Robotic-assisted (MAKO) Versus Manual Total Knee Arthroplasty for Knee Osteoarthritis

Patient reported outcome measure, knee function questionnaire Oxford Knee Score (OKS) at 24 month. Scale from 0 (=worst) to 48 (=excellent) points Minimal clinically important difference considered as 5 points.

Patient reported outcome measure, knee function questionnaire Oxford Knee Score (OKS) at 3 and 12 months. Scale from 0 (=worst) to 48 (=excellent) points. Minimal clinically important difference considered as 5 points.

Patient reported outcome measure, knee function questionnaire KOOS points at 3, 12 and 24 months after the operation. Scale from 0 (=worst) to 100 (=excellent).

Patient reported outcome measure, knee function questionnaire WOMAC score at 3, 12 and 24 months after the operation. Scale from 0 (= excellent) to 96 (= worst) points.

Patient satisfaction question asked at 3, 12 and 24 months after the operation: If you could choose again, would you still go for the sugery? 0= no 1 = probably not 2= I don't know 4 = probably yes 5 = yes.

Length of the sick leave after the surgery, measured as days. Asked from the patient and checked from the patient files.

Asked from the patient at the 3, 12 and 24 months follow-ups visits. Has the operation changed your ability to work full-time or part-time? Options: a) yes my work changed from full-time to part-time after surgery b) no my work is as much full-time or part-time as it was before the surgey c) yes my work changed from full-time to part-time after surgery d) my work as part-time or full-time has changed from other reasons not related to the knee.

Asked from the patient at the 3, 12 and 24 months follow-ups visits. Has the physical demands of your job changed after the operation because of the knee? Options: a) yes the physical demands of my job is now lower than it was before the surgery b) no my work is as physically demanding as it was before the surgery c) yes the physical demands of my job is now higher than it was before the surgery d) the physical demands of my job has changed from other reasons not related to the knee.

Life quality questionnaire 15 dimensions at 3 follow up visits. Scale from 15 (=exellent) to 75 (=worst) points.

pain at rest and during walking on visual analoque scale (VAS) from 0 (=no pain) to 10 (=extreme pain)

Opioid usage mg/day

Blood loss evaluated by the by measuring pre- and post-operative (first day after surgery) hemoglobin g/L. Difference between the pre-operative and post-operative Hemoglobin (g/L) values.

Length of hospital stay measured in days.

Time of the operation in hours and minutes checked form patient files.

post-op CRP as a indirect soft-tissue damage measure

Knee swelling, knee diameter measured above the patella and compared to the unaffected size, the diameter difference in centimeters between the legs. Indirect soft-tissue damage measures

Range of knee motion measured with goniometry as degrees at the ward on first post-operative day and ant the 3, 12 and 24 months visits.

Knee alignment measured from post-operative weight bearing whole leg x-rays as degrees. Measured as the degrees between femoral mechanical axis line and tibial mechanical axis line.

Post-op knee x-ray taken at the first post-operative day; posterior condylar offset, measured as maximal thickness of the posterior condyle projecting posteriorly to a straight line drawn as the extension of the posterior femoral shaft cortex, measured in millimeters

Measured from post-operative knee x-rays. Insall-salvati ratio: the length of the patellar tendon in millimeters divided by the length of the patella in millimeters.

Measured from post-operative knee x-rays. Overhanging of the tibial or femoral component from medial lateral, posterior or anterior side measured as millimeters. The length between the bony edge to the edge of the component.

Measured from post-operative knee x-rays. Notching of the anterior femoral cortex. The lenght in millimeters between the anterior femoral cortex and the anterior edge femoral component in sagittal x-ray.

Revisions meaning re-operation of the knee due any reason. Checked from the patient files at 3, 12 and 24 months and five and ten years after surgery. Measured as number of revisions

Infections that recuire antibiotics or revision surgery. Checked from the patient files at 3, 12 and 24 months and five and ten years after surgery. Measured as number of infections

Need for knee manipulations under anesthesia due stiff knee. Measured as number of manipulations. Checked form the patient files at 3, 12 and 24 months and five and ten years after surgery

Unplanned post-operative re-admissions due to the knee operation. Measured as days at the ward.

Unplanned post-operative visits to the hospital emergency unit due to the knee operation, number of visits

Total cost of the treatment, measured as amount of money.