orthopaedic Surgery, Royal National Orthopaedic Hospital, Stanmore
| | | | - S M E Aftab
- SpR Spinal Surgery, Royal National Orthopaedic Hospital, Stanmore
| | - W S Khan
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore
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Asmatulu R, Muppalla H, Veisi Z, Khan WS, Asaduzzaman A, Nuraje N. Study of hydrophilic electrospun nanofiber membranes for filtration of micro and nanosize suspended particles. Membranes (Basel) 2013; 3:375-88. [PMID: 24957063 PMCID: PMC4021957 DOI: 10.3390/membranes3040375] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 10/18/2013] [Accepted: 10/21/2013] [Indexed: 11/24/2022]
Abstract
Polymeric nanofiber membranes of polyvinyl chloride (PVC) blended with polyvinylpyrrolidone (PVP) were fabricated using an electrospinning process at different conditions and used for the filtration of three different liquid suspensions to determine the efficiency of the filter membranes. The three liquid suspensions included lake water, abrasive particles from a water jet cutter, and suspended magnetite nanoparticles. The major goal of this research work was to create highly hydrophilic nanofiber membranes and utilize them to filter the suspended liquids at an optimal level of purification (i.e., drinkable level). In order to overcome the fouling/biofouling/blocking problems of the membrane, a coagulation process, which enhances the membrane’s efficiency for removing colloidal particles, was used as a pre-treatment process. Two chemical agents, Tanfloc (organic) and Alum (inorganic), were chosen for the flocculation/coagulation process. The removal efficiency of the suspended particles in the liquids was measured in terms of turbidity, pH, and total dissolved solids (TDS). It was observed that the coagulation/filtration experiments were more efficient at removing turbidity, compared to the direct filtration process performed without any coagulation and filter media.
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Affiliation(s)
- Ramazan Asmatulu
- Department of Mechanical Engineering, Wichita State University, 1845 Fairmount, Wichita, KS 67260, USA.
| | - Harish Muppalla
- Department of Electrical Engineering and Computer Science, Wichita State University, 1845 Fairmount, Wichita, KS 67260, USA.
| | - Zeinab Veisi
- Department of Mechanical Engineering, Wichita State University, 1845 Fairmount, Wichita, KS 67260, USA.
| | - Waseem S Khan
- Department of Mechanical Engineering, Wichita State University, 1845 Fairmount, Wichita, KS 67260, USA.
| | - Abu Asaduzzaman
- Department of Electrical Engineering and Computer Science, Wichita State University, 1845 Fairmount, Wichita, KS 67260, USA.
| | - Nurxat Nuraje
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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Khan WS, Malik A. Recent Advances and Developments in the Management of Soft Tissue Injuries. Open Orthop J 2012; 6:503-5. [PMID: 23248719 PMCID: PMC3522507 DOI: 10.2174/1874325001206010503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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18
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Bhamra JS, Khan WS, Pastides P. The use of the s-quattro dynamic external fixator for the treatment of intra-articular phalangeal fractures: a review of the literature. Open Orthop J 2012; 6:54-9. [PMID: 22431950 PMCID: PMC3293159 DOI: 10.2174/1874325001206010054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 09/14/2011] [Accepted: 09/17/2011] [Indexed: 11/22/2022] Open
Abstract
Intra-articular phalangeal fractures are a common injury. If left untreated, these injuries can lead to poor functional outcome with severe dehabilitating consequences, especially in younger patients. The S-Quattro external fixator device (Surgicraft®, UK) can be used to treat such injuries. Its use has been widely documented and has shown many advantages in comparison to other conventional treatments. Advantages include reduced operative time, rigid fixation and early range of motion. We present a review of the current literature and use of the S-Quattro serpentine system in the management of intraarticular phalangeal fractures.
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Affiliation(s)
- J S Bhamra
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, Middlesex, HA7 4LP, UK
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Affiliation(s)
- W S Khan
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, Middlesex, HA7 4LP, UK
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Abstract
Carpal Tunnel Syndrome (CTS) remains a puzzling and disabling condition present in 3.8% of the general population. CTS is the most well-known and frequent form of median nerve entrapment, and accounts for 90% of all entrapment neuropathies. This review aims to provide an overview of this common condition, with an emphasis on the pathophysiology involved in CTS. The clinical presentation and risk factors associated with CTS are discussed in this paper. Also, the various methods of diagnosis are explored; including nerve conduction studies, ultrasound, and magnetic resonance imaging.
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Affiliation(s)
- I Ibrahim
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore, HA7 4LP, UK
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21
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Khan WS, Adesida AB, Tew SR, Longo UG, Hardingham TE. Fat pad-derived mesenchymal stem cells as a potential source for cell-based adipose tissue repair strategies. Cell Prolif 2012; 45:111-20. [PMID: 22260253 DOI: 10.1111/j.1365-2184.2011.00804.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Mesenchymal stem cells are able to undergo adipogenic differentiation and present a possible alternative cell source for regeneration and replacement of adipose tissue. The human infrapatellar fat pad is a promising source of mesenchymal stem cells with many source advantages over from bone marrow. It is important to determine whether a potential mesenchymal stem-cell exhibits tri-lineage differentiation potential and is able to maintain its proliferation potential and cell-surface characterization on expansion in tissue culture. We have previously shown that mesenchymal stem cells derived from the fat pad can undergo chondrogenic and osteogenic differentiation, and we characterized these cells at early passage. In the study described here, proliferation potential and characterization of fat pad-derived mesenchymal stem cells were assessed at higher passages, and cells were allowed to undergo adipogenic differentiation. MATERIALS AND METHODS Infrapatellar fat pad tissue was obtained from six patients undergoing total knee replacement. Cells isolated were expanded to passage 18 and proliferation rates were measured. Passage 10 and 18 cells were characterized for cell-surface epitopes using a range of markers. Passage 2 cells were allowed to undergo differentiation in adipogenic medium. RESULTS The cells maintained their population doubling rates up to passage 18. Cells at passage 10 and passage 18 had cell-surface epitope expression similar to other mesenchymal stem cells previously described. By staining it was revealed that they highly expressed CD13, CD29, CD44, CD90 and CD105, and did not express CD34 or CD56, they were also negative for LNGFR and STRO1. 3G5 positive cells were noted in cells from both passages. These fat pad-derived cells had adipogenic differentiation when assessed using gene expression for peroxisome proliferator-activated receptor γ2 and lipoprotein lipase, and oil red O staining. DISCUSSION These results indicate that the cells maintained their proliferation rate, and continued expressing mesenchymal stem-cell markers and pericyte marker 3G5 at late passages. These results also show that the cells were capable of adipogenic differentiation and thus could be a promising source for regeneration and replacement of adipose tissue in reconstructive surgery.
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Affiliation(s)
- W S Khan
- United Kingdom Centre for Tissue Engineering, University of Manchester, Manchester, UK
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22
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Mafi R, Hindocha S, Mafi P, Griffin M, Khan WS. Sources of adult mesenchymal stem cells applicable for musculoskeletal applications - a systematic review of the literature. Open Orthop J 2011; 5 Suppl 2:242-8. [PMID: 21886689 PMCID: PMC3149887 DOI: 10.2174/1874325001105010242] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Revised: 03/24/2011] [Accepted: 04/21/2011] [Indexed: 12/11/2022] Open
Abstract
Mesenchymal stem cells (MSCs) were first discovered by Friedenstein and his colleagues in 1976 from bone marrow. The unique property of these cells was their potential to develop into fibroblastic colony forming cells. Since Friedenstein’s discovery of these cells the interest in adult MSCs has been progressively growing. Nowadays MSCs are defined as undeveloped biological cells capable of proliferation, self renewal and regenerating tissues. All these properties of MSCs have been discovered in the past 35 years. MSCs can play a crucial role in tissue engineering, organogenesis, gene therapy, transplants as well as tissue injuries. These cells were mainly extracted from bone marrow but there have been additional sources for MSCs discovered in the laboratories including: muscle, dermis, trabecular bone, adipose tissue, periosteum, pericyte, blood, synovial membrane and so forth. The discovery of the alternative sources of MSCs helps widen the application of these cells in different areas of medicine. By way of illustration, they can be used in various therapeutic purposes such as tissue regeneration and repair in musculoskeletal diseases including osteonecrosis of femoral head, stimulating growth in children with osteogenesis imperfecta, disc regeneration, osteoarthritis and duchenne muscular dystrophy. In order to fully comprehend the characteristics and potential of MSCs future studies in this field are essential.
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Affiliation(s)
- R Mafi
- The Hull York Medical School, Hertford Building, Hull, HU6 7RX, UK
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23
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Abstract
Ilizarov frames provide a versatile fixation system for the management of bony deformities, fractures and their complications. The frames give stability, soft tissue preservation, adjustability and functionality allowing bone to realise its full osteogenic potential. It is important that we have a clear and concise understanding of the Ilizarov principles of deformity correction to best make use of this fixation system. In this review article, the history of Ilizarov frame, the basic sciences behind it, the mechanical principles governing its use and the clinical use of the fixation system are discussed.
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Affiliation(s)
- B Spiegelberg
- University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, Middlesex, UK
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Khan WS, Adesida AB, Tew SR, Andrew JG, Hardingham TE. The epitope characterisation and the osteogenic differentiation potential of human fat pad-derived stem cells is maintained with ageing in later life. Injury 2009; 40:150-7. [PMID: 19070850 DOI: 10.1016/j.injury.2008.05.029] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2008] [Revised: 05/15/2008] [Accepted: 05/16/2008] [Indexed: 02/02/2023]
Abstract
Some clinical settings are deficient in osteogenic progenitors, e.g. atrophic nonunited fractures, large bone defects, and regions of scarring and osteonecrosis. These benefit from the additional use of bone marrow-derived mesenchymal stem cells, but these cells exhibit an age-related decline in lifespan, proliferation and osteogenic potential. Therapeutic approaches for the repair of bone could be optimised by the identification of a stem cell source that does not show age-related changes. Fat pad-derived stem cells are capable of osteogenesis, but a detailed study of the effect of ageing on their epitope profile and osteogenic potential has so far not been performed. Fat pad-derived cells were isolated from 2 groups of 5 patients with a mean age of 57 years (S.D. 3 years) and 86 years (S.D. 3 years). The proliferation, epitope profile and osteogenic differentiation potential of cells from the 2 groups were compared. Cells isolated from the fat pad of both groups showed similar proliferation rates and exhibited a cell surface epitope profile similar but not identical to that of bone marrow-derived stem cells. The cells from both groups cultured in osteogenic medium exhibited osteogenesis as shown by a significant upregulation of alkaline phosphatase and osteocalcin genes, and significantly greater alkaline phosphatase enzyme activity compared to cells cultured in the control medium. The cells cultured in the osteogenic medium also showed greater calcium phosphate deposition on alizarin red staining. There was no significant difference between the osteogenic potential of the two age groups for any of the parameters studied. The fat pad is a consistent and homogenous source of stem cells that exhibits osteogenic differentiation potential with no evidence of any decline with ageing in later life. This has many potential therapeutic tissue engineering applications for the repair of bone defects in an increasingly ageing population.
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Affiliation(s)
- W S Khan
- United Kingdom Centre for Tissue Engineering and Wellcome Trust Centre for Cell Matrix Research, University of Manchester, Oxford Road, Manchester M13 9PT, UK.
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Khan WS, Agarwal M, Malik AA, Cox AG, Denton J, Holt EM. Chromium, cobalt and titanium metallosis involving a Nottingham shoulder replacement. ACTA ACUST UNITED AC 2008; 90:502-5. [PMID: 18378928 DOI: 10.1302/0301-620x.90b4.20302] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Metallosis after shoulder replacement has not previously been described in the literature. We report a patient who developed extensive metallosis after implantation of an uncemented Nottingham shoulder replacement. He underwent a revision procedure. Examination of the retrieved prosthesis showed that the titanium porous coating was separating from the humeral stem and becoming embedded in the ultra-high-molecular-weight polyethylene glenoid component, resulting in abrasive wear of the humeral component. There was metallosis despite exchange of the modular humeral head. Both components had to be exchanged to resolve the problem.
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Affiliation(s)
- W S Khan
- Musculoskeletal Research Group, University of Manchester, Oxford Road, Manchester M13 9PT, UK.
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Khan WS, Jones RK, Nokes L, Johnson DS. How accurate are lockable orthotic knee braces? An objective gait analysis study. Knee 2007; 14:497-9. [PMID: 17766123 DOI: 10.1016/j.knee.2007.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2007] [Revised: 07/23/2007] [Accepted: 08/02/2007] [Indexed: 02/02/2023]
Abstract
There has been an increasing use of orthotic knee braces in the management of knee injuries but, to our knowledge, there is no gait analysis study assessing the accuracy of these braces. Eight healthy male subjects were studied to determine the accuracy of immobilisation or splintage provided by a lockable orthotic knee brace using gait analysis. Six types of immobilisation were studied: locked at 0, 10, 20, 30 degrees and unlocked in an orthotic knee brace, and without a brace. The knee flexion angles measured using the kinematic instruments at 0 and 10 degrees were significantly greater than those set at the knee brace. The knee flexion angle measured using the unlocked knee brace was significantly greater than that measured in the absence of a brace. This study highlights inaccuracies in a knee brace at low knee flexion angles. The higher actual angles alter the biomechanics of the knee joint and result in greater forces across the knee joint and especially the extensor mechanism.
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Affiliation(s)
- W S Khan
- Department of Trauma and Orthopaedics, Stockport NHS Foundation Trust, Stepping Hill Hospital, Stockport, UK.
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Khan WS, Jones RK, Nokes L, Johnson DS. The relationship of the angle of immobilisation of the knee to the force applied to the extensor mechanism when partially weight-bearing. ACTA ACUST UNITED AC 2007; 89:911-4. [PMID: 17673584 DOI: 10.1302/0301-620x.89b7.18452] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We describe the influence of the angle of immobilisation during partial weight-bearing on the forces across the extensor mechanism of the knee. Gait analysis was performed on eight healthy male subjects with the right knee in an orthotic brace locked at 0°, 10°, 20° and 30°, with the brace unlocked and also without a brace. The ground reaction force, the angle of the knee and the net external flexion movement about the knee were measured and the extensor mechanism force was calculated. The results showed a direct non-linear relationship between the angle of knee flexion and the extensor mechanism force. When a brace was applied, the lowest forces occurred when the brace was locked at 0°. At 30° the forces approached the failure strength of some fixation devices. We recommend that for potentially unstable injuries of the extensor mechanism, when mobilising with partial weight-bearing, the knee should be flexed at no more than 10°.
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Affiliation(s)
- W S Khan
- Department of Trauma and Orthopaedics, Stockport NHS Foundation Trust, Stockport SK2 7JE, UK.
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28
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Abstract
Neglected fracture dislocations of ankle are rare in western countries. Failure to achieve anatomic reduction is associated with a poor prognosis. We present a case of a patient with a neglected Weber B fracture of the fibula with postero-lateral subluxation of the ankle. In theatre, the subluxation could not be reduced, and a posterior and lateral soft tissue release was performed. Granulation tissue was removed from the medial gutter. The fibular fracture was reduced and fixed with a six-hole dynamic compression plate. Post-operative radiographs was satisfactory and the patient was followed up for 12 months with full range of movement and function of the joint. In our case, correction was not obtained by osteotomy of the lateral malleolus alone, and medial and posterior soft tissue release was required. This was due to disruption of the deltoid ligament and posterior tibiofibular ligament and the associated scar tissue. Previous studies have shown that, if anatomic reduction is achieved, results with delayed surgery can be as good as those obtained with immediate surgery. Surgically correcting an old fracture dislocation is a difficult undertaking due to soft-tissue contractures and malunited fractures. It is important to preserve as much soft tissue attachments and periosteum to prevent avascular necrosis.
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Affiliation(s)
- W S Khan
- Department of orthopaedics & trauma, Stepping hill hospital, Stockport, UK
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