Müller Weiss Disease: Our 30-year-experience

Abstract

Müller-Weiss disease (MWD) is a condition that involves a dysplastic navicular bone with asymmetric talonavicular arthritis and secondary hindfoot varus deformity. Although its prevalence is supposed to be low, it is much more common than reported as many cases are asymptomatic, undiagnosed, or misdiagnosed. Understanding aetiology and epidemiology is important to know about the background of MWD. Although it has traditionally been presented as a necrosis of the navicular, we now know it is apparently the result of mechanical disturbances occurring around the bone that ultimately cause deformity and an asymmetric arthritis of the talonavicular joint. The uneven wear and progressive thinning of the lateral part of the joint gradually shifts the talus over the calcaneus thus creating subtalar/hindfoot varus. Rotational and medializing moments acting on the dysplastic navicular cause medial protrusion and plantar collapse of the bone. It is essential to understand pathogenesis as it directly relates to diagnosis and management of this condition. Conservative treatment involves correcting subtalar varus as a deforming force around the midfoot and hindfoot. Insoles with a pronatory wedge from the heel to the metatarsal region and longitudinal arch support are usually effective in providing pain relief and improving function. Patients who fail to respond to insoles may be treated surgically. Conventional talonavicular (or extended) arthrodesis does not address the underlying pathomechanics. An isolated valgus (Dwyer-type with lateral slide) osteotomy of the os calcis has shown to be effective for most patients. After 30 years studying MWD, we will try to provide a basic understanding of the pathogenesis, pathomechanics, diagnosis, and ultimately both conservative and surgical treatment of this challenging and not so uncommon condition.