Contact pressure distribution of the hip joint during closed reduction of developmental dysplasia of the hip: a patient-specific finite element analysis

Table 1 The relationship of length and PCSA under different flexion angle for different muscle

Number	Muscles	Friederich PCSA (mm²)	FA 0° PCSA (mm²)	FA 0° ML (mm)	FA 45° ML (mm)	FA 65° ML (mm)	FA 80° ML (mm)
1	Pectinus	903	A1 = 903*α	31.5	49.1	55.7	59.3
2	Adductor Magnus (minimus)	2552	A2 = 2552*α	63.3	88.5	96.0	100.2
3	Adductor brevis	1152	A3 = 1152*α	72.4	97.2	104.5	108.7
4	Adductor longus	2273	A4 = 2273*α	93.5	121.5	130.8	135.4
5	Adductor Magnus (middle)	1835	A5 = 1835*α	111.3	134.9	141.6	146.1
6	Adductor Magnus (posterior)	1695	A6 = 1695*α	134.8	161.7	170.4	175.8
7	Gracilis	373	A7 = 373*α	137.4	164.0	172.9	177.9

PCSA physiologic cross sectional area [11], FA flexion angle, ML muscle length, a: a unknown coefficient, which can be used to predict the new PCSA, according to the Friederich PCSA

ISSN: 1471-2474