Acetabular Liner Dissociation following Total Hip Arthroplasty: A Rare but Serious Complication That May Be Easily Misinterpreted in the Emergency Department

Table 1

Findings suggestive of liner dissociation in the acutely painful THA.

History	(i) Sudden onset of hip/groin pain in a previously well-functioning prosthesis; (ii) New “grinding/clicking” noise from affected hip; (iii) Difficulty fully weight bearing
Examination	(i) Audible “grinding/clicking” with passive hip movements; (ii) Lack of significant limb shortening/rotation
Investigations	AP Hip X-ray; Grossly eccentric superior migration of femoral head within acetabular shell; Lateral Hip X-ray; Medial migration of femoral head within acetabular shell. Excludes dislocation as confirms prosthetic femoral head lies within acetabular shell on a tangential view