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Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_19 | Pages 8 - 8
1 Nov 2017
Annan J Murray A
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Simulation in surgical training has become a key component of surgical training curricula, mandated by the GMC, however commercial tools are often expensive. As training budgets become increasingly pressurised, low-cost innovative simulation tools become desirable. We present the results of a low-cost, high-fidelity simulator developed in-house for teaching fluoroscopic guidewire insertion. A guidewire is placed in a 3d-printed plastic bone using simulated fluoroscopy. Custom software enables two inexpensive web cameras and an infra-red led marker to function as an accurate computer navigation system. This enables high quality simulated fluoroscopic images to be generated from the original CT scan from which the bone model is derived and measured guidewire position. Data including time taken, number of simulated radiographs required and final measurements such as tip apex distance (TAD) are collected. The simulator was validated using a DHS model and integrated assessment tool. TAD improved from 16.8mm to 6.6mm (p=0.001, n=9) in inexperienced trainees, and time taken from 4:25s to 2m59s (p=0.011). A control group of experienced surgeons showed no improvement but better starting points in TAD, time taken and number of radiographs. We have also simulated cannulated hip screws, femoral nail entry point and SUFE, but the system has potential for simulating any procedure requiring fluoroscopic guidewire placement e.g. pedicle screws or pelvic fixation. The low cost and 3D-printable nature have enabled multiple copies to be built. The software is open source allowing replication by any interested party. The simulator has been incorporated successfully into a higher orthopaedic surgical training program


The Bone & Joint Journal
Vol. 103-B, Issue 12 | Pages 1802 - 1808
1 Dec 2021
Bruce J Knight R Parsons N Betteridge R Verdon A Brown J Campolier M Achten J Costa ML

Aims

Deep surgical site infection (SSI) is common after lower limb fracture. We compared the diagnosis of deep SSI using alternative methods of data collection and examined the agreement of clinical photography and in-person clinical assessment by the Centers for Disease Control and Prevention (CDC) criteria after lower limb fracture surgery.

Methods

Data from two large, UK-based multicentre randomized controlled major trauma trials investigating SSI and wound healing after surgical repair of open lower limb fractures that could not be primarily closed (UK WOLLF), and surgical incisions for fractures that were primarily closed (UK WHiST), were examined. Trial interventions were standard wound care management and negative pressure wound therapy after initial surgical debridement. Wound outcomes were collected from 30 days to six weeks. We compared the level of agreement between wound photography and clinical assessment of CDC-defined SSI. We are also assessed the level of agreement between blinded independent assessors of the photographs.


The Bone & Joint Journal
Vol. 102-B, Issue 9 | Pages 1229 - 1241
14 Sep 2020
Blom RP Hayat B Al-Dirini RMA Sierevelt I Kerkhoffs GMMJ Goslings JC Jaarsma RL Doornberg JN

Aims

The primary aim of this study was to address the hypothesis that fracture morphology might be more important than posterior malleolar fragment size in rotational type posterior malleolar ankle fractures (PMAFs). The secondary aim was to identify clinically important predictors of outcome for each respective PMAF-type, to challenge the current dogma that surgical decision-making should be based on fragment size.

Methods

This observational prospective cohort study included 70 patients with operatively treated rotational type PMAFs, respectively: 23 Haraguchi Type I (large posterolateral-oblique), 22 Type II (two-part posterolateral and posteromedial), and 25 (avulsion-) Type III. There was no standardized protocol on how to address the PMAFs and CT-imaging was used to classify fracture morphology and quality of postoperative syndesmotic reduction. Quantitative 3D-CT (Q3DCT) was used to assess the quality of fracture reduction, respectively: the proportion of articular involvement; residual intra-articular: gap, step-off, and 3D-displacement; and residual gap and step-off at the fibular notch. These predictors were correlated with the Foot and Ankle Outcome Score (FAOS) at two-years follow-up.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 8 - 8
1 Apr 2013
Hoang-Kim A Goldhahn J Beaton D Macdermid J Ladd A
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Introduction. Lack of standardization of outcome measurement has hampered an evidence-based approach to clinical practice and research. We report on the progress on establishing a minimal set of core domains for outcome measurement in distal radius fracture. Materials and methods. Participants included an expert panel of orthopaedic surgeons, outcome researchers, patients, physiotherapists, industry representatives involved in distal radius research and partners in regulatory affairs. Decisions were made by review of evidence and theory and establishing group consensus. Results. There was consensus that clinical research studies should include a proof of concept outcome that would directly assess the presumed direct benefit of the intervention. We identified a need for additional outcome measures for research including measures that provide more detail on pain and function; or that address supplemental concepts important to that study. Measures of fracture healing/alignment, grip strength, joint motion were recognized as commonly utilized secondary outcomes. Discussion and Conclusion. Our approach provides preliminary steps in establishing core domains that have content relevant to patient goals (i.e. pain and function) and the providers’ treatment goals (i.e. strength, range of motion, function). The panel recommendations provide flexibility in establishing customized data collection for specific indications; but offer some core consistency


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 145 - 145
1 Sep 2012
Tayton E Kalra S Briscoe A Aarvold A Smith J Lanham S Fahmy S Howdle S Shakesheff K Dunlop D Oreffo R
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Background. Impaction bone grafting with milled human allograft is the gold standard for replacing lost bone stock during revision hip surgery. Problems surrounding the use of allograft include cost, availability, disease transmission and stem subsidence (usually due to shear failure of the surrounding allograft). Aims. To investigate various polymers for use as substitute allograft. The ideal graft would be a composite with similar mechanical characteristics as allograft, and with the ability to form de novo bone. Methods. High and low molecular weight (MW) forms of three different polymers (polylactic acid (PLA), poly (lactic-co-glycolic) acid (PLGA) and polycaprolactone (PCL)) were milled, impacted into discs, and then tested in a custom built shear testing rig, and compared to allograft. A second stage of the experiment involved the addition of skeletal stem cells (SSC) to each of the milled polymers, impaction, 8 days incubation, and then tests for cell viability and number, via fluorostaining and biochemical (WST-1, DNA) assays. Results. The shear strengths of both high/ low MW PLA, and high/low MW PLGA were significantly higher than those of milled allograft but high and low MW PCL was poor to impact, and had significantly lower shear strengths. Fluorostaining showed good cell survival on high MW PLA, high MW PCL and both high and low MW PLGA. These findings were confirmed on both DNA and WST-1 assays. Conclusions. High MW PLA as well as high and low MW PLGA performed well both in mechanical testing and cell compatibility studies. These three polymers are good contenders to produce a living composite for use as substitute human allograft in impaction bone grafting


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 100 - 100
1 Sep 2012
Chuter G Ramaskandhan J Siddique M
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Introduction. The standard practice of uncomplicated total ankle replacement (TAR) involves post-operative immobilisation. Periprosthetic fracture is a well-recognised complication following ankle arthroplasty. It occurs predominantly as a stress reaction on the medial tibial metaphysis during the post-operative rehabilitation period. Occasionally it occurs during surgery. We present fractures from a single-centre series of Mobility TARs. Materials and Methods. We have 133 TARs with 3 to 48 months' follow-up. 28 patients were excluded for the following reasons: other major procedure performed concurrently (osteotomy or tendon transfer), custom prosthesis, revision surgery, fusion conversions, or patients involved in a separate RCT (n = 16). We do not routinely immobilise patients post-operatively but allow partial to full weight-bearing as able. Outcome scores were compared to those without fractures. Results. 105 patients were included in the study. Nine (8.6%) patients sustained a periprosthetic fracture with no history of significant trauma. One of these was intra-operative; this was a posterior tibial fracture noticed on post-operative radiographs. The remainder (n = 8) were tibial metaphyseal stress fractures, all occurring within the first three months, most (n = 6) within six weeks. One occurred on the sixth post-op day and was managed in cast. Seven were asymptomatic at diagnosis and managed non-operatively; one was fixed at three months due to radiological medial migration of the talus and one was fixed at seven months due to progression to symptomatic non-union. The remainder united. Between those with and without fractures, there was no significant difference in age (mean 61.4 vs. 62.1, p = 0.387), diagnosis leading to arthroplasty (OA, RA, PTOA), or outcome scores (12 months: 83 vs. 78, p = 0.237). Conclusion. Periprosthetic fracture remains a significant complication of total ankle arthroplasty. However, in our series, they do not lead to increased morbidity or worse outcome scores than patients without fractures and most can be managed non-operatively


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 256 - 256
1 Sep 2012
Weber P Schröder C Utzschneider S Jansson V Müller P
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Introduction. Unicompartmental knee arthroplasty (UKA) in patients with isolated medial osteoarthritis of the knee is nowadays a standard procedure with good results, especially with the minimally-invasive approach. However, the survival rate of the unicompartmental knee prostheses is inferior to that of total knee prostheses. Therefore, further studying of UKA is still necessary. In most mobile bearing designs the femoral component has a spherical surface and therefore its positioning is not crucial. The role of the tibial slope in UKA has not been investigated so far. The manufacturers recommend tibial slopes with values between 10° positive slope and 5° negative slope. Most surgeons try to reconstruct the anatomical slope with a high failure by measuring the slope on x-rays. The aim of this study was to investigate the influence of the tibial slope on the wear rate of a medial UKA. Materials and methods. In vitro wear simulation of medial mobile bearing unicompartmental knee prosthesis with a spherical femoral surface (Univation ®) was performed with a customized four-station servo-hydraulic knee wear simulator (EndoLab GmbH, Thansau, Germany) reproducing exactly the walking cycle as specified in ISO 14243–1:2002(E). The tibial tray was inserted with 2 different medial tibial slopes: 0°, 8° (n=3 for each group). The lateral tibial slope of the space-holder was not changed (0° for every group). We performed a total of 5 million cycles for every different slope, the gravimetric wear rate was determined gravimetrically using an analytical balance every 500 000 cycles according to the ISO 14243–2. Results. The wear rate in the 0° slope group was 3.46±0.59 mg/million cycles, and in the 8° slope group it was 0.99±0.42 mg/million cycles. The difference between the 0° tibial slope group and the 8° tibial slope group was highly significant (p<0.01, alternate t-test). Discussion. An increase of the tibial slope leads to a reduced wear rate in a mobile bearing UKA. Therefore, a higher tibial slope should be recommended for mobile bearing UKA. However, the influence on the ligaments has to be considered as a higher tibial slope leads to an increased strain on the anterior cruciate ligament. This influences needs to be investigated in further studies before a definite optimal range for the tibial slope can be recommended


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 242 - 242
1 Sep 2012
Shoda E Ouchi K Maruyama S Suzuki A Kitada S
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INTRODUCTION. Short femoral nail is the most popular instrumentation for femoral trochanteric fractures. PFNA is in widely use and good results are reported. In these papers, fracture classification and evaluation of surgical results were based on plain X-ray. However, some cases of delayed union, non-union, and blade cut out showed no critical problems in immediate postoperative X-ray. Cause of these complications was not able to solve in X-ray analysis. CT scan provides more information about fracture pattern and position of nail and blade. CT analysis is likely to solve the cause of these complications. MATERIALS & METHODS. 20 cases of 36 femoral trochanteric fractures treated with PFNA-II were evaluated by CT scan (pre and post surgery). Four males and 16 females, and average age at surgery was 80.5 (65–100). Eleven cases were A1 fracture and 9 cases were A2 fracture in AO classification. Nail insertion hole was made by custom made Hollow Reamer. Fracture classification with 3D-CT (Nakano's classification), position of nail insertion hole (relationship between neck or head), and postoperative evaluation with 3D-CT insertion part of nail and blade were investigated. RESULTS. Nakano classified femoral trochanteric fracture into 7 types in 3D-CT. Two subtype in 2 part fracture, 4 subtype in 3 part fracture and 4part fracture. Seven cases were two part fracture, 11 were three part, and 2 were four part in our series. Five cases of 11 in 3 part fracture was considered unstable type. Nail insertion hole of six cases was made posteriory to the connecting line between neck center and head center. Fracture line of greater trochnater in lateral wall opened in 4 cases because of nail insertion. DISCUSSION. Femoral trochanteric fracture was classified by Evans classification or AO classification. However, it is very difficult to classify the fracture by plain X-P. Classification with 3D-CT is very usefull to distinguish which the fracture is stable or unstable. CT analysis will solve the postoperative complications in stable type in X-P classification


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 393 - 393
1 Sep 2012
Zlowodzki M Wijdicks C Armitage B Cole P
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Introduction. Femoral neck fractures are a large clinical and economical problem. One of the most common fixation options for femoral neck fractures are multiple cancellous screws. A previous clinical study has shown the lack of washers to be the single largest predictor of fixation failure in the treatment of femoral neck fractures with cancellous screws. This finding was somewhat surprising as washers do not prevent the screws from backing out and do not provide any increase resistance to varus collapse. Therefore a follow-up biomechanical study was designed to test this observation. The purpose was to evaluate the maximal insertional torque of screws in osteoporotic bone with and without washers. We hypothesized that the lateral cortex of an osteoporotic proximal femur does not provide sufficient counter resistance for the screw heads to obtain maximum torque upon screw insertion in the femoral head and that the use of washers would increase screw purchase by providing a larger rigid surface area and subsequent higher counter resistance thereby allowing a higher maximal screw insertion torque. Methods. We used eight matched pairs of osteoporotic fresh-frozen human cadaveric femurs (age >70 years, all female). Two screws each were inserted in each femur either with or without a washer and maximal insertional torque was measured using a 50 Nm torque transducer. The testing was performed using a customized device which allowed the torque transducer to apply a constant axial force and torque speed to the screws. A paired Student's t-test was used to compare the maximal screw insertional torque of screws with washers versus screws without washers in matched pairs. Results. Fifteen out of 16 times the maximal screw insertional torque was higher when a washer was used. The average maximal torque with a washer was 5.1 Newtonmeter (Nm) compared to 3.1 Nm without a washer (p<0.001). Conclusion. We conclude that the addition of washers increases the maximal insertion torque of cancellous screws in the treatment of osteoporotic femoral neck fractures by providing counter resistance to the screw heads at an otherwise weak lateral cortex. We have demonstrated that the washer prevents the screw heads from penetrating the lateral cortex and provides for an improved purchase of the screws in the femoral head. As a clinical reference value for interpretation of this data, the limit of torque limiting screw drivers used with locking plates is set between 4 and 6 Nm. Therefore the difference in insertion torques likely represents clinically relevant values. Since there is no apparent disadvantage in the use of washers and they are inexpensive and readily available even in less developed countries, we advocate for their routine use until larger clinical studies disprove their efficacy


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 193 - 193
1 Sep 2012
Lipperts M Grimm B Van Asten W Senden R Van Laarhoven S Heyligers I
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Introduction. In orthopaedics, clinical outcome assessment (COA) is still mostly performed by questionnaires which suffer from subjectivity, a ceiling effect and pain dominance. Real life activity monitoring (AM) holds the promise to become the new standard in COA with small light weight and easy to use accelerometers. More and more activities can be identified by algorithms based on accelerometry. The identification of stair climbing for instance is important to assess the participation of patients in normal life after an orthopaedic procedure. In this study we validated a custom made algorithm to distinguish normal gait, ascending and descending stairs on a step by step basis. Methods. A small, lightweight 3D-accelerometer taped to the lateral side of the affected (patients) or non-dominant (healthy subjects) upper leg served as the activity monitor. 13 Subjects (9 patients, 4 healthy) walked a few steps before descending a flight stairs (20 steps with a 180o turn in the middle), walked some steps more, turned around and ascended the same stairs. Templates (up, down and level) were obtained by averaging and stretching the vertical acceleration in the 4 healthy subjects. Classification parameters (low pass (0.4 Hz) horizontal (front-back) acceleration and the Euclidian distance between the vertical acceleration and each template) were obtained for each step. Accuracy is given by the percentage of correctly classified steps. Results. In total the subjects took 537 (41+/-8 mean+/-std) steps, 525 of which were correctly identified as step. 12 Steps were not detected, and 2 steps were incorrectly identified as step. Per subject the accuracy of the classification algorithm ranged from 57% to 97%. In only 2 subjects the accuracy was less than 75%, giving an overall accuracy of 85%. Discussion. In literature algorithms able to identify walking the stairs and normal walking have been reported with an accuracy in the range of 80–95%1,2. Our algorithm falls well within this range, and can be even further improved. The low accuracy in two subjects can be explained by the fact that the sensor was placed more to the front of the leg, which influences the low-pass horizontal acceleration. Using a combination of front-back and left-right acceleration could possibly solve this problem. In the future we are confident to identify also other activities and even distinguish different types of stair climbing (i.e. taking a step with each leg versus only taking steps with the unaffected leg and ‘dragging’ the second leg) and obtain more specific activity profiles to be used in clinical outcome assessment


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 235 - 235
1 Sep 2012
Lipperts M Senden R Van Asten W Heyligers I Grimm B
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Introduction. In orthopaedics, clinical outcome assessment (COA) is mostly performed by questionnaires which suffer from subjectivity, a ceiling effect and pain dominance. Real life activity monitoring (AM) can objectively assess function and becomes now feasible as technology has become smaller, lighter, cheaper and easier to use. In this study we validated a custom made algorithm based on accelerometry using different orthopaedic patients with the aim to use AM in orthopaedic COA. Methods. A small, lightweight 3D-accelerometer taped to the lateral side of the affected upper leg served as the activity monitor. AM algorithms were programmed in Matlab to classify standing, sitting, and walking. For validation a common protocol was used; subjects were asked to perform several tasks for 5 or 10 seconds in a fixed order. An observer noted the starting time of each task using a stopwatch. Accuracy was calculated for the number of bouts per activity as well as total time per activity. 10 Subjects were chosen with different pathologies (e.g. post total knee/hip arthroplasty, osteoarthritis) since the difference in movement dynamics in each pathology poses a challenge to the algorithm. Results. In total the subjects performed 267 activities (99 standing, 80 sitting, 88 walking), 258 of which (99, 73, 87 resp.) were classified correctly by the algorithm, corresponding to a sensitivity of 97%. Sensor misplacement in 1 subject caused all missed instances in sitting, and exclusion of this subject increased sensitivity to 99.9%. 5 Instances of standing were incorrectly added by the algorithm, giving a specificity of 95% for standing. In total 80 sit-stand, and 78 stand-sit transitions were performed. Subjects were standing for 792 seconds, sitting for 764 s, and walking for 905 s. The algorithm found a total duration of 739, 583 and 1056 seconds for those activities respectively, and 83 seconds of lying (misclassification of sitting). Discussion. Sensor placement is an important factor to obtain reliable results. Even so sensitivity and specificity are comparable to values found in literature [85–99%]. The added instances of standing occurred when a subject did not immediately sit after a period of walking. It is doubtful if these instances should be considered false positives. The main difference in duration is also found in sitting, which is caused by the missed instances previously described, in combination with the fact that the duration of transitions are added to the walking period in the algorithm, whereas it is divided over sitting and walking by the observer. This corresponds to a difference of less than one second per transition. The algorithm produces reliable results when challenged with different movement patterns common with orthpaedic pathologies. The device may be used as as AM in objective assessment of clinical outcome after orthopaedic procedures


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 298 - 298
1 Sep 2012
Rouvillain JL Navarre T Labrada Blanco O Daoud W Garron E Cotonea Y
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Introduction. Conservative treatment of Achilles tendon ruptures may lead to re-rupture. Open surgical repair entails a risk of skin necrosis or infection. Several percutaneous techniques have been used, like Tenolig® or Achillon®, but these techniques are costly and may be marred by wound healing problems. Ma and Griffith described a technique for percutaneous repair witch left the suture and the knot under the skin, thus reducing the risk for infection. Material and Methods. From January 2001 to September 2006, we used this percutaneous treatment for 60 acute ruptures of Achille tendon. The repair was made under local anaesthesia, using a single or double absorbable suture. Postoperative care was 3 weeks immobilisation in a cast in equinus position with no weight bearing, followed by another 3 weeks in a cast with the ankle at 90° with progressive weight bearing. Results. Mean follow-up was 19 months. Complications were 2 re-ruptures at 2 and 5 months respectively, 1 infection in a patient who presented with re-rupture after a previous surgical treatment, and 1 Achilles tendonitis. There was no sural nerve lesion. Mean time to return to working activities was 85 days and mean time to return to sports activities was 5 months. The three competitive sportsmen returned to sports at six months, at the same level. Monopodal weight-bearing was possible for all the patients except one. Hopping was not possible in eight cases. Walking on tiptoe was not possible in four cases. A 5° limitation of dorsiflexion of the ankle was observed in four patients. Clinical results were good with no loss in range of motion. The patients’ subjective evaluation was as follows: 18 judged the outcome as very satisfactory, 40 as satisfactory and two as poor. Discussion. The percutaneous suture technique used in this series differs from other methods of surgical repair in being inexpensive. The only specific equipment required is a long needle with an eyelet, sufficiently rigid to transfix the tendon. In this study we had used a custom needle as the prototype of the “Suturach®” (FH Orthopedics, Heimsbrunn, France) needle which we now use. The technique does not require expensive surgical material and above all, does not leave any foreign body externally in contact with the skin (5) which could be a source of local inflammation, or even of cutaneous necrosis (12). This is particularly important for countries with a hot climate where it is not customary to wear closely fitting shoes. The technique used is reliable, reproducible and easily taught. In this series, it was performed by a number of operators with various levels of training. Conclusion. Percutaneous suture of the Achilles tendon appears as a simple, rapid, effective, reproducible and inexpensive technique. It combines the advantages of open surgery with a low risk of re-rupture and those of functional treatment with a low risk of infection


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 84 - 84
1 Sep 2012
Schröder C Utzschneider S Grupp T Fritz B Jansson V
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Introduction. Minimally invasive implanted unicompartmental knee arthroplasty (UKA) leads to excellent functional results. Due to the reduced intraoperative visibility it is difficult to remove extruded bone cement particles, as well as bone particles generated through the sawing. These loose third body particles are frequently found in minimally invasive implanted UKA. The aim of this study was to analyse the influence of bone and cement particles on the wear rate of unicompartmental knee prostheses in vitro. Material & Methods. Fixed- bearing unicompartmental knee prostheses (n = 3; Univation F®, Aesculap, Tuttlingen) were tested with a customized four-station servo-hydraulic knee wear simulator (EndoLab GmbH, Thansau, Germany) reproducing exactly the walking cycle as specified in ISO 14243-1:2002. After 5.0 million cycles crushed cortical bone chips were added to the test fluid for 1.5 million cycles to simulate bone particles, followed by 1.5 million cycles blended with PMMA- particles (concentration of the third-body particles: 5g/l; particle diameter: 0.5- 0.7 mm). Every 500 000 cycles the volumetric wear rate was measured (ISO 14243-2) and the knee kinematics were recorded. For the interpretation of the test results we considered four different phases: breaking in- (during the first 2.0 million cycles), the steady state- (from 2.0 million to 5 million cycles), bone particle- and cement particle phase. Finally, a statistical analysis was carried out to verify the normal distribution (Kolmogorov-Smirnov test), followed by direct comparisons to differentiate the volumetric wear amount between the gliding surfaces (paired Student's t-test, p<0.05). Results. The wear rate was 12.5±0.99 mm. 3. /mio. cycles in the breaking-in phase and decreased during the steady state phase to 4.4±0.91 mm. 3. /mio cycles (not significant, p = 0,3). The bone particles did not have any influence on the wear rate (3.0±1.27 mm. 3. /mio cycles; p = 0,83) compared to the steady state phase. The cement particles, however, lead to a significantly higher wear rate compared to the steady state phase (25.0±16.93 mm. 3. /mio cycles; p<0.05). Discussion. To our knowledge this is the first study demonstrating that free cement debris which can be found after minimally invasive implanted UKA increases significantly the wear- rate. Bone particles generated for instance through sawing during implantation, however, had no influence on the prostheses wear rate. Our Data suggests, that it is extremely important to remove all the extruded cement debris accurately during implantation in order to avoid a higher wear rate which could result in an early loosening of the prostheses


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 263 - 263
1 Sep 2012
Monk A Grammatopoulos G Chen M Gibbons M Beard D Gill H Murray D
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Introduction. Osteoarthritis (OA) of the hip is an important cause of pain and morbidity. The mechanisms and pathogenesis of OA'sdevelopment remain unknown. Minor acetabular dysplasia and subtle variations in proximal femoral morphology are increasingly being recognized as factors that potentially compromise the joint biomechanically and lead to OA. Previous studies have shown that risk of hip OA increased as the femoral head to femoral neck ratio (HNR) decreased. Previous work has described the evolutionary change in inferior femoral neck trabecular density and geometry associated with upright stance, but no study has highlighted the evolutionary change in HNR. The aim of this study was to examine evolutionary evidence that the hominin bipedal stance has lead to alterations in HNR that would predispose humans to hip OA. Methods. A collaboration with The Natural History Museums of London, Oxford and the Department of Zoology, University of Oxford provided specimens from the Devonian, Jurassic, Cretaceous, Miocene, Palaeolithic and Pleistocene periods to modern day. Specimens included amphibious reptiles, dinosaurs, shrews, tupaiae, lemurs, African ground apes, Lucy (A. Afarensis), H. Erectus, H. Neaderthalis and humans. Species were grouped according to gait pattern; HAKF (hip and knee flexed), Arboreal (ability to stand with hip and knee joints extended) and hominin/bi-pedal. Imaging of specimens was performed using a 64 slice CT scanner. Three-dimensional skeletal geometries were segmented using MIMICS software. Anatomical measurements from bony landmarks were performed to describe changes in HNR, in the coronal plane of the different specimens over time using custom software. Measurements of HNR from the specimens were compared with HNR measurements made from AP pelvic radiographs of 119 normal subjects and 210 patients with known hip OA listed for hip arthroplasty. Results. Species from the HAKF group that ambulate via sprawling had the smallest HNR (1.10, SD: 0.09) (p<0.001). Species of the arboreal group (tree dwelling) had the biggest HNR (1.63, SD: 0.15) (p=0.006). The earliest bipedal species (1.41, SD: 0.04) had significantly bigger HNR (p=0.04) in comparison to the normal human subjects (1.33, SD: 0.08). Lower HNR was observed in the OA group (1.3, SD: 0.09). Discussion. The adoption of an upright stance during evolution has created an associated change in the femoral neck bone stock to adapt to the altered loading environment. These data would suggest that the HNR peaked in the Miocene period (10–15 million years ago). The trade-off between mobility and the bony density required to support gait has lead to a decreasing HNR throughout hominid evolution. Evolutionary theory would suggest that modern environmental pressures might pre-dispose future hominid evolution to an increased risk of hip OA


The Bone & Joint Journal
Vol. 100-B, Issue 5 | Pages 634 - 639
1 May 2018
Davda K Heidari N Calder P Goodier D

Aims

The management of a significant bony defect following excision of a diaphyseal atrophic femoral nonunion remains a challenge. We present the outcomes using a combined technique of acute femoral shortening, stabilized with a long retrograde intramedullary nail, accompanied by bifocal osteotomy compression and distraction osteogenesis with a temporary monolateral fixator.

Patients and Methods

Eight men and two women underwent the ‘rail and nail’ technique between 2008 and 2016. Proximal locking of the nail and removal of the external fixator was undertaken once the length of the femur had been restored and prior to full consolidation of the regenerate.


The Bone & Joint Journal
Vol. 100-B, Issue 4 | Pages 646 - 651
1 Apr 2018
Attias N Thabet AM Prabhakar G Dollahite JA Gehlert RJ DeCoster TA

Aims

This study reviews the use of a titanium mesh cage (TMC) as an adjunct to intramedullary nail or plate reconstruction of an extra-articular segmental long bone defect.

Patients and Methods

A total of 17 patients (aged 17 to 61 years) treated for a segmental long bone defect by nail or plate fixation and an adjunctive TMC were included. The bone defects treated were in the tibia (nine), femur (six), radius (one), and humerus (one). The mean length of the segmental bone defect was 8.4 cm (2.2 to 13); the mean length of the titanium mesh cage was 8.3 cm (2.6 to 13). The clinical and radiological records of the patients were analyzed retrospectively.


The Bone & Joint Journal
Vol. 98-B, Issue 4 | Pages 542 - 547
1 Apr 2016
Leonardsson O Rolfson O Rogmark C

Aims

Hemiarthroplasty of the hip is usually carried out through either a direct lateral or posterior approach. The aim of this prospective observational study was to determine any differences in patient-reported outcomes between the two surgical approaches.

Patients and Methods

From the Swedish Hip Arthroplasty Register we identified patients of 70 years and above who were recorded as having had a hemiarthroplasty during 2009. Only patients who had been treated with modern prostheses were included. A questionnaire was posted to those who remained alive one year after surgery. A total of 2118 patients (78% of those available) with a mean age of 85 years (70 to 102) returned the questionnaire.


The Bone & Joint Journal
Vol. 95-B, Issue 9 | Pages 1263 - 1268
1 Sep 2013
Savaridas T Wallace RJ Salter DM Simpson AHRW

Fracture repair occurs by two broad mechanisms: direct healing, and indirect healing with callus formation. The effects of bisphosphonates on fracture repair have been assessed only in models of indirect fracture healing.

A rodent model of rigid compression plate fixation of a standardised tibial osteotomy was used. Ten skeletally mature Sprague–Dawley rats received daily subcutaneous injections of 1 µg/kg ibandronate (IBAN) and ten control rats received saline (control). Three weeks later a tibial osteotomy was rigidly fixed with compression plating. Six weeks later the animals were killed. Fracture repair was assessed with mechanical testing, radiographs and histology.

The mean stress at failure in a four-point bending test was significantly lower in the IBAN group compared with controls (8.69 Nmm-2 (sd 7.63) vs 24.65 Nmm-2 (sd 6.15); p = 0.017). On contact radiographs of the extricated tibiae the mean bone density assessment at the osteotomy site was lower in the IBAN group than in controls (3.7 mmAl (sd 0.75) vs 4.6 mmAl (sd 0.57); p = 0.01). In addition, histological analysis revealed progression to fracture union in the controls but impaired fracture healing in the IBAN group, with predominantly cartilage-like and undifferentiated mesenchymal tissue (p = 0.007).

Bisphosphonate treatment in a therapeutic dose, as used for risk reduction in fragility fractures, had an inhibitory effect on direct fracture healing. We propose that bisphosphonate therapy not be commenced until after the fracture has united if the fracture has been rigidly fixed and is undergoing direct osteonal healing.

Cite this article: Bone Joint J 2013;95-B:1263–8.


The Journal of Bone & Joint Surgery British Volume
Vol. 91-B, Issue 1 | Pages 108 - 112
1 Jan 2009
Chandrasekar CR Grimer RJ Carter SR Tillman RM Abudu A Buckley L

Endoprosthetic replacement of the proximal femur may be required to treat primary bone tumours or destructive metastases either with impending or established pathological fracture. Modular prostheses are available off the shelf and can be adapted to most reconstructive situations for this purpose. We have assessed the clinical and functional outcome of using the METS (Stanmore Implants Worldwide) modular tumour prosthesis to reconstruct the proximal femur in 100 consecutive patients between 2001 and 2006. We compared the results with the published series for patients managed with modular and custom-made endoprosthetic replacements for the same conditions.

There were 52 males and 48 females with a mean age of 56.3 years (16 to 84) and a mean follow-up of 24.6 months (0 to 60). In 65 patients the procedure was undertaken for metastases, in 25 for a primary bone tumour, and in ten for other malignant conditions. A total of 46 patients presented with a pathological fracture, and 19 presented with failed fixation of a previous pathological fracture. The overall patient survival was 63.6% at one year and 23.1% at five years, and was significantly better for patients with a primary bone tumour than for those with metastatic tumour (82.3% vs 53.3%, respectively at one year (p = 0.003)). There were six early dislocations of which five could be treated by closed reduction. No patient needed revision surgery for dislocation. Revision surgery was required by six (6%) patients, five for pain caused by acetabular wear and one for tumour progression. Amputation was needed in four patients for local recurrence or infection.

The estimated five-year implant survival with revision as the endpoint was 90.7%. The mean Toronto Extremity Salvage score was 61% (51% to 95%). The implant survival and complications resulting from the use of the modular system were comparable to the published series of both custom-made and other modular proximal femoral implants.

We conclude that at intermediate follow-up the modular tumour prosthesis for proximal femur replacement provides versatility, a low incidence of implant-related complications and acceptable function for patients with metastatic tumours, pathological fractures and failed fixation of the proximal femur. It also functions as well as a custom-made endoprosthetic replacement.


Bone & Joint Research
Vol. 1, Issue 6 | Pages 104 - 110
1 Jun 2012
Swinteck BJ Phan DL Jani J Owen JR Wayne JS Mounasamy V

Objectives

The use of two implants to manage concomitant ipsilateral femoral shaft and proximal femoral fractures has been indicated, but no studies address the relationship of dynamic hip screw (DHS) side plate screws and the intramedullary nail where failure might occur after union. This study compares different implant configurations in order to investigate bridging the gap between the distal DHS and tip of the intramedullary nail.

Methods

A total of 29 left synthetic femora were tested in three groups: 1) gapped short nail (GSN); 2) unicortical short nail (USN), differing from GSN by the use of two unicortical bridging screws; and 3) bicortical long nail (BLN), with two angled bicortical and one unicortical bridging screws. With these findings, five matched-pairs of cadaveric femora were tested in two groups: 1) unicortical long nail (ULN), with a longer nail than USN and three bridging unicortical screws; and 2) BLN. Specimens were axially loaded to 22.7 kg (50 lb), and internally rotated 90°/sec until failure.