GENERAL INFORMATION

It is an expectation that all patients receive care/services from a licensed clinician. All appropriate supporting documentation, including recent pertinent office visit notes, laboratory data, and results of any special testing must be provided. If applicable: All prior relevant imaging results and the reason that alternative imaging cannot be performed must be included in the documentation submitted.

Where a specific clinical indication is not directly addressed in this guideline, medical necessity determination will be made based on widely accepted standard of care criteria. These criteria are supported by evidence-based or peer-reviewed sources such as medical literature, societal guidelines and state/national recommendations.

Policy 
INDICATIONS FOR LOWER EXTREMITY MRI (FOOT, ANKLE, KNEE, LEG or HIP)
Pre-condition
Plain radiographs must precede MRI evaluation unless otherwise indicated.

Joint or Muscle Pain^1,2,3
Negative Findings on Orthopedic Exam and After X-Ray Completed

NOTE: Does not apply to young children (up to age 12)

• Persistent joint or musculotendinous pain unresponsive to conservative treatment*, within the last 6 months which includes active medical therapy (physical therapy, chiropractic treatments, and/or physician supervised exercise**) of at least four weeks
• With progression or worsening of symptoms during the course of conservative treatment

Joint Specific Provocative Exam Tests and Suspected Injuries⁴
Approvable Orthopedic Test
With a positive orthopedic sign, an initial x-ray is always preferred; however, it is not required to approve advanced imaging UNLESS otherwise specified in bold below. Any test that suggests joint instability requires further imaging (the below list is not all inclusive)

Ankle^5,6

• Syndesmotic injury (high ankle injury) with tenderness to palpation over the syndesmosis (anterior inferior tibiofibular ligament [AITFL]) and any of the following:^7,8
  • Positive stress X-rays
  • Squeeze test
  • Cotton test
  • Dorsiflexion external rotation test
• Unstable lateral injury to ATFL (anterior talofibular ligament) with suspicion of a possible associated fracture around the ankle or a possible osteochondral injury of the talus and any ONE of the following:⁹
  • Positive stress X-rays
  • Positive anterior drawer test with non-diagnostic or inconclusive X-rays
  • Positive posterior drawer test with non-diagnostic or inconclusive X-rays
• Achilles tendon tear¹⁰
  • Thompson test or palpable partial or complete Achilles defect on physical examination

Knee^11,12

• Lateral Collateral ligament tear
  • Positive Varus stress testing/laxity

Hip

• Femoroacetabular impingement (FAI)/Labral tear^18,19,20
  • Anterior Impingement sign (aka FADIR test) (Hip or groin pain with flexion, adduction, and internal rotation)
  • Posterior Impingement sign (Pain with hip extension and external rotation on exam)
  • Persistent hip mechanical symptoms (after initial radiographs completed) including clicking, locking, catching, giving way or hip instability with a clinical suspicion of labral tear and/or radiographic findings suggestive of FAI (i.e., cross over sign, pistol grip deformity, alpha angle over 50 degrees) and suspected labral tear
  • Determine candidacy for hip preservation surgery for known FAI

NOTE: For evaluation of both hips when the patient meets hip MRI guidelines (X-ray + persistent pain unresponsive to conservative treatment) for both the right and left hip, Evolent Clinical Guideline 037 for Pelvis MRI is the preferred study.

• Labral tear is suspected and fulfills above criteria, then bilateral hip MRIs are the preferred studies (not Pelvis MRI)
• Bilateral hip arthrograms are requested and otherwise meet guidelines, bilateral hip MRIs are the preferred studies (not Pelvis MRI)

Tendon Rupture^21,22
After X-Ray and Not Listed Above
High clinical suspicion of specific tendon rupture based on mechanism of injury and physical findings (i.e., palpable defect in quadriceps or patellar tendon rupture)

Trauma
Bone Fracture

• • Suspicion of a hip fracture in a pregnant patient does not require an initial X-ray
• Non-hip extremities: Suspected occult, stress, or insufficiency fracture²⁴
  • If X-rays, taken 10 – 14 days after the injury or clinical assessment, are negative or non-diagnostic
  • If at high risk for a complete fracture with conservative therapy (e.g., navicular bone), then immediate MRI is warranted.
• Pathologic or concern for impending fracture on x-ray or CT²⁴ — approve immediate MRI
• Suspected ligamentous/tendon injury with known fractures on X-ray/CT that may require surgery
• Nonunion or delayed union as demonstrated by no healing between two sets of X-rays. If a fracture has not healed by 4 – 6 months, there is delayed union. Incomplete healing by 6 – 8 months is nonunion, CT is the preferred study.²⁵

Osteochondral Lesions^12,26,27
Defects, Fractures, Osteochondritis Dissecans
Clinical suspicion based on mechanism of injury and physical findings
NOTE: X-ray completed

Joint Prosthesis/Replacement²⁸
Suspected joint prosthesis loosening, or dysfunction, (i.e., pseudotumor formation) after initial X-rays

• Suspected Metallosis with painful metal on metal hip replacement²⁹ after initial X- rays

Extremity Mass³⁰

Known Primary Cancer of the Extremity^32,33,34,35

• Initial staging primary extremity tumor
• Follow-up of known primary cancer of patient undergoing active treatment within the past year or as per surveillance imaging guidance for that cancer
• Signs or symptoms or imaging findings suspicious for recurrence
• Suspected metastatic disease with signs/symptoms and after initial imaging with radiographs

Further Evaluation of Indeterminate Findings on Prior Imaging
Unless follow-up is otherwise specified within the guideline:

• For initial evaluation of an inconclusive finding on a prior imaging report that requires further clarification
• One follow-up exam of a prior indeterminate MR/CT finding to ensure no suspicious interval change has occurred. (No further surveillance unless specified as highly suspicious or change was found on last follow-up exam.)

Osteonecrosis^36,37

• To further characterize a prior abnormal X-ray or CT suggesting osteonecrosis
• Normal or indeterminate X-rays, but symptomatic and high risk (such as glucocorticosteroid use, renal transplant, glycogen storage disease, alcohol abuse, sickle cell anemia)
• Known osteonecrosis to evaluate a contralateral joint after initial X-rays

e.g., Avascular Necrosis (AVN), Legg-Calve-Perthes Disease

Loose Bodies or Synovial Chondromatosis³⁸
(After X-Ray or Ultrasound Completed)
In the setting of joint pain or mechanical symptoms
 

Infection of Bone, Joint, or Soft Tissue Abscess³⁹

• Abnormal X-ray or ultrasound
• Negative X-ray or ultrasound but with a clinical suspicion of infection based on either of the following:
  • Signs and symptoms of joint or bone infection such as:
    • Pain and swelling
    • Decreased range of motion
    • Fevers
  • Laboratory findings of infection include any of the following:
    • Elevated ESR or CRP
    • Elevated white blood cell count
    • Positive joint aspiration

• Ulcer (diabetic, pressure, ischemic, traumatic) with signs of infection (redness, warmth, swelling, pain, discharge which may range from white to serosanguineous) that is not improving despite treatment and bone, or deep infection is suspected⁴⁰
  • Increased suspicion if size or temperature increases, bone is exposed/positive probe-to-bone test, new areas of breakdown, new smell
• Neuropathic foot with friable or discolored granulation tissue, foul odor, non-purulent discharge, and delayed wound healing⁴⁰

Pre-Operative/Procedural Evaluation
Pre-operative evaluation for a planned surgery or procedure

Evaluation of Tumor
When needed for clarification of vascular invasion from tumor after prior imaging.

Post-Operative/Procedural Evaluation

• When imaging, physical examination, or laboratory findings indicate joint infection, delayed or non-healing or other surgical/procedural complications.
• Trendelenburg sign⁽⁴¹⁾ or other indication of muscle or nerve damage after recent hip surgery

Evaluation of Known or Suspected Autoimmune Disease^42,43

• Further evaluation of an abnormality or non-diagnostic findings on prior imaging
• Initial imaging of a single joint for diagnosis or response to therapy after plain films and appropriate lab tests (e.g., RF, ANA, CRP, ESR)
• To determine change in treatment or when diagnosis is uncertain prior to start of treatment
• Follow-up to determine treatment efficacy of the following:
  • Early rheumatoid arthritis
  • Advanced rheumatoid arthritis if X-ray and ultrasound are equivocal or noncontributory

e.g., Rheumatoid Arthritis

Known or Suspected Inflammatory Myopathies⁴⁴

• For diagnosis
• For biopsy planning

NOTE: Includes polymyositis, dermatomyositis, immune-mediated necrotizing myopathy, inclusion body myositis

Peripheral Nerve Entrapment^45,46

• Abnormal electromyogram or nerve conduction study
• Abnormal X-ray or ultrasound
• Clinical suspicion and failed 4 weeks conservative treatment including at least two of the following (active treatment with physical therapy is not required):
  • Activity modification
  • Rest, ice, or heat
  • Splinting or orthotics
  • Medication

e.g., Tarsal tunnel, Morton’s neuroma

Foreign Body⁴⁷
Indeterminate X-ray and ultrasound
 

Painful Acquired or Congenital Flatfoot Deformity^48,49
Adult

• After X-ray completed
• After failure of active conservative therapy
  • Including at least two of the following (active treatment with physical therapy is not required):
    • Activity modification
    • Rest, ice, or heat
    • Splinting or orthotics
    • Medication

Pediatrics (Up to Age 18)

• Painful flatfoot (pes planus) deformity with suspected tarsal coalition, not responsive to non-active conservative care (such as orthotics, rest etc.)⁵⁰
• Slipped Capital Femoral Epiphysis with negative frog leg and AP x-rays of the hips but clinically suspected^51,52
  • Drehmann sign
  • Limited internal rotation of the hip
  • Consider imaging the asymptomatic contralateral hip with a normal x-ray to detect early SCFE if prophylactic surgery is planned
• Chronic Recurrent Multifocal Osteomyelitis after initial work-up (labs (i.e. CRP/ESR and X-ray)^53,54
  • Whole body bone marrow MRI is more appropriate when multiple joints requested; see Evolent_CG_059 for Bone Marrow MRI.
• Acute limp in a child 5 or less years old⁵⁵
  • Concern for infection not localized to the hip (initial imaging not required)
  • Concern for infection localized to the hip after initial evaluation with ultrasound
• Osteoid Osteoma — MRI not usually done because X-ray and CT more accurate for diagnosis⁵⁶

Rationale
MRI
Magnetic resonance imaging shows the soft tissues and bones. With its multiplanar capabilities, high contrast, and high spatial resolution, it is an accurate diagnostic tool for conditions affecting the joint and adjacent structures.

MRI can positively influence clinicians’ diagnoses and management plans for patients with conditions such as primary bone cancer, fractures, abnormalities in ligaments/tendons/cartilage, septic arthritis, and infection/inflammation.

Special Note

• Plain radiographs must precede MRI evaluation unless otherwise indicated.
• Some indications are for MRI, CT, or MR or CT Arthrogram (more than one should not be approved at the same time).
• If an MR Arthrogram fits approvable criteria below, approve as MRI.

OVERVIEW
*Conservative Therapy
Musculoskeletal should include a multimodality approach consisting of a combination of active and inactive components.

Inactive components such as rest, ice, heat, modified activities, medical devices, (including crutches, immobilizer, metal braces, orthotics, rigid stabilizer, or splints, etc. and not to include neoprene sleeves), medications, injections (bursal, and/or joint, not including trigger point), and diathermy, can be utilized.

Active modalities may consist of physical therapy, a physician supervised home exercise program,** and/or chiropractic care.

**Home exercise program (HEP) 
The following two elements are required to meet guidelines for completion of conservative therapy:

• Information provided on exercise prescription/plan AND
• Follow-up with member with information provided regarding completion of HEP (after suitable 4-week period), or inability to complete HEP due to physical reason- i.e., increased pain, inability to physically perform exercises.

NOTE: Patient inconvenience or noncompliance without explanation does not constitute
“inability to complete” HEP

Contraindication and Preferred Studies

• Contraindications and reasons why a CT/CTA cannot be performed may include impaired renal function, significant allergy to IV contrast, pregnancy (depending on trimester).
• Contraindications and reasons why an MRI/MRA cannot be performed may include impaired renal function, claustrophobia, non-MRI compatible devices (such as non-compatible defibrillator or pacemaker), metallic fragments in a high-risk location, patient exceeds weight limit/dimensions of MRI machine.

References

50. Raj M, Tafti D, Kiel J. Pes Planus. [Updated 2023 May 23]. StatPearls Publishing. 2023; https://www.ncbi.nlm.nih.gov/books/NBK430802/.
51. Aprato A, Conti A, Bertolo F, Massè A. Slipped capital femoral epiphysis: current management strategies. Orthopedic research and reviews. 2019; 11: 47-54. 10.2147/ORR.S166735. eCollection 2019.
52. Johns K, Mabrouk A, Tavarez M. Slipped Capital Femoral Epiphysis. [Updated 2023 Jul 25]. StatPearls Publishing. 2023; https://www.ncbi.nlm.nih.gov/books/NBK538302/.
53. Roderick M, Shah R, Rogers V, Finn A, Ramanan A. Chronic recurrent multifocal osteomyelitis (CRMO) - advancing the diagnosis. Pediatr Rheumatol Online J. Aug 30, 2016; 14: 47. 10.1186/s12969-016-0109-1.
54. Zhao D, McCann L, Hahn G, Hedrich C. Chronic nonbacterial osteomyelitis (CNO) and chronic recurrent multifocal osteomyelitis (CRMO). J Transl Autoimmun. 2021; 4: 100095. 10.1016/j.jtauto.2021.100095.
55. Safdar N M, Rigsby C K, Iyer R S, Alazraki A L, Anupindi S A et al. ACR Appropriateness Criteria(®) Acutely Limping Child Up to Age 5. J Am Coll Radiol. 2018; 15: S252-s262. 10.1016/j.jacr.2018.09.030.
56. Iyer R, Chapman T, Chew F. Pediatric bone imaging: diagnostic imaging of osteoid osteoma. AJR Am J Roentgenol. May 2012; 198: 1039-52. 10.2214/ajr.10.7313.

Coding Section 

Codes	Number	Description
CPT	73718	Magnetic resonance (e.g., proton) imaging, lower extremity other than joint; without contrast material(s)
	73719	with contrast material(s)
	73720	without contrast material(s), followed by contrast material(s) and further sequences
	73721	Magnetic resonance (e.g., proton) imaging, any joint of lower extremity; without contrast material
	73722	with contrast material(s)
	73723	without contrast material(s), followed by contrast material(s) and further sequences
	0698T	Quantitative magnetic resonance for analysis of tissue composition (eg, fat, iron, water content), including multiparametric data acquisition, data preparation and transmission, interpretation and report, multiple organs

Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive. 

This medical policy was developed through consideration of peer-reviewed medical literature generally recognized by the relevant medical community, U.S. FDA approval status, nationally accepted standards of medical practice and accepted standards of medical practice in this community, and other nonaffiliated technology evaluation centers, reference to federal regulations, other plan medical policies, and accredited national guidelines.

"Current Procedural Terminology © American Medical Association. All Rights Reserved" 

History From 2019 Forward 

12/05/2024	Annual review, no change to policy intent but policy reformatted for clarity and consistency. Removing verbiage regarding sonogram for leg length. Adding special note , Contraindication/preferred  for clarity and consistency. Updating references
12/04/2023	Annual review, updating entire policy for clarity. Adding verbiage regarding orthopedic signs updated, clarifying hip vs pelvis imaging, indeterminate findings metallosis, and indications not addressed in the policy.
12/06/2022	Annual review, no change to policy intent. Policy updated for specificity and clarity.
12/06/2021	Annual review, adding policy verbiage related to unstable syndesmotic injury, navicular bone to hgh risk stress fracture, suspected bone infection in the setting of ulcers and neuropathy, following treatment for rheumatoid arthritis, clarifying pre and post operative statements. Also updating description and references.
12/01/2020	Annual review, added policy verbiage for pediatrics, loose bodies, delayed union, flatfoot, labral tear and joint implants/hardware. Also updating description and references.
12/17/2019	NEW POLICY