Page 107 - JSOM Winter 2022

TABLE 2 Characteristics of Studies Examining Associations between Musculoskeletal Symptoms/MSI Injuries and Sleep Quality/Quantity in
Military Personnel
Study Participants Sleep Assessment Injury Assessment Results
Gregg et al. 126 US Soldiers Survey that included Traumatic or overuse Traumatic injury: 3.7 higher odds of traumatic
2002 39 at US Army question on trouble falling injuries obtained injury if had trouble falling asleep.
Sergeant Major asleep or staying asleep. from medical records No difference in overuse injuries between those
Academy screening. who reported trouble falling asleep and those
who reported no trouble falling asleep.
Kazman et al. 2,335 female US Two item version of Self-report of seeking Poor sleep: 44% sought care for injury
2015 40 Soldiers, active Pittsburg Insomnia Rating medical care for a Good sleep: 27% sought care for injury
duty, reserves, or Scale: “In the past week how physical activity-related RR (poor/good) = 1.63 (95%CI = 1.41–1.90)
National Guard much were you bothered by injury in last 6 months.
lack of energy because of
poor sleep?”; “Over the past
week how would you rate
your satisfaction with your
sleep?” (4 point Likert scale
for responses).
Shattuck et al. 739 US Navy Survey that included Nordic Musculoskeletal In multivariate analysis (including age, gender,
2016 41 personnel on USS question: “Over the last Questionnaire. Subjects body mass index, use of sleep medication, and
Nimitz while in month, how many hours of reported musculoskeletal other variables) and shorter nighttime sleep
port sleep on average did you get problems over last week, duration was a significant predictor of the
each night? (Example 7.5 past year and whether or occurrence of musculoskeletal symptoms:
hours).” not problem(s) prevented 1) over the past 7 days, 2) over the last 12
carrying out normal months, and 3) that prevented carrying out
duties. normal duties.
Kardouni et 1,092,420 US Clinically diagnosed sleep Incident or recurrent 1. Incident LBP:
al. 2016 42 Army Soldiers disorders determined from clinically diagnosed LBP With sleep disorder: 101cases/1000 person-
on active duty ICD-9 codes in medical from ICD-9 codes in years.
during 2002 to records. medical records. Without sleep disorder: 122/1000 person-years.
2011 Incident rate ratio: 0.80, 95%CI = 0.78–0.81.
2. Recurrent LBP
With sleep disorder: 38 cases/1000 person-
years.
Without sleep disorder: 31/1000 person-years.
Incident rate ratio: 1.29, 95%CI = 1.25–1.29.
Kovcan et al. 129 Slovenian “Sleep quality” (not well Current musculoskeletal Sleep quality was not associated with MSI
2019 43 soldiers in an defined) complaints (data not presented).
infantry regiment
Grier et al. 7,576 US Special Survey that included Survey that included See Figure 3. As the self-reported number of
2020 13 Forces Operators question: “How many hours question: “How many hours of nighttime sleep decreased, the self-
and support staff of actual sleep did you musculoskeletal injuries reported number of injuries increased. After
get at night? (This may be have you sustained in the adjustment for age, sex, and exercise duration,
different than the number of past 12 months?” this relationship was still significant.
hours you spent in bed).”
Ruan et al. 44 563 recruits in Score on PSQI just prior to Soft tissue injury (skin, See Figure 2. Those with poor sleep quality
Chinese Army basic training muscle, tendon, nerve, before basic training (PSQI score ≥7) were
Basic Training or blood vessel trauma), more likely to experience diagnosed injury
osteoarticular injury during basic training. After adjustment for age,
(acute fracture, stress ethnicity, education and family income, the
fracture, and joint relationship was still significant.
injuries), and other
injuries (those not
fitting the other two
classifications).
Ritland et al. 82 US Army Sleep quality on PSQI; Survey question: “Do See Table 3. Sleep quality (PSQI or 100-point
2021 45 Rangers Insomnia Severity Scale; you currently have scale) was lower and insomnia severity
sleep quality on 100-point any musculoskeletal higher among those reporting current MSI.
scale; average sleep duration injuries?” Self-reported sleep duration did not differ
over last week. significantly between those reporting injuries
and those not.
95% CI = 95% confidence interval, ICD-9 = International Classification of Diseases Revision 9, LBP = low back pain, MSI = musculoskeletal
injury, PSQI = Pittsburg Sleep Quality Index, RR = risk ratio, US = United States, USS = United States Ship

tissue, sleep restriction over three weeks (5.6 hours/day) has Sleep Environment and Schedule Considerations
been shown to rapidly affect biomarkers of bone turnover in a
manner indicating decreased bone formation with no change The sleep environment and the timing of sleep can affect
in bone resorption. 59,60 Collectively, these physiological pro- sleep quality and duration. The sleep environment includes
cesses could contribute to increased risk of MSI during periods air temperature, humidity, clothing, bedding, mattress, pres-
of low sleep quality or duration. ence/absence of electronic devices, and noise level. Extremes of
temperature lead to more wakefulness, lower sleep efficiency,

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