Research Review: Gluteus Maximus Stabilization Forces at the Sacroiliac Joint
By Stefanie DiCarrado DPT, PT, NASM CPT & CES
Edited by Brent Brookbush DPT, PT, MS, PES, CES, CSCS, ACSM H/FS
Original Citation: Barker, PJ., Hapuarachchi, K.S., Ross, J.A., Sambaiew, E., Ranger, T.A., and Briggs, C.A. (2013) Anatomy and biomechanics of gluteus maximus and the thoracolumbar fascia at the sacroiliac joint. Wiley Online Library. DOI: 10.1002/ca.22233 ABSTRACT
Image courtesy of Barker, Hapuarachchi, Ross, Sambaiew, Ranger, and Briggs (2013)
Why is this relevant?: As mentioned in the article: Gluteus Maximus: Superficial & Deep Fibers , cadaver dissections have revealed deep fibers of the gluteus maximus that only invest in the sacrum and ilium (that do not cross the hip). Further, a large majority of the cross-sectional area of the gluteus maximus can be attributed to fibers that cross both the sacrum and hip, implying that the gluteus maximus may have a special role in stabilization of the sacroiliac joint (SIJ) . This study takes the next step by investigating the amount of force these fibers can generate and the resulting compressive force on the SIJ, so that we may hypothesize the contribution of the gluteus maximus to SIJ stabilization.
Study Summary
| Study Design | Descriptive |
| Level of Evidence | Level IV: Evidence from a single descriptive or qualitative study |
| Subject Demographics |
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| Outcome Measures |
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| Results |
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| Conclusions | Gluteus maximus consists of fibers with multiple origins of both muscle and bone. There were a significant number of superficial and deep fibers that cross, and therefore have an effect on, the SIJ. Fibers originating from the TLF are typically used for EMG readings and can be considered a superficial layer. Muscle activity here may not accurately reflect motor unit recruitment in the deeper fibers and lead to false impressions of gluteus maximums activity and stabilization forces. Through the TLF, the gluteus maximus can exert force up to the level of L3 and may lead to compensatory lumbar extension when hip extension is not biomechanically available. |
| Conclusions of the Researchers | Cadaver dissection and calculation of the PCSA of the gluteus maximus muscle sacral fibers provides further evidence that this muscle can contribute to SIJ stabilization. Attachments via TLF allows for transfer of forces between the trunk and the lower extremities and could produce extension in the lower lumbar region. |
Review & Commentary:
Cadaver dissection provides higher quality information about muscle fiber attachments than can be attained from current imaging technology. Further, the ability to exert a force on individual fibers, without the interference of neighboring structures, allows us to consider how those individual fibers contribute to compressive, arthrokinematic or osteokinematic motions. Using cadavers does have marked disadvantages. Typically cadaver dissection means the analysis of older and possibly atrophied muscles which may result in data that does not apply to a younger, healthy population. Additionally, posterior cadaver muscles such as the gluteus maximus may be flattened from the supine position used in cadaver preparation, making the muscle fibers appear more horizontal in some areas than they would in vivo. Although the sample size in this study (n= 11 muscles) was small, the findings did not vary significantly between the bodies, implying high reliability. The information gathered in a cadaver dissection of this nature provides further insight into the functional anatomy of the human body, moving beyond gross anatomy, and adds to the picture of human movement science we seek to complete in our search for congruence .
Why is this study important?
This study supports the findings of a previously reviewed article Gluteus Maximus: Superficial and Deep Fibers that, through cadaver dissection, documented deep fibers of the gluteus maximus exclusively crossing the SIJ and contributing to its stability. The current study investigated not only fiber bundle (fascicle) origins but their orientation, cross sectional areas and predicted force generation to further understand how the gluteus maximus can provide a stabilizing compressive force at the SIJ.
How does it affect practice?
Through its attachment to the TLF (unique to humans), the gluteus maximus is a component of the Posterior Oblique Subsystem , and as such contributes to stabilization of the kinetic chain and the transfer of forces from the lower extremities to the trunk and upper extremities. This study validates gluteus maximus activation and/or motor control training as an integral part of any exercise program to target low back pain, SIJ pain, and pelvic instability due to the combination of significant compressive force and perpendicular alignment at the SIJ. It is unclear at this time if the deeper fibers that produce a compressive force at the SIJ are activated with general gluteus maximus activation or if they will require a different exercise for motor unit recruitment.
How does it relate to Brookbush Institute Content?
The relationship between under-activity of the gluteus maximus and SIJ dysfunction is noted in the predictive model of Sacroiliac Joint Dysfunction (SIJD) , as well as Lumbo Pelvic Hip Complex Dysfunction (LPHCD). This study may be evidence of the cause of this relationship, as opposed to the simple observation and hypothesis used to construct the model. Further, this study provides evidence of the relationship between the gluteus maximus , latissiumus dorsi , thoracolumbar fascia, lumbar and sacral joints, and their importance in stability of the SIJ via the Posterior Oblique Subsystem (POS) (Brookbush Institute includes the gluteus medius in the POS). Previous evidence discussed in Gluteus Maximus: Superficial and Deep Fibers indicates the gluteus maximus may co-contract with the transverse abdominis . To that point, this study's findings suggest that TVA Activation and Gluteus Maximus Activation must be considered when addressing LPHCD & SIJD.
Transverse Abdominis (TVA) Isolated Activation
Gluteus Maximus Isolated Activation
TVA and Gluteus Maximus Activation and Progressions
Gluteus Maximus Reactive Integration
Squat to Row (Posterior Oblique Subsystem Integration)
Static Lunge to Row POS Integration Progressions
Reverse Lunge to Row Posterior Oblique Subsystem Progressions
Squat to Row Sled Pull (Power progression for Posterior Oblique Subsystem)
Review of Core Subsystems
Gluteus Maximus Snippet from Functional Anatomy Rowan U
© 2014 Brent Brookbush
Questions, comments, and criticisms are welcomed and encouraged