Abnormal limb bone morphology Absent ray The absence of all phalanges of a digit and the associated metacarpal /metatarsal. UMLS:C4022668 This descriptor requires, in addition to the absence of the phalanges, absence of the metacarpal or metatarsal. Compare this to Absent thumb, Absent hallux, Absent toes, and Absent fingers. In most cases, the absent metacarpal or metatarsal can be assessed by palpation, but in some cases radiographs may be useful. This definition excludes Split hand and Split foot. If a patient meets the definition of either of those terms, they should be used and Absent ray should not.