Posterior hip instability relocation testing: a resident's case report.

BACKGROUND: Micro-instability (non-radiographic clinical instability) continues to gain recognition as a problem at the hip. Although most research has been directed to anterior hip instability, posterior hip instability (PHI) has also garnered attention. PHI is under recognized, difficult to identify, and confused with other hip pathologies such as a simple sprain or strain. A novel clinical test is introduced that may have helped identify PHI in this patient. Additionally, a conservative rehabilitation approach emphasizing stabilization exercises is described. CASE DESCRIPTION: A 29-year-old female presented with complaints of posterior lateral and anterior hip pain of 1.5 years duration. Upon initiating an aggressive stretching program, her pain worsened. Examination revealed limited and painful hip flexion, and positive anterior impingement testing for femoroacetabular impingement. Both tests were significantly less painful with more motion when retested with manual repositioning of the femoral head from posterior to anterior, referred to as posterior relocation testing. The patient was instructed to discontinue stretching. A stabilization plan was established including strengthening of the deep external rotators with trunk and lower quarter neuromuscular re-education. OUTCOME: The patient completed 12 appointments over 2.5 months. At discharge, the patient reported improvements with pain and function. The Lower Extremity Functional Scale improved from 64/80 to 77/80 and Oswestry Disability Questionnaire improved from 8 to 0%. DISCUSSION: PHI may have contributed to this patient's symptoms. The posterior relocation test may assist clinicians with identification of PHI, thus directing treatment toward stabilization and neuromuscular control rather than interventions designed to increase mobility. LEVEL OF EVIDENCE: 4.