Special Test

Crank Test | Shoulder SLAP Lesions

Last updated on: February 20, 2024

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Crank Test is used to test for Labral Injuries and SLAP lesions (Superior Labrum from Anterior to Posterior tears) of the shoulder. It was first described by Liu et al. in 1996.

How do you do the Crank Test?

This test can be performed with the patient either standing or supine. The humerus is maximally elevated with the elbow in approximately 20° of flexion. The examiner uses one hand to hold the subject’s wrist while the other hand is used to apply an axial force through the humerus towards the glenoid. The humerus is then rotated internally and externally against the glenoid, producing mechanical shear across the labrum.

What does a positive Crank Test mean?

Crank Test is Positive when there is clicking or pain in the glenohumeral joint during the maneuver.

See Also: SLAP lesions

Sensitivity & Specificity

A prospective evaluation study ¹ found that Crank Test was found to have a high sensitivity and specificity for diagnosing labral tears in a series of 62 patients who presented with shoulder pain that was refractory to 3 months of conservative management:

Sensitivity: 91 %
Specificity: 93 %

A study was done by S H Liu, to compare between magnetic resonance imaging and clinical examinations for diagnosis of glenoid labral tears.

The crank test has been found to have a higher sensitivity (90%) than MRI (59%) and equal specificity (85%) to MRI based on a study to compare between magnetic resonance imaging and clinical examinations for diagnosis of glenoid labral tears.²

Test and Study Quality	Description and Positive Findings	Population	Interexaminer Reliability
Crank test	Patient is supine with shoulder in 160 degrees of abduction and elbow in 90 degrees of flexion. The examiner applies a compressive force to the humerus while repeatedly rotating it into internal and external rotation. Positive if click is produced during the test	40 subjects with shoulder pain	κ = .36 (-.07, .59)
Crank test	As above	55 patients with shoulder pain scheduled for arthroscopic surgery	κ = .20 (-.05, .46)

Population	Reference Standard	Sens	Spec	+LR	-LR
Pooled estimates from four studies (n = 282)	Labral tear diagnosed by arthroscopy	.34 (.19, .53)	.75 (.65, .83)	1.4 (.84, 2.2)	.88 (.69, 1.1)
847 patients who underwent diagnostic arthroscopy of the shoulder	Partial biceps tendon tear visualized during arthroscopy	.34	.77	1.5	.86
62 patients scheduled to undergo arthroscopic shoulder surgery	Glenoid labral tear observed during arthroscopy	.91	.93	13.0	.10

What is SLAP Lesion?

SLAP lesions are described as superior labral lesions that are both anterior and posterior.
There are several injury mechanisms that are speculated to be responsible for creating SLAP lesions ranging from single traumatic events to repetitive microtraumatic injuries.
During a dislocation, tears to the glenoid labrum occur in isolation or in combination. The superior aspect of the labrum is more mobile and prone to injury due to its close attachment to the LHB tendon.
The lesion typically results from a FOOSH injury, sudden deceleration or traction forces such as catching a falling heavy object, or chronic anterior and posterior instability.

Snyder and colleagues classified SLAP lesions into four main types by signs and symptoms:

Type I: This type involves a fraying and degeneration of the edge of the superior labrum. The patient loses the ability to horizontally abduct or externally rotate with the forearm pronated without pain.
Type II: This type involves a pathologic detachment of the labrum and biceps tendon anchor, resulting in a loss of the stabilizing effect of the labrum and the biceps.
Type III: This type involves a vertical tear of the labrum, similar to the bucket-handle tear of the knee meniscus,
although the remaining portions of the labrum and biceps are intact.
Type IV: This type involves an extension of the bucket handle tear into the biceps tendon, with portions of the labral flap and biceps tendon displaceable into the G-H joint.

Several special tests can be used to help identify the presence of a SLAP lesion including:

Snyder and colleagues classification for SLAP lesion — SLAP Tear

Reference

S H Liu, M H Henry, S L Nuccion. A prospective evaluation of a new physical examination in predicting glenoid labral tears. Am J Sports Med. Nov-Dec 1996;24(6):721-5. doi: 10.1177/036354659602400604. PMID: 8947391.
Liu SH, Henry MH, Nuccion S, Shapiro MS, Dorey F. Diagnosis of glenoid labral tears. A comparison between magnetic resonance imaging and clinical examinations. Am J Sports Med. 1996 Mar-Apr;24(2):149-54. doi: 10.1177/036354659602400205. PMID: 8775111.
Magnus Arnander and Duncan Tennent. Clinical assessment of the glenoid labrum. Shoulder Elbow. 2014 Oct; 6(4): 291–299. PMID: 27582948.
Cadogan A, Laslett M, Hing W, et al. Interexaminer reliability of orthopaedic special tests used in the assessment of shoulder pain. Man Ther. 2011;16(2): 131-135.
Walsworth MK, Doukas WC, Murphy KP, et al. Reliability and diagnostic accuracy of history and physical examination for diagnosing glenoid labral tears. Am J Sports Med. 2008;36:162-168.
Hegedus EJ, Goode AP, Cook CE, et al. Which physical examination tests provide clinicians with the most value when examining the shoulder? Update of a systematic review with meta-analysis of individual tests. Br J Sports Med. 2012;46(14):964-978.
Gill HS, El Rassi G, Bahk MS, et al. Physical examination for partial tears of the biceps tendon. Am J Sports Med. 2007;35:1334-1340.
Liu SH, Henry MH, Nuccion SL. A prospective evaluation of a new physical examination in predicting glenoid labral tears. Am J Sports Med. 1996;24: 721-725.
Netter’s Orthopaedic Clinical Examination An Evidence-Based Approach 3rd Edition Book.
Clinical Tests for the Musculoskeletal System, Third Edition book.
Mark Dutton, Pt . Dutton’s Orthopaedic Examination, Evaluation, And Intervention, 3rd Edition Book.
Millers Review of Orthopaedics, 7th Edition.