Triathlon Total Stabilizer (TS) Outcomes Study

KSS Pain score, KSS Function score, Total Combined KSS The Knee Society Clinical Rating System is comprised of two distinct sub-scores: one for pain, range of motion (ROM) and joint stability, and one for functional parameters. Sub-scores range from a potential minimum score of 0 to a maximum score of 100 points. Although the specific scores are not distinguished as excellent, good, fair, or poor, a higher value represents a better outcome. Additionally, the KSS Pain subscore and KSS Function subscore are added together to obtain a total combined score (minimum score 0, maximum score 200).

Time frame: pre-op, 2 years

Population: KSS Function Score at 2 years - One case had a calculable score for Function and not for Pain/Motion. Therefore, the case was not included in the Combined KSS Score and Participant Flow completed total of 130.

Measures the presence or absence of anterior knee pain in the groupings of the Joint Line Restoration (JLR). The 2 groups of JLR were stratified by the amount in mm that the joint line was restored to the physiological joint line postoperative. One group was those that were restored to ≤ 5 mm and the other was those that were restored to \> 5mm. Anterior knee pain is determined by clinical examination with patient and clinician whether it is present or absent.

Time frame: 2 year and 5 year postoperative

Population: Data based on knees with available radiographic and clinical data at 2 years and 5 years postoperative. There was an one more anterior knee pain evaluation as compared to knee stability and KSS Function as there was one missing value on those two evaluations.

The HSS Patella Score incorporates both subjective symptoms and objective data specific to the patellofemoral joint. It consists of one score from 0-100 with a score of 100 indicating no pain, no functional limitations, no tenderness or crepitus and normal quadriceps strength.

Time frame: pre-op, 1, 2, 5 years

Population: Participants/knees with available data. Overall number of participants and units analyzed is based upon the preoperative population.

KOOS consists of 5 subscales; Pain, other Symptoms, Function in daily living (ADL), Function in sport and recreation (Sport/Rec) and knee related Quality of life (QOL). The last week is taken into consideration when answering the questions. Standardized answer options are given (5 Likert boxes) and each question gets a score from 0 to 4. A normalized score (100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale.

Time frame: pre-op, 1, 2, 5 years

Population: Knees with available data. Overall number of participants and units analyzed is based upon the preoperative population.

The Knee Society Clinical Rating System is comprised of two distinct sub-scores: one for pain, ROM and joint stability, and one for functional parameters. Sub-scores range from a potential minimum score of 0 to a maximum score of 100 points. Although the specific scores are not distinguished as excellent, good, fair, or poor, a higher value represents a better outcome.

Time frame: pre-op, 1,2, 5 year

Population: Data based on knees with available data at 1,2 and 5 years postoperative.

This outcome measure shows the results of the KSS Functional Score for the groupings of the Joint Line Restoration (JLR). The 2 groups of JLR were stratified by the amount in mm that the joint line was restored to the physiological joint line postoperative. One group was those that were restored to ≤ 5 mm and the other was those that were restored to \> 5mm. The Functional Score of the Knee Society Clinical Rating System ranges from a potential minimum score of 0 to a maximum score of 100 points. It is based on points assigned to ability to walk, climb stairs and the use of ambulatory aids. A higher value represents a better outcome.

Time frame: 2 years, 5 years

Population: Data based on knees with available radiographic and clinical data at 2 years and 5 years postoperative.

Measures the knee stability results for the groupings of the Joint Line Restoration (JLR). The 2 groups of JLR were stratified by amount in mm that the joint line was restored to physiological joint line postoperative. One group were restored to ≤ 5 mm and the other were restored to \> 5mm. Knee stability is evaluated in the anterior-posterior (AP) and medial-lateral (ML) planes. AP drawer test determines instability in mm of the tibia. It was done in the AP plane in both JLR groupings (≤ 5mm and \> 5mm) at 2 years and 5 years. The AP measurements were sub categorized into 5mm and 5-10mm. ML is tested with a varus valgus stress test to determine any instability as measured in degrees. The ML measurements were done in both JLR groupings (≤ 5mm and \> 5mm) at 2 years and 5 years with all results in only one category of \< 5 degrees. The higher the number of degrees or mm measured the more instability in the knee.

Time frame: 2 year and 5 year postoperative

Population: Data based on knees with available radiographic and clinical data at 2 years and 5 years postoperative.

The LEAS is completed by the participant to assess activity level. Activity levels were ordered in terms of intensity from 1 to 18, with 18 indicating the highest activity level.

Time frame: pre-op, 1, 2, 5 years

Population: Participants/knees with available data. Overall number of participants and units analyzed is based upon the preoperative population.

Revision was defined as the removal of either the femoral component or the tibial baseplate component.

Time frame: 5 years

Population: Knees enrolled in the study.

The scoring system was based on the Knee Society guidelines and determined by measuring the width of the radiolucent lines for each of the zones of the implant components in millimeters. The total widths are added for each zone which produces a numerical score. Radiolucency in at least 50% of a zone and measuring at least 1 mm in width is defined as radiolucency present. Failure is defined as a score of 10 or greater, regardless of symptoms and considered as radiographic instability.

Time frame: 1, 2, 5 years

Population: Data based on knees with available data at 1, 2 and 5 years postoperative at the tibial and femoral component interface.

The SF-36 Health Survey is a 36-item patient completed questionnaire to measure general health and well-being. It includes a physical and mental status component score; each ranging from 0-100. Low values represent a poor health state and high values represent a good health state.

Time frame: pre-op, 1, 2, 5 years

Population: Participants/knees with available data. Overall number of participants and units analyzed is based upon the preoperative population.