Osteochondral Defect (OCD) of the Ankle

An osteochondral defect is a patch of damage to the cartilage lining the ankle joint and, often, the bone just beneath it. It most commonly affects the top of the talus (the talar dome). It usually follows an ankle sprain or twisting injury and causes deep ankle pain, swelling, stiffness or catching.

The ankle joint is formed where the shin bone (tibia) sits on the talus, a bone whose rounded upper surface is covered with smooth cartilage. An osteochondral defect (also called an osteochondral lesion) is a focal area where that surface is damaged. The damage may involve only the cartilage or extend into the bone below, and a fragment can sometimes loosen. Lesions may affect the inner (medial) or outer (lateral) side of the talus.

What are the symptoms?

• Deep, aching pain in the ankle joint
• Swelling, especially after activity
• Stiffness or reduced ankle movement
• Locking, catching or a sensation of giving way
• Pain that persists beyond normal ankle sprain recovery

Symptoms can be non-specific, and examination may show only diffuse swelling and painful movement.

What causes an osteochondral defect?

• Ankle sprains or twisting injuries
• Direct trauma or impact to the joint
• Repetitive overloading in athletes
• Osteochondritis dissecans, a spontaneous failure of the cartilage or a disruption of its blood supply

Trauma is a common cause, especially for lesions on the outer side of the talus. Medial lesions are often deeper and more likely to form cysts; lateral lesions are often shallower and more often involve a thin flake of bone.

How is it diagnosed?

Diagnosis combines clinical examination with imaging. X-rays may show bone damage or loose fragments. MRI is especially useful for assessing cartilage damage and whether the defect is stable. A CT scan may be requested for surgical planning.

More than an X-ray is often needed. A prospective study of 103 patients with chronic ankle pain (Verhagen and colleagues, Journal of Bone and Joint Surgery British) found that helical CT and MRI were significantly better than history, examination and standard radiography for detecting or ruling out an osteochondral lesion of the talus, with no statistically significant difference between CT and MRI. CT can also help judge the size, position and displacement of a lesion when planning surgery.

What are the non-surgical options?

Non-surgical treatment may be considered for small, stable lesions:

• Activity modification
• Physiotherapy
• Supportive footwear
• Anti-inflammatory medication
• Ankle bracing

Treatment is usually reserved for lesions that cause symptoms or are getting worse. The natural history of these lesions remains unclear, and the results of non-surgical care are unpredictable.

A systematic review of non-surgical treatment (Buck and colleagues, Knee Surgery, Sports Traumatology, Arthroscopy) included 30 studies and 868 patients. Pooling the 16 studies that allowed it gave a clinical success rate of 45%. On X-rays, worsening of ankle arthritis was seen in 9% of patients in the five studies that reported it. The authors described the literature as scarce and varied.

When is surgery recommended?

The surgical options depend on the size and depth of the defect:

• Arthroscopic debridement and microfracture: small holes are made in the bone to stimulate the formation of fibrocartilage, a repair tissue. This is most suitable for small, contained lesions.
• Curettage and drilling: damaged cartilage and loose fragments are removed, and the underlying bone is drilled to improve blood flow.
• Cancellous bone grafting: for larger or deeper defects, bone taken from the patient's own heel bone fills the void.
• Cartilage scaffold: a matrix is applied over the graft to support repair of the cartilage surface.

For acute injuries with a loose fragment, larger fragments may be fixed back in place and smaller or non-viable fragments removed, often through keyhole surgery. Other techniques include transfer of a plug of bone and cartilage for larger, recurrent or cystic lesions, and cell-based cartilage implantation. Smaller, contained lesions generally do better; deeper or larger lesions, cysts, a longer duration of symptoms, ankle instability and malalignment are linked to poorer results. Instability and malalignment are usually corrected before or during the procedure.

What does the research show?

A systematic review of 52 studies of primary talar osteochondral defects in adults (Dahmen and colleagues, Knee Surgery, Sports Traumatology, Arthroscopy) pooled 11 case series of bone marrow stimulation, which includes microfracture and drilling. The success rate was 82% across 317 ankles. Seven case series of plug grafting (bone with cartilage or with its lining membrane) gave a pooled success rate of 77% across 78 ankles. The review found that no treatment was superior to the others. All the pooled studies were retrospective case series.

What is recovery like?

• 0–2 weeks: non-weight-bearing; cast or boot; foot elevated
• 2 weeks: wound review; sutures removed; change to a lighter boot
• 2–6 weeks: continued non-weight-bearing while the graft site heals
• 6–12 weeks: gradual weight-bearing in the boot; physiotherapy begins
• 3–6 months: return to daily activities and low-impact exercise
• 6–12 months: return to full sport if healing is complete

How Mr Hester can help

Mr Hester is a dual fellowship-trained foot and ankle surgeon (FRCS Tr&Orth), trained at Guy's and St Thomas' and in Toronto and Calgary, and a member of BOFAS and EFAS. He sees patients privately at The London Clinic, Cromwell Hospital, King Edward VII's Hospital and HCA The Shard. His NHS practice is at King's College Hospital.

Insured patients need a GP referral and an authorisation code from their insurer. Self-pay patients are welcome. To book, call 020 7046 8004.

Frequently Asked Questions

Sources

1. Verhagen RAW, Maas M, Dijkgraaf MGW, Tol JL, Krips R, van Dijk CN. Prospective study on diagnostic strategies in osteochondral lesions of the talus. Is MRI superior to helical CT? J Bone Joint Surg Br. 2005;87(1):41–46. PMID: 15686236. https://pubmed.ncbi.nlm.nih.gov/15686236/
2. Dahmen J, Lambers KTA, Reilingh ML, van Bergen CJA, Stufkens SAS, Kerkhoffs GMMJ. No superior treatment for primary osteochondral defects of the talus. Knee Surg Sports Traumatol Arthrosc. 2018;26(7):2142–2157. PMID: 28656457. https://pubmed.ncbi.nlm.nih.gov/28656457/
3. Buck TMF, Lauf K, Dahmen J, Altink JN, Stufkens SAS, Kerkhoffs GMMJ. Non-operative management for osteochondral lesions of the talus: a systematic review of treatment modalities, clinical- and radiological outcomes. Knee Surg Sports Traumatol Arthrosc. 2023;31(8):3517–3527. PMID: 37062042. https://pubmed.ncbi.nlm.nih.gov/37062042/