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Three Part Question

In [patients with isolated fracture of the greater trochanter on plain film] does [three dimensional imaging] detect [clinically important intertrochanteric extension]?

Clinical Scenario

In patients who have isolated fracture of the greater trochanter seen on plain film, does further cross sectional imaging (CT or MRI) help diagnose occult unstable extension of the fracture

Search Strategy

Medline (1950 - 15.9.2020), EMBASE (1974 onwards - 15.9.2020) and Cochrane were searched with the following terms
(((Trochanter).ti OR (Trochanteric).ti) AND ((Fracture).ti OR (Fractures).ti)) AND ((Imaging).ti,ab OR (MRI).ti,ab OR (MR).ti,ab OR (Occult).ti,ab)

Search Outcome

88 publications found
26 relevant publications, 12 of which duplicates, one a literature review, leaving 13 publications comprising one case report and 12 retrospective cohort studies

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Noh J, Lee KH, Jung S, Hwang S. March 2019 South Korea	100 patients with isolated greater trochanter fracture on plain film with subsequent further imaging	Retrospective cohort	Proportion of patients with intertrochanteric extension and management	Intertrochanteric extension found in 90/100 patients. 62 patients (those with fracture extension across the medial cortex) were managed surgically.	Not directly stated whether study includes all patients with isolated GT fracture or only those requiring further imaging. The outcomes for those patients who had fracture extending across the medial cortex and were managed conservatively were not discussed.
Moon, N.H., Shin, W.C., Do, M.U. et al. 2018 South Korea	30 consecutive patients that had plain film demonstrating isolated GT# who then went on to have further imaging	Retrospective cohort	Intertrochanteric extension on subsequent imaging. Management.	Intertrochanteric extension found in 21/30 patients. 20 patients were managed surgically.	Not stated whether study includes all patients with isolated GT fracture or only those requiring further imaging.
Park JH, Shon HC, Chang JS, et al. 2018 South Korea	Patients undergoing MRI following isolated greater trochanter fracture seen on plain film	Retrospective cohort	Proportion of patients with intertrochanteric extension and management	Intertrochanteric extension found in 14/37 patients. Only 4 patients required surgical management.	Not stated whether study includes all patients with isolated GT fracture or only those requiring further imaging. Abstract only published
Thurston D.; Marson B.; Ollivere B.; Westbrook T.; Moran C. et al. Sept 2018 Uk	Consecutive patients with plain film demonstrating isolated GT#.	Retrospective cohort	Proportion of patients with intertrochanteric extension and management	Intertrochanteric extension found in 15/85 patients. 4 were managed surgically.	Abstract only published. Unclear how patients were selected for surgery.
Chung PH, Kang S, Kim JP, et al 2016 South Korea	Patients that had plain film demonstrating isolated GT# that then went on to have CT/MRI	Retrospective cohort			Study aims to compare MRI and CT rather than determine the incidence of fracture extension.
Wong WY, Chu PY, Chan SWC, Yeung TW, Yuen MK 2016 Hong Kong	Consecutive patients with plain film demonstrating isolated GT#.	Retrospective cohort	Proportion of patients with intertrochanteric extension when imaged with CT and management and outcome	Intertrochanteric extension found in 10/58 patients. 5 were managed surgically. There were no complications in the surgical or conservative management group including 2 patients who met the criteria for surgical Mx but in who surgery was contraindicated.	Use of CT rather than MRI which is thought to be less sensitive. - different form
Lee KH, Kim HM, Kim YS, et al. 2010 South Korea	Inclusion criteria - consecutive patients that had plain film demonstrating isolated GT# with suspected IT extension	Retrospective cohort	Proportion of patients with intertrochanteric extension and management	Intertrochanteric extension found in 20/25. 15 were managed surgically. There were no complications amongst those treated conservatively including 4 patients who met the criteria for surgical Mx but in who surgery was contraindicated.	Not stated whether study includes all patients with isolated GT fracture or only those requiring further imaging.
Feldman F, Staron RB 2004 United states	Consecutive patients that had plain film demonstrating isolated GT# and also had MRI	Retrospective cohort	Proportion of patients with intertrochanteric extension and management	Intertrochanter extension found in 35/37. 30 were managed surgically. There were no complications amongst those treated conservatively including 5 patients who met the criteria for surgical Mx but in who surgery was contraindicated.	Not stated whether study includes all patients with isolated GT fracture or only those requiring further imaging.
Learch, T., Pathria, M. 2000 United States	Consecutive patients that had plain film demonstrating isolated GT# or GT# with suspected IT ext	Retrospective cohort	Proportion of patients with intertrochanteric extension and management	Intertrochanter extension found in 8/8. 6 were managed surgically and 2 conservatively without complication in either group.	Only includes patients with suspected occult injury. Small sample size.
Craig JG, Moed BR, Eyler WR, van Holsbeeck M. 2000 United States	Consecutive patients that had plain film demonstrating isolated GT# and also had MRI	Retrospective cohort	Proportion of patients with intertrochanteric extension and management	Intertrochanter extension found in 10/13. 6 were managed surgically and 7 (including 4 with limited extension of the fracture) were treated conservatively with no complications in either group.	Small sample size. Not stated whether study includes all patients with isolated GT fracture or only those requiring further imaging. Extent of fracture extension not quantified.
Omura T, Takahashi M, Koide Y, et al 2000 Japan	Consecutive patients that had plain film demonstrating isolated GT# and seemed to have severer injury and had MRI	Retrospective cohort	Proportion of patients with intertrochanteric extension and management	Intertrochanter extension found in 7/8. All patients were managed conservatively without complication.	Small sample size. Patients with isolated GT fracture on plain film but did not require MRI were not included.

Comment(s)

Five more recent larger studies directly attempted to answer a similar question to our BET. The results are heavily polarised. The two most recent (Noh, Moon) showed that a large majority of patients (111/130 (85%)) were found to have intertrochanteric extension on MRI and 82/130 (63%) were surgically managed. In contrast three other recent papers (Park, Thurston, Wong) state that a minority (14/37, 15/85, 10/58 (22%)) patients showed intertrochanteric extension, and surgery performed in only 12/180 (7%) patients. Several earlier smaller studies attempt to answer the question but these are smaller with unclear selection criteria and there is a wide diversity of outcomes. Across all studies to a significant but varied proportion of patients are managed surgically for intertrochanteric extension without complication, but without strong evidence to guide the decision making. Of particular note to our BET, in those studies that recorded outcomes for all patients managed conservatively (272 of 434 patients) there was only one report of an adverse outcome (fracture displacement in a patient who declined surgery) (Park 2018).

Clinical Bottom Line

The evidence is weak and strongly polarised. UK research to date shows successful conservative management in 95% of isolated intertrochanteric fracture. Although MRI gives the greatest sensitivity in identifying occult fracture, little is known about the predictors of fracture completion and displacement in conservative management; the risk of which appears to be low but as yet unquantified.

References

1. Noh J, Lee KH, Jung S, Hwang S. The Frequency of Occult Intertrochanteric Fractures among Individuals with Isolated Greater Trochanteric Fractures.
2. Moon, N.H., Shin, W.C., Do, M.U. et al. Diagnostic strategy for elderly patients with isolated greater trochanter fractures on plain radiographs. BMC Musculoskelet Disord 19, 256 (2018)
3. Park JH, Shon HC, Chang JS, et al. How can MRI change the treatment strategy in apparently isolated greater trochanteric fracture? Injury 2018;49:824–828
4. Thurston D.; Marson B.; Ollivere B.; Westbrook T.; Moran C. et al. The management of isolated greater trochanter fractures: Is crosssectional imaging necessary? HIP International Sep 2018; vol. 28 ; p. 15-16
5. Chung PH, Kang S, Kim JP, et al Occult intertrochanteric fracture mimicking the fracture of greater trochanter Hip Pelvis 2016;28:112–119
6. Wong WY, Chu PY, Chan SWC, Yeung TW, Yuen MK Occult Intertrochanteric Extension in Isolated Greater Trochanteric Fracture on Plain Radiographs. Hong Kong Journal of Radiology 2016. 19. 28-34.
7. Kim SJ, Ahn J, Kim HK, Kim JH Is magnetic resonance imaging necessary in isolated greater trochanter fracture? A systemic review and pooled analysis BMC Musculoskeletal Disorders 2015 ;16:395
8. Reiter M, O’Brien SD, Bui-Mansfield LT, Alderete J. Greater trochanteric fracture with occult intertrochanteric extension Emerg Radiol 2013;20:469-72.
9. Suzuki K, Kawachi S, Nanke H Insufficiency femoral intertrochanteric fractures associated with greater trochanteric avulsion fractures Arch Orthop Trauma Surg 2011;131(12):1697–702
10. Lee KH, Kim HM, Kim YS, et al. Isolated fractures of the greater trochanter with occult intertrochanteric extension. Arch Orthop Trauma Surg 2010;130:1275–1280
11. Feldman F, Staron RB MRI of seemingly isolated greater trochanteric fractures. Am J Roentgenol 2004;183:323–329
12. Learch, T., Pathria, M. Greater trochanter fractures: MR assessment and its influence on patient management. Emergency Radiology 2000, 7, 89–92
13. Craig JG, Moed BR, Eyler WR, van Holsbeeck M. Fractures of the greater trochanter: intertrochanteric extension shown by MR imaging. Skeletal Radiol. 2000;29:572–576.
14. Omura T, Takahashi M, Koide Y, et al Evaluation of isolated fractures of the greater trochanter with magnetic resonance imaging Arch Orthop Trauma Surg 2000;120:195–197