Chronic Ankle Instability

According to statistics from the Swiss Council for Accident Prevention (bfu, 2015), almost 1 in 4 sports injuries, and also nearly 1 in 6 home and leisure injuries, affect the ankle joint [4]. Injuries to the upper ankle joint are certainly among the most frequent sports injuries in sports traumatology [1–3].

In most cases, it is an inversion sprain. During this injury, your foot twists inward across three axes of motion. In medical terms, this is called plantarflexion, adduction, and inversion of the foot. Because of the intense strain placed on the outer (lateral) ligament complex of the ankle, these ligaments often get overstretched and injured. There is a risk that this acute injury can develop into chronic ankle instability over time.

You can find out more about the structure and anatomy of the ankle joint, as well as injury mechanisms, in our first blog post, "Acute Inversion Sprain, Ligament Injuries of the Foot".

The therapy as well as the symptoms can differ significantly between an acute inversion sprain and chronic ankle instability. In this article, we focus on chronic instability.

How it becomes chronic

The consequences of an acute inversion sprain often only show up over time. On one hand, the overstretched ligament structures no longer provide enough stability to your joint; on the other hand, stretch signals used as proprioceptive input to activate the muscles are no longer triggered in time. Due to muscle overload, this can lead from an acute inversion sprain to chronic ankle instability in 20–40% of cases [1,3].

Chronic ankle instability

Chronic ankle instability is characterized by recurring inversion sprains, persistent pain in the upper ankle joint, trouble during weight-bearing activities, a subjective feeling of giving way, or difficulty walking (especially on uneven ground) [1,5].

This instability can manifest mechanically and/or functionally.

Mechanical instability includes, among other things, pathological ligamentous laxity and limitations following capsuloligamentous injuries (e.g., due to scarring, poor wound healing), as well as a reduced range of motion in dorsiflexion (pulling your toes up toward you).

Functional instability presents as a muscular deficit and a subjective feeling of instability. One reason for this is a decline in proprioceptive neuromuscular potential, which leads to reduced joint control [1,6]. This was already researched in a 1965 study: it showed that frequent ligament injuries to the ankle lead to a sensory deficit that affects the surrounding muscles (reduced proprioceptive neuromuscular potential) [7].

Consequences of chronic ankle instability

In 55% of cases, chronic ankle instability is the primary cause of ligamentous posttraumatic osteoarthritis[8]. A retrospective study from 2019 shows that people with chronic ankle instability, due to repetitive inversion sprains, develop an osteochondral lesion of the talus earlier [9]. This means that the bone connecting your lower leg and foot develops premature osteoarthritis, which can show up as pain under load, swelling, and reduced range of motion in the ankle joint. To prevent these long-term issues as much as possible, proper treatment right from the acute stage is recommended. Otherwise, effective treatment of chronic ankle instability is essential.

Therapy and treatment for chronic ankle instability

Therapeutic treatment is based on both mechanical and functional aspects. That means the goal is to improve both your mobility and your motor control.

When treating mechanical instability, all joints of your foot and lower extremity are tested for mobility. Any restrictions found are then addressed through active and passive mobilization so that your correct dynamic ankle biomechanics can be restored [10].

This can be done using manual techniques in osteopathy and Physiotherapy.

Especially with chronic ankle instability, however, functional, active therapy and training should clearly be the main focus!

The goal here is for you to be able to perform all your activities with confidence again, overcome your fear of moving the wrong way, and rebuild trust in your joint. This mainly involves active exercises and training methods where you work on coordination, balance, strength, endurance, and agility. A structured, gradual progression is crucial. This means you start with simple static exercises before increasing the challenge with dynamic and more complex movements. Another important aspect is to gradually incorporate non-cyclical, sport-specific exercises to prepare your joint for real-life conditions during sports or your daily routine [11].

Conclusion

Don't underestimate injuries from an inversion sprain of the foot. Especially if you twist your ankle repeatedly, you shouldn't take it lightly! An acute inversion sprain can lead to chronic ankle instability, even if the injury seems quite harmless at first glance! Have it checked out and consider proper treatment to prevent long-term damage or ongoing pain.

Premature osteoarthritis in the ankle joint is a potential long-term consequence of an acute inversion injury or chronic ankle instability in more than half of cases.

Even if you have been twisting your ankle for years and have loose ligaments, it is not too late to support you with tailored therapy!

If you need us, we are here for you!

Your BodyLab team, your specialists for a stable ankle

Osteopathy and Physiotherapy | Rehabilitation and Training

Zurich Altstetten

Find out more on our page about Torn Ankle Ligaments.

References

1.         Chronic ankle instability in sports – a review for sports physicians.

Valderrabano V, Leumann A, Pagenstert G, Frigg A, Ebneter L, Hintermann B.

Sportverletz Sportschaden. December 28, 2006;20(04):177–83.

2.         Predicting balance improvements following STARS treatments in chronic ankle instability participants.

Wikstrom EA, McKeon PO.

Journal of science and medicine in sport. 2017;20(4):356–61.

3.         Six Sessions of Anterior-to-Posterior Ankle Joint Mobilizations Improve Patient-Reported Outcomes in Patients With Chronic Ankle Instability: A Critically Appraised Topic.

Wikstrom EA, Bagherian S, Cordero NB, Song K.

Journal of sport rehabilitation. 2018;1–4.

4.         bfu_2.265.01_status 2015 – statistics of non-occupational accidents and safety levels in Switzerland.pdf.

5.         Acute inversion sprain of the upper ankle joint – a trivial injury?

Leumann A, Tsaknis R, Wiewiorski M, Valderrabano

V. :3.

6.         Leumann A, Frigg A, Pagenstert G, Ebneter L, Hintermann B, Dick W, et al. PREVENTION. Sports Orthopaedics and Traumatology. September 2006;22(3):155–

7.         The etiology and prevention of functional instability of the foot.pdf.

8.         Ligamentous Posttraumatic Ankle Osteoarthritis.

Valderrabano V, Hintermann B, Horisberger M, Fung TS.

Am J Sports Med. April 1, 2006;34(4):612–20.

9.         Early stage and small medial osteochondral lesions of the talus in the presence of chronic lateral ankle instability: A retrospective study.

Ikoma K, Kido M, Maki M, Imai K, Hara Y, Ikeda R, et al.

Journal of Orthopaedic Science 2020 Jan;25(1):178-182. doi: 10.1016/j.jos.2019.02.003. Epub 2019 Feb 21

10.      Joint mobilization improves spatiotemporal postural control and range of motion in those with chronic ankle instability.

Hoch MC, McKeon PO.

Journal of orthopaedic research: official publication of the Orthopaedic Research Society. 2011;29(3):326–32.

11.      acute_ankle_sprain_KNGF-Guidline.pdf.