Assessment Of A TMT Joint Injury
Assessment Signs And Tests That Can Indicate TMT Joint Injury:
- Tenderness to palpation of the midfoot when pressure is applied.
- Bruising along the bottom of the foot.
- Pain with a stress examination of the midfoot.
- Pain with a stress examination test to the midfoot known as the “piano key” test puts stress across the midfoot and will generally produce pain if there is a TMT joint injury.
- Single leg heel raise. When asked to stand on one foot (going on to tip toes) significant stress is placed across the midfoot and again will generally cause pain if there is a TMT joint injury.
Investigations Used To Help Diagnose A TMT Joint Injury
An X-ray can visualize the alignment of the Lisfranc joint, picking up any change in the normal joint alignment when compared to the unaffected side. If a change in joint alignment when compared to the uninjured foot is present it suggests injury to the ligaments of the midfoot. In low energy sporting injuries for example there may not be any fractures and only damage to the soft tissue supportive structures of the TMT joint has occurred. In this situation taking a weight bearing X-ray is ideal for visualizing the alignment under load (if standing on the injured foot can be tolerated). See Image Below.
With high energy injuries such as those sustained in a motor vehicle accident, X-rays are useful as the can also pick up fractures at the TMT Joint complex. These injuries can be a Lisfranc fracture-dislocation involving multiple joints and including multiple fractures of the area.
MRI And CT Imaging For TMT Joint Injury
The use of Magnetic resonance imaging (MRI) scan can better visualize the soft tissues injured in a TMT joint injury but these investigations aren’t always necessary to diagnose however are often used if standard X-rays are inconclusive. Similarly for CT imaging (Computerized Tomography Scan), where this sort of imaging is more detailed than a standard X-ray and can create cross-section images of the foot meaning examination via CT imaging may show unsuspected associated fractures missed by X-ray. Yet again is not always necessary to correctly diagnose a Lisfranc injury.
The treating orthopaedic surgeon will order the necessary investigations, most likely where possible a weight bearing X ray will be ordered and then a MRI or CT scan as deemed necessary depending on the results of the X-rays and the surgeons management strategy based on the severity of the injury.
Disclaimer: Sydney Physio Clinic provides this information as an educational service and is not intended to serve as medical advice. Anyone seeking specific advice or assistance on Diagnosis And Treatment Of TMT Joint Injury should consult his or her physiotherapist, general practitioner, sports medicine specialist or orthopaedic surgeon.