The test has been found to have a high sensitivity and specificity for a tear of the subscapularis1:
Sensitivity: 80 %
Specificity: 100 %
Another study by Márcio Schiefer addressed that lift off test has a low Sensitivity (25 %) and high Specificity(92 %)2 .
Because many patients with biceps subluxations also have partial or full-thickness tears of the subscapularis, a positive lift off test compels one to think of biceps tendon pathology as well.
With a torn subscapularis tendon, passive (and active) external rotations will be more.
Medial border winging of the scapula during the test may indicate that the rhomboids are affected
Stefko et al. 3 reported that maximum isolation of the subscapularis was achieved by placing the hand against the posteroinferior border of the scapula and then attempting the lift off. In the other positions for lift off, teres major, latissimus dorsi, posterior deltoid, or rhomboids may compensate for a weak subscapularis.
Gerber C, Krushell RJ: Isolated rupture of the tendon of the subscapularis muscle: clinical features in 16 cases. J Bone Joint Surg 73B:389–394, 1991. PMID: 1670434.
Márcio Schiefer, Yonder Archanjo Ching-San Júnior, Sérgio Maurício Silva, César Fontenelle, Marcos Genúncio Dias Carvalho, Fabio Garcia de Faria, and José Sérgio Franco: CLINICAL DIAGNOSIS OF SUBSCAPULARIS TENDON TEAR USING THE BEAR HUG SEMIOLOGICAL MANEUVER. Rev Bras Ortop. 2012 Sep-Oct; 47(5): 588–592. PMID: 27047870
Stefko JM, Jobe FW, Vanderwilde RS, Carden E, Pink M. Electromyographic and nerve block analysis of the subscapularis lift off test. J Shoulder Elb Surg. 1997;6:347–55.
Campbel’s Operative Orthopaedics 13th Book
Clinical Tests for the Musculoskeletal System, Third Edition book.
Mark Dutton, Pt . Dutton’s Orthopaedic Examination, Evaluation, And Intervention, 3rd Edition Book.