The 30.4% rate of physeal bars reported in a recent series from Seattle Children's is high: 17 of 56 children with Salter–Harris III or IV medial malleolus fractures developed a bar, and almost half of those children subsequently needed further surgery. [1]
This finding deserves attention, but concerns a very specific subgroup. It cannot be applied to all fractures involving the distal tibial growth plate.
Where the 30% figure comes from
The study included skeletally immature children with Salter–Harris (SH) III or IV medial malleolus fractures: intra-articular injuries that cross the growth plate. Of the 161 cases initially identified, 56 had an open growth plate and at least six months of radiographic follow-up. A physeal bar developed in 17 cases and was diagnosed, on average, 8.4 months after injury. [1]
Series including all types of distal tibial physeal fractures report a lower risk of premature closure. A 2021 meta-analysis involving almost 2,000 patients reported approximately 13%; a Finnish population-based cohort reported approximately 11%. [3][4]
These percentages are not contradictory. They describe different populations.
This is not an isolated finding
In 2003, Barmada and colleagues had already reported premature physeal closure in up to 38% of the subgroup with SH III–IV medial malleolus fractures. [2]
Other studies have reported lower figures. A 2026 series of 60 children with surgically treated medial SH III–IV fractures documented premature closure in eight patients, or approximately 13%. [5]
Variation between studies reflects patient selection, outcome definitions, follow-up duration and the initial characteristics of the fracture. The 30% figure is therefore a useful reminder that these injuries may carry substantial risk, but is much less useful as a percentage to give to every family without distinction.
Initial displacement appears to matter
In the Seattle Children's study, children who developed a bar had greater mean initial displacement: 5.4 mm compared with 3.3 mm. A larger proportion of the growth plate was also involved in the coronal plane. [1]
Across the broader literature on distal tibial fractures, greater initial damage to the growth plate and repeated reduction attempts have been associated with a higher risk of growth arrest. [3][4]
A displaced intra-articular fracture therefore requires a precise reduction strategy. Repeated manipulation in pursuit of a marginal improvement can add further trauma to an already injured growth plate.
What surgery can and cannot do
Fixation does not eliminate the risk of a physeal bar. The growth plate is damaged at the time of injury, and that damage may be sufficient to cause growth arrest even after anatomical reduction.
Surgery has a different objective: restoring joint congruity and reducing residual displacement when the fracture requires it.
In SH III–IV medial malleolus fractures, we cannot rely on remodelling of an articular step as we might at other sites. A series examining poor outcomes had already reported that even 2 mm of malreduction could be poorly tolerated. [6]
A bar developing after technically sound fixation does not therefore necessarily mean that surgery has failed. Equally, the risk of a bar is not a reason to accept an inadequate articular reduction.
Follow-up continues after fracture union
In the 2026 study, a bar was recognised after an average of 8.4 months, and the authors recommend radiographic follow-up for at least 12 months. [1]
Children with considerable remaining growth may need longer follow-up if growth plate symmetry is not clearly established. A child may be pain-free and back to all activities while still showing the first signs of partial closure.
Growth plate asymmetry, progressive changes in alignment or asymmetric Harris growth lines may warrant further investigation. Depending on the case, comparative radiographs and more detailed imaging help define the position and extent of a bar and estimate remaining growth.
The consequences also depend on these factors: a small bar in a child with years of growth ahead is not equivalent to almost complete closure near skeletal maturity.
What to explain to the family
Salter–Harris III and IV medial malleolus fractures need closer follow-up than many other childhood ankle fractures. The risk of a growth disturbance depends on the severity of the original injury, the proportion of the growth plate involved and the amount of growth remaining.
After fracture union, follow-up is no longer about checking whether the bone has “joined together”. It is about checking that the distal tibia continues to grow normally.
The 30.4% figure from the recent study should be remembered for what it represents: a strong signal in a high-risk subgroup, not the average probability of growth arrest after any distal tibial physeal fracture.
References
[1] Roth OS, Gupta A, Adebayo T, Tretiakov M. Risk Factors and Surgical Sequelae of Physeal Arrest in Pediatric Salter-Harris III and IV Medial Malleolus Fractures. J Pediatr Orthop. 2026;46(7):e618-e625. doi:10.1097/BPO.0000000000003160.
[2] Barmada A, Gaynor T, Mubarak SJ. Premature physeal closure following distal tibia physeal fractures: a new radiographic predictor. J Pediatr Orthop. 2003;23(6):733-739. doi:10.1097/00004694-200311000-00010.
[3] Jalkanen J, Sinikumpu JJ, Puhakka J, et al. Physeal Fractures of Distal Tibia: A Systematic Review and Meta-analysis. J Pediatr Orthop. 2021;41(7):e506-e511. doi:10.1097/BPO.0000000000001833.
[4] Stenroos A, Puhakka J, Jalkanen J, et al. Risk of premature physeal closure in fractures of distal tibia. J Pediatr Orthop B. 2021;30(1):25-31. doi:10.1097/BPB.0000000000000744.
[5] Pehlivanoglu G, Albayrak K, Aykut US, et al. Comparative outcomes of Kirschner wire and lag screw fixation in pediatric medial malleolar fractures. J Orthop Surg Res. 2026;21:213. doi:10.1186/s13018-026-06726-2.
[6] Luhmann SJ, Oda JE, O’Donnell J, et al. An analysis of suboptimal outcomes of medial malleolus fractures in skeletally immature children. Am J Orthop. 2012;41(3):113-116. PMID:22530207.
Disclaimer: This article provides general information and does not replace an individual medical assessment.
