Introduction:

Lumbar spinal fusion (LSF) and total hip arthroplasty (THA) are commonly performed in patients who have concomitant spine and hip pathology. While patients who have three or more levels fused during LSF have increased postoperative opioid consumption after undergoing THA, it is unknown whether the number of levels fused during LSF affects THA functional outcomes.

Methods:

A retrospective study was conducted at a tertiary academic center for patients who underwent LSF first and then had a primary THA performed with a minimum of one-year follow-up for the Hip Disability and Osteoarthritis Outcome Score Joint Replacement (HOOS-JR). Operative notes were reviewed to determine the number of levels fused during LSF. There were 105 patients who underwent one-level LSF, 55 patients underwent two-level LSF, and 48 patients underwent three-or-more level LSF. No significant differences existed in age, race, body mass index, and comorbidities between the cohorts.

Results:

While preoperative HOOS-JR was similar among the three cohorts, patients who had three-or-more level LSF had significantly lower HOOS-JR scores than patients who had two-level or one-level LSF (71.4 vs. 82.4 vs. 78.2; P = 0.010) and a lower delta HOOS-JR (27.2 vs. 39.4 vs. 35.9; P = 0.014). Patients who had three-or-more level LSF had a significantly lower rate of achieving minimal clinically important difference (61.7 vs. 87.2 vs. 78.7%; P = 0.011) and the patient acceptable symptom state (37.5 vs. 69.1 vs. 59.0%; P = 0.004) for the HOOS-JR, compared to patients who had two-level or one-level LSF, respectively.

Discussion/conclusions:

Surgeons should counsel patients who have had three-or-more level LSF that they may have a lower rate of hip function improvement and symptom acceptability after THA, compared to patients who have had a fewer number of levels fused during LSF.