Comparison of Range-of-Motion Restriction and Craniofacial Tissue Interface Pressure in Two Adjustable and Two Standard Cervical Collars

Background: Cervical collars are designed to limit motion to prevent spinal cord injury and have been associated with pressure ulcer development.  Newly designed adjustable collars offer the potential advantages over standard collars of individualized patient fit and decreased institutional inventory.  This study compared the restrictiveness and tissue interface pressure (TIP) in four commercially available cervical collars (two standard and two adjustable).

Methods: Experimental, repeated-measures design with stratified sample based on BMI and gender.  48 (24M/24F) healthy adult volunteers were fit with four collars (two standard and two adjustable) by an RN and a Certified Ortotist in random order. Data collection included assessment of cervical range-of-motion (CROM) restrictiveness by a Physical Therapist (PT), and measurement of TIP on the mandible and occiput by a PT, in both the upright and supine positions.

Results: All collars restricted CROM as compared to no collar (p<0.0035). One standard collar was more restrictive in four movement planes (p≤0.004) than two collars, but not significantly different from one adjustable collar. One standard collar was associated with significantly lower peak TIPs on all sites and in all positions as compared to the other standard and both adjustable collars (p≤0.01). Increased peak TIPs correlated with the high BMI category across all collar types but was significantly lower in the one brand than the other.

Conclusions: All collars significantly restrict CROM as compared to no collar. Although the collar-to-collar CROM comparisons reached statistical significance, the differences may have little clinical significance. A standard collar demonstrated the lowest overall TIP in both sites and positions. Ongoing effort needs to be devoted to staff education in proper sizing and fit, particularly high BMI patients.