The Upper Limb Hypermobility Assessment Tool: A novel validated measure of adult joint mobility

Abstract

Background: Existing measures of generalized joint hypermobility do not include commonly affected upper limb joints.

Objective: To evaluate the reliability of a novel clinically-applicable measure of upper limb joint mobility, its ability to discriminate between varying extents of hypermobility, identify generalized joint hypermobility, and to establish a cut-point for hypermobility classification.

Design: Validation of a diagnostic tool.

Method: Participants were sought from three groups - healthy controls, likely and known hypermobiles, and assessed using the Upper Limb Hypermobility Assessment Tool (ULHAT), Beighton score and clinical opinion. Pearson's correlation coefficient examined individual group and whole cohort relationships between upper limb hypermobility, age, gender and ethnicity. MANOVA investigated between-group differences in ULHAT scores. Median interquartile ranges and ROC Curve analysis identified the cut-off score for identification of upper limb hypermobility. Percent agreement with clinical opinion assessed the ability of the ULHAT to identify generalized joint hypermobility.

Results: 112 adult participants (mean age 24.3 ± 5.5years) across the three groups were assessed. Inter-rater reliability of the tool was high (ICC2,1 = 0.92). The cut-point was established at ≥7/12 (sensitivity 0.84, specificity 0.77, +LR 3.7, -LR 0.2). Upper limb hypermobility did not vary with age or ethnicity (both p > 0.12), but was greater in females (p < 0.001). The ULHAT discriminated between the three groups and identified generalized hypermobility.

Conclusions: The 12-item ULHAT measures mobility of multiple upper limb joints in all movement planes. Using a cut-off of ≥7/12 in adults, the ULHAT is a reliable and valid tool for identifying upper limb hypermobility and generalized joint hypermobility.

Keywords: Clinical assessment; Ehlers-Danlos syndrome; Generalized joint hypermobility; Measurement.