“Gluteal Amnesia: Real, Relevant or Ridiculous?”

This week’s guest blog is from Eric Purves

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“Gluteal Amnesia”, “Sleepy Glutes”, “Lazy Butt Syndrome”

These are some common terms used to explain to clients why they are experiencing pain in their low back, sacral, hip or buttock area.  Or why they present with a perceived excessive anterior pelvic tilt, ‘tight’ hamstrings, or difficulty performing certain physical tasks.  This concept is based on the belief that the gluteal muscles not ‘working’ or ‘firing’ properly.  The rationale is that neuromuscular functionality has been forgotten from prolonged sitting, periods of inactivity, or compensation from injury.  This explanation seems simple and could be plausible if the human body worked that way.  Despite widespread acceptance by many in the rehabilitation and fitness professions, the human body is not equivalent to a mechanical device.  This reasoning is outdated and unhelpful when treating people with pain and/or treatment planning to achieve desired rehabilitation objectives.

Humans are complex biological organisms that adapt, and change based on a variety of inputs and outputs.  We are rarely symmetrical in build or movement.  Although certain body parts may be stronger or weaker than others, the human system is great at finding ways to function and move in spite of this.  The multitude of reasons why someone is in pain or suffering can seldom be reduced to a single factor like ‘lazy muscles.’

Research Informed

Often the rehabilitation and fitness world jumps onto fads that have little to no research to support them. Findings from a few research papers may be misconstrued and then wild extrapolations are made, ie Paul Hodges research on motor control and the ensuing explosion of treatments and ideas on core exercises for lumbopelvic pain.  Hint, the research for specific core exercises are no better than general exercises in long term outcomes.  Health care providers have an ethical obligation to understand and use current, relevant and quality research evidence to inform their practice decisions.  This is stated in educational and competency documents for all MSK professionals. Canadian massage therapists can check out pages 15, 17, 19 of this document.[1]

Overcomplicating the clinical encounter where the therapist assesses for faults or dysfunctions that must be fixed in order to alleviate pain and restore optimum functioning takes the healthcare provider away from what their primary objective which should be, which is to support, encourage, and help to rehabilitate to a level of function and well-being that the patient desires.  This process involves following the research evidence and incorporating our personal clinical experiences.

Here is a wonderful looking e-book with exercises and protocols for treating gluteal amnesia.  However, the premise is not backed by current research.  Most of these exercises are easy to perform and may help people with hip, buttock, or lumbosacral pain, but the narrative is at best incomplete, and at worst, it is completely incorrect.  The words and stories we tell our patients matter, a lot![2]  Therapists need to be aware the impact our explanations can have on patients[3].  Where is the evidence for these pathoanatomical tissue-based concepts?  Is this the result of some faulty research or misinterpretation of findings?

With a few decades of research to support the concept that pathoanatomical rationale is not a good indicator for pain, it is no longer acceptable to prioritize this outdated reasoning when trying to help patients suffer less and function better. The human body is not simple.  Humans are not cars or household appliances, they are complex biological organisms with unique experiences, feelings, beliefs, history and learned behaviours.  Blaming a patients’ pain experience to a biomechanical fault, tissue health or delayed muscle activation negates the complexity of pain and the human experience.  Inferring a mechanical fault or tissue-based rationale for pain and suffering can result in thoughts of being broken and fragile. This may encourage unhelpful beliefs about how the human body functions and stop people from engaging in the very activities they should be doing to move forward, movement, exercise and enjoyable activities.

The study of biomechanics, kinesiology and MSK anatomy are important to know for massage and movement-based professionals.  The importance of this knowledge and its role in pain treatment and management needs to be put into perspective.  Decades of research suggests that biomechanical and tissue-based factors may be only a portion of the patient’s pain experience and nothing needs to be fixed in the vast majority of people in order to return to a more functional life with less suffering.  Good quality chronic pain rehabilitation programs focus on function and self-management with minimal focus on pathoanatomical corrections[4].  Identifying specific dysfunction in an area and targeting treatment seems to be near impossible as subjective palpation and movement assessments are hard to replicate among therapists[5].  This is not to suggest they are useless, but not as helpful as many of us may want to believe.  Treatment strategies that focus on the entire person, rather than a specific area tend to result in better outcomes.

Assessing Gluteal Function

All this preamble matters because the assessment and treatment rationale for assessing gluteal function is based on conjecture and is absent in the research literature.  Even if gluteal amnesia was a thing it wouldn’t need to be corrected for someone to experience less pain and/or better therapeutic and functional outcomes.

A common assessment to see if the glutes are ‘firing properly’ is via prone hip extension.  The therapist is to place a hand on the upper hamstring and lower gluteal area and the other hand is placed on the upper gluteal’s and lower back.  As the patient moves their hip into hyperextension the sequence of firing was thought to be hamstrings, glutes, contralateral then ipsilateral low back muscles.  There is inconsistent agreement in the literature how these firing patterns were supposed to be measured/assessed and there seems to be some confusion regarding the clinical utility of these findings anyway.  To confound the problem even more, there is a wealth of research on the unreliability of palpation as a useful assessment tool.

During a standing postural assessment, gluteal weakness is supposed to be represented by showing an excessive anterior pelvic tilt.  What is normal and what is excessive?  The research is not consistent on this and each human is different so creating a standard to compare it with is not a good indicator.  Many people may present with a perceived excessive anterior pelvic tilt and have no pain, whereas others have the same tilt and have significant pain and suffering.  If 2 people present with similar physical findings, yet their pain experiences are vastly different, or completely absent in one, which presentation is optimal?  Which one is correct, and which one is dysfunctional?  Inferring causation based on postural or specific movement findings are problematic and does not lead to helpful clinical reasoning.  Therapists need to infer resiliency and safety and not feelings of dysfunction or being broken and damaged.

Therapists need to be willing to ask themselves questions in order to assess the validity of claims such as gluteal amnesia.  Does it sounds logical? Does the human body work that way?  What do I know about anatomy, physiology and pain mechanisms?  Do I feel confident that I know enough to assess these ideas?  If I don’t know, should I just accept this as truth, or should I seek to find some answers?  Is there research on this?  What does the research suggest?  Rather than accepting truths, we need to ask these questions and search for the answers to come up with our own informed conclusions.

 Research discussion

The authors of this website discuss some of the research on gluteal muscle activity being decreased when hip/buttock pain is experienced.  Most of these studies involved the researchers injecting a noxious stimulus into the hip/gluteal area and then taking precise measures.  Interesting for research perspectives, but not necessarily clinically relevant.  Their findings had consistency with research on other areas of the body; when someone is in pain they move and function differently.  When someone is experiencing pain in an area, they may not exhibit the same strength levels.  Is it this physical presentation of delayed muscle activation and pain induced weakness that needs addressing, or, are these findings more likely the result of the patient experiencing pain?

The research in the area of hip strength/activation is variable.  For example, alterations in hip muscle recruitment patterns, decreased strength, reduction in hip abduction force output and increased fatigue with muscle activation are all seen in people experiencing low back pain.  These findings can also be seen in asymptomatic populations.  A patient may present with gluteal weakness, imperfect gait biomechanics, perceived delay in muscle recruitment and they may have pain and/or some functional impairment, or they may not have pain?  These inconsistencies do little to support the importance of gluteal functioning for those experiencing pain.  There seems to be minimal research to support gluteal function as a specific clinical target that must be addressed to relieve pain.  Consistent with many other rehabilitation principles, patients are likely to improve doing any form of exercises or activities.  Specificity is not always necessary to achieve desired treatment outcomes.

Obviously, this article is not a systematic review and there is a wealth of research which was not considered.  Below is some interesting information from some of the literature:

This systematic review indicates that people with CLBP have gluteus maximus activity that is either delayed, has earlier onset, or has increased activation.[6]  If people with low back pain can show contradictory signs, can we infer that gluteal amnesia is causal?

This study[7] on hip abduction strength with people who have gluteal tendinopathy had the interesting finding of bilateral hip abductor weakness in those who were diagnosed with unilateral gluteal tendinopathy.  The patients had a diagnosed tendinopathy on one side, but they showed weakness on both sides!  I find this fascinating. It makes me wonder about how higher nervous system processes might be involved.  Muscle atrophy is also a common feature.  ‘It is plausible that gluteal muscle atrophy and hip abductor weakness could result from unilateral symptomatic GT as a result of disuse or inhibition of these muscles in the presence of lateral hip pain.’  The researchers do a good job here of not inferring causation.  This supports the notion that many physical findings are inconsistent and may not be related to pain or function.

This 2014 study[8] looked at the relationship between hamstring muscle length, SI dysfunction and gluteal muscle weakness.  There are some assertions in this paper that I don’t think are widely supported, although they are widely believed to be truths, ie, SI dysfunction, relationship of muscle length to pain.  The most relevant finding, patients with lumbosacral and SI pain had significantly weaker gluteal muscles.

In this 2015 study[9] the researchers injected a nerve block into the superior gluteal nerve effectively decreasing hip abduction strength by 46%. This did not alter gait biomechanical variables.  The clinical relevance was the absence of Trendelenburg’s sign even with significant reduction in hip abduction strength and no observable changes were seen during gait biomechanics.  This highlights the limited importance of the gluteal muscles in normal activities of daily living.  There were a number of limitations to this study, so the findings are not generalizable. It was a small sample size and the participants were healthy young men.

Take home points

The literature does not support gluteal amnesia as ‘a thing’ that must be treated.  Actually, according to the academic literature it doesn’t seem to exist.   Searching for good quality studies on the subject produced zero returns on both UBC’s online library and PubMed.  Google scholar wasn’t much better with only a few case studies and quotes from private fitness and rehab professions websites.  It appears that Stu McGill made mention of gluteal amnesia in a textbook from 2007, but there has been minimal mention in the literature since….?  The research I found all focused on gluteal/hip function and strength, but nothing was predictive or strongly associated with pain.

Gluteal muscle strength seems to have minor relevance to normal functioning.  When a patient presents with pain in the hip, pelvis or low back, alterations in posture, gait or strength may occur, but this is more likely due to the person being in pain, rather than causing pain.  Logically it makes sense to calm down the painful areas and have patients engage in tolerable exercises to help decrease pain and improve functioning.  However, getting overly focused on muscle recruitment patterns, hip strength, tilt and angles of the pelvis, lumbar lordosis or hamstring length will likely lead to a never-ending pain chase. Accepting that over 95% of musculoskeletal complaints resolve on their own with patient validation, education, support, and guidance for general exercise and movement principles makes our roles as therapists much easier.  Think simpler, offer a variety of treatment options that don’t just target the area of complaint and the therapist can facilitate the patient to a better long term outcome.