Purpose: Identify patients who likely have a full-thickness rotator cuff tear based on specific physical examination findings.
Rule:
1. Painful Arc Sign
2. Drop-arm Sign
3. Infraspinatus Manual Muscle Test
Item | 2+ variable | 3 variables |
SN | ||
SP | ||
+LR | 3.57 | 15.6 |
-LR | ||
PPV | 69% | 91% |
NPV |
SN = sensitivity – ‘SnOut’ helps rule out a disease (higher number is better – >0.9 is excellent)
SP = Specificity – ‘SpIn’ helps rule in a disease (higher number is better – greater than 0.90 is excellent))
+LR = positive likelihood ratio – ratio of positive test results in a patients with the pathology (true positives) higher number is better (> 10 is excellent)
-LR = negative likelihood ratio – ratio of negative test results in a patients with the pathology (false negatives) lower number is better (< 0.1 is excellent)
PPV = positive predictive value – percentage of patients who both test positive & have the disease (true positives)
NPV = negative predictive value – percentage of patients who both test negative & do not have disease (true negatives)
References:
1. Park HB, et al. Diagnostic accuracy of clinical tests for the different degrees of subacromial impingement syndrome. J Bone Joint Surg Am. 2005; 87(7): 1446-55.