The Post Concussion Symptom Scale May Exhibit A Ceiling Effect in Women with Post Concussion Syndrome: A Case Series

Abstract:

Background: Post Concussion Syndrome (PCS) is widely defined as the presentation of persistent signs and symptoms 1 month or more after a concussive event, and it is characterized as exhibiting 3 or more of the following signs or symptoms: dizziness, fatigue, irritability, poor concentration, memory limitations, headache, and insomnia. PCS can be life-altering and adversely affect independence in functional activities of daily living, work, and caregiver abilities.  PCS is reported to affect more women than men. One of the outcome tools that has shown validity in individuals with PCS is the post-concussion symptoms scale (PCSS).  PCSS is a self-reported scale and helps to establish a base of PCS for individuals in the outpatient setting.  However, limited research exists on the efficacy of the PCSS populations of adults with PCS who are non-military, non-athletes. This case series describes 7 women who were diagnosed with PCS and the integration of the PCSS within their rehabilitation in an outpatient physical therapy setting.

Case description: The PCSS was administered in the outpatient setting to 7 women patients diagnosed with PCS.  At the time of initial evaluation, each had primary complaints of unstable gait, none were able to tolerate vestibulo-oculomotor testing at initial evaluation, and all had abnormal Modified Clinical Test of Sensory Interaction on Balance (mCTSIB) testing. During physical therapy, each received detailed screening of the neurologic system, as well as individualized treatment, including canalith repositioning techniques, therapeutic exercise, and oculomotor training, and cognitive behavior therapy, as individually indicated.  

Outcomes: The initial PCSS scores for this group were suspected to have a ceiling effect, suggesting that this instrument may lack sensitivity and specificity for non-military, non-athlete samples such as the present one. Nonetheless, 6 of 7 women in this case series had improved scores on the PCSS over the course of her rehabilitation. Average improvements of 21.3 points from initial evaluation to discharge were recorded.  Each patient in this case series noted having positive gains with gait stability, ranging from self-reported 30% to 100% improvement.  Of the 3 who were not working at initial evaluation, all returned to work in a functional capacity; 2 returned fully, 1 returned with restriction due to awaiting a shoulder surgery.  

Discussion: Outcome tools for adults with PCS who are neither military nor athletes need to be further investigated. The present case series suggests the PCSS lacks sensitivity and specificity for this population, prompting questions regarding issues such as minimal detectable difference and other variables helpful in clinical screening and decisions regarding discharge to previous activity levels. Future study on the PCSS or other instruments in non-military, non-athlete adults with PCS would be valuable, helping perhaps to both establish normative data and link clinically significant change to functional improvement.  



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