Lengthening of the conjoined tendon of the gastrocnemius aponeurosis and soleus fascia is frequently used in the treatment of equinus deformities in children and adults. The Vulpius procedure as described in most orthopaedic texts is a division of the conjoined tendon in the shape of an inverted V. However, transverse division was also described by Vulpius and Stoffel, and has been reported in some clinical studies.
We studied the anatomy and biomechanics of transverse division of the conjoined tendon in 12 human cadavers (24 legs). Transverse division of the conjoined tendon resulted in predictable, controlled lengthening of the gastrocsoleus muscle-tendon unit. The lengthening achieved was dependent both on the level of the cut in the conjoined tendon and division of the midline raphé. Division at a proximal level resulted in a mean lengthening of 15.2 mm (sd 2.0, (12 to 19), which increased to 17.1 mm (sd 1.8, (14 to 20) after division of the midline raphé. Division at a distal level resulted in a mean lengthening of 21.0 mm (sd 2.0, (18 to 25), which increased to 26.4 mm (sd 1.4, (24 to 29) after division of the raphé. These differences were significant (p < 0.001).
Cite this article: Bone Joint J 2014; 96-B:778–82.
M. Sheedy typed the manuscript and Dr J. Matussek provided the English translation of Vulpius’ 1913 paper.
No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.
This article was primary edited by G. Scott and first proof edited by D. Rowley.
Supplementary material. Three videos showing pre- and post-operative functional outcome and corresponding graphs showing kinematic traces and moments and powers are available alongside the electronic version of this article on our website www.bjj.boneandjoint.org.uk
- Received December 19, 2013.
- Accepted February 21, 2014.
- ©2014 The British Editorial Society of Bone & Joint Surgery