{"id":171327,"date":"2026-08-04T07:04:15","date_gmt":"2026-08-04T07:04:15","guid":{"rendered":"https:\/\/pabau.com\/?p=171327"},"modified":"2026-08-17T12:29:31","modified_gmt":"2026-08-17T12:29:31","slug":"icd-10-code-m453","status":"publish","type":"post","link":"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/","title":{"rendered":"ICD-10 Code M45.3: Ankylosing spondylitis of the cervicothoracic region"},"content":{"rendered":"\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"MedicalWebPage\",\"headline\":\"ICD-10 Code M45.3: Ankylosing spondylitis of the cervicothoracic region\",\"description\":\"ICD-10 Code M45.3 describes ankylosing spondylitis (AS) of the cervicothoracic region. Learn billable status, documentation requirements, subcodes, and common coding errors.\",\"url\":\"https:\/\/pabau.com\/diagnostic-codes\/icd-10-code-m453\/\",\"audience\":{\"@type\":\"MedicalAudience\",\"audienceType\":\"Clinician\"},\"reviewedBy\":{\"@type\":\"Person\",\"name\":\"Dr Vanja Kitanova\",\"jobTitle\":\"Medical Reviewer\",\"affiliation\":{\"@type\":\"Organization\",\"name\":\"Pabau\"},\"knowsAbout\":[\"Medical Coding\",\"Clinical Documentation\",\"Healthcare Billing\",\"Clinical Safety\"],\"sameAs\":\"https:\/\/pabau.com\/blog\/author\/vanja\/\"},\"datePublished\":\"2026-08-04\",\"dateModified\":\"2026-08-04\"}<\/script>\n\n\n        <div id=\"key_takeaways\">\n            <div class=\"header\">\n                                    <img decoding=\"async\" src=\"https:\/\/pabau.com\/wp-content\/uploads\/2025\/12\/Key-Takeaways-Icon.svg\" alt=\"Key takeaways\" height=\"42\" width=\"42\">\n                                <h3>Key takeaways<\/h3>\n            <\/div>\n            <div class=\"list\">\n                                                            <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#3D3D46\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p>ICD-10 Code M45.3 is a billable ICD-10-CM code for ankylosing spondylitis of the cervicothoracic region, valid for FY2026.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#3D3D46\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p>M45.3 carries an adult diagnosis restriction. It applies to patients aged 15 years and older, so pediatric use needs a documented clinical exception.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#3D3D46\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p>The most common error is defaulting to M45.9 when the notes already name the cervicothoracic region. Code to the highest specificity the chart supports.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#3D3D46\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p>Coding accuracy starts in the chart. Practice management software like Pabau keeps code selection and clinical documentation in one workflow.<\/p>\n                        <\/div>\n                                                <\/div>\n        <\/div>\n    \n\n\n<h2 class=\"wp-block-heading\">ICD-10 Code M45.3: Definition and billable status<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>ICD-10 Code M45.3<\/strong> is a billable, specific ICD-10-CM diagnosis code. Its official descriptor is <em>Ankylosing spondylitis of cervicothoracic region<\/em>, the C7-T1 junction. The code carries an adult diagnosis restriction, so it applies to patients aged 15 years and older.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It took effect on October 1, 2025 under the <a href=\"https:\/\/icd10cmtool.cdc.gov\/\" target=\"_blank\" rel=\"nofollow noopener\">CDC\/NCHS ICD-10-CM FY2026 edition<\/a> and stays valid through September 30, 2026. M45.3 is undercoded more often than it is miscoded. Coders reach for M45.9 even when imaging and physician notes name the affected region.<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\">\n<div class=\"wp-block-embed__wrapper\">\n<iframe title=\"ICD-10 Revisions: Stay Updated or Fall Behind\" width=\"800\" height=\"450\" src=\"https:\/\/www.youtube.com\/embed\/bqAyb-BCA0w?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div>\n<\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Ankylosing spondylitis and the cervicothoracic region<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Ankylosing spondylitis (AS) is a chronic inflammatory arthritis that targets the sacroiliac joints and axial skeleton. It sits in the spondyloarthropathy family alongside psoriatic arthritis, reactive arthritis, and arthritis linked to inflammatory bowel disease. Inflammation drives progressive fibrosis and eventual bony fusion, or ankylosis, of the affected spinal segments.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The <strong>cervicothoracic region<\/strong> is the junction between the cervical and thoracic spine, centered on the C7-T1 segments. AS involvement here produces a distinctive picture. Rheumatology teams and chiropractic practices see neck stiffness, restricted cervical rotation, and pain radiating into the arms.<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><strong>Onset:<\/strong> Typically insidious, beginning in early adulthood (teens to 30s)<\/li><li><strong>Primary joints involved:<\/strong> Sacroiliac joints, followed by the lumbar, thoracic, and cervical spine in ascending order<\/li><li><strong>Cervicothoracic AS findings:<\/strong> Reduced neck flexion, morning stiffness lasting more than 60 minutes, Schober&rsquo;s test restriction, elevated ESR\/CRP<\/li><li><strong>Imaging:<\/strong> MRI or plain radiograph showing erosions, sclerosis, or syndesmophytes at C7-T1<\/li><li><strong>Biomarker:<\/strong> HLA-B27 positivity in about 90% of AS cases<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Because AS climbs the spine, cervicothoracic involvement usually appears in patients with established lumbar or thoracic disease. Expect concurrent M45 subcodes such as <a href=\"https:\/\/pabau.com\/diagnostic-codes\/icd-10-code-m456\/\">M45.6<\/a> when you code an advanced presentation.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">M45.3 within the M45 ICD-10-CM code hierarchy<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">M45 is the parent category for ankylosing spondylitis under ICD-10-CM Chapter 13, which covers the musculoskeletal system and connective tissue. The category is not billable on its own. Every claim needs a specific subcode naming the anatomical region.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The <a href=\"https:\/\/www.aapc.com\/codes\/icd-10-codes-range\/\" target=\"_blank\" rel=\"nofollow noopener\">AAPC Codify ICD-10-CM lookup<\/a> lists ten ankylosing spondylitis subcodes, from the occipito-atlanto-axial region through to unspecified. The FY2026 tabular list also nests a separate M45.A block under M45. Those codes cover non-radiographic axial spondyloarthritis, a related but distinct diagnosis.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The table below maps those ten subcodes. Knowing where M45.3 sits helps you choose correctly when notes name more than one region. It also separates M45.3 from M45.2 above it and from the frequently misused M45.9 below.<\/p>\n\n\n\n<table style=\"width:100%;border-collapse:separate;border-spacing:0;border-radius:12px;overflow:hidden;font-size:15px;line-height:1.5;margin:1.5em 0 2em;box-shadow:0 2px 12px rgba(0,0,0,0.08)\">\n<thead>\n<tr>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4;min-width:120px\">Code<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Descriptor<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Notes<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M45.0<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Ankylosing spondylitis of multiple sites in spine<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Use when AS affects 2 or more spinal regions<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M45.1<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Ankylosing spondylitis of occipito-atlanto-axial region<\/td>\n<td style=\"padding:12px 16px;color:#374151\">C0-C2, the uppermost cervical segment<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M45.2<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Ankylosing spondylitis of cervical region<\/td>\n<td style=\"padding:12px 16px;color:#374151\">C3-C6<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\"><strong>M45.3<\/strong><\/td>\n<td style=\"padding:12px 16px;color:#374151\"><strong>Ankylosing spondylitis of cervicothoracic region<\/strong><\/td>\n<td style=\"padding:12px 16px;color:#374151\"><strong>C7-T1 junction, the primary code in this article<\/strong><\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M45.4<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Ankylosing spondylitis of thoracic region<\/td>\n<td style=\"padding:12px 16px;color:#374151\">T2-T11<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M45.5<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Ankylosing spondylitis of thoracolumbar region<\/td>\n<td style=\"padding:12px 16px;color:#374151\">T12-L1 junction<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M45.6<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Ankylosing spondylitis of lumbar region<\/td>\n<td style=\"padding:12px 16px;color:#374151\">L2-L4<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M45.7<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Ankylosing spondylitis of lumbosacral region<\/td>\n<td style=\"padding:12px 16px;color:#374151\">L5-S1<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M45.8<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Ankylosing spondylitis of sacral and sacrococcygeal region<\/td>\n<td style=\"padding:12px 16px;color:#374151\">S1-S5\/coccyx<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M45.9<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Ankylosing spondylitis of unspecified sites in spine<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Use only when the region cannot be specified from available documentation<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<h3 class=\"wp-block-heading\">Approximate synonyms for M45.3<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The following terms are clinically accepted synonyms and alternate descriptions coders may encounter in physician notes for M45.3:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Ankylosing spondylitis, cervicothoracic region<\/li><li>Cervicothoracic ankylosing spondylitis<\/li><li>AS of the C7-T1 junction<\/li><li>Inflammatory spondylitis, cervicothoracic<\/li><li>Cervicothoracic spondylitis NOS (when confirmed as ankylosing in origin)<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Most musculoskeletal diagnoses lead to therapy, charted in a <a href=\"https:\/\/pabau.com\/industry\/physical-therapy-emr\/\">physical therapy EMR<\/a> from first assessment to discharge.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Documentation requirements for ICD-10 Code M45.3<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Accurate use of ICD-10 Code M45.3 depends on what the chart already says before the encounter is coded. Missing one element below can trigger a payer query or a denial. Capturing them at the point of care.<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><strong>Anatomical region specification:<\/strong> The physician&rsquo;s note must explicitly name the cervicothoracic region or the C7-T1 vertebral segment. \u00ab\u00a0Upper spine\u00a0\u00bb or \u00ab\u00a0neck\u00a0\u00bb alone is insufficient.<\/li><li><strong>Confirmed AS diagnosis:<\/strong> Documentation must confirm ankylosing spondylitis, not just inflammatory back pain or spondylitis NOS. The working diagnosis must appear in the assessment section.<\/li><li><strong>Imaging results:<\/strong> Plain radiograph or MRI findings showing erosions, sclerosis, sacroiliitis, or syndesmophytes at the cervicothoracic level support the diagnosis. Imaging report reference or date must appear in the chart.<\/li><li><strong>HLA-B27 status:<\/strong> Per the <a href=\"https:\/\/www.cms.gov\/medicare\/coding-billing\/icd-10-codes\" target=\"_blank\" rel=\"nofollow noopener\">CMS ICD-10-CM coding guidance<\/a>, laboratory values used in the diagnosis should be documented. HLA-B27 positivity supports AS, but it does not confirm the diagnosis on its own. Clinical and imaging criteria must be met too.<\/li><li><strong>Clinical findings:<\/strong> Documentation of inflammatory back pain characteristics (morning stiffness exceeding 60 minutes, improvement with exercise, nocturnal worsening) strengthens medical necessity.<\/li><li><strong>Age of patient:<\/strong> M45.3 carries an adult diagnosis restriction, so the patient must be 15 years or older. For a patient under 15, document the clinical exception and check with the treating physician before coding.<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Region of involvement, the inflammatory symptom checklist, and the imaging reference all arrive filled in. The chart is complete before the coder opens it.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/cdn.pabau.com\/cdn\/attachments\/pulse\/content-engine\/diagnostic_codes\/icd-10-code-m453\/customizable-consent-and-intake-forms.webp\" alt=\"Customizable consent and intake forms in Pabau\"\/><figcaption class=\"wp-element-caption\"><em>Pabau&rsquo;s customizable intake forms capture the spinal region and inflammatory symptoms before anyone opens the chart to code it.<\/em><\/figcaption><\/figure>\n\n\n\n<div style=\"height:35px;width:800px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n        <div id=\"pro_tip\">\n            <div class=\"img\">\n                <svg width=\"42\" height=\"42\" viewBox=\"0 0 42 42\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                    <path fill-rule=\"evenodd\" clip-rule=\"evenodd\"\n                        d=\"M12.6383 19.5238C12.6632 21.2071 12.8734 22.9926 12.0685 24.5523C11.0341 26.8917 8.45076 28.169 7.56292 30.5918C6.63082 33.1061 7.19505 36.185 9.31371 37.9786C10.929 39.5678 13.4183 39.9873 15.6061 39.5463C17.4592 39.073 19.1049 37.8388 19.9706 36.1608C20.781 34.7141 20.7866 32.9904 20.5293 31.3985C20.1006 29.3092 18.3775 27.8705 16.9807 26.362C14.8814 24.1005 14.6684 20.6854 15.595 17.8915C16.4331 15.4768 19.0026 14.2344 20.0425 11.9461C20.7202 10.6769 20.7506 9.20327 20.6068 7.81304C20.1864 5.40098 18.3139 3.23631 15.8716 2.56674C13.9742 2.03969 11.8224 2.30052 10.1739 3.37614C8.70522 4.34688 7.5878 5.86618 7.28356 7.58178C6.76081 9.82981 7.53525 12.2822 9.20307 13.9118C10.7658 15.4741 12.4806 17.2273 12.6383 19.5238Z\"\n                        fill=\"#2BADD4\" \/>\n                    <path fill-rule=\"evenodd\" clip-rule=\"evenodd\"\n                        d=\"M22.7048 19.8387C22.6822 22.3279 24.4507 24.6234 26.7493 25.4682C28.0531 25.961 29.4725 25.9183 30.7989 25.5487C32.0575 24.9955 33.301 24.2237 34.0069 23.0092C34.8384 21.5811 35.2982 19.8286 34.7832 18.2094C34.3611 16.2507 32.8739 14.6541 31.0275 13.9426C28.6736 12.9595 25.8073 13.7942 24.1719 15.7001C23.2022 16.8366 22.6143 18.3326 22.7048 19.8387Z\"\n                        fill=\"#2BADD4\" \/>\n                <\/svg>\n            <\/div>\n            <div class=\"text\">\n                <h3>Pro Tip<\/h3>\n                <p>Run a documentation audit on your most recent 10 M45.3 encounters. Flag any chart where the anatomical region is described only as &lsquo;spine&rsquo; or &lsquo;back&rsquo; without specifying the cervicothoracic segment. Those encounters are candidates for a physician query before claim submission.<\/p>\n            <\/div>\n        <\/div>\n    \n\n\n<h2 class=\"wp-block-heading\">Common coding errors and how to avoid them<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The patterns below drive most of the denial and audit risk on ankylosing spondylitis claims. The same specificity trap runs through the whole M45 family.<\/p>\n\n\n\n<table style=\"width:100%;border-collapse:separate;border-spacing:0;border-radius:12px;overflow:hidden;font-size:15px;line-height:1.5;margin:1.5em 0 2em;box-shadow:0 2px 12px rgba(0,0,0,0.08)\">\n<thead>\n<tr>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Error<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Root cause<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Correction<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Using M45.9 when region is documented<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Coder defaults to unspecified rather than reviewing imaging and notes for region<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Code to the highest specificity when documentation supports it. M45.9 is only valid when region truly cannot be determined.<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Coding M45.3 for a pediatric patient<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Adult diagnosis restriction overlooked when the patient is under 15<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Verify patient age before coding. For juvenile AS, review M08.1 and ask the physician to clarify.<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Using M45 (parent) as the claim code<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Parent category selected instead of billable subcode<\/td>\n<td style=\"padding:12px 16px;color:#374151\">M45 alone is not billable. Always select a specific subcode (M45.0 through M45.9) for claim submission.<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Confusing M45.3 with M46.1 (sacroiliitis)<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Clinical notes describe sacroiliac inflammation without confirming AS, so the coder assigns an AS code without confirmation<\/td>\n<td style=\"padding:12px 16px;color:#374151\">M46.1 (Sacroiliitis, not elsewhere classified) is appropriate when sacroiliac joint inflammation is confirmed but full AS diagnosis is not yet established.<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Coding M45.3 with an incorrect year edition<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Using a prior-year tabular list without verifying FY2026 edition validity<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Check the CDC tabular list for the current fiscal year before you submit. M45.3 is valid for FY2026, effective October 1, 2025.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<h2 class=\"wp-block-heading\">Differential diagnosis codes related to M45.3<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Several conditions overlap with cervicothoracic AS on presentation. Accurate differential coding protects against medical necessity rejections and supports cleaner prior authorization. Codes such as M46.1 and M54.2 often reach the claim before AS is confirmed.<\/p>\n\n\n\n<table style=\"width:100%;border-collapse:separate;border-spacing:0;border-radius:12px;overflow:hidden;font-size:15px;line-height:1.5;margin:1.5em 0 2em;box-shadow:0 2px 12px rgba(0,0,0,0.08)\">\n<thead>\n<tr>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Code<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Descriptor<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">When to use instead of M45.3<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M46.1<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Sacroiliitis, not elsewhere classified<\/td>\n<td style=\"padding:12px 16px;color:#374151\">SI joint inflammation confirmed but full AS diagnosis not yet established<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M46.1 + M45.x<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Sacroiliitis with confirmed AS at another spinal level<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Both codes may be used together when SI inflammation co-exists with confirmed AS<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M47.22<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Other spondylosis with radiculopathy, cervical region<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Degenerative rather than inflammatory, with no HLA-B27 positivity, ESR\/CRP elevation, or AS history<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M08.1<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Juvenile ankylosing spondylitis<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Patient is under 16 at time of diagnosis; onset before age 16<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M05.79<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Rheumatoid arthritis with rheumatoid factor, multiple sites<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Seropositive RA confirmed, and differentiated from AS by positive RF\/anti-CCP rather than HLA-B27<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M54.2<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Cervicalgia<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Symptom code only, used when AS is not yet confirmed and neck pain is the presenting complaint<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">M46.42<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Discitis, unspecified, cervical region<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Disc space inflammation without confirmed spondyloarthropathy, often infectious or reactive<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<p class=\"wp-block-paragraph\">M45.3 and an M47 spondylosis code such as M47.9 should not both be applied to the same spinal region in one encounter. Spondylosis implies a degenerative cause, which does not fit the inflammatory classification of AS.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Related CPT codes for ankylosing spondylitis billing<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">M45.3 appears on claims next to the procedure codes that follow the usual management pathway for cervicothoracic AS. Practices that offer osteopathy or physical therapy alongside rheumatology meet these pairings often. Reimbursement follows each payer&rsquo;s policy, so verify coverage and prior authorization before you submit.<\/p>\n\n\n\n<table style=\"width:100%;border-collapse:separate;border-spacing:0;border-radius:12px;overflow:hidden;font-size:15px;line-height:1.5;margin:1.5em 0 2em;box-shadow:0 2px 12px rgba(0,0,0,0.08)\">\n<thead>\n<tr>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">CPT code<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Description<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Clinical context<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">99213-99215<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Office or other outpatient visit, established patient<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Routine rheumatology follow-up, with the level set by medical decision making or total time<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">99203-99205<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Office or other outpatient visit, new patient<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Initial rheumatology evaluation for AS workup<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">72040<\/td>\n<td style=\"padding:12px 16px;color:#374151\">X-ray, cervical spine, 2 or 3 views<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Imaging to evaluate syndesmophytes at cervicothoracic junction<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">72141<\/td>\n<td style=\"padding:12px 16px;color:#374151\">MRI cervical spine without contrast<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Detection of early inflammatory changes not visible on plain film<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">97110<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Therapeutic exercises, each 15 minutes<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Physical therapy for cervical spine mobility and posture in AS<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">97012<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Mechanical traction (untimed, billed once per session)<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Used in PT management of cervical AS with radicular symptoms<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">86812<\/td>\n<td style=\"padding:12px 16px;color:#374151\">HLA typing, A, B, or C (eg, A10, B7, B27), single antigen<\/td>\n<td style=\"padding:12px 16px;color:#374151\">HLA-B27 laboratory testing to support AS diagnosis<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">20610<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Arthrocentesis, major joint or bursa<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Joint aspiration for diagnostic fluid analysis in early AS workup<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<p class=\"wp-block-paragraph\">Biologic therapy management adds administration and drug codes for TNF inhibitors and IL-17 inhibitors. Verify payer-specific prior authorization for biologic claims before submission, because coverage criteria vary by plan and formulary.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">How practice management software supports M45.3 coding accuracy<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Most coding errors on ICD-10 Code M45.3 trace back to thin documentation at the point of care. A physician records \u201ccervical spine AS\u201d without naming the junction level, or cites imaging without recording the report date.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Practice management software like Pabau keeps ICD-10-CM code selection and clinical documentation in the same workflow. Clinicians enter anatomical findings straight into structured encounter notes, and those entries reach the billing team without retyping. Pabau&rsquo;s claims management software then carries the diagnosis through to the claim.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Structured intake and templated encounter notes also remove the blank field that pushes coders toward M45.9. By the time the claim is built, the region of involvement is already on the chart.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/cdn.pabau.com\/cdn\/attachments\/pulse\/content-engine\/diagnostic_codes\/icd-10-code-m453\/automate-claims-through-healthcode.webp\" alt=\"Automated claims and billing in Pabau\"\/><figcaption class=\"wp-element-caption\"><em>Pabau automates claims and billing, so an M45.3 encounter reaches the payer with its documentation already attached.<\/em><\/figcaption><\/figure>\n\n\n\n<div style=\"height:35px;width:800px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Pabau&rsquo;s patient record management stores imaging references and lab results next to the encounter notes, HLA-B27 included. Every documentation element M45.3 needs is there when the coder opens the chart. Practices running physical therapy alongside rheumatology keep both schedules and both billing streams in the same system.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/cdn.pabau.com\/cdn\/attachments\/pulse\/content-engine\/diagnostic_codes\/icd-10-code-m453\/comprehensive-emr-patient-record-management.webp\" alt=\"Comprehensive EMR and patient record management in Pabau\"\/><figcaption class=\"wp-element-caption\"><em>Pabau&rsquo;s patient records hold imaging reports, HLA-B27 results, and encounter notes in one file, so nothing is missing at coding time.<\/em><\/figcaption><\/figure>\n\n\n\n<div style=\"height:35px;width:800px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n        <div id=\"pro_tip\">\n            <div class=\"img\">\n                <svg width=\"42\" height=\"42\" viewBox=\"0 0 42 42\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                    <path fill-rule=\"evenodd\" clip-rule=\"evenodd\"\n                        d=\"M12.6383 19.5238C12.6632 21.2071 12.8734 22.9926 12.0685 24.5523C11.0341 26.8917 8.45076 28.169 7.56292 30.5918C6.63082 33.1061 7.19505 36.185 9.31371 37.9786C10.929 39.5678 13.4183 39.9873 15.6061 39.5463C17.4592 39.073 19.1049 37.8388 19.9706 36.1608C20.781 34.7141 20.7866 32.9904 20.5293 31.3985C20.1006 29.3092 18.3775 27.8705 16.9807 26.362C14.8814 24.1005 14.6684 20.6854 15.595 17.8915C16.4331 15.4768 19.0026 14.2344 20.0425 11.9461C20.7202 10.6769 20.7506 9.20327 20.6068 7.81304C20.1864 5.40098 18.3139 3.23631 15.8716 2.56674C13.9742 2.03969 11.8224 2.30052 10.1739 3.37614C8.70522 4.34688 7.5878 5.86618 7.28356 7.58178C6.76081 9.82981 7.53525 12.2822 9.20307 13.9118C10.7658 15.4741 12.4806 17.2273 12.6383 19.5238Z\"\n                        fill=\"#2BADD4\" \/>\n                    <path fill-rule=\"evenodd\" clip-rule=\"evenodd\"\n                        d=\"M22.7048 19.8387C22.6822 22.3279 24.4507 24.6234 26.7493 25.4682C28.0531 25.961 29.4725 25.9183 30.7989 25.5487C32.0575 24.9955 33.301 24.2237 34.0069 23.0092C34.8384 21.5811 35.2982 19.8286 34.7832 18.2094C34.3611 16.2507 32.8739 14.6541 31.0275 13.9426C28.6736 12.9595 25.8073 13.7942 24.1719 15.7001C23.2022 16.8366 22.6143 18.3326 22.7048 19.8387Z\"\n                        fill=\"#2BADD4\" \/>\n                <\/svg>\n            <\/div>\n            <div class=\"text\">\n                <h3>Pro Tip<\/h3>\n                <p>Build a rheumatology encounter template that includes a mandatory &lsquo;Spinal region(s) affected&rsquo; dropdown with all M45 subcodes listed. When the physician selects the cervicothoracic region, the coder sees it immediately, and nobody has to reconstruct the chart later.<\/p>\n            <\/div>\n        <\/div>\n    \n\n\n<h2 class=\"wp-block-heading\">Related ICD-10 codes<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/pabau.com\/diagnostic-codes\/icd-10-code-m5126\/\">ICD-10 code M51.26 \u2014 Lumbar Disc Displacement<\/a><\/li>\n\n\n<li><a href=\"https:\/\/pabau.com\/diagnostic-codes\/icd-10-code-m455\/\">ICD-10 Code M45.5 \u2014 Ankylosing spondylitis of thoracolumbar region<\/a><\/li>\n\n\n<li><a href=\"https:\/\/pabau.com\/diagnostic-codes\/icd-10-code-m457\/\">ICD-10 Code M45.7 \u2014 Ankylosing spondylitis of lumbosacral region<\/a><\/li>\n<\/ul>\n\n\n        <div id=\"book_a_demo\">\n            <div class=\"left-side\">\n                <div class=\"logo\">\n                    <img decoding=\"async\"\n                        src=\"https:\/\/pabau.com\/wp-content\/uploads\/2026\/01\/Logo.svg\"\n                        alt=\"Logo\"\n                        loading=\"lazy\"\n                    \/>\n                <\/div>\n\n                <h3 class=\"heading\">\n                    Reduce coding errors and simplify rheumatology billing                <\/h3>\n\n                <p class=\"description\">\n                    Pabau&rsquo;s claims management tools support accurate ICD-10-CM code entry, complete documentation workflows, and cleaner claim submission for musculoskeletal practices.                <\/p>\n\n                <div class=\"button-group\">\n                    <a href=\"\/book-demo\/\" class=\"btn btn-scale-effect btn-cta-color btn-md\">\n                        <span class=\"btn-text\">Book a demo<\/span>\n                        <div class=\"btn-icon btn-icon-right\" aria-hidden=\"true\">\n                            <svg\n                                width=\"14\"\n                                height=\"12\"\n                                viewBox=\"0 0 14 12\"\n                                fill=\"none\"\n                                xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\n                            >\n                                <path\n                                    d=\"M0.75 4.77295C0.335786 4.77295 0 5.10874 0 5.52295C0 5.93716 0.335786 6.27295 0.75 6.27295V5.52295V4.77295ZM13.2803 6.05328C13.5732 5.76039 13.5732 5.28551 13.2803 4.99262L8.50736 0.219648C8.21447 -0.073245 7.73959 -0.073245 7.4467 0.219648C7.15381 0.512542 7.15381 0.987415 7.4467 1.28031L11.6893 5.52295L7.4467 9.76559C7.15381 10.0585 7.15381 10.5334 7.4467 10.8263C7.73959 11.1191 8.21447 11.1191 8.50736 10.8263L13.2803 6.05328ZM0.75 5.52295V6.27295L12.75 6.27295V5.52295V4.77295L0.75 4.77295V5.52295Z\"\n                                    fill=\"currentColor\"\n                                ><\/path>\n                            <\/svg>\n                        <\/div>\n                    <\/a>\n                <\/div>\n            <\/div>\n\n            <div class=\"right-side\">\n                <img decoding=\"async\"\n                    src=\"https:\/\/pabau.com\/wp-content\/uploads\/2026\/01\/Home-Page-Concept-4.webp\"\n                    alt=\"Pabau practice management dashboard\"\n                    loading=\"lazy\"\n                \/>\n            <\/div>\n        <\/div>\n        \n\n\n<h2 class=\"wp-block-heading\">Conclusion<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">ICD-10 Code M45.3 is one of the most consistently undercoded diagnoses in rheumatology billing. The cause sits upstream, in a chart that never records the anatomical detail the code needs. When the cervicothoracic region is documented, code it. Falling back on M45.9 with the region in hand carries compliance risk of its own.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Practices that build the documentation into the encounter itself see the sharpest drop in M45-family errors. Retrospective chart review never catches as much, and it costs the coder time nobody has. <a href=\"https:\/\/pabau.com\/book-demo\/\">Book a demo<\/a> to see how Pabau keeps M45.3 documentation and claims in one workflow.<\/p>\n\n\n        <div id=\"expert_picks\">\n            <div class=\"header\">\n                                    <img decoding=\"async\" src=\"https:\/\/pabau.com\/wp-content\/uploads\/2025\/11\/Expert-Picks.svg\" alt=\"Continue your research\" height=\"42\" width=\"42\">\n                                <h3>Continue your research<\/h3>\n            <\/div>\n            <div class=\"content\">\n                                                            <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#54B2D3\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p><strong>Coding AS across more than one spinal region?<\/strong> <a href=\"https:\/\/pabau.com\/diagnostic-codes\/icd-10-code-m450\/\">M45.0<\/a> sets out the multiple-sites code and when it beats a single-region subcode.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#54B2D3\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p><strong>Documenting ankylosing spondylitis lower down the spine?<\/strong> <a href=\"https:\/\/pabau.com\/diagnostic-codes\/icd-10-code-m457\/\">M45.7<\/a> walks through the lumbosacral subcode and the imaging findings that support it.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#54B2D3\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p><strong>Ruling out seropositive rheumatoid arthritis?<\/strong> <a href=\"https:\/\/pabau.com\/diagnostic-codes\/icd-10-code-m05a\/\">M05.A<\/a> explains how abnormal rheumatoid factor and ACPA results change the coding decision.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#54B2D3\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p><strong>Billing an open spinal biopsy?<\/strong> <a href=\"https:\/\/pabau.com\/procedure-codes\/cpt-code-20251\/\">20251<\/a> covers the billing rules, modifiers, and documentation for an open vertebral body biopsy.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#54B2D3\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p><strong>Working through inflammatory differentials?<\/strong> <a href=\"https:\/\/pabau.com\/diagnostic-codes\/icd-10-code-m352\/\">M35.2<\/a> sets out the Beh\u00e7et&rsquo;s disease coding rules and the systemic findings behind them.<\/p>\n                        <\/div>\n                                                <\/div>\n        <\/div>\n    \n\n\n<h2 class=\"wp-block-heading\">Frequently asked questions<\/h2>\n\n\n\n<div class=\"schema-faq wp-block-yoast-faq-block\"><div class=\"schema-faq-section\" id=\"faq-question-1785753276037\"><h3 class=\"schema-faq-question\">What does ICD-10 Code M45.3 mean?<\/h3> <p class=\"schema-faq-answer\">ICD-10 Code M45.3 is a billable, specific ICD-10-CM diagnosis code describing ankylosing spondylitis (AS) of the cervicothoracic region, which corresponds to the C7-T1 vertebral junction. It is valid for FY2026 (effective October 1, 2025) and applies to patients aged 15 years and older. The code falls under the M45 category (ankylosing spondylitis) within Chapter 13 of ICD-10-CM.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1785753276038\"><h3 class=\"schema-faq-question\">Is M45.3 a billable ICD-10-CM code?<\/h3> <p class=\"schema-faq-answer\">Yes, M45.3 is a billable and specific ICD-10-CM code confirmed by the CDC\/NCHS FY2026 tabular list. It can be used directly on claims for reimbursement purposes, unlike the parent category M45, which is not billable. Always verify the code remains valid for the applicable fiscal year before submission.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1785753276039\"><h3 class=\"schema-faq-question\">What is the difference between M45.3 and M45.9?<\/h3> <p class=\"schema-faq-answer\">M45.3 designates ankylosing spondylitis specifically affecting the cervicothoracic region (C7-T1). M45.9 is the unspecified site code and should only be used when the affected spinal region cannot be determined from available documentation. If the physician&rsquo;s note or imaging report identifies the cervicothoracic region, M45.3 is the correct code and M45.9 is a coding error.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1785753276040\"><h3 class=\"schema-faq-question\">What documentation is required to use ICD-10 Code M45.3?<\/h3> <p class=\"schema-faq-answer\">Documentation must name the cervicothoracic region or the C7-T1 vertebral segment explicitly. It also needs a confirmed AS diagnosis in the assessment section, supporting MRI or radiograph findings, HLA-B27 laboratory status, and inflammatory symptom characteristics. The patient must be aged 15 years or older. Missing any of these elements may result in a payer query or claim denial.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1785753276041\"><h3 class=\"schema-faq-question\">What CPT codes are commonly paired with M45.3?<\/h3> <p class=\"schema-faq-answer\">Commonly paired CPT codes include 99213-99215 (established outpatient visits), 72040 (cervical spine X-ray), 72141 (cervical MRI without contrast), 97110 (therapeutic exercise), and 86812 (HLA-B27 typing). CPT code selection depends on the specific services rendered during the encounter. Reimbursement and prior authorization requirements vary by payer and plan.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1785753276042\"><h3 class=\"schema-faq-question\">Does ICD-10 Code M45.3 have an age restriction?<\/h3> <p class=\"schema-faq-answer\">Yes. M45.3 carries an adult diagnosis restriction applicable to patients aged 15 years and older. For patients under 15 presenting with juvenile ankylosing spondylitis, M08.1 (Juvenile ankylosing spondylitis) is the appropriate code family. Applying M45.3 to a pediatric patient without documented clinical justification is a coding error.<\/p> <\/div> <\/div>\n","protected":false},"excerpt":{"rendered":"<p>ICD-10 Code M45.3: Definition and billable status ICD-10 Code M45.3 is a billable, specific ICD-10-CM diagnosis code. Its official descriptor is Ankylosing spondylitis of cervicothoracic region, the C7-T1 junction. The code carries an adult diagnosis restriction, so it applies to patients aged 15 years and older. It took effect on October 1, 2025 under the [&hellip;]<\/p>\n","protected":false},"author":81,"featured_media":171326,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_yoast_wpseo_linkdex":"","_yoast_wpseo_content_score":"","_yoast_wpseo_is_cornerstone":"","_yoast_wpseo_keywordsynonyms":"","_yoast_wpseo_focuskw_text_input":"","_seo_original_html":"","footnotes":""},"categories":[1433,1549,1550,1125],"tags":[1586,3259,2679,1305,2635],"class_list":["post-171327","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-billing-codes","category-diagnostic-codes","category-icd-10-cm","category-musculoskeletal-pain-management","tag-billing-guide","tag-cervical-spine","tag-diagnosis-code","tag-icd-10-codes","tag-rheumatology-coding"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v28.2 (Yoast SEO v28.2) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>ICD-10 Code M45.3: Ankylosing spondylitis billing guide 2026<\/title>\n<meta name=\"description\" content=\"M45.3 covers ankylosing spondylitis at the C7-T1 junction. Code it whenever the notes name the region, or the claim loses specificity.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/\" \/>\n<meta property=\"og:locale\" content=\"fr_FR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"ICD-10 Code M45.3: Ankylosing spondylitis billing guide 2026\" \/>\n<meta property=\"og:description\" content=\"M45.3 covers ankylosing spondylitis at the C7-T1 junction. Code it whenever the notes name the region, or the claim loses specificity.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/\" \/>\n<meta property=\"og:site_name\" content=\"Pabau\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/Pabau\/\" \/>\n<meta property=\"article:published_time\" content=\"2026-08-04T07:04:15+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-08-17T12:29:31+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/pabau.com\/wp-content\/uploads\/2026\/08\/icd-10-code-m453.webp\" \/>\n\t<meta property=\"og:image:width\" content=\"1200\" \/>\n\t<meta property=\"og:image:height\" content=\"630\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/webp\" \/>\n<meta name=\"author\" content=\"Aleksandar Kochovski\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@pabaucrm\" \/>\n<meta name=\"twitter:site\" content=\"@pabaucrm\" \/>\n<meta name=\"twitter:label1\" content=\"\u00c9crit par\" \/>\n\t<meta name=\"twitter:data1\" content=\"Aleksandar Kochovski\" \/>\n\t<meta name=\"twitter:label2\" content=\"Dur\u00e9e de lecture estim\u00e9e\" \/>\n\t<meta name=\"twitter:data2\" content=\"11 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/\"},\"author\":{\"name\":\"Aleksandar Kochovski\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/#\\\/schema\\\/person\\\/73b672a49e20bfba8161e3c17ee3dda2\"},\"headline\":\"ICD-10 Code M45.3: Ankylosing spondylitis of the cervicothoracic region\",\"datePublished\":\"2026-08-04T07:04:15+00:00\",\"dateModified\":\"2026-08-17T12:29:31+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/\"},\"wordCount\":2199,\"publisher\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/pabau.com\\\/wp-content\\\/uploads\\\/2026\\\/08\\\/icd-10-code-m453.webp\",\"keywords\":[\"Billing Guide\",\"Cervical spine\",\"Diagnosis code\",\"ICD-10 codes\",\"Rheumatology coding\"],\"articleSection\":[\"Billing Codes\",\"Diagnostic Codes\",\"ICD-10-CM\",\"Musculoskeletal &amp; Pain Management\"],\"inLanguage\":\"fr-FR\"},{\"@type\":[\"WebPage\",\"FAQPage\"],\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/\",\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/\",\"name\":\"ICD-10 Code M45.3: Ankylosing spondylitis billing guide 2026\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/pabau.com\\\/wp-content\\\/uploads\\\/2026\\\/08\\\/icd-10-code-m453.webp\",\"datePublished\":\"2026-08-04T07:04:15+00:00\",\"dateModified\":\"2026-08-17T12:29:31+00:00\",\"description\":\"M45.3 covers ankylosing spondylitis at the C7-T1 junction. 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It combines scheduling, electronic health records, clinical forms, payments, marketing automation, reporting, and patient engagement tools into one secure cloud system to help practices streamline operations and grow their business.\",\"foundingDate\":\"2011-10-20\",\"numberOfEmployees\":{\"@type\":\"QuantitativeValue\",\"minValue\":\"201\",\"maxValue\":\"500\"}},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/#\\\/schema\\\/person\\\/73b672a49e20bfba8161e3c17ee3dda2\",\"name\":\"Aleksandar Kochovski\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"fr-FR\",\"@id\":\"https:\\\/\\\/pabau.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/cropped-aleksandar-kochovski-profile-picture-96x96.jpeg\",\"url\":\"https:\\\/\\\/pabau.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/cropped-aleksandar-kochovski-profile-picture-96x96.jpeg\",\"contentUrl\":\"https:\\\/\\\/pabau.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/cropped-aleksandar-kochovski-profile-picture-96x96.jpeg\",\"caption\":\"Aleksandar Kochovski\"},\"description\":\"Aleksandar is a content strategist and editor working in tech publishing, with a background in higher education. He specializes in topics around compliance in software solutions. When he's not writing at Pabau, you can find him tending to his bonsai collection or hitting the gym.\",\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/blog\\\/author\\\/aleksandar-kochovski\\\/\"},{\"@type\":\"Question\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#faq-question-1785753276037\",\"position\":1,\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#faq-question-1785753276037\",\"name\":\"What does ICD-10 Code M45.3 mean?\",\"answerCount\":1,\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"ICD-10 Code M45.3 is a billable, specific ICD-10-CM diagnosis code describing ankylosing spondylitis (AS) of the cervicothoracic region, which corresponds to the C7-T1 vertebral junction. It is valid for FY2026 (effective October 1, 2025) and applies to patients aged 15 years and older. The code falls under the M45 category (ankylosing spondylitis) within Chapter 13 of ICD-10-CM.\",\"inLanguage\":\"fr-FR\"},\"inLanguage\":\"fr-FR\"},{\"@type\":\"Question\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#faq-question-1785753276038\",\"position\":2,\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#faq-question-1785753276038\",\"name\":\"Is M45.3 a billable ICD-10-CM code?\",\"answerCount\":1,\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Yes, M45.3 is a billable and specific ICD-10-CM code confirmed by the CDC\\\/NCHS FY2026 tabular list. It can be used directly on claims for reimbursement purposes, unlike the parent category M45, which is not billable. Always verify the code remains valid for the applicable fiscal year before submission.\",\"inLanguage\":\"fr-FR\"},\"inLanguage\":\"fr-FR\"},{\"@type\":\"Question\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#faq-question-1785753276039\",\"position\":3,\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#faq-question-1785753276039\",\"name\":\"What is the difference between M45.3 and M45.9?\",\"answerCount\":1,\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"M45.3 designates ankylosing spondylitis specifically affecting the cervicothoracic region (C7-T1). M45.9 is the unspecified site code and should only be used when the affected spinal region cannot be determined from available documentation. If the physician's note or imaging report identifies the cervicothoracic region, M45.3 is the correct code and M45.9 is a coding error.\",\"inLanguage\":\"fr-FR\"},\"inLanguage\":\"fr-FR\"},{\"@type\":\"Question\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#faq-question-1785753276040\",\"position\":4,\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#faq-question-1785753276040\",\"name\":\"What documentation is required to use ICD-10 Code M45.3?\",\"answerCount\":1,\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Documentation must name the cervicothoracic region or the C7-T1 vertebral segment explicitly. It also needs a confirmed AS diagnosis in the assessment section, supporting MRI or radiograph findings, HLA-B27 laboratory status, and inflammatory symptom characteristics. The patient must be aged 15 years or older. Missing any of these elements may result in a payer query or claim denial.\",\"inLanguage\":\"fr-FR\"},\"inLanguage\":\"fr-FR\"},{\"@type\":\"Question\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#faq-question-1785753276041\",\"position\":5,\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/diagnostic-codes\\\/icd-10-code-m453\\\/#faq-question-1785753276041\",\"name\":\"What CPT codes are commonly paired with M45.3?\",\"answerCount\":1,\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Commonly paired CPT codes include 99213-99215 (established outpatient visits), 72040 (cervical spine X-ray), 72141 (cervical MRI without contrast), 97110 (therapeutic exercise), and 86812 (HLA-B27 typing). CPT code selection depends on the specific services rendered during the encounter. 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The code falls under the M45 category (ankylosing spondylitis) within Chapter 13 of ICD-10-CM.","inLanguage":"fr-FR"},"inLanguage":"fr-FR"},{"@type":"Question","@id":"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/#faq-question-1785753276038","position":2,"url":"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/#faq-question-1785753276038","name":"Is M45.3 a billable ICD-10-CM code?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Yes, M45.3 is a billable and specific ICD-10-CM code confirmed by the CDC\/NCHS FY2026 tabular list. It can be used directly on claims for reimbursement purposes, unlike the parent category M45, which is not billable. Always verify the code remains valid for the applicable fiscal year before submission.","inLanguage":"fr-FR"},"inLanguage":"fr-FR"},{"@type":"Question","@id":"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/#faq-question-1785753276039","position":3,"url":"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/#faq-question-1785753276039","name":"What is the difference between M45.3 and M45.9?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"M45.3 designates ankylosing spondylitis specifically affecting the cervicothoracic region (C7-T1). M45.9 is the unspecified site code and should only be used when the affected spinal region cannot be determined from available documentation. If the physician's note or imaging report identifies the cervicothoracic region, M45.3 is the correct code and M45.9 is a coding error.","inLanguage":"fr-FR"},"inLanguage":"fr-FR"},{"@type":"Question","@id":"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/#faq-question-1785753276040","position":4,"url":"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/#faq-question-1785753276040","name":"What documentation is required to use ICD-10 Code M45.3?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Documentation must name the cervicothoracic region or the C7-T1 vertebral segment explicitly. It also needs a confirmed AS diagnosis in the assessment section, supporting MRI or radiograph findings, HLA-B27 laboratory status, and inflammatory symptom characteristics. The patient must be aged 15 years or older. Missing any of these elements may result in a payer query or claim denial.","inLanguage":"fr-FR"},"inLanguage":"fr-FR"},{"@type":"Question","@id":"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/#faq-question-1785753276041","position":5,"url":"https:\/\/pabau.com\/fr\/diagnostic-codes\/icd-10-code-m453\/#faq-question-1785753276041","name":"What CPT codes are commonly paired with M45.3?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Commonly paired CPT codes include 99213-99215 (established outpatient visits), 72040 (cervical spine X-ray), 72141 (cervical MRI without contrast), 97110 (therapeutic exercise), and 86812 (HLA-B27 typing). CPT code selection depends on the specific services rendered during the encounter. 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