Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis

Department of Orthopaedic Surgery and Rehabilitation

Srikanth Divi, MD Cody Lee, BS Douglas Dirschl, MD Kelly Hynes, MD

Disclosure

NO CONFLICTS TO DISCLOSE Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis

Srikanth Divi, MD

Cody Lee, BS

Douglas Dirschl, MD

Kelly Hynes, MD

Our disclosures are in the Final AOFAS Mobile App.

We have no potential conflicts with this presentation.

2 Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis |

Introduction

•  Osteomyelitis (OM) of the foot and ankle is a common condition with a high economic burden, especially in the context of diabetes mellitus

•  Timely and accurate diagnosis of OM is important for treatment initiation and for the reduction of healthcare costs

•  MRI is considered the most sensitive imaging modality for OM of the foot and ankle, but is associated with significant cost and variable treatment impact when compared to plain radiographs

3 Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis |

Objectives

•  The purpose of this study is to determine:

1)  the proportion of patients with a diagnosis of osteomyelitis that underwent an MRI 2)  the rate of operative procedures in the MRI cohort and non-MRI (NMRI) cohort 3)  the proportion of MRIs that changed clinical treatment leading to an operative

procedure (impact study) 4)  the effective cost of MRI for osteomyelitis of the foot and ankle

4 Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis |

Materials and Methods •  Patients were retrospectively identified at a single tertiary care, academic medical

center and included if:

•  treated between January 2009 and September 2015 •  diagnosed with OM using ICD-9 codes 730.07, 730.17, 730.27 (acute, chronic, and

unspecified osteomyelitis of the foot and ankle)

•  Demographic data, patient comorbidities, use of imaging, and any operative procedures were identified

•  Impact MRI was defined as MRI that led to an operative procedure within the same admission encounter

•  Cost of impact MRI was estimated using the following equation:

•  Student’s t-test and Chi-squared test were used to statistically compare the MRI and NMRI cohorts

•  Exclusion criteria: 1) patients <18 years old; 2) patients with <2 weeks of follow-up

5 Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis |

Cost $( ) = average MRI cost $( )× total MRIsimpact MRIs

"

#$

%

&'

Results

•  Patient flowchart

6 Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis |

543 pts

+ MRIs (144 pts) 220 MRIs

- MRIs (399 pts)

+ procedures (102 pts)

- procedures (42 pts) + procedures

(281 pts) - procedures

(118 pts)

83 impact MRIs

137 non-impact MRIs

Results

•  No statistically significant differences between the two cohorts with regards to age, sex, race or ethnicity

•  No significant difference in operative rates between the two cohorts (MRI=70.8% vs. NMRI=70.4%, p=0.93)

•  MRI cohort had greater mean Charlson Comorbidity Index value (MRI=3.4±2.2 vs. NMRI=2.7±2.1, p<0.05) and longer mean follow-up time (MRI=98.7±82.1 vs. NMRI=74.9±68.8, p<0.05)

7 Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis |

Results

•  Types of procedures performed between groups were different (Chi-squared, p<0.05)

•  NMRI group had slightly higher amputation rates (amputation through foot, ankle disarticulation, BKA, and AKA)

8 Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis |

Results

•  83 of 220 (37.7%) MRIs were impactful

•  Significant increasing trend identified for total MRIs ordered over time (p=0.012), as well as for impact MRIs (p=0.020)

•  The proportion of impact MRIs to total MRIs remained similar year-to-year (p=0.43)

9 Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis |

0  

10  

20  

30  

40  

50  

60  

70  

2009   2010   2011   2012   2013   2014   2015  

#  MRIs  p

erform

ed  

Year  

MRIs  over  1me  

Impact  MRIs  

Non-­‐impact  MRIs  

Results

•  Average MRI cost increased significantly (p=0.037)

•  No significant trend found for effective MRI cost (p=0.950)

10 Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis |

0  

2000  

4000  

6000  

8000  

10000  

12000  

14000  

16000  

18000  

20000  

2009   2010   2011   2012   2013   2014   2015  

Cost  of  M

RI  ($

)  

Year  

Effec1ve  Cost  of  MRI  over  Time  

Avg  MRI  Cost  

EffecAve  Cost  MRI  

Conclusions

•  144 out of 543 patients diagnosed with osteomyelitis of the foot and ankle underwent MRI

•  No significant difference found in operative rate between MRI and non-MRI cohorts

•  83 out of 220 performed MRIs were impactful

•  Effective cost of impact MRI ranged from $8,568.00 to $18,853.30, roughly 2 to 5 times the average MRI cost

•  This study suggests that the use of MRI adds cost while not necessarily changing treatment in patients diagnosed with foot and ankle osteomyelitis

11 Financial Impact of MRI in the Treatment of Foot and Ankle Osteomyelitis |

References 1.  Nelson EA, O'Meara S, Craig D, Iglesias C, Golder S, Dalton J, et al. A series of systematic reviews to inform a decision analysis for sampling and treating

infected diabetic foot ulcers. Health Technology Assessment. 2006;10(12).

2.  Markanday A. Diagnosing Diabetic Foot Osteomyelitis: Narrative Review and a Suggested 2-Step Score-Based Diagnostic Pathway for Clinicians. Open Forum Infectious Diseases. 2014;1(2).

3.  Dinh MT, Abad CL, Safdar N. Diagnostic Accuracy of the Physical Examination and Imaging Tests for Osteomyelitis Underlying Diabetic Foot Ulcers: Meta-Analysis. Clinical Infectious Diseases. 2008;47(4):519–27.

4.  Lipsky BA, Berendt AR, Cornia PB, Pile JC, Peters EJG, Armstrong DG, et al. Executive Summary: 2012 Infectious Diseases Society of America Clinical Practice Guideline for the Diagnosis and Treatment of Diabetic Foot Infections. Clinical Infectious Diseases. 2012;54(12):1679–84.

5.  Eckman MH, Greenfield S, Mackey WC, Wong JB, Kaplan S, Sullivan L, et al. Foot infections in diabetic patients: decision and cost-effectiveness analyses. JAMA. 1995;273(9):712–20.

6.  Larson DL, Gilstrap J, Simonelic K, Carrera GF. Is There a Simple, Definitive, and Cost-Effective Way to Diagnose Osteomyelitis in the Pressure Ulcer Patient? Plastic and Reconstructive Surgery. 2011;127(2):670–6.

7.  Keeney JA, Nunley RM, Adelani M, Mall N. Magnetic Resonance Imaging of the Hip: Poor Cost Utility for Treatment of Adult Patients With Hip Pain. Clinical Orthopaedics and Related Research. 2014;472(3):787–92.

8.  Chow I, Lemos EV, Einarson TR. Management and Prevention of Diabetic Foot Ulcers and Infections. Pharmacoeconomics. 2008;26(12):1019–35.

9.  Morrison WB, Schweitzer ME, Wapner KL, Hecht PJ, Gannon FH, Behm WR. Osteomyelitis in feet of diabetics: clinical accuracy, surgical utility, and cost-effectiveness of MR imaging. Radiology. 1995;196(2):557–64.

10.  Game FL. Osteomyelitis in the Diabetic Foot. Medical Clinics of North America. 2013;97(5):947–56.

11.  Dinh T, Snyder G, Veves A. Review Papers: Current Techniques to Detect Foot Infection in the Diabetic Patient. The International Journal of Lower Extremity Wounds. 2010;9(1):24–30.

12.  Donovan A, Schweitzer ME. Use of MR Imaging in Diagnosing Diabetes-related Pedal Osteomyelitis. RadioGraphics. 2010;30(3):723–36.

13.  Morales Lozano R, Gonzalez Fernandez ML, Martinez Hernandez D, Beneit Montesinos JV, Guisado Jimenez S, Gonzalez Jurado MA. Validating the Probe-to-Bone Test and Other Tests for Diagnosing Chronic Osteomyelitis in the Diabetic Foot. Diabetes Care. 2010;33(10):2140–5.

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