Tendon Procedures

For Medical Students

What It Shows

Several procedures put a needle into or beside a tendon: fenestration of tendinopathic tissue, sheath injection, and calcific lavage. 5.4.6 covers the patellar tendon.

Ultrasound identifies the abnormal tissue, distinguishes intratendinous from peritendinous space, and guides accordingly. 5.4.16 covers the knee injection.

It matters because these procedures target different tissue compartments, and the imaging is what tells them apart. 5.2.8 covers reflection.

How It Is Acquired

Identify the abnormal area within the tendon, since fenestration targets that tissue specifically. 5.4.6 covers the patellar tendon.

Identify the sheath or peritendinous space as a separate compartment. 5.5.12 covers the bursa.

Identify any calcification and its acoustic shadow, which is the lavage target. 5.14.4 covers crystal arthropathy.

Keep the needle in plane and confirm which compartment the tip is in. 5.2.8 covers reflection.

Record which compartment was entered, because the procedures are different. 5.20.1 covers structured reporting.

What Normal Looks Like

A needle in plane with its tip in the intended compartment. 5.2.8 covers reflection.

Fenestration passes visible within the abnormal tissue. 5.4.6 covers the patellar tendon.

Injectate confined to the sheath when a sheath procedure was intended. 5.5.12 covers the bursa.

A documented compartment and approach. 5.20.1 covers structured reporting.

What Abnormal Looks Like

A tip in the tendon when the sheath was intended, or the reverse. 5.5.12 covers the bursa.

Injectate tracking into the tendon substance unintentionally. 5.4.16 covers the knee injection.

Calcification not engaged by the needle, so lavage does not proceed. 5.14.4 covers crystal arthropathy.

A needle out of plane, making the compartment unknown. 5.2.8 covers reflection.

MRCS Level

How It Is Acquired

In a viva the expected answer distinguishes the compartments before describing any technique.

The expected points are the abnormal tissue, the sheath, the calcification, the in plane needle, and the record.

Say that intratendinous and peritendinous are different procedures. 5.5.12 covers the bursa.

Say that calcification is identified by its acoustic shadow. 5.14.4 covers crystal arthropathy.

Say that whether to perform the procedure belongs to the treatment literature. 5.1.7 covers evidence based imaging.

What Abnormal Looks Like

The reasoning expected is that a tendon and its sheath are separate compartments with different responses to an injected agent, so putting material in the wrong one changes which procedure was performed rather than its accuracy. 5.5.12 covers the bursa.

Fenestration deliberately damages tendinopathic tissue to provoke a healing response, which means the target is the abnormal tissue and the imaging has to find it. 5.4.6 covers the patellar tendon.

Calcific deposits reflect strongly and cast a shadow, which is both how they are found and why a needle approaching them must be angled rather than blocked. 5.14.4 covers crystal arthropathy.

A needle out of plane leaves the compartment unknown, which for these procedures is the difference between two different treatments. 5.2.8 covers reflection.

How Good It Is

Ultrasound distinguishes the compartments around a tendon better than any other modality and does not establish that any of these procedures helps.

Its best contribution is compartment level targeting, which is what makes these procedures distinguishable from one another. 5.5.12 covers the bursa.

It is limited to the targeting question, since the indications and outcomes belong to the treatment literature. 5.1.7 covers evidence based imaging.

No figures appear for accuracy on this page, under decision 028, and no outcome or technique figures appear either: pass counts, volumes and response rates are published quantities this environment cannot check.

FRCS Level

How Good It Is

At decision level the imaging contributes the target and the compartment, and the indication sits outside this section.

A discrete abnormal area within a symptomatic tendon is a definable fenestration target. 5.4.6 covers the patellar tendon.

A distended sheath with symptoms is a separate target with a separate procedure. 5.5.12 covers the bursa.

A calcific deposit identified by its shadow is a third. 5.14.4 covers crystal arthropathy.

A discrete tear within a tendinopathic tendon changes the plan, and distinguishing it is an imaging job. 5.4.5 covers the quadriceps tendon.

Where It Misleads

The commonest error is entering the wrong compartment and reporting the intended procedure. 5.5.12 covers the bursa.

An incidental tendon appearance is treated. 5.1.6 covers imaging pitfalls.

A discrete tear is fenestrated as tendinopathy. 5.4.5 covers the quadriceps tendon.

The needle is out of plane and the compartment is assumed. 5.2.8 covers reflection.

A technical success is reported as a clinical outcome. 5.1.7 covers evidence based imaging.

Fellowship Level

Where It Misleads

At fellowship level these procedures close the chapter on the theme it opened with, that the person holding the probe is doing the study and the procedure at once.

The imaging that selects the target, the hand that places the needle and the judgement that the procedure is indicated all belong to one person, which concentrates the decision in a way no other knee imaging does. 5.4.1 covers the anterior knee.

That is the source of ultrasound's unique usefulness and of its weakest accountability, because nothing in the record separates the three. 5.20.1 covers structured reporting.

The target appearances occur in asymptomatic tendons, so the selection step is weaker than the targeting step, and the procedures are judged on the targeting. 5.4.6 covers the patellar tendon.

The outcome literature mixes procedures that differ in compartment, in pass count and in agent, and only the compartment is an imaging variable, so imaging cannot resolve the disagreement. 5.1.7 covers evidence based imaging.

The chapter's conclusion is that ultrasound is unmatched for a superficial structure, for movement and for a needle, and that each of those strengths is recorded in a form that does not survive the examination. 5.2.6 covers sound waves.