Proximal Femur Replacements for an Oncologic Indication Offer a Durable Endoprosthetic Reconstruction Option: A 40-year Experience.

BACKGROUND: Proximal femur replacements (PFRs) are an effective surgical option to treat primary and metastatic tumors causing large bony defects in the proximal femur. Given the relative rarity of these indications, current studies on PFR for oncologic indications are generally limited by patient volume or relatively short-term follow-up. Because recent advances in systemic therapy have improved the prognosis of patients who undergo limb salvage surgery for musculoskeletal tumors, data on the long-term durability of endoprosthetic reconstructions have become increasingly important. QUESTIONS/PURPOSES: (1) How does the long-term survival of cemented bipolar PFRs compare with patient survival in patients who underwent PFR for benign, aggressive, and metastatic tumors? (2) What are common reasons for revisions of primary PFRs? (3) Which factors are associated with survival of primary PFRs? (4) What is the survivorship free from conversion of bipolar PFRs to THA? METHODS: Between January 1, 1980, and December 31, 2020, we treated 812 patients with an endoprosthetic reconstruction for an oncologic indication. All patients who underwent a primary PFR for an oncologic indication were included in this study. The study cohort consisted of 122 patients receiving a primary PFR. Eighteen patients did not reach a censored endpoint such as death, revision, or amputation within 2 years. Thirty-three patients died within 2 years of their surgery. Of the 122 patients with primary PFRs, 39 did not reach a censored endpoint and have not been seen within the past 5 years. However, the mean follow-up time for these patients was longer than 10 years. The Social Security Death Index was queried to identify any patients who may have died but might not have been captured by our database To allow for adequate follow-up, endoprosthetic reconstructions performed after December 31, 2020 were excluded. The mean age at the time of the index surgery was 48 ± 22 years. The mean follow-up time of surviving patients was 7 ± 8 years. All PFRs were performed using a bipolar hemiarthroplasty with a cemented stem, and all implants were considered comparable. Demographic, oncologic, procedural, and outcome data including prosthesis survival, patient survival, complication rates, and rates of conversion to THA were analyzed. Patient, prosthesis, and limb salvage survival rates were generated, with implant revision as the endpoint and death as a competing risk. Statistical significance was defined as p < 0.05. RESULTS: Generally, patients with benign or low-grade (Stage I) disease outlived their implants (100% patient survival through 30 years; p = 0.02), whereas the opposite was true in patients with high-grade, localized Stage II disease (64% patient survival at 5 years [95% CI 49% to 76%]; p = 0.001) or widespread Stage III metastatic disease (6.2% patient survival at 5 years [95% CI 0.5% to 24%]; p < 0.001). Primary PFR implant survival at 5, 10, 20, and 30 years was 97% (95% CI 90% to 99%), 81% (95% CI 67% to 90%), 69% (95% CI 46% to 84%), and 51% (95% CI 24% to 73%), respectively. Eight percent (10 of 122) of primary PFRs were revised for any reason. The most common causes of revision were aseptic loosening (3% [four of 122]), infection (3% [three of 122]), breakage of the implant (2% [two of 122]), and tumor progression (1% [one of 122]). Follow-up time was the only factor that was associated with revision of primary PFRs. Neither segment length nor stem length were associated with revision of primary. Six percent (seven of 122) of PFRs were converted to THA at a mean 15 ± 8 years from the index procedure. Survivorship free from conversion to THA (accounting for death as a competing risk) was 94% (95% CI 85% to 99%), 86% (95% CI 68% to 94%). and 77% (95% CI 51% to 91%) at 10, 20, and 30 years, respectively. CONCLUSION: Cemented bipolar PFRs for an oncologic indication are a relatively durable reconstruction technique. Given the relative longevity and efficacy of PFRs demonstrated in our study, especially in patients with high-grade or metastatic disease where implant survival until all-cause revision was longer than patient survival, surgeons should continue to seriously consider PFRs in appropriate patients. The relative rarity of these reconstructions limits the number of patients in this study as well as in current research; thus, further multi-institutional collaborations are needed to provide the most accurate prognostic data for our patients. LEVEL OF EVIDENCE: Level III, therapeutic study.

Preoperative Vitamin D Repletion in Total Knee Arthroplasty: A Cost-Effectiveness Model.

BACKGROUND: Recent studies have identified vitamin D deficiency (serum 25-hydroxyvitamin D [25(OH)D] < 20 ng/L) as a potentially modifiable risk factor for prosthetic joint infection (PJI) in arthroplasty. The purpose of this study is to determine whether implementation of preoperative 25(OH)D repletion is cost-effective for reducing PJI following total knee arthroplasty (TKA). METHODS: A cost estimation predictive model was generated to determine the utility of both selective and nonselective 25(OH)D repletion in primary TKA to prevent PJI. Input data on the incidence of 25(OH)D deficiency, relative complication rates, and costs of serum 25(OH)D repletion and 2-stage revision for PJI were derived from previously published literature identified using systematic review and publicly available data from Medicare reimbursement schedules. Mean, lower, and upper bounds of 1-year cost savings were computed for nonselective and selective repletion relative to no repletion. RESULTS: Selective preoperative 25(OH)D screening and repletion were projected to result in $1,504,857 (range, $215,084-$4,256,388) in cost savings per 10,000 cases. Nonselective 25(OH)D repletion was projected to result in $1,906,077 (range, $616,304-$4,657,608) in cost savings per 10,000 cases. With univariate adjustment, nonselective repletion is projected to be cost-effective in scenarios where revision for PJI costs ≥$10,636, incidence of deficiency is ≥1.1%, and when repletion has a relative risk reduction ≥4.2%. CONCLUSION: This predictive model supports the potential role of 25(OH)D repletion as a cost-effective mechanism of reducing PJI risk in TKA. Given the low cost of 25(OH)D repletion relative to serum laboratory testing, nonselective repletion appears to be more cost-effective than selective repletion. Further prospective investigation to assess this modifiable risk factor is warranted.

Academic Influence and Its Relationship to Industry Payments in Orthopaedic Surgery.

BACKGROUND: The Hirsch index (h-index) quantifies research publication productivity for an individual, and has widely been considered a valuable measure of academic influence. In 2010, the Physician Payments Sunshine Act (PPSA) was introduced as a way to increase transparency regarding U.S. physician-industry relationships. The purpose of this study was to investigate the relationship between industry payments and academic influence as measured by the h-index and number of publications among orthopaedic surgeons. We also examined the relationship of the h-index to National Institutes of Health (NIH) funding. METHODS: The h-indices of faculty members at academic orthopaedic surgery residency programs were obtained using the Scopus database. The PPSA web site was used to abstract their 2014 industry payments. NIH funding data were obtained from the NIH web site. Mann-Whitney U testing and Spearman correlations were used to explore the relationships. RESULTS: Of 3,501 surgeons, 78.3% received nonresearch payments, 9.2% received research payments, and 0.9% received NIH support. Nonresearch payments ranged from $6 to $4,538,501, whereas research payments ranged from $16 to $517,007. Surgeons receiving NIH or industry research funding had a significantly higher mean h-index and number of publications than those not receiving such funding. Surgeons receiving nonresearch industry payments had a slightly higher mean h-index and number of publications than those not receiving these kinds of payments. Both the h-index and the number of publications had weak positive correlations with industry nonresearch payment amount, industry research payment amount, and total number of industry payments. CONCLUSIONS: There are large differences in industry payment size and distribution among academic surgeons. The small percentage of academic surgeons who receive industry research support or NIH funding tend to have higher h-indices. For the overall population of orthopaedic surgery faculty, the h-index correlates poorly with the dollar amount and the total number of industry research payments. Regarding nonresearch industry payments, the h-index also appears to correlate poorly with the number and the dollar amount of payments. These results are encouraging because they suggest that industry bias may play a smaller role in the orthopaedic literature than previously thought.

The Relationship Between OREF Grants and Future NIH Funding Success.

BACKGROUND: The Orthopaedic Research and Education Foundation (OREF) is the leading specialty-specific nongovernmental organization providing orthopaedic funding in the United States. As extramural research funding has become increasingly difficult to acquire, one mission of the OREF is to support investigators to generate data needed to secure larger extramural funding from agencies such as the National Institutes of Health (NIH). The objectives of this study were to evaluate the rate of translating OREF faculty-level grants into subsequent NIH funding and to determine if there are identifiable factors that increase the rate of converting an OREF grant into NIH funding. METHODS: This is a retrospective review of OREF grants awarded to full-time faculty orthopaedic surgeons between 1994 and 2014. Grants were analyzed on the basis of award type and were categorized as basic science, clinical, or epidemiological. Sex, individual scholarly productivity, and publication experience were evaluated. All awardees were assessed for subsequent NIH funding using the NIH RePORTER web site. RESULTS: One hundred and twenty-six faculty-level OREF grants were awarded to 121 individuals. Twenty-seven OREF grant awardees (22%) received NIH funding at a mean of 6.3 years after OREF funding. Nineteen (46%) of 41 Career Development Grant winners later received NIH funding compared with 10 (12%) of 85 other award winners. OREF grants for basic science projects were awarded more often (58%) and were more than 4 times as likely to result in NIH funding than non-basic science projects (odds ratio, 4.70 [95% confidence interval, 1.66 to 13.33]; p = 0.0036). Faculty who later received NIH funding had higher scholarly productivity and publication experience (p < 0.05). CONCLUSIONS: The OREF grant awardee conversion rate of 22% and, particularly, the 46% for Career Development Grant winners compares favorably with the overall NIH funding success rate (18% in 2014). Faculty-level OREF grants appear to achieve their purpose of identifying and supporting researchers who aim to secure subsequent federal funding. CLINICAL RELEVANCE: The goal of this study is to examine how successful faculty who have obtained OREF grants have been in securing NIH funding later in their careers. Although subsequent accrual of NIH funding is not the only goal of OREF funding, it can be used as an important benchmark to assess the development of orthopaedic clinician-scientists.

The role of chairman and research director in influencing scholarly productivity and research funding in academic orthopaedic surgery.

The purpose of this study was to determine what orthopaedic surgery department leadership characteristics are most closely correlated with securing NIH funding and increasing scholarly productivity. Scopus database was used to identify number of publications/h-index for 4,328 faculty, department chairs (DC), and research directors (RD), listed on departmental websites from 138 academic orthopaedic departments in the United States. NIH funding data was obtained for the 2013 fiscal year. While all programs had a DC, only 46% had a RD. Of $54,925,833 in NIH funding allocated to orthopaedic surgery faculty in 2013, 3% of faculty and 31% of departments were funded. 16% of funded institutions had a funded DC whereas 65% had a funded RD. Department productivity and funding were highly correlated to leadership productivity and funding(p< 0.05). Mean funding was $1,700,000 for departments with a NIH-funded RD, $104,000 for departments with an unfunded RD, and $72,000 for departments with no RD. These findings suggest that orthopaedic department academic success is directly associated with scholarly productivity and funding of both DC and RD. The findings further highlight the correlation between a funded RD and a well-funded department. This does not hold for an unfunded RD.