ARTHRITIS OF THE HINDFOOT
What is it?
Degenerative changes in the joints at the back of the foot, usually resulting from trauma to the area (fractures, dislocations or sprains), from other deformities (such as flat feet) or from inflammatory causes. The cartilage lining the joint surfaces becomes damaged and results in pain and stiffness. The joints involved are the subtalar, talonavicular and calcaneocuboid joints.
Symptoms
Patients typically have pain on the top of the foot often mistaken as ankle pain as well as on the lateral side of the back of the foot. This pain can be worse in the morning and progresses with prolonged weightbearing. There is associated swelling and with time more obvious deformities in the foot can develop.
Non-operative management
Initial pain relief can be achieved with analgesics, anti-inflammatory medications, modification of footwear and activities, as well as orthotics to off-load the painful area. Depending on the patient, weight loss may help reduce the pressure in this area, as well as physiotherapy to keep the joints supple and surrounding
muscles strong.
If these measures fail to resolve symptoms, a corticosteroid injection into the joint may be of benefit to help control pain and allow activities to continue.
Surgical management
This depends on the stage of the arthritic process. If the arthritis is mild-to-moderate, with the pain resulting from the pressure effect of bone spurs present it is reasonable to remove these to help with these symptoms.
However, if there is rigid movements and the arthritis is more advanced, the operative option is to fuse the joints affected to alleviate the pain. This may involve one or more of the joints of the hindfoot. If all three joints are to be fused this is called a triple fusion. The incision for the talonavicular joint is on the top of the foot, and a lateral foot incision is utilised for the subtalar and calcaneocuboid joints. With this procedure the joint surfaces are prepared, by removing any remaining cartilage tissue and hard (sclerotic bone) and joining the bones on either side of the joint together. This is usually held with either screws, staples or a
combination of both. Once healed the joint remains stiff and therefore the pain resolves as the joint surfaces can no longer rub on each other.
Complications
As with any surgery there are potential risks. This will be discussed in more detail during the consultation, however common complications are stiffness, swelling, nerve injury, infection, non-union, under correction and over correction of positions and prothesis loosening.
Recovery
If a bone spur removal is performed, your foot will be in bandaging and a surgical shoe will be provided to allow you to weight-bear whilst protecting the foot. You will be provided with crutches for support. Elevation, as much as possible, is important in the first few weeks. The bandaging will come down at 2 weeks and dressings changed. You can go back to wearing comfortable shoes at this stage. Return to work can be considered at this stage if the wound is fully healed.
If a fusion procedure has been performed your leg will be placed in a below-knee cast for 2 weeks, at which stage a wound check will be performed and a complete below-knee cast applied for a further 4 weeks. For this initial 6 weeks no weight-bearing will be allowed, and crutches will be supplied for support. Elevation, above the heart level, as much as possible, is important. After 6 weeks a walking boot will be applied, and weight-bearing will be permitted in the boot for 6 weeks and physiotherapy instigated.
Swelling can be expected to be present for up to 6 months, particularly in the evenings.
With regards to return to work, it is dependent on the amount of weightbearing required. If the work is sedentary and you can keep the foot elevated, then return after 6 weeks is satisfactory. Otherwise, return to work should be expected after 10-12 weeks.