Clinical Implications of the Ankle-Hip-Abductor Connection

In part 1 of this article (last issue), I reviewed a study¹ our group published last year in JMPT, showing that ankle joint complex (AJC) manipulation has a measurable proximal effect, improving gluteus medius (GMed) activation and strength in subjects with a past history of ankle sprain and unilateral hip abductor weakness. Now let's look into the study's implications to your clinical practice, including why:

• Hip abductor deficits are a frequent, yet underrecognized finding post ankle injury
• The potential consequences of hip abductor inhibition are numerous and progressive
• These deficits aren't necessarily correctable by normal means
• Providers who specialize in manipulation are in a unique position to help the situation
• While manipulation is effective, on its own it is usually not enough

Hip Abductor Weakness and Deactivation Post Ankle Injury

Hip abductor weakness² and deactivation³ are known findings post ankle injury, although to my knowledge no one has attempted to quantify their prevalence. As a rough indicator, we screened 55 subjects with a history of past inversion sprain to identify 25 who had hip abductor weakness, or 45 percent. (Most of our subjects were DPT students who, if anything, are more likely to be doing hip abductor exercises – meaning a unilateral weakness is conspicuous.)

If anywhere near 45 percent of ankle sprain sufferers go on to develop inhibition, this could amount to a fairly high occurrence, especially in the athletic population.

The Consequences

• LBP, with trigger point and palpation tenderness over the gluteals, greater trochanter and paraspinals^4-5 (empirically, I would add the QL to the list)
• Leg pain⁶
• Adduction and internal rotation in the hip joint during weight bearing while walking,⁷ which is known to increase the Q-angle, cause genu valgum and displace the patella laterally⁸ (and create patellofemoral issues)
• Iliotibial band syndrome in distance runners⁹
• Patellofemoral OA¹⁰
• Lumbar disc disease and hip OA⁶

These are the effects of weakness; if anything, inhibition only intensifies things. Many of these effects are a form of synergistic dominance: muscles adjacent to the GMed working harder in compensation. Consequently, treating these symptoms (with adjusting, dry needling, foam rolling, etc.) is often only palliative until the underlying inhibition is addressed.

Inhibited muscles don't respond to exercise fully or appropriately. This is essentially how I define muscle inhibition to patients. Inhibition decreases muscle activation, and less motor units firing means less potential for strength gains. While you will get some response from exercise, the inhibited side tends to chronically lag behind the unaffected side.

The Good News

Adjusting AJC subluxations immediately improves GMed activation. Our study demonstrated a 12.2 percent average and 9.8 percent maximum increase in GMed activation immediately following the manipulations, fully abolishing the inhibition.

Increased activation allows for muscles to function appropriately: within 48 hours, our subjects were already producing more hip abductor force (18.5 percent average and 14.2 percent maximum), up to the same level as the unaffected side. This then sets the stage for an appropriate response to rehab and treatment efforts.

I see a lot of running injuries, and as such, I've performed thousands of AJC manipulations over the years. Having said this, our study revealed an interesting finding of which I had been unaware: While only about half of the subjects required cavitation of the proximal and distal fibular joints, 100 percent required release of the talocrural and subtalar joints.

While the exact mechanisms by which GMed reactivation occurs are not fully clear, apparently these two joints play an important role and warrant close consideration (including their associated soft tissues).

Overall, one of the biggest things we learned in this process is that we accomplish more with ankle adjusting than we understood. However, once we routinely started muscle testing the hip abductors, we also realized we were neglecting more ankle subluxations (and consequent GMed inhibition) than we knew.

Ankle Mobility and Stability Deficits Must Also Be Addressed

Ankle hypomobility (not only joint, but also soft tissue) and weakness are frequently found in patients exhibiting post-ankle-injuryy GMed inhibition. In the real world, to achieve lasting resolution of the inhibition, it takes more than adjusting: these soft tissue findings must also be addressed. Otherwise, the AJC restrictions will eventually return and resume inhibiting GMed.

Clinical Tips

I find IASTM and ART an effective combination to release the associated tight, adhesed muscles and ligaments. Common locations are the fibularis brevis and tertius, and the medial and lateral ligaments.

Both the medial and lateral ligaments are frequently adhesed and benefit from IASTM. However, the lateral ligaments are often already lengthened from prior inversion sprains, while the medial ligaments are more often truly shortened, effectively holding the ankle in an inverted position. Consequently, I usually focus my lengthening efforts (ART) on the medial side.

Performing the soft-tissue work prior to AJC adjusting allows for easier and bigger cavitations.

Rehab wise, you'll want to address any ankle balance deficits and intrinsic weaknesses you find. Additionally, patients often need to "reconnect" to GMed with an isolating exercise. Of the better validated moves,¹¹ the one I've found most helpful is a banded, small-amplitude clamshell, with the addition of a thumb directly on the GMed to feel it working (what I call clamshells with intent).

Together, this mobility, stability and isolation work will allow for a full resolution of the GMed inhibition (and the effects it causes.) At this point, more functional, larger-chain hip abductor maintenance exercises such as monster walks and single-leg squats are appropriate.

Since learning about this phenomenon, I've worked with numerous patients who were stuck in a pattern of recurring low back, hip, and knee pain relating to unresolved AJC dysfunction from past injury. Many of them had worked unsuccessfully with other quality providers and been doing appropriate rehab. Often, the ankle injury was years in the past and not a current issue, and no one had thought to ask or knew to investigate it as a root cause.

On my YouTube channel, I've posted a 30-minute video: "Hip Abductor Inhibition Treatment Protocol," sharing in more detail best practices on muscle testing, ankle adjusting, soft-tissue work and rehab: everything you will need to find and successfully treat this important clinical phenomenon.

References

1. Lawrence MA, Raymond JT, Look AE, et al. Effects of tibiofibular and ankle joint manipulation on hip strength and muscle activation. J Manip Physiol Ther, 2020 Jun;43(5):406-417.
2. Friel K, McLean N, Myers C, et al. Ipsilateral hip abductor weakness after inversion ankle sprain. J Athl Train, 2006 Jan-Mar;41(1):74-8.
3. DeJong AF, Koldenhoven RM, Hart JM, et al. Gluteus medius dysfunction in females with chronic ankle instability is consistent at different walking speeds. Clin Biomech, 2020 Mar;73:140-148.
4. Cooper NA, Scavo KM, Strickland KJ, et al. Prevalence of gluteus medius weakness in people with chronic low back pain compared to healthy controls. Eur Spine J, 2016 Apr;25(4):1258-65.
5. Sadler S, Cassidy S, Peterson B, et al. Gluteus medius muscle function in people with and without low back pain: a systematic review. BMC Musculoskelet Disord, 2019;20(1):463.
6. Kameda M, Tanimae H. Effectiveness of active soft tissue release and trigger point block for the diagnosis and treatment of low back and leg pain of predominantly gluteus medius origin: a report of 115 cases. J Phys Ther Sci, 2019 Feb;31(2):141-148.
7. Kim EK. The effect of gluteus medius strengthening on the knee joint function score and pain in meniscal surgery patients. J Phys Ther Sci, 2016;28(10):2751-2753.
8. Earl JE, Schmitz RJ, Arnold BL. Activation of the VMO and VL during dynamic mini-squat exercises with and without isometric hip adduction. J Electromyogr Kinesiol, 2001 Dec;11(6):381-6.
9. Fredericson M, Cookingham CL, Chaudhari AM, et al. Hip abductor weakness in distance runners with iliotibial band syndrome. Clin J Sport Med, 2000 Jul;10(3):169-75.
10. Sritharan P, Lin YC, Richardson SE, et al. Musculoskeletal loading in the symptomatic and asymptomatic knees of middle-aged osteoarthritis patients. J Orthop Res, 2017 Feb;35(2):321-330.
11. Boren K, Conrey C, Le Coguic J, et al. Electromyographic analysis of gluteus medius and gluteus maximus during rehabilitation exercises. Int J Sports Phys Ther, 2011;6(3):206-223.