Broken leg? Sprained ankle? Gone are the days of plaster casts for weeks on end, knitting needles stuck down dirty casts to get to that everlasting itch, and regular trips to the Outpatients Clinic for resizing of your temporary exoskeleton. Thanks a million, dear moonboot!
So called because of its resemblance to an astronaut’s boots, the moonboot has changed the face of post-operative and conservative treatment of fractures and sprains, as well as tendon and ligament repairs. Depending on the surgeon, you might go straight into a moonboot after a surgical repair of a broken bone or torn ligament, or you might go into a plaster cast for the first 2 weeks and then into the moonboot once the swelling has gone down enough and your x-rays have shown progress.
The moonboot has been designed and re-designed by so many companies, that it would be impossible to cover the details of all available styles and designs in this blog. We will look at the basic function of the boot and broadly categorize it based on the condition it is best suited for.
Designed for safe walking
In most cases, the main aim of the moonboot is to immobilize the ankle joint while still allowing the patient to use the leg during gait. The ankle is immobilized in a neutral 90deg position by locking the leg inside a rigid outer shell or frame that extends from the tips of the toes to just underneath the knee joint. Because the natural forward-rolling motion from a healthy ankle is now eliminated when walking, the sole of the moonboot is modified to compensate for that loss in movement. A rounded (rockerbottom) sole underneath the rigid shell or frame helps the patient roll over his midfoot when walking, while still keeping the ankle in a good 90deg position.
Some companies have added inflatable air pockets to the inside of their liners in order to give more customized support and offload the leg more while walking. Some conditions, like a diabetic foot ulcer or Charcot foot, might also require specific customized offloading of an area on the plantar surface of the foot. For these conditions moonboots are available with specialized air pockets and customizable insoles that can facilitate the necessary offloading.
Different categories
Low top/short moonboots: These are best suited for fractures or ligament sprains in the mid- and forefoot where the ankle joint has not been compromised. Because these boots only extend about a third of the way up the leg, it does not immobilize the ankle joint adequately enough to be the first choice as a treatment option for injuries involving the ankle joint too.
High top/tall moonboots: By far the most popular treatment option when managing fractures and ligament injuries of the lower leg, as well as Achilles tendon injuries. In the case of a surgical repair to an Achilles tendon rupture, a special wedge that is inserted inside the moonboot according to your surgeon's post operative protocol. This wedge keeps the ankle at an increased plantarflexion, and every week or 2 the wedge is reduced in order drop the heel deeper and stretch the Achilles a little bit more, until it can be removed, and the ankle can reach 90deg again comfortably.
Diabetic moonboots: Specially designed with inflatable air pockets and specialized insoles, these moonboots provide full contact support to the leg, promoting circulation whilst offloading the foot in order for a diabetic foot ulcer to have a chance to heal.
Advantages:
Easy to put on and take off
Adjustable to accommodate swelling and loss of volume
Designed to bear weight
Take off for showering, wound inspection and dressing
Disadvantages:
Rocker bottom sole makes the leg ‘longer’ and can result in back pain with prolonged use, without an even up shoe
Non-compliant patients can prolong their recovery by removing the boot too soon
Patients with very big calves and small feet struggle to get a good fit in the high top designs
Sorry to say, but with so many injuries covered by a simple moonboot, you or your family are bound to end up needing one at some point! But until then, keep on dreaming of going to the moon but keep your feet planted firmly on the ground!
