CT scans and their radiation risk

There is currently great enthusiasm for using computer tomographic (CT) scans to create detailed images of the arthritic shoulder. While CT scans may be necessary in unusually complex cases, we find that for the great majority of patients having surgery for shoulder arthritis a standard set of x-rays including the axillary "truth" view provides all the needed information as pointed out in this link.

Here are some examples of the preoperative anatomy of some arthritic shoulders as seen on standardized axillary views

and some preoperative and postoperative comparisons of standardized axillary views, showing the restoration of the desired anatomic relationships in a shoulder with severe arthritis.

Two recent articles that have discussed the potential risks associated with radiation prompted this blog post:

An Estimation of Lifetime Fatal Carcinogenesis Risk Attributable to Radiation Exposure in the First Year Following Polytrauma A Major Trauma Center’s Experience Over 10 Years

These authors point out that the utilization of medical imaging continues to rise, including routine use in major trauma centers. Their aims  were to estimate the amount of radiation exposure from radiographic imaging and the associated fatal carcinogenesis risk among patients treated for polytrauma at 1 institution. 2,394 patients, with a mean injury severity score of 29 were included in their analysis. The mean total radiation dose received was 30.45 mSv and the median dose was 18.46 mSv. One hundred and fifteen patients received >100 mSv of radiation. The total patient group had a 3.56% mean risk of fatal carcinogenesis of any type that related solely to medical exposure of radiation as a result of their injuries. In their lifetime, 85 patients would be expected to develop cancer as a result of medical imaging that they had undergone in the year following their accident. They caution that this study does not provide an actuarial analysis: it is unknown how many patients in the study actually went on to develop cancer.

and How Can We Reduce Cancer Risk Due to Medical Imaging?

We also note a quote from the well-known book The Gene: An Intimate History: In 1926 Herman Muller "exposed a cohort of flies to an even lower dose of radiation...Even a cursory look confirmed a striking result: the newly born flies had accumulated mutations -- dozens of them, perhaps hundreds." (page 115). 

In Radiation Exposure from Musculoskeletal Computerized Tomographic Scans the authors point out that the radiation dose from a shoulder CT scan exceeds that of 25 chest x-rays.

Where does all this leave shoulder patients and shoulder surgeons? First we need to recognize that x-rays and particularly CT scans subject the body to ionizing radiation which can increase the risk of mutations and cancer. Second, each CT scan subjects the patient to 26 times the radiation of a standardized axillary view. Third, it has yet to be demonstrated that patients with preoperative CT scans realize better clinical outcomes from shoulder arthroplasty than those having only the standard preoperative x-rays. Fourth, we suggest that it is reasonable to reserve the use of CT scans for the special cases of glenohumeral arthritis in which the needed information cannot be gained from standard x-rays.

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How you can support research in shoulder surgery Click on this link.

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).