Guided growth using a tension-band plate in Blount's disease

Our observational study's objective was to determine how effective guided growth with tension-band plates was to correct the deformity in Blount's disease. We reviewed the records of 14 children (18 limbs) with Blount's disease who were treated with tension-band plates as the only surgical intervention at a single institution over eight years. Five children (seven limbs) had infantile Blount's disease with Langenskiold stage <= 2. Nine children (11 limbs) had late-onset Blount's disease. The mean age at operation was 7.2 years (SD, 3.1, range, 2.9-11.8). The tension-band plate effectively corrected the varus deformity in 78% (14/18) of limbs. Correction to normal mechanical alignment was achieved in 67% (n = 12) of limbs at a mean of 18 months (SD, 7, range, 9-31). Failure to achieve correction of the mechanical axis was due to delayed implant removal and overcorrection in 11% (2/18), mechanical failure due to screw fixation failure in 11% (2/18) and in 6% (1/18) due to a misplaced epiphyseal screw. There was a greater magnitude of correction in the Infantile Blount's disease group (mean, 26 degrees, SD, 9 degrees) when compared to the children with late-onset Blount's disease (13 degrees, SD, 4 degrees) (P = 0.021). The mean correction rate was 1.8 degrees/month in the Infantile Blount's disease group and 0.7 degrees/month in the late-onset Blount's disease group, respectively (P = 0.014). Our findings support the use of tension-band plating in Blount's disease. Further research is required to determine the ideal indications and to investigate the long-term outcome of guided growth in Blount's disease. Level of evidence: Level 4.

Automated summary

The objective of our observational study was to determine the effectiveness of guided growth with tension-band plates in correcting deformity in Blount's disease. Results showed that tension-band plates effectively corrected varus deformity in 78% of limbs, with 67% of limbs achieving normal mechanical alignment. The magnitude and rate of correction were higher in the Infantile Blount's disease group compared to the late-onset Blount's disease group.