Freiberg’s Disease, a form of osteonecrosis primarily affecting the metatarsal head, is most commonly found in adolescents and young adults, particularly among females. The condition results in pain, flattening, and collapse of the metatarsal head, often leading to arthritis in the metatarsophalangeal (MTP) joint over time. While its precise cause remains debated, it is generally understood to arise from a combination of factors, including trauma, abnormal foot biomechanics, and poor blood supply (ischemia) to the affected area. The disease most often affects the second metatarsal, though it can involve other metatarsals, with the third metatarsal being the next most commonly affected. This condition is sometimes mistaken for other foot ailments due to its overlapping symptoms, but careful assessment can aid in diagnosis and appropriate treatment.
Symptoms and Presentation
Freiberg’s disease typically presents with pain localized to the metatarsal head, often described as a feeling of walking on a hard object, such as a stone. This pain is most noticeable during walking, especially without proper footwear. Early-stage symptoms are often subtle but may escalate if left untreated. On physical examination, the affected toe may appear swollen, with varying degrees of fullness or deformity around the MTP joint. In more advanced stages, malalignment may develop, leading to conditions like hammer toes or crossover deformities. The range of motion across the MTP joint may also be reduced, and crepitation may be palpable during movement .
Diagnosis and Imaging
Diagnosing Freiberg’s disease requires a combination of clinical evaluation and imaging techniques. Early stages of the disease may show subtle changes on weight-bearing radiographs, such as joint space widening or increased bone density within the subchondral bone. More advanced stages reveal flattening of the metatarsal head, bone rarefaction, and possibly the formation of loose bodies within the joint. Specialized imaging, such as magnetic resonance imaging (MRI), can offer more detailed views, revealing changes in marrow intensity and flattening of the metatarsal head. Bone scans may also show a photopenic area surrounded by hyperactivity indicative of early avascular necrosis.
Staging and Classification
Freiberg’s disease progresses through several stages, each with distinct characteristics. The Smillie classification is widely used for staging the disease:
- Stage I: A narrow fissure fracture develops in the ischemic epiphysis with surrounding sclerosis in the cancellous bone.
- Stage II: Absorption of cancellous bone within the metatarsal head occurs, causing collapse of the overlying subchondral bone.
- Stage III: Further collapse and sinking of the articular surface, leaving projections on either side.
- Stage IV: Severe joint destruction with peripheral projections, making restoration of the joint surface impossible.
- Stage V: Advanced degenerative changes, including flattening and deformity of the metatarsal head, with significant joint damage .
Treatment Approaches
Treatment of Freiberg’s disease can be divided into nonoperative and surgical options, depending on the stage and severity of the disease.
Nonoperative Management
In the early stages of Freiberg’s disease (Stages I and II), nonoperative treatments are typically effective. These treatments aim to alleviate pain and prevent further damage to the metatarsal head. Common strategies include activity modification, pain medications, orthotic devices, and shoe modifications. Non-weight-bearing footwear with stiff soles or rocker-bottom shoes can help reduce pressure on the affected metatarsal. In some cases, orthotics with metatarsal bars are used to offload the painful area. These nonoperative methods are reported to be successful in 60% of cases .
Surgical Management
If nonoperative measures fail, surgical intervention may be necessary, particularly in more advanced stages (Stages III and IV). Several surgical techniques are available, each aimed at different stages of the disease.
- Core Decompression: In early stages, core decompression may be performed to relieve pressure within the metatarsal head and promote revascularization. This procedure has shown promising results in providing pain relief without causing structural changes .
- Joint Debridement: Joint debridement involves the removal of loose bodies, osteophytes, and damaged cartilage. It can be performed at various stages and has been successful in restoring function and alleviating symptoms.
- Osteotomy: In more advanced cases, metatarsal osteotomies, including dorsiflexion osteotomy or shortening osteotomy, are used to alleviate pressure on the affected joint. These procedures aim to correct deformities and improve alignment.
- Osteochondral Grafting: For severe cases where the joint surface is damaged, osteochondral autograft transplantation may be used to restore cartilage and improve joint function .
- Arthroplasty: In end-stage disease, when joint function is severely compromised, interpositional arthroplasty or joint replacement may be considered. These procedures involve the replacement of the damaged joint with an artificial implant.
Prognosis
The prognosis of Freiberg’s disease varies depending on the stage at which it is diagnosed and the treatment approach used. Early-stage disease treated with nonoperative methods typically results in good outcomes with minimal long-term disability. However, in advanced stages, surgical intervention is often necessary, and while procedures like osteotomy and arthroplasty can relieve pain and restore function, complications such as transfer metatarsalgia and joint stiffness may arise. Early detection and appropriate management are key to preventing irreversible joint damage and improving long-term outcomes.
Conclusion
Freiberg’s disease, while rare, presents a significant challenge to both patients and healthcare providers. Its multifactorial nature, involving trauma, vascular insufficiency, and biomechanical stress, requires a nuanced approach to diagnosis and treatment. By following established staging systems and utilizing a range of nonoperative and surgical options, patients can achieve improved outcomes and preserve function, particularly when the condition is addressed in its early stages.
