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KneeSchool/Imaging Academy/Reporting Post-operative Knees

Reporting Post-operative Knees

Page 5.20.7 · Imaging Reporting Academy · imaging page

A knee that cannot be reported without knowing the operation, measured against an expected appearance that is largely unpublished.

Pipeline status. Editorial draft. Evidence verification did not run. Not consultant reviewed. Not for clinical use.

The same topic at 4 depths

Each tier deepens the one below it and never repeats it. Choose the level you want.

Reporting Post-operative Knees

Choose a depth

For Medical Students

What It Shows

A post-operative report states which construct is present, whether each part is intact, and whether the appearance is expected for the interval. 5.5.3 covers the post-operative protocol.

It is built from radiographs for the hardware and from a protocol adapted for metal when soft tissue is the question. 5.3.2 covers the lateral view.

It matters because the altered anatomy is the new baseline, and a reader without the operative detail reports it as disease. 5.20.8 covers common reporting errors.

How It Is Acquired

Establish which operation was performed before reporting anything. 5.20.1 covers structured reporting.

State the interval since surgery, because the expected appearance changes with it. 5.7.10 covers the graft maturation.

Report each component of the construct separately: the graft, the fixation, the tunnel, the osteotomy. 5.7.12 covers the tunnel assessment.

State what the metal prevented you from assessing. 5.5.3 covers the post-operative protocol.

Repeat the measurements that led to the operation wherever recurrence is the question. 5.16.4 covers the TT-TG measurement.

What Normal Looks Like

The operation named in the report, or the report saying it is not known. 5.20.1 covers structured reporting.

The interval since surgery stated. 5.7.10 covers the graft maturation.

Each part of the construct reported as intact, altered or not assessable. 5.7.12 covers the tunnel assessment.

The effect of the artefact stated rather than left implicit. 5.5.3 covers the post-operative protocol.

A conclusion that distinguishes expected from unexpected. 5.20.8 covers common reporting errors.

What Abnormal Looks Like

A report written without knowing the operation and not saying so. 5.20.8 covers common reporting errors.

Expected signal around a graft or a tunnel reported as infection. 5.7.10 covers the graft maturation.

A structure obscured by metal reported as absent. 5.1.6 covers imaging pitfalls.

A repaired meniscus reported as re-torn against an intact reference. 5.6.13 covers the meniscal repair imaging.

Text copied from the pre-operative report into the post-operative one. 5.20.1 covers structured reporting.

Key Learning Points

  • The operation must be known before the report is written.
  • The interval sets the expected appearance.
  • Each part of the construct is reported separately.
  • Obscured is not the same as absent.
  • The conclusion separates expected from unexpected.

MRCS Level

How It Is Acquired

In a viva the expected answer asks what was done and when.

The expected points are the operation, the interval, the construct part by part, the artefact, and the repeated measurements.

Say that radiographs answer the hardware question better than a scan does. 5.3.2 covers the lateral view.

Say that computed tomography answers union and position where artefact defeats a scan. 5.16.8 covers the 3D reconstructions.

Say that a graft remodels, so an appearance is read against an interval. 5.7.10 covers the graft maturation.

What Abnormal Looks Like

The reasoning expected is that an operated knee carries three questions: whether the repair is intact, whether the fixation is sound, and whether the original problem was addressed. 5.7.11 covers the graft failure.

The first two are structural and the third needs the pre-operative measurements repeated, which is why they belong in one report. 5.16.4 covers the TT-TG measurement.

Artefact is worst beside the implant, which is where the fixation question sits, so a radiograph answers it better. 5.3.2 covers the lateral view.

An intact construct with a recurrent symptom points away from the repair rather than at it. 5.7.11 covers the graft failure.

How Good It Is

Imaging the operated knee is a good test of structural integrity and no test of clinical outcome.

Its best contribution is the fixation, the union and the graft continuity. 5.7.12 covers the tunnel assessment.

It is limited by artefact, by the absence of an agreed expected appearance for most procedures, and by findings that are expected rather than wrong. 5.5.3 covers the post-operative protocol.

No figures appear for accuracy on this page, under decision 028, and no tunnel positions or union intervals appear either: those are published quantities tied to particular techniques and this environment cannot check them.

Key Learning Points

  • An operated knee carries three separate questions.
  • Artefact is worst where the fixation question sits.
  • Computed tomography answers union and position.
  • An intact construct with a symptom points away from the repair.
  • Structural integrity is not clinical outcome.

FRCS Level

How Good It Is

At decision level the report has to separate a technical failure from a wrong operation. 5.7.11 covers the graft failure.

A displaced graft, a non-union or a malpositioned tunnel is technical and visible. 5.7.12 covers the tunnel assessment.

An intact construct with persistent instability points at an unaddressed factor, which the report should name. 5.20.4 covers reporting MCL injuries.

The pre-operative measurements repeated with the same convention are what make that distinction possible. 5.16.4 covers the TT-TG measurement.

A revision question differs from a primary one and needs its own report rather than the old one reread. 5.7.14 covers the revision ACL imaging.

Where It Misleads

The commonest error is reporting the expected post-operative state as a complication. 5.7.10 covers the graft maturation.

Signal around a tunnel months after surgery is read as infection or loosening. 5.5.3 covers the post-operative protocol.

A measurement on an operated knee is compared with a threshold from unoperated ones. 5.16.4 covers the TT-TG measurement.

Prominent hardware that has done its job is read as failure. 5.16.5 covers osteotomy planning.

A reconstruction with no published expected appearance is reported against the native structure. 5.9.7 covers the post-operative medial reconstructions.

Key Learning Points

  • Expected appearances are reported as complications.
  • Signal around a tunnel is read as infection.
  • Operated knees are measured against unoperated thresholds.
  • Prominent hardware is not failed hardware.
  • A native structure is the wrong reference for a reconstruction.

Fellowship Level

Where It Misleads

At fellowship level the patient arrives after surgery done elsewhere, with no operative note and a report written without one. 5.20.1 covers structured reporting.

The construct on the images rarely identifies the technique, and the technique decides the expected appearance. 5.7.9 covers the ACL reconstruction.

Serial studies from different departments to different protocols compare protocols as much as they compare the knee. 5.5.3 covers the post-operative protocol.

A procedure that alters bone permanently makes every later measurement describe the operation rather than the patient. 5.12.8 covers the post-operative imaging.

Cartilage near metal is the least reliable part of the study and is where a revision decision often rests. 5.20.5 covers reporting cartilage lesions.

The useful report gives the operation if known, the interval, each part of the construct, the repeated measurements with their conventions, and what the artefact prevented. 5.20.8 covers common reporting errors.

Key Learning Points

  • The technique is rarely identifiable from the images.
  • Serial studies across departments compare protocols.
  • A bony procedure makes later measurements describe the operation.
  • Cartilage near metal is the least reliable assessment.
  • The report should state what the artefact prevented.

Explore Further

Where this topic came from and where it goes next in the spiral.

References

No reference list is attached to this draft. Evidence verification has not run, because source retrieval was unavailable at generation time. Under the Operations Handbook a missing reference is acceptable and an invented one is a critical failure, so nothing has been cited and no citation marker appears in the text. This page carries no diagnostic accuracy figure, which is decision 028 rather than an omission: the comparative standing of the modalities is standard teaching and a specific sensitivity written from memory is the same class of claim as an invented citation, so ACC-001 refuses the number and the page states the comparison. A reviewer with the literature can add the figures into How Good It Is without restructuring the page. Any measurement here, including a sequence parameter, an angle or a millimetre, is written from standard teaching, has not been checked, and is registered under decision 006 in pipeline/config/figures with a verification state of UNVERIFIED_FROM_MEMORY.

Safety. KneeSchool is educational and does not give individual medical advice. Seek urgent assessment for a knee that cannot bear weight after an injury, a hot swollen knee with a fever, or new numbness, weakness or coldness in the leg or foot.