Anterior Drawer Test of the Ankle

Anterior Drawer Test of the ankle is performed to estimate the stability of the anterior talofibular ligament (ATFL).

See Also: Ankle Anatomy

How do you perform an anterior drawer test of the ankle?

• The ankle drawer test is performed with the patient seated at the end of the bed or lying supine with their knee flexed to neutralize the pull of the gastrocnemius – soleus muscles and the foot supported perpendicular to the leg.
• With the ankle joint held at 10 to 15° of plantar flexion, the examiner grasps around the heel with one hand and stabilizes the tibia from the anterior side with the other.
• After asking the patient to relax the muscles, the examiner pulls the heel forward while continuing to stabilize the tibia with the other hand.

The anterior drawer test of the ankle may be performed with the patient supine, but the knee must be kept in a minimum of 30° flexion to eliminate the influence of the gastrocnemius muscle. The tibia can be pushed posteriorly as the calcaneus is drawn anteriorly.

See Also: Posterior Drawer Test of the ankle

What does a positive Anterior Drawer Test of the ankle mean?

• In the presence of a rupture of the anterior talofibular ligament, usually combined with injury to the capsule, the talus, and with it the foot, rotates anteriorly out of the ankle mortise around the intact medial (deltoid) ligament of the ankle, which serves as the center of rotation.
• The test suggests talofibular instability as a result of rupture of the anterior talofibular ligament ATFL.

The talus slides anteriorly from under the ankle mortise compared with the opposite side (assuming it is stable).There may be an appreciable “clunk” as the talus subluxates and relocates, and/or the patient may describe pain.

Ankle Anterior Drawer Test Accuracy

A Prospective, blinded, diagnostic-accuracy study by Theodore Croy to investigate the accuracy of the anterior drawer test of the ankle in patients with lateral ankle sprain, he found that the ankle anterior drawer test provides limited ability to detect excessive anterior talofibular ligament (ATFL) injury, the sensitivity and specificity was as following:

• Sensitivity: 74 %
• Specificity: 38 %

A study on 66 patients with history of lateral ankle sprain and 20 healthy controls, the sensitivity and specificity was 33% and 73%, respectively.

However, it may provide useful information when used in side-to-side ankle comparisons and in conjunction with other physical exam procedures, such as palpation.

The ATFL can be palpated two to three finger-breadths anteroinferior to the lateral malleolus. This is usually the area of most extreme tenderness following an inversion sprain. The anterior aspect of the distal tibiofibular syndesmosis may also be tender following this type of sprain.

Van Dijk et al. reported that when the combination of pain on lateral ligament palpation, hematoma formation of the lateral ankle, and a positive anterior drawer test were used a lateral ligament lesion was correctly diagnosed in 95% of cases.

Notes

This test has limited reliability, particularly if it is negative or if it is performed without anesthesia in the presence of muscle guarding.

It has been reported that 4 mm of laxity in the ATFL, resulting from posttraumatic attenuation or fibrosis, will give a clinically apparent anterior drawer (2 mm is normal) (false positive findings may be seen in up to 19% of uninjured ankles in those with ligamentous laxity).

Pain or apprehension can result in the patient contracting the triceps surae, thereby producing false-negative results. Do not apply overpressure in an attempt to overcome this response.

The anterior drawer test is useful in differentiating an intact ATFL from an isolated ATFL sprain but is less sensitive in differentiating an ATFL sprain from a more diffuse lateral ankle sprain involving the CFL.

In dorsiflexion, the Posterior Talofibular Ligament (PTFL) is maximally stressed, and the Calcaneofibular ligament (CFL) is taut, whereas the ATFL is loose. Conversely, in plantarflexion, the ATFL is taut, and the CFL and PTFL become loose.

The strength of the ankle ligaments from weakest to strongest is the ATFL, PTFL, CFL, and deltoid complex.

Tohyama et al. reported that a relatively low anterior load (30 N) during this test was more sensitive than a higher load (60 N) in distinguishing a significant distance between injured to normal anterior displacement. This seemingly occurs because a greater load would tend to elicit a protective muscle contraction that could mask the anterior talar displacement.

Related Anatomy

Anterior Talofibular Ligament:

• This thickening of the anterior capsule extends from the anterior surface of the fibular malleolus, just lateral to the articular cartilage of the lateral malleolus, to just anterior to the lateral facet of the talus and to the lateral surface of the talar neck.
• The anterior talofibular ligament (ATFL) is an intracapsular structure and is approximately 2–5-mm thick and 10–12-mm long.
• The ATFL functions to resist ankle inversion in plantarflexion. Regardless of ankle position, the ATFL is usually the first ankle ligament to be torn in an inversion injury.
• The accessory functions of the ATFL include providing resistance against anterior talar displacement from the mortise and resistance against internal rotation of the talus within the mortise.
• The ATFL requires the lowest maximal load to produce failure of the lateral ligaments, although it has the highest strain of failure in that group

References

1. Croy T, Koppenhaver S, Saliba S, Hertel J. Anterior talocrural joint laxity: diagnostic accuracy of the anterior drawer test of the ankle. J Orthop Sports Phys Ther. 2013 Dec;43(12):911-9. doi: 10.2519/jospt.2013.4679. Epub 2013 Oct 30. PMID: 24175608.
2. van Dijk CN, Lim LS, Bossuyt PM, Marti RK. Physical examination is sufficient for the diagnosis of sprained ankles. J Bone Joint Surg Br. 1996 Nov;78(6):958-62. doi: 10.1302/0301-620x78b6.1283. PMID: 8951015.
3. Landeros O, Frost HM, Higgins CC. Post-traumatic anterior ankle instability. Clin Orthop Relat Res. 1968 Jan-Feb;56:169-78. PMID: 5652775.
4. Colville MR, Marder RA, Boyle JJ, et al: Strain measurement in lateral ankle ligaments. Am J Sports Med 18:196–200, 1990
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6. TohyamaH, Beynnon BD, Renstrom PA, et al: Biomechanical analysis of the ankle anterior drawer test for anterior talofibular ligament injuries. J Orthop Res Official Publ Orthop Res Soc 13:609–614, 1995.
7. Frost HM, Hanson CA: Technique for testing the drawer sign in the ankle. Clin Orthop 123:49–51, 1977.
8. Tohyama, H, et al: Anterior drawer test for acute anterior talofibular ligament injuries of the ankle: how much load should be applied during the test? Am J Sports Med, 31:226, 2003.
9. Vela, L, Tourville, TW, and Hertel, J: Physical examination of acutely injured ankles: an evidence-based approach. AthlTher Today, 8:13, 2003.
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