Feiss line test
- Fysiobasen
- Sep 15
- 2 min read
The Feiss Line Test is a simple clinical method used to evaluate the medial longitudinal arch of the foot by drawing an imaginary line through key anatomical structures. This test helps physiotherapists identify biomechanical deviations of the foot, particularly pronation (inward rotation) and supination (outward rotation). It is often used as part of a broader clinical assessment of foot function and load adaptation.
Background and Principle
The test is based on a line drawn from the medial malleolus (inner ankle) through the navicular tuberosity (a bony prominence on the medial side of the foot) to the head of the first metatarsal (base of the great toe). This line represents an ideal reference for the medial longitudinal arch in a normal position.
If the navicular tuberosity falls below the line during weight-bearing, it may indicate a weakened or collapsed arch (pes planus).
If the navicular tuberosity is positioned above the line, it may indicate a high arch (pes cavus).
Execution
The patient stands barefoot with weight evenly distributed on both legs.
The examiner marks three landmarks: the medial malleolus, the navicular tuberosity, and the head of the first metatarsal.
A straight line is drawn from the medial malleolus through the navicular tuberosity to the head of the first metatarsal.
If the line passes through or near the navicular tuberosity, it suggests a normal arch.
If the navicular tuberosity lies below the line, it suggests pes planus.
If the navicular tuberosity lies above the line, it suggests pes cavus.
Interpretation of Results
Normal: Line passes through or near the navicular tuberosity
Pes planus: Navicular tuberosity lies below the line
Pes cavus: Navicular tuberosity lies above the line
Advantages and Limitations
The Feiss Line Test is quick and easy to perform, providing an indication of the medial longitudinal arch of the foot. It is useful as part of a comprehensive foot examination but should be combined with other clinical tests to establish a reliable diagnosis. The reliability of the test may be influenced by individual anatomical variations and the accuracy of landmark marking.
Summary
The Feiss Line Test is a simple and effective clinical method for assessing the medial longitudinal arch of the foot. By observing the position of the navicular tuberosity relative to a reference line, clinicians can identify flatfoot (pes planus) or high arch (pes cavus). While practical and fast, the test should always be used in combination with other assessments for accurate diagnosis.
Sources
Hannigan-Downs K, Harter R, Smith G. Radiographic validation and reliability of selected clinical measures of pronation. J Ath Tr 2000; 35:12-30.
Medical Dictionary, 2009 Farlex and Partners. https://medical-dictionary.thefreedictionary.com/Feiss+line
Gjennomgått - Trukket
Feiss HO. A simple method of estimating the common varitions and deformities of the foot. 1. The American Journal of the Medical Sciences (1827-1924). 1909 Aug 1;138(2):213.
