Summary THA Iliopsoas Impingement is an under recognized cause of recurrent groin pain after total hip replacement which may be caused by a malpositioned acetabular component. Diagnosis may be suspected clinically with pain with resisted seated hip flexion or straight leg raise and the presence of anterior cup overhang on CT. Diagnostic cortisone injection into iliopsoas sheath is helpful in diagnosis. Treatment is generally arthroscopic iliopsoas tenotomy in the setting of normal cup position. Revision of the acetabulum component may be indicated in cases of excessive anterior overhang. Etiology May be caused by retained cement malpositioned acetabular component limb length discrepancy excessive length of screws Anatomy Illiopsoas Presentation Symptoms groin pain average time from index procedure to symptom onset is 20 months Physical Exam findings are subtle and may include slight limp tenderness in the groin. palpable snap may be detected (rare) provocative tests pain may be reproduced or exacerbated by resisted seated hip flexion or straight leg raise Imaging Radiographs required views AP pelvis AP and lateral of hip CT scan helpful to determine postition of prosthesis and rule out other caused of symtpoms MRI usually not valuable due to artifact. Studies Diagnostic injection diagnostic cortisone injection into iliopsoas sheath is helpful in diagnosis Treatment Nonoperative observation indications rare most patients require operative intervention for complete resolution of symptoms Operative arthroscopic iliopsoas tenotomy indications in cases of normal post-op radiographs acetabular component revision indications in cases of excessive anterior cup overhang Technique