Thoracolumbar spine x-rays

Cite this article as:
Tessa Davis. Thoracolumbar spine x-rays, Don't Forget the Bubbles, 2019. Available at:
https://doi.org/10.31440/DFTB.17581

Read our step-by-step guide to interpreting thoracic and lumbar spine x-rays.

Thoracolumbar spine x-ray involves two views – AP and lateral.

 

  1. Check it’s an adequate view

For a lumbar spine view

  • you should be able to see L1-L5 but also the full T12 vertebral body, T11/12, and the sacrum on the AP view
  • the vertebral bodies, facet joints, and pedicles should be clearly visible on the lateral view
  • the transverse processes should also be visible (and are often obscured by gas)

For the thoracic spine view

  • make sure the whole thoracic spine is visible
  • you should be able to see the pedicles, spinous processes, and vertebral bodies
  • the ribs can cause difficulty seeing the thoracic spine on a lateral view

 

2. Know your anatomy

  • Clavicle is at T3
  • Tracheal bifurcation is T4/5
  • 12th rib is at T12
  • In the lumbar spine, the disc spaces also increase in size, although note that the L5/sacral space is narrower than the L4/L5 space

From https://www.wikiradiography.net/

3. Check the alignment

On the AP check that the vertebral bodies and spinous processes are aligned. On the lateral, check the alignment of the vertebral bodies.

 

 

4. Look for loss of vertebral height

In the thoracic spine, the vertebral bodies (and the disc spaces) should gradually increase in size as you get further down the spine.

Check all the vertebral bodies looking specifically for loss of height. This indicates a compression fracture.

 

 

 

5. Look for widened inter-spinous or inter-pedicle distance and check the processes

In the lumbar spine check that all the pedicles, spinal, and transverse processes are intact.

See below (under burst fracture) for an example of widened inter-pedicle distance and (under Chance fracture) widened spinous process process distance.

Transverse process fracture From https://www.imageinterpretation.co.uk/thoracolumbar.php

 

6. Check for translation/rotation or distraction

Translation or rotation is displacement in horizontal plane; and distraction is displacement in the vertical plane.

Translation/rotation is due to a side-to-side motion (can be left-to-right or front-to-back). It is a serious injury and always involves the posterior ligamentous complex.

Distraction is where the vertebrae are pulled apart and carries a high risk of cord injury. Often there is compression at the other side (see Chance fracture below).

 

7. Know the common types of fractures

Compression fracture

This is the most common type of fracture and is identified through loss of vertebral height (see number 4 above). It involves one column only and is a stable fracture.

 

Burst fracture

On x-ray alone 25% of burst fractures are misdiagnosed as vertebral compression fractures. A burst fracture is where there is a compression, but part of the vertebral body has been projected out anteriorly.

On AP view there will be an increased interpedicular distance in 80% of burst fractures.

On lateral view there will be reduced vertebral height and disrupted anterior alignment.

A burst fracture involves two columns and is usually considered to be unstable.

 

Chance fracture

Usually from a seatbelts injury and is commonly at L2/L3

This is a flexion-distraction injury where there is horizontal splitting of the vertebral body with ligament rupture. This is an unstable fracture and involves all three columns

Sometimes there is increased distance between the spinous processed on the lateral view (but not always).

On the AP view there can be increased distance between the spinous processes at the level of the Chance fracture.

 

Jumper’s/lover’s fracture

So-called because it’s usually from people jumping out of windows to escape the police or angry partners. This is severe axial loading leading to compression/burst fractures alongside a calcaneus fracture.

https://radiopaedia.org/articles/lovers-fracture-2?lang=us

References

Radiopaedia

Radiology Assistant

Norwich Image Interpretation Course

Radiology Masterclass

Foot x-rays

Cite this article as:
Tessa Davis. Foot x-rays, Don't Forget the Bubbles, 2018. Available at:
https://doi.org/10.31440/DFTB.12924

1. Check you have the right views. There are two views in foot x-rays DP (dorsal-plantar) and oblique. Both should ideally be done when weight-bearing if your patient can manage it.

 

2. Review the bones. 

Work round the bones one by one (including the metatarsals). Start proximally and work your way down, going medial lateral. This will ensure you check them all.

 

3. Find any bits that aren’t attached. 

Consider whether any floaty bits might be an ossicle. Pay particular attention to small avulsions from the bones – these are very easy to miss.

There are a couple of common ossicles that you might see:

Os tibiale externum – this is an ossicle present at the medial aspect of the navicular bone (it appears at adolescence)

Os peroneum – this an accessory bone in the peroneus longus tendon

Avulsions commonly occur on:

The lateral aspect of the cuboid

The dorsal surface of navicular and talus (seen only a lateral ankle view)

4. Check the base of fifth.

Most fractures here are avulsions of the metatarsal tuberosity. This is where peroneus brevis attaches and an inversion injury can cause the fracture.

https://sprintforever.blogspot.co.uk/

A Jones fracture is a transverse fracture at the proximal shaft of the fifth metatarsal. It is managed differently (non-weight bearing).

Also, don’t confuse a base of fifth fracture with an unfused apophysis or vice versa. An unfused apophysis runs longitudinally, whereas fractures are usually transverse. The apophysis appears at age 12 for boys and age 10 for girls, and it usually fuses over the next few years.

https://radiopaedia.org/cases/fifth-metatarsal-apophysis

 

5. Check for calcaneus fractures. Look for an avulsion of the anterior process of the calcaneum (oblique view). Look lateral to the calcaneum where extensor digitorum brevis inserts (on the DP view). You can also get injuries to the anterio-lateral aspect of the calcaneus.

 

6. Check for Lisfranc injuries. Normally aligned bones should have the second metatarsal aligning with the intermediate cuneiform on the DP view; and the third metatarsal aligning with the lateral cuneiform on the oblique view. The Lisfranc ligament connects the cuneiforms and the second metatarsal. Disruption of this ligament leaves an unstable foot and so it’s an important one not to miss.

https://emergencymedicineireland.com/

https://emergencymedicineireland.com/

To see more about Lisfranc injuries, check out Andy Neill’s great video on this here.

 

7. Consider stress fractures

These commonly occur on the second or third metatarsals. Sometimes they just present with callous formation or sometimes cannot be seen on plain x-ray and require further imaging (e.g. MRI) to diagnose.

Ankle x-rays

Cite this article as:
Tessa Davis. Ankle x-rays, Don't Forget the Bubbles, 2016. Available at:
https://doi.org/10.31440/DFTB.9992

The ankle joint consists of three bones – the tibia, the fibula, and the talus.

The ankle also consists of two joints – the ankle joint (where the tibia, fibula and talus meet) and the syndesmosis joint (the joint between the tibia and fibula which is held together by ligaments).

There are three main sets of ligaments:

  • Medial: deltoid ligament
  • Lateral: posterior talofibular, anterior talofibular and calcaneofibular ligaments
  • Syndesmotic ligament

Ankle views

An x-ray of the ankle will have three views – AP, mortise, and lateral. It should be noted though, that in some countries, including the UK, only the mortise and lateral are used. See the annotated images below from WikiFoundry, and thanks also to Radiopaedia:

In the AP view:

  • The distal fibula should be slightly superimposed on the tibia
  • The lateral and medial malleoli should be in profile
  • The tibiotalar space should be open (although the full mortise isn’t visible)

In the mortise view:

  • This aims to assess the articulation of the ankle joint
  • The lateral and medial malleoli should be in profile
  • The mortise should be uniformly visible
  • The base of the fifth metatarsal should be included in the view

In the lateral view

  • The following bones can be assessed: tibia, fibula, talus, cuboid, navicular, calcaneus, and fifth metatarsal
  • The distal fibula should be superimposed by the posterior part of the distal tibia
  • The talar domes should be superimposed
  • The joint space between the tibia and the talus should be uniform

N.B. Assess each bone individually, and if you see a break in one, then look for a second break.

1. Trace around the tibia and fibula in both views.

Be mindful that an ankle fracture can be unstable and therefore it’s important not to miss them.

2. Pay particular attention to the fibula on the lateral view for an oblique fracture.

Oblique fracture (from Radiology Key)

3. Look at the mortise and the talar dome.

Make sure the space is uniform, and that the talar dome surface is smooth.

Osteochondral fracture (from Radiopaedia)

4. Look at the interosseous ligament.

Measure the gap between the tibia and the fibula 1cm proximal to the tibial plafond. It should be less than 6mm, otherwise consider a ligament rupture which could be associated with a fracture.

Image result for interosseous ligament rupture xray
Widened gap between tibia and fibula

5. On the lateral view trace the lateral and medial malleolus, the posterior tibia, the calcaneus, and the base of the 5th metatarsal.

6. Assess the Bohler’s angle

  • Draw two lines at tangents to the anterior and posterior aspects of the calcaneus
  • The angle should be 20-40°
  • If it’s less than 20° then consider a calcaneus fracture
Calcaneus fracture (from Radiopaedia)

7. Do a final check around the bones to make sure you haven’t missed anything the first time around.

8. Remember about accessory ossicles – they aren’t fractures!

  • There are three common accessory ossicles in the ankle: os trigunum (usually forms at 7-13 years old); os subtibiale (when the medial malleolus epiphysis fails to fuse with the tibia in the later teenage years); os subfibulare (can also be an unfused ossification centre or an avulsion fracture).

Common fractures and their management

The level of the fracture directs the treatment – fractures can be classified according to the Salter-Harris classification.

Lateral malleolus fracture

In children, a fibula fracture usually requires a short leg cast and six weeks of non-weight bearing. Salter-Harris I distal fibula fractures can be diagnosed if there is tenderness directly on the lateral malleolus (rather than the ligaments) and many recommend treating as a fracture even if no radiographic fracture is noted.

However, a study in JAMA carried out MRI scans on 135 children with presumed SH1 distal fibula fractures. All children were treated with a removable leg brace and advised to continue regular activities as tolerated. 4 of the children had an SH1 on MRI, 38 had an avulsion fracture, and the rest showed ligamentous injury or bony contusion. By 1 month, 72.1% had full weight-bearing activity and by 3 months 96.9% had returned to normal activities (it didn’t matter which type of injury they had on MRI). Therefore, a removable brace may be appropriate for a Salter Harris I, if your department stocks them. (See a full summary of this article on ALiEM).

Medial malleolus fracture

An undisplaced distal tibia (Salter-Harris I or II) can be managed with a long leg cast and non-weight bearing. SH3 or 4 needs discussion with ortho. All will have a fracture clinic follow up in a week or so.

Salter-Harris I distal tibia fractures can be diagnosed if there is tenderness directly on the medial malleolus (rather than the ligaments) and many recommend treating as a fracture even if no radiographic fracture is noted.

The most common distal tibial epiphysis injury is a Salter Harris II

The high occurrence of Salter-Harris III and IV fractures is because the lateral and deltoid ligaments insert here and they are stronger than the physis itself.

A Tillaux fracture is a Salter-Harris III but with avulsion of the anterolateral corner of the distal tibial epiphysis. If there is <2mm displacement then the patient can have a long leg cast, and be non-weight bearing, with ortho discussion and follow-up. If there is >2mm displacement then an ortho review will be required as typically this need operative management.

Pilon fracture

A pilon fracture is where there is an axial load on the tibia and the talus is pushed into the tibia plafond.

If the fracture is non-displaced or very distal, it is unlikely to require surgery. It would usually be treated with a short leg cast, and weight bearing would be avoided for six weeks.

If it is displaced or the ankle is unstable, then surgery may be required to avoid non-union, so speak to the ortho team.

Posterior malleolus fracture

Posterior malleolus fracture (from Wikiradiography)

Usually when this has happened, there is also a lateral malleolus fracture (because they share ligament attachments). The ankle can be unstable if a large piece is broken and therefore surgery may be indicated – so speak to the ortho team.

An untreated posterior malleolus fracture can lead to arthritis because of the disruption to the cartilage surface.

If the fracture is not displaced then it would usually be treated with a short leg cast, and weight-bearing would be avoided for six weeks.

Talar neck fracture

Talar neck fracture

This fracture carries a high risk of avascular necrosis.

If the fracture is non-displaced then it can be managed with a short leg cast or a boot. If it is displaced then surgery will be required.

Bimalleolar fracture

Bimalleolar fracture (from Radiopaedia)

If two parts of the malleoli are broken then the ankle is not stable and surgery is usually needed.

Trimalleolar fracture

Trimalleolar fracture (from Radiopaedia)

If all three malleoli are broken then there can be associated dislocation. The ankle will be unstable and will require ortho input.

Maisonneuve fracture

This fracture is uncommon in children but can occur. It is where there is a spiral fracture of the proximal fibula along with ankle instability. On x-ray there can be syndesmotic widening.

mason1
From Wheeles Online

In adults this can be managed with a long leg cast, but in children it will require operative fixation.

Syndesmotic injury

Overlap between the tibia and fibula in a syndestomic injury (thanks to Bone School)

The joint between the tibia and fibula are held together by ligaments. If this ligament is sprained then this is a syndesmotic injury.

As mentioned above, there can be widening of the clear space between the medial border of the fibula and the lateral border of the posterior tibia (>5mm). You can also get an overlap of the fibula and the anterior tibial tubercle (>6mm on the AP views, >1mm on the mort

When do I need an orthopaedic review immediately?

  • Open fracture
  • Salter-Harris III or IV
  • Neurovascular injury
  • Compartment syndrome
  • Unable to reduce the fracture

Ref: RCH

Should we be worried about growth plates?

Growth arrest doesn’t occur immediately after the injury, and can even occur in seemingly benign fractures. It can be delayed for up to 6 months and so it is important to follow up ankle fractures post-injury.

References:

Wheeles Online

Radiopaedia

Royal Children’s Hospital, Melbourne

Radiology Masterclass

(Ed: Thanks to Eyston Vaughan-Huxley for his input too).

Through the looking glass

Cite this article as:
Andrew Tagg. Through the looking glass, Don't Forget the Bubbles, 2016. Available at:
https://doi.org/10.31440/DFTB.9685

As we head out winter in the southern hemisphere the northern hemisphere can see that ‘Winter is Coming’ and with it the scourge of the paediatric emergency departments – bronchiolitis.  It’s one of those diseases that the we should all be able to spot but the real challenge is picking up those that present as if they have bronchiolitis but in fact have a different disease entity altogether.