The reference is to the lungee, the type of compact turban worn in Afghanistan. The lungee is tied with relatively straight side margins, which looks like the straight margins of the pattern of alternating healing and recurring rickets
The example above isn't the best, but shows two dense bands with an intervening lucent zone.
- Biegański T, Oestreich AE, Nowak S, Rudecka M. Ebb and flow rickets in a premature infant: the Afghan turban sign. Skeletal Radiol. 1999 Nov;28(11):651-4.