Drop foot (also known as dropped foot, foot drop or floppy foot) refers to a weakening of those muscles that allow the ankle and toes to flex, causing difficulty in moving the ankle and toes upwards (dorsiflexion). This causes the individual to drag their toes while walking and to compensate by bending the knee and hip to lift the foot higher than usual, to prevent it catching on the ground during swing phase.
While drop foot is a neuromuscular disorder that affects the nerves and muscles, it is not actually a disease in itself, but rather a symptom of some other medical problem.
If drop foot is caused by an injury or nerve damage, recovery is often possible. However, if it's caused by permanent nerve damage or a progressive neurological condition, such as multiple sclerosis, it will be a lifelong symptom to manage.
The immediate risk factors involve tripping and falling. Clearly, this is to be avoided particularly in the older population that has a higher risk of further injury, such as fractures.
Medium- to long-term risks of leaving drop foot untreated are problems related to the skeletal system. They involve pain in the forefoot, collapse of the midfoot, hip and knee alignment problems and postural problems, which can cause back pain.
Complications and related diseases
Drop foot can lead to many other orthopaedic problems, if left untreated. These can include: metatarsalgia; flat foot; tightness in the calf and Achilles tendon; and hyper extension of the knee.
It will also make walking more difficult. Often patients complain of having to constantly look at the floor while walking, which is tiring. This can lead to postural problems such as a Kyphotic Posture.
Tests and Diagnosis
Assessment for drop foot requires a full biomechanical assessment. This includes: assessing joint ranges of movement; joint stability; muscle strength; standing posture and alignment; and a gait/walking assessment.
There are many different types of orthoses that can be used to treat drop foot. Some are very simple and purely deal with the drop foot. These can include some elasticated supports and the 'foot-up' device.
Some are more advanced, and will require a bespoke or made-to-measure device. These tend to involve an ankle foot orthoses (AFO), of which there are many different types depending on the exact biomechanical requirement. Different materials, such as plastic and carbon fibre offer different solutions. The basic aim of each design will be to control the foot drop during the swing phase part of the gait cycle and ensure that any initial contact with the ground occurs with heel contact. The bespoke options will also be designed to control the medial/lateral stability of the ankle, and ensure that the lower leg is prepositioned during stance phase to allow as normal a gait pattern as possible.
Also, in some cases where the cause of the rrop foot is an upper motor neurone problem, Functional Electronic Stimulation (FES) may be recommended.
Choosing the correct orthosis is essential. Although some devices appear to resolve the short-term risk factors, such as tripping, they do not prevent the longer-term risks of orthopaedic damage.
At LOC, we will make sure you understand what you orthosis will and won’t do, and ensure that you receive the most appropriate orthosis for your particular condition.