ORIGIN® vs. VANGUARD® PS Observational Study

Forgotten Joint Score

12 questions and measure the ability of the patient to forget their operated knee after the surgery.

The Self-Administered Patient Satisfaction Scale

Patients' overall satisfaction with surgery, the extent of pain relief, the ability to perform home or yard work, and the ability to perform recreational activities.

Oxford Knee Score (OKS)

Patient reported scores This Quality of Life score was developed in 1998 and validated to measure pain and function after total knee replacement. It consists of 12 questions about pain, function and mobility of the knee joint. Each question scores from 1 to 5 (1 the best and 5 the worst) and the sum of all the scores is deducted from 60 points. The best total is 48 points and the worst is 0.

EQ-5D-5L

Patient reported scores. The descriptive system comprises five dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each dimension has 5 levels: no problems, slight problems, moderate problems, severe problems and extreme problems. The patient is asked to indicate his/her health state by ticking the box next to the most appropriate statement in each of the five dimensions. This decision results in a 1-digit number that expresses the level selected for that dimension. The digits for the five dimensions can be combined into a 5-digit number that describes the patient's health state. The EQ VAS records the patient's self-rated health on a vertical visual analogue scale where the endpoints are labelled 'The best health you can image' and 'The worst health you can image'. The VAS can be used as a quantitative measure of health outcome that reflects the patient's own judgement.

Knee Society clinical rating system (KSS) Objective Knee Indicators

Surgeon reported score. It consists of 4 questions regarding the alignment and mobility of the knee joint: "Alignment" has a maximum of 25 points and is determined on a weight-bearing AP radiograph measuring the femoral-tibial (Anatomic) axis. "Instability" allows a maximum of 25 points for a knee that is stable in the coronal and saggital axis. "Joint Motion" allows one point for each 5° of joint motion. Unlike the old scoring system that allowed a maximum of 25 points the new system allows greater than 25 points for patients with greater than 125° of motion. There are deductions for flexion contracture and extension lag. The presence of recurvatum is not specifically addressed however patients with recurvatum will have significant ligament laxity in other planes that is captured in the "Instability" category of the objective score. Maximum allowable points 25+

Single Leg Stance test

Surgeon reported score. It is used to assess static postural and balance control. It is a balance assessement that is widely used in clinical settings to monitor neurological and musculoskeletal conditions. It measures the duration of exercices with eyes opened and closed in seconds.