Shoulder arthroplasty after prior external beam radiation therapy: a matched cohort analysis

Total knee arthroplasty outcomes in patients with a history of radiation therapy

PURPOSE

There is limited information regarding how a history of cancer and related treatment with radiation therapy (RT) impacts outcomes after total knee arthroplasty (TKA). Therefore, our study assessed the risk of developing medical and surgical complications following TKA in patients with cancer as well as those with a history of prior RT.

METHODS

Within a national federated research network, we conducted a retrospective cohort study, querying for patients who underwent a primary TKA from 2002 to 2022. Amongst these patients, we identified three pairs of cohorts: (1) those with and without a history of RT, (2) those with and without a cancer history, and (3) those with a history of cancer who were treated with and without RT. Following propensity-score matching for comorbidities, surgical and medical complications within the 30-day, 90-day, and 1-year postoperative periods were assessed.

RESULTS

RT was associated with an increased risk of multiple medical complications. When controlling for cancer, patients receiving RT had lower odds of medical complications, and there was no association with these medical complications. Cancer patients had an increased risk of multiple medical complications including venous thromboembolism at all time-intervals. PJI risk was increased at 1-year among cancer patients that received RT compared to those that did not (OR: 1.5, 95% CI: 1.1-2.0).

CONCLUSIONS

While RT may not increase the risk of medical complications, a history of cancer was associated with adverse outcomes following TKA. Our findings serve to help educate this patient population and encourage collaboration with patients' oncologists during the pre-operative optimization process.

What are we matching on and why? A systematic review of matched study designs in shoulder arthroplasty

BACKGROUND

Establishing patient-matched cohorts can be a valuable technique for minimizing selection bias in outcomes research pertaining to shoulder arthroplasty. This systematic review evaluated the variety and inconsistency with which matching techniques are employed in matched studies assessing outcomes following shoulder arthroplasty.

METHODS

The PubMed, EMBASE, and Cochrane computerized databases were queried from their inception through December 2023 to identify clinical outcome studies of shoulder arthroplasty that employed a matched study design. Study quality was assessed via the Methodological Index for Non-Randomized Studies criteria. Matching techniques, covariates included, and covariate justification were aggregated.

RESULTS

Among 110 studies encompassing 483,738 shoulder arthroplasties, 82 (74.6%) studies employed direct matching and 28 (25.5%) employed propensity score matching. Seventy-four distinct covariates were used in at least one study, with 86 unique combinations of covariates employed. Studies used a median of 4 covariates (range 1-27). The most common covariates were age (94.5%), sex (89.1%), body mass index (26.4%), smoking (19.1%), and follow-up duration (19.1%). Only 16 (14.6%) studies reported justification for the covariates included.

CONCLUSIONS

There are marked methodological discrepancies among studies using covariate matching methods in the shoulder arthroplasty literature. Future matched studies in shoulder arthroplasty should provide justification for included covariates and properly account for matching in their statistical analyses to enhance the validity of study findings. When patient matching is deemed appropriate, key variables to consider for matching may include patient age, sex, comorbidity burden and, when analyzing multiple clinical conditions, surgical indication.

Impact of external beam radiation on total shoulder arthroplasty outcomes: a propensity-matched cohort study

BACKGROUND

External beam radiation therapy has a number of deleterious effects on the body, and a number of post-operative complications have been reported for several surgeries including total knee arthroplasty. However, few studies have investigated the impact of external beam radiation therapy for total shoulder arthroplasty (TSA). Our study aimed to assess the systemic and joint complications associated with TSA in patients with prior radiation exposures, as well as evaluate the surgical outcomes of radiation patients compared to non-radiation TSA patients.

MATERIALS AND METHODS

A retrospective cohort analysis was conducted using the TriNetX Analytics Network. A 1:1 propensity score matching function was utilized to create two cohorts with matched baseline characteristics within the TriNetX network. Comparisons of the primary and secondary outcomes between the two cohorts were made using odds ratios. A p value of < 0.05 was determined to be significant.

RESULTS

A total of 75,510 patients that received TSA were identified with 1505 having a history of radiation therapy (RT) and 73,605 with no radiation therapy (non-RT). After propensity matching, both groups contained 1484 patients. RT patients were at higher risk for developing prosthetic joint infection, acute renal failure, altered mental state, cerebrovascular event, DVT, PE, pneumonia, respiratory failure, and UTI compared to non-RT patients at different time points (p < 0.5).

CONCLUSION

Patients with prior history of external beam radiation undergoing TSA had a higher risk of systemic complications and prosthetic joint infection compared to patients without a prior history. These complications suggest a more complicated post-operative management course for these patients.