76
|
Mills L, Tsang J, Hopper G, Keenan G, Simpson AHRW. The multifactorial aetiology of fracture nonunion and the importance of searching for latent infection. Bone Joint Res 2016; 5:512-519. [PMID: 27784669 PMCID: PMC5108351 DOI: 10.1302/2046-3758.510.bjr-2016-0138] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Objectives A successful outcome following treatment of nonunion requires the correct identification of all of the underlying cause(s) and addressing them appropriately. The aim of this study was to assess the distribution and frequency of causative factors in a consecutive cohort of nonunion patients in order to optimise the management strategy for individual patients presenting with nonunion. Methods Causes of the nonunion were divided into four categories: mechanical; infection; dead bone with a gap; and host. Prospective and retrospective data of 100 consecutive patients who had undergone surgery for long bone fracture nonunion were analysed. Results A total of 31% of patients had a single attributable cause, 55% had two causes, 14% had three causes and 1% had all four. Of those (31%) with only a single attributable cause, half were due to a mechanical factor and a quarter had dead bone with a gap. Mechanical causation was found in 59% of all patients, dead bone and a gap was present in 47%, host factors in 43% and infection was a causative factor in 38% of patients. In all, three of 58 patients (5%) thought to be aseptic and two of nine (22%) suspected of possible infection were found to be infected. A total of 100% of previously treated patients no longer considered to have ongoing infection, had multiple positive microbiology results. Conclusion Two thirds of patients had multiple contributing factors for their nonunion and 5% had entirely unexpected infection. This study highlights the importance of identifying all of the aetiological factors and routinely testing tissue for infection in treating nonunion. It raises key points regarding the inadequacy of a purely radiographic nonunion classification system and the variety of different definitions for atrophic nonunion in the current mainstream classifications used for nonunion. Cite this article: L. Mills, J. Tsang, G. Hopper, G. Keenan, A. H. R. W. Simpson. The multifactorial aetiology of fracture nonunion and the importance of searching for latent infection. Bone Joint Res 2016;5:512–519. DOI: 10.1302/2046-3758.510.BJR-2016-0138.
Collapse
|
77
|
Kuske B, Hamilton DF, Pattle SB, Simpson AHRW. Patterns of Hamstring Muscle Tears in the General Population: A Systematic Review. PLoS One 2016; 11:e0152855. [PMID: 27144648 PMCID: PMC4856270 DOI: 10.1371/journal.pone.0152855] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 03/21/2016] [Indexed: 11/18/2022] Open
Abstract
Background Hamstring tears are well recognised in the sporting population. Little is known about these injuries in the general population. Purpose Evaluating the rates, patterns and risk factors of non-sporting hamstring tears, compared to sporting related hamstring tears. Data Sources MEDLINE, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials (1989–2015). Study Selection Studies reporting patients with a grade 2 or 3 hamstring muscle tear, identified clinically, confirmed by MRI imaging or direct visualisation during surgical exploration. Data Synthesis 144 sets of linked data were extracted for analysis. Most injuries were in males (81.3%), where mean age at injury was lower (30.2, 95% CI 29.1–31.3) than in females (35.4, 95% CI 32.4–38.4) p = 0.06. Key differences were found in the proportion of non-sporting injuries in patients under and over the age 40 (p = 0.001). The proportion of non-sporting injuries was significantly higher in females compared to males (25.9% female non-sporting injuries, versus 8.5% male; p = 0.02). Avulsions were more frequently reported in non-sporting activities (70.5%). The proportion of such injuries was notably higher in females, though this failed to meet significance (p = 0.124). Grouped by age category a bimodal distribution was noted, with the proportion of avulsions greater in younger (age <15) and older patients (age > 40) (p = 0.008). 86.8% of patients returned to pre-injury activity levels with a similar frequency across all study variables; age, activity (sporting vs non-sporting) and injury type (avulsion vs tear). Conclusion This review highlights a proportion of adults suffering grade 2 or 3 hamstring injuries from activities other than the classic sports trauma. The majority of these non-sporting injuries were avulsion injuries that clustered in older female and skeletally immature patients suggesting a potential link to bone mineral density.
Collapse
|
78
|
Paterson SI, Eltawil NM, Simpson AHRW, Amin AK, Hall AC. Drying of open animal joints in vivo subsequently causes cartilage degeneration. Bone Joint Res 2016; 5:137-44. [PMID: 27114348 PMCID: PMC4921049 DOI: 10.1302/2046-3758.54.2000594] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 02/26/2016] [Indexed: 02/03/2023] Open
Abstract
Objectives During open orthopaedic surgery, joints may be exposed to air, potentially leading to cartilage drying and chondrocyte death, however, the long-term effects of joint drying in vivo are poorly understood. We used an animal model to investigate the subsequent effects of joint drying on cartilage and chondrocytes. Methods The patellar groove of anaesthetised rats was exposed (sham-operated), or exposed and then subjected to laminar airflow (0.25m/s; 60 minutes) before wounds were sutured and animals recovered. Animals were monitored for up to eight weeks and then sacrificed. Cartilage and chondrocyte properties were studied by histology and confocal microscopy, respectively. Results Joint drying caused extensive chondrocyte death within the superficial regions of cartilage. Histology of dried cartilage demonstrated a loss of surface integrity at four weeks, fibrillations at eight weeks, and an increased modified Mankin score (p < 0.001). Cartilage thickness increased (p < 0.001), whereas chondrocyte density decreased at four weeks (p < 0.001), but then increased towards sham-operated levels (p < 0.01) at eight weeks. By week eight, chondrocyte pairing/clustering and cell volume increased (p < 0.05; p < 0.001, respectively). Conclusions These in vivo results demonstrated for the first time that as a result of laminar airflow, cartilage degeneration occurred which has characteristics similar to those seen in early osteoarthritis. Maintenance of adequate cartilage hydration during open orthopaedic surgery is therefore of paramount importance. Cite this article: Dr A. Hall. Drying of open animal joints in vivo subsequently causes cartilage degeneration. Bone Joint Res 2016;5:137–144. DOI: 10.1302/2046-3758.54.2000594.
Collapse
|
79
|
Leow JM, Clement ND, Tawonsawatruk T, Simpson CJ, Simpson AHRW. The radiographic union scale in tibial (RUST) fractures: Reliability of the outcome measure at an independent centre. Bone Joint Res 2016; 5:116-21. [PMID: 27073210 PMCID: PMC5009237 DOI: 10.1302/2046-3758.54.2000628] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 02/26/2016] [Indexed: 01/09/2023] Open
Abstract
Objectives The radiographic union score for tibial (RUST) fractures was developed by Whelan et al to assess the healing of tibial fractures following intramedullary nailing. In the current study, the repeatability and reliability of the RUST score was evaluated in an independent centre (a) using the original description, (b) after further interpretation of the description of the score, and (c) with the immediate post-operative radiograph available for comparison. Methods A total of 15 radiographs of tibial shaft fractures treated by intramedullary nailing (IM) were scored by three observers using the RUST system. Following discussion on how the criteria of the RUST system should be implemented, 45 sets (i.e. AP and lateral) of radiographs of IM nailed tibial fractures were scored by five observers. Finally, these 45 sets of radiographs were rescored with the baseline post-operative radiograph available for comparison. Results The initial intraclass correlation (ICC) on the first 15 sets of radiographs was 0.67 (95% CI 0.63 to 0.71). However, the original description was being interpreted in different ways. After agreeing on the interpretation, the ICC on the second cohort improved to 0.75. The ICC improved even further to 0.79, when the baseline post-operative radiographs were available for comparison. Conclusion This study demonstrates that the RUST scoring system is a reliable and repeatable outcome measure for assessing tibial fracture healing. Further improvement in the reliability of the scoring system can be obtained if the radiographs are compared with the baseline post-operative radiographs. Cite this article: Mr J.M. Leow. The radiographic union scale in tibial (RUST) fractures: Reliability of the outcome measure at an independent centre. Bone Joint Res 2016;5:116–121. DOI: 10.1302/2046-3758.54.2000628.
Collapse
|
80
|
Lin YC, Hall AC, Smith IDM, Salter DM, Simpson AHRW. Mapping Chondrocyte Viability, Matrix Glycosaminoglycan, and Water Content on the Surface of a Bovine Metatarsophalangeal Joint. Cartilage 2016; 7:193-203. [PMID: 27047642 PMCID: PMC4797237 DOI: 10.1177/1947603515613848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE The purpose of this study was to determine if there were variations in chondrocyte viability, matrix glycosaminoglycan (GAG), and water content between different areas of the articular surface of a bovine metatarsophalangeal joint, a common and reliable source of articular cartilage for experimental study, which may compromise the validity of using multiple samples from different sites within the joint. METHODS Nine fresh cadaveric bovine metatarsophalangeal joints were obtained. From each joint, 16 osteochondral explants were taken from 4 facets, yielding a total of 144 cartilage specimens for evaluation of chondrocyte viability, matrix GAG, and water content. A less invasive method for harvesting osteochondral explants and for processing the biopsy for the assessment of chondrocyte viability was developed, which maintained maximal viability within each cartilage explant. RESULTS There was no significant difference between the 16 biopsy sites from the different areas of the joint surface with respect to chondrocyte viability, matrix GAG and water content. Pooled data of all samples from each joint established the baseline values of chondrocyte viability to be 89.4% ± 3.8%, 94.4% ± 2.2%, and 77.9% ± 7.8%, in the superficial quarter, central half, and deep quarter (with regard to depth from the articular surface), respectively. The matrix GAG content of bovine articular cartilage was 6.06 ± 0.41 μg/mg cartilage, and the cartilage water content was 72.4% ± 1.5%. There were also no significant differences of these 3 variables between the different joints. CONCLUSION It is thus reasonable to compare biopsies obtained from different sites, as a biopsy from one site would be considered representative of the whole joint.
Collapse
|
81
|
Hamilton DF, Giesinger JM, MacDonald DJ, Simpson AHRW, Howie CR, Giesinger K. Responsiveness and ceiling effects of the Forgotten Joint Score-12 following total hip arthroplasty. Bone Joint Res 2016; 5:87-91. [PMID: 26965167 PMCID: PMC4852794 DOI: 10.1302/2046-3758.53.2000480] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
OBJECTIVES To assess the responsiveness and ceiling/floor effects of the Forgotten Joint Score -12 and to compare these with that of the more widely used Oxford Hip Score (OHS) in patients six and 12 months after primary total hip arthroplasty. METHODS We prospectively collected data at six and 12 months following total hip arthroplasty from 193 patients undergoing surgery at a single centre. Ceiling effects are outlined with frequencies for patients obtaining the lowest or highest possible score. Change over time from six months to 12 months post-surgery is reported as effect size (Cohen's d). RESULTS The mean OHS improved from 40.3 (sd 7.9) at six months to 41.9 (sd 7.2) at 12 months. The mean FJS-12 improved from 56.8 (sd 30.1) at six months to 62.1 (sd 29.0) at 12 months. At six months, 15.5% of patients reached the best possible score (48 points) on the OHS and 8.3% obtained the best score (100 points) on the FJS-12. At 12 months, this percentage increased to 20.8% for the OHS and to 10.4% for the FJS-12. In terms of the effect size (Cohen's d), the change was d = 0.10 for the OHS and d = 0.17 for the FJS-12. CONCLUSIONS The FJS-12 is more responsive to change between six and 12 months following total hip arthroplasty than is the OHS, with the measured ceiling effect for the OHS twice that of the FJS-12. The difference in effect size of change results in substantial differences in required sample size if aiming to detect change between these two time points. This has important implications for powering clinical trials with patient-reported measures as the primary outcome.Cite this article: Dr D. F. Hamilton. Responsiveness and ceiling effects of the Forgotten Joint Score-12 following total hip arthroplasty. Bone Joint Res 2016;5:87-91. DOI: 10.1302/2046-3758.53.2000480.
Collapse
|
82
|
Scott EEF, Hamilton DF, Wallace RJ, Muir AY, Simpson AHRW. Increased risk of muscle tears below physiological temperature ranges. Bone Joint Res 2016; 5:61-5. [PMID: 26883967 PMCID: PMC4852792 DOI: 10.1302/2046-3758.52.2000484] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Objectives Temperature is known to influence muscle physiology, with the velocity of shortening, relaxation and propagation all increasing with temperature. Scant data are available, however, regarding thermal influences on energy required to induce muscle damage. Methods Gastrocnemius and soleus muscles were harvested from 36 male rat limbs and exposed to increasing impact energy in a mechanical test rig. Muscle temperature was varied in 5°C increments, from 17°C to 42°C (to encompass the in vivo range). The energy causing non-recoverable deformation was recorded for each temperature. A measure of tissue elasticity was determined via accelerometer data, smoothed by low-pass fifth order Butterworth filter (10 kHz). Data were analysed using one-way analysis of variance (ANOVA) and significance was accepted at p = 0.05. Results The energy required to induce muscle failure was significantly lower at muscle temperatures of 17°C to 32°C compared with muscle at core temperature, i.e., 37°C (p < 0.01). During low-energy impacts there were no differences in muscle elasticity between cold and warm muscles (p = 0.18). Differences in elasticity were, however, seen at higher impact energies (p < 0.02). Conclusion Our findings are of particular clinical relevance, as when muscle temperature drops below 32°C, less energy is required to cause muscle tears. Muscle temperatures of 32°C are reported in ambient conditions, suggesting that it would be beneficial, particularly in colder environments, to ensure that peripheral muscle temperature is raised close to core levels prior to high-velocity exercise. Thus, this work stresses the importance of not only ensuring that the muscle groups are well stretched, but also that all muscle groups are warmed to core temperature in pre-exercise routines. Cite this article: Professor A. H. R. W. Simpson. Increased risk of muscle tears below physiological temperature ranges. Bone Joint Res 2016;5:61–65. DOI: 10.1302/2046-3758.52.2000484.
Collapse
|
83
|
|
84
|
Tsang STJ, Mills LA, Baren J, Frantzias J, Keating JF, Simpson AHRW. Exchange nailing for femoral diaphyseal fracture non-unions: Risk factors for failure. Injury 2015; 46:2404-9. [PMID: 26489394 DOI: 10.1016/j.injury.2015.09.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 09/25/2015] [Accepted: 09/28/2015] [Indexed: 02/02/2023]
Abstract
The aim of this study was to identify risk factors for failure of exchange nailing for femoral diaphyseal fracture non-unions. The study cohort comprised 40 patients with femoral diaphyseal non-unions treated by exchange nailing, of which six were open injuries. The median time to exchange nailing from primary fixation was 8.4 months. The main outcome measures were union, number of secondary fixation procedures required to achieve union and time to union. Multiple causes for non-union were found in 16 (40%) cases, with infection present in 12 (30.0%) patients. Further surgical procedures were required in nine (22.5%) cases, one of whom (2.5%) required the use of another fixation modality to achieve union. Union was ultimately achieved with exchange nailing in 34/37 (91.9%) patients. The median time to union after the exchange nailing was 9.4 months. Cigarette smoking and infection were risk factors for failure of exchange nailing. Multivariate analysis found infection to be the strongest predictor of exchange failure (p<0.05). Exchange nailing is an effective treatment for aseptic femoral diaphyseal fracture non-union. However, 50% of patients undergoing exchange nailing in the presence of infection required at least one further procedure. It is important to counsel patients of this so that they can plan for it and do not consider that the first exchange operation has failed.
Collapse
|
85
|
|
86
|
Hamilton DF, Giesinger JM, Patton JT, MacDonald DJ, Simpson AHRW, Howie CR, Giesinger K. Making the Oxford Hip and Knee Scores meaningful at the patient level through normative scoring and registry data. Bone Joint Res 2015; 4:137-44. [PMID: 26311163 PMCID: PMC4561372 DOI: 10.1302/2046-3758.48.2000524] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Objectives The Oxford Hip and Knee Scores (OHS, OKS) have been demonstrated
to vary according to age and gender, making it difficult to compare
results in cohorts with different demographics. The aim of this
paper was to calculate reference values for different patient groups
and highlight the concept of normative reference data to contextualise an
individual’s outcome. Methods We accessed prospectively collected OHS and OKS data for patients
undergoing lower limb joint arthroplasty at a single orthopaedic
teaching hospital during a five-year period.
T-scores were calculated based on the OHS and OKS distributions. Results Data were obtained from 3203 total hip arthroplasty (THA) patients
and 2742 total knee arthroplasty (TKA) patients. The mean age of
the patient was 68.0 years (sd 11.3, 58.4% women) in the
THA group and in 70.2 (sd 9.4; 57.5% women) in the TKA
group. T-scores were calculated for age and gender subgroups by
operation. Different T-score thresholds are seen at different time
points pre and post surgery. Values are further stratified by operation (THA/TKA)
age and gender. Conclusions Normative data interpretation requires a fundamental shift in
the thinking as to the use of the Oxford Scores. Instead of reporting
actual score points, the patient is rated by their relative position
within the group of all patients undergoing the same procedure.
It is proposed that this form of transformation is beneficial (a)
for more appropriately comparing different patient cohorts and (b)
informing an individual patient how they are progressing compared
with others of their age and gender. Cite this article: Bone Joint Res 2015;4:137–144
Collapse
|
87
|
Hamilton DF, Howie CR, Burnett R, Simpson AHRW, Patton JT. Dealing with the predicted increase in demand for revision total knee arthroplasty: challenges, risks and opportunities. Bone Joint J 2015; 97-B:723-8. [PMID: 26033049 DOI: 10.1302/0301-620x.97b6.35185] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Worldwide rates of primary and revision total knee arthroplasty (TKA) are rising due to increased longevity of the population and the burden of osteoarthritis. Revision TKA is a technically demanding procedure generating outcomes which are reported to be inferior to those of primary knee arthroplasty, and with a higher risk of complication. Overall, the rate of revision after primary arthroplasty is low, but the number of patients currently living with a TKA suggests a large potential revision healthcare burden. Many patients are now outliving their prosthesis, and consideration must be given to how we are to provide the necessary capacity to meet the rising demand for revision surgery and how to maximise patient outcomes. The purpose of this review was to examine the epidemiology of, and risk factors for, revision knee arthroplasty, and to discuss factors that may enhance patient outcomes.
Collapse
|
88
|
Leung AHC, Hawthorn BR, Simpson AHRW. The Effectiveness of Local Antibiotics in Treating Chronic Osteomyelitis in a Cohort of 50 Patients with an Average of 4 Years Follow-Up. Open Orthop J 2015; 9:372-8. [PMID: 26322143 PMCID: PMC4549894 DOI: 10.2174/1874325001509010372] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Revised: 04/26/2015] [Accepted: 05/18/2015] [Indexed: 11/22/2022] Open
Abstract
The treatment of chronic osteomyelitis requires both appropriate surgical and antibiotic management. Prolonged intravenous antibiotic therapy followed by oral therapy is widely utilised. Despite this, the long-term recurrence rate can be up to 30%. A cohort of 50 patients from a 7-year period, 2003 to 2010, with chronic osteomyelitis was identified. This cohort was treated by surgical marginal resection in combination with local application of antibiotics (Collatamp G - gentamicin in a collagen fleece), a short course of systemic antibiotics post-operatively and conversion to oral antibiotics on discharge. Information was retrieved from case notes and computerized records. Outcomes from this cohort were compared with a historical cohort treated with marginal resection followed by 6 weeks of systemic antibiotics and 6 weeks of oral antibiotics. The mean follow-up duration was 3.2 years (SD 1.8). The average length of admission was 9.8 days (SD 11.4). 6 patients (12%) suffered recurrence of infection requiring further treatment. We used the Cierny and Mader classification to stratify the patients. 'A' hosts had a shorter duration of admission (7.1 days) than 'B' hosts (12.3 days). There was no significant difference between recurrence rates of 'A' and 'B' hosts. Where available, we found pre-operative C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) levels had no correlation with disease recurrence. Disease-free probability for this cohort compared favourably with the historical cohort. We believe local administration of gentamicin in a collagen fleece is a useful component in the management of chronic osteomyelitis.
Collapse
|
89
|
Simpson AHRW. Orthopaedic journals, impact factors, research impact and research quality. Bone Joint Res 2015; 4:117-9. [PMID: 26184104 PMCID: PMC4678364 DOI: 10.1302/2046-3758.47.2000488] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 05/20/2015] [Indexed: 12/20/2022] Open
|
90
|
Savaridas T, Wallace RJ, Dawson S, Simpson AHRW. Effect of ibandronate on bending strength and toughness of rodent cortical bone: Possible implications for fracture prevention. Bone Joint Res 2015; 4:99-104. [PMID: 26062566 PMCID: PMC4468982 DOI: 10.1302/2046-3758.46.2000311] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Objectives There remains conflicting evidence regarding cortical bone strength
following bisphosphonate therapy. As part of a study to assess the
effects of bisphosphonate treatment on the healing of rat tibial
fractures, the mechanical properties and radiological density of
the uninjured contralateral tibia was assessed. Methods Skeletally mature aged rats were used. A total of 14 rats received
1µg/kg ibandronate (iban) daily and 17 rats received 1 ml 0.9% sodium
chloride (control) daily. Stress at failure and toughness of the
tibial diaphysis were calculated following four-point bending tests. Results Uninjured cortical bone in the iban group had a significantly
greater mean (standard deviation (sd)), p < 0.001, stress
at failure of 219.2 MPa (sd 45.99) compared with the control
group (169.46 MPa (sd 43.32)) following only nine weeks
of therapy. Despite this, the cortical bone toughness and work to
failure was similar. There was no significant difference in radiological
density or physical dimensions of the cortical bone. Conclusions Iban therapy increases the stress at failure of uninjured cortical
bone. This has relevance when normalising the strength of repair
in a limb when comparing it with the unfractured limb. However,
the 20% increase in stress at failure with iban therapy needs to
be interpreted with caution as there was no corresponding increase
in toughness or work to failure. Further research is required in
this area, especially with the increasing clinical burden of low-energy
diaphyseal femoral fractures following prolonged use of bisphosphonates. Cite this article: Bone Joint Res 2015;4:99–104
Collapse
|
91
|
Hamilton DF, Burnett R, Patton JT, Howie CR, Moran M, Simpson AHRW, Gaston P. Implant design influences patient outcome after total knee arthroplasty: a prospective double-blind randomised controlled trial. Bone Joint J 2015; 97-B:64-70. [PMID: 25568415 DOI: 10.1302/0301-620x.97b1.34254] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Total knee arthroplasty (TKA) is an established and successful procedure. However, the design of prostheses continues to be modified in an attempt to optimise the functional outcome of the patient. The aim of this study was to determine if patient outcome after TKA was influenced by the design of the prosthesis used. A total of 212 patients (mean age 69; 43 to 92; 131 female (62%), 81 male (32%)) were enrolled in a single centre double-blind trial and randomised to receive either a Kinemax (group 1) or a Triathlon (group 2) TKA. Patients were assessed pre-operatively, at six weeks, six months, one year and three years after surgery. The outcome assessments used were the Oxford Knee Score; range of movement; pain numerical rating scales; lower limb power output; timed functional assessment battery and a satisfaction survey. Data were assessed incorporating change over all assessment time points, using repeated measures analysis of variance longitudinal mixed models. Implant group 2 showed a significantly greater range of movement (p = 0.009), greater lower limb power output (p = 0.026) and reduced report of 'worst daily pain' (p = 0.003) over the three years of follow-up. Differences in Oxford Knee Score (p = 0.09), report of 'average daily pain' (p = 0.57) and timed functional performance tasks (p = 0.23) did not reach statistical significance. Satisfaction with outcome was significantly better in group 2 (p = 0.001). These results suggest that patient outcome after TKA can be influenced by the prosthesis used.
Collapse
|
92
|
Blackmur JP, Tang EYH, Dave J, Simpson AHRW. Use of broth cultures peri-operatively to optimise the microbiological diagnosis of musculoskeletal implant infections. Bone Joint J 2015; 96-B:1566-70. [PMID: 25371476 DOI: 10.1302/0301-620x.96b11.33852] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We compared the use of broth culture medium for samples taken in theatre with the standard practice of placing tissue samples in universal containers. A total of 67 consecutive patients had standard multiple samples of deep tissue harvested at surgery and distributed equally in theatre either to standard universal containers or to broth culture medium. These samples were cultured by direct and enrichment methods. The addition of broth in theatre to standard practice led to an increase in sensitivity from 83% to 95% and an increase in negative predictive value from 77% to 91%. Placing tissue samples directly into broth in the operating theatre is a simple, inexpensive way to increase the sensitivity of cultures from infected patients, and does not appear to compromise the specificity of these cultures.
Collapse
|
93
|
MacLeod AR, Simpson AHRW, Pankaj P. Reasons why dynamic compression plates are inferior to locking plates in osteoporotic bone: a finite element explanation. Comput Methods Biomech Biomed Engin 2014; 18:1818-25. [PMID: 25473732 DOI: 10.1080/10255842.2014.974580] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
While locking plate fixation is becoming increasingly popular for complex and osteoporotic fractures, for many indications compression plating remains the standard choice. This study compares the mechanical behaviour of the more recent locking compression plate (LCP) device, with the traditional dynamic compression plates (DCPs) in bone of varying quality using finite element modelling. The bone properties considered include orthotropy, inhomogeneity, cortical thinning and periosteal apposition associated with osteoporosis. The effect of preloads induced by compression plating was included in the models. Two different fracture scenarios were modelled: one with complete reduction and one with a fracture gap. The results show that the preload arising in DCPs results in large principal strains in the bone all around the perimeter of the screw hole, whereas for LCPs large principal strains occur primarily on the side of the screw proximal to the load. The strains within the bone produced by the two screw types are similar in healthy bone with a reduced fracture gap; however, the DCP produces much larger strains in osteoporotic bone. In the presence of a fracture gap, the DCP results in a considerably larger region with high tensile strains and a slightly smaller region with high compressive strains. These findings provide a biomechanical basis for the reported improved performance of locking plates in poorer bone quality.
Collapse
|
94
|
Wallace RJ, Pankaj P, Simpson AHRW. Major source of error when calculating bone mechanical properties. J Bone Miner Res 2014; 29:2697. [PMID: 24986805 DOI: 10.1002/jbmr.2304] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
95
|
Tawonsawatruk T, Hamilton DF, Simpson AHRW. Validation of the use of radiographic fracture-healing scores in a small animal model. J Orthop Res 2014; 32:1117-9. [PMID: 24895294 DOI: 10.1002/jor.22665] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 05/16/2014] [Indexed: 02/04/2023]
Abstract
Precise assessment of fracture-healing is vital in both clinical and research settings, where therapies are typically assessed using animal models with union as the study end point. Radiographic scoring systems have been developed for clinical use; however have not been validated in pre-clinical models. Thirty sets of radiographs of rat tibial shaft fractures, treated with external fixation were reviewed by six observers using the Radiographic Union in Tibia (RUST) scale, the Lane & Sandhu score, and an overall impression of union. Fleiss's kappa and Intra-class Correlation Coefficients (ICC) were used to determine reliability. Inter-observer and intra-observer agreement using the general impression score were moderate [kappa; 0.58; 95%CI (0.49-0.65) and 0.66 (0.43-0.89), respectively]. Inter-observer and intra-observer agreement were excellent using both the RUST score [ICC; 0.81 (0.72-0.89) and 0.86 (0.74-0.93), respectively], and Lane & Sandhu score [ICC; 0.88 (0.81-0.93) and 0.90 (0.81-0.95), respectively]. Employing a defined scoring system enhances both the reproducibility and repeatability of bone healing assessment in a small animal model. Routine reporting of fracture scoring methodology should be encouraged to enrich results and facilitate data synthesis across studies.
Collapse
|
96
|
Clement ND, MacDonald D, Simpson AHRW. The minimal clinically important difference in the Oxford knee score and Short Form 12 score after total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc 2014; 22:1933-9. [PMID: 24253376 DOI: 10.1007/s00167-013-2776-5] [Citation(s) in RCA: 307] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 10/22/2013] [Indexed: 01/18/2023]
Abstract
PURPOSE The aim of this study was to identify the minimal clinically important difference (MCID) in the Oxford knee score (OKS) and Short Form (SF-) 12 score after total knee arthroplasty (TKA). METHODS Prospective pre-operative and 1 year post-operative OKS and SF-12 scores for 505 patients undergoing a primary TKA for osteoarthritis were collected during a one-year period. Patient satisfaction with their (1) patient relief and (2) functional outcome was used as the anchor questions. Their response to each question was recorded using a 5-point Likert scale: excellent, very well, well, fair, and poor. Simple linear regression was used to calculate the MCID for improvement in the OKS and physical component of the SF-12 score according to the level of patient satisfaction with their pain relief and function. RESULTS The OKS improved by 15.5 (95 % CI 14.7-16.4) points and the SF-12 physical component score improved by 10.1 (95 % CI 9.1-11.2) points for the study cohort. The level of patient satisfaction with their pain relief and function correlated with the improvement in the OKS (r = 0.56; p < 0.001, and r = 0.56; p < 0.001) and the physical component of the SF-12 score (r = 0.51; p < 0.001, and r = 0.60; p < 0.001), respectively. The MCID for the OKS was 5.0 (95 % CI 4.4-5.5) and 4.3 (95 % CI 3.8-4.8) points and for the physical component of the SF-12, it was 4.5 (95 % CI 3.9-5.2) and 4.8 (95 % CI 4.2-5.4) points for pain relief and function, respectively. CONCLUSION The MCID identified for the OKS and SF-12 physical component score after TKA is the best available estimate and can be used to power studies and ensure that a statistical difference is also recognised by a patient.
Collapse
|
97
|
Hamilton DF, Lane JV, Gaston P, Patton JT, Macdonald DJ, Simpson AHRW, Howie CR. Assessing treatment outcomes using a single question: the net promoter score. Bone Joint J 2014; 96-B:622-8. [PMID: 24788496 DOI: 10.1302/0301-620x.96b5.32434] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Satisfaction with care is important to both patients and to those who pay for it. The Net Promoter Score (NPS), widely used in the service industries, has been introduced into the NHS as the 'friends and family test'; an overarching measure of patient satisfaction. It assesses the likelihood of the patient recommending the healthcare received to another, and is seen as a discriminator of healthcare performance. We prospectively assessed 6186 individuals undergoing primary lower limb joint replacement at a single university hospital to determine the Net Promoter Score for joint replacements and to evaluate which factors contributed to the response. Achieving pain relief (odds ratio (OR) 2.13, confidence interval (CI) 1.83 to 2.49), the meeting of pre-operative expectation (OR 2.57, CI 2.24 to 2.97), and the hospital experience (OR 2.33, CI 2.03 to 2.68) are the domains that explain whether a patient would recommend joint replacement services. These three factors, combined with the type of surgery undertaken (OR 2.31, CI 1.68 to 3.17), drove a predictive model that was able to explain 95% of the variation in the patient's recommendation response. Though intuitively similar, this 'recommendation' metric was found to be materially different to satisfaction responses. The difference between THR (NPS 71) and TKR (NPS 49) suggests that no overarching score for a department should be used without an adjustment for case mix. However, the Net Promoter Score does measure a further important dimension to our existing metrics: the patient experience of healthcare delivery.
Collapse
|
98
|
Hamilton DF, Gatherer D, Robson J, Graham N, Rennie N, Maclean JGB, Simpson AHRW. Comparative cervical profiles of adult and under-18 front-row rugby players: implications for playing policy. BMJ Open 2014; 4:e004975. [PMID: 24797427 PMCID: PMC4025467 DOI: 10.1136/bmjopen-2014-004975] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
OBJECTIVE To compare the cervical isometric strength, fatigue endurance and range of motion of adult and under-18 age-grade front-row rugby players to inform the development of a safe age group policy with particular reference to scrummaging. DESIGN Cross-sectional cohort study. SETTING 'Field testing' at Murrayfield stadium. PARTICIPANTS 30 high-performance under-18 players and 22 adult front-row rugby players. OUTCOME MEASURES Isometric neck strength, height, weight and grip strength. RESULTS Youth players demonstrated the same height and grip strength as the adult players; however, the adults were significantly heavier and demonstrated substantially greater isometric strength (p<0.001). Only two of the 'elite' younger players could match the adult mean cervical isometric strength value. In contrast to school age players in general, grip strength was poorly associated with neck strength (r=0.2) in front-row players; instead, player weight (r=0.4) and the number of years' experience of playing in the front row (r=0.5) were the only relevant factors in multivariate modelling of cervical strength (R(2)=0.3). CONCLUSIONS Extreme forces are generated between opposing front rows in the scrum and avoidance of mismatch is important if the risk of injury is to be minimised. Although elite youth front-row rugby players demonstrate the same peripheral strength as their adult counterparts on grip testing, the adults demonstrate significantly greater cervical strength. If older youths and adults are to play together, such findings have to be noted in the development of age group policies with particular reference to the scrum.
Collapse
|
99
|
Simpson AHRW, Hamilton DF, Beard DJ, Barker KL, Wilton T, Hutchison JD, Tuck C, Stoddard A, Macfarlane GJ, Murray GD. Targeted rehabilitation to improve outcome after total knee replacement (TRIO): study protocol for a randomised controlled trial. Trials 2014; 15:44. [PMID: 24484541 PMCID: PMC3911957 DOI: 10.1186/1745-6215-15-44] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 01/16/2014] [Indexed: 11/10/2022] Open
Abstract
Background Approximately 20% of patients are not satisfied with the outcome of total knee replacement, great volumes of which are carried out yearly. Physiotherapy is often provided by the NHS to address dysfunction following knee replacement; however the efficacy of this is unknown. Although clinically it is accepted that therapy is useful, provision of physiotherapy to all patients post-operatively does not enhance outcomes at one year. No study has previously assessed the effect of targeting therapy to individuals struggling to recover in the early post-operative phase. The aim of the TRIO study is to determine whether stratifying care by targeting physiotherapy to those individuals performing poorly following knee replacement is effective in improving the one year outcomes. We are also investigating whether the structure of the physiotherapy provision itself influences outcomes. Methods/Design The study is a multi-centre prospective randomised controlled trial (RCT) of patients undergoing primary total knee replacement, with treatment targeted at those deemed most susceptible to gain from it. Use of the national PROMS programme for pre-operative data collection allows us to screen all patients at initial post-operative clinical review, and recruit only those deemed to be recovering slowly. We aim to recruit 440 patients through various NHS orthopaedic centres who will undergo six weeks of physiotherapy. The intervention will be either ‘intensive’ involving both hospital and home-based functional exercise rehabilitation, or ‘standard of care’ consisting of home exercises. Patients will be randomised to either group using a web-based system. Both groups will receive pre and post-intervention physiotherapy review. Patients will be followed-up to one year post-operation. The primary outcome measure is the Oxford Knee Score. Secondary outcomes are patient satisfaction, functional ability, pain scores and cost-effectiveness. Trial registration Current Controlled Trials ISRCTN23357609. ClinicalTrials.gov NCT01849445.
Collapse
|
100
|
Simpson AHRW, Halliday J, Hamilton DF, Smith M, Mills K. Limb lengthening and peripheral nerve function-factors associated with deterioration of conduction. Acta Orthop 2013; 84:579-84. [PMID: 24171677 PMCID: PMC3851673 DOI: 10.3109/17453674.2013.859418] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND and purpose Limb lengthening is performed for a diverse range of orthopedic problems. A high rate of complications has been reported in these patients, which include motor and sensory loss as a result of nerve damage. We investigated the effect of limb lengthening on peripheral nerve function. PATIENTS AND METHODS 36 patients underwent electrophysiological testing at 3 points: (1) preoperatively, (2) after application of external fixator/corticotomy but before lengthening, and (3) after lengthening. The limb-length discrepancy was due to a congenital etiology (n = 19), a growth disturbance (n = 9), or a traumatic etiology (n = 8). RESULTS 2 of the traumatic etiology patients had significant changes evident on electrophysiological testing preoperatively. They both deteriorated further with lengthening. 7 of the 21 patients studied showed deterioration in nerve function after lengthening, but not postoperatively, indicating that this was due to the lengthening process and not to the surgical procedure. All of these patients had a congenital etiology for their leg-length discrepancy. INTERPRETATION As detailed electrophysiological tests were carried out before surgery, after surgery but before lengthening, and finally after completion of lengthening, it was possible to distinguish between the effects of the operation and the effects of lengthening on nerve function. The results indicate that the etiology, site (femur or tibia), and nerve (common peroneal or tibial) had a bearing on the risk of nerve injury and that these factors had a far greater effect than the total amount of lengthening.
Collapse
|