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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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