Thesis presentation-2

Philip Fess, Darcy James, John Murphy, Joe Myers, Michelle Rooney, Jason

Taylor, Lisa Torii

EFFECT OF MATTRESSES AND PILLOW DESIGNS ON

PROMOTING SLEEP QUALITY, SPINAL ALIGNMENT, AND PAIN

REDUCTION IN ADULTS: SYSTEMATIC REVIEWS OF

CONTROLLED TRIALS

Eight hours of sleep is recommended per night Average American receives 6.8 hours per night

75% of Americans report sleep difficulties Estimated 100 million individuals will report sleep difficulties by 2050

Main causes of sleep disturbances: Sleep surface Musculoskeletal pain

33% of population report neck pain 30% of population report back pain

INTRODUCTION

Jacobson, 2009; Jacobson, 2010; Rogerson, Gatchel, & Bierner, 2010

Mattress & Pillow designs

Sleep disturbances

Associated back and/or neck pain

Unsupported claims from

manufacturers

Lack of current research

Provide a systematic reviews of the literature regarding designs of pillows and mattresses in relation to: Pain Reduction Promoting sleep quality Spinal alignment

Guide health professionals in recommendations of sleep surfaces

PURPOSE

METHODOLOGY

Pillow

&

Mattress

Inclusion Criteria

DatabasesSearch

StrategyResults Data

Extraction

SEARCH STRATEGY

• Pillow/Mattress and Ergonomics

• Pillow/Mattress and Pain

• Pillow/Mattress and Spine

• Pillow/Mattress and Alignment

RESULTS AND SCREENING CRITERIA

Pillow Mattress

Results

16 Articles

6 Articles

62 Articles

24 Articles

•2 Independent Raters• 3rd Party

•Data Extraction Form

•PEDro Rating

•Summaries

PILLOW RESULTS AND DISCUSSION

6 ARTICLES

Author (year)

PEDro Study Design Category Number of Patients

Present Condition Outcome Conclusion

1. 6 Comparative, single subject study

Pain Reduction 30 Asymptomatic Pain and pillow height

Pillow should have cervical and shoulder support. Pillow height is directly positively proportional influences pillow comfort.

2. 6 Random-allocation block-design trial

Sleep quality 106 Asymptomatic Cervical Stiffness andHeadaches

Latex pillows are recommended to help control waking headache and scapular/arm pain while feather trial pillow produces the highest frequency of waking symptoms amongst the participants.

3. 6 Randomized-block design

Cervical Spine Alignment

 95 Asymptomatic Spinal alignment The feather pillow demonstrated the least amount of segmental stability at all levels.

4. 5 Random allocated block 

Pain reduction and Sleep quality

99 

Asymptomatic 

Waking Cervical pain. Pillow comfort and sleep quality  

Rubber pillows performed the best with regards to waking cervical pain, sleep quality and pillow comfort. Feather and Foam contour perform the worst with these respects. 

5. 

5 Controlled comparative

Sleep quality 7 Asymptomatic Sleep quality and skin temperature

Sleep quality improved with cooling of the occipital region.

6. 

4 cross-sectional study 

Pain reduction 106 

Asymptomatic 

Cervical pain, pillow comfort and sleep quality  

Latex pillow rated the highest while the feather pillow rated the lowest with regards to sleep quality and pillow comfort.

Spine Alignment

Pain Reduction

Sleep Quality

PAIN REDUCTION

Liu, S., Lee, Y., Liang, J. (2011)

A comparative study 30 participants

Four different pillow designs Standard, cradle, cervical, shoulder

Conclusion Pillow number four was most comfortable

SHAPE DESIGN OF AN OPTIMAL COMFORTABLE PILLOW BASED ON THE ANALYTICAL HIERARCHY PROCESS

METHOD (6)

Gordon, S., Grimmer-Somers, K., & Trott, P. (2009)

Random – allocation block design 99 participants

Different pillow materials Polyester, foam-regular, foam-contour, latex, feather

Conclusion Latex pillow reduced the pain most

PILLOW USE: THE BEHAVIOUR OF CERVICAL PAIN, SLEEP QUALITY, AND PILLOW COMFORT IN SIDE SLEEPERS (5)

Gordon, S., Grimmer-Somers, K., & Trott, P. (2010)

Own pillow and five trial pillows Polyester, foam-contour, foam-regular, feather, latex

Field trial 106 participants

Conclusion Feather and foam contour pillows produce more waking pain Latex pillows produced less waking pain

YOUR PILLOW MAY NOT GUARANTEE A GOOD NIGHT’S SLEEP OR SYMPTOM-FREE WAKING (6)

SLEEP QUALITY

Gordon, S., Grimmer-Somers, K., & Trott, P. (2009)

Random allocated block design 99 participants

Tested five different pillows on sleep quality Polyester, foam regular, foam contour, feather, latex

Conclusion Latex pillows provided best sleep quality Feather pillows provided worst sleep quality

PILLOW USE: THE BEHAVIOUR OF CERVICAL PAIN, SLEEP QUALITY, AND PILLOW COMFORT IN

SIDE SLEEPERS (5)

Setokawa, H., Hayashi, M., & Hori, T. (2007)

Effect of body temperature

Controlled comparative study 7 participants

Water pillow temperatures Room temperature 26°C Ice temperature 16°C

Conclusion Sleep quality improved with cooling occipital region

FACILITATING EFFECT OF COOLING THE OCCIPITAL REGION ON NOCTURNAL SLEEP (5)

SPINAL ALIGNMENT

Gordon, S., Grimmer-Somers, K. & Trott, P. (2011).

Randomized-block design 95 participants

Pillow type and segmental stability Polyester, foam regular, foam contour, latex, feather

Conclusion Feather pillow provided least stability

A RANDOMIZED, COMPARATIVE TRIAL: DOES PILLOW TYPE ALTER CERVICO-THORACIC SPINAL POSTURE WHEN SIDE LYING? (6)

To decrease pain, pillows should have multiple dimensions (Liu et al., 2011)

Latex pillows increase sleep quality (Gordon et al., 2009; 2010)

Feather pillows decrease sleep quality and increase pain (Gordon et al., 2009; 2010)

Cooling the occipital region promotes sleep (Setokawa et al., 2007)

Feather pillows produce the least amount of segmental stability (Gordon et al., 2011)

PILLOW CONCLUSIONS

MATTRESS RESULTS AND DISCUSSION

24 ARTICLES

PAIN REDUCTION

10 ARTICLES

Author (year) PEDro Score Study Design Number of Patients

Present Condition Outcome Conclusion

1.      

10 Randomized, blinded, controlled trial

313 Greater than/equal to three months chronic back pain while lying in bed or on rising.

Pain reduction The medium-firm mattresses was more likely to improve degree of disability than patients who used the firm mattresses.  Patients with chronic back pain will benefit more from a medium firm mattress than a firm mattress.

2. 8 Randomized Controlled Trial

12 Asymptomatic Pain reduction No significant statistical differences between the two mattresses in regards to any of the outcome measures; however, the pressure relief-mattress reduced the number of high pressure points.

3 7 Randomized single-blinded clinical trial

160 Symptomatic Pain reduction When compared to the hard mattress, the waterbed and foam mattresses had a more positive influence on back pain and ADL performance.

4. 5 Controlled Trial 22 Symptomatic Pain reduction Significant decrease in back pain, back stiffness, and shoulder pain as well as an increase in sleep quality and comfort with the prescribed sleep surface.

Kovacs, F. M. et al., (2003)

Randomized-blind control trial 313 participants

Intervention 155 allocated to medium-firm mattress 158 allocated to firm mattress

Outcome Measure Visual Analog Scale (VAS) Roland Morris questionnaire

Conclusion Medium-firm mattress reduced degree of disability

EFFECT OF FIRMNESS OF MATTRESS ON CHRONIC NON-SPECIFIC LOW BACK PAIN: RANDOMIZED DOUBLE-BLIND

CONTROL MULTICENTER TRIAL

Vaughn McCall, W., Boggs, N., & Letton, A. (2012).

Randomized controlled trial 12 participants

Intervention Compared conventional mattress and a 7 zone pressure relief mattress 2 week baseline, 2 week test for each mattress (total of 6 weeks)

Outcome Measures VAS Actigraphy and pressure mapping

Conclusion No statistical differences with regards to pain

CHANGES IN SLEEP AND WAKE IN RESPONSE TO DIFFERENT SLEEPING SURFACES: A PILOT STUDY

SLEEP QUALITY

18 ARTICLES

Author (year) PEDro Score Study Design Number of Patients

Present Condition Outcome Conclusion

1 6 Randomized ControlTrial

10 Asymptomatic Sleep quality  No significant difference in sleep quality between mattress types.. An adequate mattress should be soft enough to avoid excess compression of joints to prevent compression of neurovascular system

2 6 Non-randomized controlled trial

23 Asymptomatic Sleep quality Change in mattress pressure had little physiologic significance, despite the significant changes in spinal alignment.  Subjects reported higher comfort with higher inflation measures.

3 6 Non-randomized controlled trial

75 Asymptomatic Sleep quality As hardness increases (area under the load/deflection decreases) the perception of firmness increases. As pressure/hardness increases, subjective comfort increases. 

4 6 Experimental 24 Asymptomatic, patients with insomnia

Sleep quality Proximal warming improved deep sleep. and distal improved REM.

Bader, G. G., & Engdal, S. (2000)

Randomized-controlled trial 10 participants

Intervention Compared soft and firm mattress 3 nights on own mattress, 5 nights on each test mattress

Outcome Measures Questions regarding fatigue, discomfort, and pain Polysomnography

Conclusion No global mattress design for global population

THE INFLUENCE OF BED-FIRMNESS ON SLEEP QUALITY

Lahm, R., & Iaizzo, P. A. (2002)

Non-randomized controlled trial 23 participants

Interventions Adjustable air bladder (low, medium, high) Participants remained lying for 30 minutes

Outcome Measure Subjective comfort pertaining to bed pressure EMG, heart rate, blood pressure

Conclusions Subjects reports higher comfort with higher inflation pressures

PHYSIOLOGIC RESPONSES DURING REST ON A SLEEP SYSTEM AT VARIED DEGREES OF FIRMNESS IN A NORMAL POPULATION

SPINAL ALIGNMENT

4 ARTICLES

Author (year) PEDro Score Study Design Number of Patients

Present Condition Outcome Conclusion

1 8 Controlled Trial 18 Asymptomatic Spine alignment The least amount of pressure was seen in mattress A (Perfect Contour Extraordinaire Dorchester by King Koil and the most pressure was seen in mattress D(Perfect Sleeper Southdale by Serta). Mattress D also demonstrated the least spinal distortion.

2 5 Controlled Trial 25 Asymptomatic Spine alignment Neither a soft nor firm mattress is sufficient to support spine alignment. Too soft of a mattress results in cervical spine being in a higher position than the pelvis.

3 5 Quasi-experimental

10 Asymptomatic Spine alignment Use of inflated lumbar cushion allowed for more homogenous distribution of pressure and decreased pressure in the thoracic and pelvic regions.

4 5 Multicenter controlled trial

18 Asymptomatic Spine alignment Most favored mattress by the subjective ratings was the mattress in which the spinal curvature in lying was most similar to that in standing.  Average pressure at the shoulder was higher in softer beds. The study found that firmness had to be extended in order to increase in patient comfort.

DeVocht, J. , Wilder, D., Bandstra, E., & Spratt , K. (2006)

Randomized controlled trial 18 participants

Intervention Compared four “top of the line” mattresses in side-lying

Perfect contour extraordinaire Dorchester Beauty rest calibri-firm Posture-pedic Perfect sleeper

Outcome Measures Postural distortion measured by making spinous processes

Conclusion Perfect Sleeper demonstrated least amount of spinal distortion

BIOMECHANICAL EVALUATION OF FOUR DIFFERENT MATTRESSES

Leilnahari, K., Fatouraee, N., Khodalotfi, M., Sadeghein, M. A., & Amin Kashani, Y. (2011)

Controlled trial 25 participants

Intervention Compared soft (polyurethane foam), firm, and custom made mattress Markers placed on spinous processes C7-L2 and L5

Outcome Measure Spine alignment measured in side-lying Two digital cameras captured angle of vertebrae

Conclusion Customized inflatable mattress is conducive to maintain spine alignment

SPINE ALIGNMENT IN MEN DURING LATERAL SLEEP POSITION: EXPERIMENTAL STUDY AND

MODELING

Medium-firm mattresses provide the best outcomes for improving sleep quality and reducing back pain (Kovacs et al., 2003; Lahm & Iaizzo, 2002)

Individualized sleep systems help to improve spinal alignment and sleep quality (Bader et al., 2000; Leilnahari et al., 2011)

Proximal warming can be used to decrease early morning waking and enhance deep sleep (Raymann et al., 2008)

MATTRESS CONCLUSIONS

To enhance sleep quality: Rubber (latex) pillows enhance sleep quality Cooling the occipital region can enhance sleep Medium-firm mattresses provide best outcomes for increased sleep

quality

To reduce pain: Pillows should have multiple dimensions Medium-firm mattresses produce the best outcomes for reducing pain Proximal warming of mattresses can reduce early morning pain

To promote spinal alignment: No sufficient evidence relating cervical spine stability and pillow Individualized mattress systems can enhance spinal alignment

CLINICAL SIGNIFICANCE AND RECOMMENDATIONS FOR HEALTH CARE

PROFESSIONALS

Limited literature regarding pillowsRepeated population of subjects amongst studiesNo gold standard for subjective measurements (heterogeneous)No universal level of mattress firmness amongst studies

LIMITATIONS

Purpose of study Provide a systematic review of current literature of pillows and

mattresses in relation to: Improving spinal alignment Decreasing pain Promoting sleep quality

Determine best mattress and pillows based on the current literature Help guide health care professionals

SUMMARY

Applied Ergonomics Conference Accepted for poster presentation March 16-19, 2015 Nashville, Tennessee

FUTURE FOR THE STUDY

Ahmed RadwanThomas Crist

ACKNOWLEDGEMENTS

QUESTIONS?

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N o r m a n d , M . , D e s c a r r e a u x , M . , P o u l i n , C . , R i c h e r , N . , M a i l h o t , D . , B l a c k , P. , & D u g a s , C . ( 2 0 0 5 ) . B i o m e c h a n i c a l e f f e c t s o f a l u m b a r s u p p o r t i n a m a t t r e s s .   J o u r n a l O f T h e C a n a d i a n C h i ro p r a c t i c A s s o c i a t i o n ,   4 9 ( 2 ) , 9 6 - 1 0 1 .

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P o r t n e y, L . G . , & Wa t k i n s , M . P. ( 2 0 0 9 ) . F o u n d a t i o n s o f c l i n i c a l r e s e a r c h : a p p l i c a t i o n s t o p r a c t i c e ( 3 r d e d . ) . U p p e r S a d d l e R i v e r, N . J : P e a r s o n / P r e n t i c e H a l l

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To n e t t i , L . L . , M a r t o n i , M . M . , & N a t a l e , V. V. ( 2 0 11 ) . E f f e c t s o f d i f f e r e n t m a t t r e s s e s o n s l e e p q u a l i t y i n h e a l t h y s u b j e c t s : a n a c t i g r a p h i c s t u d y.   B i o l o g i c a l R h y t h m R e s e a rc h ,   4 2 ( 2 ) , 8 9 - 9 7 .

Va n D e u n , D . , Ve r h a e r t , V. , Wi l l e m e n , T. , Wu y t s , J . , Ve r b r a e c k e n , J . , E x a d a k t y l o s , V. , H a e x , B . , a n d Va n d e r S l o t e n , J . ( 2 0 1 2 ) . B i o m e c h a n i c s - b a s e d a c t i v e c o n t r o l o f b e d d i n g s u p p o r t p r o p e r t i e s a n d i t s i n f l u e n c e o n s l e e p .   Wo r k ,   4 1 1 2 7 4 - 1 2 8 0 .

Va u g h n M c C a l l , W. , B o g g s , N . , & L e t t o n , A . ( 2 0 1 2 ) . C h a n g e s i n s l e e p a n d w a k e i n r e s p o n s e t o d i f f e r e n t s l e e p i n g s u r f a c e s : a p i l o t s t u d y.   A p p l i e d E rg o n o m i c s ,   4 3 ( 2 ) , 3 8 6 - 3 9 1 .

Ve r h a e r t , V. , H a e x , B . , D e Wi l d e , T. , B e r c h m a n s , D . , Ve r b r a e c k e n , J . , d e Va l c k , E . , & Va n d e r S l o t e n , J . , ( 2 0 11 ) . E rg o n o m i c s i n b e d d e s i g n : t h e e f f e c t o f s p i n a l a l i g n m e n t o n s l e e p p a r a m e t e r s . E rg o n o m i c s , 5 4 ( 2 ) , 1 6 9 - 1 7 8 . D o i : 1 0 . 1 0 8 0 / 0 0 1 4 0 1 3 9 . 2 0 1 0 . 5 3 8 7 2 5 .

We l l s , M . , & Va u g h n , B . ( 2 0 1 2 ) . P o o r s l e e p c h a l l e n g i n g t h e h e a l t h o f a n a t i o n . N e u ro d i a g n o s t i c J o u r n a l , 5 2 ( 3 ) , 2 3 3 - 2 4 9 .

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