Follow-Up After Hemiepiphysiodesis: Can We Do Better?

Abstract

Background: Hemiepiphysiodesis carries a risk of overcorrection, especially if the patient demonstrates poor follow-up. Few studies have evaluated patients treated with hemiepiphysiodesis for risk factors predictive of follow-up. The present study evaluates patients who underwent hemiepiphysiodesis at the knee and/or ankle for associations between late follow-up (LFU), lost to follow-up (LTFU), and sociodemographic factors, such as area deprivation index (ADI), race, ethnicity, insurance status, age, sex, and BMI.

Methods: Skeletally immature patients undergoing hemiepiphysiodesis from 2018 to 2022 for coronal deformities of the knee and ankle were retrospectively studied through electronic medical record. Follow-up status was categorized as on-time follow-up (OTFU), LFU, or LTFU. Late presentation was defined as presentation over 6 months past the recommended follow-up date. The angle between the mechanical axis of the femur and the tibia and the lateral distal tibial angle were measured preoperatively and at final follow-up for coronal knee deformities and ankle valgus, respectively. Overcorrection was stratified by severity: 0° to 5° was considered acceptable, 5° to 10° mild, 10° to 15° moderate, and >15° severe. OTFU was used as a reference for statistical comparisons of follow-up status. Statistical comparisons were performed with multivariate analysis.

Results: One hundred fifty-five patients were included, 91 male and 64 female. In all, 103 patients followed up on-time, 28 were LFU (mean 17.9 mo after recommended follow-up), and 24 (average 6.5 mo from surgery) were LTFU. Of the LFU, 4 underwent an additional procedure to correct new deformity. Of the LFU genu valgum limbs, 50.0% were severely overcorrected. Of the LFU genu varum limbs, 38.5% were severely overcorrected. ADI (national), male, black race, and uninsured status were significantly more likely to be LTFU. The predominant deformity in both the LFU and LTFU groups was genu varum and the predominant diagnosis was Blount disease.

Conclusion: Poor follow-up after hemiepiphysiodesis can result in overcorrection necessitating additional procedures. Factors associated with LFU included a diagnosis of genu varum. Factors associated with LTFU included older age, high national ADI, increased weight for age percentile, male, black race, uninsured status, and genu varum. Quality improvement measures should be implemented to ensure follow-up in high-risk groups.

Level of evidence: Level IV.