The flexor retinaculum of the hand is a fibrous structure forming the carpal tunnel in conjunction with the carpal bones. To prevent incomplete release of the carpal tunnel it is of benefit to know about the expected longitudinal expansion of the flexor retinaculum. The objective of the present study was to identify a possible correlation between the proximodistal expansion of the flexor retinaculum and the length of the hand.

We conducted an anatomical study on 124 hands of 62 body donors. The hand length and the length of the flexor retinaculum were measured in millimeters. By dividing the length of the flexor retinaculum by the hand length an individual ratio was calculated.

The mean length of the observed hands was 187.8 mm. The mean proximodistal length of the flexor retinaculum was 27.2 mm (range, 14−39 mm). A positive correlation was noted between the proximodistal length of the flexor retinaculum and length of the hand (p = 0.01). On average, the length of the flexor retinaculum corresponded to 14% (range, 8–20%) of the hand length in right hands versus 15% (range, 11–20%) in left hands.

A greater proximodistal length of the flexor retinaculum in longer hands compared to shorter hands can be expected. The length of the flexor retinaculum corresponds to 14–15% of the length of the hand. However, one should be aware that the length of the flexor retinaculum extends as far as 20 % of the length of the hand.

手的屈肌支持带是一种纤维结构，与腕骨一起形成腕管。为了防止腕管不完全释放，了解屈肌支持带的预期纵向扩张是有益的。本研究的目的是确定屈肌支持带的近端扩张与手的长度之间可能存在的相关性。

我们对 62 名捐献者的 124 只手进行了解剖研究。以毫米为单位测量手的长度和屈肌支持带的长度。通过将屈肌支持带的长度除以手的长度来计算个体比率。

观察到的手的平均长度为 187.8 毫米。屈肌支持带的平均近端长度为 27.2 毫米（范围，14-39 毫米）。屈肌支持带的近端长度与手的长度呈正相关（p = 0.01）。平均而言，右手屈肌支持带的长度相当于手长的 14%（范围，8-20%），而左手的长度为 15%（范围，11-20%）。

与较短的手相比，较长的手的屈肌支持带的近端长度可以预期更大。屈肌支持带的长度相当于手长的 14-15%。但是，应该注意屈肌支持带的长度可延伸至手长度的 20%。