The tibialis posterior has the most complex foot insertion of any tendon, with slips to the navicular, all three cuneiforms, the cuboid, and three metatarsal bases. This broad fan-like attachment distributes arch support forces across the entire medial column and midfoot. PTTD typically tears the navicular slip first (the largest and most loaded component), while the accessory slips may remain intact and partially preserve arch height even in advanced stages.
| Muscle | |
|---|---|
| Attachment | The tibialis posterior has a broad fan-like insertion with multiple slips: primary insertion on the navicular tuberosity; secondary slips to the sustentaculum tali, the three cuneiforms, the cuboid, and bases of the 2nd-4th metatarsals |
The fan-like insertion distributes the medial arch support force across the entire midfoot; the primary navicular slip is the functional anchor; accessory slips maintain the transverse and longitudinal arch relationships
MRI of PTTD shows signal abnormality and thinning of the primary navicular slip first, followed by progressive failure of the secondary slips. FDL tendon transfer to the navicular replaces the function of the primary slip, while intact secondary slips may help maintain midfoot stability. Acute avulsion of the primary slip from the navicular is uncommon compared with gradual degeneration and is treated by reattachment with suture anchors. The accessory navicular (an accessory ossicle at the navicular tuberosity in 10-12% of the population) is the site of accessory navicular syndrome where the medial tibialis posterior slip pulls on the ossicle.
Tibialis posterior medial slip avulsion or stress reaction at the accessory navicular producing medial foot pain managed with orthotics and surgical excision for refractory cases.
This website uses cookies to enhance your experience. Some are essential for site functionality, while others help us analyze and improve your usage experience. Please review your options and make your choice.
If you are under 16 years old, please ensure that you have received consent from your parent or guardian for any non-essential cookies.
Your privacy is important to us. You can adjust your cookie settings at any time. For more information about how we use data, please read our privacy policy. You may change your preferences at any time by clicking on the settings button below.
Note that if you choose to disable some types of cookies, it may impact your experience of the site and the services we are able to offer.
Some required resources have been blocked, which can affect third-party services and may cause the site to not function properly.
This website uses cookies to enhance your browsing experience and ensure the site functions properly. By continuing to use this site, you acknowledge and accept our use of cookies.
