Objective To identify the presence of cervical, vestibulo-ocular, and physiological subsystem impairments in symptomatic individuals 4 to 26 weeks following concussion.

Design cohort.

Setting Tertiary teaching hospital, University.

Participants Thirty-eight participants aged 18–60 years with a diagnosis of mTBI 4 to 26 weeks post-concussion were included. Participants with a previous diagnosis of neck pain, vestibular or neurological conditions or pharmacological confounders were excluded.

Outcome Measures Presence of specific patterns of cervical spine (sensorimotor or musculoskeletal), vestibulo-ocular, or physiological subsystem dysfunction was determined by pre-defined published criteria. Percentages of participants with impairments in each subgroup were calculated. Participant results were individually analysed to investigate agreement between subsystem impairments on physical examination with clinically relevant scores on symptom specific questionnaires. Percentages of agreement were calculated for the whole group and individual subgroups.

Main Results All three subsystems were impaired in 35.29% of participants. Two subsystems were impaired in 47.06% of participants and one subsystem was impaired in 14.7%. The agreement between physical impairment measures and questionnaires for the cervical, vestibulo-ocular and physiological subsystems were 70.59%, 50% and 44.12% respectively. The highest overall agreement of 69.44% was found in the group of participants with impairments across all three subsystems.

Conclusion Findings of this study indicate that underlying impairment of two or more subsystems is common (82%) in adults reporting persistent symptoms 4 to 26 weeks post-concussion. Symptom specific questionnaires may not identify these and thus a comprehensive physical examination across all subsystems is warranted.