61 results found
Thompson SM, Prinold JAI, Hill AM, et al., 2019, The influence of full-thickness supraspinatus tears on abduction moments: the importance of the central tendon, Shoulder and Elbow, Vol: 11, Pages: 19-25, ISSN: 1758-5740
Background: Detachment of the central tendon of the supraspinatus from its insertion is considered to be crucial to functional deficit. The aim of the present study was to assess the function of the supraspinatus in terms of abduction moments by introducing different tear configurations to assess the functional effect of the central tendon insertion. Methods: Ten fresh frozen shoulders from five cadavers were prepared for testing. A testing protocol was established to measure the abduction moment of the supraspinatus under physiological loading tailored to the anthropometrics of each specimen. Four conditions were tested: intact supraspinatus; complete detachment of portion of the supraspinatus tendon anterior to the main central tendon; detachment of the main central tendon; and detachment of the region of the supraspinatus posterior to the main central tendon. Results: There was a significant and large reduction in abduction moment when the central tendon was sectioned (p < 0.05). A smaller reduction in abduction moment was found when the regions anterior and posterior to the main central tendon were sectioned (p < 0.05). Conclusions: The central tendon is vital in the role of functional arm abduction through force transmission through the intact rotator cuff. Reinsertion of the central tendon in the correct anatomical location is desirable to optimize functional outcome of surgery.
Villatte G, Spurr S, Broden C, et al., 2018, The Eden-Hybbinette procedure is one hundred years old! A historical view of the concept and its evolutions, INTERNATIONAL ORTHOPAEDICS, Vol: 42, Pages: 2491-2495, ISSN: 0341-2695
Villatte G, Muller A-S, Pereira B, et al., 2018, Use of Patient-Specific Instrumentation (PSI) for glenoid component positioning in shoulder arthroplasty. A systematic review and meta-analysis, PLOS ONE, Vol: 13, ISSN: 1932-6203
Kwasnicki RM, Cross GW, Geoghegan L, et al., 2018, A lightweight sensing platform for monitoring sleep quality and posture: a simulated validation study, EUROPEAN JOURNAL OF MEDICAL RESEARCH, Vol: 23, ISSN: 0949-2321
BackgroundThe prevalence of self-reported shoulder pain in the UK has been estimated at 16%. This has been linked with significant sleep disturbance. It is possible that this relationship is bidirectional, with both symptoms capable of causing the other. Within the field of sleep monitoring, there is a requirement for a mobile and unobtrusive device capable of monitoring sleep posture and quality. This study investigates the feasibility of a wearable sleep system (WSS) in accurately detecting sleeping posture and physical activity.MethodsSixteen healthy subjects were recruited and fitted with three wearable inertial sensors on the trunk and forearms. Ten participants were entered into a ‘Posture’ protocol; assuming a series of common sleeping postures in a simulated bedroom. Five participants completed an ‘Activity’ protocol, in which a triphasic simulated sleep was performed including awake, sleep and REM phases. A combined sleep posture and activity protocol was then conducted as a ‘Proof of Concept’ model. Data were used to train a posture detection algorithm, and added to activity to predict sleep phase. Classification accuracy of the WSS was measured during the simulations.ResultsThe WSS was found to have an overall accuracy of 99.5% in detection of four major postures, and 92.5% in the detection of eight minor postures. Prediction of sleep phase using activity measurements was accurate in 97.3% of the simulations. The ability of the system to accurately detect both posture and activity enabled the design of a conceptual layout for a user-friendly tablet application.ConclusionsThe study presents a pervasive wearable sensor platform, which can accurately detect both sleeping posture and activity in non-specialised environments. The extent and accuracy of sleep metrics available advances the current state-of-the-art technology. This has potential diagnostic implications in musculoskeletal pathology and with the addition of aler
Junaid S, Gregory T, Fetherston S, et al., 2018, Cadaveric study validating in vitro monitoring techniques to measure the failure mechanism of glenoid implants against clinical CT, Journal of Orthopaedic Research, ISSN: 0736-0266
Definite glenoid implant loosening is identifiable on radiographs, however, identifying early loosening still eludes clinicians. Methods to monitor glenoid loosening in vitro have not been validated to clinical imaging. This study investigates the correlation between in vitro measures and CT images. Ten cadaveric scapulae were implanted with a pegged glenoid implant and fatigue tested to failure. Each scapulae were cyclically loaded superiorly and CT scanned every 20,000 cycles until failure to monitor progressive radiolucent lines. Superior and inferior rim displacements were also measured. A finite element (FE) model of one scapula was used to analyze the interfacial stresses at the implant/cement and cement/bone interfaces. All ten implants failed inferiorly at the implant-cement interface, two also failed at the cement-bone interface inferiorly, and three showed superior failure. Failure occurred at of 80,966 ± 53,729 (mean ± SD) cycles. CT scans confirmed failure of the fixation, and in most cases, was observed either before or with visual failure. Significant correlations were found between inferior rim displacement, vertical head displacement and failure of the glenoid implant. The FE model showed peak tensile stresses inferiorly and high compressive stresses superiorly, corroborating experimental findings. In vitro monitoring methods correlated to failure progression in clinical CT images possibly indicating its capacity to detect loosening earlier for earlier clinical intervention if needed. Its use in detecting failure non-destructively for implant development and testing is also valuable. The study highlights failure at the implant-cement interface and early signs of failure are identifiable in CT images. © 2018 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. J Orthop Res 9999:XX-XX, 2018.
Junaid S, Sanghavi S, Anglin C, et al., 2017, Treatment of the Fixation Surface Improves Glenoid Prosthesis Longevity in vitro., Journal of Biomechanics, Vol: 61, Pages: 81-87, ISSN: 0021-9290
Many commercial cemented glenoid components claim superior fixation designs and increased survivability. However, both research and clinical studies have shown conflicting results and it is unclear whether these design variations do improve loosening rates. Part of the difficulty in investigating fixation failure is the inability to directly observe the fixation interface, a problem addressed in this study by using a novel experimental set-up. Cyclic loading-displacement tests were carried out on 60 custom-made glenoid prostheses implanted into a bone substitute. Design parameters investigated included treatment of the fixation surface of the component resulting in different levels of back-surface roughness, flat-back versus curved-back, keel versus peg and more versus less conforming implants. Visually-observed failure and ASTM-recommended rim-displacements were recorded throughout testing to investigate fixation failure and if rim displacement is an appropriate measure of loosening. Roughening the implant back (Ra>3µm) improved resistance to failure (P<0.005) by an order of magnitude with the rough and smooth groups failing at 8712±5584 cycles (mean±SD) and 1080±1197 cycles, respectively. All other design parameters had no statistically significant effect on the number of cycles to failure. All implants failed inferiorly and 95% (57/60) at the implant/cement interface. Rim-displacement correlated with visually observed failure. The most important effect was that of roughening the implant, which strengthened the polyethylene-cement interface. Rim-displacement can be used as an indicator of fixation failure, but the sensitivity was insufficient to capture subtle effects. LEVEL OF EVIDENCE: Basic Science Study, Biomechanical Analysis.
Background: Short stem humeral replacements achieve fixation by anchoring to the metaphyseal trabecular bone. Fixing the implant in high density bone can provide strong fixation and reduce the risk of loosening. However, there is a lack of data mapping the bone density distribution in the proximal humerus. The aim of the study was to investigate the bone density in proximal humerus. Methods: Eight CT scans of healthy cadaveric humeri were used to map bone density distribution in the humeral head. The proximal humeral head was divided into twelve slices parallel to the humeral anatomical neck. Each slice was then divided into four concentric circles. The slices below the anatomical neck, where short stem implants have their fixation features, were further divided into radial sectors. The average bone density for each of these regions was calculated and regions of interest were compared using a repeated measures ANOVA with significance set at p<0.05.Results: Average apparent bone density was found to decrease from proximal to distal regions with the majority of higher bone density proximal to the anatomical neck of the humerus (p<0.05). Below the anatomical neck, bone density increases from central to peripheral regions where cortical bone eventually occupies the space (p<0.05). In distal slices below the anatomical neck, a higher bone density distribution in the medial calcar region was also observed.Conclusion: This study indicates that it is advantageous with respect to implant fixation to preserve some bone above the anatomical neck and epiphyseal plate, and to use the denser bone at the periphery.
Blackwood C, Dixon J, Reilly P, et al., 2017, Legal and psychological considerations for obtaining informed consent for reverse total shoulder arthroplasty., Shoulder Elbow, Vol: 9, Pages: 15-22, ISSN: 1758-5732
This paper seeks to outline recent legal developments and requirements pertinent to obtaining informed consent. We argue that this is of particular relevance to patients considering a reverse total shoulder arthroplasty, due to the high complication rate associated with this procedure. By examining the cognitive processes involved in decision-making, and other clinician-related factors such as delivery of information, gender bias and conflict of interest, we explore some of the barriers that can undermine the processes of shared decision-making and obtaining genuine informed consent. We argue that these issues highlight the importance for surgeons in understanding the cognitive processes and other influential factors involved in patients' comprehension and decision-making. We recommend, based on strong evidence, that decision aids could prove useful in overcoming such challenges and could provide one way of mitigating the ethical, professional and legal consequences of failing to obtain proper informed consent. They are not widely used in orthopaedics at present, although it would be in the interests of both the surgeon and patient for such measures to be explored.
Amirthanayagam TD, Amis AA, Reilly P, et al., 2016, Rotator cuff-sparing approaches for glenohumeral joint access: an anatomic feasibility study, Journal of Shoulder and Elbow Surgery, Vol: 26, Pages: 512-520, ISSN: 1058-2746
BackgroundThe deltopectoral approach for total shoulder arthroplasty can result in subscapularis dysfunction. In addition, glenoid wear is more prevalent posteriorly, a region difficult to access with this approach. We propose a posterior approach for access in total shoulder arthroplasty that uses the internervous interval between the infraspinatus and teres minor. This study compares this internervous posterior approach with other rotator cuff–sparing techniques, namely, the subscapularis-splitting and rotator interval approaches.MethodsThe 3 approaches were performed on 12 fresh frozen cadavers. The degree of circumferential access to the glenohumeral joint, the force exerted on the rotator cuff, the proximity of neurovascular structures, and the depth of the incisions were measured, and digital photographs of the approaches in different arm positions were analyzed.ResultsThe posterior approach permits direct linear access to 60% of the humeral and 59% of the glenoid joint circumference compared with 39% and 42% for the subscapularis-splitting approach and 37% and 28% for the rotator interval approach. The mean force of retraction on the rotator cuff was 2.76 (standard deviation [SD], 1.10) N with the posterior approach, 2.72 (SD, 1.22) N with the rotator interval, and 4.75 (SD, 2.56) N with the subscapularis-splitting approach. From the digital photographs and depth measurements, the estimated volumetric access available for instrumentation during surgery was comparable for the 3 approaches.ConclusionThe internervous posterior approach provides greater access to the shoulder joint while minimizing damage to the rotator cuff.
Sukjamsri, Amis, Hansen UN, 2015, Digital volume correlation and micro-CT: An in-vitro technique for measuring full-field interface micromotion around polyethylene implants, Journal of Biomechanics, ISSN: 1873-2380
Shah M, Gburcik V, Reilly P, et al., 2015, LOCAL ORIGINS IMPART CONSERVED BONE TYPE-RELATED DIFFERENCES IN HUMAN OSTEOBLAST BEHAVIOUR, EUROPEAN CELLS & MATERIALS, Vol: 29, Pages: 155-176, ISSN: 1473-2262
Amirthanayagam TD, Emery RJH, 2014, Primum non nocere: risk assessment for new surgical procedures, JOURNAL OF SHOULDER AND ELBOW SURGERY, Vol: 23, Pages: 1417-1418, ISSN: 1058-2746
Amadi HO, Emery RJ, Wallace A, et al., 2014, Specificity of clinical examinations for testing glenohumeral ligament integrity: a computational study, COMPUTER METHODS IN BIOMECHANICS AND BIOMEDICAL ENGINEERING, Vol: 17, Pages: 933-943, ISSN: 1025-5842
Bayona S, Akhtar K, Gupte C, et al., 2014, Assessing Performance in Shoulder Arthroscopy: The Imperial Global Arthroscopy Rating Scale (IGARS), JOURNAL OF BONE AND JOINT SURGERY-AMERICAN VOLUME, Vol: 96A, ISSN: 0021-9355
Gregory T, Hansen U, Khanna M, et al., 2014, A CT scan protocol for the detection of radiographic loosening of the glenoid component after total shoulder arthroplasty, ACTA ORTHOPAEDICA, Vol: 85, Pages: 91-96, ISSN: 1745-3674
Gregory TM, Sankey A, Augereau B, et al., 2013, Accuracy of Glenoid Component Placement in Total Shoulder Arthroplasty and Its Effect on Clinical and Radiological Outcome in a Retrospective, Longitudinal, Monocentric Open Study, PLOS ONE, Vol: 8, ISSN: 1932-6203
Gregory T, Hansen U, Emery R, et al., 2012, Total shoulder arthroplasty does not correct the orientation of the eroded glenoid, ACTA ORTHOPAEDICA, Vol: 83, Pages: 529-535, ISSN: 1745-3674
Thompson SM, Reilly P, Emery RJH, et al., 2012, A comparison of the degree of retraction of full-thickness supraspinatus tears with the Goutallier grading system, JOURNAL OF SHOULDER AND ELBOW SURGERY, Vol: 21, Pages: 749-753, ISSN: 1058-2746
Amadi HO, Fogg QA, Ugbolue UC, et al., 2012, Reliability of a set of protractors for direct anatomical measurements around the glenoid and humeral head rims, JOURNAL OF ANATOMY, Vol: 220, Pages: 525-528, ISSN: 0021-8782
Amadi HO, Bull AMJ, Emery RJH, 2012, Development and validation of a model for quantifying glenohumeral ligament strains during function, PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART H-JOURNAL OF ENGINEERING IN MEDICINE, Vol: 226, Pages: 461-468, ISSN: 0954-4119
Baring TKA, Cashman PPM, Reilly P, et al., 2011, Rotator cuff repair failure in vivo: a radiostereometric measurement study, JOURNAL OF SHOULDER AND ELBOW SURGERY, Vol: 20, Pages: 1194-1199, ISSN: 1058-2746
Majed A, Macleod I, Bull AMJ, et al., 2011, Proximal humeral fracture classification systems revisited, JOURNAL OF SHOULDER AND ELBOW SURGERY, Vol: 20, Pages: 1125-1132, ISSN: 1058-2746
Thompson SM, Reilly P, Emery RJ, et al., 2011, An anatomical description of the pennation angles and central tendon angle of the supraspinatus both in its normal configuration and with full thickness tears, JOURNAL OF SHOULDER AND ELBOW SURGERY, Vol: 20, Pages: 899-903, ISSN: 1058-2746
Cashman PMM, Baring T, Reilly P, et al., 2010, Measurement of migration of soft tissue by modified Roentgen stereophotogrammetric analysis (RSA): validation of a new technique to monitor rotator cuff tears., J Med Eng Technol, Vol: 34, Pages: 159-165
The purpose of this study was to develop a technique to use Roentgen stereophotogrammetric analysis (RSA) to measure migration of soft-tissue structures after rotator cuff repair. RSA stereo films were obtained; images were analysed using a semi-automatic software program allowing 3D viewing of results. RSA imaging experiments were performed to validate the technique, using a glass phantom with implanted RSA beads and an animal model with steel sutures as RSA markers which were moved known distances. Repeated measurements allowed assessment of inter- and intra-observer variability at a maximum of 1.06 mm. RSA analysis of the phantom showed a variation up to 0.22 mm for static and 0.28 mm for dynamic studies. The ovine tissue specimen demonstrated that using steel sutures as RSA markers in soft tissue is feasible, although less accurate than when measuring bone motion. This novel application of RSA to measure soft tissue migration is practicable and can be extended to in vivo studies.
Junaid S, Gupta S, Sanghavi S, et al., 2010, Failure mechanism of the all-polyethylene glenoid implant, JOURNAL OF BIOMECHANICS, Vol: 43, Pages: 714-719, ISSN: 0021-9290
Gregory T, Hansen U, Taillieu F, et al., 2009, Glenoid Loosening after Total Shoulder Arthroplasty: An In Vitro CT-Scan Study, JOURNAL OF ORTHOPAEDIC RESEARCH, Vol: 27, Pages: 1589-1595, ISSN: 0736-0266
Amadi HO, Majed A, Emery RJH, et al., 2009, A humeral coordinate system for in vivo 3-D kinematics of the Glenohumeral joint, Journal of Musculoskeletal Research (JMR), Vol: 12, Pages: 169-174
The aim of this study was to define axes from clearly identifiable landmarks on the proximal aspect of the humerus and to compare these for reasonable best alternatives to the use of the humeral canal and elbow epicondylar axes to define a humeral coordinate frame (HCF). The elbow epicondylar axis (EC) and six different humeral canal axes (HC) based on varying lengths of humerus were quantified from 21 computed tomography (CT) scans of humeri. Six additional axes were defined using the proximal humerus only. These included a line from the center of a sphere fit on the humeral head to the 3D surface area centroid of the greater tubercle region, (GT). The inclinations of these axes relative to EC were calculated. GT was found to be the most closely aligned to EC (13.4° ± 6.8°). The inclinations of the other axes ranged from 36.3° to 86.8°. The HC axis orientation was found to be insensitive to humeral shaft lengths (variability, within average: 0.6°). This was chosen as one of two axes for the HCF. It was also the most inter-subject related axis to EC with inclination standard deviation of ±1.8°. EC was therefore predicted from this such that if the superior axis [1 0 0] of an image scan is maintained and the humerus rotated to make its quantified HC align superiorly in the direction [0.98 0.01 0.01], then its EC axis lies laterally in the direction [0 0 1]. This study demonstrates that it is possible with confidence to apply an orthogonal coordinate frame to the humerus based on proximal imaging data only
Brassart N, Sanghavi S, Hansen UN, et al., 2008, Loss of rotator cuff tendon-to-bone interface pressure after reattachment using a suture anchor, JOURNAL OF SHOULDER AND ELBOW SURGERY, Vol: 17, Pages: 784-789, ISSN: 1058-2746
Leong JJH, Leff DR, Das A, et al., 2008, Validation of orthopaedic bench models for trauma surgery., J Bone Joint Surg Br, Vol: 90, Pages: 958-965
The aim of this study was to validate the use of three models of fracture fixation in the assessment of technical skills. We recruited 21 subjects (six experts, seven intermediates, and eight novices) to perform three procedures: application of a dynamic compression plate on a cadaver porcine model, insertion of an unreamed tibial intramedullary nail, and application of a forearm external fixator, both on synthetic bone models. The primary outcome measures were the Objective Structural Assessment of technical skills global rating scale on video recordings of the procedures which were scored by two independent expert observers, and the hand movements of the surgeons which were analysed using the Imperial College Surgical Assessment Device. The video scores were significantly different for the three groups in all three procedures (p < 0.05), with excellent inter-rater reliability (alpha = 0.88). The novice and intermediate groups specifically were significantly different in their performance with dynamic compression plate and intramedullary nails (p < 0.05). Movement analysis distinguished between the three groups in the dynamic compression plate model, but a ceiling effect was demonstrated in the intramedullary nail and external fixator procedures, where intermediates and experts performed to comparable standards (p > 0.6). A total of 85% (18 of 21) of the subjects found the dynamic compression model and 57% (12 of 21) found all the models acceptable tools of assessment. This study has validated a low-cost, high-fidelity porcine dynamic compression plate model using video rating scores for skills assessment and movement analysis. It has also demonstrated that Synbone models for the application of and intramedullary nail and an external fixator are less sensitive and should be improved for further assessment of surgical skills in trauma. The availability of valid objective tools of assessment of surgical skills allows further studies into improving methods of
Hopkins AR, Hansen UN, Bull AM, et al., 2008, Fixation of the reversed shoulder prosthesis, J Shoulder and Elbow Surgery, 2008
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.