Clinical calculator summary
Original Mirels Score for Metastatic Long-Bone Lesions (1989)
Clinical calculator summary
Original Mirels Score for Metastatic Long-Bone Lesions (1989)
This route implements the original 1989 Mirels score for an intact long-bone lesion in an adult with known metastatic malignancy, using clinical assessment and reviewed plain radiographs before radiotherapy.
Evidence-based context for fast calculator use
- Purpose:
- Interprets the original 1989 Mirels total for an intact metastatic long-bone lesion using four clinician-selected source categories.
- Population:
- patients undergoing skeletal metastasis stability, fracture-risk, survival, or operative assessment
- Factors:
- Eligible long-bone site category, Source pain category, Radiographic lesion nature, Clinician-selected radiographic size category
- Reference:
- Mirels H. Clin Orthop Relat Res. 1989;(249):256-264. PMID 2684463. Later reviews document low external specificity and interobserver variability.
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Original Mirels Score for Metastatic Long-Bone Lesions (1989)
Clinical Context & Background
This route implements the original 1989 Mirels score for an intact long-bone lesion in an adult with known metastatic malignancy, using clinical assessment and reviewed plain radiographs before radiotherapy. It adds four explicit source points: site, functional pain category, radiographic lesion nature, and categorical lesion size. The score does not derive categories from images or accept a numeric cortical ratio.
The original cohort comprised 38 patients with 78 lesions irradiated without prophylactic fixation and observed for fracture for six months. Its total-specific percentages are small historical cohort observations, not individualized current probabilities or certainties. Score 8 has a source conflict: the primary abstract states >=8, while the reproduced clinical table treats 8 as a clinical-judgment zone and >=9 as the commonly used threshold. A score never mandates fixation, declares radiotherapy alone safe, or selects treatment.
The selected site category asserts an eligible upper- or lower-limb long bone or trochanteric femur. Spine, pelvis outside the proximal femur, ribs, scapula, skull, small bones, primary bone tumors, benign lesions, completed fractures, stabilized lesions, and inadequate imaging are outside scope. Multiple myeloma and previously irradiated lesions receive explicit transportability warnings. Modified Mirels systems and proposed upper-limb >=7 thresholds are separate models and are not merged here.
Formula Logic
Explicit source mapping: site points + pain points + lesion-nature points + categorical size points; total 4-12 with no rounding.Reference Data
| Original total | Historical cohort observation | Neutral interpretation |
|---|---|---|
| 4, 5, 6, 7 | 0%, 0%, 0%, 4% | Below commonly used >=9 threshold; not a safety determination |
| 8 | 15% | Source conflict: abstract >=8 versus reproduced table judgment zone |
| 9, 10, 11, 12 | 33%, 72%, 96%, 100% | Meets commonly used >=9 threshold; specialist assessment remains separate |
Clinical Workflow
Use, Interpret, And Continue The Patient Pathway
Expand for workflow guidance, limitations, examples, and related next steps.
Clinical Workflow
Use, Interpret, And Continue The Patient Pathway
Expand for workflow guidance, limitations, examples, and related next steps.
When To Use
- Use Original Mirels Score for Metastatic Long-Bone Lesions (1989) when interprets the original 1989 Mirels total for an intact metastatic long-bone lesion using four clinician-selected source categories.
- Confirm that the patient, diagnosis, disease phase, and available inputs match the cited model before calculation.
How To Interpret
- Interpret the displayed result using the calculator-specific formula and reference table, spanning 4, 5, 6, 7 through 9, 10, 11, 12.
- A boundary result should prompt input verification and clinical review rather than false precision.
What To Do Next
- Combine the score with neurologic examination, mechanical pain, imaging, oncologic prognosis, radiosensitivity, surgical options, and patient goals.
- Document the inputs, result, timing, and clinical context so the assessment can be reproduced.
Limitations
- Fracture, spinal-instability, survival, and surgical-selection scores measure different domains and cannot substitute for urgent specialist assessment.
- The result supports clinician judgment and does not independently determine treatment.
Validated Population
patients undergoing skeletal metastasis stability, fracture-risk, survival, or operative assessment
How to apply this result
For a representative case, verify Eligible long-bone site category, Source pain category, Radiographic lesion nature, calculate the result, and confirm that its classification matches the highlighted reference band before continuing the disease-specific pathway.
Calculation verification history
Verified
Calculation verification history
Verified: Production browser revalidation
- Five source-backed original Mirels cases were exercised on the public production route through visible controls; 5/5 expected totals and interpretations matched across 4, 7, 8, 9, and 12.
- No unexpected N/A, literal undefined value, stale control, or browser-console error was observed.
Case-level evidence is retained in validation/browser-revalidation/mirels-bone-metastasis-2026-08-03.json.
: Production browser validation
- Ten source-backed cases were exercised on the public production route through visible browser controls; 10/10 case records passed their expected-versus-observed assertions across 11 visible submissions.
- Overall browser status: failed-console. medium: Production emitted minified React error #418 during route loads/reloads used by this run.
- Case-level inputs, expected and observed results, reset/repeat behavior, failure reproductions, and console evidence are retained in the production-browser evidence record.
Case-level production evidence is retained in validation/browser-production/mirels-bone-metastasis.json.
: Input workflow simplified and revalidated
- Reduced the public form to result-, branch-, unit-, and applicability-changing inputs; removed or consolidated non-scoring, administrative, and duplicate questions.
- Preserved the verified calculation or report-interpretation logic, thresholds, model version, component logic, and supported result pathways behind strict deterministic adapters.
- Passed the calculator-specific regression audit, adapter-parity and malformed-input checks, the 144-calculator input-quality audit, and the 43-calculator entry-burden audit.
: Full validation
- 190/190 independently expected scoring, lookup, malformed-input, applicability, wording, trace, UI, content, registry, report, history, and mirror assertions passed.
- This is implementation verification, not independent clinical validation or treatment guidance.
: Calculation/input correction
- Removed clinical defaults, Number coercion, Object.values summation, numeric lesion-size inference, and functional/severe pain conflation.
- Added the exact eight-key immutable contract, all nine historical total lookups, neutral applicability statuses, source-conflict trace, and UI reset behavior.
- Separated original, modified, upper-limb, myeloma, and previously irradiated contexts.
Included in the current validation report.
: Content reconciliation
- Replaced mandatory fixation, radiotherapy-alone safety, and individualized-risk language in the dedicated article and breast guideline.
- Corrected the permanent route, glossary/blog identity, and removed the long-bone tool from the brain-metastases hub.
Included in the current validation report.
Verification confirms the calculator implementation against the cited model; it is not independent clinical validation, regulatory approval, or medical advice.
Frequently Asked Questions
When should Original Mirels Score for Metastatic Long-Bone Lesions (1989) be used?
Use it for patients undergoing skeletal metastasis stability, fracture-risk, survival, or operative assessment when all required inputs and the intended clinical setting are confirmed.
Can Original Mirels Score for Metastatic Long-Bone Lesions (1989) determine treatment by itself?
No. Interpret the result with the cited evidence, complete clinical assessment, current guidelines, and patient-specific goals.
Evidence-based oncology decision support. Verify with clinical guidelines.