This is hard to differentiate as lower back and pelvis pain just feel like it hurts across the lower back and refers into the hips and bum muscles.
The lower back is felt around here, above the line of the pelvis.
The pelvis is lower, onto the bony parts, and, if painful, felt here.
The lower back or lumbar spine is typically much more locally painful in the area than the pelvis. Issues in the pelvis arise from the Sacro Iliac joint (SIJ). The SIJ gives tightness in the bum and hamstring but is not usually painful apart from when you try to run or exercise.
Lower back pain however can be very painful and can give sharp pain into the buttock, groin, thigh and lower leg as far as the foot.
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