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Case Reports in Medicine
Volume 2016, Article ID 9412315, 6 pages
http://dx.doi.org/10.1155/2016/9412315

Case Report
Sacral Stress Fracture following the Bone Union of
Lumbar Spondylolysis
Tatsuro Sasaji,1 Hideki Imaizumi,1 Hiroyuki Takano,1 Hideo Saitoh,1
Taishi Murakami,1 Ryuichi Kanabuchi,1 and Motohiko Sekiya2
1

Department of Orthopedic Surgery, Osaki Citizen Hospital, 3-8-1 Furukawa Honami, Osaki-shi, Miyagi 989-6183, Japan
Sekiya Orthopedic Surgery, 5-1-19 Furukawa Ekimae Odori, Osaki-shi, Miyagi 989-6182, Japan

2

Correspondence should be addressed to Tatsuro Sasaji; taturosasaji@gmail.com
Received 24 July 2016; Accepted 9 November 2016
Academic Editor: Simon Ching-Shun Kao
Copyright © 2016 Tatsuro Sasaji et al. This is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
While 22 articles have reported on sacral stress fractures, it is a rare injury and its etiology is not well known. We present thecase of a 16-year-old male who presented with low back pain in 2015. He was a high school soccer player with a previous historyof a bilateral L5 lumbar spondylolysis in 2014. The patient refrained from soccer and wore a brace for six months. Two months
after restarting soccer, he again complained of low back pain. After 1 year, a lumbar spine computed tomography revealed the bone
union of the spondylolysis. At his first visit to our hospital, his general and neurological conditions were normal and laboratory data
were within the normal range. Sacral coronal magnetic resonance imaging (MRI) of the left sacral ala revealed an oblique lineal
signal void surrounding bone marrow edema. Based on his symptoms, sports history, and MRI, he was diagnosed with a sacralstress fracture. He again refrained from soccer; his low back pain soon improved, and, after 1 year, the abnormal signal change had
disappeared on sacral MRI. Recurrent low back pain case caused by a sacral stress fracture occurring after the bone union of lumbar
spondylolysis is uncommon.

1. Introduction
Lumbar spondylolysis is the most significant cause of low
back pain in high school and college football players [1].
Lumbar spondylolysis is considered to be a form of stressfracture, the development of which is frequently associatedwith vigorous sports activities during the growth period [2].
In an early stage of lumbar spondylolysis, an orthosis leads tobone union [3].
Matheson et al. reported that, among 320 athletes witha bone scan-positive stress fracture, a pelvic fracture wasreported in only five cases (1.6%) [4]. A sacral stress fracture
was first reported by Czarnecki et al., and, to the best of
our knowledge, 46 cases have been reported in 22 articles
till date [5–26]. We present the case of a patient with asacral stress fracture following the bone union of lumbar
spondylolysis and report on the radiological findings andtreatment course. We considered the two stress fractures(lumbar spondylolysis and sacral stress fracture) causing low

back pain that happened in one patient to be a very rare
condition. The patient and his family gave consent to submit
these data for publication.

2. Case Report
A 16-year-old male presented to our hospital with low backpain. He was a soccer player and had a history of lumbar
spondylolysis that had been conservatively treated by aprevious doctor. A period of rest and wearing a brace wereadvised in 2014. A lumbar computed tomography (CT) scan
at his first visit to a previous doctor’s clinic indicated that
there were bilateral fracture lines in the L5 isthmus (Figures
1(a)–1(c)). His low back pain soon improved, and, after 10months, he started playing soccer again in 2015. However, 2months later, his low back pain recurred, and a 1-year followup lumbar CT indicated that his spondylolysis had united
without displacement (Figures 2(a)–2(c)). He had no pasthistory of malignant diseases or the use of steroid drugs.

2Case Reports in Medicine

L4

L4

L
(a)

(b)

(c)

Figure 1: Reconstructed computed tomography (CT) scan of the lumbar spine from the first visit to a previous doctor’s office. (a) Rightparasagittal reconstructed CT image. (b) Left parasagittal reconstructed CT image. (c) Axial CT image at L5 level. Fissures (black arrows) inthe bilateral pars interarticularis of the L5 can be seen (a, b, c). These radiological findings indicated a bilateral spondylolysis of the L5.

L4

L4

L
(a)

(b)

(c)

Figure 2: A 1-year follow-up reconstructed computed tomography (CT) scan of the lumbar spine after initial conservative treatment. (a)Right parasagittal reconstructed CT image. (b) Left parasagittal reconstructed CT image. (c) Axial CT image at L5 level. The radiologicalfindings indicated that the bilateral spondylolysis of the L5 had united (a, b, c).

2.1. Physiological Examination. The patient was 165 cm talland weighed 50 kg. He complained of left sacral pain and had
tenderness in the same region. A neurological examination
at his first visit to our hospital indicated no neurologicalsymptoms.
2.2. Laboratory Examination. Laboratory findings indicateda high alkaline phosphatase level and other tests were within
normal limits (Table 1). There was no inflammatory reaction
and infectious diseases were excluded.
2.3. Radiological Findings. Sacral magnetic resonance imaging (MRI) obtained by the previous doctor showed a lowintensity T1-weighted image of the left second sacral ala anda high-intensity T2-weighted image and a short TI inversion
recovery (STIR) image (bone marrow edema) compared with

Table 1: Laboratory data.
White blood cell (/𝜇L, 33–81)
Alkaline phosphatase (U/L, 115–359)
Lactate dehydrogenase (U/L, 119–229)
Sodium (mEq/L, 138–146)
Chlorine (mEq/L, 99–109)
Potassium (mEq/L, 3.6–4.9)
Calcium (mg/dL, 8.7–10.3)
Phosphorus (mg/dL, 2.5–4.7)
Creatine kinase (U/L, 62–287)
C-reactive protein (mg/dL, 0–0.3)

4540
494
189
144
104
4
9.4
4.2
120
0.03

the right side. An oblique low lineal appearance could beseen in the bone marrow edema (Figures 3(a)–3(d)). On thebasis of his sport history, laboratory data, past history, andCase Reports in Medicine

3

S2

S2

L

L

(a)

(b)

S2

L

L
(c)

(d)

Figure 3: Magnetic resonance image of the sacrum at the first visit to our hospital. (a) Coronal plane on a T1-weighted image. (b) Coronalplane on a T2-weighted image. (c) Coronal plane on a short TI inversion recovery (STIR) image. (d) Axial plane at the S2 level on a STIR
image. The left sacral ala on a T1-weighted image shows a low intensity (a), a T2-weighted image shows a high intensity (b), and on a STIR
image shows a high intensity (c) compared with the right sacral ala. These radiological findings indicated bone marrow edema. Obliquelineal signal void (white arrows) can be seen in the bone marrow edema; these are fracture lines. An axial plane on a STIR image shows alow-intensity area (white arrow) surrounded by a high-intensity area in the left ventral surface of the sacral ala (d).

S2

L
(a)

L
(b)

Figure 4: Magnetic resonance images of the sacrum one year after conservative treatment. (a) Coronal plane on a short TI inversion recovery(STIR) image. (b) Axial plane at the S2 level on a STIR image. Coronal plane (a) and axial plane at the S2 level (b) on a STIR image show noabnormal signal intensity. These radiological findings indicated bone union of the sacral stress fracture.

4radiological findings, the patient was diagnosed with a sacralstress fracture. Therefore, he was managed nonoperatively,
and he discontinued soccer.
2.4. Treatment Course. His lower back pain soon improved
and within one year he had returned to activities of dailyliving without lower back pain. However, he retired from thesoccer club for fear of a recurrent stress fracture. A 1-year
follow-up sacral STIR image showed that the abnormal signal
appearance in the left second sacral ala had disappeared (Figures 4(a) and 4(b)). Based on the fact that his symptoms had
disappeared and on the radiological findings, we considered
his sacral stress fracture as united.

3. Discussion
Kaneko et al. identified seven (2.3%) fractures in 311 sportsrelated low back pain cases [25]. We reviewed 46 detailed
case reports of sacral stress fractures of which 15 cases
were male and 31 cases were female (Table 2). The average age was 21.9 years (range 9–46 years). The right side
was affected in 23 cases and the left side in 22 casesand one case was bilateral. Reported sports were longdistance running, cross-country running, basketball, andsoccer. Our case can be included here as a proper sacral stressfracture.
In previous reports, the diagnosis of a sacral stressfracture was made based on a sports history and radiological findings. The reported main radiological methods
were a bone scintigram and MRI. According to Grier etal., suggestive MRI findings of a fatigue fracture were acentral lineal signal void on both T1- and T2-weighted
sequences surrounded by diffuse low marrow signals on T1
images and increased signals on T2 images [8]. Previous
studies that documented a sacral stress fracture reported
MRI findings with a lineal low-intensity appearance in thehigh signal intensity area on T2-weighted sequences [8, 10,
11, 14, 17–20, 22–26]. The MRI findings of this case werecompatible based on the radiological findings of previous
reports.
While 22 articles have reported on sacral stress fractures,some authors reported a sacral stress fracture as an uncommon injury, although it is not rare based on the number ofprevious reports [5–26]. The common criteria regarding asacral stress fracture were young healthy athletes, MRI and/or
bone scintigraphy as a diagnostic tool, and pain relief uponcessation of sports [5–26]. Based on the previous reports, weconsidered that complicated diagnosis and easy improvement
by rest left sacral stress fracture not diagnosed and made it a
not well-known disease for orthopedic doctors.
In our review of 37 cases of sacral stress fracture including
descriptions of a past stress fracture (Table 3), five cases had
a previous history of a stress fracture [10, 12, 14, 17, 18].
Three cases involved the tibia, one involved the metatarsal
and tibia, and one involved the sacrum [10, 12, 14, 17, 18].
To our knowledge, this case is the first report of a sacralstress fracture after union of a lumbar spondylolysis and we
consider it to be a rare pathological condition.

Case Reports in Medicine
Table 2: Review of reports.
Reference Side
[5]
[6]
[7]
[8]
[8]
[9]
[9]
[9]
[10]
[10]
[10]
[11]
[12]
[13]
[14]
[14]
[14]
[14]
[14]
[14]
[14]
[14]
[15]
[16]
[17, 18][17, 18][17, 18][17, 18][17, 18]
[19]
[20]
[20]
[21]
[21]
[22]
[22]
[23]
[24]
[25]
[25]
[25]
[25]
[25]
[25]
[25]
[26]

Left
Right
Right
Left
Left

Sex
Male
FemaleMale
FemaleMaleSportsLong-distance runner
RunnerLong-distance runner
Runner
None
Cross-country
and distance
Left Female
runnerRight Female Cross-country and distancerunnerLeft Female
Multiple sports
Right Female
Cross-country runner
Right Female
Long-distance runner
Right Female
Cross-country runner
Right
Male
Basketball
Left
Male
Long-distance runner
Right
Male
RunnerLeft Female
SoccerLeft Female
Basketball
Left Female
RunnerLeft Female
Cross-country runner
Left Female
Jogging
Right Female
Jogging
Right Female
Cross-country runner
Left Female
Cross-country runner
Left Female
Volleyball
Left
Male
Long-distance runner
Left
Male
Long-distance runner
Left Female
Long-distance runner
Left Female
Long-distance runner
Right Female
Long-distance runner
Right Female
Long-distance runner
Right Female
TennisRight Female
RunnerRight Female
Cross-country runner
Left
Male
Long-distance runner
Left
Male
RunnerLeft Female
Basketball
Left
Male
Long-distance runner
Right Female
Marathon
Right
Male
Professional hockey
Right
Male
SoccerRight Female
SoccerRight Female Softball and athletic sports
Right Female
Softball
Bilateral Male
Basketball
Right Female
Basketball
Left
Male
Baseball
Right Female
Mounted police officer

Age(year)
26
28
40
14
9
21
21
17
20
21
20
20
19
28
21
20
45
22
41
19
20
21
16
21
20
21
21
20
21
46
21
18
26
23
16
17
34
27
15
18
10
15
14
16
15
26

Case Reports in Medicine

5

Table 3: Review of reports.
Reference
[5]
[7]
[8]
[8]
[9]
[9]
[9]
[10]
[10]
[10]
[11]
[12]
[13]
[14]
[14]
[14]
[14]
[14]
[14]
[14]
[14]
[15]
[16]
[17, 18][17, 18][17, 18][17, 18][17, 18]
[20]
[20]
[21]
[21]
[22]
[22]
[23]
[24]
[26]

A history of stress fracture
None
None
None
None
None
None
None
None
Right sacrum
None
None
Right tibia
None
Metatarsal, bilateral tibia
None
None
None
None
None
None
None
None
None
None
Bilateral tibia
Right tibia
None
None
None
None
None
None
None
None
None
None
None

Competing Interests
The authors declare that there are no competing interests
regarding the publication of this paper.

References[1] J. Iwamoto, H. Abe, Y. Tsukimura, and K. Wakano, “Relationship between radiographic abnormalities of lumbar spine
and incidence of low back pain in high school and college
football players: A Prospective Study,” American Journal ofSports Medicine, vol. 32, no. 3, pp. 781–786, 2004.
[2] T. Yamane, T. Yoshida, and K. Mimatsu, “Early diagnosis oflumbar spondylolysis by MRI,” The Journal of Bone & Joint
Surgery—British Volume, vol. 75, no. 5, pp. 764–768, 1993.

[3] K. Sairyo, “State of the art of the lumbar spondylolysis withrespect to early diagnosis and conservative treatment,” Journalof Spine Research, vol. 1, pp. 30–40, 2010 (Japanese).
[4] G. O. Matheson, D. B. Clement, D. C. Mckenzie, J. E. Taunton,
D. R. Lloyd-Smith, and J. G. MacIntyre, “Stress fractures inathletes. A study of 320 cases,” American Journal of Sports
Medicine, vol. 15, no. 1, pp. 46–58, 1987.
[5] D. J. Czarnecki, E. W. Till, and J. L. Minikel, “Unique sacral stressfracture in a runner,” American Journal of Roentgenology, vol.
151, no. 6, p. 1255, 1988.
[6] M. B. Bottomley, “Sacral stress fracture in a runner,” British
Journal of Sports Medicine, vol. 24, no. 4, pp. 243–244, 1990.
[7] J. Schils and J.-P. Hauzeur, “Stress fracture of the sacrum,”
American Journal of Sports Medicine, vol. 20, no. 6, pp. 769–770,
1992.
[8] D. Grier, S. Wardell, J. Sarwark, and A. K. Poznanski, “Fatigue
fractures of the sacrum in children: two case reports and areview of the literature,” Skeletal Radiology, vol. 22, no. 7, pp.
515–518, 1993.
[9] E. G. McFarland and C. Giangarra, “Sacral stress fractures inathletes,” Clinical Orthopaedics and Related Research, no. 329,
pp. 240–243, 1996.
[10] D. J. Eller, D. S. Katz, A. G. Bergman, M. Fredericson, and C.
F. Beaulieu, “Sacral stress fractures in long-distance runners,”
Clinical Journal of Sport Medicine, vol. 7, no. 3, pp. 222–225, 1997.
[11] H. C. Crockett, J. M. Wright, M. W. Madsen, J. E. Bates, H. G.
Potter, and R. F. Warren, “Sacral stress fracture in an elite college
basketball player after the use of a jumping machine,” American
Journal of Sports Medicine, vol. 27, no. 4, pp. 526–528, 1999.
[12] S. Miyazaki, T. Tomatsu, and Y. Nakamura, “Fatigue fractureof the sacrum in long distance runner,” Japanese Journal of
Orthopaedic Sports Medicine, vol. 8, pp. 83–85, 2000 (Japanese).
[13] K. Delvaux and R. Lysens, “Lumbosacral pain in an athlete,”
American Journal of Physical Medicine & Rehabilitation, vol. 80,
no. 5, pp. 388–391, 2001.
[14] A. W. Johnson, C. B. Weiss Jr., K. Stento, and D. L. Wheeler,“Stress fractures of the sacrum. An atypical cause of low backpain in the female athlete,” The American Journal of Sports
Medicine, vol. 29, no. 4, pp. 498–508, 2001.
[15] M. K. Shah and G. W. Stewart, “Sacral stress fractures: anunusual cause of low back pain in an athlete,” Spine, vol. 27, no.
4, pp. E104–E108, 2002.
[16] H. Fukushima, “Stress fracture of the sacrum in a long distancerunner-case report and review of the literature,” Japanese
Journal of Orthopaedic Sports Medicine, vol. 12, pp. 502–505,
2004 (Japanese).
[17] Y. Kobayashi, “Stress fracture of the sacrum in long-distancerunners: report of three cases,” Clinical Orthopedic Surgery, vol.
39, pp. 961–965, 2004 (Japanese).
[18] Y. Miyata, Y. Kobayashi, and Y. Takahashi, “Sugawa I: stressfractures in the sacrum in semi-professional long-distancerunners,” Japanese Journal of Orthopaedic Sports Medicine, vol.
25, pp. 427–431, 2006 (Japanese).
[19] R. T. Silva, A. De Bortoli, C. F. S. Laurino, R. J. Abdalla, and M.
Cohen, “Sacral stress fracture: an unusual cause of low back pain
in an amateur tennis player,” British Journal of Sports Medicine,vol. 40, no. 5, pp. 460–461, 2006.
[20] M. Fredericson, W. Moore, and S. Biswal, “Sacral stress fractures: magnetic resonance imaging not always definitive forearly stage injuries—a report of 2 cases,” American Journal ofSports Medicine, vol. 35, no. 5, pp. 835–839, 2007.

6[21] H. Fukushima, H. Okazaki, Y. Kodama, and J. Hasegawa, “Stressfracture of the pelvis in two cases of athletes,” Japanese Journalof Orthopaedic Sports Medicine, vol. 27, pp. 258–262, 2007
(Japanese).
[22] T. Sakata, “Sacral stress fractures diagnosed with MR imaging
in two young athletes,” Japanese Journal of Orthopaedic Sports
Medicine, vol. 15, pp. 287–290, 2007 (Japanese).
[23] L. M. R. Rodrigues, F. H. Ueno, E. S. Valesin Filho, E. N. Fujiki,
and C. Milani, “Sacral stress fracture in a runner: a case report,”
Clinics, vol. 64, no. 11, pp. 1127–1129, 2009.
[24] J. D. Southam, M. L. Silvis, and K. P. Black, “Sacral stress fracture
in a professional hockey player: a case report,” Orthopedics, vol.
33, article 846, 2010.
[25] H. Kaneko, G. Murakami, and K. Nishizawa, “Fatigue fracturesof the sacrum in adolescent athletes with low back pain,”
Orthopedic Surgery, vol. 65, pp. 451–455, 2014 (Japanese).
[26] D. A. Bednar and K. Almansoori, “Sacral stress fracture mimicking lumbar radiculopathy in a mounted police officer: casereport and literature review,” Global Spine Journal, vol. 5, no. 5,
pp. e69–e73, 2015.

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