Bone Mineral Density (BMD) in Cemented Versus Cementless Hip Resurfacing

The primary outcome is percent change in BMD (g/cm2) from baseline to the 1-year post-operative interval, as measured radiographically in zone L1. Analysis of periprosthetic BMD will be achieved using 6 zones of the femoral neck, which have been used in previous studies

Radiographs will be taken preoperatively and until 24 months post-operatively to assess for any cup loosening. Implant migration, both vertical and horizontal, will be measured on serial radiographs using the computer-assisted Ein Bild Röentgen Analyse (EBRA) software for cup migration.

The Harris Hip Score (HHS) is intended to evaluate various hip disabilities and methods of treatment. The HHS is comprised of 4 domains: pain, function, absence of deformity, and range of motion. The score has a maximum of 100 points (best possible outcome) covering pain (1 item, 0-44 points), function (7 items, 0-47 points), absence of deformity (1 item, 4 points), and range of motion (2 items, 5 points). The total score is calculated by summing the scores for the 4 domains. The higher the HHS, the less dysfunction.

The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) consists of 24 items divided into 3 subscales: Pain (5 items), stiffness (2 items), and function (17 items). This questionnaire is self-administered using the 5-point Likert-type scale (none, mild, moderate, severe, extreme). These correspond to an ordinal scale of 0-4. The scores are summed (0-100), where higher scores are indicative of worse pain, stiffness, and functional limitations.

The RAND-36 Item Health Survey assesses patient health-related quality of life and consists of 8 health concepts: physical functioning (10 items), bodily pain (2 items), role limitations due to physical health problems (4 items), role limitations due to personal or emotional problems (3 items), emotional well-being (5 items), social functioning (2 items), energy/fatigue (4 items), and general health perceptions (5 items). It also includes a single item that provides an indication of perceived change in health. Each item is scored on a 0 to 100 range, with a high score defined as a more favourable health state. Scores are averaged together to create the 8 scale scores.

The UCLA Activity Score will be used to assess the patients highest-rated activity, regardless of the frequency or intensity of participation. Patients are asked to select 1 out of 10 possible answers that best fit their current activity level (0-10). Low values are indicative of a sedentary lifestyle, while higher values are indicative of high impact activities.