Objectives: To examine the influence of a picture archiving and communication system (PACS) on the length of stay (LOS) for patients receiving total hip replacement (THR) or total knee replacement (TKR) procedures.

Methods: A before-and-after design was used. Data were collected on all THR and TKR procedures at Hammersmith Hospital from 1993–96. A regression approach was used to examine the influence of PACS on LOS. Factors such as patient age, sex, and physician were controlled for.

Results: Type of admission and discharge, month of procedure, complications, and number of procedures all significantly influenced LOS for patients undergoing THR. For patients receiving TKR, age, sex, admission, prosthetic complications, number of procedures, and PACS significantly influenced LOS.

Conclusions: While this study shows an apparent reduction of 25% in the average LOS for TKR patients at the time PACS was introduced, this is unlikely to be a true PACS effect and no similar reduction in LOS was shown for THR patients.