SI Joint Mechanics in Manual Therapy: Relevance, Please?

In a separate post Publishing in Science: Are Industry Standards Serving Researchers, Clinicians and Science? Jason Silvernail and I outline some of the perceived cons of the current publishing paradigm. We describe our experience writing a letter to the editor of Manual Therapy. In the end, our goal was, and is, to express our interpretation of the study Inter-tester Reliability of Non-invasive Technique for Innominate Motion by Adhia et al, including it’s relevance to the context of the current scientific research on the sacroilliac/pelvic region, pain, manual therapy, and modern clinical practice. We hoped, and continue to hope, to facilitate scientific discussion and discourse surrounding the topic.

Recently, others in the blogsphere have written about the assessment and treatment of the SI joint including Mike Reinold Assessing the SI Joint: The Best Tests. John Childs from Evidence in Motion, in the piece A blast from the past highlights how some continue to cling to old views of pain and “SI dysfunction.”

We feel our original, longer piece (which was denied prior to review) summarizes the issues of assessment and treatment of the SI/pelvis region quite well, while connecting various scientific and clinical issues. We cannot share the piece that is currently in press for Manual Therapy [Ridgeway K, Silvernail J. Innominate 3D motion modeling: Biomechanically interesting, but clinically irrelevant. Manual Therapy (2012). doi: 10.1016/j.math.2012.02.017] as they own the copyright. Although, we will provide the link when it is electronically published. Yet, we can share a completely different version of our letter that we were working on before we modified it for length. To be clear the version below is not the letter that is currently in press.

Here is our best reply, in full, to Adhia et al:

We would like to thank Adhia and colleagues for their contribution to the literature regarding the non-invasive modeling of Sacro-Iliac joint (SIJ) motion. This study is interesting from a biomechanical perspective of the inter- and intra-rater reliability of measuring innominate motion via non-invasive palpation based measurements. However, in our opinion, this study has limited relevance to practicing clinicians and to the overall science and practice of manual therapy. The authors conclude “The results support clinical and research utility of this technique for non-invasive kinematic evaluation of SIJ motion for this population. Further research on the use of this palpation digitization technique in symptomatic population is warranted.” This seems to be a rather large logical leap given the results of their investigation and other data in the literature on the manual therapy assessment and treatment of the SIJ and pelvis region. We feel the clinical utility of SIJ palpatory movement testing has not been demonstrated by other research and we struggle to understand how such an assessment tool assists in evaluation, clinical assessment, or treatment with manual or physical therapy.

Movement of the SIJ appears to be very small, highly variable, and difficult to measure. Although undoubtedly complex, movement and translation of the SIJ is estimated to be small and variable between individuals (Harrison 1997, Goode 2008) while variation in anatomy exists even within individuals (Cohen 2005). Historically, SIJ dysfunction and pain has been “diagnosed” clinically via palpation-based tests aimed to identify hypo/hypermobility as well as asymmetry in anatomical landmarks. (Arab 2009)  From a basic anatomical and biomechanical plausibility perspective, measuring this motion and connecting it to a diagnostic process may be futile given the small amount of motion that occurs at the SIJ relative to other joints and the anatomical variation between and within individuals.

The evidence from diagnostic and therapeutic studies of the SIJ and pelvis area doesn’t suggest a clinically useful role for SIJ diagnosis via palpatory movement. A growing body of research indicates that positional palpation based testing in the spine and pelvis region, including the sacroiliac joints, is unreliable within and between examiners (Goode 2008, Laslett 2008). Investigations that do find some measure of reliability for testing have wide confidence intervals for their measurements, calling into question their applicability (Robinson 2007, Arab 2009). Such testing may not assist clinicians with the clinical reasoning process. Symptom provocation testing, rather than positional palpation, appears to have greater literature support, and in fact is the criteria used in guidelines produced by the International Association for the Study of Pain (IASP) (Szadek 2009). After investigating the reliability of individual provocation testing maneuvers (Laslett 1994), Laslett et al. went on to perform a high-quality double injection study (Laslett 2003) for diagnosis of SIJ related pain. This study examined the validity of provocation and movement testing in the diagnosis of a painful SIJ. In 2 separate investigations, they found that physical testing, specifically a composite of tests, aimed at provocation of symptoms was more useful in identifying individuals likely to respond to diagnostic injection, currently the most commonly-accepted “gold standard” (Laslett 2003, Laslett 2005, Laslett 2008). However, even the use of provocation testing and double injection validation according to criteria used by the International Association for the Study of Pain (IASP) does not conclusively diagnose SIJ related pain. The review by Szadek et al. illustrates some remaining issues and concerns when discussing the complexity inherent in making the diagnosis of SIJ related pain (Szadek 2009).

On the subject of clinical utility, in a developed (Flynn 2002) and subsequently validated (Childs 2004) clinical prediction rule aimed to identify a sub-group of patients who responded to an “SIJ region” thrust manipulation, no palpation based testing of the SIJ were included in the final rule. This rule was constructed via regression analysis and many palpation and movement based tests of the pelvis, lumbar spine, and SIJ region were examined, including techniques and landmarks similar to those used by Adhia et al. The final predictors of response to treatment did not include any SIJ palpatory assessments.  Certainly the failure of these investigations (both double injection diagnosis studies and manipulative treatment studies) to find positional or movement assessment of the SIJ of any clinical value raises serious issues about the validity of such assessments. Yet, it is palpatory assessment which Adhia et al investigate in their paper. Despite rigorous testing in different clinical environments, palpatory movement tests have failed to demonstrate their usefulness in helping clinicians diagnose SIJ related pain or treat pain in the SIJ and lumbo-pelvic area. We stress that overall manual palpatory examination seems to have a valid role in manual therapy in this region, but the current evidence seems to indicate that this validity is related to symptom provocation and mechanical testing (Laslett 2005, Laslett 2008) and/or an impairment-based clinical reasoning approach (Whitman 2006). Such a patient-response, impairment-based approach is quite different from the positional and movement diagnostic process advocated by Adhia et al.

Lastly, this paper seems to further perpetuate an overly biomechanical focus in the assessment, treatment, management, and understanding of pain. Moseley stated “equating pain to activity in nociceptors is seductive” (Moseley 2012), and so too is a strict biomechanically focused clinical frame of reference. This biomechanical model of pain, dysfunction, manual therapy application “target,” and treatment effect appears to have little empirical support in the current literature (including clinical trials) investigating mechanisms of action of and predictors of success with manual therapy treatment (Bialosky 2009). In light of our improved understanding of the multifactorial neurophysiology of the pain experience (Bialosky 2009, Moseley 2012 and Melzack 2001), 3D modeling of small and variable joint motion via classically unreliable, and likely invalid constructs lacks meaningful clinical utility. When taken into account with clinical trial evidence and pain neurophysiology, we do not advocate its use clinically regardless of the precision of any associated biomechanical measurements.

We are not stating that this research is flawed, or even that it is unimportant. Indeed, Adhia and colleagues should be commended on the rigor of their methods. The investigation holds immediate relevance to the non-invasive modeling and measurement of the SIJ, and there may be biomechanical studies of some value that could take advantage of this process.  However, we disagree with author’s conclusion that the investigation results are clinically applicable and we urge the readership to consider the study results in context of the current evidence – which calls into question the reliability, validity, and clinical relevance of palpatory SIJ testing and diagnosis. We are confused as to how we as clinicians could utilize the author’s technique effectively in day to clinical practice, and why, given the current state of the literature, the authors propose we should.

Kyle J. Ridgeway, DPT

  • Physical Therapist, University of Colorado Hospital, Aurora, CO
  • Physical Therapist, Panther Physical Therapy, Littleton, CO
  • Consultant, University of Colorado Anschutz Medical Campus: Physical Therapy Program, Aurora, CO


Jason Silvernail, DPT, DSc, FAAOMPT

  • Physical Therapist, US Army, El Paso TX
  • Adjunct Faculty, Army-Baylor Doctoral Fellowship in Orthopedic Manual Therapy, San Antonio TX

The authors of this letter have no financial interest to disclose. The views expressed are those of the authors alone and do not reflect the official policy or position of the Department of the Army, Department of Defense, or the US Government.


Adhia DB, Bussey MD, Mani R, Jayakaran P, Aldabe D, Milosavljevic S. Inter-tester reliability of non-invasive technique for measurement of innomiate motion. Man Ther 2012;(17):71-76

Arab HM, Abdollahi I, Joghataei MT, Golafshani Z, Kazemnejad A. Inter- and intra-examiner reliability of single and composites of selected motion palpation and pain provocation tests for the sacroiliac joint. Man Ther 2009;14(2): 213-21

Childs JD, Fritz JM, Flyn TW, Irrgang JJ, Johnson KK, Majkowski GR, Delitto A. A clinical prediction rule to identify patients with low back pain most likely to benefit from spinal manipulation: a validation study. Ann Intern Med 2004;141(12):920-8

Cohen SP. Sacroilliac Joint Pain: A Comprehensive Review of Anatomy, Diagnosis, and Treatment. Anesthesia & Analgesia 2005;101(5):1440-53

Flynn T, Fritz J, Witman J, Wainner R, Magel J, Rendeiro D, Butler B, Garber M, Allison S. A clinical prediction rule for classifying patients with low back pain who demonstrate short-term improvement with spinal manipulation. Spine 2002;27(24):2835-43

Goode A, Hegedus E, Sizer P, Brismee J, Linberg A, Cook C. Three-dimensional movements of the sacroiliac joint: A systematic review of the literature and assessment of clinical utility. J Man Manip Ther 2008;16:25–38

Harrison DE, Harrison DD, Troyanovich SJ. The sacroiliac joint: a review of anatomy and biomechanics with clinical implications. J Manipulative Physiol Ther 1997;20:607–17

Huijbregts PA. Evidence-Based Diagnosis and Treatment of the Painful Sacroilliac Joint. J Man Manip Ther 2008;16(3):153-154

Laslett. M, Williams, M. The Reliability of Selected Pain Provocation Tests for Sacoiliac Joint Pathology. Spine 1994;19(11):1243-1249

Laslett M. Aprill CN, McDonald B, Young SB. Sacroilliac Joint Pain: Validity of individual provocation tests and composites of tests. Man Ther 2005;10:207-218

Laslett M, Young SB, Aprill CN, McDonald B. Diagnosing painful sacroiliac joints: A validity study of a McKenzie evaluation and sacroiliac provocation tests. Australian Journal of Physiotherapy 2003;49:89-97

Laslett M. Evidence-based Diagnosis and Treatment of the Painful Sacroiliac Joint. J Man Manip Ther 2008;16:142-152

Melzack R. Pain and the Neuromatrix in the Brain. Journal of Dental Education 2001;65(12):1378-82

Moseley LG. Teaching people about pain: why do we keep beating around the bush? Pain Management 2012;2(1):1-3

Robinson HS, Brox JI, Robinson R, Bjelland E, Solem,S.,Telje, T. The reliability of selected motion- and pain provocation tests for the sacroiliac joint. Man Ther 2007;12(1):72-79

Szadek KM, van der Wuff P, van Tulder MW, Zuurmond WW, Perez RSGM. Diagnostic validity of criteria for sacroiliac joint pain: a systematic review. The Journal of Pain 2009; 10(4): 354-68

Whitman JM, Flynn TW, Childs JD, Wainner RS, Gill HE, Ryder MG, Garber MB, Bennet AC, Fritz JM. A Comparison Between Two Physical Therapy Treatment Programs for Patients With Lumbar Spinal Stenosis. Spine 2006;31(22):2541-2549

And, in the end “Enough is Enough”

18 Replies to “SI Joint Mechanics in Manual Therapy: Relevance, Please?”

  1. I would like to respond as a current DPT student.

    First, I really appreciate the time and effort put in by both Dr. Ridgeway and Dr. Silvernail on this particular topic of SI joint motion. I have been with many different Clinical Instructors, and have had the opportunity to learn under many PT’s, which has benefitted me tremendously. However, it can be difficult as a student to enhance your clinical reasoning when you see many, many different ways to examine, evaluate, treat, etc., and aren’t certain which strategies are best, given the current evidence.

    I have been with instructors who still utilize this palpation and biomechanical method of examination of SI/pelvic pathology. Research pieces like the one discussed here by Adhia et al serve to muddy the water even further, as Dr. Ridgeway mentioned that this form of examination has been shown to be unreliable and mostly impractical for clinical use. I too appreciate the amount of time and effort that Adhia and colleagues put in to this study, but I think it is a shame what conclusions were developed, as well as the fact that it was published with these statements included, given other research on the topic.

    Articles, and conclusions, like these reinforce methods that should no longer have as much emphasis placed upon them. In turn, it causes further difficulty for current PT students who are just beginning to develop their own clinical reasoning and best-treatment approaches.

    We can only hope that social media outlets like ptthinktank can continue to get the word out regarding important topics in the PT scope of practice. The discussions that ensue are great!

    Good work guys.

  2. Preston,

    Your concerns are well received, and extremely well articulated. This is the problem with both current educational paradigm and clinical education, including CI’s. Students need to learn more about critical thinking, research appraisal, statistics, cognitive biases, etc. so that they can continue to integrate the current and growing science into practice. Learning skills, tools, and schools of thought is not all that helpful in my opinion. We need to be learning deep models to guide approaches, not necessarily specific techniques for certain populations.

    Thank you for joining us here!

  3. Now that I have read the full text of your letter, Kyle and Jason, I see an analogous situation to the SIJ/pain discussion in the neurodevelopmental camp – to the measurement and treatment of spasticity relative to functional movement. This point is well summarized in your last paragraph.

    I heartily agree with your comment at 7:18 above, Kyle. A key challenge for faculty is to spark critical thinking through teaching and require repeated research appraisal and give feedback. A few students will rise to critical thinking on their own but many with the capacity will move through the curriculum without the motivation to get to that level. They may become skilled clinicians with many tools and practice under the philosophical premise of their chosen mentors.

  4. Although the accuracy of the scientific approach is an appreciable fact the study does demonstrate the unreliability of its interpretation into the clinical arena. The things the study was able to invalidated are both validated clinically and demonstrated through treatment prognostically. Most such studies are too refined in their methodology to be practical or realistic for clinical application and are soley for the academic domain, limited to the strict biases that have been imposed on them. They live or die by such artificial biases. You have only got to understand the error rating in such trials to appreciate this. It does show the unfortunate dependence we now have on such validation as being the accepted true facts. What it does invalidate is the reliability of the scientific method and exposes it as a man made tool to censor certain treatment approaches. Instead of it being understood as being just one tool in the box it is taken for granted as being the only tool in the box.

  5. Hi Leith.
    I’ve read your entry a few times and I have no idea what you are trying to say.
    “The things the study was able to invalidated are both validated clinically and demonstrated through treatment prognostically.” I don’t understand this sentence at all, for example.
    Can you clarify?

  6. Hi Leith,

    You stated “What it does invalidate is the reliability of the scientific method and exposes it as a man made tool to censor certain treatment approaches. Instead of it being understood as being just one tool in the box it is taken for granted as being the only tool in the box.”

    Science is not a conspiracy laden secret society trying to censor treatment approaches. Sure, the current paradigm has it’s limits, flaws, and biases. But, science is a system of systematic thought, inquiry, and analysis that has yielded the advancements in medicine, physics, and overall understanding or our world and experiences.

    Science is currently the BEST system we have to correct for our own inherent biases and brain heuristics.

  7. Great response, Jason and Kyle. Would you send a copy of that to Scott Ward just in case some chiropractor goes on the Dr. Oz show and starts randomly manipulating audience member’s SIJs, so he can make a cogent and informed response on behalf of APTA members? Otherwise, he might go on about how PTs can restore “joint mobility” of the SI joint with manual therapy.

  8. Excellent commentary guys. I’m looking forward to some of the discussions that will certainly follow when this is published in full.

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