Inclusion Criteria:  Ability to provide informed consent. 40 patients: 20 preoperative THA, 20 postoperative THA; Sex: 20 men, 20 women; Age: 20 patients ≥ 70 years, 10 patients 50-70 years, 10 patients 18-50 years.  Exclusion Criteria:  - Patients with lumbosacral hardware, contralateral THA.