184 results on '"Learmonth ID"'
Search Results
2. Validation for the Reduced Western Ontario and McMaster Universities Osteoarthritis Index Function Scale
- Author
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Whitehouse, SL, primary, Crawford, RW, additional, and Learmonth, ID, additional
- Published
- 2008
- Full Text
- View/download PDF
3. Femoral Cementing Techniques: Current Trends in the UK
- Author
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Nedungayil, SK, primary, Mehendele, S, additional, Gheduzzi, S, additional, and Learmonth, ID, additional
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- 2006
- Full Text
- View/download PDF
4. Fracture and loosening of Charnley femoral stems. Comparison between first-generation and subsequent designs
- Author
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Dall, DM, primary, Learmonth, ID, additional, Solomon, MI, additional, Miles, AW, additional, and Davenport, JM, additional
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- 1993
- Full Text
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5. Test-retest reliability of Quantitative Sensory Testing in knee osteoarthritis and healthy participants.
- Author
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Wylde V, Palmer S, Learmonth ID, Dieppe P, Wylde, V, Palmer, S, Learmonth, I D, and Dieppe, P
- Abstract
Quantitative Sensory Testing (QST), which assesses somatosensory function by recording participant's responses to external stimuli of controlled intensity, is a useful tool to provide insight into the complex pathophysiology of osteoarthritis (OA) pain. However, QST is not commonly used in rheumatology because the test-retest reliability properties of QST in OA patients have not yet been established. This brief report presents the finding of a study which assessed the test-retest reliability of light touch thresholds, pressure pain thresholds, thermal sensation thresholds and thermal pain thresholds in 50 knee OA patients and 50 healthy participants. Pressure pain thresholds were found to be the least variable measurement, as median thresholds did not differ significantly over the 1 week period and the results were highly correlated. This provides support for the inclusion of pressure algometry in studies assessing pain perception abnormalities in OA. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
6. Bilateral avascular necrosis of the talus following strenuous physical activity
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Travlos, J, primary and Learmonth, ID, additional
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- 1991
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7. Skin closure after total hip replacement: a randomised controlled trial of skin adhesive versus surgical staples.
- Author
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Livesey C, Wylde V, Descamps S, Estela CM, Bannister GC, Learmonth ID, and Blom AW
- Published
- 2009
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8. Periprosthetic DXA after total hip arthroplasty with short vs. ultra-short custom-made femoral stems: 37 patients followed for 3 years.
- Author
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Albanese CV, Santori FS, Pavan L, Learmonth ID, and Passariello R
- Abstract
Background and purpose Dual-energy X-ray absorptiometry (DXA) analysis of the 7 periprosthetic Gruen zones is the most commonly used protocol to evaluate bone remodeling after the implantation of conventional femoral stems. We assessed the value of DXA after cementless primary total hip arthroplasty (THA) by comparing the effect of progressive shortening of the stem of two femoral implants on periprosthetic bone remodeling using a specifically developed protocol of analysis with 5 periprosthetic regions of interest (ROIs). Patients and methods Bone mineral density (BMD) was evaluated in 37 patients in the plateau stage, 3 years after THA. Two femoral implants featuring conceptually new designs and surgical technique were tested: types 1 and 2, characterized by extremely short stem and virtual absence of distal stem, respectively. Results We found that progressive shortening of the femoral stem produces more proximal loading, which effectively preserves metaphyseal bone stock and increases periprosthetic BMD in the medial ROIs over time. In the type 2 group, higher absolute BMD values were observed in medial ROIs 4 and 5. No differences were found in ROIs 1, 2, and 3. Interpretation This study shows the flexibility of DXA in adapting the protocol of periprosthetic analysis to the specific requirements of new implant designs, and it shows its high sensitivity in evaluation of the biological response of bone to changes in implant shape. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
9. Impaction bone grafting of the acetabulum at hip revision using a mix of bone chips and a biphasic porous ceramic bone graft substitute: good outcome in 43 patients followed for a mean of 2 years.
- Author
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Blom AW, Wylde V, Livesey C, Whitehouse MR, Eastaugh-Waring S, Bannister GC, and Learmonth ID
- Abstract
BACKGROUND AND PURPOSE: One of the greatest problems of revision hip arthroplasty is dealing with lost bone stock. Good results have been obtained with impaction grafting of allograft bone. However, there have been problems of infection, reproducibility, antigenicity, stability, availability of bone, and cost. Thus, alternatives to allograft have been sought. BoneSave is a biphasic porous ceramic specifically designed for use in impaction grafting. BoneSave is 80% tricalcium phosphate and 20% hydroxyapatite. Previous in vitro and in vivo studies have yielded good results using mixtures of allograft and BoneSave, when compared with allograft alone. This study is the first reported human clinical trial of BoneSave in impaction grafting. METHODS: We performed a single-institution, multi-surgeon, prospective cohort study. 43 consecutive patients underwent revision hip arthroplasty using BoneSave and allograft to restore missing bone in the acetabulum. 9 patients had cemented acetabular components implanted and 34 uncemented. 10 patients had cemented femoral components implanted and 1 had an uncemented femoral component. 32 patients did not have their femoral component revised. RESULTS: No patients were lost to follow-up. At a mean follow-up of 24 (11-48) months, there were no re-revisions and there was no implant migration. 1 acetabular component had confluent lucent lines at the implant-graft interface. Complications were rare (1 fracture, 2 dislocations). Patient satisfaction with the procedure was high. INTERPRETATION: Short-term results indicate that impaction grafting of BoneSave and allograft is an effective method of dealing with loss of bone stock at revision hip surgery. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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- View/download PDF
10. Subsidence of the stem after impaction bone grafting for revision hip replacement using irradiated bone.
- Author
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Hassaballa M, Mehendale S, Poniatowski S, Kalantzis G, Smith E, and Learmonth ID
- Published
- 2009
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11. The effect of selected muscle groups on knee pressure distribution
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Schmotzer, H, primary, Learmonth, ID, additional, and Vaughan, CL, additional
- Published
- 1991
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12. Direct measurements of tibio-femoral contact pressures for various deformities of the knee
- Author
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Schmotzer, H, primary, Vaughan, CL, additional, and Learmonth, ID, additional
- Published
- 1991
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13. The Harris-Galante porous-coated, hemispherical, polyethylene-lined acetabular component in patients under 50 years of age: a 12- to 16-year review.
- Author
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Utting MR, Raghuvanshi M, Amirfeyz R, Blom AW, Learmonth ID, and Bannister GC
- Published
- 2008
- Full Text
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14. Ten-year results of a bone-preserving low-modulus composite total hip replacement stem.
- Author
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White SP, Lee MB, Galpin J, and Learmonth ID
- Abstract
A cementless composite femoral stem was developed with the aim of reducing bone loss secondary to stress shielding. Thirty-one stems were implanted in 27 patients, combined with a cementless acetabular component with polyethylene bearing surface in 30 cases and a bipolar head in 1 case. Patients were followed-up annually with clinical and radiographic evaluation. Fourteen hips underwent dual X-ray absorptiometry (DEXA) scans to monitor postoperative bone mineral density around the stem. The mean follow-up was 10.1 years. The mean Harris hip score improved from 57 to 92. To date, no stem has required revision. All stems are radiographically stable. Acetabular component revision has been required in 8 cases; 3 for liner dissociation and 5 for polyethylene wear. Radiographs and DEXA scans have shown some improvement in bone mineral density (BMD) between the 2 and 5-year follow-up. A cohort of patients displayed improvement in radiographic appearance and BMD in Gruen zone 7. This stem shows evidence of proximal bone preservation and has excellent results at medium to long-term follow-up. The limiting factor in our cohort of patients has been the polyethylene bearing surface. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
15. Total hip replacement and the law of diminishing returns.
- Author
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Learmonth ID and Learmonth, Ian D
- Published
- 2006
16. Patient expectations regarding total knee arthroplasty: differences among the United States, United Kingdom, and Australia.
- Author
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Lingard EA, Sledge CB, Learmonth ID, Lingard, Elizabeth A, Sledge, Clement B, Learmonth, Ian D, and Kinemax Outcomes Group
- Abstract
Background: Total knee arthroplasty is an effective treatment for severe osteoarthritis of the knee. Our aim was to determine whether patients from the United Kingdom, United States, and Australia have different preoperative expectations regarding total knee arthroplasty and whether these expectations have an impact on outcomes and patient satisfaction.Methods: Patients from the United Kingdom, the United States, and Australia were recruited into a prospective observational study of primary total knee arthroplasty for the treatment of osteoarthritis. Preoperative expectations, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Short Form-36 (SF-36) scores, and demographic, socioeconomic, and follow-up data, including satisfaction with outcome, were obtained from self-administered patient questionnaires.Results: A total of 598 patients with a mean age of sixty-nine years at the time of the index arthroplasty were recruited; 58% were women. The majority of patients expected to have no pain at twelve months after the surgery, and with the numbers available there was no significant difference among the countries with regard to pain expectations. Australian patients were more likely than patients in the United Kingdom or the United States to expect better function at twelve months after the surgery. With the numbers available, satisfaction scores at twelve months did not differ significantly among the countries and were not influenced by preoperative expectations. Australian patients were more likely than patients in the United Kingdom or the United States to be unwilling to undergo total knee arthroplasty again at twelve months under similar circumstances.Conclusions: Patients from different countries have different expectations regarding total knee arthroplasty, which are not fully explained by differences in sociodemographic factors, clinical characteristics, and pain and functional status. Australian patients had the highest expectations but, despite reporting similar outcomes and satisfaction following total knee arthroplasty, they were more likely not to want to have the surgery again under similar circumstances. [ABSTRACT FROM AUTHOR]- Published
- 2006
17. Post-traumatic lateral instability of the cervical spine
- Author
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Grobler, G, primary and Learmonth, ID, additional
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- 1990
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18. Core decompression for early atraumatic osteonecrosis of the femoral head
- Author
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Learmonth, ID, primary, Maloon, S, additional, and Dall, G, additional
- Published
- 1990
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19. (ii) Conservative hip implants.
- Author
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Learmonth ID
- Abstract
Arthritis of the hip primarily involves the articulation between the femoral head and the acetabulum. The primary surgical objective is to replace these articular surfaces. In achieving this it is desirable to attempt to obtain a homogeneous transfer of forces to the proximal femur. This is best provided by retention of the femoral neck.Survivorship of the implant is determined by the durability of fixation and of the articular interface. Early attempts to achieve a conservative hip replacement were betrayed by poor materials, inadequate fixation and failure of the articulation. This paper explores how these shortcomings were addressed during the evolution of total hip arthroplasty to produce the contemporary designs of conservative hip implants. [ABSTRACT FROM AUTHOR]
- Published
- 2005
20. Artificial joints: a biotechnological revolution.
- Author
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Learmonth ID and Learmonth, I D
- Published
- 2005
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21. A simple technique for varus supracondylar osteotomy in genu valgum
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Learmonth, ID, primary
- Published
- 1990
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22. Radiographic associations for 'primary' hip osteoarthrosis: a retrospective cohort study of 47 patients.
- Author
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Vossinakis IC, Karnezis IA, Parry K, and Learmonth ID
- Abstract
This radiographic retrospective cohort study aims to identify relations between the prearthrotic anatomy of the hip joint and the type of subsequent osteoarthrosis (OA). Radiographs of 64 hips in 47 patients were evaluated. Several anatomical indices were measured on radiographs obtained before the onset of OA. The location, type and grade of OA were recorded on subsequent radiographs. Due to the small number of hips available, only three potential risk factors could be considered for both OA location and OA type (weight-bearing surface angle, spherical sector and neck shaft angle for both outcomes). The only variable that was found to be a significant predictor of OA location was the degree of inclination of the acetabular sourcil. Patients with craniomedial sourcils were more likely to have medial OA. No predictors of OA type could be identified. Our results suggest that the anatomy of the hip joint is a factor determining the location of developing osteoarthrosis. [ABSTRACT FROM AUTHOR]
- Published
- 2001
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23. Internal fixation for occipito-cervical fusion
- Author
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Heywood, AW, Learmonth, ID, and Thomas, M
- Abstract
We describe a method of internal fixation for occipito-cervical fusion utilising a standard "small fragment" T-plate bent and fixed to the skull with three screws. The lower end of the plate is screwed and wired firmly to the spine of the axis. Of 14 patients so treated, 12 fused, one died and one failed to unite to the skull. Of eight with cord signs, seven remitted or improved and one died.
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- 1988
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24. Cervical spine instability in rheumatoid arthritis
- Author
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Heywood, AW, Learmonth, ID, and Thomas, M
- Abstract
We present a study of 30 fusion operations in 26 rheumatoid arthritics with cervical spine instability. Atlanto-axial instability was present in 15, of whom 12 were fused; three had cord involvement and all made a partial or complete recovery following fusion. Cranial settling necessitated cranio-cervical fusion in four patients; all fused, and one with myelopathy was relieved. Subaxial instability required fusion in seven cases; two postoperative deaths followed the only two anterior interbody fusions. Posterior fusion was successful in the other five, with remission of neurological compromise in the three with myelopathy and one with radiculopathy. We conclude that neurological compromise in an unstable but mobile rheumatoid cervical spine can usually be brought to remission by immobilisation alone, so decompressive procedures are unnecessary in the first instance.
- Published
- 1988
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25. Radiological loosening after cemented hip replacement for juvenile chronic arthritis
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Learmonth, ID, Heywood, AW, Kaye, J, and Dall, D
- Abstract
We reviewed the results of 14 total hip replacements in patients with juvenile chronic arthritis. The mean age at operation was 16 years (range 12 to 22 years); follow-up was from four to 11 years (mean 8.5 years). Postoperatively pain relief was sustained in all but one hip, while movement generally remained significantly restricted. No hip has as yet required a revision operation, although eight hips (57%) show radiological changes suggestive of impending failure. All patients had severe polyarticular involvement with associated restriction of locomotor activity. Potential causes contributing to loosening such as continuing diaphyseal bone growth and increased immunocompetence in adolescence are discussed.
- Published
- 1989
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26. Namaqualand Hip Dysplasia Orthopedic Implications
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Peter Beighton, Christy G, and Learmonth Id
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Adult ,Pediatrics ,medicine.medical_specialty ,Adolescent ,Gradual progression ,South Africa ,Skeletal disorder ,Terminology as Topic ,medicine ,Humans ,Orthopedics and Sports Medicine ,Hip pain ,Child ,Hip Dislocation, Congenital ,business.industry ,Effective management ,Degenerative arthropathy ,General Medicine ,Namaqualand hip dysplasia ,Surgery ,Radiography ,Child, Preschool ,Orthopedic surgery ,Hip Joint ,Hip Prosthesis ,business ,Total hip arthroplasty - Abstract
Namaqualand hip dysplasia (NHD) is an inherited skeletal disorder that has been identified in 45 persons in five generations of a large family in South Africa. Involvement of the femoral capital epiphyses, which was present in all cases, led to significant orthopedic complications. Hip pain developed between three and 20 years of age and heralded the onset and gradual progression of premature degenerative arthropathy. The patients who were examined were all over 35 years of age; four had been treated by total hip arthroplasty. For appropriate and effective management of this uncommon but well-defined syndromic entity, an early and specific diagnosis is essential.
- Published
- 1987
27. Comparisons between asymptomatic participants defined by a criterion categorization system in patients with patellofemoral joint pain using plantar pressure measurement: part B.
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Curran SA, Mathieson I, Upton D, and Learmonth ID
- Published
- 2010
28. A cross-sectional survey to formulate clinical patellofemoral joint alignment and foot posture categories: part A.
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Curran SA, Upton D, Mathieson I, and Learmonth ID
- Published
- 2010
29. Outcome assessment following total hip replacement.
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Learmonth ID, Cavendish VJ, Learmonth, I D, and Cavendish, V J
- Abstract
Outcome assessment after hip anthroplasty is relevant both to in-depth research of specific procedures and to monitoring standards of practice. Instruments of outcome assessment should be fast, easy to use, reliable, specific to the question being asked, cost-effective, and applicable. Increasing evidence exists that patient-based outcome measures are more reliable than those based on clinicians' scores. This article reviews the types of instruments that are available and offers guidance about the outcome measures that are most approprate for orthopedic surgeons. [ABSTRACT FROM AUTHOR]
- Published
- 2005
30. Re: Biocompatibility: a biomechanical and biological concept in total hip replacement. Surg. J R Coll Surg Edinb Irel. 2003; 1:1-8.
- Author
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Spedding RL, Spedding PL, and Learmonth ID
- Published
- 2004
31. The usage of image trigonometry in bone measurements.
- Author
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Dymond IW, Ashforth JA, Dymond GF, Spirakis T, and Learmonth ID
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- Humans, Reproducibility of Results, Algorithms, Femur diagnostic imaging, Imaging, Three-Dimensional, Tomography, X-Ray Computed methods
- Abstract
The entire musculo-skeletal system responds dynamically to stresses and strains applied to it. Restoring normal biomechanics contributes to the normal function that ensures that physiological stresses and strains are preserved. Appropriate preoperative planning is mandatory to restore normal biomechanics at reconstructive surgery. Effective preoperative planning depends on the ability to reproducibly make accurate measurements of lengths and angles from plain radiographs. Measurement has become an integral part of orthopaedics to define morphological abnormality, to plan for reconstruction and for comparative research. The most prevalent method of measurement is usually based on lines drawn on radiographs with no accurate reference to the actual geometry of the structures. This two-dimensional projection of an asymmetrical three-dimensional structure leads to inaccuracy and consequently to a compromise in the overall precision of many procedures. In addition it is also difficult to monitor the progression of disease as the exact relationship of the bones and joints to each other, and to prosthetics, cannot be accurately recorded. This paper presents a method of digitally measuring relevant bone parameters in a geometric manner in order to achieve accurate, repeatable measurements.
- Published
- 2013
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32. Blood levels of cobalt and chromium are inversely correlated to head size after metal-on-metal resurfacing arthroplasty.
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Parry MC, Eastaugh-Waring S, Bannister GC, Learmonth ID, Case CP, and Blom AW
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- Adult, Chromium Alloys chemistry, Female, Follow-Up Studies, Humans, Male, Middle Aged, Prosthesis Design, Prosthesis Failure, Reoperation, Retrospective Studies, Time Factors, Young Adult, Arthroplasty, Replacement, Hip, Chromium blood, Chromium Alloys pharmacokinetics, Cobalt blood, Hip Prosthesis, Pain, Postoperative blood
- Abstract
Resurfacing arthroplasty has fallen out of favour in recent years due to unfavourable survivorship in joint registries and alarming reports of soft tissue reactions around metal on metal prostheses. Our aim was to assess the effect of head size, implant design and component positioning on metal production by resurfacing arthroplasties. We measured whole blood cobalt and chromium and component position in matched populations implanted with two designs of resurfacing arthroplasty over a two-year period. Both implants resulted in a significant increase in blood metal levels (p<0.001) though the ASR design generated significantly higher metal levels (p = 0.041). A significant inverse correlation was seen between component size and blood cobalt levels (p = 0.032) and blood chromium levels (p<0.001). No correlation was identified between component position and blood metal levels. Small diameter metal resurfacing components result in increased metal generation compared with larger components. As increased metal generation has been correlated to wear and therefore failure, caution must be used on implantation of smaller components and indeed, in those who require smaller components, alternative bearing materials should be considered. These results contrast with recent findings which have demonstrated early failure for larger diameter stemmed metal-on-metal prostheses.
- Published
- 2013
- Full Text
- View/download PDF
33. The association between pre-operative pain sensitisation and chronic pain after knee replacement: an exploratory study.
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Wylde V, Palmer S, Learmonth ID, and Dieppe P
- Subjects
- Aged, Arthralgia diagnosis, Arthralgia etiology, Chronic Pain diagnosis, Female, Follow-Up Studies, Hot Temperature adverse effects, Humans, Male, Middle Aged, Osteoarthritis, Knee complications, Osteoarthritis, Knee surgery, Pain Measurement, Pain, Postoperative diagnosis, Pain, Postoperative etiology, Predictive Value of Tests, Preoperative Care, Pressure adverse effects, Arthralgia physiopathology, Arthroplasty, Replacement, Knee adverse effects, Chronic Pain physiopathology, Osteoarthritis, Knee physiopathology, Pain Threshold physiology, Pain, Postoperative physiopathology
- Abstract
Objective: Chronic pain after total knee replacement (TKR) is a prevalent condition, affecting about 20% of patients. The aim of this study was to explore the relationship between pre-operative pain thresholds and chronic pain after TKR., Design: Patients listed for a TKR because of osteoarthritis participated in a Quantitative Sensory Testing (QST) session prior to surgery. Pressure pain thresholds (PPTs) and hot pain thresholds were assessed at the osteoarthritic knee and the forearm. Patients were followed-up at 1-year after TKR, and the severity of pain in the replaced knee was assessed using the WOMAC Pain score. Pre-operative median QST thresholds were compared to thresholds from a normative database collected from 50 people with no knee pain. The relationship between pre-operative pain thresholds and pain severity post TKR were tested using correlations., Results: Fifty-one patients participated in a pre-operative QST session and completed a 1-year WOMAC Pain score. Pre-operatively, patients demonstrated evidence of localised (knee) and widespread (forearm) pain sensitisation in response to pressure stimuli compared to healthy participants. Pre-operative PPTs at the forearm were found to be significantly correlated with 1-year WOMAC Pain scores (r = 0.37, P = 0.008)., Conclusions: This study provides preliminary evidence that pre-operative widespread pain sensitisation, measured using pressure algometry, may be associated with chronic pain after TKR. Further research is needed to explore the predictive value of an assessment of pre-operative widespread pain sensitisation in identifying who is likely to develop chronic pain after TKR., (Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
34. Surgeon records in the public domain.
- Author
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Spencer RF, Villar RN, Field RE, and Learmonth ID
- Subjects
- United Kingdom, Access to Information, Arthroplasty, Orthopedics, Records
- Published
- 2013
- Full Text
- View/download PDF
35. Primary and revision THA using a stemless metaphyseal-loading implant above distorted proximal femoral anatomy.
- Author
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Young PS, Middleton RG, Vasukutty NL, Uzoigwe CE, Learmonth ID, and Minhas TH
- Subjects
- Adult, Aged, Epiphyses, Slipped epidemiology, Femoral Fractures epidemiology, Humans, Male, Middle Aged, Osteoarthritis, Hip epidemiology, Osteoarthritis, Hip surgery, Prosthesis Design, Reoperation, Treatment Failure, Arthroplasty, Replacement, Hip, Hip Prosthesis
- Abstract
Total hip arthroplasty is well established as a successful treatment for end stage arthritis, with a wide variety of components currently available. Using traditional stemmed implants in patients with a distorted proximal femur can be technically challenging with an increased risk of complications. We present seven patients with distorted proximal femoral anatomy or failed hip arthroplasty in whom a short, metaphyseal loading implant was utilised. At minimum two-year follow-up there have been no complications with all stems stable and well fixed radiologically. Average improvement in Oxford Hip Score is 32. We suggest that a short, metaphyseal loading prosthesis can be considered in cases where a conventional stemmed implant may not be suitable due to challenging proximal femoral anatomy.
- Published
- 2013
- Full Text
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36. Hip International in 2012.
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Spencer RF, Toni A, and Learmonth ID
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- Humans, Periodicals as Topic, Arthroplasty, Editorial Policies, Hip Joint surgery, Orthopedics education, Orthopedics methods
- Published
- 2012
- Full Text
- View/download PDF
37. Medium-term outcome in patients treated with total hip arthroplasty using a modular femoral stem.
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Dagnino A, Grappiolo G, Benazzo FM, Learmonth ID, Spotorno L, and Portinaro N
- Subjects
- Activities of Daily Living, Adult, Aged, Aged, 80 and over, Arthroplasty, Replacement, Hip adverse effects, Cementation, Cohort Studies, Female, Health Status, Humans, Male, Metal-on-Metal Joint Prostheses, Middle Aged, Outcome Assessment, Health Care, Postoperative Complications, Quality of Life, Range of Motion, Articular, Recovery of Function, Treatment Outcome, Arthroplasty, Replacement, Hip instrumentation, Arthroplasty, Replacement, Hip methods, Femur surgery, Hip Prosthesis, Prosthesis Design, Prosthesis Failure
- Abstract
The clinical, radiographic and quality of life results of total hip arthroplasty using the MODULUS cementless modular femoral stem were reviewed. 48 patients who had a total hip arthroplasty using the MODULUS femoral stem were identified. Six had bilateral procedures, resulting in 60 hips with complete clinical and radiographic data. Mean age at implantation was 50 years (range 33 to 82). Mean follow-up was 59 months (range 50 months to 73). There were two early post-operative dislocations (within 2 days). One patient required further surgery to remove heterotopic bone. Mean Harris Hip Score increased from 37 points preoperatively (range, 7 to 66) to 89 points at final review (range, 65 to 100 points). Radiographic evaluation revealed that all implants were stable without evidence of osteolysis but three patients (5%) exhibited heterotopic ossification. Quality of life was evaluated with the SF36. The physical component increased from 29.2 points (range, 18.5 to 46.0) to 51.7 points (range 42.9 to 60.6) and the mental component from 375 points (range, 19.5 to 50.0) to 50 points (range 32,8 to 62.0).
- Published
- 2012
- Full Text
- View/download PDF
38. Somatosensory abnormalities in knee OA.
- Author
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Wylde V, Palmer S, Learmonth ID, and Dieppe P
- Subjects
- Aged, Case-Control Studies, Female, Humans, Hyperalgesia diagnosis, Hyperalgesia epidemiology, Hypesthesia epidemiology, Male, Middle Aged, Osteoarthritis, Knee complications, Osteoarthritis, Knee physiopathology, Pain Threshold physiology, Prevalence, Somatosensory Disorders epidemiology, Surveys and Questionnaires, Thermosensing physiology, Hypesthesia diagnosis, Osteoarthritis, Knee diagnosis, Sensory Thresholds physiology, Somatosensory Disorders diagnosis
- Abstract
Objective: The aim of this study was to use quantitative sensory testing (QST) to explore the range and prevalence of somatosensory abnormalities demonstrated by patients with advanced knee OA., Methods: One hundred and seven knee OA patients and 50 age- and sex-matched healthy participants attended a 1-h QST session. Testing was performed on the medial side of the knee and the pain-free forearm. Light-touch thresholds were assessed using von Frey filaments, pressure pain thresholds using a digital pressure algometer, and thermal sensation and pain thresholds using a Thermotest MSA. Significant differences in median threshold values from knee OA patients and healthy participants were identified using Mann-Whitney U-tests. The z-score transformations were used to determine the prevalence of the different somatosensory abnormalities in knee OA patients., Results: Testing identified 70% of knee OA patients as having at least one somatosensory abnormality. Comparison of median threshold values between knee OA patients and healthy participants revealed that patients had localized thermal and tactile hypoaesthesia and pressure hyperalgesia at the osteoarthritic knee. Tactile hypoaesthesia and pressure hyperalgesia were also present at the pain-free forearm. The most prevalent somatosensory abnormalities were tactile hypoaesthesia and pressure hyperalgesia, evident in between 20 and 34% of patients., Conclusion: This study found that OA patients demonstrate an array of somatosensory abnormalities, of which the most prevalent were tactile hypoaesthesia and pressure hyperalgesia. Further research is now needed to establish the clinical implications of these somatosensory abnormalities.
- Published
- 2012
- Full Text
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39. Conversion of a long distally fixed uncemented revision femoral stem to a proximally fixed implant following fatigue fracture.
- Author
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Young PS, Middleton RG, Learmonth ID, and Minhas TH
- Subjects
- Cementation, Fractures, Stress etiology, Humans, Male, Middle Aged, Periprosthetic Fractures etiology, Postoperative Complications, Prosthesis Failure, Reoperation, Treatment Outcome, Arthroplasty, Replacement, Hip adverse effects, Femur surgery, Fractures, Stress surgery, Hip Prosthesis, Periprosthetic Fractures surgery, Prosthesis Design
- Abstract
There has been increasing focus on bone conservation through proximal fixation in primary hip arthroplasty. However, the debate regarding fixation in revision arthroplasty and which factors influence implant choice remains less clear-cut. We report a case involving fatigue fracture of a long, distally well-fixed, uncemented revision stem. This was revised to a proximally fixed implant. This case highlights a number of issues when considering the choice of implant in hip revision surgery and raises the issue of bone conservation in revision surgery. We would suggest that in both primary and revision hip arthroplasty meticulous pre-operative consideration of the choice of implant should be undertaken, especially in the younger patient with higher expectations and functional demands.
- Published
- 2011
- Full Text
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40. Persistent pain after joint replacement: prevalence, sensory qualities, and postoperative determinants.
- Author
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Wylde V, Hewlett S, Learmonth ID, and Dieppe P
- Subjects
- Aged, Aged, 80 and over, Depression epidemiology, Depression physiopathology, Female, Humans, Male, Obesity epidemiology, Obesity physiopathology, Pain epidemiology, Pain Measurement methods, Pain Threshold physiology, Retrospective Studies, Surveys and Questionnaires, Arthroplasty, Replacement, Ankle adverse effects, Arthroplasty, Replacement, Hip adverse effects, Pain etiology, Postoperative Complications physiopathology
- Abstract
Persistent postsurgical pain is a prevalent but underacknowledged condition. The aim of this study was to assess the prevalence, sensory qualities, and postoperative determinants of persistent pain at 3 to 4years after total knee replacement (TKR) and total hip replacement (THR). Patients completed a questionnaire with included the Western Ontario and McMaster Universities Index of Osteoarthritis (WOMAC) Pain Scale, PainDetect Questionnaire, Short-Form McGill Pain Questionnaire, and questions about general health and socioeconomic status. A total of 632 TKR patients and 662 THR patients completed a questionnaire (response rate of 73%); 44% of TKR patients and 27% of THR patients reported experiencing persistent postsurgical pain of any severity, with 15% of TKR patients and 6% of THR patients reporting severe-extreme persistent pain. The persistent pain was most commonly described as aching, tender, and tiring, and only 6% of TKR patients and 1% of THR patients reported pain that was neuropathic in nature. Major depression and the number of pain problems elsewhere were found to be significant and independent postoperative determinants of persistent postsurgical pain. In conclusion, this study found that persistent postsurgical pain is common after joint replacement, although much of the pain is mild, infrequent, or an improvement on preoperative pain. The association between the number of pain problems elsewhere and the severity of persistent postsurgical pain suggests that patients with persistent postsurgical pain may have an underlying vulnerability to pain. A small percentage of patients have severe persistent pain after joint replacement, and this is associated with depression and the number of pain problems elsewhere., (Copyright © 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.)
- Published
- 2011
- Full Text
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41. Metal-on-metal bearings total hip arthroplasty: the cobalt and chromium ions release concern.
- Author
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Delaunay C, Petit I, Learmonth ID, Oger P, and Vendittoli PA
- Subjects
- Female, Humans, Male, Neoplasms chemically induced, Osteolysis etiology, Prosthesis Design, Risk Factors, Chromium analysis, Chromium toxicity, Cobalt analysis, Cobalt toxicity, Equipment Failure Analysis, Granuloma, Plasma Cell etiology, Hip Prosthesis, Hypersensitivity, Delayed etiology, Ions analysis, Metals toxicity, Vasculitis, Leukocytoclastic, Cutaneous etiology
- Abstract
With certain concerns recently reported on metal-on-metal bearing couples in total hip arthroplasty, this study's objective is to review the current knowledge concerning release of metal ions and its potential consequences. Each metal-on-metal implant presents different tribological properties. The analytical techniques for metals are accurate and the Co ion rates seem acceptable up to 2 μg/L. A delayed type IV hypersensitivity reaction (atypical lymphocytic vasculitis-associated lesion [ALVAL]) may be the source of arthroplasty failure. Idiosyncratic, it remains unpredictable even using cutaneous tests and apparently is rare (0.3%). Today, there are no scientific or epidemiologic data supporting a risk of carcinogenesis or teratogenesis related to the use of a metal-on-metal bearings couple. Solid pseudotumors nearly exclusively are observed with resurfacing procedures, carrying a high annual revision rate in women under 40 years of age, occurring particularly in cases of acetabular malposition and with use of cast molded Cr-Co alloys. Osteolysis manifests through complete and progressive radiolucent lines or through cavitary lesions stemming from ALVAL-type alterations or impingement problems or implant incompatibility. The formation of wear debris exceeding the biological tolerance is possible with implant malposition, subluxation, and jamming of the femoral head in cases of cup deformity. Moreover, each implant presents different metal ion production; assessment of their performance and safety is required before their clinical use. With the knowledge available today, metal-on-metal bearing couples are contraindicated in cases of metal allergies or end stage renal dysfunction and small size resurfacing should cautiously be used., (Copyright © 2010. Published by Elsevier Masson SAS.)
- Published
- 2010
- Full Text
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42. Unstated factors in orthopaedic decision-making: a qualitative study.
- Author
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Gooberman-Hill R, Sansom A, Sanders CM, Dieppe PA, Horwood J, Learmonth ID, Williams S, and Donovan JL
- Subjects
- Aged, Arthroplasty, Replacement, Hip psychology, Arthroplasty, Replacement, Knee psychology, Clinical Protocols standards, Female, Humans, Male, Middle Aged, Orthopedics methods, Arthroplasty, Replacement, Hip standards, Arthroplasty, Replacement, Knee standards, Decision Making, Orthopedics standards, Physician-Patient Relations ethics, Practice Patterns, Physicians' trends
- Abstract
Background: Total joint replacement (TJR) of the hip or knee for osteoarthritis is among the most common elective surgical procedures. There is some inequity in provision of TJR. How decisions are made about who will have surgery may contribute to disparities in provision. The model of shared decision-making between patients and clinicians is advocated as an ideal by national bodies and guidelines. However, we do not know what happens within orthopaedic practice and whether this reflects the shared model. Our study examined how decisions are made about TJR in orthopaedic consultations., Methods: The study used a qualitative research design comprising semi-structured interviews and observations. Participants were recruited from three hospital sites and provided their time free of charge. Seven clinicians involved in decision-making about TJR were approached to take part in the study, and six agreed to do so. Seventy-seven patients due to see these clinicians about TJR were approached to take part and 26 agreed to do so. The patients' outpatient appointments ('consultations') were observed and audio-recorded. Subsequent interviews with patients and clinicians examined decisions that were made at the appointments. Data were analysed using thematic analysis., Results: Clinical and lifestyle factors were central components of the decision-making process. In addition, the roles that patients assigned to clinicians were key, as were communication styles. Patients saw clinicians as occupying expert roles and they deferred to clinicians' expertise. There was evidence that patients modified their behaviour within consultations to complement that of clinicians. Clinicians acknowledged the complexity of decision-making and provided descriptions of their own decision-making and communication styles. Patients and clinicians were aware of the use of clinical and lifestyle factors in decision-making and agreed in their description of clinicians' styles. Decisions were usually reached during consultations, but patients and clinicians sometimes said that treatment decisions had been made beforehand. Some patients expressed surprise about the decisions made in their consultations, but this did not necessarily imply dissatisfaction., Conclusions: The way in which roles and communication are played out in decision-making for TJR may affect the opportunity for shared decisions. This may contribute to variation in the provision of TJR. Making the importance of these factors explicit and highlighting the existence of patients' 'surprise' about consultation outcomes could empower patients within the decision-making process and enhance communication in orthopaedic consultations.
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- 2010
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43. Evaluation of the Personal Impact Health Assessment Questionnaire (PI HAQ) to capture the impact of disability in osteoarthritis.
- Author
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Wylde V, Livesey C, Learmonth ID, Blom AW, and Hewlett S
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Osteoarthritis rehabilitation, Pain, Range of Motion, Articular, Severity of Illness Index, Social Support, Surveys and Questionnaires, Activities of Daily Living psychology, Disability Evaluation, Health Status Indicators, Osteoarthritis physiopathology, Osteoarthritis psychology, Quality of Life psychology
- Abstract
Aim: Measuring facts about disability may not reflect their personal impact. An individualized values instrument has been used to weight difficulty in performing activities of daily living in rheumatoid arthritis, and calculate personal impact (Personal Impact Health Assessment Questionnaire; PI HAQ). This study aimed to evaluate the PI HAQ in osteoarthritis (OA)., Study Design: Study 1: 51 people with OA completed short and long versions of the value instrument at 0 and 1 week. Study 2: 116 people with OA completed the short value instrument, disability and psychological measures at 0 and 4 weeks., Results: Study 1: The eight-category and 20-item value instruments correlated well (r = 0.85) and scores differed by just 2.7%. The eight-category instrument showed good internal consistency reliability (Cronbach's alpha = 0.85) and moderate one-week test-retest reliability (r = 0.68, Wilcoxon signed-rank test p = 0.16, intra-class correlation coefficient [ICC] 0.62). Study 2: Values for disability were not associated with disability severity or clinical status. After weighting disability by value, the resulting PI HAQ scores were significantly associated with dissatisfaction with disability, perceived increase in disability, poor clinical status and life dissatisfaction, and differed significantly between people with high and low clinical status (convergent and discriminant construct validity). There was moderate association with the disease repercussion profile disability subscale (r = 0.511; p < 0.001) (criterion validity). The PI HAQ was stable over four weeks (ICC 0.81)., Conclusions: These studies provide an initial evaluation of an instrument to measure the personal impact of disability in people with OA, setting disability within a personal context. Further studies, including sensitivity to change, are required.
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- 2010
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44. Determination of digitised radiograph magnification factors for pre-operative templating in hip prosthesis surgery.
- Author
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Descamps S, Livesey C, and Learmonth ID
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Preoperative Care methods, Prognosis, Reproducibility of Results, Sensitivity and Specificity, Young Adult, Arthroplasty, Replacement, Hip methods, Hip Joint diagnostic imaging, Hip Joint surgery, Radiographic Image Enhancement methods, Radiographic Image Interpretation, Computer-Assisted methods
- Abstract
Objective: With digital radiography development, information technology (IT) companies have developed specific software for templating procedures, requiring individual magnification assessments for each patient. The aim of this study was to determine the mean magnification factor of digital radiographs and to evaluate the possibility of using the mean magnification factor or clinical information in templating., Materials and Methods: We retrospectively evaluated 100 primary total hip arthroplasty digital radiographs using the femoral head prosthesis as a calliper to determinate the mean magnification factor. Working on the assumption that altitude of the hip during radiograph is decisive in modification of magnification factors, we also looked for a correlation between weight, body mass index (BMI), altitude and magnification factor., Results: The magnification factor was 126% (121-130%). A relationship was found between magnification factor (Mf) and weight (Mf = 7.10(-4)x weight (kg) + 1.21), but not BMI. In 98% of cases, if the weight-correlated formula is used, the sizing is correct or the error is +/- 1 mm. With the mean method the sizing is correct or within 1 mm in only 78.2% of cases., Conclusion: Levels of accuracy for the mean magnification factor and the weight-correlated formula are not as high as individual assessments using a calliper; however, they could be used in everyday practice where individual magnification factors have not been calculated.
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- 2010
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45. Conservative stems in total hip replacement.
- Author
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Learmonth ID
- Subjects
- Arthroplasty, Replacement, Hip methods, Humans, Prosthesis Failure, Arthroplasty, Replacement, Hip instrumentation, Osteotomy methods, Prosthesis Design
- Abstract
Arthritis of the hip primarily involves the joint surfaces. Intuitively the principal objective in the surgical management of arthritis is to replace the damaged articular surfaces. However, early attempts at conservative replacement failed both because of inadequate fixation and failure of the articulation.Conservative hip implants take less bone at the time of surgery and preserve bone in the longer term with more physiological loading. In addition, the implants are usually easier to insert with soft tissue sparing surgery. While these implants potentially offer an additional option in the surgical management of younger patients with arthritis, this advantage is negated if there is an unacceptably high incidence of premature failure. This paper explores the evolution and results of conservative total hip prostheses that culminated in the contemporary designs.
- Published
- 2009
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46. Use of irradiated bone graft for impaction grafting in acetabular revision surgery: a review of fifty consecutive cases.
- Author
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Mehendale S, Learmonth ID, Smith EJ, Nedungayil S, Maheshwari R, and Hassaballa MA
- Subjects
- Aged, Female, Follow-Up Studies, Humans, Male, Middle Aged, Reoperation methods, Retrospective Studies, Tissue and Organ Harvesting methods, Arthroplasty, Replacement, Hip methods, Bone Regeneration radiation effects, Bone Transplantation methods, Sterilization methods
- Abstract
Impaction bone grafting is a useful technique in the armament of a revision hip surgeon. Traditionally fresh frozen allograft has been used for this technique. However there are concerns about the transmission of viral proteins and prions through this form of allograft. As a result irradiated bone graft has been favoured in some centres. There is no long term series describing the results of impaction bone grafting using irradiated bone. This paper reviews a consecutive series of 50 cases of acetabular revision surgery performed between 1995 and 2001 and followed up over a mean period of 45 months. The preoperative bone defect was graded by the Paprosky classification. There were 2 cases of type 1a, 9 type 2a, 15 type 2b, 7 type 2c, 10 type 3a and 7 type 3b. All cases were followed up clinically and radiologically. Case notes were reviewed for primary prosthesis, operative details and reason for revision. The radiographs were evaluated for signs of bone incorporation, remodelling, loosening and migration of the acetabular component. There were 5 cases of aseptic loosening at the end of the follow up period. One patient had recurrent dislocation and was revised. 20 cases (40%) showed changes suggestive of bone incorporation, while only 3 cases (6%) showed remodelling. Clinically a good or excellent outcome with absence of pain was achieved in 35 patients (70%). The results suggested that acetabular impaction bone grafting using irradiated bone graft is comparable to fresh frozen allograft. The low percentage of remodelling remains a concern and warrants further studies.
- Published
- 2009
- Full Text
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47. A new short uncemented, proximally fixed anatomic femoral implant with a prominent lateral flare: design rationals and study design of an international clinical trial.
- Author
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Renkawitz T, Santori FS, Grifka J, Valverde C, Morlock MM, and Learmonth ID
- Subjects
- Adolescent, Adult, Aged, Arthroplasty, Replacement, Hip methods, Biomechanical Phenomena, Bone Cements, Femur Head physiology, Germany, Humans, Italy, Middle Aged, Prospective Studies, Prosthesis Design instrumentation, Quality of Life, Spain, United Kingdom, Young Adult, Arthroplasty, Replacement, Hip instrumentation, Femur Head surgery, Hip Prosthesis, Product Surveillance, Postmarketing, Prosthesis Design methods
- Abstract
Background: Anatomic short femoral prostheses with a prominent lateral flare have the potential to reduce stress-shielding in the femur through a more physiological stress distribution to the proximal femur. We present the design rationale of a new short uncemented, proximally fixed anatomic femoral implant and the study design of a prospective multi-centre trial to collect long-term patient outcome and radiographic follow up data., Methods: A prospective surveillance study (trial registry NCT00208555) in four European centres (UK, Italy, Spain and Germany) with a follow up period of 15 years will be executed. The recruitment target is 200 subjects, patients between the ages of 18 and 70 admitted for primary cementless unilateral THA will be included. The primary objective is to evaluate the five-year survivorship of the new cementless short stem. The secondary objectives of this investigation are to evaluate the long term survivorship and the clinical performance of the implant, the impact on the subjects health related Quality of Life and the affect of the prosthesis on bone mineral density. Peri- and postoperative complications will be registered. Clinical and radiographic evaluation of prosthesis positioning will be done post-operatively and at 3, 6, 12, 24, 60, 120 and 180 months follow up., Discussion: Shortening of the distal stem can maximise bone and soft tissue conservation. New stem types have been designed to improve the limitations of traditional implants in primary THA. A new, uncemented femoral short stem is introduced in this paper. A long-term follow up study has been designed to verify stable fixation and to research into the clinical outcome. The results of this trial will be presented as soon as they become available.
- Published
- 2008
- Full Text
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48. A systematic comparison of the actual, potential, and theoretical health effects of cobalt and chromium exposures from industry and surgical implants.
- Author
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Keegan GM, Learmonth ID, and Case CP
- Subjects
- Chemical Industry, Humans, Immune System drug effects, Mutagenicity Tests, Neoplasms chemically induced, Oxidative Stress, Reproduction drug effects, Risk Factors, Arthroplasty, Replacement adverse effects, Chromium toxicity, Cobalt toxicity, Environmental Pollutants toxicity
- Abstract
Humans are exposed to cobalt (Co) and chromium (Cr) from industry and surgical devices, most notably orthopedic joint replacements. This review compares the potential health effects of exposure to Co and Cr contaminants from these two different sources, both in the locally exposed tissues and at sites distant to the primary exposure. Surgical implantation results largely in exposures to ions, corrosion products, and particles of Co and Cr. Industrial exposures are predominantly to metal compounds and particles. Although there are large literatures on industrial and surgical exposures to these metals, there has yet to be a systematic comparison of the two to test whether more general lessons might be learned about the human toxicology of Co and Cr. Both industrial and surgical exposures cause inflammatory and other immune reactions in the directly exposed tissues. In the lung there is a well-established risk of cancer following long-term exposures to hexavalent Cr; however, the development of sarcoma in the connective tissues adjacent to implants in response to metal particles is rare. Both types of exposure are associated with changes in the peripheral blood, including evidence of oxidative stress, and altered numbers of circulating immune cells. There is dissemination of Co and Cr to sites distant to the orthopedic implant, but less is known about systemic dissemination of these metals away from the lung. The effects of industrial exposures in the reproductive, renal, and cardiac systems have been investigated, but this has yet to be explored after surgical exposures. The form of the metal (and associated elements) in both instances is key to the toxicological effects arising in the body and further characterization of debris released from devices is certainly recommended, as is the impact of nanotoxicology on the health and safety of workers and patients. Biomonitoring schemes currently used in industry could be translated, if required, into suitable programs for orthopedic out-patients. Cross-communication between experts in industrial and occupational medicine and regulatory agencies may be useful.
- Published
- 2008
- Full Text
- View/download PDF
49. Total knee replacement: is it really an effective procedure for all?
- Author
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Wylde V, Dieppe P, Hewlett S, and Learmonth ID
- Subjects
- Activities of Daily Living, Arthralgia epidemiology, Arthroplasty, Replacement, Knee statistics & numerical data, Humans, Pain Measurement, Patient Satisfaction, Quality of Life, Sports, Arthroplasty, Replacement, Knee adverse effects, Outcome Assessment, Health Care
- Abstract
Total knee replacement (TKR) is considered an effective intervention for the treatment of chronic knee pain and disability. Yet there is increasing evidence, based on research using patient-based outcome measures, that a significant proportion of patients experience chronic knee pain, functional disability, a poor quality of life and dissatisfaction after TKR. Although some poor outcomes after TKR are due to surgical technique and implant factors, much of the pain and disability after surgery is medically unexplained. A range of possible patient factors could contribute to a poor outcome after TKR. Socio-demographic factors that have been found to correlate with a poor outcome after TKR include female gender, older age and low socio-economical status. Medical factors that are highly predictive of pain and disability after TKR are a greater number of co-morbidities and a worse pre-operative status. A range of psychological factors could be predictive of a poor outcome after surgery including depression, low self-efficacy, poor pain coping strategies, somatization, low social support and patient expectations. It is also proposed that a biological explanation for continuing pain after TKR could involve central sensitisation, a dysfunction of pain modulation by the central nervous system. To improve patient selection for TKR, future research needs to focus on developing a pre-operative screening protocol to identify those patients at risk of medically unexplained pain and disability after TKR.
- Published
- 2007
- Full Text
- View/download PDF
50. Precision of wear measurement using the shadowgraph technique.
- Author
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Cunningham JL, Bisbinas I, Greenwood R, and Learmonth ID
- Subjects
- Equipment Design, Reproducibility of Results, Sensitivity and Specificity, Surface Properties, Equipment Failure Analysis methods, Hip Prosthesis, Image Interpretation, Computer-Assisted methods, Photography methods
- Abstract
The shadowgraph technique is a relatively easy-to-use and inexpensive method of wear measurement from explanted acetabular cups. In this technique, from a mould of the internal surface of the cup, measurements of linear wear and wear angle can be obtained, from which volumetric wear can be calculated. In this study the measurement precision of this technique was assessed and the influence of different observers and multiple moulds was also determined. It was found that linear wear (coefficient of variation (CV) = 1.49 per cent) can be more precisely determined than wear angle (CV = 8.18 per cent) and that both the observer and the mould can significantly influence the results obtained, although the influence of the mould is considerably less than that of the observer.
- Published
- 2007
- Full Text
- View/download PDF
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