Louisiana Administrative Code › Title 40 - LABOR AND EMPLOYMENT › Part I - Workers' Compensation Administration › Subpart 2 - Medical Guidelines › Chapter 23 - Upper and Lower Extremities Medical Treatment Guidelines › Subchapter B - Shoulder Injury Medical Treatment Guidelines › Section I-2321 - Follow-Up Diagnostic Imaging and Testing Procedures

Current through Register Vol. 50, No. 6, June 20, 2024
A. One diagnostic imaging procedure may
					 provide the same or distinctive information as does another procedure.
					 Therefore, the prudent choice of a single diagnostic procedure, a complement of
					 procedures or a sequence of procedures will optimize diagnostic accuracy;
					 maximize cost effectiveness (by avoiding redundancy), and minimize potential
					 adverse effects to patients.
B. All
					 diagnostic imaging procedures have a significant percentage of specificity and
					 sensitivity for various diagnoses. None is specifically characteristic of a
					 certain diagnosis. Clinical information obtained by history taking and physical
					 examination should form the basis for selecting an imaging procedure and
					 interpreting its results.
C. When a
					 diagnostic procedure, in conjunction with clinical information, can provide
					 sufficient information to establish an accurate diagnosis, the second
					 diagnostic procedure will become a redundant procedure. At the same time, a
					 subsequent diagnostic procedure can be a complementary diagnostic procedure if
					 the first or preceding procedures, in conjunction with clinical information,
					 cannot provide an accurate diagnosis. Usually, preference of a procedure over
					 others depends upon availability, a patient's tolerance, and/or the treating
					 practitioner's familiarity with the procedure.
1. Imaging Studies are generally accepted,
					 well-established and widely used diagnostic procedures. When indicated, the
					 following additional imaging studies can be utilized for further evaluation of
					 the shoulder, based upon the mechanism of injury, symptoms, and patient
					 history. For specific clinical indications, refer to Specific Diagnosis,
					 Testing and Treatment Procedures. The studies below are listed by frequency of
					 use, not importance. Diagnostic imaging may be useful in resolving the
					 diagnostic uncertainties that remain after the clinical examination. Even a
					 thorough history and physical examination may not define the shoulder pathology
					 that produces the patient's symptoms. Therefore, additional investigations
					 should be considered as an accepted part of the patient evaluation when surgery
					 is being considered or clarification of diagnosis is necessary to formulate a
					 treatment plan.
a. X-ray is widely accepted
					 and frequently the first imaging study performed. Three radiographically
					 distinguishable acromion types have been described: Type I (flat), Type II
					 (curved), and Type III (hooked). Historically, acromion type was correlated
					 with incidence of rotator cuff pathologies and with outcome of nonsurgical
					 treatment of shoulder pain. However, there is considerable variation between
					 observers regarding the acromial types, both in interpreting plain x-rays and
					 in classifying anatomical specimens. Acromial morphology should not be used to
					 assess the likelihood of rotator cuff pathology. Acromial morphology alone
					 should not be considered an indication for acromioplasty, as up to 40 percent
					 of asymptomatic adults may have a Type II acromion. Appropriate soft tissue
					 imaging techniques such as sonography and MRI should be used to assess rotator
					 cuff or bursa status.
b. Diagnostic
					 Sonography is an accepted technique for suspected full-thickness tears. A
					 positive sonogram has a high specificity of 96 percent and provides convincing
					 confirmation of the diagnosis. Sensitivity is high, 87 percent, however,
					 negative sonography does not rule out a full-thickness tear. For partial
					 thickness tears, a positive sonogram has high specificity, 94 percent, but is
					 only moderately sensitive, 67 percent. A negative sonogram does not exclude the
					 diagnosis of a partial thickness tear. The performance of sonography is
					 operator-dependent, and is best when done by a specialist in musculoskeletal
					 radiology. It is preferable to MRI when the patient is claustrophobic or has
					 inserted medical devices.
c.
					 Magnetic Resonance Imaging (MRI) is generally accepted and widely used to
					 provide a more definitive visualization of soft tissue structures, including
					 ligaments, tendons, joint capsule, and joint cartilage structures, than x-ray
					 or Computed Axial Tomography (CT) in the evaluation of traumatic or
					 degenerative injuries. The addition of intravenous or intra-articular contrast
					 can enhance definition of selected pathologies. In general, the high field,
					 conventional, MRI provides better resolution than a low field scan. A lower
					 field scan may be indicated when a patient cannot fit into a high field scanner
					 or is too claustrophobic despite sedation. Inadequate resolution on the first
					 scan may require a second MRI using a different technique. All questions in
					 this regard should be discussed with the MRI center and/or radiologist. MRI
					 provides excellent soft tissue detail, but interpretation of the image is
					 problematic and depends on operator skill. A positive MRI has high specificity
					 of 93 percent and provides supporting evidence that a clinical suspicion of a
					 full-thickness tear is correct. Sensitivity of MRI for full-thickness tears is
					 also high at 89 percent. However, it may not identify the pathology in some
					 cases. For partial thickness tears, sensitivity of MRI is below 50 percent but
					 its specificity is high at 90 percent.
d. Computed Axial Tomography (CT): is
					 generally accepted and provides excellent visualization of bone and is used to
					 further evaluate bony masses and suspected fractures not clearly identified on
					 radiographic window evaluation. Instrument scatter-reduction software provides
					 better resolution when metallic artifact is of concern.
e. MR Arthrography (MRA): This accepted
					 investigation uses the paramagnetic properties of gadolinium to shorten T1
					 relaxation times and provide a more intense MRI signal. It can accurately
					 demonstrate and rule out full-thickness tears as well as non-contrast MRI, but
					 it is invasive and its place in the evaluation of rotator cuff pathology has
					 not been determined. In select populations of highly active athletes, it may
					 uncover unsuspected labral pathology such as SLAP lesions, but the
					 arthroscopically normal labrum may produce an abnormal signal in half of MRA
					 studies. Its contribution to the diagnosis of SLAP lesions has not been
					 determined. An MRA is not necessary if the patient has already met indications
					 for arthroscopy or surgery as outlined in Specific Diagnosis, Testing and
					 Treatment. However, an MRA may be ordered when the surgeon desires further
					 information prior to surgery.
f.
					 Venogram/Arteriogram is a generally accepted test is useful for investigation
					 of vascular injuries or disease, including deep-venous thrombosis. Potential
					 complications may include pain, allergic reaction, and deep-vein
					 thrombosis.
g. Bone Scan
					 (Radioisotope Bone Scanning): is generally accepted, well-established and
					 widely used. Bone scanning is more sensitive but less specific than MRI.
					 99MTechnecium diphosphonate uptake reflects osteoblastic activity and may be
					 useful in metastatic/primary bone tumors, stress fractures, osteomyelitis, and
					 inflammatory lesions, but cannot distinguish between these entities. Bone
					 scanning is more sensitive but less specific than MRI. It is useful for the
					 investigation of trauma, infection, stress fracture, occult fracture, Complex
					 Regional Pain Syndrome, and suspected neoplastic conditions of the upper
					 extremity.
h. Other Radioisotope
					 Scanning Indium and gallium scans are generally accepted procedures usually to
					 help diagnose lesions seen on other diagnostic imaging studies. 67Gallium
					 citrate scans are used to localize tumor, infection, and abscesses.
					 111Indium-labeled leukocyte scanning is utilized for localization of infection
					 or inflammation.
i. Arthrograms are
					 accepted; however, rarely used except for evaluation of patients with metal
					 implants and previous shoulder surgery.
j. If the patient has a positive ultrasound,
					 MRI, or Arthrogram - only one of these tests are necessary to diagnose a
					 rotator cuff tear. Any additional tests must be for additional
					 diagnosis.
k. Diagnostic Arthroscopy
					 (DA) allows direct visualization of the interior of a joint, enabling the
					 diagnosis of conditions when other diagnostic tests have failed to reveal an
					 accurate diagnosis; however, it should generally not be employed for
					 exploration purposes only. In order to perform a diagnostic arthroscopy, the
					 patient must have completed at least some conservative therapy without
					 sufficient functional recovery and meet criteria for arthroscopic repair.
i. DA may also be employed in the treatment
					 of acute joint disorders. In some cases, the mechanism of injury and physical
					 examination findings will strongly suggest the presence of a surgical lesion.
					 In those cases, it is appropriate to proceed directly with the interventional
					 arthroscopy.