This is a common question pondered over by both patients and clinicians, and it is my experience that patients have mixed results with orthotics. I often get asked if I use orthotics with my PFPS patients, and the answer quite simply is, ‘sometimes’. Below are some of the thought processes I go through when deciding if someone will benefit.
When does the person get most of their pain? There are a group of PFPS patients who primarily get their worst pain when sat with the knee flexed, (cinema sign), and struggle with activities such as driving. Even if I saw an excessively pronating foot I would pay much more attention to other factors such as muscle length, in these patients.
When I observe patients in single stance I am interested to try and establish where their ‘wobble’ is coming from. Is it in the frontal plane at the hip, eg a loss of control from gluteus medius as an abductor, or is the rearfoot swinging in and out of valgus? If the loss of control is in the horizontal plane I am looking at femoral control. I would then be looking to correlate this finding with their gait finding. A long slow deceleration of femoral rotation during gait demonstrates poor eccentric gluteus maximus control and this won’t help a foot that has a tendency to excessively pronate. What would I do? Correct the eccentric rotation control first, and then see if that is sufficient to help with distal stability.
There are some patients that despite working on their pelvic and or hip control do not respond, and I think this is for two different reasons. Firstly an excessively pronating foot encourages abnormal firing patterns around the hip, and sometimes you need an orthotic to help facilitate the proximal firing through better plantar sensory input. Secondly there are a group of patients who no matter what you do proximally will still excessively pronate, and in my experience they are often hypermobile, with a highly flexible foot.
Just to complicate matters thee are a group of patients who I would be very cautious in prescribing an orthotic for. These are people with an abnormally large TTTG distance. The increased external rotation of the tibia that can come about from an orthotic can increase instability. Furthermore, male runners with a functional genu varum have been shown to overload their medial patella facet. An orthotic may decrease the Q angle, further loading up the medial patella facet.
Finally pragmatics has to play a part. If someone is sporty and wearing trainers, there is a much better chance of them wearing an orthotic than a female who enjoys heels and dainty ballet pumps.
I invite discussion on what clearly is not a ‘black and white’ field!