Effect of dry needling on lumbar muscle stiffness in patients with low back pain: A double blind, randomized controlled trial using shear wave elastography

Reviewed by Jerome Thomas, SPT, Tyler Tice, PT, DPT, OCS, ATC

Dry needling is an innovative treatment technique utilized by various healthcare practitioners such as physical therapists, physicians, and chiropractors. Dry needling is implemented by inserting needles into painful areas of muscle perceived to have motor abnormalities in an attempt to restore normal muscle function and alleviate higher levels of pain. These painful areas of muscle are more commonly referred to as myofascial trigger points by clinicians.

There is a growing body of new evidence and research that reinforces the clinical effectiveness of dry needling for various musculoskeletal conditions such as low back pain. However, there have been limited studies that evaluate the effect of dry needling on soft tissue stiffness after its application. This randomized controlled trial utilized ultrasound shear-wave elastography (SWE), technology that quantifies soft tissue elasticity by sending sound waves into the desired soft tissue area. Vibrations move faster through the areas of soft tissue that are more stiff and less elastic. The primary aim of this study is to compare the effects of dry needling and sham dry needling (control group), on lumbar muscle stiffness in individuals with low back pain.

There were several outcomes assessed at the end of this randomized controlled trial: self-reported pain using the numerical pain rating scale (NPRS), LBP-related disability using the Oswestry Disability Index (ODI), self-reported changes using the Global Rating of Change, as well as lumbopelvic active range of motion. The participants in this study were currently experiencing low back pain between the ages of 18 and 65. Current low back pain for the participants was defined as pain between the 12th rib and the buttocks region as well as an ODI score of at least 10%.

Following the baseline evaluation and outcome assessment, 60 participants were randomized to either receive dry needling or sham dry needling. Therefore, there were 30 participants in the dry needling group and 30 participants in the sham treatment group. Treatment was performed by an experienced physical therapist trained in dry needling and blinded to all outcomes. Treatment was applied to a total of four sites on both the lumbar multifidi and erector spinae, muscles of the low back region. During each insertion of the needle, a ‘pistoning’ (in and out motion) technique was used in an attempt to elicit a local twitch response. Each participant was instructed to perform a double knee-to-chest maneuver 6 times for 5–10 seconds to alleviate residual soreness.

The results of the study showed that the resting erector spinae muscle stiffness was lower in individuals that received dry needling than in those that received sham dry needling 1 week after treatment. Additionally, individuals that received dry needling reported statistically larger overall improvements using the Global Rating of Change scale, as well as statistically significant improvements in pain levels utilizing the numerical pain rating scale (NPRS). No serious adverse events were reported throughout the course of this randomized controlled trial.

 Clinical Application:

Dry needling can be utilized as an effective intervention for individuals with low back pain to attenuate muscular stiffness in the low back region, as well as provide improvements in pain levels. Dry needling can be a useful intervention to help reduce the activity of myofascial trigger points, decrease hypersensitivity of taut bands in skeletal muscle, as well as restore normal muscle function during routine functional activities.


Koppenhaver SL, Weaver AM, Randall TL, et al. Effect of dry needling on lumbar muscle stiffness in patients with low back pain: A double blind, randomized controlled trial using shear wave elastography. J Man Manip Ther. 2022;30(3):154-164.

The foot core system: a new paradigm for understanding intrinsic foot muscle function

Article Review by Evan Peterson PT, DPT

Over the years, there has been much discussion regarding building “core” muscle and stability. When the term “core” is used, generally the public immediately is drawn to the abdominal and trunk musculature. In this article by McKeon et al (2014), the writers discuss the importance of a different core system. They address the need for further attention to the intrinsic portion of the foot alongside the extrinsic muscle system for improved mechanics and function.

Throughout our normal gait pattern, the human foot has to go through many adjustments and adaptations to allow for the most efficient gait possible. Each phase of the gait cycle requires the different structures to stiffen or become mobile for proper energy storage and release.  If the 4 intrinsic layers of the foot do not operate appropriately it may lead to unwanted deformation of the arch, which in turn, leads to a variety of problems such as plantar fasciitis, posterior tibial tendon dysfunction, medial tibial stress syndrome, and chronic lower leg pain.

The authors discuss the origin of the human foot and its development of arches defined by long and strong ligaments, an adducted great toe, shortened lateral toes, and compaction of the mid tarsal region to help prevent collapse. Apes unlike humans also lack the pronounced Achilles tendon and plantar aponeurosis designed for storing and releasing energy required for running. Humans, unlike quadruped runners, also have the additional intrinsic foot muscle system. Quadruped runners rely almost solely on passive stability from ligaments.

Due to the above-mentioned facts, McKeon et al, suggest the idea of the “foot core system” which working together provides stability and flexibility to accommodate varying surfaces and loads. The system consists of 3 different subsystems: Passive, Active, and Neural. The passive system consists of the bones of the foot which create a half dome, the plantar fascia, and ligaments of the foot. The active subsystem of the foot consists of both intrinsic and extrinsic foot musculature. The extrinsic muscles start in the lower leg and cross the ankle joint; whereas, the intrinsic are all located below the ankle joint. The intrinsics and extrinsics along with the passive system work synergistically to allow for proper foot function. The neural system accounts for the proprioceptive aspects of the plantar fascia, ligaments, joint capsules, muscles and tendons. It is proposed that the foot intrinsics play a key role in detecting quick stretches allowing for correction in foot dome posture.

Despite the evident importance of the core muscle system, currently there is no gold standard for measurement of the foot intrinsics. Most testing looks at flexion strength which does not completely isolate the intrinsic system and also does not test the person’s ability to maintain an arch. The authors suggest an intrinsic foot muscle test, which looks at the ability to maintain and the medial longitudinal arch while in single limb stance after the therapist sets the foot in subtalar neutral. The goal is to maintain the arch without excessive global muscle involvement.

To address any deficits found, it is suggested to utilize the “short foot” exercise as opposed to toe flexion exercises like the towel crunch in order to eliminate flexor hallicus longus and digitorum longus involvement. McKeon et al relate this to the idea of the abdominal draw in maneuver used for lumbopelvic core stability. It is necessary to build a strong base to allow for the other moving parts to perform correctly. Several studies, as mentioned in this article, have shown the short foot exercise to improve balance and self-reported function in those with chronic ankle instability.

Due to the importance of our foot’s core, the authors believe barefoot/minimal footwear is ideal for training the intrinsic foot musculature. Studies have shown increase in foot core muscle size while wearing barefoot shoes as well as have demonstrated improvements in balance and postural stability. The authors do not suggest this method for those with altered sensation in their feet.

The authors believe, at first adding external support to the foot in an acute injury is acceptable; however, the support should be removed as soon as possible to allow for strengthening of the foot core.

Here at Physical Therapy First, you can work with a physical therapist 1 on 1 for an examination and be instructed in the proper way to address your foot’s core.


McKeon, P. O., Hertel, J., Bramble, D., & Davis, I. (2014). The foot core system: A new paradigm for understanding intrinsic foot muscle function. British Journal of Sports Medicine, 49(5), 290–290. https://doi.org/10.1136/bjsports-2013-092690

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