The Joint Defense Council (JDC) and the Permanent Military Commission (PMC) of the Arab League were created in 1950, with the JDC in existence until at least August 2015. Since then, both bodies seem to have been superseded by or absorbed into other organizations.
There is no mention of either organization on the current Arab League website, but both organizations are mentioned on the Arab League 24th Summit page (March 2013) as two of the four Defense and Economic Cooperation Bodies.
On the PMC,
Over the decades, it has been as effective as its parent
organization in achieving security cooperation between Arab League
member states — which is to say, not very effective. Regional events
quickly caught up with this formal attempt at security cooperation as the Egyptian monarchy fell to a military coup in 1952 and the Arab
Cold War hardened divisions between nationalist republics and
conservative monarchies. A decade on, the original signers of the
treaty could be split almost evenly between the two camps—Egypt, Iraq,
and Syria in the nationalist column, and Saudi Arabia, Jordan, and
Yemen among the leading monarchies. Lebanon was caught in the middle.
Recent references to the JDC and the PMC are scarce and reports on Arab military co-operation usually don't even mention either organization (for example, this March 2015 report on the formation of a unified military force). One of the most recent reports (August 2015, with reference to the March meeting above) on the JDC only serves to underline how little has been achieved:
The Joint Defence Council meeting scheduled for Thursday at the Arab
League headquarters in Cairo has been postponed as requested by the
The Joint Defense Council meeting was to draft a protocol for an Arab
The General Secretariat added that the meeting was postponed to
unspecified date after the secretary general consulted Egypt, the
current president of the Arab Summit.
Source: 'Arab League postpones Joint Defence Council meeting' (ahramonline)
This lack of achievement on co-operation has not just been evident in military matters but also in the area of planned economic integration, as the report Middle East Dilemma: The Politics and Economics of Arab Integration (Center for Contemporary Arab Studies, Georgetown University - pdf) makes clear.
Current attempts, encouraged by the Trump administration, at forming what is being dubbed an 'Arab NATO' or "Middle East Strategic Alliance" (MESA) do not seem to make any mention of either the JDC or the PMC.