Introduction The benefit of radiographs or steroid injection for idiopathic carpal tunnel syndrome (CTS) or ulnar neuropathy at the elbow (UNE) is open to debate. We assessed: (1) Radiographs ordered and injections performed at a new patient visit for patients presenting with either idiopathic CTS or UNE; (2) The estimated payment reduction if we omit these interventions; and (3) Patient age, sex, geographic region, and work status associated with radiographs or injections at a new patient visit for patients presenting with either idiopathic CTS or UNE. Materials and Methods Using a large database of commercial insurance claims, we identified patients with a new visit for either CTS ( N = 9,522), UNE ( N = 2,507), or both ( N = 962; 8.7%). We identified injections and radiographs, and estimated total payments for these interventions. We created three multivariable logistic regression models for each diagnosis to identify factors associated with the interventions. Results Nearly one third of patients had radiographs at a new patient visit (30% and 32% for idiopathic CTS and UNE, respectively). Nearly 10% of patients with CTS and 2.6% with UNE received an injection. Both radiographs and injections representing annual minimum payments of over $345,000 and $294,000, respectively. Among people with CTS, radiographs were independently more common in the South and less common in the West. Injection for CTS was associated with younger age; North, Central, and South regions; and retired employment status. For people with UNE, radiographs were independently associated with younger age; South or West region; and retired or working employment status. Injection for UNE was associated with retired employment status. Conclusion The prevalence of radiographs and injections suggests opportunities for savings, which might benefit clinicians with bundled or capitated payments and patients with large copayments or deductibles. The observed variation may reflect debate about whether these interventions are worthwhile. Level of Evidence Diagnostic; Retrospective Database Level III study.