Jack’s Test

Jacks Test (or the Hubscher maneuver) is a clinical test claimed to be an estimation of the efficacy and integrity of the windlass mechanism of the foot.


Jack’s test

Some debate as to who first described the test: Jack or Hubscher?

Ewen A. Jack described his test of dorsiflexion of the hallux in 1953 in the British edition of the Journal of Bone and Joint Surgery. Even more surprising, and empowering, is that he originally presented the paper in 1951 at a scientific meeting, a full five years before Enklaar’s discussion on Hubscher maneuver.

Jack, Ewen A. “Naviculo-cuneiform fusion in the treatment of flat foot.” J Bone Joint Surg Br 35 (1953): 75-82.

Link to PDF of paper

A simple test referred to as the ‘ toe-raising test ‘ gives an indication hut is not entirely reliable. While the patient stands with weight on both feet, the great toe is fully dorsiflexed. This manoeuvre restores the arch and gives stable posture in all cases of naviculo-cuneiform break, and in most combined breaks, but it does not do so when the talus is perpendicular. There is then insufficiemt leverage to force the navicular under the head of the talus. The efficiency of the toe-raising test is vitiated by a tight tendo calcaneus-an element in the deformity to l)e mentioned later. An interesting anatomical point emerges in connection with this toe-raising test. If the long arch is incompetent for any reason, the foot rolls medially and the calcaneum becomes everted at the subtalar joint. Eversion is not a pure movement in one plane, but is associated with rotation about the head of the talus, and produces a valgus position of the foot in relation to the vertical axis of the talus. Therefore even when the arch sags at the naviculo-cuneiform joint alone, the valgus element of the flat-foot deformity is produced at the talo-navicular joint. But it is a normal movement, in a normal joint. Toe raising, by restoring the vertical arch, automatically corrects the valgus.

jacks paper

Ewen Jack’s Original Publication

Jack's original description of the test

Jack’s original description of the test

Jacks original x-rays showing the Toe Raising test

Jacks original x-rays showing the Toe Raising test

need to address this



Research that Used Jacks Test:

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Page last updated: Jun 28, 2022 @ 10:42 pm

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