Neurofibromatosis 1 and 2 (NF1 and NF2)
Conditions
Brief summary
Patients with clinically confirmed neurofibromatosis type 1 (NF1) or neurofibromatosis type 2 (NF2) or a known neurofibromatosis (NF) mutation aged 5 years and above will be eligible to participate and will be recruited from the neurofibromatosis clinic. Given the need for identifying measures that can reliably and sensitively measure focal muscle weakness and allow for measuring muscle strength as a functional outcome in therapeutic clinical trials in NF, this pilot study will assess the reliability of measuring muscle strength in NF1 and NF2 using a hand-held dynamometer.
Interventions
BEHAVIORALhand-held dynamometer
Strength of one weak muscle group and of the biceps of the dominant arm will be measured using a hand-held dynamometer. An average of three readings will be used as one observation. Three observations per patient will be obtained on one day with a minimum of 15 minute rest period between each observation.
Sponsors
NYU Langone Health
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
5 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* For cohort 1: * Patients must have clinically confirmed NF1 using the NIH consensus criteria or a known NF1 mutation * Ages 5 years and above * \< 5/5 strength on Manual Muscle Testing (MMT) testing in at least one muscle group tested on the day of enrollment * Able to follow instructions and cooperate with exam to assess strength * For Cohort 2 * Patients must have clinically (NIH or Manchester criteria) or genetically confirmed diagnosis of NF2 * Ages 5 years and above * \< 5/5 strength on MMT testing in at least one muscle group tested on the day of enrollment * Able to follow instructions and cooperate with exam to assess strength
Exclusion criteria
* No orthopedic procedure or other major surgery that could influence extremity strength in past 6 months * No tibial dysplasia
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Intra-class correlation coefficient of strength measurement in the clinically identified weak muscle | 1 day | A sample size of 20 subjects with three observations per subject achieves 90% power to detect an intraclass correlation of 0.91 under the alternative hypothesis when the intraclass correlation under the null hypothesis is 0.75 using an F-test with a significance level of 0.05. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Intra-class correlation coefficient of strength measurement in the dominant biceps | 1 day | A sample size of 20 subjects with three observations per subject achieves 90% power to detect an intraclass correlation of 0.91 under the alternative hypothesis when the intraclass correlation under the null hypothesis is 0.75 using an F-test with a significance level of 0.05. |
| standard error of measurement of measuring strength in the weak muscles | 1 day | — |
| standard error of measurement of measuring strength in the dominant biceps muscle | 1 day | — |
Countries
United States
Outcome results
None listed