What is the role of MRI in the workup of limb-girdle muscular dystrophy (LGMD)?

Updated: Aug 15, 2019
  • Author: Monica Saini, MD, MBBS, MRCP(UK); Chief Editor: Nicholas Lorenzo, MD, MHA, CPE  more...
  • Print
Answer

Magnetic resonance imaging (MRI) can help differentiate forms of LGMD. Hyperintense signal change on T1 scans is seen in more severely affected muscles. An MRI study of 20 patients with LGMD showed the following:

  • Patients with LGMD2A show prominent involvement of thigh adductors, hamstrings, and medial head of the gastrocnemius, with sparing of the sartorius. Serial imaging shows stronger deterioration in the soleus muscle, vastus intermedius, and biceps femoris. [69]

  • Patients with LGMD2B can have a variable MRI picture. The adductor magnus, quadriceps, and calf muscles are predominantly involved, with relative sparing of the Sartorius and gracilis muscles. [70] Involvement of gastrocnemius predominates in Miyoshi myopathy, and involvement of glutei and anterior and posterior thigh muscle is prominent in patients with a LGMD phenotype. Tibialis anterior and axial abnormalities are described in patients with anterior tibial myopathy and axial myopathy, respectively.

  • Patients with sarcoglycanopathies do not show any major differences regarding pattern of muscle involvement, as seen on MRI. Adductor and glutei muscles seem to be the first affected, with a proximodistal gradient evident in the vastus lateralis. Adductor longus may show some areas of sparing, with a complete or relative sparing of tibialis posterior and flexor digitorum longus. Less consistently, a relative hypertrophy of either sartorius or gracilis may be seen. [71]

  • Patients with LGMD2D and with Becker muscular dystrophy had more severe MRI changes in the anterior thigh compartment than in the posterior thigh.

  • Muscle tissue in patients with LGMD2I who have the founder mutation c.545A>G in FKRP shows a distinctive concentric pattern of fatty infiltration and edema on MRI, most pronounced in the vastus intermedius and vastus medialis muscles around the distal femoral diaphysis. [72]


Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!