UW Shoulder and Elbow Academy

Tuesday, January 14, 2025

The Fundamentals of the Shoulder: Practical Evaluation and Management of the Shoulder - available free of charge.

Back in 1994, four of us published a book entitled Practical Evaluation and Management of the Shoulder, a book that has become a classic. It contains the original descriptions of overstuffing, concavity compression, the Simple Shoulder Test, and the principals shoulder motion, strength, stability and smoothness. It contains printable new patient evaluation and followup forms. It is illustrated by the highly descriptive Steve Lippitt diagrams. In that it is now out of print, many have asked how they might get a copy. I'm pleased to be able to provide a free PDF of the book in its entirety: click here.

You can support cutting edge shoulder research that is leading to better care for patients with shoulder problems, click on this link

Follow on twitter/X: https://x.com/RickMatsen
Follow on facebook: https://www.facebook.com/shoulder.arthritis
Follow on LinkedIn: https://www.linkedin.com/in/rick-matsen-88b1a8133/

Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link)
Shoulder rehabilitation exercises (see this link).

Learning orthopaedics in Hawaii!

I'm thoroughly enjoying and learning lots from

expertly crafted by former fellow and great friend, Tony Romeo.

This is a terrific learning experience for orthopaedic surgeons and PAs of all levels of experience - debutants to masters.

In addition to lots of great times with the Romeos, I had meaningful exchanges with many fellow learners, including Rachel Frank, Chris Ahmad, Julie Bishop, and Michael Amini, past fellows and residents, and other friends. I also had the opportunity to share some of my thoughts on management of shoulder infections, the magic of concavity compression in stabilizing the shoulder, the importance (or lack thereof) of correcting glenoid version to <15 degrees, and Green Orthopaedics (the art and science of devoting more money only when it benefits the patient in terms of comfort, function and safety).

The afternoons gave some time for me to take my camera for walks.

Some of the results are shown below.

Common Myna

Hawaiian Goose

Humpback Whale

Monk Seal Pup

Pacific Golden Plover

Red Crested Cardinal

Warbling White Eye

Western Cattle Egret

All in all, a very special time.

You can support cutting edge shoulder research that is leading to better care for patients with shoulder problems, click on this link

Sunday, January 12, 2025

Stemless anatomic humeral arthroplasty – my January 2025 approach

Stemless humeral components have the advantage of enabling the placement of the humeral articular surface in the desired location independent of the position of a stem in the medullary canal.

As a result, they have become my default for anatomic total shoulder and for the ream and run arthroplasty.

The technique I use is continuing to evolve with experience and from collaboration with my partners, our fellows, our residents, and my colleagues around the world. Below are some elements of my technique as of today. I hope to continue learning.

While this presentation reflects my current use of implants from a particular company, I have no financial or other conflicts of interest with this or any company.

After trimming away the osteophytes

I make a free hand cut (at 135 degrees with the long axis of the humeral shaft and in 30 degrees of retroversion, completely resecting the humeral head just inside the rotator cuff insertion superiorly and posteriorly).

This defines the anatomic position for the humeral head component.

One of the biggest challenges is make sure that the reconstruction does not tighten the shoulder by over lateralizing the proximal humerus in relation to the scapula; this is important for both the anatomic total shoulder

and for the ream and run.

Avoiding overtightening requires the surgeon to be mindful of the effect of humeral head geometry on the volume of the head component, recognizing that the choices of head diameter of curvature and head thickness are limited by the inventory in each company's system.

With the stemless, as with all humeral components, it is important that upper lateral aspect of the head does not extend superiorly to the berm

After the glenoid preparation for either a prosthetic component or a ream and run, a trial head is fit to and positioned on the neck cut and used as a guide for insertion of the guide pin

This pin is used for the humeral preparation

and for insertion of the trial blaze

The trial head is secured to the trial blaze

so that the mobility and the stability of the head on the glenoid can be examined.

The perimeter of the trial head is examined for exposed bone, which is removed with a pinecone bur

I’m always prepared to convert to a short humeral stem for one of several indications:

(1) The bone of the proximal humerus is too soft to securely fix the nucleus. Rather than relying on the "thumb test" or on a preoperative CT to estimate the local bone density, it seems more practical to insert the blaze trial

to see if it fits securely in the bone.

If not, I convert to a short stem positioned to place the head in the previously defined anatomic position.

(2) The fins of the nucleus are too long for the humerus (28).

This is most likely to be an issue in small individuals with soft bone (which leads to consideration of a larger sized nucleus with longer fins). The risk of “too long fins) can be estimated by holding the trial blaze up to the humeral neck (the “eye-ball test”)

If this is a concern, I convert to a short stem positioned to place the head in the previously defined anatomic position.

(3) Intraoperative testing reveals that an anatomically positioned humeral head cannot be stabilized on the glenoid without overstuffing the joint. In this situation I convert to a short stem to support the use of an anteriorly eccentric humeral component

An important element of avoiding stiffness is having a repair of the subscapularis peel that is sufficiently robust that gentle mobilization of the shoulder can be instituted soon after surgery with minimal risk of subscapularis failure. I use 6 sutures of Fiberwire passed through solid bone at the lesser tuberosity.

An additional one or two Fiberwires are placed in the rotator interval capsule to reinforce the subscapularis repair. As shown below, these sutures are passed over the long head tendon of the biceps, which is preserved in almost all cases.

At the conclusion of the case I verify that the shoulder has stability and a full range of assisted flexion, documented with a “parting shot” photograph that is included in the operative note.

This is what I’m doing at the start of 2025. I would welcome comments and suggestions on alternative approaches.

Once again thanks to our residents Jon Yamaguchi and Kevin Khoo for their help with the figures shown here,

You can support cutting edge shoulder research that is leading to better care for patients with shoulder problems, click on this link

Thursday, January 9, 2025

Why the Simple Shoulder Test is my preferred patient reported outcome measure.

Many different shoulder outcome measures have been proposed.

Some ask the patient: "How would you rate your shoulder function as a percentage of normal, with 0% being completely nonfunctional and 100% being completely normal?" or "How would you rate your shoulder today as a percentage of normal, where 0% represents no function and 100% represents normal function?".

Some ask the patient to make a mark on a visual analogue scale

Some ask for a measurement of range of motion that is included in an overall score

Some use computer adaptive testing to derive a single number representing pain and function.

And still others generate a single number based on "hands-on" evaluation of strength and motion by a trained observer combined with patient answers to questions about pain and function.

While each of these may have advantages, my preferred outcome measure is simple, easily accessible to almost all patients, and reflects what the patient believes they can do with their shoulder.

It is the Simple Shoulder Test, a set of twelve "yes" or "no" shoulder function questions:

Is your shoulder comfortable with your arm at rest by your side?
Does your shoulder allow you to sleep comfortably?
Can you reach the small of your back to tuck in your shirt with your hand?
Can you place your hand behind your head with the elbow straight out to the side?
Can you place a coin on a shelf at the level of your shoulder without bending your elbow?
Can you lift one pound (a full pint container) to the level of your shoulder without bending your elbow?
Can you lift eight pounds (a full gallon container) to the level of your shoulder without bending your elbow?
Can you carry 20 pounds at your side with the affected extremity?
Do you think you can toss a softball underhand 10 yards with the affected extremity?
Do you think you can throw a softball overhand 20 yards with the affected extremity?
Can you perform your usual work?
Can you perform your usual sport?

Completion of the SST requires only a pencil and a stamped envelope.

As a result use of the SST avoids the risk of selection bias that can result from excluding those who cannot use a computer or who cannot travel for in a person examination. It also avoid the problems of observer bias and inter-observer variability; the consistent observe this the most important one: the patient.

The easy accessibility of the SST enables long term studies with low percentages of "lost to followup".

Since its introduction by Doug Harman and Steve Lippitt in 1993 it has been used in 1,637 publications in peer reviewed journals at the time of this post and has been translated to and validated in multiple languages, including Spanish, French, German, Italian, Chinese, Japanese, Korean, Portuguese, Dutch, Swedish, Turkish, Russian, Arabic, Hindi, Thai, and Bulgarian, enabling cross-cultural studies.

Instead of yielding a single numerical score (which may have limited meaning to our patients), the SST gathers easily understandable information about the individual's ability to perform 12 separate function. This enables surgeons and patients to understand the ability of a procedure to address the functional deficits of particular importance to the individual.

Some have criticized the Simple Shoulder Test having a "ceiling effect", meaning that some patients can perform all 12 of the functions. However, the "ceiling" is pretty high: a shoulder that can throw 20 yards, lift a full gallon container to the level of the shoulder with the arm held straight, and allow comfortable sleep is an excellent shoulder by any measure.

The SST is a low cost and practical method for surgeons to measure their own effectiveness in treating a wide range of shoulder conditions and to collaborate broadly in clinical research.

Development of the SST

Identifying Common Shoulder Activities:
- The questions were selected after methodologically cataloguing the presenting complaints of patients with a broad range of shoulder conditions.
- The 12 commonest complaints were converted in to simple "yes" "no" questions.
- As a result, the SST focuses on basic, everyday activities that are commonly affected by shoulder dysfunction. These include actions like reaching, lifting, carrying, and activities of daily living such as grooming or dressing.
- The development team aimed for questions that would resonate universally across patients with varying shoulder conditions.
- The questions were administered to a population of individuals with normally function of their shoulders and without sonographic evidence of cuff pathology. These individuals consistently had the ability to perform at least 10 of the twelve questions.
Simplicity for Self-Administration:
- The questions were crafted to be easy for patients to understand and answer without requiring significant medical interpretation. This ensures that the SST is accessible and practical in busy clinical settings.
Binary Response Format:
- Each question requires a simple "yes" or "no" response, reflecting whether the patient can or cannot perform the activity. This format was chosen to streamline data collection and interpretation.
Validation Process:
- The SST was subjected to a rigorous validation process to ensure reliability and consistency in measuring shoulder function. The questions were refined based on patient feedback and expert reviews to ensure relevance and clarity.
- It was tested across various patient groups with different shoulder pathologies, confirming its utility in diverse clinical scenarios.
Focus on Outcomes:
- The SST emphasizes patient-reported outcomes rather than objective clinical measurements alone. This aligns with a growing emphasis on understanding how conditions affect patients’ lives and activities.

By centering the questions on common functional tasks, the SST allows healthcare providers to gauge the practical impact of shoulder problems and the effectiveness of interventions over time.

By focusing on functional activities that matter to patients, the SST provides a practical, patient-centered measure of shoulder function.

You can support cutting edge shoulder research that is leading to better care for patients with shoulder problems, click on this link

Follow on twitter/X: https://x.com/RickMatsen
Follow on facebook: https://www.facebook.com/shoulder.arthritis
Follow on LinkedIn: https://www.linkedin.com/in/rick-matsen-88b1a8133/

Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link)
Shoulder rehabilitation exercises (see this link).

Sunday, January 5, 2025

Stemless humeral component - is stress shielding an issue?

Every type and design of humeral component changes the way in which load is transferred from the articular surface to the bone. Thus, adaptive changes (read: "stress shielding) are inevitable.

The authors of Stress shielding following stemless anatomic total shoulder arthroplasty set out to assess the radiographic proximal humeral bone adaptations seen following stemless anatomic total shoulder arthroplasty. They prospectively followed 152 stemless total shoulder arthroplasties utilizing a single implant design performed by 21 shoulder arthroplasty surgeons.

At 2 years postoperatively, "stress shielding" was noted in 61 (41%) shoulders. A total of 11 (7%) shoulders demonstrated major stress shielding with 6 occurring along the medial calcar. At the final follow-up, no humeral implants were radiographically loose or migrated. There was no statistically significant difference in clinical and functional outcomes between shoulders with and without stress shielding. Thus the clinical importance of these adaptive changes was not demonstrated.

In reviewing some of the figures from this article, "stress shielding" may not be the principal cause of bone resorption (yellow arrow). Consider this comparison of the 3 month (left) and the 2 year (right) anterior posterior views of the same shoulder. The 2 year film was interpreted as "demonstrating severe stress shielding along the medial calcar". Note, however that the cement originally beneath the glenoid component (green arrow) is no longer seen on the 2 year film and that the two year film appears to show shift of the glenoid component's position and lucencies around the pegs (red arrow). These findings bring up the possibility of particulate debris as a contributing factor to the humeral bone resorption at the yellow arrow.

Another figure (below) shows sequential axillary radiographs (L to R: 6 weeks, 6 months, 12 months, and 24 months postoperatively) and was interpreted as showing moderate stress shielding along the medial calcar and greater tuberosity regions. However, it appears that that the proximal humeral bone may have been cystic (yellow arrow) leading to what may be humeral component loosening (red arrows).

Thus it is difficult to know whether the changes seen in the humeral bone are a result of "stress shielding" or are a result of problems with humeral and glenoid component fixation, such as those shown below in other figures from this paper.

While the authors described that "Glenoid radiolucent lines were noted in 28 (18%) patients. These were Lazarus grade 1 in 6, grade 2 in 5, grade 3 in 13, and grade 4 in 2", the relationship of these findings to humeral adaptive changes was not reported.

These authors concluded "the occurrence and severity of bony adaptations had no effect on short-term patient clinical outcomes."

For more detail on this topic see Stemless humeral components: stress shielding

Saturday, January 4, 2025

Stemless humeral arthroplasty - the head cut

Here are some thoughts about the head cut for stemless humeral arthroplasty (for either ream and run or anatomic total shoulder). Credit to Jon Yamaguchi and Kevin Khoo, UW residents par excellence, for their collaboration and work on the figures shown here.

With a bit of experience, the humeral component can be positioned optimally, without concern about the influence of a stem (short or standard length). The humeral component positioning is not dependent on CT scans or 3D preoperative planning. Instead I like to emphasize the importance of handcraft.

The head cut is the key: 135 degrees with the long axis of the shaft, 30 degrees of retroversion, resecting the maximal amount of neck while protecting the cuff and long head of biceps superiorly and the cuff posteriorly.

Excellent exposure is essential. The anterior and inferior osteophytes are vigorously resected. The "Hinge point" is the superior margin of the humeral articular surface, identified just inside the long head tendon of the biceps (which is preserved) and the supraspinatus. The capsular reflection is revealed after the osteophytes have been removed. The plane of the cuff is shown as the yellow line connecting the hinge point and the inferior capsular reflection; it is oriented at an angle of 135 degrees with the humeral shaft. The surgeon must stand tall so that she or he has the "Birds Eye View" of the posterior rotator cuff to assure that the saw passes just anterior to the infraspinatus insertion.