A method of treating a sacroiliac joint at a sacroiliac joint region having a sacrum, an ilium and a sacroiliac joint space therebetween, the method comprising: a) delivering a joint implant into the sacroiliac joint region, the joint implant comprising a body including a length extending between a proximal end and a distal end, an external surface extending the length, and a fixation member receiving channel extending the length and disposed in the external surface； and b) delivering a fixation member into the fixation member receiving channel thereby forming a joint implant assembly, the fixation member slidingly and matingly engaging the fixation member receiving channel in a grooved arrangement, wherein, when the fixation member is received into the fixation member receiving channel, the fixation member extends outward from the external surface of the joint implant and extends a portion of the length.
