Welcome to NeuroTalk. HBOT has been discussed may times. There is research ongoing but the past research is inconsistent. It shows improvements for some people after 60 to 80 treatments.

Your arm numbness is also symptomatic of a neck injury that is common with concussions. You may be laying in a good posture that relieves some of the neck issues during the beneficial treatments.

What symptoms are you experiencing ? You have not told us anything about your injury, diagnostics or other treatments. PCS is not a single diagnosis. It is a cluster of symptoms that are best treated individually. As a cluster, the best you can do is read the Vitamins sticky at the top since it is beneficial to any injury to the nervous system.

Keep in mind that daily behaviors can quickly undo any good a single HBOT may provide. A big part of recovery is avoiding stresses that slow recovery or even cause a relapse.

My best to you.