Abstract
Freiberg disease is an often missed clinical diagnosis. The disease may be identified as a result of the characteristic radiographic findings of collapse of the second and, less commonly, third metatarsal head or heads. Like the scaphoid, the second metatarsal joint is extremely susceptible to this disease because of the tenuous blood supply of the articular cartilage. This blood supply is easily disrupted, and this often leaves the proximal portion of the bone without nutrition, which leads to osteonecrosis. Although Freiberg disease can occur at any age, it is a disease of adolescence through the second decade. Freiberg disease is five times more common in female patients.
Keywrods
Freiberg disease, foot pain, metatarsal heads, avascular necrosis, vasculitis, HIV, radiography, ultrasound guided injection, diagnostic ultrasound
ICD-10 CODE M72.90
The Clinical Syndrome
Freiberg disease is an often missed clinical diagnosis. The disease may be identified as a result of the characteristic radiographic findings of collapse of the second and, less commonly, third metatarsal head or heads. Like the scaphoid, the second metatarsal joint is extremely susceptible to this disease because of the tenuous blood supply of the articular cartilage. This blood supply is easily disrupted, and this often leaves the proximal portion of the bone without nutrition, which leads to osteonecrosis. Although Freiberg disease can occur at any age, it is a disease of adolescence through the second decade. Freiberg disease is five times more common in female patients.
Although the exact cause of Freiberg disease remains elusive, many investigators believe that this condition is the result of repetitive microtrauma to the second and third metatarsal heads. Investigators believe that the relative immobility of the second and third metatarsals, combined with the extreme load transmission, makes these bones particularly susceptible to the development of avascular necrosis ( Fig. 132.1 ). High heels, which increase the load on the metatarsal heads, may raise the risk of the development of Freiberg disease, as well as of any disease that impairs the blood supply to the foot (e.g., diabetes, vasculitis, and human immunodeficiency virus infection). Steroids have also be implicated as a cause of Freiburg disease.
The patient with Freiberg disease complains of pain over the affected metatarsal head or heads that may radiate into the adjacent toes. The pain is deep and aching, and the patient often complains of increased pain on weight bearing and a limp when walking. The patient may or may not have a clear history of foot trauma that can be identified as the inciting incident for the disease.
Signs and Symptoms
Physical examination of patients suffering from Freiberg disease reveals pain on deep palpation of the affected metatarsal joints. The pain can worsen by passive and active range of motion. Subtle swelling over the affected joint or joints may be appreciated on careful physical examination ( Fig. 132.2 ). An antalgic gait is invariably present.
Testing
Plain radiographs are indicated in all patients who present with Freiberg disease, to confirm the diagnosis, as well as to rule out underlying occult bony disease ( Fig. 132.3 ). Early subtle sclerotic changes and joint space narrowing are often attributed to degenerative arthritis. Magnetic resonance imaging (MRI) may reveal articular changes before significant changes are evident on plain radiographs ( Fig. 132.4 ). Based on the patient’s clinical presentation, additional testing, including complete blood cell count, uric acid, sedimentation rate, and antinuclear antibody testing, may also be indicated. MRI and computerized tomography of the foot are indicated in all patients suspected of suffering from Freiberg disease, as well as when other causes of joint instability, infection, or tumor are suspected, or if the plain radiographs are nondiagnostic ( Figs. 132.5 and 132.6 ). Administration of gadolinium followed by postcontrast imaging may help delineate the adequacy of blood supply; contrast enhancement of the metatarsal joint is a good prognostic sign. Electromyography is indicated if coexistent lumbar radiculopathy or lumbar plexopathy is suspected. A very gentle intraarticular injection of the affected joint with small volumes of local anesthetic provides immediate levitation of the pain and helps demonstrate that the nidus of the patient’s pain is, in fact, the metatarsal joint. Ultimately, joint replacement is required in most patients suffering from Freiberg disease.
