Percutaneous epiphysiodesis using transphyseal screws (PETS) versus tension-band plating (TBP): comparative study of outcomes for correcting limb length discrepancy

OBJECTIVES

The best effective treatment strategy for limb length discrepancy (LLD) is still being debated. The goal of this study was to compare the efficacy and results of tension-band plating (TBP) and percutaneous epiphysiodesis using transphyseal screws (PETS) for LLD correction.

METHODS

From June 2008 to January 2019, children who had lower extremity epiphysiodesis with either TBP or PETS were reviewed retrospectively. At the conclusion of treatment, LLD, angular deformity, and complications were reviewed. The t-test or Wilcoxon rank sum test was used to compare continuous variables. Categorical variables were evaluated using Fisher's exact test or χ² test.

RESULTS

A total of 32 epiphysiodeses with TBP (14 patients, 24 femur/tibias) or PETS (13 patients, 23 femur/tibias) were compared. TBPs were conducted while the patients were younger (11.0 vs. 13.1 years, p = 0.005). The treatment durations were similar in both groups (TBP: 23.5 months vs. PETS: 24 months, p = 0.132). PETS had significantly shorter operative time (p = 0.047), length of hospital stay (p = 0.014), and time to return to full activity (p = 0.043). LLD in the TBP group reduced from 2.64 to 1.38 cm (p = 0.005), while in the PETS group it decreased from 2.76 to 1.08 cm (p = 0.001). During treatment, the rate of LLD correction was 0.49 ± 0.9 cm/year for limbs treated with TBP and 1.0 ± 1.1 cm/year for limbs treated with PETS (p = 0.185). At the end of treatment, 8 TBP cases (47%) and 9 PETS cases (60%) had achieved LLD ≤ 2 cm (p = 0.502), and at the most recent follow-up, this had grown to 11 (65%) in the TBP group and 12 (80%) in the PETS group. There were no significant differences in the total number of complications between groups (p > 0.05). Revision surgery was required in 11 TBP and 3 PETS limbs due to persistent LLD or angular deformity (AD) (p = 0.016). Logistic regression did not reveal any significant association between TBP and the rate of complication or revision surgery.

CONCLUSION

PETS and TBP are both effective methods for limb length equalization. PETS, on the other hand, was linked to a shorter operative time, a shorter hospital stay, a faster recovery to pre-operative function, and a lower complication rate. The rate of revision surgery due to persistent LLD or AD was higher in TBP. We advise surgeons against utilizing TBP to correct LLD.

LEVEL OF EVIDENCE

III.

Rebound predictors of varus-valgus deformities around the knee corrected by guided growth

PURPOSE

Coronal plane deformities around the knee are rather common condition in children. Guided growth by temporary hemiepiphysiodesis is considered to be the preferred primary treatment in many cases. Despite the popularity of hemiepiphysiodesis, the incidence of recurrence of deformity and predictors for rebound are not well defined. The objectives of this study were to determine the incidence of the recurrence of varus-valgus deformities around the knee treated by temporary hemiepiphysiodesis and possible predictors for the rebound.

METHODS

We retrospectively reviewed medical records and x-ray images of 130 patients with varus-valgus deformities around the knee treated by tension-band (eight-plate) hemiepiphysiodesis, between the years 2006 and 2016 in our institution. The incidence of rebound of varus-valgus deformities around the knee and possible predictors were analyzed.

RESULTS

Rebound of the deformity was observed in 10% of patients. Risk factors found to be in correlation with recurrence include young age, deformity of proximal tibia, proximal tibial medial growth plate beaking, and comorbidities (like metabolic disorders, multiple hereditary exostoses and genetic syndromes).

CONCLUSION

The results of this study show that there is a noteworthy incidence of rebound in patients treated by temporary hemiepiphysiodesis for coronal deformities around the knee. The risk factors are also outlined. These patients, especially the ones with risk factors, require close surveillance until maturity.

LEVEL OF EVIDENCE

Level III-Case control study.