This 1989 paper by Insall et al. introduces the Knee Society Clinical Rating System for evaluating total knee arthroplasty outcomes. The system uses two independent scores: a knee score (pain, stability, range of motion) and a function score (walking, stair climbing). The dual structure was created specifically to prevent patient comorbidities and aging from artificially deflating knee-specific results.
10 blocks: 40 pts
Every TKA outcomes paper published after 1989 uses this score or a derivative of it. Understanding its structure is not optional for reading the literature.
When you report or interpret TKA results, keep the knee score and function score separate. A patient with severe contralateral arthritis or cardiac disease should not appear to have a worse arthroplasty outcome than a healthy patient with an identical knee.
When scoring a patient, remember the specific thresholds that matter: 125° of motion achieves maximum ROM points, normal stair climbing requires no railing use in either direction, and a walker costs 20 function points. These are the cutoffs residents need to apply when completing outcomes forms.
The system's main practical weakness (noted in subsequent validation work) is that the function score IS influenced by age, BMI, and patient category, despite the knee score not being. Know this distinction when critically appraising studies that report only function scores as a primary endpoint.
This 1989 paper by Insall et al. introduces the Knee Society Clinical Rating System for evaluating total knee arthroplasty outcomes. The system uses two independent scores: a knee score (pain, stability, range of motion) and a function score (walking, stair climbing). The dual structure was created specifically to prevent patient comorbidities and aging from artificially deflating knee-specific results.
10 blocks: 40 pts
Every TKA outcomes paper published after 1989 uses this score or a derivative of it. Understanding its structure is not optional for reading the literature.
When you report or interpret TKA results, keep the knee score and function score separate. A patient with severe contralateral arthritis or cardiac disease should not appear to have a worse arthroplasty outcome than a healthy patient with an identical knee.
When scoring a patient, remember the specific thresholds that matter: 125° of motion achieves maximum ROM points, normal stair climbing requires no railing use in either direction, and a walker costs 20 function points. These are the cutoffs residents need to apply when completing outcomes forms.
The system's main practical weakness (noted in subsequent validation work) is that the function score IS influenced by age, BMI, and patient category, despite the knee score not being. Know this distinction when critically appraising studies that report only function scores as a primary endpoint.