Innovation, Royalties, and Introduction of the Patent Hirsch Index within U.S. Academic Neurosurgery

Historically, practicing neurosurgeons have been key drivers of neurosurgical innovation. We sought to describe the patents held by U.S. academic neurosurgeons and to explore the relationship between patents and royalties received.

The Centers for Medicare and Medicaid CMS Open Payments Data was used to identify academic neurosurgeons who had received royalties and royalty amounts during a 5-year period (2013-2017). Online patent databases were used to gather patent details. Patent citations and 5-year individual and departmental patent Hirsch (h)-indexes were calculated. Royalties were correlated with the number of patents, patent citations, and patent h-index.

We found that 119 academic neurosurgeons (7.8%) from 57 U.S. teaching programs (48.3%) had received royalty payments; 72 (60.5%) had published 648 patents. All surgeons were men, with approximately one half in the "late" stages of their career (45.3%) and subspecializing in spinal surgery (50.4%). The patented products or devices were most commonly used for spinal surgery (72.1%), with 2010-2019 the most productive period (n = 455; 70.2%). The median number of citations per patent was 32 (range, 0-620), with 33% having ≥100 citations. The highest individual and institutional patent h-index was 95; 25 (34.7%) neurosurgeons had a patent h-index of ≥5. The median total royalty payment per individual neurosurgeon was $111,011 (range, $58.05-$76,715,750.34). Royalties were correlated with the number of patents (Spearman r = 0.37; P ≤ 0.001), citations (Spearman r, 0.38; P ≤ 0.001), and inventor h-index (Spearman r = 0.38; P ≤ 0.001).

Few U.S. academic neurosurgeons (7.8%) receive royalties and hold patents (4.7%), with an even smaller select group having a patent h-index of ≥5 (1.6%).