Trevaskis (Holiness, Ethics, and Ritual in Leviticus) proposes a chiastic outline of Leviticus 21-22:
Priestly defects (Lev. 21.16-24)
A. [4 defects] blind, lame,
disfigured, an ‘overgrown limb’ (????) (v. 18)
B. [2 defects] impaired leg, impaired hand (v. 19)
C. [6
defects] hunchback, withered member, a discolouration of the eye, a ‘scab,’ ‘scurf,’damaged testicles (v. 20)
Animal defects (Lev. 22.17-25)
C.’ [6 defects] blind,
broken limb, mutilated, seeping sores, a ‘scab,’ a ‘scurf’ (v. 22)
B.’ [2 defects] an ‘overgrown limb,’ a stunted appendage (v. 23)
A.’ [4 defects] bruised, crushed,
torn, cut-off testicles (v. 24)
Among other things, the numerology is worth noting: Not only are there twelve defects listed for both groups (twelve – get it??), but they are listed in symmetrically – 4/2/6//6/2/4.