Low BMI Female Athletes Have Higher Revision Rate Post Surgery

Elite female athletes with low body mass index (BMI) who undergo primary hip arthroscopy are more likely to need a subsequent revision compared with same performance level female athletes with normal body mass index, according to a new study.

However, the surgeries still result in significant improvements in patient-reported outcomes and satisfactory return to play rates.

In the study, “Clinical Outcomes and Reoperation Rates After Hip Arthroscopy in Female Athletes With Low Versus Normal Body Mass Index: A Propensity-Matched Comparison With Minimum 2-Year Follow-up,” published online on November 24, 2021 in The American Journal of Sports Medicine, the researchers sought to better understand the effect of low body mass index on hip arthroscopy outcomes in female athletes.

They reported on 2-year patient-reported outcomes and return to sports and compared the results with those of a propensity-matched control group of elite female athletes with normal body mass index.

All the study participants were being treated for femoroacetabular impingement syndrome, and they were all high-level professional, collegiate, or high school female athletes who underwent hip arthroscopy between September 2009 and March 2017 at a single institution.

The researchers collected data on patient-reported outcomes including modified Harris Hip Score, Nonarthritis Hip Score, Hip Outcome Score-Sport Specific Subscale, and Visual Analog Scale for pain.

They also calculated the percentage of patients achieving the minimal clinically important difference, Patient Acceptable Symptom State, and maximum outcome improvement satisfaction threshold.

All 21 female athletes with low body mass index showed improvement for all patient-reported outcomes (p < .001), however, compared with the control group they had lower rates of achieving minimal clinically important difference for the modified Harris Hip Score (54.5% vs. 77.4%; p = .041), Patient Acceptable Symptom State for the International Hip Outcome Tool-12 (45.5% vs. 72.6%; p = .022) and maximum outcome improvement satisfaction threshold for the visual analog scale score (31.8% vs. 56.5%; p = .047).

The female athletes with low body mass index also had higher rates of revision compared with the control group (27.2% vs. 10.6%; p = .049), but the return to sports rates were similar (75.0% vs. 74.5%; p > .05).

The researchers wrote, “High-level female athletes with low BMI undergoing primary hip arthroscopy for femoroacetabular impingement syndrome demonstrated significant improvement in patient-reported outcomes and acceptable rates of return to play. When compared with a control group with normal body mass index, they exhibited higher rates of revision and lower rates of achieving minimal clinically important difference for the modified Harris Hip Score, Patient Acceptable Symptom State for the International Hip Outcome Tool-12, and maximum outcome improvement satisfaction threshold for the visual analog scale score.”