Stages:
1) 0-3 mos. Mild pain with motion, pre-adhesive stage, gradually limited ABD, Flex, ER and IR with pain @ end range all motions
2) Freezing; 3-9 mos, more severe pain, before end-range, now chronic pain with motions, significant loss of ROM
3) Frozen; 9-15 mos. minimal pain but significant loss of motion with rigid end-feels
4) Thawing; 15-24 mos., minimal pain, gradual improvement in ROM