Biomedical Engineering Reference
In-Depth Information
prosthesis has failed fixation and collapsed through the talar body, the talar
component and osteolytic bone needs to be removed. A “custom talar body
“prosthesis can be used to replace this severe bone loss. The 2 fixation stems of
this device must use the calcaneus for bony anchorage and stability in such cases.
If stability can be achieved with improved, wear resistant bearings, excellent
function can be restored. However, if alignment and stability cannot be achieved
with these custom implants, it is advisable to perform a calcaneal-tibial fusion for
long term stability and function. An example of restoration with a “custom talar
body” replacement is seen in Fig. 4.40.
4.6 Sample Case Histories
4.6.1 Case Report #1
New Jersey Cylindrical Total Ankle, (Fixed-bearing, cemented design for use with
intact malleoli and functioning or reconstructable collateral ligaments).
4.6.1.1 History
A 32 year old, 152 pound (68 kg), 5 foot 5 inch (160 cm) tall, Hispanic female
developed intractable weight bearing pain with crepitus and limited range of
motion in her right ankle (5
o
plantarflexion to 25
o
plantarflexion) over a 7 year
period, after sustaining a pilon fracture 11 yars prior, treated by ORIF with cast
immobilization. Her hindfoot alignment was neutral, and she had good collateral
ligament stability. Pre-operative X-rays revealed advanced post-traumatic arthritis
of the right tibio-talar joint with joint space loss and peripheral osteophytes on the
tibia and talus, Fig. 4.41.
Fig. 4.41
Lateral X-rays of a post-traumatic arthritic right ankle in a 32 year old woman
with intractable pain and limited range of motion
