If your ankle keeps “giving way” on uneven ground, rolls during a pickup basketball game, or simply feels wobbly walking down stairs months after your last sprain, you may be dealing with more than bad luck. Repeated ankle sprains often point to a specific, well-studied condition, and people searching for how to fix chronic ankle instability are usually looking for options beyond another round of rest and ice. The lateral ligaments on the outside of the ankle – primarily the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) – can lose some of their structural integrity after an initial sprain, and the surrounding nerves and muscles can lose some of their ability to sense joint position, setting up a cycle of repeat injury.
This article walks through what chronic ankle instability actually is, the conventional treatment ladder most clinicians recommend first, and where mesenchymal stem cell (MSC) therapy and platelet-rich plasma (PRP) fit into the conversation as complementary, still-emerging options. The goal is not to suggest a shortcut around bracing, rehab, or surgery when it is indicated, but to give a clear, evidence-based picture of how regenerative approaches are being studied for ligament healing so you can have an informed conversation with your provider.
What Is Chronic Ankle Instability?
So what is chronic ankle instability, exactly? Clinically, it is a lasting sense of ankle “giving way” or repeated sprains that persists for at least a year after an initial injury, along with self-reported instability on daily or athletic activity (Gribble et al., Journal of Athletic Training, 2014). Researchers generally separate it into two overlapping categories.
Mechanical instability refers to actual laxity in the ATFL and/or CFL – the ligaments have stretched, partially torn, or healed with excess laxity, allowing the ankle joint to move beyond its normal range. Functional instability refers to the neuromuscular side of the picture: impaired proprioception (the ankle’s sense of its own position), delayed peroneal muscle reaction time, and diminished postural control, even when ligament laxity on imaging looks relatively mild (Gribble et al., Journal of Athletic Training, 2014).
In practice, most people with chronic ankle instability have some combination of both. Common symptoms include recurrent sprains from relatively minor missteps, a persistent feeling of looseness or unpredictability, swelling that lingers after activity, and difficulty with quick direction changes or uneven terrain. Roughly 20% of acute ankle sprains are thought to progress to this chronic pattern, which is why early, adequate rehabilitation after a first sprain matters as much as treatment later on.
Conventional Approaches to Fixing Chronic Ankle Instability
Before considering any regenerative option, most orthopedic and sports medicine providers start with a structured, conservative approach – and many patients improve significantly without ever needing surgery.
Bracing and taping provide external mechanical support, limiting excessive inversion (the motion that causes most lateral ankle sprains) while the ligament and surrounding tissue continue to adapt. This is typically a first-line, low-risk step, especially during return to sport.
Balance and proprioceptive rehabilitation is considered a cornerstone of conservative management because functional instability often responds well to targeted neuromuscular retraining. Structured programs emphasizing single-leg balance, wobble-board work, and reactive strength training aim to restore the joint-position sense and peroneal reaction time that repeated sprains can erode.
Physical therapy more broadly addresses strength deficits in the peroneal and lower-leg musculature, gait mechanics, and sport-specific movement patterns, and is generally recommended for a meaningful trial period before other interventions are considered.
Surgical ligament reconstruction, most commonly the modified Broström (or Broström-Gould) procedure, directly repairs or tightens the ATFL and CFL and is generally reserved for patients whose instability persists despite an adequate course of bracing and rehabilitation. It remains one of the most established and successful surgical options for refractory cases.
How Stem Cell Therapy May Support Chronic Ankle Instability
For patients who have tried conservative care and are weighing next steps, some clinicians and researchers are exploring mesenchymal stem cell (MSC) therapy and PRP as complementary options aimed at supporting the underlying ligament tissue rather than replacing rehab or surgery outright.
MSCs are of particular interest here because researchers have successfully isolated and characterized synovial mesenchymal stem cells directly from the ankle joint tissue of patients with chronic lateral ankle instability, including from the synovium surrounding the ATFL itself, suggesting a locally available cell source relevant to this specific joint (Nakashima et al., Orthopaedic Journal of Sports Medicine, 2022).
The proposed mechanism is largely paracrine rather than a matter of stem cells physically rebuilding ligament tissue cell-by-cell. MSCs and their secreted factors – sometimes studied as “conditioned medium” or extracellular vesicles – appear to shift the local immune environment toward an anti-inflammatory state and have been associated with increased expression of type I collagen and other tendon/ligament-related markers in laboratory studies, which researchers believe may support the structural rebuilding process that damaged ligament fibers rely on (Rhatomy et al., Stem Cells Translational Medicine, 2020).
PRP, which concentrates a patient’s own platelets and growth factors, is often discussed alongside MSC therapy as a related but distinct regenerative option, and it has been studied more extensively in ankle ligament injuries to date. It is important to be direct about the current evidence: neither MSC therapy nor PRP is positioned by researchers as a substitute for structured rehabilitation or for surgical reconstruction when structural instability is significant. They are best understood as adjunctive, evolving options that may complement – not replace – the conventional treatment ladder.
The Evidence: What Research Shows
Research specifically on regenerative injections for chronic ankle instability is still limited compared with larger joints like the knee, but a growing body of work offers some useful signals.
A retrospective case series of 47 patients with chronic lateral ankle instability who received a series of three weekly PRP injections found substantial improvement in patient-reported outcomes: Cumberland Ankle Instability Tool scores rose from an average of 10.26 to 27.74, and Karlsson scores improved from 42.26 to 96.45 at three-month follow-up, with the majority of patients reporting high satisfaction and no significant adverse effects beyond transient post-injection soreness (Medina-Porqueres et al., Biomedicines, 2024). As a case series without a control group, these results are promising but not definitive.
A more rigorous randomized, single-blinded controlled trial evaluated PRP injected around the ATFL and CFL sutures immediately following modified Broström-Gould surgery, comparing it with standard postoperative management alone. In this surgical-adjunct context, the addition of PRP did not produce a statistically significant improvement in clinical or functional outcomes over standard care (Sabaghzadeh et al., Foot & Ankle Orthopaedics, 2023). Together, these two studies illustrate a pattern seen elsewhere in regenerative orthopedics: PRP and related biologic therapies may show encouraging results in observational or early-stage studies, but higher-quality, controlled research does not always confirm an added benefit, particularly when layered on top of an already-effective surgical repair.
Direct clinical trials of MSC injections specifically for chronic ankle instability remain sparse; most current MSC evidence in this joint comes from laboratory characterization of ankle-derived stem cells and from broader tendon/ligament healing research rather than large controlled ankle-instability trials. This means MSC therapy for CAI should currently be viewed as an evolving, evidence-informed option rather than an established, guideline-backed treatment.
Safety Considerations and Realistic Expectations
Before considering any regenerative approach, an accurate diagnosis matters. Clinicians typically confirm chronic ankle instability through a physical exam that includes manual stress testing (such as the anterior drawer and talar tilt tests) alongside patient-reported history, and MRI or stress imaging may be used to characterize the degree of ligament laxity or any associated cartilage involvement.
It is essential to understand that stem cell therapy and PRP for ligament conditions, including chronic ankle instability, are not FDA-approved treatments for this indication. Autologous PRP and MSC-based injections used for orthopedic applications are generally offered as part of physician-directed care rather than as an FDA-cleared therapy for ligament repair, and patients should treat marketing claims of guaranteed results with appropriate skepticism. As the research above shows, outcomes vary between study designs, and rigorous controlled data specific to the ankle remain limited.
Anyone exploring these options should seek out a qualified orthopedic or regenerative medicine provider who can review imaging, discuss the strength of current evidence honestly, and help place stem cell therapy or PRP appropriately alongside – not instead of – proven conservative and surgical care.
Frequently Asked Questions
What is chronic ankle instability?
Chronic ankle instability (CAI) is a persistent feeling of the ankle giving way or repeated sprains lasting a year or more after an initial injury, caused by a combination of lateral ligament laxity and impaired proprioception or neuromuscular control (Gribble et al., Journal of Athletic Training, 2014).
How to fix chronic ankle instability without surgery?
Most people start with bracing, proprioceptive and balance training, and structured physical therapy targeting peroneal strength and joint-position sense. Many patients see meaningful improvement with a consistent rehab program, and surgery is generally reserved for cases that do not respond adequately to conservative care.
Can stem cell therapy fix chronic ankle instability?
Stem cell therapy is not positioned as a cure or a guaranteed fix. Early research suggests MSC-derived factors may support ligament tissue repair through anti-inflammatory and regenerative signaling, but controlled clinical trials specific to chronic ankle instability are still limited, so it is best considered a complementary, evolving option.
Is PRP effective for chronic ankle instability?
Evidence is mixed. A case series reported meaningful improvement in stability scores after PRP injections, while a randomized controlled trial found no added benefit when PRP was combined with ligament reconstruction surgery, so results likely depend on the clinical context and injury severity.
Is stem cell therapy for ankle ligaments FDA-approved?
No. Stem cell and PRP injections for ligament conditions, including chronic ankle instability, are not FDA-approved treatments for this use. They are typically offered as physician-directed care, and patients should discuss the evidence and risks with a qualified provider.
When is surgery needed for chronic ankle instability?
Surgical ligament reconstruction, such as the modified Broström procedure, is typically considered when structured bracing and rehabilitation fail to resolve symptoms after an adequate trial, generally several months, and imaging or exam findings confirm significant mechanical laxity.
How is chronic ankle instability diagnosed?
Diagnosis usually combines a detailed injury history, manual stress tests like the anterior drawer and talar tilt, and sometimes MRI or stress imaging to assess the extent of ligament laxity and rule out other structural damage.
Can chronic ankle instability get better on its own?
It’s uncommon for the underlying mechanical or neuromuscular deficits to fully resolve without intervention. Most improvement comes from active rehabilitation and, when appropriate, bracing or surgery, rather than from time alone.
Key Takeaways
- Chronic ankle instability involves a combination of lateral ligament laxity (mechanical instability) and impaired balance or muscle reaction time (functional instability).
- Roughly 1 in 5 ankle sprains may progress to a chronic instability pattern, making early, thorough rehab after the first sprain important.
- Learning how to fix chronic ankle instability typically starts with bracing, proprioceptive training, and physical therapy before any other intervention is considered.
- Surgical reconstruction, such as the modified Broström procedure, is generally reserved for cases that don’t respond to an adequate trial of conservative care.
- Mesenchymal stem cells have been successfully isolated from ankle joint tissue in patients with this condition, supporting interest in regenerative research.
- MSC and PRP therapies appear to work primarily through paracrine, anti-inflammatory, and collagen-supporting signaling rather than direct tissue replacement.
- Clinical evidence on regenerative injections for chronic ankle instability is mixed and still developing, with promising case series but less clear benefit in controlled surgical-adjunct trials.
- Stem cell therapy and PRP are not FDA-approved for ligament repair and should be discussed with a qualified provider as complementary, not standalone, options.
Curious whether stem cell therapy could complement your ankle recovery plan alongside proven rehab and surgical care? Schedule a consultation with the Ways2Well team to discuss a personalized, evidence-informed approach.
For related reading, see our articles on stem cell therapy for ankle injuries and regenerative medicine for ankle pain and repair.
References
- Gribble PA, Delahunt E, Bleakley CM, Caulfield B, Docherty CL, Fourchet F, Fong DT, Hertel J, Hiller CE, Kaminski TW, McKeon PO, Refshauge KM, van der Wees P, Vicenzino B, Wikstrom EA. “Selection Criteria for Patients With Chronic Ankle Instability in Controlled Research: A Position Statement of the International Ankle Consortium.” Journal of Athletic Training, 2014;49(1):121-127. DOI: https://doi.org/10.4085/1062-6050-49.1.14
- Nakashima H, Uchida S, Hatakeyama A, Murata Y, Yamanaka Y, Tsukamoto M, Sekiya I, Sakai A. “Isolation and Characterization of Synovial Mesenchymal Stem Cells Derived From Patients With Chronic Lateral Ankle Instability: A Comparative Analysis of Synovial Fluid, Adipose Synovium, and Fibrous Synovium of the Ankle Joint.” Orthopaedic Journal of Sports Medicine, 2022;10(5):23259671221094615. DOI: https://doi.org/10.1177/23259671221094615
- Medina-Porqueres I, Martin-Garcia P, Sanz-De-Diego S, Reyes-Eldblom M, Moya-Torrecilla F, Mondragon-Cortes R, Rosado-Velazquez D, Gomez-Caceres A. “Platelet-Rich Plasma Injections in Chronic Lateral Ankle Instability: A Case Series.” Biomedicines, 2024;12(5):963. DOI: https://doi.org/10.3390/biomedicines12050963
- Sabaghzadeh A, Zarei Kurdkandi H, Ebrahimpour A, Biglari F, Jafari Kafiabadi M. “Efficacy of Platelet-Rich Plasma for Chronic Lateral Ankle Instability After Modified Broström-Gould Surgery: A Randomized, Single-Blinded, Prospective Controlled Trial.” Foot & Ankle Orthopaedics, 2023;8(2):24730114231168633. DOI: https://doi.org/10.1177/24730114231168633
- Rhatomy S, Prasetyo TE, Setyawan R, Soekarno NR, Romaniyanto, Sedjati AP, Sumarwoto T, Utomo DN, Suroto H, Mahyudin F, Prakoeswa CRS. “Prospect of Stem Cells Conditioned Medium (Secretome) in Ligament and Tendon Healing: A Systematic Review.” Stem Cells Translational Medicine, 2020;9(8):895-902. DOI: https://doi.org/10.1002/sctm.19-0388
Author: Ways2Well Editorial Team
Reviewed by: Scientific Advisory Board member