DO NON-STEROIDAL ANTI-INFLAMMATORY DRUGS CAUSE ENDO-PROSTHETIC LOOSENING?

Abstract

Pain relief in hip arthroplasty plays an important role in the intra/post operative stages in order to achieve an almost pain free post operative recovery period to mobilise the patient as early and safely as possible and avoid undesirable post surgical complications.

A consecutive series of 99 total hip arthroplasties in 93 patients performed by a single surgeon between December 1996 and January 2006 were assessed for signs of clinical or radiological loosening.

Intra-operative local anaesthetic mixture (Ropivacaine-Ketorolac (30mg) -Adrenaline or RKA mixture) was infiltrated into the joint capsule and surrounding tissue around the acetabular component, and into the different muscle layers in the thigh around the femoral component. A total of 150–200 mls of this mixture was injected and a further 50 mls (with 30mg ketorolac) injected through a catheter left in-situ before discharge 12 to 24 hours later. Radiographic analysis was carried out using the Hodgkinson criteria to predict acetabular component loosening and the Gruen method to determine femoral component loosening.

Of the 99 hybrid hips, 57 were right and 42 were left hip arthroplasties and 6 patients had bilateral consecutive hips done. 5 were performed for revision of fractured necks of femur in Birmingham hip resurfacings and one total hip arthroplasty revised to a hybrid and the remaining 92 were primary hybrid hip arthroplasties. The arthroplasties were performed for Osteoarthritis (89), Rheumatoid arthritis (4), and others (6). At mean follow up of 4.2 years, no aseptic loosening was noted radiologically or clinically, no components have been revised for failure or loosening and no components have dislocated.

The use of high dose local infiltration NSAIDs in the intraoperative and early post operative phase does not seem to affect prosthetic fixation at-least during short to mid term follow up of total hip joint arthroplasties.