Ankle cartilage repair: microfracture, grafts and cell-based options

When surgery is considered

For background on the condition, see osteochondral lesions of the talus. Non-surgical treatment (a boot or cast, anti-inflammatory medicine, physical therapy and bracing) is the usual first step, and surgery is considered when it fails to relieve symptoms.^[3] In a systematic review, about 45% of people treated without surgery had a good or excellent result, so many people do go on to have surgery.^[6]

Because there is no single best operation, the plan is built around the lesion (its size, depth and location, and whether it is a first-time or repeat problem) and the patient, including factors such as body weight and activity.^[2,5]

The main types of operation

Most procedures start with arthroscopy, a look inside the joint with a camera through small incisions. See ankle arthroscopy. The surgeon then removes loose fragments and unhealthy cartilage, and treats the base of the lesion in one of several ways:^[3,1]

• Bone marrow stimulation. Small holes are made in the exposed bone (microfracture or drilling), so that blood and marrow cells fill the defect and form repair tissue. It is usually done arthroscopically, and it has often been the first operation for a small, first-time lesion.^[1,7]
• Fixation. A fragment that can be saved is fixed back in place.^[1]
• Osteochondral grafting. A plug of cartilage and bone is moved from another place, usually a less important area of the knee (autograft), or a donor plug is used (allograft). Autograft plugs can cause pain at the site where they are taken.^[1]
• Cell-based and scaffold repair. Cultured cartilage cells, or a scaffold that supports the marrow-stimulation clot, are used to fill a larger defect. These are more complex and more costly.^[1,4]

What do the results show?

• Overall. An older systematic review found similar success rates for bone marrow stimulation (85%), grafting (87%) and cell-based treatment (76%), and suggested bone marrow stimulation as a first choice for first-time lesions. The authors cautioned that the studies varied too much for firm conclusions.^[1]
• Lesion size. Results after bone marrow stimulation depend on the size of the lesion. In the 14 studies that reported scores before and after surgery, average function scores improved from about 62 to 84 out of 100, and marrow stimulation may be best reserved for lesions smaller than about 107 mm² in area or about 10 mm across.^[7]
• Long-term. Ten years after arthroscopic bone marrow stimulation, 82% of procedures had not needed a revision, and the figure was unchanged at 15 years. Obesity (a body mass index of 30 or more) was linked to a higher risk of revision; lesion size was not.^[5]

Recovery

Recovery depends on the operation and the size of the lesion. A common plan is a period with the ankle protected in a boot or splint and with limited weight on the foot, so the repair tissue can settle, followed by gradual weight-bearing and physical therapy to restore motion and strength. Grafts and cell-based repairs may need longer protection than marrow stimulation. Your surgeon will give you a timetable, and a return to running or jumping sports generally takes months. See recovery after foot and ankle surgery and preparing for foot and ankle surgery.

Risks

A review of 178 studies covering 6,962 lesions found an overall complication rate of about 5%, from about 3% for marrow stimulation with a matrix to about 15% for operations using metal implants. Nerve injury was the most common complication, and no life-threatening complications were reported.^[4] Other risks include infection, stiffness, ongoing pain, a lesion that doesn’t heal or comes back, arthritis that continues to progress, and the general risks of surgery, including blood clots.

Questions to ask before deciding

• How large is the lesion, and does that change which operation you recommend?
• Is this a first-time lesion or a repeat problem?
• Do I have loose ligaments or alignment problems that should be treated at the same time?
• How long will I be on crutches or in a boot, and when can I return to sport?

When to seek care