A Small Number of Surgeons Perform the Large Majority of Uncommon Nerve Decompression Procedures.

Background: Notable surgeon-to-surgeon variation in rates of uncommon surgery can reflect appropriate concentration of expertise with technically difficult or risky procedures that address problematic impairment due to objective pathophysiology. Examples include vascularized tissue transfer or transplantation to address complex tissue loss and release of bony elbow ankylosis. Perhaps more problematic is notable variation in straightforward, discretionary surgeries intended to alleviate pain, offered in the absence of objectively measurable pathophysiology, and without experimental evidence of benefit over placebo and other nonspecific effects. Evidence of concentration of this type of surgery in the hands of a few surgeons might point to inordinate influence of surgeon opinions on patient behavior. A study of variation in operations for upper extremity peripheral mononeuropathy has the potential to uncover potentially problematic variation. There are billing codes specific to common surgeries that can benefit patients with objectively verifiable neuropathies. And there are billing codes that represent less common nerve decompression surgeries that in many cases are offered in the absence of both objective evidence of pathophysiology as well as experimental evidence that surgery alleviates pain better than simulated surgery.

Questions/purposes: We asked the following questions: (1) Among surgeons who billed a mean of at least 10 carpal tunnel releases (CTRs) per year in patients with Medicare insurance in the United States, how many also performed at least one less common peripheral nerve release and cubital tunnel release (CubTR) per year? (2) Among surgeons who billed a mean of at least one less common peripheral nerve release or CubTR on average per year, what is the median and range of the number of less common peripheral nerve releases and CubTRs and the relative proportion of these compared with CTRs per year? (3) Are there any differences in gender, specialty, and number of CTRs and CubTRs between surgeons who performed at least one less common nerve decompression and surgeons who, on average, performed none?

Methods: Using the Medicare Physician & Other Practitioners - by Provider and Service database, we identified surgeons who perform a minimum of 10 CTRs per year. Because this database has all surgeries billed to Medicare performed in any setting by individual surgeons, it is well suited to the study of surgeon-specific operative rates among Medicare patients. Among 7259 clinicians who billed one or more nerve procedure to Medicare between January 2013 and December 2019, we excluded 120 nonsurgical clinicians, 47 podiatrists, and 1561 clinicians who billed procedures as an organization. Among the remaining 5531 surgeons, 5439 performed at least 10 CTRs on average per year, which we considered representative of surgeons who include nerve decompression surgery as a part of their practice. Among these 5439 surgeons, we calculated the mean number of CTRs, CubTRs, and less common peripheral nerve releases (including decompression of a digital nerve, nerve in hand or wrist, ulnar nerve at the wrist, brachial plexus, and unspecified nerve) per year between 2013 and 2019. Decompression of the median nerve at the carpal tunnel, the ulnar nerve at the cubital tunnel, and, much less frequently, the ulnar nerve at the wrist typically addresses measurable neuropathy. The other nerve releases are often performed for illnesses characterized by pain that are defined, in part, by the absence of experimentally verifiable pathophysiology such as radial tunnel and pronator (or lacertus) syndromes. We counted the number of surgeons who billed an average of at least one less common peripheral nerve release and CubTR per year; the median and range of the number of less common nerve releases and CubTRs and their relative proportion among those subsets of surgeons; and differences in the number of surgeons who performed one or none less common surgery by gender, specialty, and volume of CTR/CubTR surgery.

Results: Of 5439 surgeons who performed a mean of at least 10 CTRs per year, 2% (93) performed a mean of at least one less common peripheral nerve release per year among patients on Medicare, 14% (775) at least one CubTR, and 1% (47) performed both. Surgeons who performed a mean of at least one less common peripheral nerve release per year performed a median (IQR) of 7 (3 to 17) per year (with a maximum of 153 per year), representing approximately one less common peripheral nerve release for every five CTRs. Sixty-five percent (4076 of 6272) of all less common nerve procedures were performed by the top 20 billing surgeons. Gender was not associated with doing one or more uncommon nerve releases (women 1% [6 of 413], men 2% [87 of 5026]; p = 0.84), but specialty was, with plastic surgeons leading (6% [20 of 340] compared with 1% [73 of 5087] for other types of surgeons; p < 0.001).

Conclusion: The observation that a relatively small number of surgeons perform a large majority of the surgery for nerve syndromes conceptualized as accounting for arm pain suggests that most surgeons are cautious about ascribing pain to conceptual nerve compression syndromes and offering surgery.

Clinical relevance: An approach to surgical care founded on ethical principles regards this type of notable variation as a signal of inordinate influence of surgeon opinion on patient behavior, suggesting that professional conduct may be supported by safeguards such as checklists that help guide patients to choices consistent with their values unclouded by surgeon beliefs, false hope, and common misconceptions.