This version was machine-translated from German and has not been medically reviewed. The authoritative version is the German version.
Hip ultrasound according to Graf: main group from the α angle
Assigns the α angle of the infant hip to a main group according to Graf: type I from 60°, type IIa/IIb 50–59°, below that IIc, D, III or IV – without β angle and subtypes
Calculation aid for healthcare professionals: the calculator reproduces what the sources cited assign to the inputs. Clinical assessment and every treatment decision remain with the treating physician. Inputs and results are not stored.
Frequently asked questions
Hip ultrasound according to Graf: main group from the α angle: What does this calculator compute?
Assigns a measured α angle (bony roof) of hip ultrasound according to Graf to a main group: from 60° type I (mature hip), 50 to below 60° type IIa or IIb, below 50° type IIc, D, III or IV. The calculator deliberately does not calculate the β angle and subtypes, because the type table could not be verified against a primary source. The hip type according to Graf is determined on the image; the calculator does not replace this.
Hip ultrasound according to Graf: main group from the α angle: Which sources is this calculator based on?
Graf R: Sonographie der Säuglingshüfte und therapeutische Konsequenzen. Ein Kompendium (Thieme, Stuttgart) (2010); Chang WC, Hsu KH, Lo IF, et al.: Interobserver agreement and clinical disparity between the Graf method and femoral head coverage measurement in developmental dysplasia of the hip screening (Medicine (Baltimore) 100:e26291) (2021); Lan Y, Tang L, Jin M, et al.: A stabilization device significantly improves measurement reliability and efficiency of Graf ultrasonography for developmental dysplasia of the hip (Front Pediatr 2026) (2026); Kassenärztliche Bundesvereinigung (KBV): PraxisWissen Spezial: Sonografie der Säuglingshüfte; documentation of hip ultrasound according to Graf (hip types Ia/Ib, IIa, IIc/D, IIIa, IIIb, IV) (2018)