How repeated ankle sprains damage cartilage

Yes — repeated ankle sprains can cause permanent cartilage damage, and understanding why requires looking at two mechanisms that operate simultaneously rather than in sequence.

The first is acute impact trauma. At the precise moment a sprain occurs, the talus (the bone that forms the lower part of the ankle joint) is wrenched sharply inside the joint socket, slamming against the cartilage surfaces of the tibial plafond and surrounding structures. That single collision can bruise or tear the cartilage layer there and then.

The second mechanism is slower but arguably more destructive. Once the lateral ligaments — particularly the ATFL and CFL — are stretched or partially torn, the joint no longer moves within its normal range. Every step, stair, and change of direction loads the cartilage at angles it was never designed to bear. A 2025 finite element analysis found that combined ATFL and CFL injury, the pattern seen in recurrent sprains, produced the greatest peak stress of any ligament injury combination tested, shifting that stress from the outer talar dome to the anteromedial surface — an area that tends to be affected in the osteochondral lesions clinicians find at surgery.

Think of it like repeated blows to glass that has already been weakened: the first crack may be small, but every subsequent impact finds a surface with less capacity to absorb load. Researchers describe this as an 'ankle cartilage cascade' — a progressive deterioration in which each sprain, inadequately rehabilitated, worsens the mechanical environment for whatever cartilage remains.

Why the damage doesn't heal on its own

Unlike muscle or bone, cartilage has no direct blood supply. That single fact determines everything about how ankle injuries progress. Bone heals because bleeding triggers a cascade of repair cells; muscle recovers because a rich capillary network delivers the oxygen and nutrients needed to rebuild damaged fibres. Cartilage has neither. When it is injured, no repair signal arrives, and no scaffold of new tissue forms to replace what was lost.

Even a single forceful sprain can disrupt the collagen fibre architecture within the cartilage matrix and reduce its capacity to retain the proteoglycans that keep the tissue hydrated and resilient. Those changes do not reverse with rest. When a second sprain occurs — and a third — each episode adds micro-damage to a structure that has not recovered from the last one.

It is worth being clear that this is a biological limitation of cartilage tissue, not a consequence of returning to activity too soon or resting too little. Early micro-damage is also rarely symptomatic, which means the accumulation tends to go unnoticed until it has progressed to a point where the joint begins to signal it clearly.

How common is cartilage damage after an ankle sprain

A 2025 prospective study imaging 171 acute ankle ligament injuries in athletes using 3-T MRI found cartilage or osteochondral lesions in 14% of cases — roughly one in seven. That figure applies to a single sprain event, not a history of repeated injury. Of the 33 lesions identified, 85% were classified as pure cartilage injuries with no bone involvement, which matters clinically: standard X-rays image bone and would not detect any of them. The talus was the most commonly affected surface, found in 14% of injuries; the tibial plafond was involved in 5%.

The important caveat is that this cohort was made up of athletes, where ankle loading tends to be higher and imaging protocols more rigorous than in general outpatient settings. Prevalence in recreational or less active patients is less clearly defined, and the 14% figure should not be applied directly to the broader population.

That said, a lower rate of discrete lesions does not mean the risk disappears. The instability pathway described in the previous sections can drive progressive cartilage wear even without a discrete lesion forming at the time of initial injury — the damage simply unfolds over a longer, less visible timeline.

Early warning signs that point to cartilage involvement

Distinguishing cartilage involvement from a straightforward ligament sprain is not always straightforward, particularly in the early weeks when both can produce pain and swelling. A handful of specific features, however, tend to point away from isolated ligament healing and towards the joint surface — and knowing what to look for gives patients clearer language to use when describing symptoms to a clinician.

The most telling signal is the character and location of the pain. Ligament soreness typically sits at the surface — tender to touch along the outer ankle, worst in the first days, and improving steadily with rest and physiotherapy. Cartilage pain tends to feel deeper, described by patients as an aching pressure inside the joint rather than a localised sore spot on the outside. It may be harder to pinpoint and easier to provoke with weight-bearing than with direct pressure.

A number of other features are worth noting and reporting:

• Swelling that stays — some degree of puffiness is expected after any sprain, but swelling that remains noticeably present well beyond the first few weeks — particularly if the joint still feels full during everyday activity — suggests the joint lining or cartilage surface may be involved rather than the ligament alone.
• Sounds and sensations from inside the joint — clicking, popping, or a catching feeling during movement can reflect loose or disrupted cartilage rather than soft-tissue tightness. An occasional click is common; a click that is consistently reproduced at the same point in the movement arc is more significant.
• A sense the ankle might give way — beyond the normal wobbliness of a recently sprained ankle, persistent instability during low-demand activities (walking on flat ground, descending stairs) may reflect the joint loading abnormally around damaged cartilage rather than purely weak ligaments.
• Range of motion that has plateaued — stiffness that does not continue to improve through a structured rehabilitation programme is worth raising, particularly if it is accompanied by deep aching rather than just tightness.

Research using ultrasound imaging has found measurable cartilage changes — including tissue thickening and compositional softening — in adults with a prior lateral ankle sprain history, even in younger individuals without obvious clinical symptoms. These changes correlated with lower scores on validated functional disability measures (FADI), suggesting the cartilage can be structurally altered before it becomes acutely symptomatic. This underlines why this group of features is worth flagging proactively rather than waiting for the picture to become unambiguous.

None of these features individually confirms cartilage damage, and some overlap with tendon or other ligament problems. The purpose here is not self-diagnosis but identification: if several of these experiences resonate, they are worth describing specifically and in detail at any clinical review.

What happens if cartilage damage is left untreated

The progression from cartilage damage to end-stage ankle osteoarthritis is not rapid or inevitable — but once it arrives, the treatment options narrow sharply.

According to the 2025 Kerkhoffs editorial in CARTILAGE, inadequately treated ankle cartilage injuries can advance along the cascade to end-stage osteoarthritis, at which point only two surgical routes remain: arthrodesis (joint fusion) and total ankle replacement. Neither is a straightforward solution. Ankle prostheses carry less favourable long-term outcomes than their hip or knee equivalents — longevity data are less robust and revision surgery more complex — making ankle arthroplasty a more limited proposition than patients sometimes expect.

Joint fusion eliminates pain by locking the joint permanently, but at the cost of natural ankle movement and with downstream consequences for the adjacent subtalar and midfoot joints, which absorb increased load over subsequent years.

The important counterpoint is that the cascade is interruptible. For patients who seek assessment while damage remains focal — before secondary joint-line narrowing sets in — the range of treatment options is meaningfully broader. There is no precise threshold of how many sprains or how many years marks the point of no return; the evidence does not support one. That uncertainty is itself the case for early specialist review: the window during which cartilage-preserving rather than cartilage-replacing options remain on the table does not stay open indefinitely.

When to seek specialist assessment

Three scenarios warrant a specialist referral rather than continued management through a GP or self-directed physiotherapy: pain that has not improved by six to eight weeks despite structured rehabilitation; the presence of mechanical symptoms — clicking, catching, locking, or persistent giving way — at any point; and a pattern of recurrent sprains despite completing a supervised strengthening programme.

Assessment typically combines a clinical history, functional and stability testing, and imaging. Standard X-rays are useful for ruling out bony fractures or advanced joint narrowing, but they will not show early cartilage loss. A 3-T MRI scan is the gold standard for visualising cartilage integrity, lesion size, and the extent of any subchondral bone involvement — and it is the imaging step most likely to clarify what is actually happening inside the joint.

For most patients, the pathway begins conservatively: structured physiotherapy addressing strength, proprioception, and load management remains the appropriate first stage. Where a confirmed cartilage lesion persists despite this, the range of options broadens to include regenerative treatments and, if necessary, surgical repair — the appropriate step depends on lesion size, patient activity level, and how much joint surface is involved, all of which a specialist assessment will determine.

Liquid Cartilage™ is available in the UK at the London Cartilage Clinic on Harley Street. Assessment bookings: londoncartilage.com.

1. [1] The impact of lateral ankle ligament injuries on ankle stability and talar cartilage stress: a finite element analysis. (2025). https://doi.org/10.3389/fbioe.2025.1697096 https://doi.org/10.3389/fbioe.2025.1697096
2. [2] The Prevalence, Size, and Anatomic Location of Cartilage and Osteochondral Lesions in Athletes With an Acute Ligamentous Ankle Injury. (2025). https://doi.org/10.1177/03635465251344187 https://doi.org/10.1177/03635465251344187
3. [3] Ankle cartilage health and physical activity in adults with a history of lateral ankle sprain. (2025). https://doi.org/10.1080/09593985.2025.2546083 https://doi.org/10.1080/09593985.2025.2546083
4. [4] Concomitant osteochondral lesion of the talus affects in vivo ankle kinetics in patients with chronic ankle instability. (2024). https://doi.org/10.1302/2046-3758.1312.BJR-2023-0217.R2 https://doi.org/10.1302/2046-3758.1312.BJR-2023-0217.R2