坠落致臀部着地的急性创伤导致尾骨的前屈,损伤骶尾部或尾骨间关节或韧带周围结构,导致过度活动或半脱位和疼痛。直接创伤可造成骶尾部或尾骨间关节的骨折。
特发性尾骨痛的病理生理机制尚不清楚。反复的尾骨后应力可能损伤韧带结构。骶尾关节的退变是尾骨痛突出的病理特征,[8]Bayne O, Bateman JE, Cameron HU. The influence of etiology on the results of coccygectomy. Clin Orthop Relat Res. 1984;190:266-272.http://www.ncbi.nlm.nih.gov/pubmed/6488643?tool=bestpractice.com此类患者可从尾骨切除术中获益。[9]Balain B, Eisenstein SM, Alo GO, et al. Coccygectomy for coccydynia: case series and review of literature. Spine. 2006;31:E414-E420.http://www.ncbi.nlm.nih.gov/pubmed/16741442?tool=bestpractice.com麻醉下激发性的间盘造影对于诊断间盘来源的尾骨痛的确诊率为70%,[10]Maigne JY, Guedj S, Straus C. Idiopathic coccygodynia. Lateral roentgenograms in the sitting position and coccygeal discography. Spine. 1994;19:930-934.http://www.ncbi.nlm.nih.gov/pubmed/8009351?tool=bestpractice.com强调骶尾关节退变在尾骨痛中的重要性。盆底肌肉痉挛(尾骨肌和肛提肌)与尾骨痛被一致认为相关联,梨状肌痉挛可伴有大腿的牵涉痛。[11]Thiele G. Coccygodynia and pain in the superior gluteal region. JAMA. 1937;109:1271-1275.[12]Thiele GH. Coccygodynia; the mechanism of its production and its relationship to anorectal disease. Am J Surg. 1950;79:110-116.http://www.ncbi.nlm.nih.gov/pubmed/15399360?tool=bestpractice.com尾骨是由骶4,骶5和尾骨神经支配的,骶神经病变可以导致牵涉痛。