What is midfoot arthritis?
The midfoot is the central part of the foot between the hindfoot and forefoot. It consists of multiple small joints, including the important Lisfranc joint, and forms the arch of the foot. Midfoot arthritis or inflammation of the midfoot joints can occur secondary to gradual degenerative wear of the cartilage (osteoarthritis), as a complication of previous trauma such as from a Lisfranc injury, or as a result of an inflammatory condition such as rheumatoid arthritis. The natural history of this condition is usually progression over time, but can be asymptomatic.
What are the symptoms of midfoot arthritis?
Patients with midfoot arthritis generally report pain on the top of the central part of their foot which is activity-related, but can be present at rest or be unpredictable in onset. There is often swelling of the foot as well. There may also be an associated flatfoot deformity.
How can midfoot arthritis be managed?
Non-operative management strategies for midfoot arthritis include wearing cushioned stiff-sole shoes with medial arch support, using a medial arch support orthotic, losing and maintaining a healthy weight, activity modification by avoiding activities which aggravate your symptoms and by preferencing low impact-loading activities for exercise/recreation in the long term, such as swimming, cycling and Pilates, simple over-the-counter oral analgesia and/or oral/topical anti-inflammatory medication if not contraindicated as required, and/or image-guided intra-articular corticosteroid and local anaesthetic injections to the affected joints. The aim of a steroid injection is to try neutralise any chronic inflammation and provide pain relief however, this may be temporary only or can be durable in effect. Patients may similarly benefit from physical therapy or prehabilitation focusing on ankle and foot range of motion and stretching exercises, and general conditioning and strengthening of their lower limbs to optimise their pre-operative baseline, including exercising in the swimming pool or doing hydrotherapy.
What is the surgical treatment for midfoot arthritis?
Surgical treatment of midfoot arthritis relies on performing an arthrodesis or fusing the symptomatic painful joints. Fusing a major joint, such as in the midfoot, involves excising the arthritic joint surfaces, grafting the fusion site with a combination of your own bone known as autograft (and usually borrowed from your heel, ankle, knee or hip area) and allograft (processed bone from another human)/synthetic bone graft, then fixing the bones together with plates, screws and/or staples.
What is the recovery after a midfoot fusion?
After your midfoot arthrodesis, you will be non-weight-bearing through your operated foot for 8 weeks, and can then gradually progress from partial to full weight-bearing over another 8 weeks. You will be immobilised in a below-knee plaster backslab/fibreglass cast for 8 weeks, and can then transition to a CAM boot with a medial arch support orthotic. You will need to wear your CAM boot when ambulating only for this subsequent 8 weeks. It can take 3-4 weeks for your wounds to heal, 6-7 months for your midfoot fusion to unite, 7-8 months before you feel reasonably comfortable walking in cushioned sole normal shoes with medial arch support orthotics, and at least 12 months for the swelling in your foot to subside and for full recovery to your new baseline level.
What restrictions will I have after fusion of my midfoot?
Once your midfoot arthrodesis has united, there should be resolution of the arthritic pain in your midfoot since there is no longer a joint to become inflamed. Fusion of part of the midfoot is usually well tolerated and not functionally noticeable, as the midfoot joints normally have limited motion. The metalware used to fuse your midfoot does not need to be removed unless it causes a problem, such as irritation from prominence.