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SPRING LIGAMENT
•  Normally the hindfoot stability and maintenance of the medial
longitudinal arch rely on both dynamic and static stabilizers.
•  Spring ligament is an important static stabilizer for the
longitudinal arch of the foot (in conjuntion with the plantar
fascia and the superficial fibers of the deltoid ligament).
•  The main dynamic stabilizer of the ankle is the posterior tibial
tendon (PTT).
•  The spring ligament (plantar calcaneonavicular ligament)
serves as a stringlike structure, wrapping under the talar head
from its calcaneal origin to its navicular insertion.
•  When this ligament fails the result is the so-called pes
planovalgus deformity or adult-acquired flatfoot deformity.
Components of Spring ligament
The spring (calcaneonavicular) ligament
complex forms the medial and plantar
margins of the articular cavity of the head
of the talus and has 3 components.
v The superomedial is the strongest
component.
q The inferoplantar longitudinal.
ü The medioplantar oblique.
Components of Spring ligament
The superomedial fascicle extends from the sustentaculum
tali to the dorsal aspect of the medial navicular. The posterior
tibial tendon lies immediately superficial.
This component is usually seen on routine axial and coronal MR
images. Axial oblique images of the ankle are also helpful
q 
q  The inferoplantar layer extends from the coronoid fossa of
the calcaneus just anterior to the sustentaculum tali and
inserts at the the inferior beak of the navicular.
This component may be seen on coronal routine protocol
sequences and particularly performing axial oblique images
q  The medioplantar component originates at the coronoid fossa
of the calcaneus just anterior to the inferoplantar and has a
medial oblique course attaching at the medioplantar
navicular, just plantar to the navicular tuberosity.
It is seldom seen on a routine MR images and it is usually
necessary to perform transverse oblique images.
Original anatomic illustration of the Spring ligament complex
demonstrating their 3 fascicular components with its insertion sites.
Original anatomic illustration showing the 3 ligament layers of the Spring
ligament complex
MRI protocols
•  We strongly suggest the application of 1.5 or 3
Tesla scanners.
•  We perform a routine ankle protocol including
axial, sagital and coronal T1, T2 and DP FS or
STIR sequences with 4-mm slice thickness and
0.4 mm spacing.
•  We also add transverse oblique images along the
sagital plane in order to improve the recognizion of
the 3 componentes. If neccessary, we also sum up
thin slices.
Superomedial portion of Spring ligament complex. STIR
weighted axial and sagittal sequences. This fascicle is seen
immediately deep to the posterior tibial tendon (arrows)
Inferoplantar longitudinal component of the spring ligament
complex. Fat suppressed T2 weighted axial oblique image.
Medioplantar oblique layer of the spring
ligament complex. T1 weighted axial
oblique image.
TIBIOSPRING LIGAMENT
The tibiospring ligament is the
anterior, superficial portion of the
deltoid ligament complex and fuses
with the superior margin of the
superomedial layer.
PTT
SML
STIR weighted coronal image and original
anatomic illustration showing the posterior
tibial tendon and its relations with the
superomedial fascicle and the tibiospring
component (red arrow)
Clinicalpresenta-on
•  Spring ligament injuries have a high association with
posterior tibial tendon tears. They are also most
commonly seen in middle-aged women and as a result
of chronic degeneration.
•  Early in the disease process, patients may complain of
activity-related pain at the medial ankle and difficulty
with balance. Later they mention activity related pain
around the sinus tarsi and lateral malleolus,
presumably because of impingement of lateral
structures. With the development of subtalar
osteoarthritis; pain, stiffness, and swelling are present.
•  Isolated as well as acute injuries of the spring ligament
are extremely rare
Pathology of the Spring ligament complex
•  The superomedial (SM) is the most important spring ligament
component for providing functional stability of the arch and is also the
most frequently injured.
•  In almost all instances accompanying posterior tibial tendon
abnormalities are present.
•  Published reports give a mean thickness for the SM ranging from 2.5
mm to 4.7mm. In pathologic states it frequently thickens to a level
greater than 5 mm.
•  The most specific finding of a ligament tear is a fluid-signal filled
discontinuity of the ligament on T2 or STIR-weighted sequences,
representing a tear through the full thickness. They most commonly
occur at the distal or proximal attachment sites.
•  The inferoplantar and medioplantar components are less frequently
torn. Of the two, the medioplantar is more susceptible to injury due to
its close proximity to the SM.
Pathology of SM fascicle of SLC.
T2 FS weighted axial and coronal images
demonstrates an abnormally lax and thickened
superomedial layer along its anterior fibers (arrows).
There is also thickening of PTT with increase fluid
within the tendon sheath (red arrows).
A)
B)
Pathology of SM fascicle of SLC.
A) 
STIR weighted axial image showing superomedial layer thickening and
with signal intensity changes (arrow).
B) 
T2 FS weighted axial image shows similar changes (arrow). Bone marrow
edema within the head and body of the astragalus with microtrabecular
fractures are also visible (red arrows).
Discontinuity of the Spring ligament.
STIR weighted axial image showing
the superomedial portion diffusely
thinned and with a tear at the level of
the astragalus neck (arrow). PTT is
also affected (red arrow)
Avulsion-Tear of superomedial fascicle.
PD FS Axial oblique sequence using thin
slices showing this layer being detached and
thinned near its insertion at the navicular
bone (arrow).
It is associated with a thickened posterior
tibial tendon within a partial tear along the
deep surface (arrowhead)
Avulsion-Tear of PTT with normal Spring ligament
complex.
PD FS and T1weighted axial oblique sequences
using thin slices demonstrate abnormal thickening
and increased signal intensity of the PTT (white
arrow) with an avulsion tear at the level of its distal
insertion (blue arrow)
There is a normal appearance of the superomedial
portion of the spring ligament (red arrows), which
is seen deep to the posterior tibial tendon.
SUMMARY
•  Posterior tibial tendon tears are a frequent cause of flatfoot
deformity. Nevertheless, in many cases, an associated tear of the
spring ligament is present.
•  Spring ligament tears usually involve the superomedial
calcaneonavicular ligament portion, which is the most important
static stabilizer of the longitudinal arch.
•  MRI is the modality of choice providing optimal visualization of the
spring ligament, having to perform to its best definition specific
sequences.
•  Proper knowledge of anatomy of the spring ligament complex
enables the careful MR reader to diagnose its pathology and
relation with other structures.
•  This in turn allows the surgeon to provide a more complete and
functional repair of the longitudinal arch.