BACKGROUND: Facioscapulohumeral muscular dystrophy (FSHD) presents with 2 genetically distinct types. We describe for the first time the MRI patterns of leg muscle involvement in type 2 and compare it with type 1. METHODS: The intramuscular fat content was assessed on lower extremity axial T1-weighted MRI scans in 6 FSHD1 and 5 FSHD2 patients. RESULTS: Overall, the muscle involvement profile did not differ substantially between FSHD1 and FSHD2. In the thigh, the dorsomedial compartment including the semimembranosus, semitendinosus and adductor magnus was the most affected. The quadriceps was mostly spared, but isolated involvement of the rectus femoris was common. Fat infiltration in the distal soleus and the medial gastrocnemius with sparing of the lateral gastrocnemius was a common finding; involvement of the tibialis anterior was less frequent. A proximal-to-distal increase in fat content was frequently present in some muscles. CONCLUSION: Muscle involvement appears to be independent of type, confirming a similar pathophysiological pathway in FSHD1 and FSHD2.
BACKGROUND: Facioscapulohumeral muscular dystrophy (FSHD) presents with 2 genetically distinct types. We describe for the first time the MRI patterns of leg muscle involvement in type 2 and compare it with type 1. METHODS: The intramuscular fat content was assessed on lower extremity axial T1-weighted MRI scans in 6 FSHD1 and 5 FSHD2 patients. RESULTS: Overall, the muscle involvement profile did not differ substantially between FSHD1 and FSHD2. In the thigh, the dorsomedial compartment including the semimembranosus, semitendinosus and adductor magnus was the most affected. The quadriceps was mostly spared, but isolated involvement of the rectus femoris was common. Fat infiltration in the distal soleus and the medial gastrocnemius with sparing of the lateral gastrocnemius was a common finding; involvement of the tibialis anterior was less frequent. A proximal-to-distal increase in fat content was frequently present in some muscles. CONCLUSION: Muscle involvement appears to be independent of type, confirming a similar pathophysiological pathway in FSHD1 and FSHD2.
Authors: Teresa Gerhalter; Benjamin Marty; Lena V Gast; Katharina Porzelt; Rafael Heiss; Michael Uder; Stefan Schwab; Pierre G Carlier; Armin M Nagel; Matthias Türk Journal: J Neurol Date: 2020-10-12 Impact factor: 4.849