Weak ankles may be a result of previous ankle injuries, but in some cases, they are a congenital (at birth) condition. The ankles are sore and give way easily while standing, walking or doing other activities.
When an ankle is injured, it may take a few weeks to many months to fully heal. Often, the injured ankle remains weaker and less stable than the uninjured one. A foot and ankle surgeon can assess ankle stability and may obtain medical imaging studies to evaluate the ankle for further damage.
Treatment for weak ankles usually includes physical therapy and bracing. Surgery may be recommended depending on the degree of instability and the response to nonsurgical approaches.
See also Chronic Ankle Instability and PTTD.