The expansion of age-related degenerative spine pathologies has led to increased referrals to spine surgeons. However, the majority of patients referred for surgical consultation do not need surgery, leading to inefficient use of healthcare resources. This study aims to elucidate preoperative patient variables that are predictive of patients being offered spine surgery.

We conducted an observational cohort study on patients referred to our institution between May 2013 and January 2015. Patients completed a detailed preclinic questionnaire on items such as history of presenting illness, quality-of-life questionnaires, and past medical history. The primary end point was whether surgery was offered. A multivariable logistical regression using the random forest method was used to determine the odds of being offered surgery based on preoperative patient variables.

An analysis of 1194 patients found that preoperative patient variables that reduced the odds of surgery being offered include mild pain (odds ratio [OR] 0.37, p=0.008), normal walking distance (OR 0.51, p=0.007), and normal sitting tolerance (OR 0.58, p=0.01). Factors that increased the odds of surgery include radiculopathy (OR 2.0, p=0.001), patient’s belief that they should have surgery (OR 1.9, p=0.003), walking distance <50 ft (OR 1.9, p=0.01), relief of symptoms when bending forward (OR 1.7, p=0.008) and sitting (OR 1.6, p=0.009), works more slowly (OR 1.6 p=0.01), aggravation of symptoms by Valsalva (OR 1.4, p=0.03), and pain affecting sitting/standing (OR 1.1, p=0.001).

We identified 11 preoperative variables that were predictive of whether patients were offered surgery, which are important factors to consider when screening outpatient spine referrals.