When Medial Foot Problems Have Lateral Symptoms
Lateral foot pain may be associated with problems of the lateral or medial foot. Often, if there is a problem on the medial aspect of the foot, your patient may also note that he or she has had long-term pain on the lateral aspect of the foot and ankle. Here is a common finding I see in my practice that may help you diagnose and treat lateral foot pain.
A 58-year-old female has chronic pain in the lateral aspect of her right foot. She has had the pain for six months and says it has been getting worse in the past one to two months. She recently increased her level of activity with more charity work and has had more pain in the lateral foot region as a result. Prior to this increased activity, the patient spent most of her time in her garden on her knees and had limited her activity in the past few years due to periodic arch pain.
While she notes a family history of flatfoot problems, the patient says no one in her family has had the same problems she has with ambulation. The patient says the pain only occurs with ambulation and subsides with rest. She has not found anything to help with the pain, although she notes certain shoes are more comfortable than others. She also reports periodic shooting pains on the lateral foot and has weakness of the entire foot associated with her low arches.
The patient is a healthy, slim woman with no significant medical history. She takes estrogen and vitamins only. She has had two children with regular birth and no other surgical history.
What Is The Differential Diagnosis?
1. Sinus tarsi syndrome
2. Arthritis of the midfoot or rearfoot
3. Stress fracture of the heel
4. Plantar fasciitis
5. Tendonitis/tendon tear
What The Examination Reveals
Vascular and neurologic examinations are normal. There is no loss of sensation to the foot and dermatome sensation is grossly normal. There is some shooting pain noted on the lateral aspect of the subtalar joint in the region of the sinus tarsi. This pain radiates into the medial sinus tarsi, which, upon examination, seems to be the most painful area.
There is mild edema of the lateral sinus tarsi with a slight increase in edema of the peroneal tendons in the region of the sinus tarsi. The patient has grossly normal skin color with no discoloration or ulcerations.
She does have an equinus with -5 degrees of dorsiflexion with the knee extended and 10 degrees of dorsiflexion with the knee bent. There is also weakness of the posterior tibial muscle, which is difficult to examine due to anterior tibial substitution during testing. On the lateral foot, there is mild peroneal spasm which is holding the foot in a pronated position. The peroneal tendons are painful to palpation on the lateral aspect of the posterior distal fibula. All other muscle groups are grossly intact in strength and function.
The rearfoot is slightly stiff to range of motion at the subtalar joint. The subtalar joint is not painful to range of motion and there is no crepitus. I did notice an increase in rearfoot motion with decreased peroneal spasm after the patient relaxed. She also has increased midfoot motion with increased motion of the subtalar joint. There is no pain or crepitus in the midfoot joints at the midtarsal joint.
Weight-bearing examination of the foot shows a severe heel valgus with peroneal spasm. There is an arch collapse with mild abduction of the forefoot at the midtarsal joint. The affected foot shows a greater level of valgus and arch collapse than the opposite foot. After asking the patient to do a bilateral heel raise, I noticed a very weak heel raise in which the heel remained in slight valgus without showing any varus. Single heel raise is negative with testing.
Radiographs show a medial arch collapse at the naviculo-cunieform joint with a valgus heel and subsequent decrease in calcaneal height. The radiographs also reveal an adducted talus with unroofing at the talonavicular joint, and minimal degenerative changes of the rearfoot with no signs of stress fracture or gross fracture.