Kim Jong-un disappearance: What is tarsal tunnel syndrome?

South Korean spies believe Kim suffered from rare cause of ankle pain and has undergone surgery

Kim Jong-Un during an inspection tour of a newly-built housing complex in Pyongyang

Intelligence officers in South Korea have said they discovered the truth behind Kim Jong-un’s mysterious 40-day disappearance from the public eye.

Spies for the National Intelligence Service (NIS) said the North Korean dictator appeared to have undergone surgery on his right ankle after he was diagnosed with tarsal tunnel syndrome.

The affliction is defined as one of the less common causes of heel pain by the NHS.

It involves the compression of the nerves that run along the sole of the foot and into a small tunnel on the inside of the ankle joint – the tarsal tunnel.

This usually occurs when a cyst forms or if the tunnel is damaged, for example by an irregular arch in the ankle. People with severely flat feet are believed to be at particular risk.

The syndrome can cause pain anywhere along the nerve, including beneath the heel, and may be aggravated by long periods walking or standing. Kim was observed limping while making public visits in the days before he disappeared.

Corrective surgery is only reserved for the most severe of cases, after more conservative treatments involving arch supports and anti-inflammatory drugs have failed.

It is a highly effective treatment, however, proving successful at relieving symptoms in around 90 per cent of cases.

After he was last shown in state media outlets on 3 September Kim re-emerged on 14 October walking with a cane. If the South Korean spies are right about the dictator’s diagnosis and treatment, he should be back to his old self in no time.