Nosology and Cut-Off Values for Axial Postural Abnormalities in Parkinsonism

[00:00:54] Dr. Michele Tinazzi: Good day, everyone. I'm Michele Tinazzi. I'm a Full Professor of [00:01:00] Neurology and the head of the Movement Disorders Unit at the University of Verona, Italy. I would like to thank the Movement Disorders Society for giving us the opportunity to present this podcast dealing with the preliminary data of our MDS Task Force on Axial Postural Abnormalities in Parkinsonism. According to the mandate of the International Parkinson and Movement Disorder Society task force on Postural Abnormalities in Parkinsonism. We present our consensus study on the nosology and the cut-off values of postural abnormalities recently published in Movement Disorder Clinical Practice Journal.  I would like to thank all senior and young members involved in task force for their relevant [00:02:00] contribution and appearing in this first manuscript. 

So thank you again the Movement Disorder Society and the senior and young members of this task force. 

[00:02:12] Dr. Hugo Morales: Thank you, Professor Tinazzi. I would like to take this opportunity to actually have some insight from your experience and this is relevant for the audience as well, but can you tell us a little bit of some of the clinical perspectives of this study. So what are the postural and abnormalities in parkinsonism and how frequent they can be in Parkinson's disease? And so also an idea on how much these axial or postural abnormalities can effect these patients in daily life? 

[00:02:45] Dr. Michele Tinazzi: Postural Abnormalities are motor symptoms, complicating the clinical picture of patients with parkinsonism and they are referred as an abnormal spine flexions appearing in [00:03:00] different conditions, for example, while sitting or standing and worsened during walking and usually reversed in lying position. So they are frequent complications in Parkinson's disease. The estimated prevalence in Parkinson's disease, as we published in a previous multicenter Italian study is about 20% including camptocormia, Pisa syndrome, antecollis, or even higher when considering mild forms. So they are relevant in terms of epidemiology and can occur either in high related or combined forms and can be accompanied by other muscular skeletal comorbidities like scoliosis. And most importantly, they are associated with an increased prevalence of back pain, sometimes falls, high level [00:04:00] of disability with a reduced quality of life. 

[00:04:03] Dr. Hugo Morales: And moving into one of the aims of the study. So I wonder what was the rationale behind the idea of actually establishing a consensus for axial postural abnormalities? And I know that in the past, that several studies of sort of cohorts have established sort of not only the prevalence, but also the descriptions of these axial abnormalities, but this, study is new in terms of defining what actually are these axial abnormalities. So again, can you describe for us, what was the rationale behind developing this consensus? Please. 

[00:04:42] Dr. Michele Tinazzi:  Yes, despite such a remarkable clinical impact, the pathophysiology of this motor complication remains largely unknown, and the current pharmacological and known pharmacological treatment options may at best offer only [00:05:00] short term partial improvements. The progress of research in the diagnosis, management and prevention of these motor complications continues to be hampered by two basic issues related first related to the lack on consensus on nosology and cut-off values leading to an extreme heterogeneity in the literature and for this reason, the rationale behind this consensus and this task force is first to reach a consensus regarding the nosology and the cut-off values. 

[00:05:38] Dr. Hugo Morales: Yeah so, I think that this is important for moving into large clinical trials addressing these problems of axial postural and abnormalities in Parkinson's disease. So overall, what, what the study was aiming for is to, to bring order into the definitions as far as I understand. Now [00:06:00] let's move to Dr. Carlo Alberto Artusi and Dr. Artusi, would you like to introduce yourself? And then let's move to the questions. 

[00:06:09] Dr. Carlo Alberto Artusi: Hello everyone. Thank you very much for the kind invitation I'm Carlo Alberto Artusi. I'm an assistant professor in neurology, working at the Department of Neuroscience at the University of Turin. I'm a member of the task force on postural abnormalities in parkinsonism. So I participated in coordinating this effort for reaching a consensus on nosology and cut-off criteria for postural abnormalities in parkinsonism. 

[00:06:38] Dr. Hugo Morales: Thank you, Dr. Artusi. Now, can you explain to our audience how this consensus is reached and what is that Intel for other experts to do, evaluate or define, to just sort of make a homogeneous consensus for these descriptions and also [00:07:00] can explore briefly the definitions based on the consensus about Pisa syndrome, camptocormia, and antecollis. 

[00:07:09] Dr. Carlo Alberto Artusi: Yes. Sure. The, the study methodology was based on obtaining an expert consensus by means of a Delphi panel approach on two main aspects. As said also by professor Tinazzi previously the nosology of postural abnormalities in parkinsonism and the cut-off. The Delphi approach is a method to achieve convergence of opinions among a panel of experts, and in our case, these are the senior members of the Movement Disorder Society task force on postural abnormalities. 11 movement disorder specialists encompassing, not only neurologists, but also neurosurgeons and physiotherapists were selected to answer questionnaires through several rounds of two different sequential surveys. 

The first one related to the [00:08:00] nosology and the second one on cut-off criteria. Finally, these agreements were solved by web-based meetings to promote an interactive discussion before reaching a final consensus. So for the first part of the project, the one on nosology experts were asked to choose the best term to define different postural abnormalities commonly seen during clinical practice by anonymized questionnaires. 

An example of a question was which term is the most appropriate to identify reversible severe lateral trunk flexion in a patient with Parkinson's disease and panelists at a wide range of choices based on a preliminary literature review on the topic. And in the first round of the survey, they also had the option to propose a term that was not enlisted in the questionnaire. 

And a consensus for each question prepared in the surveys was pre-defined as [00:09:00] at least 70% agreement among the panelists. And so the same survey was then resent to all panelists, excluding the items for which a consensus was already reached and for the aspect still leading consensus, narrowing the list of options to those chosen at least by two panels during the previous round. 

So I think that in my opinion, the most interesting achievement of this part of the study is the classification of two different types of postural abnormalities in parkinsonism. The classical, severe forms, as you already mentioned so camptocormia, Pisa syndrome, and antecollis and another group of postural abnormalities, which represent clearly abnormal posture, but not severe enough to be defined, camptocormia, Pisa syndrome, and antecollis. 

And in this way we have, let's say officially recognized for the first time that mild lateral flexion, for instance, five degrees of bending of the trunk on the right is a disease [00:10:00] sign in postural abnormalities, But now with its own name, specifically lateral flexion, even if it does not reach the level of severity, commonly used to define Pisa syndrome. 

Thus at the end of this first step, we have reached an agreement on the terms Pisa syndrome, camptocormia, and antecollis, for the severe forms of axial postural abnormalities, and on the terms, lateral trunk flexion, anterior trunk flexion, and anterior neck flexion for those postural abnormalities not reaching the severity to be called Pisa syndrome, camptocormia, and antecollis. Importantly, we have agreed to acknowledge that the terms camptocormia and anterior trunk flexion should always be reported along with the level of the fulcrum of the trunk bending specifically the lumbar fulcrum or thoracic fulcrum. 

[00:10:53] Dr. Hugo Morales: So there's clearly yeah. Sorry. 

[00:10:55] Dr. Carlo Alberto Artusi: Oh, this is about the first step of the study. 

[00:10:58] Dr. Hugo Morales: So just to recap. So there's [00:11:00] clearly a differentiation between the camptocormia with a thoracic and lumbar and Pisa syndrome and antecollis are defined now with a specific category of severity or the most severe spectrum of this. And then there's an intermedium category when they're determined to be anterior trunk flexion and the lumbar for thoracic spine and also anterior neck flexion. Is that correct? 

[00:11:26] Dr. Carlo Alberto Artusi: Yeah, that's correct. 

[00:11:27] Dr. Hugo Morales: Okay. And then. 

[00:11:28] Dr. Carlo Alberto Artusi: And lateral trunk flexion. 

[00:11:29] Dr. Hugo Morales: Exactly, now in regarding cut-off values. Is it something that I can see just by reading the paper, this is something that hasn't been done before. This is a new category. So is it highly recommended for neurologists and movement sort of specialists to solve this differentiation or different values as well? 

[00:11:51] Dr. Carlo Alberto Artusi: Yes, this is quite new because a previous consensus was reached about camptocormia, but not about [00:12:00] the Pisa syndrome and antecollis first of all. And second one, we also would add this important aspect of the, let's say, milder forms of postural abnormalities. So the second step of the project, and to reach a consensus on the cut-off to distinguish normal postural from mild postural abnormalities and mild post abnormalities from severe postural abnormalities. A similar methodology of the previous with Delphi panel approach was used for the second survey. However, in this case, we used the support of patient's pictures and we asked panelists to apply the terms decided in the previous survey to describe patients with different degrees of trunk or neck flexion. And to make a longer story short. We finally agreed on the following definition presenting the paper. So we have lateral trunk flexion in Parkinson diseases and involuntary trunk flexion on the right or on the left of over five degrees, but inferior to [00:13:00] 11 degrees while Pisa syndrome is an involuntary trunk flexion on the right on the left of over 10 degrees. Anterior trunk flexion was differently judged according to the level of the fulcrum thoracic or lumbar and considering the thoracic fulcrum we agreed that an angle lower than 25 degrees was considered a normal posture, between 25 and 45 degrees an anterior trunk flexion, and over 45 degrees is camptocormia. Considering the lumbar fulcrum, meaning the flexion of the lower part of the spine or hips. We agreed on the term anterior trunk flexion with an angle between 16 and 30 degrees and camptocormia with an angle of flexion over 30 degrees. Finally we define anterior neck flexion an involuntary flexion of the neck or the spine between 36 and 45 degrees and antecollis trunk flexion over 45 degrees. 

[00:13:58] Dr. Hugo Morales: And Dr. [00:14:00] Artusi just for the clinicians listening to this podcast. Is there any way that you would recommend to do these measurements in these patients? 

[00:14:08] Dr. Carlo Alberto Artusi: Yeah, sure. To measure the angles of trunk flexion, we relied on previously validated method based on quick and simple measurement by drawing a few lines on pictures of patients standing frontally or sitting against a wall. So it is quite easy and quick, but there is also available a free web based software provided by the University of Kiel and developed by Dr. Margraf that is one of the task force members, called NeuroPostureApp, which is free and easily searchable by Google, which allow a very easy and time saving evaluation of all these angles in a couple of minutes. 

[00:14:48] Dr. Hugo Morales: Okay, thank you. Now let's move to Dr. Christian Geroin. Dr. Geroin would you like to introduce yourself. 

[00:14:55] Dr. Christian Geroin: Yes, good day everyone. And thank you very much for this kind invitation. My name is Christian [00:15:00] Geroin I'm assistant professor at university of Verona, Italy. And I'm one of the author contributing in this work. Thank you. 

[00:15:10] Dr. Hugo Morales: Thank you, Dr. Geroin. Now one of the questions I think will be also important now that we have a consensus on axial postural abnormalities in parkinsonism. So what is the changes or the impact that will have this consensus and clinical trust in Parkinson's disease regarding device assisted therapies or other or normal therapies for Parkinson's disease. 

[00:15:34] Dr. Christian Gerion: We believe that this consensus will have an impact in all patients with the Parkinson disease. And I mean, not only in the advanced stages of diseases on which is more frequent, and it will have an impact in both research and clinical practice for many reasons. First of all, the early recognition of postural abnormalities. This is an important point because the early [00:16:00] recognition of postural abnormalities promote the prompt establishment of treatment strategies including medical therapy, such as the dopaminergic medication, DBS or botulinum toxin injection, but also non-pharmacological interventions, such as physiotherapy and lifestyle changes. All these actions are used to avoid evolution toward structured, fixed postural abnormalities, leading to severe mechanical constraints, affecting respiration, mobility, postural stability, and therefore increasing the risk of falling. This is the first point. The second reason is to improve the assessment of these patients with postural abnormality: To obtain a reliable evaluation of these post abnormalities patients should be evaluated with adequate exposures of the affected body parts. As [00:17:00] in, Carlo Alberto said before , the degrees of spinal flexion should be calculated in the coronal and the sagittal plane, according to the currently accepted evaluation methods, and I'm talking about, for example, the very useful app, NeuroPostureApp, and we recommend to calculate posture degree by analyzing photographs using this app it's a freeware software based measurements. You can also use for example, the wall goniometer or the smartphone, but you have to be very careful because possible underestimations of the degree of a trunk flexion should be considered in these cases. And another important point of this work is that about the measurements is that these postural abnormalities should be evaluated, not only static in condition, but also in dynamic because, often these postural abnormalities get worse during dynamic condition. And about this [00:18:00] point, we have planned a new study with this task force to evaluate these patients during static and dynamic condition in order to quantify and say that it's important to evaluate in dynamic condition. The first point is the proposed criteria can help to overcome the impressive heterogeneity on postural abnormality prevalence data that you find in literature. For example, the percentage of Pisa syndrome ranges from 2 to 9%, camptocormia from 3 to 70%, antecollis from 5% and 9%. And finally a uniformity in nosology and cut-values with the novelty ,As Carlo Alberto said before, of considering the mild form of postural abnormalities may facilitate the research on treatment and prevention program because prevention program are the most important part of our work. [00:19:00] So this is the most important part, prevention programs. 

[00:19:04] Dr. Hugo Morales: Thank you, Dr. Geroin, I think that's very sort of appealing just to start to evaluate this patient with this new cut-off values and understand better the initial manifestations progression of these axial postural abnormalities. The best strategies to prevent progression or reduce disability because of this. 

I would like to thank again our podcast guests for today's interview, Dr. Tinazzi, Dr. Alberto Artusi, and Dr. Christian Geroin and also to recommend our audience to read the paper “Task Force Consensus on Nosology and Cut-Off Values for Axial Postural Abnormalities in Parkinsonism” that was recently published on Movement Disorders Clinical Practice Journal.