Bone Protective Therapy in Duchenne MD

Location: Hoofddorp, The Netherlands

Title: The 236th ENMC International Workshop on: "Bone protective therapy in DMD"

Date: 1-3 June 2018

Organisers: Dr R. Quinlivan (United Kingdom), Prof. V. Straub (United Kingdom), Prof. L. Ward (Canada), Dr J. Wong (United Kingdom)

Translations of this report:

Dutch translation by Dr E. Niks
Italian translation by Dr F. Broggi
Arabic translation by Dr. F. Aljuraibah
Greek translation by A. Kyriakou

Participants: Dr J. Adachi (Canada), Prof. F. Ahmed (United Kingdom), Dr M. Anderton (United Kingdom), Dr F. Broggi (Italy), Dr N. Crabtree (United Kingdom), Ms. P. Furlong (U.S.A.), Dr I. de Groot (The Netherlands), Dr M. Guglieri (United Kingdom), Mr. F. van Ieperen (The Netherlands), Dr S. Joseph (United Kingdom), Dr R. Keen (United Kingdom), Prof. A.  Klein (Switzerland), Mr. J. Kuijer (The Netherlands), Prof. Z. Mughal (United Kingdom), Dr E. Niks (The Netherlands), Dr S. Novotny (U.S.A.), Dr R. Quinlivan (United Kingdom), Dr S. Roberts (United Kingdom), Prof. L. Sävendahl (Sweden), Prof. U. Schara (Germany), Prof. V. Straub (United Kingdom), Mrs. A. Stringer (United Kingdom), Drs E. Vroom (The Netherlands), Dr L. Ward (Canada), Dr D. Weber (U.S.A.), Dr J. Wong (United Kingdom) and Dr M. Zacharin (Australia)

Muscle and bone strength are closely related, the ‘mechanostat theory’ describes how muscle strength, which normally increases throughout childhood, promotes bone development. In Duchenne muscular dystrophy (DMD) muscle weakness, corticosteroid treatment and delayed puberty lead to an increased risk of bone fractures (limb and vertebral). Fractures have serious consequences including pain, loss of ambulation and fat embolus syndrome. Bone health, to assess risk of fractures can be assessed by different imaging methods.

Bone protective therapy involves prevention of fractures, detection of vertebral fractures, which can be asymptomatic, treatment of fractures to reduce pain and enable ‘reshaping’ of fractured vertebrae during childhood. Most boys with DMD have delayed puberty management of this is important for bone health. It was felt that oral bisphosphonates, a class of drugs that prevent the loss of bone density, are not as effective as intravenously administered bisphosphonates, furthermore compliance with oral treatment is poor. Intravenous bisphosphonates reduce pain and promote vertebral fracture healing but there is a risk of important side effects, usually with first dose. Newer bone drugs are increasingly available and could be studied in DMD.

Clinician and patient education on bone health is essential to advance the field of bone health in DMD. Combining data that may already exist could help to answer questions about bone health. A small placebo controlled trial for prevention of first fractures is necessary together with trials comparing bisphosphonates with new treatments to treat fractures ultimately optimize care of patients with DMD. Future steps include dissemination of knowledge across all stakeholders, establishing a working group and exploring funding possibilities.

A full report is published in Neuromuscular Disorders (pdf).