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Pelvic Function Research Article by Rachel France

Posted by: Emma on: 03/07/2016

Category: pilates

Pelvic Function Research Papers Simplified

Now those of you who have been in a classroom with me will probably have heard me say at some point that I am a slow learner, that its takes me a while to work things out and that I am not 'naturally' bright nor academic (as my old school teachers may have mentioned a few times). If I have a technical question in my head it takes me a while to find a way of making sense of it. Like many of us right!?

Well I've had a question or 2 challenging me for a while and so having spent some months reading research papers about LLD, pelvic function, sacro iliac joint (SIJ) pain, symmetry of the pelvis, methods of measuring LLD etc, as a Biomechanics Coach™ I found it interesting that so few of the papers I found related simply to function, or how to correct it. Almost all the papers were connected to ‘clinical’ findings or ‘medical’ issues and ‘symptoms’.

I mean why on earth would you research something that isn't a problem?

Well to prevent the problem maybe?!

As Biomechanics Coaches™ we assess and prepare our clients to move better to avoid symptoms and clinical problems, pathology and pain. This preparation for movement is vital considering the lives we now lead amongst technology and equipment etc that make our lives ‘easier’, less effort, quicker and in fact less active than ever.

My project was because I wanted to understand the relevance of a leg length discrepancy (LLD) based on as much evidence as possible.

I found papers that discussed pelvic position, structural leg length discrepancy (SLLD) even functional leg length discrepancy (FLLD) and some looked at whether the LLD affected LBP

My question was - Does evidence tell us that a LLD affect low back health? and is there a difference between SLLD and FLLD and their influence on back health?


SLLD - or structural leg length discrepancy.

An example of this is the individuals femurs are genetically different in length therefore creating a structural difference that cannot be changed without surgical intervention.

Another example might be someone who has broken a bone and therefore now has a structural difference caused by the trauma

FLLD - or functional leg length discrepancy.

This is discussed often in research papers and describes a twisted or rotated pelvis, around the SIJ which creates the appearance of a LLD. Should the dysfunction causing the rotation or twist be removed the LLD can also disappear.

How do we know if we have either an SLLD or FLLD?

Ii is m understanding that, in podiatry, if there is a LLD that is less than 11mm it is classed as ‘insignificant’

Also in the research it almost always seems to be assumed there has a to be a clinical significance if there is a LLD present.

While in my very limited experience as a Biomechanics Coach™ most LLD (and they are more often than not UNDER 11mm) are FLLD that are NOT clinical and can be addressed/ corrected with simple exercises. The presence of a FLLD seems to coincide with the degree of low back pain they experience.

So WHY is this?

Let me give you the low down about what I found out:

Starting with the pelvis - there is evidence from Rose McDonalds work, when she was head physio at Crystal palace athletics club, that the hips/pelvis are at least partly responsible for 60% of lower limb injuries from a biomechanical point of view.

Also in my 10 years experience of using pelvic muscle anti spasms, particularly on the hip rotators, flexors and extensors, it has has had a huge impact on all of my clients, in particular their appearance of a FLLD.

Their ROM improves, pain is reduced, strength has increased, they report feeling more stable and overall feel they move better.

Now there are groups and individuals out there who still challenge everything, which as you already know from previous Juicemails I encourage my learners to do, and they have challenged me on my methods and the evidence based programme I use.

Do you know what.... it is the times when I am confronted and challenged that I grow an expand the most. When at my most uncomfortable is when I learn and absorb information best. When someone questions the very core of what I do in my practice and the method I teach in the academy, the thing I am most passionate about.

This happens sometimes and it happened recently and I am thankful for the challenge because it took me on a little journey of exploration through reams and reams of research papers and books and conversations with peers and mentors and colleagues and what fun i have had in the ‘growth zone’!

Do you know where I ended up?

Apart form writing this for you guys of course….

Well after reading complex equations, difficult language, conflicting evidence, fascinating arguments, strange opinions and lengthy articles I ended up with


Do you remember the SO WHAT article?

Well yes thats where I ended up asking myself SO WHAT?

What am I trying to achieve with my clients?


Hang on….what AM I achieving with my clients??

Their ROM improves, pain is reduced, strength has increased, they report feeling more stable and overall feel they move better.

So no matter what the research states, no matter what the trolls say, no matter what challenges you, if your client feels better, moves better, experiences less pain and you have some objectivity to measuring improvements - SO WHAT?

So please feel free to read away to your hearts content some really interesting papers listed here but ultimately does your input get the desired output?

Rachel France DipITS DipBE QTLS IC IBAM

Managing Director Biomechanics Education Ltd


Allyn.L e al, 1984, Leg length discrepancy assessment:accuracy & precision of 5 clinical method of evaluation

Arumugam et al (2012) Effects of eternal pelvic compression o form closure, force closure & neuromotor control of the limbo-pelvic spine.

Beattie et al (1990) Validity of derived measurements of leg length differences obtained by use of tape measure

Calvilla et al, 2000, Anatomy and pathophysiology of the SIJ

Cibulka (2002) Understanding SIJ movement as a guide to the management of a patient with unilateral low back pain

Connell (2007) A case study report - concept of assessment & treatments of anterior knee pain related to altered spine & pelvic biomechanics

Cooperstein, Lew (2009) The relationship between pelvic torsion & anatomical leg length inequality

Cummings et al (1993) The effects of imposed leg length difference on bone pelvic asymmetry

Cusi (2009) Paradigm for assessment & treatment of SIJ mechanical dysfunction

Dillen et al (2008) Hip rotation ROM in people with & without LBP who participate in rotation related sports.

DonTigny (1985) Function & pathomechanics of the SIJ

DonTigny (1989) Anterior dysfunction of the SIJ as major factor in etiology of idiopathic Low Back Pain syndrome

Duff et al (2000) The reliability & validity of the ‘tape’ & ‘block’ methods for assessing anatomical leg length discrepancy.

Forst et al (2005) The SIJ; Anatomy, physiology & clinical significance

Fryer (2004) Methods used by members of the Australian osteopathic professional to assess the SIJ

Fryer (2005) Factors affecting the inter-examiner & inter-examiner reliability for supine medial malleoli asymmetry

Goode et al (2008) 3 dimensional movements of the SIJ

Gurney (2001) Leg Length Discrepancy

Hungerford et al (2003) Evidence altered lumbo-pelvic muscle recruitment in the presence of SIJ pain

Jacob, Kissling (1994) The mobility of the SIJ’s in healthy volunteers between 20-50yrs

Kasis et al (2008) External fixator assisted acute shortening wit internal fixation for leg length discrepancy after retool hip replacement

Kiapour et al (2012) Relationship between limb length discrepancy & load distribution across SIJ

Krawiec et al (2003) Static innominate asymmetry & leg length discrepancy in asymptomatic collegiate athletes

McCaw, Bates (1991) Biomechanical implications of mild leg length discrepancy

McGrath (2004) Clinical considerations of SIJ anatomy; A review of function, motion & pain

Middleton-Duff et al 2000, The reliability and validity of the `Tape' and `Block' methods for assessing anatomical leg-length discrepancy, Harcourt Publishers Ltd

Pel et all (2008) Biomechanical analysis of reducing SIJ shear load by optimisation of pelvic muscle & ligament forces

Preece et al (2008) Variation in pelvic morphology may prevent the identification of anterior

pelvic tilt

Richardson et al (2001) The relation between the TVA, SIJ mechanics & low back pain

Sabharwal, Kumar (2008) Method of assessing leg length discrepancy

Santaguida, McGill (1994) The psoas major muscle; a 3 dimensional geometric study

Sturesson et al (1999) A radiostereometric analysis of movements of the SIJ’s during standing hip flexion

Suter et al (1999) Decrease in quadricep inhibition after SIJ manipulation in patients with anterior knee pain

Takasaki et al (2008) The influence is increasing SIJ closure on the hip & lumbar spine extensor muscle firing pattern

Van Der Wurff et al (2006) A multitest regimen of pain provocation tests as an aim to reduce unnecessary minimally invasive SIJ procedures.

Van Der Wurff et al (2000) Clinical tests of the SIJ

Vleeming et al, 2003, Stabilisation of the SIJ in vivo: verifications of muscular contribution to force closure of the pelvic

Vleeming et al (2012) The SIJ: An overview of its anatomy, function & potential clinical implications

Winderden et al (2003) Stabilization of SIJ in vivo

Woerman et al (1984) Leg length discrepancy assessment; Accuracy & precision in 5 clinical methods of evaluation

Woodfield et al (2011) Interexaminer reliability of supine leg checks for discriminating leg length discrepancy

Wylde et al (2008) Prevalence & functional impact of patient perceived leg length discrepancy after hip replacement


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