L is for the Lachman Test

August 18, 2023

The Lachman’s Test or dorsal plantar drawer test is for testing an unstable toe, particularly in those with a plantar plate tear.

The Lachman’s Test, also known as the dorsal-plantar drawer test when applied to the toe, is a clinical maneuver used to assess instability at the metatarsophalangeal (MTP) joint, particularly the second toe. This test is especially useful in evaluating injuries related to the plantar plate — a fibrocartilaginous structure that plays a critical role in stabilizing the MTP joint and preventing dorsiflexion beyond the normal range. Damage or tearing of this plate often results in symptoms like toe instability, pain at the ball of the foot, and, in chronic cases, visible toe deformity such as hammertoe or crossover toe.

To perform the Lachman’s Test for the toe, the examiner stabilizes the metatarsal head with one hand while the proximal phalanx is grasped and moved dorsally and plantarly with the other hand. The goal is to detect any excessive movement or “drawer” motion that would indicate joint laxity. In a healthy plantar plate, this motion is minimal and firm. However, in the presence of a plantar plate tear, the proximal phalanx will move dorsally with a softer, less resistant end feel, often compared to the drawer sign in knee injuries. The degree of movement can help grade the severity of the tear, which is important for guiding treatment decisions.

This test is particularly valuable because plantar plate tears can be subtle and often missed in early stages without focused examination. Radiographs may not clearly show soft tissue injuries, and MRI, while helpful, is not always definitive or immediately available. Therefore, clinical evaluation with Lachman’s Test plays a pivotal role in early detection and management. When positive, this test supports a diagnosis of plantar plate injury and can prompt timely conservative management or surgical referral, especially in athletes or individuals whose daily activities rely heavily on forefoot function.

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