You are in: eMedicine Specialties > Orthopedic Surgery > FOOT AND ANKLE Köhler DiseaseArticle Last Updated: Sep 18, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 11
  Author: Bernardo Vargas-Barreto, MD, Consulting Staff, Department of Orthopedic Surgery, Centre Hospitalier Universitaire de Lausanne, Suisse Coauthor(s): Mark Clayer, MD, MBBS, FRACS, FAOrthA, Head of Musculoskeletal Tumor Service, Queen Elizabeth Hospital; Senior Visiting Medical Specialist, Department of Orthopaedics and Trauma, Royal Adelaide Hospital and Women's and Children's Hospital Editors: Heidi M Stephens, MD, Associate Professor, Department of Surgery, Division of Orthopedic Surgery, Director of Diabetic Foot Clinic, Assistant Dean for Clinical Outreach, University of South Florida College of Medicine; Courtesy Joint Associate Professor, Department of Environmental and Occupational Health, University of South Florida College of Public Health; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Shepard R Hurwitz, MD, Director of Clinical Services, Department of Orthopedic Surgery, University of Virginia School of Medicine; Director, Division of Foot and Ankle Surgery, Department of Orthopedic Surgery, University of Virginia Health System; Dinesh Patel, MD, FACS, Associate Clinical Professor of Orthopedic Surgery, Harvard Medical School; Chief of Arthroscopic Surgery, Department of Orthopedic Surgery, Massachusetts General Hospital; Jason H Calhoun, MD, FAAOS, Chairman, J Vernon Luck Distinguished Professor, Department of Orthopedic Surgery, University of Missouri Author and Editor Disclosure Synonyms and related keywords: avascular necrosis of tarsal navicula, osteochondritis of tarsal navicula, Kohler disease, Kohler's disease, Köhler's disease, osteochondroses, osteonecrosis of the foot, foot osteonecrosis INTRODUCTIONSection 2 of 11
  In 1908, Köhler first described the disease named in his honor (the name of the first author who describes the bone abnormalities often becomes the accepted eponym).1 This clinical entity belongs to a group of conditions called osteochondroses, which have been reported since 1903. Approximately 40 different osteochondroses are reported in the literature. In these self-limited diseases, there is avascular necrosis of primary or secondary centers of ossification; almost all of the epiphyses, apophyses, and small bones can be implicated. The etiology of these conditions is not well known, but vascular accidents, coagulation anomalies, and heredity have been implicated. The most common osteochondroses are Legg-Perthes-Calve, Osgood-Schlatter, Sinding-Larsen-Johansson, Kienbock, Freiberg, and Panner diseases. ProblemAvascular necrosis of the navicular bone occurs. FrequencyKöhler disease is rare. To the authors' knowledge, no accurate prevalence figures are available. This disorder can begin very early, after age 2 years, but it is more frequent in children aged 5-10 years. Köhler disease is far more common in boys than in girls; however, girls with this condition are often younger than are boys with the disease. This is probably due to the onset of ossification in girls, which occurs at age 18-24 months, whereas in boys, ossification occurs at age 24-30 months. EtiologyAs with the other osteochondroses, the etiology of Köhler disease is unknown. Nevertheless, a vascular incident and a retarded bone age have been implicated. PathophysiologyVascularization of the navicula occurs in 2 ways and is identical in adults and children. A branch from the dorsalis pedis artery crosses the dorsal surface of the navicula and gives off 3-5 branches. Some small branches come from the medial plantar artery to supply the plantar surface. These blood vessels create a dense network around the bone and come from the perichondrium toward the center of the cartilage. Less commonly, a single dorsal or plantar artery is found in anatomic specimens. Köhler suggested that the changes in this disease might be the result of an abnormal strain that acts on a weak navicula, but a definitive answer has not been found. Among the theories to explain the nature of this lesion, a more satisfactory one is a mechanical basis that is associated with a delayed ossification. The navicula is the last tarsal bone to ossify in children. This bone might be compressed between the already ossified talus and the cuneiforms when the child becomes heavier. Compression involves the vessels in central spongy bone, leading to ischemia, which then causes clinical symptoms. Thereafter, the perichondral ring of vessels sends the blood supply, allowing rapid revascularization and formation of new bone. The radial arrangement of the vessels of this bone is of great importance in explaining why the prognosis of this lesion is always excellent. ClinicalIn this uncommon condition, children present with an antalgic limp and local tenderness of the medial aspect of the foot over the navicula. The child can walk with an increased weight on the lateral side of the foot. Frequently, there is swelling and redness of the soft tissues. INDICATIONSSection 3 of 11
Surgery is not indicated for Köhler disease. Clinical management is discussed in Treatment, Medical therapy. RELEVANT ANATOMYSection 4 of 11
See Pathophysiology. CONTRAINDICATIONSSection 5 of 11
Surgery is not indicated for Köhler disease. WORKUPSection 6 of 11
Imaging Studies
TREATMENTSection 7 of 11
Medical therapyA weight-bearing, below-the-knee cast is recommended. Total cast time is approximately 6-8 weeks. The cast is better in moderate varus (10-15º) that is associated with moderate equinus (10-20º). In this position, the navicula is relaxed from posterior tibialis strain. Arch supports can be prescribed following the cast period and used for an average of 6 months. In mild cases, soft arch supports may be the only treatment necessary. Follow-upSymptoms in treated patients can last for less than 3 months.3 In untreated patients, symptoms may be present for 15 months. As immobilization in a short leg cast decreases the duration of symptoms, treating all patients for at least 6 weeks is recommended. If pain is persistent after a 6-week period of casting, a new cast must be applied for 6 supplementary weeks. Other causes of foot pain, including talar coalition or an accessory navicular, should be investigated if the pain does not disappear after the cast period. COMPLICATIONSSection 8 of 11
In 1984, Ertel and O'Connell reported a case of acquired talonavicular coalition that followed avascular necrosis of the tarsal navicular bone.4 This complication is very rare. OUTCOME AND PROGNOSISSection 9 of 11
The evolution of the x-ray appearance in Köhler disease is variable. Normal x-rays may be obtained 6-18 months following onset. At adulthood, the navicular bone is expected to be normal. Patients recover excellent function.5 MULTIMEDIASection 10 of 11
REFERENCESSection 11 of 11
Article Last Updated: Sep 18, 2007 | |||||||||||||||||||
