UW Shoulder and Elbow Academy: Is pain and function worse for shoulders with more severe arthritis?

Radiographic Severity May Not be Associated with Pain and Function in Glenohumeral Arthritis

These authors asked (1) What radiographic findings are associated with worse pain and function in patients with glenohumeral osteoarthritis? (2) What demographic factors are associated with worse pain and function in patients with glenohumeral osteoarthritis? They conducted a retrospective study that included 3133 patients presenting for an initial office visit for primary glenohumeral osteoarthritis.

59% (1860) had assessments of patient assessed shoulder comfort and function; 48% (893) of those had radiographs. 42% (378) of those with radiographs were excluded because of other shoulder findings, recent injection, prior surgery, or inadequate radiographs, leaving 16% (515 of 3133) who were fully analyzed in this study.

The radiographic analysis included the joint space width, posterior humeral head subluxation, inferior humeral head osteophyte size, cystic change, and head asphericity.

The arthritis was classified according to the Walch, Samilson-Prieto, and Kellgren-Lawrence classifications by two separate reviewers.

Radiographic and demographic criteria as well as the presence of psychologic or mental illness were correlated with VAS Pain,, American Shoulder and Elbow Surgeons, Single Assessment Numeric Evaluation, and Simple Shoulder Test scores using univariate and multivariable regression analyses.

After accounting for age, gender, and psychologic illness in the multivariable analysis, shoulders with worse arthritis (Samilson-Prieto Grade 4 arthrosis) had lower VAS Pain scores than those with less severearthritis (Grade 0 or 1). Otherwise, the authors found no clinically important associations were found between Samilson-Prieto Grade 4, Kellgren-Lawrence Grade 3, radiographic joint space, posterior subluxation, and glenoid type; in other words, the functional levels of patients with glenohumeral arthritis did not parallel radiographic severity.

Below is a table showing the multivariate results for the SST.

Below is a table showing the results for glenoid type.

Comment: The findings of this paper are most interesting and challenge the concept that shoulders with worse arthritis would have more pain and functional loss. This result is consistent with that reported in Prearthroplasty glenohumeral pathoanatomy and its relationship to patient's sex, age, diagnosis, and self-assessed shoulder comfort and function:Shoulders with glenoid types B1 and B2 and those with more decentering did not have worse self-assessed shoulder comfort and function than the radiographically less involved A1 types.

This leads us to some important questions:

What is the best treatment for a patient with severe pain and minimal arthritic changes on radiographs?

Does the surgeon need to extend the workup to assure that the pain is coming from the glenohumeral joint and not from other sources? Does the patient have a low pain threshold that may portend a painful arthroplasty? What is the likely outcome for the patient having an arthroplasty for radiographically mild arthritis (note that in some series the postarthroplasty functional outcomes for A1 glenoids are not better than, if as good as, those for B2 glenoids - see Anatomic Total Shoulder Arthroplasty with All-Polyethylene Glenoid Component for Primary Osteoarthritis with Glenoid Deficiencies.

It seems that the surgeon and patient can be most confident in the outcome when the pain and degree of functional loss match up with the degree of radiographic involvement.