Electronic Thesis and Dissertation Repository

Thesis Format

Integrated Article


Doctor of Philosophy


Health and Rehabilitation Sciences

Collaborative Specialization

Musculoskeletal Health Research


Bryant, Dianne M.

2nd Supervisor

Lanting, Brent A.




The overall purpose of this dissertation was to evaluate factors related to reducing length of stay after total hip and knee arthroplasty (THA and TKA).


Study 1 was a randomized controlled trial (RCT) to investigate the cost-effectiveness of outpatient THA compared to standard overnight stay. Study 2 was a prospective cohort study to assess patient- and caregiver-related factors and how they may relate to caregiver strain and level of assistance when caring for patients undergoing THA and TKA. Finally, Study 3 was a 2x2 factorial RCT to compare the trajectory of early functional recovery between the medial parapatellar and midvastus surgical approaches for TKA. The purpose of Study 3 was to determine whether the choice of surgical approach should be controlled for a future randomized trial assessing the cost-effectiveness of outpatient TKA.


For our first study, we found standard overnight stay was dominated by outpatient THA from both healthcare payer (HCP) and societal cost perspectives. Our net benefit analyses found outpatient THA to be cost-effective at all willingness-to-pay values from an HCP perspective and values of $500 or more from a societal perspective. For our second study, our model of caregiver strain found the amount of assistance provided by caregivers to be a positive predictor, and female patient sex and caregiver age to be negative predictors. Our model of caregiver assistance found length of stay to be a positive predictor and time (post- versus pre-surgery) and female patient and caregiver sex to be negative predictors. For our third study, we found the trajectory of recovery of pain within the first two weeks after surgery and stride length to have significant group by time interactions. We also found baseline outcomes to be a consistent predictor of post-surgery recovery.


Reducing the length of stay in hospital after THA and TKA procedures can be cost-effective, does not increase caregiver strain and is associated with a reduction in the amount of assistance provided by caregivers. We’ve also provided evidence for the use of either of two commonly used surgical approaches for TKA for a future randomized trial to further explore outpatient arthroplasty.

Summary for Lay Audience

Total hip and knee replacements (THR and TKR) are both very successful procedures for treating severe osteoarthritis. As need for these procedures rises each year, so does the cost to the Canadian healthcare system. Over the years, one way in which hospitals and physicians have attempted to mitigate these rising costs is by reducing the length of stay in hospital after surgery. Within the last decade, many physicians have been able to offer THR and TKR as an outpatient procedure where patients are released from hospital on the same day as their surgery. The overall aim of this dissertation was to assess factors related to reducing length of stay in hospital after THR and TKR.

Study 1 compared the cost-effectiveness of outpatient versus overnight hospital stay after THR. We found outpatient THR to be both less costly and to provide slightly greater benefit than standard overnight stay in hospital both when only looking at costs covered by the public healthcare system and when including additional patient costs (such as time off work).

Study 2 investigated which patient- and caregiver-related factors were related to caregiver strain and the amount of assistance provided by caregivers after THR and TKR. We found that when more assistance was provided, caregivers experienced more strain and that older caregivers and those caring for female patients experienced less strain. We also found that caregivers provided more assistance after surgery than before surgery and also provided more assistance the longer patients stayed in hospital. Female caregivers and those caring for female patients tended to provide less assistance than male caregivers and those caring for male patients.

Study 3 compared patient recovery early after surgery for two commonly used surgical techniques for TKR. Only the recovery of knee pain within the first two weeks after surgery and stride length were different between groups.

Included in

Orthopedics Commons