Table 1 Reviewed articles for tissue interface pressure

Jacobsen et al., 2008 [5]

USA

Literature review

Reduction in occipital pressure ulcers

Improved nursing education and a variety of collars caused an reduction in occipital ulcer incidence

Only looked at their own trauma centre

Liew et al., 1994 [13]

Australia

Case review: 2 patients

Pressure ulcer development

Ulceration is a complication of hard collar use

Only looked at 2 patients

Murphy et al., 1997 [14]

USA

Case review: 1 patient

Pressure ulcer development

Occipital pressure ulcers after collar use are common; improved wound care/more suitable collars advised

Only one patient reviewed

Walker, 2012 [4]

UK

Retrospective analysis:

Pressure ulcer development

Cervically immobilised patients have an increased risk of developing pressure ulcers

Looked at all types of immobilisation not just semi-rigid collars

90 patients

Powers, 1997 [20]

USA

Retrospective analysis

Pressure ulcer development

Improved education, more suitable collars plus early collar removal protocol resulted in a ulcer reduction

Only looked at their own trauma centre

Blaylock, 1996 [19]

USA

Retrospective analysis and study: 20 patients

Pressure ulcer development

Improved education on skin condition/wound care and collar fitting, plus a new collar design resulted in no ulcers in the subjects.

Possibility that the team were conscious regarding ulcer development. Small sample size and only one trauma centre included

Molano et al., 2004 [15]

Spain

Retrospective study:

Pressure ulcer development

23.9% had ulcers; with occipital ulcers being more problematic to treat

Only looked at their own unit

92 patients

Chendrasekhar et al., 1998 [21]

USA

Retrospective study:

Pressure ulcer development

Ulceration is related to duration of collar wear; early collar removal advocated

Only 34 patients actually included due to mortality and only 8 had their collar removed earlier than normal

52 patients

Beavis, 1989 [17]

UK

Study: 10 volunteers,

Tissue Interface Pressure at chin and occiput

Passive and active results showed wide variance, but Beavis felt that the pressure was a positive feature, being an incentive not to move

No consideration for the impact of high interface pressure

4 collars

(25-172 mmHg)

Black et al., 1998 [22]

USA

Study: 20 volunteers,

Tissue Interface Pressure at occiput (39-83 mmHg) plus skin temperature and humidity

No difference between the interface pressures of the collars was found; felt skin humidity was an important factor in ulcer development

Collars were worn for up to 30 minutes possibly impacting on pressure readings due to foam compression within the collar

2 collars

Ferguson et al., 1993 [10]

UK

Study: 5 patients,

Tissue Interface Pressure around neck area (1.2-11.8 mmHg)

Pressures recorded depended on the tightness of the collar

Sensor positions were possibly not indicative of true pressure points; tensions applied were subjective

6 collars

Fisher, 1978 [16]

USA

Study: 8 patients,

Tissue Interface Pressure at chin an d occiput

Passive interface pressures varied with collar tightness:

Used the same person to apply the collar; ‘tightness’ was subjective

1 collar

(25-105 mmHg)

Plaisier et al., 1994 [18]

USA

Study: 20 volunteers,

Tissue Interface Pressure at chin, occiput and mandible (27-57 mmHg); plus comfort

Philadelphia/Stifneck collars exceed capillary closing pressure in some positions, yet Newport/Miami J did not; comfort ratings tallied with this

Skin humidity temperature data would have confirmed their ‘skin friendly’ endorsement of the Newport and Miami J collar

4 collars

Tescher et al., 2007 [23]

USA

Study: 48 patients,

Tissue Interface Pressure at occiput and mandible

Miami J/Miami J with Occian back had lower pressures recorded both seated and supine; however all maximal pressures recorded exceeded capillary closing pressure

Admit that interface pressure is an important consideration in ulcer development but admit other factors may play an important part

4 collars