Diabetes, HbA1c, infection, and shoulder arthroplasty

Association of Perioperative Glycemic Control With Deep Postoperative Infection After Shoulder Arthroplasty in Patients With Diabetes (J Am Acad Orthop Surg 2018;0:1-8)

These authors queried the  PearlDiver Patient Records Databasefor patients with diabetes who underwent primary shoulder arthroplasty. They assessed the incidence of wound complications within 6 months within 1 year for each perioperative HbA1c level. 

Patients with DM had higher rates of wound complications (1.4% versus 0.9%; odds ratio, 1.22; P = 0.028) and deep infection (0.7% versus 0.4%; odds ratio, 1.47; P = 0.001). 

The rates of wound complications (P = 0.0008) and deep postoperative infection (P = 0.002) increased markedly as the perioperative HbA1c level increased. 

Comment: As the authors point out, the literature on the effects of preoperative optimization of HbA1c values and postoperative infection is lacking. Thus, while it seems compelling to do so, we cannot be sure that requiring our diabetic patients to 'get their HbA1c below 8' will lower their risk of infection.

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The risks associated with total shoulder in patients with diabetes and others

The impact of insulin dependence on short-term postoperative complications in diabetic patients undergoing total shoulder arthroplasty

These authors sought to determine the impact of insulin dependence on the risk profile of diabetic patients having shoulder arthroplasty. Patients were categorized as non–diabetes mellitus (non-DM), non–insulin dependent diabetes mellitus (NIDDM), or insulin-dependent diabetes mellitus (IDDM). 

In bivariate analysis, NIDDM and IDDM were associated with multiple postoperative complications, including stroke, sepsis, wound complications, blood transfusion, and extended LOS. With multivariable logistic regression, however, NIDDM patients did not have significantly greater odds of any study end point relative to non-DM patients. IDDM patients had significantly greater odds for having any postoperative complication (odds ratio [OR], 1.53), stroke (OR, 13.63), blood transfusion (OR, 1.67), and extended LOS (OR, 1.38).

They concluded that after adjustment for demographics and comorbidity burden, NIDDM patients had risk profiles similar to those of non-DM patients. IDDM was an independent predictor of multiple postoperative complications. 

Comment: While the authors did not have HbA1c levels on the patients in this study, they state that "insulin dependence appears to be a more robust risk factor than glycemic control as measured by the HbA1c level." There is currently a re-examination of the value of using oft-quoted target of an HbA1c level of 7. There is some evidence that (1) some patients may not be able to reach this goal and (2) 'forcing' an HbA1c level of 7 may not be safe for the patient. There seems to be a trend toward accepting the more reachable and perhaps safer target of 8. 

It remains unclear to us how much the well-documented increased risk of surgery in patients with IDDM can be modified. The table above demonstrates that a number of important health factors are co-variates with the severity of diabetes making it a challenge to sort the effect of one from the other. 

At minimum, our responsibility is to inform our patients of the potential risk of surgery. One approach is to use the American College of Surgeons' Surgical risk calculator

Interestingly this calculator classes diabetes as "none", "oral", "insulin".

The reader may like to enter "23472 - Arthroplasty, glenohumeral joint; total shoulder (glenoid and proximal humeral replacement (eg, total shoulder))" into the procedure box at the top and calculate his/her estimated risk.

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Information about shoulder exercises can be found at this link.

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You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'

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Shoulder stiffness and glucose control

The relationship between the incidence of adhesive capsulitis and hemoglobin A1c

These authors determined a "cumulative" HbA1c, that uses HbA1c values over time to estimate the total disease burden that the patient experiences over a period. They evaluated whether a correlation existed between cumulative HbA1c levels in diabetic patients and the prevalence of frozen shoulder using a retrospective review of  patients from a single institution for which HbA1c values were available. The exclusion criteria were age younger than 18 years, HbA1c levels greater than 15, and patients who had 1 year or less of single or consecutively recorded HbA1c levels. A total of 24,417 patients met the inclusion criteria.

They found that cumulative HbA1c was positively associated with adhesive capsulitis.  The effect size of cumulative HbA1c on adhesive capsulitis was significant; for each unit of time that the HbA1c level was greater than 7, there was a 2.77% increase in the risk of adhesive capsulitis.

Comment: The mechanism of joint stiffness in individuals with abnormal sugar metabolism is thought to be non-enzymatic gycosylation, causing abnormal cross links between collagen fibers resulting in increased stiffness. 

Surgeons performing surgical releases for stiff diabetic shoulders often note increased thickness and toughness of the capsular tissue. Surgeons attempting to manage diabetic stiff shoulders with manipulation are often frustrated for the same reason.

This paper would have been stronger if the authors had provided the diagnostic criteria used for making the diagnosis of adhesive capsulitis (if indeed these criteria were standardized across the practice) and if they had performed a multivariate analysis that included all the data they collected: patient age, sex, BMI, length of time over which the HbA1c data were collected (range, 12-207 months), thyroid status, and insulin dosage at the time of diagnosis. 

In any event, this study reminds us that, in addition to its effect on surgical complications, glycemic control may affect the success of procedures designed to improve shoulder motion, including shoulder arthroplasty. 

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Consultation for those who live a distance away from Seattle.

Click here to see the new Shoulder Arthritis Book.

Click here to see the new Rotator Cuff Book

Information about shoulder exercises can be found at this link.

Use the "Search" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'

See from which cities our patients come.

See the countries from which our readers come on this post.