The tendon sheath expand s to enco m pass
the fou r tendons as well as the peroneus tertius tendon.
The distal Iimit of the tendon sheath is near the cu neonavicular
joint. Each tendon slip extendsto its respective digit
of insertion being joined on its lateral side by atendinous
slip f rom the extensor digitoru m brevis with the exception
of the fifth digit which has no brevis insertion' The insertion
into each digit is via a complexaponeu rosis atthe metatarsophalangeal
joint level and by direct bony insertion
into the dorsu m of the m idd Ie and distal phalanges