Development of a novel measurement tool of oral strength in FSHD

Investigators: Laura Johnstone PT MPT PhD, Leo H Wang MD PhD

Category: Research - Clinical

The most prominent symptom of FSHD is orofacial weakness. This is due to weakness in the orbicularis oris—multidirectional muscle fibers that surround the mouth—responsible for the shape and movement of the lips. Weakness of this muscle and other facial muscles affects facial expression, communication, and swallowing.1 These impairments have been identified as burdensome by patients with FSHD.2,3 Yet, we do not have yet reliable measurement tools to detect weakness and progression of weakness. We propose the investigation of a novel tool to measure the strength of the entire orbicularis oris, using the FaceFormer device adapted to the Quantitative Muscle Testing device. We will assess 30 FSHD1 and 30 control patients. We will compare the utility of the tool to self-reported facial function on the Facial Disability Index and physician assessed facial function using the Facial Function Score.


  1. Park HS, Kim JU, Park JY, Oh DH, Kim HJ. Comparison of orbicularis oris muscle strength and endurance in young and elderly adults. J Phys Ther Sci. 2018;30(12):1477-1478.
  2. Johnson NE, Quinn C, Eastwood E, Tawil R, Heatwole CR. Patient-identified disease burden in facioscapulohumeral muscular dystrophy. Muscle Nerve. 2012;46(6):951-953.
  3. Mul K, Berggren KN, Sills MY, et al. Effects of weakness of orofacial muscles on swallowing and communication in FSHD. Neurology. 2019;92(9):e957.


Original grant amount for $20,000 for a one year study.

Project was discontinue this project for the following reason:

  1. the initial findings showing that this instrumentation is not showing adequate reliability in FSHD;
  2. COVID-19 precautions/restrictions made trouble-shooting and recruitment difficult; 3) roles and responsibilities for the PI have changed and it is believed this difficult problem will require more time than initially anticipated.


Related Material

See Recruitment Flyer

See Study Summary Article

See Progress Update