What is an antalgic (painful) gait? Let the sensors have their say.

Falsehood flies, and the truth comes limping after it, so that when men come to be undeceived, it is too late; the jest is over, and the tale hath had his effect.

Jonathan Swift

One of the things we are taught as medical students and doctors is how to recognise various types of gait. This is an imperfect art, particularly for the less observant among us! I remember telling someone that his painful, slow gait was due to his hip arthritis only to see that after successful hip surgery his gait was still just as slow. It turned out that he also had early Parkinson’s disease, and I had missed the early signs of his neurological condition. And if you think you are immune to such lapses of judgement, perhaps you – like me – were fooled by Virgil’s limp in the film ‘Usual Suspects‘ (one of my favourite cinematic endings).

One of the most basic gaits to recognise is someone walking with a single painful hip joint. This is commonly called the ‘antalgic’ gait, and is characterised by someone spending less time putting their weight on the painful leg compared to the other leg.

When surgeons replace hip joints they hope to relieve pain – but they also need to restore a normal gait pattern. Although pain relief happens quickly in most patients, restoration of normal function is more gradual. The best way to study this scientifically is to apply movement sensors to the limbs – accelerometers or more sophisticated triple component inertial movement sensors (IMUs). A 1999 paper by Aminian et al examined this question in a group of patients who had hip surgery for arthritis in a single hip. It turned out that simply measuring gait speed didn’t show the improvements as clearly as the ‘assymetry of double stance’ time. This is the difference between the time you spend on the bad leg vs. the good leg – i.e a scientific measure of the ‘antalgic gait’.

Using sensors to detect improvements in gait after hip replacement
Sensor detection of changes in assymetric (antalgic) gait after hip replacement surgery

In the top left (pre-op) picture you can see a big spread from the identical line (diagonal) – and then as we move to the bottom right (9 months post-op) you can see that the difference between double-stance time on either leg has narrowed except in one patient (circled in the image below).

Sensor detects Gait in Hip Osteoarthritis after surgery
Sensor detection of changes in assymetric (antalgic) gait after hip replacement surgery: spot the one exception!

Now, as it happens, this poor chap still had pain in his hip. I guess you could have found that out a lot easier just by asking him, but the point is that we’ve found that out through a very objective test. Looking at the trace from the motion sensors, an analyst miles away with no video footage could ‘diagnose’ that he still had an antalgic gait. The same sort of analytics can pick out differences that are just not obvious even to the practised eye.

This is just a simple example taken from what is a rapidly expanding area of the scientific literature – how to accurately measure and define human movement. In this case, the use of movement sensors provided objective evidence of improvements we could have discerned by observing the patient’s gait or by asking them to complete a questionnaire. However, movement analysis can be used to perform much more complex assessments that should help the therapist understand why our patients haven’t quite returned to full function at work or at home. Physiotherapists, sports scientists and experts in biomechanics/computer analytics are leading the way. Watch this space!

Reference: Arminian K et al Med Biol Eng Comput 1999 37 686-691

What is a disease flare in RA? A medical student’s perspective

Introduction: This guest article was written by Anca Smyth, who is currently a fourth year medical student at Queen’s University Belfast. She wrote an essay during her ‘special study component’ three week attachment in Altnagelvin hospital and later submitted it to the Irish Society for Rheumatology. Anca not only won the prestigious Bernard Connor Prize at the 2016 conference, but she was invited to present her paper to the Society. So congratulations to Anca and best wishes for the future! – Philip Gardiner

“When it comes to our health most of us are guilty of thinking that we are invincible. Imagine waking up one morning with excruciating pain, having stiff, swollen joints and weakness which markedly interfere with your ability to carry out the normal activities of daily living. To a rheumatoid arthritis (RA) sufferer such debilitating symptoms may constitute ‘a significant disease flare’, an episodic exacerbation of this chronic, symmetrical, small joint inflammatory condition. Or does it?

Unlike the ACR/EULAR classification criteria for RA [1] which is based on objective measurements of serological parameters, acute phase reactants, numbers and sites of swollen or tender joints and symptom duration, there has been no standard definition of what constitutes a RA flare or how it can be objectively assessed and classified according to severity. Apart from measuring the efficacy and safety of novel pharmacological agents used in the treatment of RA by means of randomised controlled clinical trials, a valid definition and classification of a flare would prove to be an invaluable tool in guiding clinical care and monitoring disease outcome.

When a patient is experiencing a flare, a significant increase in the disease activity so that it requires a change of treatment [2], there is often discrepancy in the interpretation of the severity of signs and symptoms between the doctor and the patient [3]. This may lead to inappropriate treatment, patient dissatisfaction and non-adherence to therapeutic interventions [4, 5]. Such discordance is due to the heterogeneous nature of the patient experience during this acute episode, which not only affects objectively measured clinical parameters but also generates self-reported symptoms such as pain, weakness, sleeplessness or fatigue [6, 7]. From the patient’s perspective the experience of a flare is also about functional impairment, disability and social participation [8, 9] which interfere with the patient’s quality of life and psychological well-being.

There is also variation between RA sufferers regarding what constitutes a significant disease flare. Reasons for this include the fact that patients report the severity of a flare according to their baseline disease activity and previous experiences with the disease [10], thus what seems a severe flare to an early RA patient may be classified as a normal fluctuation of disease activity by someone who has been living with this disease for an extended period of time. Additional factors in defining a significant flare include the level of a patient’s tolerance to worsening of signs and symptoms, health beliefs and coping skills [11, 12].

Current methods of assessing RA patients include measuring the disease activity in 28 joints using the DAS28 score and evaluating physical disability by means of a Health Assessment Questionnaire (HAQ28) and patient’s global health status by employing a 10cm Visual Analogue Scale (VAS).  However, none of these approaches are without flaws. Two of the main determinants of the patient’s global health are pain and fatigue [13], subjective symptoms which cannot be measured accurately and which are influenced by many factors including mental health status and co-morbidities [14]. Considering the ACR/EULAR disease remission criteria of a score of 1 or less on the patient’s global assessment scale of 0-10 such targets may be difficult to achieve accounting for the fact that many RA patients suffer from depression [15] or chronic pain syndrome [16].

The HAQ tool, limited by its ‘ceiling effect’ due to lack of adequate sensitivity in detecting a worsening of disability towards its upper limits or assessing lower limb function [17] does not accurately evaluate the severity of a RA flare. The DAS 28 score, a weighted composite of the number of swollen joints, level of the inflammatory marker ESR (erythrocyte sedimentation rate) and patient global assessment score is currently employed in clinical practice to classify disease activity, guide therapeutic treatment and function as an outcome measure in the treat-to-target approach [18]. Limitations of this approach include a misleadingly low DAS28 score if the flare predominantly affects the patient’s feet, which are not included in the DAS28 joint count, or if it is concentrated on a single joint, causing debilitating pain and rendering the patient unable to work. Conversely, a high DAS28 score based on a large number of swollen joints in the absence of pain or elevated ESR may initiate an unnecessary escalation in therapeutic treatment [19]. Some studies have used the inverse of the improvement criteria based on the DAS28 score to assess the severity of a flare but such a correlation seems inappropriate [20].

Given the complexity of patient experiences and heterogeneity of assessment tools that affect the interpretation of a significant disease flare, there is no ‘one size fits all’ approach to monitoring a flare. In an era of demedicalisation, there is an emphasis on treating the individual in the community, with medical care providers offering evidence based patient education and counselling regarding management of flares or side-effects of medication in the form of leaflets, telephone consultation with various members of the multi-disciplinary team or telecare services for people to report and be advised on their flares [21]. Such a model of care not only promotes self-efficacy and helps achieve an internal locus of control but it also increases accessibility and reduces travelling time for patients in the rural communities.

Since RA is a chronic condition, the patient may be the expert in monitoring their condition and self-management of a flare by means of non-pharmacological (such as exercise, bed rests, applying ice or heat packs or via complementary and alternative therapies) or pharmacological interventions (by increasing the dose of glucocorticoids, analgesics or non steroidal anti-inflammatory medication alongside a fixed-dose of disease modifying anti-rheumatic drugs) seems to be the approach employed by most RA sufferers [22]. There are times, however, when self-management of a flare is ineffective and the patient decides to seek medical help. Although the threshold at which such a decision is made is unknown, the doctor must adopt a holistic approach in assessing the patient and based on shared-decision making determine an appropriate change in treatment.

In conclusion, the concept of a significant disease flare in RA is complex, non-standardised and its interpretation depends on interplay between a patient’s physical and psychological parameters, previous disease experience and health beliefs. Monitoring of this acute episode should occur in the community, with health professionals providing ongoing patient education and counselling and facilitating timely review by the clinician when the patient seeks medical help.”


[1]. Aletaha D, Neogi T, Silman AJ, Funovits J, Felson DT, Bingham CO, Birnbaum NS, Burnester GR et al. 2010 Rheumatoid Arthritis classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative initiative. Arthritis and Rheumatism 2010; 62(9): 2569-2581.

[2]. Alten R, Pohl C, Choy EH, Christensen R, Furst DE, Hewlett SE, Leong A, May JE, Sanderson TC, Strand V, Woodworth TG and Bingham CO. Developing a Construct to Evaluate Flares in Rheumatoid Arthritis: A Conceptual Report of the OMERACT RA Flare Definition Working Group

[3]. Studenic P, Radner H, Smolen JS and Aletaha D. Discrepancies Between Patients and Physicians in Their Perceptions of Rheumatoid Arthritis Disease Activity. Arthritis and Rheumatism 2012; 64(9): 2814-2823.

[4]. Van den Bemt BJF, van den Hoogen FHJ, Benraad B, Hekster YA, van Riel PLC, van Lankveld W. Adherence Rates and Associations with Nonadherence in Patients with Rheumatoid Arthritis Using Disease Modifying Antirheumatic Drugs. The journal of Rheumatology 2009; 36: 2164-2170.

[5]. Matteo MR. Variations in patients’ adherence to medical recommendations: a quantitative review of 50 years of research. Medical Care 2004; 42: 200-209.

[6]. van Tuyl LHD and Boers M. Patient’s Global Assessment of Disease Activity: What Are We Measuring? Arthritis and Rheumatism 2012; 64(9): 2811–2813.

[7]. Kalyoncu U, Dougados M, Daures JP, Gossec L. Reporting of patient-reported outcomes in recent trials in rheumatoid arthritis: a systematic literature review. Annals of the Rheumatic Diseases 2009; 68: 183–190.

[8]. Benka J, Nagyova I, Rosenberger J, Marcejova Z, Lazurova I, van der Klink JL, Groothoff JW and van DijkJP. Social participation in early and established rheumatoid arthritis patients. Disability and Rehabilitation 2015; 19: 1-8.
[9]. Sverker A, Ostlund G, Thyberg I, Valtersson E and Bjork M. Dilemmas of participation in everyday life in early rheumatoid arthritis: a qualitative interview study. Disability and Rehabilitation 2015; 37(14): 1251-1259.
[10]. Seror R, Tubach F, Baron G, Guillemin F, Ravaud P. Measure of function in rheumatoid arthritis: individualised or classical scales? Annals of the Rheumatic Diseases. 2010; 69(1): 97–101.

[11]. Rohekar G and Pope J. Test-Retest Reliability of Patient Global Assessment and Physician Global Assessment in Rheumatoid Arthritis. The Journal of Rheumatology 2015; 36(10): 2178-2182.

[12]. Sanderson TC, Hewlett SE, Flurey C, Dures E, Richards P and Kirwan JR. The impact triad (severity, importance, self-management) as a method of enhancing measurement of personal life impact of rheumatoid diseases. The Journal of Rheumatology 2011; 38: 191-194.

[13]. Bartlett SJ, Bykerk VP, Cooksey R, Choy EH, Alten R, Christensen R, Furst DE et al.  Feasibility and Domain Validation of Rheumatoid Arthritis Flare Core Domain Set: Report of the OMERACT 2014 RA Flare Group Plenary. The Journal of Rheumatology 2015; 42(11): 2185-2189.

[14]. Barton JL, Imboden J, Graf J, Glidden D, Yelin EH and Shillinger D. Patient-Physician Discordance in Assessments of Global Disease Severity in Rheumatoid Arthritis. Arthritis Care and Research 2010; 62(6): 857–864.

[15]. Khan NA, Spencer HJ, Abda E, Aggarwal A, Alten R and Ancuta C. Determinants of discordance in patients’ and physicians’ rating of rheumatoid arthritis disease activity. Arthritis Care Research 2012; 64: 206–14.

[16]. Wolfe F, Michaud K. Severe rheumatoid arthritis (RA), worse outcomes, comorbid illness, and sociodemographic disadvantage characterize RA patients with fibromyalgia. J Rheumatol 2004; 31: 695–700.

[17]. Gardiner PV, Sykes HR, Hassey GA and Walker DJ. An evaluation of the health assessment questionnaire in long term longitudinal follow-up of disability in Rheumatoid Arthritis. British Journal of Rheumatology 1993; 32: 724-728.
[18]. Ward MM, Guthrie LC and Alba MI. Clinically important changes in individual and composite measures of rheumatoid arthritis activity: thresholds applicable in clinical trials. Annals of the Rheumatic Diseases 2013; 1: 205079.
[19]. Pincus T, Yazici Y and Sokka T. Quantitative measures of rheumatic diseases for clinical research versus standard clinical care: differences, advances and limitations. Best Practice and Research Clinical Rheumatology 2007; 21(4): 601-628.

[20]. Leeb BF, Sautner J, Leeb BA, Fassl C, Rintelen B. Lack of agreement between patients’ and physicians’ perspectives of rheumatoid arthritis disease activity changes. Scandinavian Journal of Rheumatology 2006; 35: 441-446.

[21]. National Institute for Health and Care Excellence. Commissioning for people with rheumatoid arthritis. NICE commissioning guides [CMG51], 2013.

[22]. Hewlett S, Sanderson T, May J, Alten R, Bingham CO, Cross M, March L, Pohl C, Woodworth T and Bartlett SJ. ‘I’m hurting, I want to kill myself’: rheumatoid arthritis flare is more than a joint count- an international patient perspective on flare where medical help is sought. Rheumatology 2012; 51:69-76.

Going Mobile: Measuring Physical Activity in Arthritis Research

physexerciseIn this article I’m going to give a brief and mostly non-technical review of three recent research trials that seem to confirm that measured physical activity is now being recognised to be an important outcome measure in patients with arthritis and Ankylosing Spondylitis. The wearable technology to make these measurements possible is now available and their scientific validation has been established, particularly in the field of sports science. In sports science parlance ‘physical activity’ is defined precisely in terms of energy expenditure so that activity levels can be compared across the population. This outcome relates more to the duration and intensity of exercise carried out rather than the specifics of movement that might be impaired by arthritis. The focus here is on the impact of exercise on fitness and health rather than on flexibility and mobility.

Hernandez-Hernandez studied a group of 50 RA patients compared to 50 matched healthy controls using a questionnaire of physical activity called the IPAQ and a tri-axial RT6 accelerometer. The authors stated that they wished to study the correlation between disease activity and physical activity. Those in the study wore the accelerometer device continuously for 5 days and their activity was broken down into light, moderate and vigorous activity using standard cut points. ‘MVPA’ was defined as the amount of time spent in moderate or vigorous physical activity. Disease activity was monitored using the DAS28 and disability assessed using the HAQ. They also recorded fatigue using the FACIT questionnaire and quality of life using the standard SF-36 questionnaire. Results: Although there was a weak correlation with the IPAQ, the self-reported questionnaire did not closely match the accelerometer data. The authors found that accelerometry was able to capture physical activity accurately & that recorded levels of moderate and vigorous physical activity (MVPA) in RA patients was significantly lower than that of healthy controls. The MVPA correlated with the HAQ but not with disease activity. Thirty of the RA patients had a second assessment carried out 6 months after the initial assessment. In this subset they found that a significant change in DAS28 (>1.2) correlated negatively with a change in MVPA.

  • This is possibly the first paper to show a convincing negative correlation between DAS28 and monitored physical activity in the patient’s natural setting.
  • This is also one of the first papers to use the IPAQ in RA patients and to demonstrate a difference in physical activity between RA patients and controls. At the moment it looks as if studies should use both a physical activity questionnaire and a tool to measure activity. Even though 5 days of activity were measured, this is still only a snapshot in time for a patient with RA.


Swinnen et al studied 40 patients with Ankylosing Spondylitis using a ‘SenseWear Pro 3’ armband device for monitoring daily activity. The patients wore the armband all day every day for 5 consecutive days including three week days and two days at the weekend. They worked out energy expenditure (METS) and compared it to values expected from age matched controls. They also examined the relationship between the BASDAI and the actual mobility measured. They did find that AS patients had a lower level of physical activity than controls (especially in the vigorous or very vigorous activity ranges) but did not find that the BASDAI correlated with the degree of difference in activity compared to controls.

  • The SenseWear Pro 3 armband has been validated as a tool capable of measuring energy expenditure fairly accurately. However, the location of the sensor may not be optimal for measuring mobility restriction in AS.
  • The two groups were fairly well matched, but the Healthy Control group had a significantly higher proportion of patients in employment than the AS group. Whilst this is not surprising, it might have been better to only include people in employment in a study like this. Although they attempted to control for this effect, the low numbers in the study may have made detailed analysis difficult.


    • This is one of the first papers to measure daily mobility accurately in patients with AS and to attempt to relate this to the BASDAI. A previous study by Plasqui was limited by a very small group size and the use of a less accurate pedometer measurement tool.
    • The authors have employed a well-considered methodology for making sense of the level of physical activity measured by these devices and they have demonstrated that patients can wear them for >90% of the 24 hour periods studied.
    • The study did not report on variations in BASDAI/mobility over time which probably would have been more informative.

stepActivityThe third article in my brief review is by Prioreschi et al in Rheumatology (May 2014). This was a small study studying the effect of DMARD therapy in 18 RA patients using accelerometry and compared results against a matched control group. They also recorded the duration of morning stiffness and more typical CDAI and HAQ score assessments. The patients wore Actical accelerometers for 2 consecutive weeks. Significant improvements in CDAI, HAQ, CRP, and duration of morning stiffness were found after 3 months therapy, and there was also an improvement in the level of moderate physical activity at the end of the study.

  • This is probably the first study to split the day into segments for comparing functional activity: they found that RA patients were less active in the morning and early afternoon, but that this difference from controls disappeared after DMARD therapy.
  • This is one of the first studies to relate the duration of stiffness against the measured activity levels. The results give objective confirmation that activity levels are related to the symptom of stiffness
  • The minimum required % of the day spent wearing the accelerometer was not specified in the paper.
  • The decrease in CRP was found to be related to the increase in moderate activity by multivariate regression analysis.
  • The authors have shown that this methodology can be used as a sensitive outcome measure for detecting changes in habitual physical activity
  • The authors commented that most of the participants were obese: the reliability of hip/belt worn accelerometers can be reduced in this group. However, the finding that DMARD therapy actually leads to increased moderate intensity physical activity in this group is even more likely to lead to health improvements in general.

Overall, I am really encouraged by these studies. I think we are going to learn a lot about our patients over the next few years as we get down to studying the impact of our treatments on their daily activity. I can see this sort of data (‘observations of daily living‘) being incorporated into the medical record and used to provide virtual ‘nudges’ to encourage patients to keep up their exercise programmes. Of course it will only be of benefit if it is done carefully & part of a rehab programme that the patient really wants to follow.


Would you be my Bematist?

alexander-the-great-mapIf I had been around when Alexander the Great was looking for volunteers I definitely would have looked the other way. History tells us that he employed two men – Diognetus and Baeton – as ‘bematists’ to accurately count their steps and thereby measure the distance between cities as his army marched through Asia. Quite how they managed to achieve astonishing levels of accuracy is sadly not recorded, but that is one job I would certainly not have signed up for! Strange as it may seem, but accurate step counting is back in fashion!

The proposal I am going to discuss in this article is that accurate monitoring of physical activity should now be adopted as a standard outcome measure for research in arthritis and sponyloarthritis.

I make no claim to originality here. When I was a trainee in Newcastle upon Tyne in the early 90s, David Walker introduced me to an activity tracker called the NUMACT monitor. Using this monitor, his group quantified the improvements in the actual daily mobility of RA patients after knee injection (70%), and after NSAID use (50%). They then showed a significant (79%) improvement in mobility in OA patients six months after total knee arthroplasty. He compared these results to questionnaires that ask about physical mobility (such as the Nottingham Health Profile) and reported significant differences. Until recently, there had been very few other such studies in patients with arthritis, and I believe that it is about time we followed his forward thinking approach. Before we take a look at these studies, let’s review the rationale for going to all this trouble.

The stated aim of the International Classification of Functional Disability and  Health (ICF) is to “put every person in a context: functioning and disability are results of the interaction between the health conditions of the person and their environment”. They suggest that a new framework for outcome measurement is required, and in the area of assessment of general physical mobility we need to look at the issue through three different ‘lenses’. The first is to use self-reported assessment of problems in daily function using questionnaires such as the HAQ. The second is to measure physical activity under ‘laboratory’ situations (e.g. a ‘six minute walk test’) and the third is to monitor physical activity in the patient’s natural environment (at home, work etc.). This has to be a positive move for patients, as it will help to ‘re-set’ our target towards one that will get our patient back participating fully in their ‘natural environment’ (work, home and leisure).

At the moment the only one of these included as a ‘core outcome measure’ by EULAR/ASAS is the questionnaire assessment. There is no doubt that this is very useful and relatively easy to collect as part of a research project. But ultimately the goal of our treatment has to be to get the person back to the optimal level of function in real life. So can a questionnaire such as the HAQ accurately tell us when the patient’s function has returned to normal? Certainly not: there is a ‘floor effect’ that will not detect changes between no disability and low-moderate disability. And how can you really take account of aids and adaptations? Does the HAQ correlate well with 6 minute walk tests or activity monitoring studies? The research here is still a bit patchy, but it appears that these three ways of measuring of function may have quite different stories to tell.

stepwatchWe should perhaps eat a little humble pie and learn from our orthopaedic colleagues. In the past the success or failure of hip replacement was mainly judged by measuring standard surgical outcomes such as mortality and morbidity but for some years now they have realised that with a younger and more active group of patients the expectations of a good outcome are higher. Surgical success rates are higher than patient satisfaction rates for both hip and knee arthroplasties, and actual improvements in physical activity can lag even further behind. This is a problem, as we have always assumed that an important goal of these operations is to return the patient to a relatively high level of physical functioning. A study by deGroot et al (2008) looked at recovery after hip and knee arthroplasties using all three methods: the SF36 questionnaire, the 6 minute walk test and monitoring daily activity using an accelerometer device. This study reported substantial improvement in self-reported physical activity whilst daily physical activity had not improved to anywhere near the same extent. This surprising result will hopefully lead to renewed efforts to improve rehabilitation programmes.

I also look across at the nearby cardiac rehabilitation clinic with some admiration. Research has shown that a good ‘medical’ outcome after acute myocardial infarction is often followed by a significant loss of mobility and participation in normal activities, and the success of cardiac rehabilitation programmes has been most impressive. What amazes me is how well motivated their patients seem to be in sticking to the rehab plan! I think that our patients who continue to suffer from pain and stiffness due to their chronic arthritis probably need a little more help and encouragement using technology such as activity monitors. In a small but important randomised study Talbot (2003) showed that in patients with symptomatic knee OA, a 23% increase in monitored physical activity was seen in the group given a pedometer with a specific rehabilitation plan whilst those who were given normal education advice showed an actual fall in performance. A striking difference between groups was also evident in tests of isometric muscle strength (the ‘laboratory’ test). This sort of study should give us hope that outcomes can be improved by employing technology in targeted rehabilitation programmes.

So, if we’re all agreed that this is a laudable thing to try and measure, what then should we be measuring and what is already known in this area? ‘Physical Activity’ has a technical meaning in Sports Medicine that many readers may not be aware of: it is all about energy expenditure in METs rather than just measuring steps or miles. If we are talking about achieving high intensity in daily physical activities we need to measure more than the number of steps. In my next post we’ll have a closer look at the approach chosen by a couple of recent studies. I’ll also be having a look at some of the technology out there with an emphasis on the scientific validation of the different monitors. And of course, I must emphasise that at the moment I’m just looking at general function rather than specific joint movements of relevance to the specific disease in question (such as the electronic goniometric glove, for instance).

And by the way, I didn’t know what a Bematist was either – but I thought it might get your attention!



Carrots and Sticks in the Workplace

amazon-warehouse-4In many ways you have to admire Amazon as a business.

They do organisation very well. They do big data very well. They collect and make use of their customer’s opinions in a way that has to be admired.

However, there are some who suggest that from an employee’s perspective, things might look a little different. A Panorama documentary recently exposed some of the ‘incentives’ used to encourage maximum productivity among the ‘pickers’ in their warehouses. This has also been the subject of an excellent article by Sarah O’Connor in the Financial Times.

What is not in doubt is that Amazon closely monitors their workers’ movements in order to increase the speed and efficiency of their work. The workers carry computer bar-code readers that count them down to the next ‘pick’ and start beeping when they make errors or get too far behind. As the worker’s performance improves, their targets are increased progressively. They meet with their managers regularly to discuss their performance and temporary workers face the prospect of early ‘release’ if they under-perform. This sort of intensive monitoring may be commonplace in the U.S., but in the U.K. the reaction has suggested that Amazon may be favouring stick more than carrot. So is it the monitoring that causes stress or is it the incentive? What if instead of being afraid of a penalty you could win a prize for the best performance of the day/week? What if you got a bonus for doing more than your target? What if you were competing for the best ‘team’ in the warehouse? I’m sure there are many workers who would westatsportslcome the challenge.

viper_podAn exciting example of the high-tech monitoring of movement at work is the use of the ‘ViperPod’ by most of the UK Premier League football and rugby clubs as well as GAA clubs such as Tyrone. An article in the Daily Mail shows how this small device captures a wealth of highly accurate information about the sportsperson’s movement, energy expenditure and physiological state. The Irish company STATSports now has an impressive international list of clients. Sports scientists Alan Clarke and Sean O’Connor have cleverly combined the latest gyroscope/accelerometer sensors with high frequency GPS and radio-frequency transmitters allowing detailed information on each player on the pitch to be analysed in real-time at the pitch side using their proprietary software. One of the STATSports analysts explained to ‘TheScore’ how this information can be used to prevent injuries as well as optimise performance. The way in which clubs use this information to influence their players could have either a positive or negative effect on their productivity and creativity.

Employers have started to look at using ‘gamification‘ techniques to boost employee health and productivity. Can measuring movement be used to create positive incentives to healthy lifestyle behaviours and improve employee health? Blue Shield have used several, including Shape Up Shield and MeYou. Healthrageous used personalised coaching to encourage healthy choices among employees via their mobile devices, but the business failed to thrive and it was taken over last year by the health and insurance giants Humana. Should people be given a discount if they can prove that they are adopting a health active lifestyle? Or is this an invasion of privacy?

So, what has all this got to do with the jobbing Rheumatologist? Perhaps not very much, but we’re clearly reaching the point where monitoring ambulatory activity in an accurate and scientific way is both feasible and affordable. And it is also becoming clear that this information can be used to alter behaviour, promote rehabilitation and perhaps even prevent injury. In my next post I’ll be looking at the first attempts to measure ambulatory activity as an outcome in arthritis patients.

Measuring Movement by Movies: a Wager, a Murder & an Invention

Eadweard Muybridge was born in England in 1930. He moved to New York at the age of 20 and later developed an interest in the new technique of photography. He gained a reputation as a photographer with an incrediMuybridge-The_Horse_in_Motionble dedication to his art. He came to the attention of a wealthy former governor of California, Leland Stanford, who was also the owner of race-horses. There had been debate for many years as to whether or not all four hooves left the ground, but in spite of the observations of many racing experts nobody had been able to come up with a definitive answer. The human eye simply could not analyse and break down such complex and rapid movements. Stanford decided that Muybridge would be the perfect man to provide the proof and help him win a $1 million wager with his friends. Muybridge approached the challenge with enthusiasm, showing both a creative genius in coming up with new inventions to capture the images as well as a highly scientific approach to his ‘research’ into equine movement. In 1872 he produced the first conclusive evidence using a single photograph of a horse with all four hooves in the air. With today’s cameras that doesn’t seem too difficult, but consider that Muybridge had at his disposal the sort of plate cameras that normally were only used for the most static of subjects. Faced with the seemingly insurmountable obstacle of inadequate equipment, he invented an ingenious electromagnetic shutter system that would enable him to ‘freeze’ movement to 1/1000sec. Soon he had rigged up a series of 12 of these cameras along a carefully marked track in Palo Alto – resulting in the sort of ‘movie’ you can see below. His methods were more recently employed in putting together the slow ‘bullet-time’ motion sequences of the film ‘Matrix’. In spite of his early success, he wasn’t satisfied with these studies, and continued to perfect his technique between 1978 and 1884. Along the way, he invented the zoopraxiscope which enabled him in 1893 to show his moving pictures to a paying public for the first ever ‘movie theatre’. Sadly, Muybridge didn’t get the credit he deserved: a subsequent book published by a friend of Stanford ‘Horse in Motion’ used uncredited illustrations based on Muybridge’s photographs. His lawsuit was dismissed out of court.

MuybridgeBoys_playing_LeapfrogIn the 1880s the University of Pennsylvania commissioned him to do a series of studies on humans and other animals. Muybridge’s obsessive work left behind an enormous body of work that was truly groundbreaking in the study of human biomechanics. According to Wikipedia, ‘In 1887, the photos were published as a massive portfolio, with 781 plates comprising 20,000 of the photographs, in a groundbreaking collection titled Animal Locomotion: an Electro-Photographic Investigation of Connective Phases of Animal Movements.’ His human models were photographed in front of a measured grid background & in his work he showed a dedication for both scientific accuracy and artistic merit.

There was a darker, more mysterious side to Muybridge that has fascinated historians ever since. He sustained a severe head injury in a stagecoach accident in 1860, and his friends later commented on a change in his character. At this time he returned to England and changed his career from that of a bookseller to that of a professional photographer. In 1872, Muybridge married Flora Shallcross Stone, then aged 21 i.e. half his own age. Two years later he came to believe that his wife’s ‘friend’ Major Harry Larkyns had fathered his son Florado. He traveled to California to track him down and shot him dead at point-blank range. When he was subsequently tried a jury found him not to be suffering from insanity, but instead acquitted him on the grounds of ‘justifiable homicide’. Did his head injury make him mentally unstable? Did it contribute either to his creative genius or to his obsessive-compulsive tendencies? No doubt psychologists will continue to debate the issue.

So what can the rheumatologist learn from such a remarkable man? Apart from the rather obvious observation that our lives are very mundane by comparison, here are a few thoughts…

Muybridge showed how little we know about the science of movement, and on his own he set out to answer a clear question about whether or not all of a horses hooves leave the ground during a trot. He found that indeed they do, but not in the extended position depicted by the artists of the day. Instead, they were off the ground when curled under the horse. To answer this question, Muybridge had to use all of his creative skills and apply a technical and scientific approach to his quest using the latest technology available to decipher what was ‘invisible’ to the naked eye. This was not exactly a pressing scientific question of the day, but this simple quest led to so much more. His work would predate the ‘gait analysis lab’ by over a century.  One suspects that Muybridge would have been in his element in today’s world when there are a plethora of devices to measure movement. One of the criticisms of wearable technology is that nobody has really thought out how best to use the data to answer important questions to better the lives of ordinary people.

So here’s my challenge: If you were able to drum up support for a modern £10 million wager, what question would you ask someone to answer about human movement? 



Bean-counters, Lamp-posts and Rheumatologists

bean counterI was talking to some medical students recently about the use of outcome measures in rheumatology. I happened to mention that ‘big data’ was the next ‘big thing’ in medicine. Cue blank faces. Followed by quizzical looks and a sly smile. I suddenly realised to my chagrin that not everyone has read Topol’s ‘Creative Destruction of Medicine’ and that my students are beginning to doubt my sanity. I rapidly tried to regain some semblance of dignity by explaining that outcome measures are all the rage in rheumatology right now.

Readers of my blog may have not be surprised to hear that at times I can get a little obsessive about the science of measurement in medicine. So as a form of necessary self-therapy and reflection I am going to explore the darker side of measurement science using a couple of well-known quotations.

einsteinblackboard03The first quote, usually attributed to Albert Einstein (but possibly more accurately credited to a Professor of Sociology, William Bruce Cameron), is as follows:

“Not everything that can be counted counts, and not everything that counts can be counted.”

So not everything we measure or count actually matters. We need to be very selective before we decide that some measurement is essential or routine. There seems to be an assumption that the more we measure the more scientific our care will be and therefore the outcomes will improve. In the case of rheumatology there is now an assumption that if we have a patient with rheumatoid arthritis and we do not complete a ‘disease activity score’ and a disability assessment in every patient we are in some way negligent as doctors. Now I would be the first to argue that early arthritis trials have demonstrated the need to adopt a ‘treat to target’ approach using objective and quantifiable measures to gauge response – but to extrapolate this to patients with 30 years of arthritis may not be either scientific or kind to the person in front of us, particularly when they mention that they have had a recent bereavement. In times like these, ‘feeling the pain’ will often trump feeling the joints. Some measurements may be eminently ‘scientific’ but completely worthless, particularly in managing the individual.

The second part of this elegant chiasmus claims that not everything that counts can be counted. I hope that every health care worker is acutely aware of this fact, but it is at the core of an empathic approach to medicine. How the patient feels cannot easily be reduced to a score on a questionnaire. How well does the doctor understand the narrative from the patient’s perspective? Can we really quantify how well or badly the doctor or nurse empathises with their patient?  There is a feeling that recent changes in the organisation of medical work have disrupted the continuity of care and the integrity of the ‘team’ looking after the patient. Medical ‘clerk-ins’ are reduced to ticking boxes in lengthy proformas and medical handovers are reduced to a rapid fire exchange of facts and figures. Increasingly, doctors complain of being tied to the computer screen completing page after page of data, and having no time to have a proper talk with the patient.  maninfogIn the midst of this swirling fog of data, have we lost sight of the patient? When we teach our students the importance of rigorous data collection and outcome measurement, will we remember to refocus their attention back on the importance of empathy and the art of medicine?

The second quotation has been attributed to AE Houseman or Andrew Lang:

People Use Statistics as a Drunk Uses a Lamppost — For Support Rather Than Illumination


This is justifiably a popular quotation and any medical researcher worth his or her salt will doubtless be familiar with the dark arts of manipulating statistics to make the data seem to support your hypothesis. Reviewers of publications have become wise to this, and statistical scrutiny is a little more rigorous than it used to be. Even better, clinical trials registration requirements and ethics reviewers will insist on you defining the primary and secondary outcome measures before the study begins. This only goes to prove that nowadays you need a higher level of statistical jiggery-pokery’ to baffle your readers and ‘stay ahead of the game’.



Managers Use Statistics as a Dog Uses a Lamppost — For ‘Marking their territory’ Rather Than Illumination


The third quotation could be attributed to a certain PV Gardiner, the writer of this blog. He has clearly borrowed heavily from the afore-named Andrew Lang. He has also used polite and politically correct language within the quotes which readers may wish to replace with more descriptive and direct terminology.

I’ll tell you a story to illustrate the point. A few years ago we were told that we were obliged to carry out an ‘audit’ on our use of biologic drugs in the region. Nothing unusual with that, you may say – they are very expensive drugs, after all. However, we did detect quite a hostile and accusatory sub-text to the discussions. After a little ‘digging’ we discovered that somebody  in management ‘on-high’ had ‘discovered’ that we were using biologic drugs twice as much as the average in the UK. We thought we were using the same NICE guidelines to treat similar patients, so this seemed odd. Cue some anxious head-scratching and navel-gazing by the chastened rheumatologists. Strangely, our own figures hadn’t seemed to suggest any problem at all. Eventually, we discovered that someone in management had been using a single figure (the prevalence of RA in our region) that had changed everything. This figure suggested that RA was only half as common as in the rest of the UK. We were most intrigued. Could it be something in the pure Irish spring water? Could it be our fondness for Guinness or Bushmills whiskey? How had they arrived at such a figure, when there had never been a study of the epidemiology of RA in our region? We have never had a diagnostic database to record the prevalence of RA. In fact, they had obtained the figure from a reference found in none other than the official National Audit Office report into RA in England. That article had briefly referred to comparative data in other nations, and the quoted statistic actually came from a paragraph in a local newspaper where a journalist had mentioned in passing the estimated number of people with RA in our region. Well, it is just as well that we discovered the source of these scurrilous rumours. Otherwise the aforementioned honourable rheumatologists might well have wound up propping up the local lamp-posts (or was that the other way round?). We live to fight another day…


What are we doing to make our service safer?

scaffold safetyI was speaking to a man recently who had worked all his life as a scaffolder. I asked him about advances in safety since the early days. He told me the story of when he worked on scaffolding 23 stories up on a building site in London many years ago. He seemed proud of the raw bravery you had to have in those days, but in hindsight he can’t believe the risks they took at work every single day. One day his foreman called him to join him on some work on the next floor. For some reason he didn’t go immediately and just a few minutes later his shocked workmate informed him that tragically the foreman had just walked over some loose boards and fallen 24 stories to his death. The scaffolder spoke about the incident as if it was yesterday and he still wonders why he hadn’t died that day. Safety regulations on building sites have dramatically reduced deaths and workmen these days wouldn’t dream of taking those risks. In the case of the health service, we as health professionals are not taking risks with our own safety but with that of our patients. So reducing risk – ‘first do no harm’ – should always be at the core of our professional integrity. In today’s uneasy climate it doesn’t take much to bring the great weight of ‘quality inspectors’ and intense media attention to bear on a hospital and its services. At the moment this level of scrutiny is still quite infrequent, and people may get the impression that patient safety is not embedded into routine practice. It is high time that we all started to reflect on what we are doing to improve patient safety and let people know what we’re doing. High risk specialties involving high risk surgery or obstetrics are well used to reporting deaths to confidential enquiry programmes such as ‘CEPOD’. In some cases, particularly in the U.S., these statistics are available to the public and not anonymised. In lower risk specialties such as Rheumatology the measures of safety and quality are harder to measure. The safety measures listed below are gradually being incorporated into routine practice. Here is a provisional list of some of the measures we currently use in our Rheumatology unit to promote patient safety:

  • We report serious drug adverse effects using the ‘Yellow card’ post marketing surveillance run by MRHA. This is a voluntary reporting scheme: some report more than others, but it can help to pick up problems that haven’t surfaced in the drug’s development. We also contribute to a national ‘risk registry’ for the newer biologic drugs (BSRBR).
  • Morbidity reporting for infusion reactions. In the past year we noticed quite a high incidence of allergic reactions in our unit to Iron Dextran infusions: following discussions with specialists and pharmacists we have changed to another preparation with a lower risk of reaction. None of the reactions were serious, but it is still a patient safety issue.
  • Clinical Incident reports – actual harm or near misses. Our hospital has a database for this and the risk management team rate incidents as green/yellow/red by risk level. We contribute to this, mainly for the more serious incidents. These incident reports are looked at centrally and there isn’t normally much discussion at a local level. It is therefore difficult sometimes to see whether anything changes when problems are identified.
  • In our unit, we have started holding regular ‘Mortality and Morbidity’ multidisciplinary meetings – using a clear unambiguous format. These meetings take place once a month and take a few hours to prepare and write up.
  • Multidisciplinary clinical discussions about unusual imaging reports or difficult diagnostic or treatment decisions. We have a good meeting with radiologists to discuss x-rays and scans, but we could probably do better in discussing difficult cases with our peers. It is very difficult to find a time when all clinicians are free.
  • We use (and helped to develop) agreed regional shared care guidelines for ‘disease modifying drugs’ which used to be thought of as drugs with a lot of side effects. We record in the notes that these have been issued with every prescription and we check that monitoring is carried out when patients attend clinics. In our system the General Practitioner or Family doctor has responsibility for monitoring blood tests. We try to record telephone calls for advice, but this is an area we can improve on, perhaps by using email more often. We also standardise patient information about these drugs – we give out booklets but make sure that the patient understands the most important issues.
  • We are responsible for monitoring blood tests for patients on biologics drugs – our pharmacist and specialist nurses take responsibility for this and use an agreed protocol.
  • When we conduct research, we adhere to ‘good clinical practice’ standards and the international statement of Helsinki. We are also regularly monitored by the Trust’s R&D department and have to provide annual reports. Each study has to have prior approval by a regional (and very detailed) ethics review body.
  • We have a discussion of major drug safety alerts or other safety alerts at our monthly multidisciplinary meeting.
  • We carry out regular audits – for instance, this year we looked at the accuracy of Methotrexate prescriptions in patients admitted to hospital. This has led to several proposals to help ensure that mistakes are reduced/identified before a patient can come to harm.
  • Each doctor who works in the unit has to undergo an annual appraisal. For consultants, this includes a review of statistics including mortality & a comparison with peers. There is also a discussion about any complaints, incidents or legal cases. Each doctor has to sign a probity and health statement. Every five years a doctor in the UK now has to undergo revalidation. This assessment has to include two confidential surveys about the performance of that particular doctor – one from patients  and the other from health professionals with whom they work.

This is not an exhaustive list, and it doesn’t mean that there aren’t areas in which we need to improve. For instance, we don’t yet use a clinical database, and we don’t have any link to the patient’s prescription list held by their GP. We don’t participate in a peer review programme – this doesn’t yet exist in our region. These are significant developments that may contribute to patient safety – but they have to be properly resourced and supported by our hospital’s management.

A Focus on Patient Safety: time to sharpen up our act!

There seems to be no end to medical scandals in the media. In the UK, the focus recently has been on the Francis Report into care at the Mid-Staffordhire NHS Foundation Trust. The report found that there had been a focus on targets rather than on patient safety and quality of care. A real concern was expressed about the apparent silence of medical staff in raising concerns about the problems. The recommendations of the Francis report are wide ranging, but it is a wake up call for health professionals to take ownership and responsibility for the safety of patients under their care. We need to ask serious questions about quality of care and be prepared to speak out to expose problems – even when we do not have a ‘managerial’ responsibility.

If you can spare an hour of your time, why not have a look at this video from the patient safety congress. Thanks to Anne Marie Cunningham (@amcunningham) for sharing it. The first talk is by Jeff Skiles, an experienced airline captain who recently had to ditch his plane into the Hudson river – the second is by a doctor who is trying to apply some of the lessons learned in aviation in the health care situation. Note that his co-captain Sully Sullenberger also lectures on aviation safety (@CaptScully).

At the recent NI Confederation conference in Londonderry (#NICON13 on Twitter) one of the speakers from the Southern Health Trust Hugh McCaughey gave us six safety questions every service should be asking of themselves.

  1. How can we prove that our service is safe?
  2. What are our team’s objectives?
  3. What would success look like to our team?
  4. Can you provide evidence that we are learning lessons as we go along?
  5. What do users think of our service?
  6. What outcomes are we achieving?

These are tough questions, but I think that it is a useful exercise. In the next series of posts I am going to look at each safety question in turn for our own service. I will be asking other members of the team to contribute to this discussion so that our final statement will be agreed by the team.

Arth-rit-is-is- not-right

Sometimes we are so busy doing our activity scores we don’t have time to really listen to what our patients are saying. Dorothy Logue is a talented poet who also happens to have rheumatoid arthritis – she has very kindly agreed to share this poem with us…

‘Arth-rit-is-is- not-right’

I am not my usual self, for days I’ve felt unwell.
I’ve lost my mojo, anyone who knows me can tell.
I feel so ill, my back hurts, my arms and legs hurt too,
My neck is so sore, I really don’t know what to do.
I could ring the doctor again, what good would that be?
I could go visit him but there’s nothing new to see.
I cannot drive today, my fingers are so sore.
I can just complain and mope and it is such a bore.
No one knows how I feel, I can’t make them understand,
When you feel as low as this, your thoughts get out of hand.
I’m not a hypocondriac, nor one to complain,
I could whinge all the time but that would be in vain.
Unless you are a sufferer, you wouldn’t believe
The lengths I will go to, to have the pain relieved.
Maybe tomorrow morning when I get out of bed
I will feel much better and love the day ahead.
Days I ask myself questions, there are no answers back,
Days I go out and enjoy myself, life is back on track.
I keep my pain and suffering private so no one will ever know,
They only see the “ME” which I force to “get up and go.”

by Dorothy Logue