eMedicine Specialties > Radiology > Musculoskeletal

Pelvis, Insufficiency Fractures

Author: Wilfred CG Peh, MD, MBBS, FRCP(Glasg), FRCP(Edin), FRCR, Clinical Professor, Faculty of Medicine, National University of Singapore; Senior Consultant Radiologist, Alexandra Hospital, Singapore
Contributor Information and Disclosures

Updated: Mar 25, 2009

Introduction

Background

Insufficiency fracture is a subgroup of stress fracture. Unlike the other subtype (ie, fatigue fracture), insufficiency fracture is caused by normal or physiologic stress upon weakened bone. Loss of bone trabeculae decreases the bone's elastic resistance.

Axial CT of the sacrum reveals fractures (arrows)...

Axial CT of the sacrum reveals fractures (arrows) in both sacral alae. Note the sclerosis of the adjacent bone.

[ CLOSE WINDOW ]
Axial CT of the sacrum reveals fractures (arrows)...

Axial CT of the sacrum reveals fractures (arrows) in both sacral alae. Note the sclerosis of the adjacent bone.


Axial CT of the pubis reveals insufficiency fract...

Axial CT of the pubis reveals insufficiency fractures (arrows) in both parasymphyseal regions. Total hip replacement is an additional predisposing causative factor.

[ CLOSE WINDOW ]
Axial CT of the pubis reveals insufficiency fract...

Axial CT of the pubis reveals insufficiency fractures (arrows) in both parasymphyseal regions. Total hip replacement is an additional predisposing causative factor.


Awareness is increasing concerning the occurrence of these fractures among older persons. Sites frequently affected by insufficiency fractures are the thoracic vertebra, the tibia, the fibula, and the calcaneus.1,2,3,4,5

Presentation

Demographics

  • Insufficiency fractures are estimated to occur in 1-5% of persons, depending on the referral population.
  • Insufficiency fractures are estimated to occur in 1% of women older than 55 years.
  • Insufficiency fractures predominantly affect women.
  • Most patients with insufficiency fractures are older than 60 years.
  • In various studies, the mean age ranges from 62-74 years.
  • In most patients, insufficiency fractures resolve or improve significantly with conservative management.
Natural history and presentation

A fracture represents the end result of the spectrum of a bone's response to an increasing level of stress. According to Wolff's law, stress that occurs beyond the bone's elastic range causes persistent plastic deformity as a result of microfractures. In this situation, osteoclastic resorption exceeds osteoblastic activity. A strong association exists between fractures of the sacrum and those of the pubic bone (parasymphysis, pubic rami). Pubic fractures may develop as a result of increased anterior arch strain secondary to initial failure of the posterior arch (sacrum).

The most common cause of insufficiency fracture is postmenopausal osteoporosis. Other important causes are senile osteoporosis, pelvic irradiation, corticosteroid therapy, and rheumatoid arthritis. Other reported causes are total hip replacement, Tarlov cyst, Paget disease, fibrous dysplasia, scurvy, osteopetrosis, primary biliary cirrhosis, lung transplantation, tabes dorsalis, vitamin D deficiency, and fluoride therapy.


Oh et al measured the risk of pelvic insufficiency fractures following pelvic irradiation in cervical cancer patients. The investigators found the 5-year cumulative incidence of pelvic insufficiency fractures in these patients to be 19.7%. They suggested that multibeam arrangements can be used to reduce both the volume and dose of radiation to the pelvic bone and thereby reduce the risk of pelvic fracture, especially in older women with low body weight.6

Physical examination
Typically, patients present with groin pain, low back pain, or buttock pain and restricted hip movement. One quarter of patients have multiple sites of pain. In most patients, pain is severe enough to render the patient nonambulatory. Usually, patients present with either no history of trauma or a history of low impact trauma and signs of insufficiency fracture are nonspecific or nonexistent. Neurologic deficit is rare. In patients who have undergone pelvic irradiation, local soft tissue complications, especially affecting the rectum, frequently are encountered. Typically, a discordance exists between symptoms, which may be severe, and physical signs, which may be mild or absent.

Treatment

Management is conservative and consists initially of bed rest, reduced weight bearing, and the use of simple analgesics for pain relief. Graded exercises are started once symptomatic improvement is observed. Prognosis is good; healing is expected within 4 months.

Imaging-guided sacroplasty has been described for the treatment of sacral insufficiency fractures. Sacroplasty is a procedure in which polymethylacrylate, a quick-setting bone cement, is injected into the fracture. This technique appears to be useful in providing symptomatic relief to affected patients.7,8

Preferred Examination

Clinical assessment does not provide a definitive diagnosis of insufficiency fracture. Imaging has an important role in the detection and diagnosis of insufficiency fractures of the pelvis.9,10

Cabarrus et al compared the sensitivities of CT and MRI in detecting pelvic insufficiency fractures and found MRI to be substantially better in detecting such fractures. In patients undergoing both imaging modalities, 128 of 129 (99%) of fractures were detected by MRI, whereas only 89 of 129 fractures (69%) were detected by CT.11

Bone scintigraphy and MRI are the imaging modalities of choice.12,13,14,15,16,17,11,18

CT provides further definition of the fracture, especially if MRI is unavailable or bone scintigraphy is inconclusive.

Limitations of Techniques

  • Bone scintigraphy: Bone scintigraphy relies on accurate interpretation of the uptake pattern. Bone scintigraphy is highly sensitive; however, atypical uptake patterns may be difficult to interpret. Abnormal uptake may persist for several months.
  • CT: CT may not accurately detect fractures oriented transversely.
  • MRI: MRI is sensitive for detection of fractures, soft tissue edema, and marrow changes. MRI may be better at demonstrating alternative diagnoses than bone scintigraphy or CT.

Differential Diagnoses

Bone Metastases

More on Pelvis, Insufficiency Fractures

Overview: Pelvis, Insufficiency Fractures
Imaging: Pelvis, Insufficiency Fractures
Follow-up: Pelvis, Insufficiency Fractures
Multimedia: Pelvis, Insufficiency Fractures
References
Further Reading
[ CLOSE WINDOW ]

References

  1. Davies AM, Bradley SA. Iliac insufficiency fractures. Br J Radiol. Apr 1991;64(760):305-9. [Medline].

  2. Finiels H, Finiels PJ, Jacquot JM, Strubel D. [Fractures of the sacrum caused by bone insufficiency. Meta-analysis of 508 cases]. Presse Med. Nov 1 1997;26(33):1568-73. [Medline].

  3. Gotis-Graham I, McGuigan L, Diamond T, et al. Sacral insufficiency fractures in the elderly. J Bone Joint Surg Br. Nov 1994;76(6):882-6. [Medline].

  4. Peh WCG, Davies AM. Stress fractures. In: Davies AM, Johnson K, Whitehouse RW. Imaging of the hip and bony pelvis. Berlin: Springer; 2006:247-66.

  5. Weber M, Hasler P, Gerber H. Insufficiency fractures of the sacrum. Twenty cases and review of the literature. Spine. Dec 1993;18(16):2507-12. [Medline].

  6. Oh D, Huh SJ, Nam H, Park W, Han Y, Lim do H, et al. Pelvic insufficiency fracture after pelvic radiotherapy for cervical cancer: analysis of risk factors. Int J Radiat Oncol Biol Phys. Mar 15 2008;70(4):1183-8. [Medline].

  7. Garant M. Sacroplasty: a new treatment for sacral insufficiency fracture. J Vasc Interv Radiol. Dec 2002;13(12):1265-7. [Medline].

  8. Pommersheim W, Huang-Hellinger F, Baker M, Morris P. Sacroplasty: a treatment for sacral insufficiency fractures. AJNR Am J Neuroradiol. May 2003;24(5):1003-7. [Medline].

  9. Peh WC, Khong PL, Yin Y, et al. Imaging of pelvic insufficiency fractures. Radiographics. Mar 1996;16(2):335-48. [Medline].

  10. Campbell SE, Fajardo RS. Imaging of stress injuries of the pelvis. Semin Musculoskelet Radiol. Mar 2008;12(1):62-71. [Medline].

  11. Cabarrus MC, Ambekar A, Lu Y, Link TM. MRI and CT of insufficiency fractures of the pelvis and the proximal femur. AJR Am J Roentgenol. Oct 2008;191(4):995-1001. [Medline].

  12. Blomlie V, Lien HH, Iversen T, et al. Radiation-induced insufficiency fractures of the sacrum: evaluation with MR imaging. Radiology. Jul 1993;188(1):241-4. [Medline].

  13. Blomlie V, Rofstad EK, Talle K, et al. Incidence of radiation-induced insufficiency fractures of the female pelvis: evaluation with MR imaging. AJR Am J Roentgenol. Nov 1996;167(5):1205-10. [Medline].

  14. Gibbon WW, Hession PR. Diseases of the pubis and pubic symphysis: MR imaging appearances. AJR Am J Roentgenol. Sep 1997;169(3):849-53. [Medline].

  15. Grangier C, Garcia J, Howarth NR, et al. Role of MRI in the diagnosis of insufficiency fractures of the sacrum and acetabular roof. Skeletal Radiol. Sep 1997;26(9):517-24. [Medline].

  16. Hosono M, Kobayashi H, Fujimoto R, et al. MR appearance of parasymphseal insufficiency fractures of the os pubis. Skeletal Radiol. Sep 1997;26(9):525-8. [Medline].

  17. Mammone JF, Schweitzer ME. MRI of occult sacral insufficiency fractures following radiotherapy. Skeletal Radiol. Feb 1995;24(2):101-4. [Medline].

  18. Kwon JW, Huh SJ, Yoon YC, Choi SH, Jung JY, Oh D, et al. Pelvic bone complications after radiation therapy of uterine cervical cancer: evaluation with MRI. AJR Am J Roentgenol. Oct 2008;191(4):987-94. [Medline].

  19. Adkins MC, Sundaram M. Radiologic case study. Insufficiency fracture of the acetabular roof in Paget''s disease. Orthopedics. Oct 2001;24(10):945, 1019-20. [Medline].

  20. Albertsen AM, Egund N, Jurik AG, Jacobsen E. Posttraumatic osteolysis of the pubic bone simulating malignancy. Acta Radiol. Jan 1994;35(1):40-4. [Medline].

  21. Angles F, Coscujuela A, Tramunt C, Gonzalez Panisello M, Portabella F. Complication of an insufficiency fracture of the acetabulum. Hip Int. Jul-Sep 2008;18(3):236-8. [Medline].

  22. Blake SP, Connors AM. Sacral insufficiency fracture. Br J Radiol. Oct 2004;77(922):891-6. [Medline].

  23. Christiansen CG, Kassim RA, Callaghan JJ, et al. Pubic ramus insufficiency fractures following total hip arthroplasty. A report of six cases. J Bone Joint Surg Am. Sep 2003;85-A(9):1819-22. [Medline].

  24. Huh SJ, Kim B, Kang MK, et al. Pelvic insufficiency fracture after pelvic irradiation in uterine cervix cancer. Gynecol Oncol. Sep 2002;86(3):264-8. [Medline].

  25. Karatas M, Basaran C, Ozgül E, Tarhan C, Agildere AM. Postpartum sacral stress fracture: an unusual case of low-back and buttock pain. Am J Phys Med Rehabil. May 2008;87(5):418-22. [Medline].

  26. Mumber MP, Greven KM, Haygood TM. Pelvic insufficiency fractures associated with radiation atrophy: clinical recognition and diagnostic evaluation. Skeletal Radiol. Feb 1997;26(2):94-9. [Medline].

  27. Ogino I, Okamoto N, Ono Y, et al. Pelvic insufficiency fractures in postmenopausal woman with advanced cervical cancer treated by radiotherapy. Radiother Oncol. Jul 2003;68(1):61-7. [Medline].

  28. Oliver TB, Beggs I. Defects in the pelvic ring as a cause of sacral insufficiency fractures. Clin Radiol. Dec 1999;54(12):852-4. [Medline].

  29. Peh WC. Intrafracture fluid: a new diagnostic sign of insufficiency fractures of the sacrum and ilium. Br J Radiol. Aug 2000;73(872):895-8. [Medline].

  30. Peh WC, Cheng KC, Ho WY, Chan IK. Transient bone marrow oedema: a variant pattern of sacral insufficiency fractures. Australas Radiol. May 1998;42(2):102-5. [Medline].

  31. Peh WC, Evans NS. Tarlov cysts--another cause of sacral insufficiency fractures?. Clin Radiol. Nov 1992;46(5):329-30. [Medline].

  32. Peh WC, Gough AK, Sheeran T, et al. Pelvic insufficiency fractures in rheumatoid arthritis. Br J Rheumatol. Apr 1993;32(4):319-24. [Medline].

  33. Peh WC, Khong PL, Ho WY. Case report: sacral insufficiency fractures masking malignancy. Clin Radiol. Jan 1997;52(1):71-2. [Medline].

  34. Peh WC, Khong PL, Ho WY, et al. Sacral insufficiency fractures. Spectrum of radiological features. Clin Imaging. Apr-Jun 1995;19(2):92-101. [Medline].

  35. Peh WC, Khong PL, Sham JS, et al. Sacral and pubic insufficiency fractures after irradiation of gynaecological malignancies. Clin Oncol (R Coll Radiol). 1995;7(2):117-22. [Medline].

  36. Peh WC, Ooi GC. Vacuum phenomena in the sacroiliac joints and in association with sacral insufficiency fractures. Incidence and significance. Spine. Sep 1 1997;22(17):2005-8. [Medline].

[ CLOSE WINDOW ]

Keywords

pelvis insufficiency fracture, pelvis fracture, pelvic fracture, fracture of pelvis, stress fracture, pubic bone, parasymphysis, pubic rami, unstable pelvic fracture

[ CLOSE WINDOW ]

Contributor Information and Disclosures

Author

Wilfred CG Peh, MD, MBBS, FRCP(Glasg), FRCP(Edin), FRCR, Clinical Professor, Faculty of Medicine, National University of Singapore; Senior Consultant Radiologist, Alexandra Hospital, Singapore
Wilfred CG Peh, MD, MBBS, FRCP(Glasg), FRCP(Edin), FRCR is a member of the following medical societies: American Roentgen Ray Society, British Institute of Radiology, International Skeletal Society, Radiological Society of North America, Royal College of Physicians, and Royal College of Radiologists
Disclosure: Nothing to disclose.

Medical Editor

Leon Lenchik, MD, Director, Densitometry Minifellowship, Assistant Professor, Department of Radiology, Wake Forest University Medical Center
Leon Lenchik, MD is a member of the following medical societies: American College of Radiology, American Roentgen Ray Society, and Radiological Society of North America
Disclosure: Nothing to disclose.

Pharmacy Editor

Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand
Disclosure: Nothing to disclose.

Managing Editor

William R Reinus, MD, MBA, FACR, Professor of Radiology, Temple University; Chief of Musculoskeletal and Trauma Radiology, Vice Chair, Department of Radiology, Temple University Hospital
William R Reinus, MD, MBA, FACR is a member of the following medical societies: Alpha Omega Alpha, American College of Radiology, American Roentgen Ray Society, Radiological Society of North America, and Sigma Xi
Disclosure: Nothing to disclose.

CME Editor

Robert M Krasny, MD, Consulting Staff, Department of Radiology, Resolution Imaging Medical Corporation
Robert M Krasny, MD is a member of the following medical societies: American Roentgen Ray Society and Radiological Society of North America
Disclosure: Nothing to disclose.

Chief Editor

Felix S Chew, MD, MBA, EdM, Professor, Department of Radiology, Vice Chairman for Radiology Informatics, Section Head of Musculoskeletal Radiology, University of Washington
Felix S Chew, MD, MBA, EdM is a member of the following medical societies: American Roentgen Ray Society, Association of University Radiologists, and Radiological Society of North America
Disclosure: Nothing to disclose.

 
 
HONcode

We subscribe to the
HONcode principles of the
Health On the Net Foundation

All material on this website is protected by copyright, Copyright© 1994- by Medscape.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.