Congenital pseudarthrosis of the ulna: a report of two cases and a review of the literature

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.

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

BACKGROUND

A congenital forearm pseudarthrosis is a rare condition and is strongly associated with neurofibromatosis type 1. Several surgical techniques are described in the literature, but the most optimal treatment strategy remains unclear. This systematic review aims to develop a treatment algorithm that may aid in clinical decision making.

METHODS

The PROSPERO registration number for this study was CRD42018099602 and adheres to the PRISMA guidelines for systematic reviews. Embase, MEDLINE, Cochrane Central, Web of Science, and Google Scholar databases were searched for published studies reporting on congenital forearm pseudarthrosis not related to other underlying pathologies like bacterial infection or fibrous dysplasia. Results were not restricted by date or study type, only English literature was allowed. Studies were assessed for quality using the critical appraisal checklist for case reports from the Joanna Briggs Institute. Patient characteristics, underlying disease, type of surgery, union rate, and functional outcome were extracted from included studies.

RESULTS

Of 829 studies identified, 47 were included in this review (17 case series and 30 case reports, a total of 84 cases). A one-bone forearm procedure showed highest union rates (92%), however, it results in loss of forearm rotation. Free vascularized fibula grafting showed high union rates (87%) and was related to good functional outcome of elbow flexion and forearm rotations. Other procedures showed disappointing outcomes.

CONCLUSIONS

Congenital forearm pseudarthrosis is best treated with a free vascularized fibula grafting, a one-bone forearm procedure should be used as a salvage procedure. Evidence extracted from the case reports was sufficient to generate a treatment algorithm to be used in clinical pediatric practice.

LEVEL OF EVIDENCE

Level IV-therapeutic.

Pseudoartrosis congénita de antebrazo asociada a luxación de radio proximal: Tratamiento quirúrgico mediante antebrazo de un solo hueso. [Congenital forearm pseudoarthrosis associated with proximal radius dislocation: Surgical treatment using a single bone forearm.]

<p><strong>Introducción</strong></p><p><strong></strong>La pseudoartrosis congénita de antebrazo es una entidad clínica rara que se asocia a habitualmente Neurofibromatosis tipo 1. La lesión de ambos huesos del antebrazo asociada con luxación de cabeza de radio es extremadamente inusual.</p><p><strong><em> </em>Material y métodos</strong></p><p><strong></strong>Se presenta el caso de una niña de 13 años de edad con Neurofibromatosis tipo 1 y pseudoartrosis de ambos huesos del antebrazo asociada a luxación de la cabeza de radio. Se le realizó escisión amplia de la pseudoartrosis y reconstrucción mediante antebrazo de un hueso con placa. La primer cirugía fracasó y requirió una revisión con retiro del implante, injerto óseo autólogo y fijación con enclavado endomedular. Luego de la segunda cirugía, la niña presenta un antebrazo de un hueso estable, con un acortamiento de 7cms. En el último control, 4 años después, la paciente se encuentra asintomática y utiliza el miembro superior con una mínima limitación de la flexo-extensión de muñeca.</p><p><em> </em><strong>Conclusión</strong></p><p><strong></strong>La reconstrucción mediante antebrazo de un hueso es una opción razonable para la pseudoartrosis de ambos huesos del antebrazo con luxación de cabeza radial en niños. El procedimiento de salvataje, produce un miembro superior estable, con una función satisfactoria de muñeca y codo.</p>

Complications and Outcomes of One-Bone Forearm Reconstruction

Background: The objective of this study was to review the outcomes of patients who underwent one-bone forearm (OBF) reconstruction. Methods: A retrospective review of patients who underwent OBF surgery between 1994 and 2014 was undertaken. Patient demographics, etiology, associated injuries, number of surgeries prior to OBF surgery, surgical details, and postoperative information were collected. A telephone interview was conducted at final follow-up, including a Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) questionnaire, a 10-point scoring system used by Peterson et al, and a series of questions concerning pain and patient satisfaction. Results: There were 6 males and 2 females with a mean age of 44 years (range, 20-66 years). All patients had traumatic etiology, with 6 having open wounds and 2 having closed wounds. All patients had union with a mean follow-up of 83.6 months (range, 16-218 months). The mean pain score was 3 (range, 0-8), of which 3 were painless (score 0). The mean QuickDASH score was 39 (range, 7-75), and 4 patients had good or excellent results according to the 10-point score system used by Peterson et al. All patients were satisfied with the result. Five of 8 had complications related to soft tissues that were residual from their prior injuries and surgeries. One patient had post healing fracture requiring revision fixation and 1 had a postoperative infection requiring parenteral antibiotics. Conclusions: OBF surgery is an effective salvage procedure for complicated forearm instability, particularly after trauma. While union rates are high, complications are typically related to pain and soft tissue secondary to the previous injury and reconstructive procedures.

Congenital pseudarthrosis of the radius treated with gradual distraction and free vascularized fibular graft: case report

Only 18 cases of congenital radial pseudarthrosis have been reported in the English literature; of these, 4 have been treated with free vascularized fibular graft. We present a case of a 9-year-old female patient with neurofibromatosis type 1 who underwent gradual distraction through the pseudarthrosis site and subsequent vascularized fibular grafting for isolated congenital pseudarthrosis of her left radius and concomitant longitudinal and angular deformity of the wrist joint. At the last follow-up, 10 years postoperatively, the patient has maintained bony union, with full wrist flexion-extension and forearm pronation-supination.

Free vascularized fibular flap for congenital ulnar pseudarthrosis: a report of two cases and review of the literature

Congenital pseudarthrosis of the ulna (CPU) is an extremely rare disorder that has been treated with various traditional methods with poor results on long-term deformity correction and bony union. Free vascularized fibular grafting (FVFG) has been used to treat congenital pseudarthroses with improved success rates. We report herein 2 cases of CPU treated with FVFG in which bone union was obtained without major difficulty. The distal ulnar hypoplastic physis and epiphysis were spared during excision of the pseudarthrosis in both cases leading to continuous ulnar growth following bone healing. The main challenge concerned the stability of the radiocapitellar joint. There was no complication at the donor site. Free vascularized fibula is a safe and effective method for the treatment of congenital pseudarthrosis of the ulna.

Congenital pseudoarthrosis associated with venous malformation

Congenital pseudoarthrosis is a pathologic entity that may be isolated, or may be associated with neurofibromatosis. We report the case of a 3-year-old female with congenital pseudoarthrosis involving the right tibia and fibula. Magnetic resonance imaging (MRI) and complementary magnetic resonance angiogram (MRA) revealed a lobulated mass with vivid enhancement, which led to the diagnosis of venous malformation. This is the first report of congenital pseudoarthrosis caused by the presence of a vascular malformation.

Use of free vascularized fibular graft for congenital ulnar pseudarthrosis: surgical decision making in the growing child

Congenital pseudarthrosis of the ulna may cause growth disturbance and progressive forearm deformity, leading to functional compromise of the upper extremity. Treatment is challenging, and surgical decision making must take into account three goals of treatment: bony healing, distal radioulnar joint (DRUJ) stability, and continued skeletal growth. Four cases of congenital ulnar pseudarthrosis treated with free vascularized fibular graft are presented here. In two cases, the vascularized fibular graft included the proximal fibular epiphysis to reconstruct the DRUJ and ulnocarpal joints. Average age of the four patients at time of vascularized fibular grafting was 10 years (range 3-16 years). Patients had undergone up to three previous failed operations. A step-cut osteotomy technique with rigid internal fixation was used in all patients. Donor-site distal tibiofibular arthrodesis was performed in skeletally immature patients when appropriate. At average follow-up of 60 months (range 33-83 months), all patients achieved bony union with full wrist range of motion compared with the contralateral extremity. The DRUJ was stable in all patients. Two skeletally immature patients with concomitant epiphyseal transfer showed continued skeletal growth. Two patients nearing skeletal maturity achieved revascularization of the distal ulna. Free vascularized fibular grafting is a successful option in the treatment of congenital ulnar pseudarthrosis. Reconstruction of the distal radioulnar and ulnocarpal joints using concomitant proximal fibular epiphyseal transfer should be considered in the skeletally immature patient with distal ulnar involvement.

Pseudarthrose congénitale de l’avant-bras associée à la neurofibromatose

We report a case of congenital pseudarthrosis of the forearm associated with neurofibromatosis type 1 which was treated by free vascularized periosteal flap transplant and repeated bone grafting. The young female patient recovered good hand and forearm function. A review of the literature revealed the rare occurrence of this disease (approximately 100 cases reported to date), which probably explains the wide variety of surgical proposals.

Congenital pseudarthrosis of the ulna treated by free vascularized fibular graft--a case report

Congenital pseudarthrosis of the ulna is very rare. We have experienced a case of pseudarthrosis of ulna to be treated with the vascularized fibular graft in a seven-years-and-three-month-old boy.

Congenital pseudarthrosis of the forearm treated by free vascularized fibular graft: a report of three cases and a review of the literature

Congenital pseudarthrosis of the forearm is a rare condition; approximately 60 cases have been reported in the English literature. We report 3 patients treated by wide excision of the pseudarthrosis and free vascularized fibular grafting. The pseudarthrosis involved the radius in 1 patient and the ulna in 2. Neurofibromatosis was present in 2 patients. The technical problems encountered during the procedures included preservation of the distal epiphysis and attaining stable fixation of the fibular graft without damaging its vascular supply. A review of 15 previously reported patients treated by free vascularized fibular grafting showed that this procedure is excellent in the treatment of congenital pseudarthrosis of the forearm and that the result is consistently reproducible.

Clinical results of the one-bone forearm

Between 1973 and 1991, 19 patients underwent creation of a one-bone forearm at our institution as treatment for radioulnar instability secondary to trauma ("type 1" patients) or tumor resection or congenital deformity ("type 2" patients). Seventeen had failed previous reconstruction attempts. Ten one-bone forearms were constructed in neutral rotation, and nine in varying pronation (mean, 24 degrees). The distal ulna was absent or excised at the time of surgery in nine patients, partially excised in two, and shortened in one. At a mean follow-up interval of 42 months, the primary union rate was 68%, and the secondary rate was 74%. Using a rating scale devised for this study, 37% excellent, 32% good, 26% fair, and 5% poor results were noted. Poor results were statistically associated with previous trauma (type 1 patients), infection, severe nerve injury, and multiple previous surgical procedures. This is a retrospective study, and because of the limitations of such studies, no correlation of results with forearm rotational position, preoperative wrist or elbow dysfunction, fusion location, distal ulna excision or synostosis union was noted. Significant complications were noted in 10 patients, with a higher rate in type 1 patients. Although one-bone forearm construction remains a viable salvage option for forearm instability in selected patients, results may be less predictable than previously reported.

Congenital pseudarthrosis of the ulna

Congenital ulnar pseudarthrosis is a very rare condition. Two cases are reported in addition to 36 already reported in the English literature. One of the cases reported had a "one-bone forearm" procedure done, with a satisfactory result after 6 years. The second case had a free vascularized fibula graft procedure with restoration of the bony alignment and union after 8 months of follow-up.

Congenital pseudarthrosis of the ulna treated by free vascularized fibular graft: a case report and review of methods of treatment

Congenital pseudarthrosis of the ulna is an extremely rare condition for which current surgical techniques have been unsatisfactory in restoring a normal two-bone forearm. We report a case which was treated by excision of the ulnar pseudarthrosis and interposition of a free vascularized fibular graft with a skin island to monitor anastomotic patency. Forearm rotation has been restored and the potential for normal forearm growth has been preserved.

Congenital pseudarthrosis of the forearm: treatment of six cases with vascularized fibular graft and a review of the literature

Six cases of pseudarthrosis of the forearm are reported. One involved only the radius, one the ulna alone, and four both forearm bones. There was associated neurofibromatosis in five cases. All the cases were treated by wide resection and free vascularized fibular graft. In two cases, a single-bone forearm was created. In all cases, good results were achieved, with moderate forearm shortening. The literature suggests electrical stimulation, corticoperiosteal graft, osteotomy of the involved bone, and free vascularized bone grafting as treatment alternatives. Vascularized free bone grafting appears to be more successful than other treatments. The use of microsurgical sutures permits this treatment in young patients.

Pseudoarthrosis of the ulna in neurofibromatosis. A report of four cases

Four children suffering from neurofibromatosis with ulnar pseudarthrosis and progressive reabsorption of the middle and distal thirds of the ulna are reported. None had any pain or sensory loss, but all had progressive deformity of the forearm. Instability of the elbow and wrist were present in three cases, while one case showed good stability and function. A cross-union of the ulna with the radius to produce a one-bone forearm was accomplished using screw fixation and iliac bone grafting, and a one-bone forearm was achieved in three cases. Non-operative management was decided on in the patient with slow ulna reabsorption. The creation of a one-bone forearm is more likely to produce sound union, thus avoiding the need for further operations, while conservative management should be reserved for patients with a slowly progressive condition.