What is congenital pseudarthrosis of the tibia?
Congenital tibial pseudarthrosis is a rare condition and one of the most difficult to treat in pediatric orthopedics.
It can be associated with other conditions (neurofibromatosis in over 50% of cases, fibrous dysplasia and Campanacci osteofibrous dysplasia in 10%) or stand alone.
Congenital pseudarthrosis of the tibia: presentation
The initial presentation can be with:
- a characteristic anterolateral curvature of the leg (Antero-Lateral Bowing) with a tendency to progressively deform and fracture
- already with a tibial fracture at presentation
A fracture of the tibia (usually associated with that of the fibula) usually occurs in the lower part of the leg and has two specific characteristics:
- It does not cause an acute and painful condition like normal leg fractures: parents often notice an abnormal movement in the middle of the leg without it causing pain.
- it does not undergo consolidation (unlike common leg fractures), therefore it is defined as a pseudoarthrosis.
This progressively causes numerous problems: loss of stability of the leg, progressive deformity of the ankle and foot, muscle atrophy, shortening of the limb.
Congenital pseudarthrosis of the tibia: natural history
The natural history of congenital pseudoarthrosis of the tibia is therefore that of a leg that is mostly normal at birth, but which progressively deforms and shortens, leading to severe functional disability for the patient.
Treatment of congenital tibial pseudarthrosis: which is the most effective?
Over the years, various types of treatment have been proposed, but each traditional treatment has shown limitations and complications. Above all, no treatment has been proven to be reproducibly and absolutely effective in all cases.
Traditional treatments
Among the most frequently performed traditional treatments:
- Resection of congenital nonunion with intramedullary nailing . This is the most commonly used treatment. The pathological area is removed and the bone is fixed with internal systems (K-wires, Rush, telescopic nails). Bone grafts taken from the patient’s own pelvis or stem cells are also inserted into the pathological area.
The success rates reported in the literature are around 40%, thus very limited.
The most frequent complications include breakage or dislodgement of the inserted fixation devices, the need to repeatedly replace them, and complications affecting the ankle and foot in cases where the fixation devices were inserted from the foot itself (stiffness, deformity, damage to the growth plate, etc.).
- Resection of congenital nonunion and external fixation (Ilizarov). External fixation can be used in specific cases or at the end of growth, when resection of the nonunion is combined with restoration of limb length.
Success rates reported in the literature are around 57%. - Vascularized fibula . This is a complex surgical technique that involves intrinsic problems (the fibula is harvested from the healthy contralateral leg).
The success rates described in the literature are around 58%.
Modern treatments for congenital pseudarthrosis of the tibia
Paley’s combined treatment of congenital tibial pseudarthrosis
This is the treatment that, in our experience and in the literature (success rates reported up to 100%, but further studies from more centers will need to be evaluated over time), is showing the best results.
The method combines different procedures together to treat all aspects (biomechanical, anatomopathological and biological) of the pathology:
- Resection of the congenital pseudarthrosis area and of the pathological periosteum
- Intramedullary nailing of the tibia and fibula
- Massive bone graft from the pelvis
- Periosteum graft from the pelvis
- Further synthesis with plate or external fixator
- Infusion (before and after surgery) of zoledronic acid to limit bone resorption in the operated area
This is a complex procedure that requires experience in the individual parts of the procedure, but it can yield excellent results.
Treatment of deformity in the pre-pseudarthrosis stage
In the initial phase, when the bone appears curved, it is essential to try to limit the progression of the deformity to reduce the risk of fracture.
To this end, it is useful to perform temporary hemiepiphysiodesis (see fact sheet), which guides the growth of the growth plates, thus making the affected bone less deformed.
Recent studies have demonstrated the effectiveness of this procedure in preventing fractures.
Essential bibliography
- Paley D. Congenital pseudarthrosis of the tibia: biological and biomechanical considerations to achieve union and prevent refracture, J Child Orthop. 2019 Apr 1;13(2):120-133.
- Wu C, Zheng G, Wang D, Paley D, Ning B. Combination Treatment by Cross-Union of the Tibia and Fibula, Autogenic Iliac Bone Grafting, Reliable Fixation and Bone Morphogenetic Proteins for the Treatment of Refractory Congenital Pseudarthrosis of the Tibia. J Pediatr Orthop. 2022 Jul 1;42(6):e623-e629.
- Laine JC, Novotny SA, Weber EW, Georgiadis AG, Dahl MT. Distal Tibial Guided Growth for Anterolateral Bowing of the Tibia: Fracture May Be Prevented. J Bone Joint Surg Am. 2020 Dec 2;102(23):2077-2086.
- Lampasi M , Antonioli D, Di Gennaro GL, Magnani M, Donzelli O. Congenital pseudarthrosis of the fibula and valgus deformity of the ankle in young children. J Pediatr Orthop B. 2008 Nov;17(6):315-21.