Aim: Since cervical joint position error (JPE) and visual dependency (VD) may reflect altered ascending inputs from the neck receptors, the aim of the present study was to test how these parameters may be impacted by those clinical parameters in cervicogenic dizziness (CGD) patients when compared with healthy subjects participants.
Materials and methods: 93 subjects participants fulfilling inclusion criteria for CGD and 98 age- and gender-matched healthy subjects volunteers - undergoing cervical relocation and rod and disc test to evaluate JPE and VD, respectively - were compared to each other. Cervical range of motion (CROM), Dizziness Handicap Inventory (DHI), Neck Disability Index (NDI), Neck pain intensity (NPI), Tampa Scale for Kinesiophobia (TSK-17) and Hospital Anxiety and Depression Scale (HADS) were also collected in both groups.
Results: When compared to healthy participants, CGD patients were found to have a higher degree of JPE in right (p = 0.008, mean difference, MD: 2.88) and left (p = 0.006, MD: 2.55) rotation as well as in extension (p = 0.011, MD: 2.31), flexion (p = 0.009, MD: 2.35) and mean value (p = 0.001, MD: 2.53) and higher degrees of error in CCW at +40° and -40° (p = 0.012, MD: 0.85 and p = 0.016, MD: 0.82, respectively) and CW at +40° and -40° (p = 0.018, MD: 0.83 and p = 0.015 MD: 0.81, respectively). CGD patients also demonstrated a significant reduction in degrees of CROM in active flexion (p = 0.011, MD: -34.63), extension (p = 0.018, MD: -21.67), left (p = 0.012, MD: -28.29) and right (p = 0.009, MD: -28.52) rotation, and left (p = 0.02, MD: -7.29) and right (p = 0.021, MD: -5.05) lateral flexion. Furthermore, these patients demonstrated higher scores in total DHI (p = 0.007, MD: 25.17) (and relative DHI-P, DHI-F, DHI-E; p = 0.009, MD: 11.4; p = 0.014, MD: 8.73 and p = 0.018, MD: 5.03, respectively), in TSK-17 (p = 0.017, MD: 17.56), and HADS, both in anxiety (p = 0.022, MD: 4.62) and depression (p = 0.02, MD: 7.31) subscale.
Conclusions: A possible common physiopathological background may impact on processes involved in both the JPE and VD behaviour, entangled in a vicious circle with the impaired subjective clinical and quality of life perception.
Keywords: Joint position error; cervicogenic dizziness; visual dependency.