Posture, acture and balance

Chapter contents

Kuchera & Kuchera (1997) define the topic very simply: ‘Posture is distribution of body mass in relation to gravity over a base of support. The base of support includes all structures from the feet to the base of the skull’. They add that the efficiency with which weight is distributed over the base of support depends on the levels of energy needed to maintain equilibrium (homeostasis), as well as on the status of the musculoligamentous structures of the body. These factors – weight distribution, energy availability and musculoligamentous condition – interact with the (usually) multiple adaptations and compensations that take place below the base of the skull, all of which can influence the visual and balance functions of the body.

This chapter focuses on static as well as active postural features and how to assess some of these. Implicit in the evaluation of posture (and of gait, which forms the focal point of Chapter 3) is the way in which the body achieves and maintains its sense of balance, equilibrium and poise.

The CNS and brain receive an unceasing flood of data deriving from reporting stations. How this information is processed, and the instructions that flow to the tissues as a result, form the focus of the latter segment of this chapter. These issues are also more deeply examined in Volume 1, Chapter 3.

Key postural influences

Korr (1970) called the musculoskeletal system the ‘primary machinery of life’. By this he meant the functioning, ambulant, active features of the body, through which humans usually express themselves by doing, creating and generally functioning in the world, while interacting with society, the environment and with others. Korr distinguishes this ‘primary machinery of life’ (the locomotor system, the musculoskeletal system), in all its dynamic complexity, from the more (medically) glamorous ‘vital organs’, all of which subserve it, and allow it to act out the processes of being alive. Influences as diverse as gravity, emotion, visual integrity, central (brain) processing factors and the adaptations, which emerge as a result of the wear and tear of life, all influence the way this biomechanical marvel is carried and employed in space.

A number of Kuchera’s insights are considered in this chapter.

Latey (1996) discusses the patient’s presentation (or ‘image’) posture compared with the residual posture (as evidenced by palpation when he or she is resting quietly). He also draws attention to patterns of neuromuscular ‘tension’, which create postural modifications and which emerge from long-held emotional states, such as anxiety and depression. (Image posture and other Latey concepts are discussed later in this chapter.)

Gagey & Gentaz (1996) offer insights as to neural input into the fine postural system and central integration of the virtually constant flow of information deriving from the eyes, the vestibular apparatus, the feet, etc. (The findings of Gagey & Gentaz in relation to proprioceptive input in particular, are expanded on later in this chapter.)

Janda (1991) has shown that a central source of muscular imbalance (increased tension, for example, which inevitably results in postural changes) may result from limbic system dysfunction.

The efficiency of postural balance depends (among other factors) on three sets of information reaching the brain for processing: visual, proprioceptive and vestibular. We automatically regulate how much importance to give one of these sources of information, over the others, when distorted data is being received – for example, when standing on an unstable surface that provides inaccurate visual information. Assessment as to visual efficiency can be achieved by testing balance with the eyes closed. (Redfern et al 2007).

Redfern et al (2007) have also demonstrated that individuals with anxiety related disorders are most dependent on vision for balance, suggesting that reduced anxiety levels, potentially achievable via enhanced breathing patterns, relaxation methods, counseling or activities such as Tai Chi – might significantly improve balance (Gatts & Woollacott 2007).

There appears to be a significant connection between cervical dysfunction, particularly involving the suboccipital extensor muscles (Gosselin et al 2004), and conditions such as osteoarthritis of the cervical spine (Boucher et al 2008), and disturbed balance.

A variety of health conditions ranging from type 2 diabetes (with its tendency towards peripheral neuropathy) (Centomo et al 2007), and chronic low back pain (Lafond et al 2009), will affect balance negatively.

Vleeming et al (1997, 2007) discuss ‘wear and tear’ – or ‘postural decay’ as they describe it – as the battle against gravity is slowly lost over a lifetime.

Is there an ideal posture?

Kuchera & Kuchera (1997) describe what they see as ‘optimal posture’.

This succinct expression of postural reality highlights the fact that there is hardly ever an example of a ‘picture-perfect’ postural state; however, there can be a well-compensated mechanism that, despite asymmetry and adaptations, functions as close to optimally as possible. An aim to achieve well-compensated function is a realistic ideal and should be a principal clinical goal. To achieve that goal requires recognition of the global interaction between local features, functions and influences. Unless an integrated account is taken of emotional states, gravitational influences, proprioceptive and other neural inputs, inborn characteristics (short leg, etc.), as well as habitual patterns of use (upper chest breathing, for example) and wear and tear, whatever postural and functional anomalies are observed will remain signs of ‘something’ abnormal happening, of ongoing compensation or adaptation. The chance of fully understanding just what the ‘something’ is will be remote.

Gravitational influences and muscles

Kuchera (1997) cites Janda (1986) when he connects gravitational strain with changes of muscle function and structure, which lead predictably to observable postural modifications and functional limitations.

‘Postural muscles, structurally adapted to resist prolonged gravitational stress, generally resist fatigue. When overly stressed, however, these same postural muscles become irritable, tight, shortened. The antagonists to these postural muscles (most usually phasic muscles) demonstrate inhibitory characteristics described as ‘pseudoparesis’ (a functional, non-organic, weakness) or ‘myofascial trigger points with weakness’ when they are stressed.’

See Box 2.1 as well as Volume 1, Chapter 2 for a discussion of the postural and phasic muscles.

Richardson et al (1999) have published numerous study results showing which muscles are most involved in spinal postural stabilization:

Additionally, Hodges (1999) highlights the importance of the abdominal muscles as well as, perhaps surprisingly, the diaphragm in postural control. In a study (Hodges et al 1997) which measured activity of both the costal diaphragm and the crural portion of the diaphragm, as well as transversus abdominis, it was found that contraction occurred (in all these structures) when spinal stabilization was required (in this instance during shoulder flexion).


There is certainly no absolute agreement on which muscles provide ‘core stability’ (Figure 2.1). For example Grenier & McGill (2007), ask the question:

To answer the question they used electromyography and spine kinematic recordings, during an abdominal brace, and a hollow, while supporting either a bilateral or asymmetric weight in the hand, to demonstrate that:

Naturally, other muscles are also involved in stabilization and antigravity tasks but these examples exemplify the complex interactions that occur constantly, whenever the need for core stability occurs.

The involvement of the diaphragm in postural stabilization suggests that situations might easily occur where contradictory demands are evident – for example, where postural stabilizing control is required at the same time that respiratory functions create demands for diaphragmatic movement (shoveling snow, for example). Richardson et al (1999) state: ‘This is an area of ongoing research, but must involve eccentric/concentric phases of activation of the diaphragm.’


Observable changes such as those illustrated in Figure 2.2A emerge through overuse, misuse, abuse and disuse of the postural system and demonstrate common dysfunctional postural patterns.

‘Anterior crossed pelvic pattern’ (see Fig. 2.2C)

Characterized by:

Hypoactivity/lengthened muscles:

Hyperactivity/adaptive shortened muscles:

Flexor muscles tend to dominate leading to:

Observation and assessment, as described in this text, can help to identify these common patterns.

The above examples clearly show value of the expansion of the work of one author by others. However, with the additional value may also come some inherent risks of degradation or potential confusion. The use of terms postural muscle and phasic muscle is a prime example and requires some elaboration. Box 2.1 lists some of the postural and phasic muscles, any of which (when stressed) may significantly contribute to postural misalignment. Box 2.2, as well as the following text, offers discussion of some of the confusing terms used to categorize these muscle types. An international nomenclature standard for postural terminology as well as for symbols used to record findings needs to be developed, published and adopted in order to avoid the confusion that develops when numerous groups each develop their own style.

Box 2.2 The muscle debate

Norris (2000) explains his perspective on the use of terms such as postural, phasic, stabilizer, mobilizer, etc. in categorizing muscles.

The terms postural and phasic used by Jull and Janda (1987) can be misleading. In their categorization, the hamstring muscles are placed in the postural grouping while the gluteals are placed in the phasic grouping. The reaction described for these muscles is that the postural group (represented by the hamstrings in this case) tend to tighten, are biarticular, have a lower irritability threshold and a tendency to develop trigger points. This type of action would suggest a phasic (as opposed to tonic) response and is typical of a muscle used to develop power and speed in sport for example, a task carried out by the hamstrings. The so-called ‘phasic group’ is said to lengthen, weaken and be uniarticular, a description perhaps better suited to the characteristics of a muscle used for postural holding. The description of the muscle responses described by Jull and Janda (1987) is accurate, but the terms postural and phasic do not seem to adequately describe the groupings. Although fiber type has been used as one factor to categorize muscles, its use clinically is limited as an invasive technique is required. It is therefore the functional characteristics of the muscle, which is of more use to the clinician. Stabilizing muscles show a tendency to laxity and an inability to maintain a contraction (endurance) at full inner range. Mobilizing muscles show a tendency to tightness through increased resting tone. The increased resting tone of the muscle leads to or co-exists with an inclination for preferential recruitment where the tight muscle tends to dominate a movement. The stabilizing muscle in parallel shows a tendency to reduced recruitment or inhibition as a result of pain or joint distension.

Norris continues:

A further categorization of muscles has been used by Bergmark (1989) and expanded by Richardson et al (1999). They have used the nomenclature of local (central) and global (guy rope) muscles, the latter being compared to the ropes holding the mast of a ship. The central muscles are those that are deep or have deep portions attaching to the lumbar spine. These muscles are seen as capable of controlling the stiffness (resistance to bending) of the spine and of influencing intervertebral alignment. The global category includes larger more superficial muscles. Global muscles include the anterior portion of the internal oblique, the external oblique, the rectus abdominis, the lateral fibers of the quadratus lumborum and the more lateral portions of the erector spinae. …The local categorization includes the multifidus, intertransversarii, interspinales, transversus abdominis, the posterior portion of the internal oblique, the medial fibers of quadratus lumborum and the more central portion of the erector spinae. The global system moves the lumbar spine, but also balances/accommodates the forces imposed by an object acting on the spine.

Comerford & Mottram (2001a, b) have further refined the debate as to classification of muscles.

Local stabilizers – are deep, monoarticular, maintain stability of joints in all ranges of movement; using local muscle stiffness to control excessive motion, particularly in neutral positions where capsular and ligamentous support is minimal. Local stabilizers include the deeper layer muscles which attach segmentally (i.e. spinally such as multifidi), and which increase activity before action to offer protection and support. Dysfunctionally there may be loss of efficient firing sequencing, with a tendency toward inhibition and loss of segmental control (for example, deep neck flexors). These muscles equate (more or less) with Janda’s phasic muscles. ‘Dysfunction of local stability muscles is due to alteration of normal motor recruitment contributing to a loss of segmental control.’ Therapeutic interventions should encourage and facilitate tonic activation and strength.

Global stabilizers – are also monoarticular, more superficial than the local stabilizers, and lacking in segmental (spinal) attachments, inserting rather on the thorax or pelvis; they generate force and control ranges of motion orientation of which may be biased with functions relating torque; when dysfunctional there is likely to be reduced control of movement (for example, transversus abdominis). These equate (more or less) with Janda’s phasic muscles. ‘Dysfunction of the global stability muscles is due to an increase in functional muscle length or diminished low threshold recruitment.’ Therapeutic interventions should encourage and facilitate tonic activation and strength.

Mobilizers are biarticular or multiarticular, superficial, provide long levers and are structured for speed and large movements. These equate with the postural muscles of Janda (for example, psoas). Dysfunctional patterns result in shortening (‘loss of myofascial extensibility’) and react to pain and pathology with spasm. ‘Dysfunction of the global mobility muscles is due to loss of functional muscle extensibility or overactive low threshold activity.’ Therapeutic interventions should encourage mobilization and lengthening.

Assessment methods, which include evaluation of relative strength, length and appropriate firing sequence, can rapidly suggest patterns of dysfunction within particular muscle classifications, whichever designations or labels (descriptors) are assigned to them.

Note: The reader will recognize the potential for confusion unless a standard set of descriptors is used. While acknowledging the importance of developments in muscle classification and characterization, we have chosen to employ the Jull & Janda ‘postural’ and ‘phasic’ categorizations, as used in Volume 1.

Muscle categorizations

It is possible (to some degree) to categorize muscles by their primary functions, these being to maintain the body in a stable, posturally balanced state in its constant struggle with gravity, as well as providing the capacity for movement and action. Not only is the categorization of muscles useful when attempting to determine causes of dysfunction and in formulating a treatment and/or rehabilitation plan, it is also practical since there is a degree of predictability in the performance (and eventual pathophysiological response leading to dysfunction) of particular muscles when they are under stress (overuse, misuse, abuse, disuse). For instance, certain muscles tend to become weak when stressed (inhibited, hypomyotonic, ‘pseudoparetic’, hypotonic) while others will tend to develop a higher degree of tension (hypermyotonia, ‘tight’, hypertonic) and will ultimately shorten (Norris 2000).

Janda’s (1986) classification of muscles as ‘postural’ and ‘phasic’ (see Box 2.1) states that postural muscles become hypertonic (and subsequently shortened) in response to stress whereas phasic muscles become inhibited (‘weakened’, displaying what he terms ‘pseudo-paresis’) when similarly stressed. Janda’s classification of muscles has been challenged by some (for example, Norris 2000) who prefer descriptors such as ‘stabilizers’ and ‘mobilizers’ (where, somewhat confusingly, stabilizers are equated with the muscles which Janda classifies as phasic). Additional descriptors include ‘global’ and ‘local’, ‘superficial’ and ‘deep’, as well as monoarticular and polyarticular. Comerford & Mottram (2001a,b) have further refined muscle classification by defining particular muscles as local stabilizers, global stabilizers and global mobilizers.

While fully aware of the value of this debate regarding the pathophysiology of musculoskeletal structures and its potential to transform ideas and concepts, we have chosen to use Janda’s (1986, Jull & Janda 1987) descriptors (i.e. postural/phasic), which are (at this time) more widely familiar to readers and which are, as a result, probably less confusing. This decision to use Janda’s descriptors is not meant to deny the validity of other ways of classifying muscles nor to discourage of the expansion of Janda’s ideas by Norris and others. It is the authors’ belief that ultimately the names ascribed to the processes and structures involved are of less importance than the basic fact that, in response to stress (overuse, misuse, abuse, disuse), particular muscles have a tendency toward shortening – whatever the name or category given to them – while others have a tendency toward inhibition, weakness and sometimes lengthening. As this debate continues, it will be interesting to see what emerges when adequate research relating to muscle types, recruitment sequences and other details involving the pathophysiological responses of different muscles to the stresses of life provides critical data relevant to the ongoing controversy (Bullock-Saxton et al 2000).

Necessary assessments

Evaluating muscular imbalance and dysfunction relating to posture (in general) and antigravity tasks (in particular) may involve a variety of assessment methods that examine for the following elements. Assessment methods are described in later sections of this text, where appropriate.

Static postural images

While ‘perfect posture’ is seldom seen in a clinical setting, an understanding of a standard or ‘ideal’ alignment is necessary in order to know when variations exist. Kendall et al (1993) note:

Kendall et al offer specific and in-depth discussions as well as illustrations of ideal plumb line alignment, which parallel the concepts taught in this chapter.

Petty (2006) has listed a variety of static postural patterns. These include the ‘ideal’ posture as described by Kendall et al (1993) and include:

These static postural pictures certainly offer clues as to patterns of imbalance – which muscles are likely to test as weak and which as tight, for example. They are, however, simply ‘snapshots’ of non-active structures (apart from their antigravity functions involved in being upright). The unbalanced image does not explain why the imbalances exist or how well the individual is adapting to the changes involved. When faced with structures that are apparently ‘weak’ or ‘tight’, it is of clinical importance to consider ‘Why is this happening?’.

Is it due to overuse? The patient’s history and descriptions of daily habits of use should provide information regarding this possibility.

Or could there be reflexive activity due to joint blockage or other influences (such as viscerosomatic reflexes)? Careful evaluation of the history and symptoms, along with palpation and assessment, should provide evidence of joint restrictions and/or the likelihood of viscerosomatic influences.

Or are trigger points active in these muscles or their synergists or antagonists? Careful evaluation of the symptom picture as well as neuromuscular evaluation and palpation for active triggers may confirm such a possibility.

Or are neurological factors involved? Clinical evaluation, or referral to an appropriate practitioner may confirm or rule out such possibilities.

Or is there a structural asymmetry (short leg, etc.) for which the soft tissue is compensating? Careful observation, palpation and assessment should offer answers to this question.

Or is this apparently unbalanced adaptation caused by some ‘tight’ and some ‘loose’ musculature – the very best solution the body can find for habitual patterns of use (occupational or sporting demands, for example) or by congenital or acquired changes (short leg, arthritic change, etc.), which should be understood, rather than interfered with. Therapeutic solutions in such instances are often best addressed to the habits of use, rather than the adaptive changes.

Despite not in itself providing clear answers to such questions, static postural assessment may provide indications that suggest the focus of further investigation. Static assessment forms an important part of postural evaluation and analysis and assists in the training and refining of vital observational skills.

Tools of postural assessment

Computerized assessment methods

Computerized methods of postural assessment have also been developed, ranging from simple digital images to interfacing computer programs with information-gathering ‘wands’ that analyze static standing posture by placing the tip of the wand at various anatomical landmarks. The wand inputs data into the computer, which records the data and prints out various written and illustrated data sheets. While this equipment is fairly expensive, it is also highly efficient as it records the data with literally a touch of the wand and produces printed reports at the touch of a button, with very little keyboard input required from the practitioner. The primary drawback is its relatively high cost. It is also noted that human error in placement of the wand can distort findings and produce inaccurate information.

Sophisticated computerized gait analysis programs and equipment have also emerged which gather information from electrodes attached to various body parts (e.g. weight-bearing points on the soles of the feet) and analyze the information that floods into the computer. One advantage of computerized methods is that the computer can quickly analyze data from several assessments of the same person, or assessments from different people, to compare findings.

Digital videography, with analyzing software, also offers a sophisticated interpretation of findings. Multiple computer screen images can be viewed simultaneously, whether these are from several views at one session or from several sessions. Pretreatment and post-treatment views can be overlaid to emphasize changes in structural alignment deriving from the therapeutic intervention. An image of ‘before’ and ‘after’ standing or walking can be viewed side by side and can provide a powerful reinforcement for the patient of the value of treatment and rehabilitation strategies. See also discussion of Linn’s work (2000) with computerized images on p. 43.

These types of computerized programs, combined with voice-activated software, may simplify the recording process of patient examination so that notation of findings and record keeping are not only more easily accomplished but are also more accurate and clinically valuable. Additionally, such recordings may offer the advantage of being able to be viewed (over the web) by experts in distant locations (either in real time or moments after they are taken) while the patient is still present and available for further testing. Such a ‘second opinion’ takes on a different dimension as travel and other costs are decreased while availability of the ‘expert’ may significantly increase – from his or her own office many miles away. The use of such technology in teaching settings, via the web, is self-evident. Tutors and students can potentially interact as they evaluate clinical evidence while being geographically separated.

Basic postural assessment

Whether termed ‘postural assessment’ or ‘postural analysis’, the step-by-step procedure of looking at the structural landmarks of the body, both in weight bearing and non-weight bearing positions provides potentially clinically relevant information to the practitioner. The following protocol offers first a weight-bearing assessment and then a supine assessment of the non-weight bearing structures.

The assessment may usefully begin as the person enters the reception area or treatment room or even as he is walking across the parking lot. Habits of use will be more obvious when the person is not aware he is being observed, such as how he carries objects, perhaps slung over a shoulder, sits in a slump position or walks with his head forward of the body. Additionally, the ‘examination’ of commonly carried objects, such as a purse or brief case, might reveal excessive weight being borne by a particular arm, resulting in excessive stress for which adaptive compensations are being made.

Once the session begins, the individual being examined should be as unclothed as is deemed possible and appropriate, or dressed in form-hugging attire (such as leotards, tights or biker’s shorts), so that key features are not masked by clothing. It should be noted that horizontal or vertical patterns printed on the clothing may distort perceptions when the fabric is pulled even slightly askew, therefore making solid color (or white) clothing a better choice for assessment. Patient examination gowns do not work well as they are loose fitting and skeletal details are not distinct. Palpation through heavier clothing, such as jeans, dress, pants or jackets, is difficult. The practitioner may eventually develop the skill to assess much of the body’s alignment even when the person is more fully clothed, but much more detail will be seen if clothing is limited and form fitting. The temperature of the room should be comfortable, especially of concern if the person is relatively unclothed.

It should be borne in mind that most people will feel fairly self-conscious with the process of being methodically examined in this manner and will most probably present their best ‘image’ posture (see discussion of Latey’s work later in this chapter), especially at the onset of the session. It may, therefore, prove beneficial to provide a distraction at the outset of the assessment, such as having the person march in place while swinging his arms (eyes may be open or closed) or turning the head left and right, then stop and relax.

Although the movements are not actually for assessment purposes (and are not to be confused with stepping tests discussed on p. 48), the diversion of ‘doing something’ often distracts the patient sufficiently to allow a more relaxed posture to manifest. Foot positioning, such as occurs with habitual lateral rotation of the leg, often becomes more obvious after such movements. It should also be noted if, upon stopping, he then pulls the body ‘up’ into a better alignment, which might represent a conscious effort to ‘look good’ for the assessment.

Standing postural assessment (Fig. 2.7)

The person should be relaxed and standing barefoot on level flooring. There should be ample space to allow the practitioner to move without crowding the person or needing to move him. The arms of the person being examined should hang comfortably at the sides, and the feet should be placed in a position that feels comfortable.

Observations should initially be made with the patient in a ‘comfortable’ standing position (i.e. the habitual way he stands) and should then be repeated with the feet in neutral alignment, which is approximately under the glenohumeral joints, and tracking forward with no more than 10° of lateral rotation. The first position (that of ‘habitual’ comfort) often displays compensation patterns, such as forward placement and lateral rotation of the ‘long’ leg, while the second position, with the feet in neutral, may accentuate postural distortions, such as an elevated shoulder or hip, or head tilt.

At first the practitioner should stand in front, at a distance of 10–15 feet (if space allows). Observation at this distance gives an overall impression of alignment and often reveals ‘global’ compensations that are masked when the practitioner moves closer. Head tilt, shoulder height differential, pelvic tilt and the appearance of carrying more body weight on one leg than the other are all examples of what may be seen from a distance.

A coronal viewpoint from a distance may reveal forward-leaning posture, locked knees (genu recurvatum), forward head position or accentuated or flattened spinal curves. If a plumb line is utilized, these faulty positions may be even more obvious and easily seen in documentary imaging (by Polaroid®, digital camera or video).

The practitioner should then move to within a few feet, where greater detail will become apparent, particularly of cranial structures. The practitioner’s hand can palpate bony landmarks so that a more precise comparison may be made and recorded. The following observations are suggested as a basis for assessing how much the body has deviated from the ‘ideal’ posture. Also included are some of the possible causes that may warrant further investigation.

Anterior view (Fig. 2.9)

Is the head held erect or does it tilt to one side or the other?

Are the earlobes level?

Does one ear, or do both ears, flair excessively from the head?

Are the eyebrows level?

Box 2.3 Cranial observation and assessment exercise (see Fig. 2.8)

Observe the face of a patient for symmetry. Marked asymmetry may result from:

Palpation of the temporal region, where the great wings of the sphenoid are located, provides evidence of symmetry or lack of it. If asymmetry exists between the positions of the great wings, the following should be noted on the high great wing side.

General observation commonly reveals a range of asymmetries in the facial features, which may be interpreted as indicating underlying patterns of imbalance at the sutures of the skull, usually involving the intracranial fascial structures (reciprocal tension membranes). For a greater understanding of the underlying imbalances and their significance globally, texts by Milne (1995), Chaitow (2005) and Upledger & Vredevoogd (1983) are recommended. Features for which to observe include:

Are the eyes level and of similar dimensions?

Does palpation and/or observation of the cranium demonstrate any asymmetrical features?

Is the nose straight and centered, with symmetrical nasal apertures?

Is the central contact of the two upper central incisors of the maxilla centered under the midline of the nose?

Is the central contact of the two lower central incisors of the mandible centered under the midline of the nose?

Does the mid-line of the mandible track in a straight and smooth vertical line as the mouth is opened and closed?

Is the distance between the bottom of the earlobe and the top of the shoulder the same on each side?

Is the muscular mass of either or both upper portion of trapezius excessive (as in ‘gothic shoulders’) or are they both balanced and of normal proportions?

Are the acromioclavicular joints level with each other?

(The practitioner’s index fingers placed one on each joint will assist in making this more apparent.)

Do the arms hang comfortably at the sides with the shoulders placed in neutral position (the tendon of the long head of the biceps facing directly laterally) with no apparent medial or lateral rotation of the humerus?

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Dec 11, 2016 | Posted by in NEUROLOGY | Comments Off on Posture, acture and balance
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