Comparative Trial of Operative Treatment of Distal Pediatric Forearm Fractures With Biodegradable Nails and K-wires

Over the last decade, there has been an increasing demand to overcome the disadvantages associated with conventional implant materials, by developing new, alternative materials and material production approaches for use in trauma care.

In recent years there has been a growing interest in the orthopaedic application of resorbable implants. Their use in children may be particularly beneficial. Poly(L-lactide)-co-glycolide acid (PLGA) is a well-known, reliable biodegradable material that has been used in bone surgery for more than 20 years. Several publications have already reported the successful use of intra-medullar PLGA implants in the treatment of paediatric diaphyseal forearm fractures.

To gather further evidence about the clinical value of the new method with PLGA - based bioresorbable implant in regard to patients benefit, a multicenter prospective trial is needed. This trial will be conducted on the distal forearm, which is one of the most common fracture locations that requires surgical intervention in children. Severely displaced distal paediatric forearm fractures will be addressed.

Distal paediatric forearm injuries

Distal radius fractures are among the most common injuries of childhood. Optimal treatment for distal radius fractures is still controversial. Treatment of severely displaced and shortened fractures usually require general narcosis and closed reduction. Most authors recommend osteosynthesis if the fracture remains unstable after reduction. The gold standard operative method for these fractures is closed reduction, percutaneous pinning with Kirschner-wires.

Kirschner-wire related minor complications are relatively frequent. Migration of the pins, superficial infections, skin irritation are well manageable but significantly impair the child's sense of comfort. Deep infections, tendon or nerve injuries may occur less often. There is a controversy as to whether it is preferable to leave the wires outside the skin. While wires left out of the skin increase the risk of infection, wires buried under the skin can be removed with a second intervention. Removing the implants can also cause complications.

K-wires are not capable of providing sufficient stabilization in this indication, so additional casting treatment is also required. The duration and the type of postoperative immobilization varies greatly according to the practice of the surgeons. There is no evidence about the most optimal immobilization procedure. 4-6 weeks of cast wearing is recommended by most authors. This causes stiffness in the affected joints and delays the recovery of full function. Fractures with intramedullary elastic nails require a reduced time of immobilization because they provide a more stable synthesis, but nails can be removed only under general anaesthesia. The use of bioabsorbable intramedullary nails in distal paediatric forearm fractures may eliminate all of the above-mentioned disadvantages.

The study is designed as a multicenter trial for the treatment of distal pediatric forearm fractures (=severely displaced distal metaphyseal forearm fractures) with a PLGA-based biodegradable intramedullary implant in children. The primary objective of the trial is to evaluate clinical outcome between Activa IM-Nail™ and K-wire in this indication. The secondary objective is to evaluate potential differences of potential complications in the operative method with either a biodegradable intramedullary PLGA-implant or with conventional K-wires. K-wire osteosynthesis will be made according to the conventional surgical technique by two paediatric trauma centers. Intramedullary PLGA implantation will be made by the Péterfy Hospital. The surgical indication will be the same in all groups, and follow-up will follow standard protocols. In the further clinical course, the patients in the study group treated with PLGA implants spare a subsequent operation for implant removal after 4-8 weeks. The results of different surgeries will be compared based on several criteria.