Congenital Forearm Pseudarthrosis, a Systematic Review for a Treatment Algorithm on a Rare Condition

Free fibula flap to achieve bone union after congenital pseudoarthrosis of the forearm in neurofibromatosis: Technical report based on 3 cases, and literature review

Congenital pseudarthrosis of the forearm bones (CPFBs) is rare, with only 106 reported cases, and is frequently associated with neurofibromatosis (NF). Approximately 5% of patients with NF develop pseudarthrosis, and 50% of patients with pseudarthrosis have NF. Achieving bone union is difficult in congenital pseudarthrosis. Many methods have been attempted, including casting, internal fixation with or without grafting, and electrical stimulation, but failure is frequent. Free vascularized fibular flaps (FVFs) have been used to bridge long bone defects since 1975 and in tibial pseudarthrosis since 1979. In CPFB, FVF is more successful than other methods in achieving union and is the current treatment of choice. Here, we presented three cases of forearm pseudarthrosis treated with FVF, reviewed the literature on CPFB, and discussed some technical aspects of FVF treatment. Three cases of congenital pseudoarthrosis were treated with free fibula flaps, diagnosed at ages of 7 years (ulna), 15 months (radius), and 9 years (radius and ulna). Two flaps were stabilized with intramedullary wires and latterly, one with compression plates. One persistent nonunion received revision nonvascularized bone grafting and plating. All patients achieved union by 11 months after index surgery. Reconstruction with vascularized fibula is the treatment of choice because it offers the highest published union rates and good functional results. Complete resection of the affected bone and stable fixation, latterly with compression plates are critical to success. Surgery is technically demanding, and complications are common. Secondary surgery may be required, but outcomes are favorable. LEVEL OF EVIDENCE: IV.

The use of flexible nails in the treatment of paediatric long bone fractures: Experience at a level one paediatric trauma centre, a cohort study

Introduction

Fractures occur in children at an incidence only surpassed by women >85 years and account for 25 % of paediatric injuries. Over the last three decades, there has been a trend towards operative management of children's fractures including utilisation of flexible nails as popularised by the Nancy group in the 1980s. Between 5 and 11 % of paediatric forearm fractures are now fixed in this manner with complication rates of 12-42 %. This study shares the experience of a paediatric level one major trauma centre using this technique in managing long bone fractures in children.

Methods and materials

This retrospective cohort study comprises a sequential series of 109 cases (71 children) of upper and lower limb fractures in children (aged 16 years and below) who underwent fracture fixation using flexible intramedullary nails between 1st April 2015 and 31st March 2019. Radiological and clinical outcomes and complications were assessed.

Results

Ninety-three cases (10 in the lower limb, 83 in the upper limb) satisfied the inclusion criteria in 57 children with a mean age of 8.6 years. All cases were successfully reduced intra-operatively and 92 (98.9 %) achieved union. Taking into account all complications in the upper and lower limb, the overall complication rate is 30.1 % (28 cases) with the vast majority (13 cases, 46.4 %) occurring in the upper limb due to prominence of metalwork prompting early removal.

Conclusions

This study has shown flexible intramedullary nailing to perform well with good stabilisation of a wide variety of paediatric long bone fractures with restoration of bone alignment, satisfactory outcomes with good union rates and a return to normal function. The technique is also safe and in the upper limb can be performed as day-case surgery by a generalist orthopaedic surgeon. Although the overall complication rate is not insignificant, major complications are rare.

Vascularized Growth Plate Transfer in Paediatric Ulna Non-Union: Operative Technique and Review of the Literature

Congenital pseudarthrosis of forearm fractures is rare and is strongly associated with neurofibromatosis type 1 (NF1). Our case report illustrates the progression of a non-union of the ulna after minor trauma in a twelve-year-old boy, newly diagnosed with NF1, and presents the technique of microsurgical bone reconstruction, including the growth plate. More than seven years after the first operation, follow-up presents a favorable outcome with a pain-free patient and unrestricted function of the forearm after a secondary correction of the remaining radial bowing. This treatment is discussed with a comprehensive review of the current literature on ulnar congenital pseudarthrosis in PubMed and Google Scholar and free fibular growth plate transfer in PubMed and Google Scholar. Nine publications reporting on 20 cases of congenital ulnar non-unions were identified. With this reconstructive option, favorable outcomes were achieved in all cases with the union after primary surgery and complications requiring further surgeries in nine cases. The benefit of vascularized growth plate bone transfer in congenital ulna non-union seems to be significant compared to other therapies such as open reduction internal fixation (ORIF), non-vascularized bone grafts, or one-bone-forearms and beneficial when growth reconstruction is needed. Other techniques might be necessary to improve insufficient long-term results.

Traumatic Radius Pseudoarthrosis in Neurofibromatosis Type 1: All Treatment Options in One Patient

Although congenital pseudoarthrosis of the radius is a rare case, it has been reported many times in the literature in the past and it has been shown that it can be associated with neurofibromatosis type 1. However, traumatic radius pseudoarthrosis has never been reported before. In this case report, all treatment options were applied to the same patient over a four-year period and the results were reported. A two-year-old boy had a left radius diaphysis fracture after a simple fall, and bone union could not be achieved despite the application of cast immobilization, internal fixation grafting, and electrical stimulation in an external center. He was admitted to our hospital when he was six years old. A plain X-ray image and computed tomography scan showed that he had radius pseudoarthrosis and also he was diagnosed with neurofibromatosis type 1 on genetic analysis. The patient underwent wide resection of the segment with pseudoarthrosis and free vascularized fibula grafting. Bone union was achieved in the third postoperative month.

Microsurgery in pediatric upper limb reconstructions: An overview

The use of microsurgery has spread during the last decades, making resolvable many complex defects considered hitherto inapproachable. Although the small vessel diameter in children was initially considered a technical limitation, the increase in microsurgical expertise over the past three decades allowed us to manage many pediatric conditions by means of free tissue transfers. Pediatric microsurgery has been shown to be feasible, gaining a prominent place in the treatment of children affected by limb malformations, tumors, nerve injuries, and post-traumatic defects. The aim of this current concepts review is to describe the more frequent pediatric upper limb conditions in which the use of microsurgical reconstructions should be considered in the range of treatment options.

Treatment of Recalcitrant Nonunion of the Radius With Posterior Interosseous Bone Flap in Children

BACKGROUND

Forearm nonunion is a rare condition in children, and its treatment is usually successful. However, nontraumatic nonunion can be resistant to treatment. Although the vascularized fibular bone graft has been frequently used for complex forearm nonunion, there is no consensus on the best treatment method. In this study, we aimed to investigate the outcome of the antegrade posterior interosseous bone flap (PIBF) in treating children with complex radius nonunion.

METHODS

The participants consisted of 3 girls and 1 boy ranging from 31 months to 9 years of age. They were treated with PIBF surgery, and the nonunion of the radius was fixed with a plate or an external fixator. The nonunion was due to congenital pseudoarthrosis, osteogenesis imperfecta, or infantile osteomyelitis. All patients were evaluated for a clinical and radiologic union.

RESULTS

The radiologic union was achieved 2 to 3 months after the surgery in all cases. The functional recovery of the elbow, forearm, and wrist was satisfactory except for 1 patient who experienced donor site fracture, and finally radioulnar synostosis accompanied by radial head dislocation.

CONCLUSION

Because of the simplicity of its technique and short duration of surgery, PIBF can be a reliable and less-demanding alternative to vascularized fibular bone graft in the treatment of complex forearm nonunion in children.

LEVEL OF EVIDENCE

Level IV.

Congenital pseudarthrosis of the forearm as a single manifestation of neurofibromatosis type 1 at birth: A case report

Congenital pseudoarthrosis of the forearm is an extremely rare condition. It is most commonly associated with neurofibromatosis type I (NF1). Patients with NF1-associated pseudoarthrosis have complex medical management and often require surgical intervention due to higher failure rates of union. In this case report, we present a unique case of a newborn baby with congenital pseudoarthrosis of both the radius and ulna that was manifested at birth and shortly thereafter, was diagnosed with NF type 1.

Subcutaneous Calcification and Fixed Flexion Deformity of the Right Elbow Joint in a Child with a GNAS Mutation: A Case Report

INTRODUCTION

The art of medicine glorifies when a clinician listens carefully to the patient's story, gives a thorough examination, performs appropriate investigations, and finally links findings together to reach a definite diagnosis. An interesting case was reported here, highlighting the integration of different symptoms and manifestations with some relevant biochemical investigations to reach a final diagnosis. To the best of our knowledge, fixed flexion deformity, as a complication of subcutaneous calcification, has not been previously reported in a child with Albright hereditary osteodystrophy (AHO).

CASE PRESENTATION

A 2.5-year-old boy was born at term with a birth weight of 3.5 kg (-0.49 SDS). The child was referred to a general pediatrician with a history of right elbow joint swelling noticed initially at six months of age. He then developed the limitation of right upper arm movement, which slowly progressed afterward. The patient had no history of trauma. At nine months of age, he was diagnosed with hypothyroidism, preceded by cold skin, dry hair, and constipation. At nine years of age, he presented with a fixed flexion deformity of the right elbow associated with markedly limited joint movement and symmetrical hands with hyperpigmented knuckles of right metacarpal bones. Subcutaneous masses were felt along the right forearm, showing tenderness on palpation. Investigations revealed elevated serum parathyroid hormone and normal calcium indicating parathyroid hormone resistance. Further genetic testing revealed GNAS mutation. The child was obese throughout his childhood.

CONCLUSIONS

This case report describes an obese child with subcutaneous calcification that led to fixed flexion deformity of the elbow, starting at an incredibly early age. Hypothyroidism and pseudohypoparathyroidism raised the suspicion of AHO, which was later confirmed by genetic testing. This is the first case report on fixed flexion deformity in a patient with GNAS mutation (c.719-1G > A Chr20: 57484737) in West Asia.

Congenital pseudoarthrosis of the radius in Neurofibromatosis Type 1: An entity not to be missed!

Congenital pseudoarthrosis of the radius is exceedingly rare. We report an isolated pseudoarthrosis of the radius in a five-year-old girl child with Neurofibromatosis type-I (NF-I). She underwent excision of the pseudoarthrosis tissue, ulna osteotomy, iliac crest cortico-cancellous bone grafting, and K wire fixation of both bones. A sound union of the radius and the ulna was achieved after 4 months. At two-year follow-up, mild shortening of the forearm persisted with maintenance of sound union of both bones. Accurate diagnosis of the condition is central in avoiding complications and the need for complex surgical procedures.