Immobilisation is less frequently used as a treatment for plantar heel pain, possibly because it is less practical to completely immobilise the foot. Instead, imobilisation is reserved for use in recalcitrant (nonresponsive) cases that have failed to respond to conventional treatments. The benefit of immobilisation is that it eliminates ground reaction forces placed on the heel during weightbearing such as when standing and walking, which is when more patients notice their symptoms. By offloading the heel, you are less likely to cause irritation and this can allow the tissues to desensitise and heal.
Immobilisation can be achieved with a removable walker boot as demonstrated in the picture above or by casting. A removable boot allows the person to remove it during non-weightbearing activities such as sleeping in bed at night, however in order for the removable boot to effectively offload the painful heel, patients need to be disciplined by wearing the boot whenever weightbearing excluding short term activities such as when showering and driving for practical and safety reasons. Cast immobilisation means that you cannot remove the cast and whilst this will allow for more effective and continuous offloading, it is less practical and cumbersome than a removable walker boot.
I rarely use Immobilisation to treat plantar heel pain, however for the right patient this is an excellent treatment option, particularly if they have very severe pain levels and are really struggling to weightbear. I also immobilise the foot if patients have bone marrow oedema (bone stress injury) in addition to plantar fasciitis confirmed on MRI scan. In my experience bone marrow oedema can be difficult to settle but offloading stress on the heel bone with immobilisation helps this significantly and often gives patients instant pain relief during weightbearing and is therefore a great option for temporary pain management. Following 4-6 weeks of immobilisation to allow healing this should be followed up with a careful rehabilitation programme to regain mobility, strength and normal function of the foot and lower limb as well as starting other recognised treatment options for plantar fascitiis. If this is not done properly, it is likely the pain will recur within a relatively short period of time.