Rent Test | Transdeltoid Palpation

The Rent Test (or Transdeltoid Palpation test) is used to diagnosis the full thickness tear of the shoulder rotator cuff. It’s first described by Codman in 1934.

When performed correctly, Codman suggested that clinicians could locate a point of tenderness and detect a sensation “crepitus” underneath their fingers which would therefore suggest the presence of a rotator cuff tear.

How do you perform the Rent Test?

• The patient sits or stands with the involved arm relaxed and hanging on the side.
• The clinician stands behind the patient and holds the patient’s distal arm with the patient’s elbow flexed to 90 degrees.
• The clinician then passively moves the patient’s glenohumaeral joint into full extension, which allows greater palpation of the humeral head and tendons inserting into the greater tuberosity.
• Palpation is performed at the anterior margin of the acromion. While palpating this area with the shoulder in the fully relaxed and extended position, the clinician moves the patient’s arm into internal and external shoulder rotation to allow further palpation of the rotator cuff tendons.

What does a positive Rent Test mean?

In the presence of a complete rotator cuff tear, the eminence of the greater tuberosity appears quite prominent to palpation, and the torn area feels like a sulcus “rent”, or soft-tissue defect (depression of approximately 1 finger-width) that has avulsed from the tuberosity.

Palpating the anterior and posterior margins of the cuff tear may elicit an avulsed edge.

It is recommended that this test be used to determine the absence or presence of a rotator cuff tear rather than the size of the tear.

Sensitivity & Specificity

One study by Wolf ¹ to assess the diagnostic accuracy of transdeltoid palpation (the rent test) for the diagnosis of full thickness rotator cuff tear, Transdeltoid palpation was found to have a:

• Sensitivity: 95.7%
• Specificity: 96.8%

Lyons and Tomlinson calculated a sensitivity of 91 % and a specificity of 75 % after performing the test during strength testing in a series of 45 patients.

Ponce et al. performed the examination in 63 patients who presented with shoulder pain and compared the results to a standardized MRI sequence. Their results suggest that the rent test was more valuable in the detection of full-thickness tears when compared to any of the partial-thickness tears. In addition, sensitivity and specificity values appeared to increase with increasing patient age: sensitivities were >75 % and specificities approached 100 % for patients older than 55 years of age whereas the test was less predictive in younger patients (sensitivity of 43 % and specificity of 70 %).

Notes

With the arms initially at the side, the examiner palpates the area just beneath the anterolateral acromion and lateral to the coracoacromial ligament which also corresponds to an anatomically thin area of the deltoid, possibly facilitating the detection of a tendon defect.

When the arm is at the side, this location is referred to as “Codman’s point” where the anterior supraspinatus tendon inserts on the greater tuberosity. During palpation, the patient’s arm is simultaneously moved through a range of motion, generally involving a combination of slight abduction and extension along with internal and external rotation.

At approximately 10° of internal rotation, the examiner can identify the bicipital sheath and the lesser tuberosity, thus providing information regarding spatial orientation. Extension of the shoulder may allow additional palpation of the anterior infraspinatus.

References

1. Wolf EM, Agrawal V. Transdeltoid palpation (the rent test) in the diagnosis of rotator cuff tears. J Shoulder Elbow Surg. 2001 Sep-Oct;10(5):470-3. doi: 10.1067/mse.2001.117126. PMID: 11641706.
2. Codman EA. The shoulder: rupture of the supraspinatus tendon and other lesions in or about the subacromial bursa. Chap. 5. Boston: Thomas Todd; 1934. p. 123–77.
3. Ponce BA, Kundukulam JA, Sheppard ED, Determann JR, McGwin G, Narducci CA, Crowther MJ. Rotator cuff crepitus: could Codman really feel a cuff tear? J Shoulder Elbow Surg. 2014;23(7): 1017–22.
4. Lyons AR, Tomlinson JE. Clinical diagnosis of tears of the rotator cuff. J Bone Joint Surg Br. 1992;74(3):414–5
5. Dutton’s Orthopaedic Examination, Evaluation, And Intervention 3rd Edition.