Pedicled Sensate Composite Calcaneal Flap in Children With Congenital Tibial Pseudoarthrosis.

BACKGROUND: The preservation and functionality of a limb affected by a malformation (such as congenital pseudoarthrosis of the tibia) or a severely mangled lower limb in children, despite modern reconstructive techniques, remains challenging, often eventually requiring amputation to achieve a better outcome. The classical Syme and Boyd procedures are functionally better than transtibial (TT) amputation, but are not feasible for congenital tibial pseudoarthrosis. TT amputation delivers an excellent, effective, and functional stump that usually leads, after prosthetization, to a functional gait. Unfortunately, in some situations, particularly when amputation is performed conventionally, the stump is also associated with complications. Future surgical revisions are often needed, particularly in children, because of stump overgrowth. METHODS: Between 2008 and 2010, three patients diagnosed with congenital pseudoarthrosis of the tibia associated with neurofibromatosis who were indicated for TT amputation with calcaneal flap after failure of all previous surgical reconstructive procedures were selected. The chosen method for osteosynthesis was an external fixator of Ilizarov. RESULTS: At 12 weeks of follow-up, the stump had healed in all three patients, and tibiocalcaneal fusion was achieved without complications. All patients were prosthetized and had an asymptomatic gait. After a minimum follow-up of 6 years, all three cases with the pedicled sensate composite calcaneal flap still had a strong, full weight-bearing surface and have adapted easily to the conventional prosthesis, providing a painless stump with excellent functionality. CONCLUSION: With a 0 rate of needed revisions, all 3 cases with the pedicled sensate composite calcaneal flap preserving the hind foot still have a strong, full weight-bearing surface and have easily adapted to the conventional prosthesis, providing a painless and excellent functional stump that could last a lifetime. LEVEL OF EVIDENCE: Level IV.

Prevalence of neurofibromatosis type 1 in congenital pseudarthrosis of the tibia.

UNLABELLED: A strong relationship between congenital pseudarthrosis of the tibia (CPT) and neurofibromatosis type 1 (NF1) has been suggested, but prevalence varies widely throughout the literature and the criteria used for diagnosis are very heterogeneous. Literature focus is mainly on treatment and no specific review on the prevalence of NF1 has been published. Based on our own observations, we hypothesized the prevalence of NF1 in patients with CPT to be higher than what is previously accepted. We conducted a comprehensive literature review on this topic and compared results with our study population. Twenty-one out of twenty-five patients in the study population matched the NIH diagnostic criteria for NF1 (84.0 %, CI95 = 69.6-98.4 %). These results are higher than the prevalence reported in the literature (55.4 %, CI95 = 50.4-60.4 %). CONCLUSIONS: The prevalence of NF1 in patients with CPT might be higher than what is reported until now because the criteria of NF1 generally appear only after the diagnosis of CPT. We propose a repeat meticulous examination and a multidisciplinary approach with a clinical genetic counseling in all CPT patients. WHAT IS KNOWN: • Congenital pseudarthrosis of the tibia and neurofibromatosis type 1 are closely related. • Literature focus is mainly on treatment and little epidemiologic research is available. What is New: • Prevalence of neurofibromatosis type 1 in patient with congenital pseudarthrosis of the tibia might be higher than what is reported until now. • A multidisciplinary approach with meticulous clinical examination and genetic counseling might lead to an earlier diagnosis of neurofibromatosis type 1 in patients with congenital pseudarthrosis of the tibia.

Effectiveness of recombinant human bone morphogenetic protein-7 in the management of congenital pseudoarthrosis of the tibia: a randomised controlled trial.

PURPOSE: Despite the popularity and an increased use of bone morphogenetic protein to improve bone healing in patients with congenital pseudoarthrosis of the tibia (CPT), no previous study has compared its efficacy against any other procedure. METHODS: We randomised 20 consecutive patients (mean age 4.1 years) with CPT (Crawford type IV) associated with neurofibromatosis type 1(NF1) and no previous history of surgery into two groups. Group 1 received recombinant human bone morphogenetic protein-7 (rhBMP-7) along with intramedullary Kirschner (K)-wire fixation and autologous bone grafting; group 2 received only K wire and grafting. Outcome measures were time to achieve union, Johnston grade, tibial length and the American Orthopaedic Foot and Ankle Society (AOFAS) score, which were evaluated preoperatively and at five year follow-up. RESULTS: Study results showed that patients in group 1 achieved primary bone union at a mean of 14.5 months [standard error (SE) 5.2], whereas group 2 took a mean of 17.11 months (SE 5.0). However, the log-rank test showed no difference in healing times between groups at all time points (P = 0.636). There was a statistically significant pre- to post operative improvement (P < 0.05) within groups for the other outcome measures. CONCLUSION: In a five year follow-up, these results suggest that rh-BMP-7 and autologous bone grafting is no better than autologous grafting alone.

Successful treatment of congenital pseudarthrosis of the tibia: still a challenge.

The congenital pseudarthrosis of the tibia (CPT) is one of the most challenging problems in pediatric orthopedics. The primary treatment goals are outlined as osteosynthesis, stabilization of the ankle mortise by fibular stabilization and lower-limb-length equalization. Despite the fact that each of the aforementioned goals is difficult to be achieved regardless the surgical option, the main biological consideration is the same: pseudarthrosis resection, biological bone bridging of the defect by stable fixation and the correction of any angular deformity. The external fixation method is suggested as valuable treatment of CPT because it can address not only pseudarthrosis but also all complex deformities associated with this condition. However, treatment of CPT is impaired with complications due to the complex nature of the disease thus failure is common. The most common of these are refracture, growth disturbance, poor foot and ankle function with stiffness. Of these, refracture is the most common and serious complication after primary healing and might result in the reestablishment of pseudarthrosis. Therefore, an effective, safe and practical treatment method that minimizes the residual challenges after healing and accomplishes the multiple goals of treatment is needed. In this article, we report a patient with CPT treated successfully with external fixation. Level of evidence IV retrospective.

Breakage of an intramedullary rod after bone union in congenital pseudoarthrosis of the tibia: a report of two cases.

We report 2 patients with congenital pseudoarthrosis of the tibia who underwent intramedullary Rush rod transfixation through the ankle joint following refracture and nonunion of vascularised fibular grafting 6 and 8 months earlier. After 9 and 5 years, both Rush rods were broken at the level of the ankle joints, while the reconstructed area was solidly united. The growth of the distal tibia increased the distance of the tips of the broken rod and hence the ankle joint motion. The broken tips may damage the articular cartilage and result in valgus deformity of the ankle and limb length discrepancy.

Transfer of ipsilateral fibula on vascular pedicle for treatment of congenital pseudarthrosis of the tibia.

BACKGROUND: Although the use of free vascularized fibula grafts has frequently been reported in the treatment of congenital pseudarthrosis of the tibia, the use of ipsilateral fibula graft on a vascular pedicle is uncommon. We reviewed the long-term results of this procedure in 11 patients. METHODS: The records of 11 patients who underwent transfer of the ipsilateral fibula on a vascular pedicle between 2.1 and 10.8 years of age were retrospectively reviewed. Average follow-up was 11 years after the index procedure. Seven patients had reached skeletal maturity. Clinical records and radiographs were reviewed to determine patient demographics, surgical parameters, union rate, refracture rate, residual deformity, and functional outcome. RESULTS: Eight patients (73%) achieved union at an average of 20.1 months. Additional bone grafting procedures were required in 4 patients with distal nonunions. There were 3 refractures (38%). Four patients eventually underwent amputation, and 1 patient had a persistent nonunion at final follow-up. Residual deformity included tibial valgus and procurvatum deformities, limb length discrepancy, and ankle valgus. Use of the ipsilateral fibula did not seem to increase the risk of ankle valgus. Functional outcomes were good in all but one patient. CONCLUSIONS: Use of the ipsilateral fibula as a pedicle graft provides reasonable results in healing congenital pseudarthrosis of the tibia. Patients should be monitored for the sequelae of this condition, including nonunion, refracture, shortening, and angular deformity, and treated accordingly. LEVEL OF EVIDENCE: Therapeutic Level IV.

A neglected case of congenital pseudarthrosis of tibia.

Congenital pseudarthrosis of the tibia (CPT) is a rare malformation. It was first described by Hatzoecher in 1708. Treatment options of the congenital pseudarthrosis of tibia are variable and challenging. Various forms of bone grafts such as autologous iliac bone graft or free vascularised fibular graft, bracing, electrical stimulation, external fixators including Ilizarov technique and internal fixation with rods and plates are used. Here we represent a case of congenital pseudarthrosis of the tibia (CPT) of a 15 year-old boy, a shopkeeper hailing from Barhatta, Netrokona and diagnosed by history, clinical examination and x-ray. He was treated by Ilizarov technique and follow up was done for a period of 1 year. Complete union was achieved with correction of angulation and shortening.

Use of an intramedullary Kirschner wire for treatment of congenital pseudarthrosis of the tibia in children.

Congenital pseudarthrosis of the tibia remains one of the most difficult, challenging conditions in pediatric orthopedics. The purpose of this study was to evaluate the long-term results of a technique consisting of excision of the pseudarthrosis, autologous bone grafting, and insertion of an intramedullary Kirschner wire into the tibia. Twenty-nine consecutive patients with congenital pseudarthrosis of the tibia were treated with this technique between 1984 and 2004, and the results were retrospectively reviewed and classified into three levels: good, fair, and poor. Complications were also noted. There were 13 patients (44.8%) who had fibular pseudarthrosis. Sixteen patients (52.2%) had primary union at the site of the tibial pseudarthrosis. Refracture occurred in 17 children (58.6%). Twenty-one children (72.4%), despite healed pseudarthrosis, still had residual valgus angulation at the ankle. Twenty-two patients (75.9%) had a residual limb-length discrepancy of greater than 3 cm. At the final follow-up, there were good results in four patients (13.8%), fair results in 12 patients (41.4%), and poor results in 13 patients (44.8%). This technique produced a relatively satisfactory long-term functional outcome, and should be considered in the management of congenital pseudarthrosis of the tibia.

Biologic characteristics of fibrous hamartoma from congenital pseudarthrosis of the tibia associated with neurofibromatosis type 1.

BACKGROUND: Fibrous hamartoma is a key pathologic component of congenital pseudarthrosis of the tibia, a challenging and disabling bone disorder. We investigated the biologic characteristics of fibrous hamartoma cells in order to better understand the pathogenesis of this rare disease. METHODS: Fibrous hamartoma tissues were surgically excised at the time of osteosynthesis from seven patients with congenital pseudarthrosis of the tibia associated with neurofibromatosis type 1. Distal tibial periosteum was also harvested as control tissue during tibial derotation osteotomy from two other patients with cerebral palsy and one patient with idiopathic internal tibial torsion. Fibroblast-like cells were enzymatically dissociated and cultured from these tissues. Immunophenotypes were investigated for positive (CD44 and CD105) and negative (CD45 and CD14) mesenchymal lineage cell markers, and the mRNA expressions of bone morphogenetic protein(BMP)-2, BMP-4, and their receptors were assayed by reverse transcription-polymerase chain reaction. After rhBMP-2 treatment, the changes in alkaline phosphatase activity, and in the mRNA expressions of type-I collagen (COL1A1), alkaline phosphatase, and osteocalcin genes, were assayed with use of an RNase protection assay. The mRNA expressions of receptor activator of nuclear factor-kappa B ligand (RANKL) and osteoprotegerin (OPG) were quantitatively assayed with use of real-time RT-PCR. Osteoclastic differentiation of RAW(264.7) cells in coculture with fibrous hamartoma cells was evaluated. RESULTS: All fibrous hamartoma and tibial periosteal cells tested were CD44+/CD105+/CD45-/CD14- and expressed the mRNAs of BMP-2, BMP-4, and their receptors. The baseline mRNA expressions of COL1A1, alkaline phosphatase, and osteocalcin genes in the fibrous hamartoma cells were diverse. These gene expressions were upregulated by BMP treatment in tibial periosteal cells but did not change or were downregulated in fibrous hamartoma cells. Fibrous hamartoma cells expressed higher levels of RANKL and lower levels of OPG than did tibial periosteal cells. Coculture with fibrous hamartoma cells enhanced osteoclastic differentiation of RAW(264.7) cells. CONCLUSIONS: Fibrous hamartoma cells maintain some of the mesenchymal lineage cell phenotypes, but do not undergo osteoblastic differentiation in response to BMP. They are more osteoclastogenic than are tibial periosteal cells.

Periosteal grafting for congenital pseudarthrosis of the tibia: a preliminary report.

UNLABELLED: The results of treatment of congenital pseudarthrosis of the tibia (CPT) are frequently unsatisfactory because of the need for multiple operations for recalcitrant nonunion, residual deformities, and limb-length discrepancies (LLD). Although the etiology of CPT is basically unknown, recent reports suggest the periosteum is the primary site for the pathologic processes in CPT. We hypothesized complete excision of the diseased periosteum and the application of a combined approach including free periosteal grafting, bone grafting, and intramedullary (IM) nailing of both the tibia and fibula combined with Ilizarov fixation would improve union rates and reduce refracture rates. We retrospectively reviewed 20 patients at two centers. The minimum followup was 2 years (mean, 4.3 years; range, 2-10.7 years). Union was achieved after the primary operation in all patients. Ten refractures occurred in eight of the 20 patients (two each in two patients, one each in six patients). Seven patients underwent seven secondary surgical procedures to simultaneously treat refracture and angular deformities. We used bisphosphonate as adjuvant therapy in three patients with refracture without subsequent refracture. We performed no amputations in these 20 patients. All patients were braced through skeletal maturity. Combining periosteal and bone grafting, IM nailing, and Ilizarov fixation is an effective treatment. IM nailing decreases the severity of subsequent fracture. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Vascular changes in the periosteum of congenital pseudarthrosis of the tibia.

The etiology and the pathogenesis of congenital pseudarthrosis of the tibia (CPT) are still unknown. The affected tibia exhibits insufficient mechanical strength and osteogenetic capability. CPT is frequently associated with neurofibromatosis type 1 (NF1; von Recklinghausen's disease); however, both diseases have not yet been linked pathogenetically. This study presents the pathomorphologic findings of CPT under special consideration of NF1. Therefore, samples from patients operated on for CPT (n = 4) with (n = 3) and without (n = 1) neurofibromatosis were investigated by light microscopy, immunohistochemistry, and electron microscopy. The most striking finding in all patients was thickened periosteum with accumulation of nerval cells surrounding small arteries, causing subtotal or complete obliteration. In conclusion, impaired vascularization can result in decreased osteogenic capabilities. The similarity of ultrastructural findings in the abnormal periosteum and in skin neurofibromas of neurofibromatosis patients may indicate a pathogenetic association of both diseases.

Use of an intramedullary rod for the treatment of congenital pseudarthrosis of the tibia. Surgical technique.

BACKGROUND: The treatment of congenital pseudarthrosis of the tibia remains difficult and controversial. The purpose of this study was to evaluate the long-term results of a technique consisting of excision of the pseudarthrosis, autologous bone-grafting, and insertion of a Williams intramedullary rod into the tibia. METHODS: Twenty-one consecutive patients with congenital pseudarthrosis of the tibia were managed with this technique between 1978 and 1999, and the results were retrospectively reviewed. The mean age of the patients at the time of the latest follow-up was 17.2 years (range, seven to twenty-five years), and the mean duration of postoperative follow-up was 14.2 years (range, three to twenty years). RESULTS: Initial consolidation occurred in eighteen of the twenty-one patients. Refracture occurred in twelve patients; five fractures healed with closed treatment, five healed after an additional surgical procedure, and two ultimately required amputation. Ten patients had an ankle valgus deformity after tibial union. Eleven patients had a residual limb-length discrepancy of >2 cm; six required a contralateral distal femoral and/or proximal tibial epiphyseodesis, two had a tibial lengthening, and one used a shoe-lift. Five patients had an amputation: two, because of a recalcitrant fracture; two, because of a limb-length discrepancy (6 and 9 cm); and one, because of a chronic lower-extremity deformity. CONCLUSIONS: This technique produced a satisfactory long-term functional outcome in sixteen of twenty-one patients and should be considered for the management of congenital pseudarthrosis of the tibia.

Use of an intramedullary rod for treatment of congenital pseudarthrosis of the tibia. A long-term follow-up study.

BACKGROUND: The treatment of congenital pseudarthrosis of the tibia remains difficult and controversial. The purpose of this study was to evaluate the long-term results of a technique consisting of excision of the pseudarthrosis, autologous bone-grafting, and insertion of a Williams intramedullary rod into the tibia. METHODS: Twenty-one consecutive patients with congenital pseudarthrosis of the tibia were managed with this technique between 1978 and 1999, and the results were retrospectively reviewed. The mean age of the patients at the time of the latest follow-up was 17.2 years (range, seven to twenty-five years), and the mean duration of postoperative follow-up was 14.2 years (range, three to twenty years). RESULTS: Initial consolidation occurred in eighteen of the twenty-one patients. Refracture occurred in twelve patients; five fractures healed with closed treatment, five healed after an additional surgical procedure, and two ultimately required amputation. Ten patients had an ankle valgus deformity after tibial union. Eleven patients had a residual limb-length discrepancy of >2 cm; six required a contralateral distal femoral and/or proximal tibial epiphyseodesis, two had a tibial lengthening, and one used a shoe-lift. Five patients had an amputation: two, because of a recalcitrant fracture; two, because of a limb-length discrepancy (6 and 9 cm); and one, because of a chronic lower-extremity deformity. CONCLUSIONS: This technique produced a satisfactory long-term functional outcome in sixteen of twenty-one patients and should be considered for the management of congenital pseudarthrosis of the tibia.

Residual challenges after healing of congenital pseudarthrosis in the tibia.

The purpose of the current study was to evaluate the clinical results of the Ilizarov bone transport method in the treatment of congenital pseudarthrosis in the tibia. In seven patients operated on between 2.6 and 7.8 years of age, primary healing of the pseudarthrosis was achieved in all patients (after additional bone grafting in two patients). Within a followup of 6 to 8 years, major complications occurred in all patients. Five refractures occurred, and in one patient the refracture did not heal. At the last followup, axial deformities and an abnormal malalignment test with lateral mechanical axis deviation of 10 mm or greater was found in all patients. Three patients had leg length inequality of 20 mm or more. The Ilizarov bone transport method is useful in achieving primary healing in congenital pseudarthrosis of the tibia, but residual challenges with secondary reconstructive surgery caused by refracture and postoperative deformities must be expected.

Congenital pseudoarthrosis of the tibia treated with low-intensity pulsed ultrasound stimulation (LIPUS).

A 16-year-old Japanese boy was admitted to our institution in September 2000 because no apparent callus had appeared around a fracture after 6 weeks of cast fixation. Physical examination revealed a tenderness of the right lower leg, and multiple small subcutaneous tumors and café-au-lait spots in extremities and trunk. Radiographs showed the fracture of the right lower tibia with bony sclerosis and a localized fusiform osteolytic lesion at the fracture site. The affected tibia bowed anteriorly and the medullary space in the lower tibia was narrow. A diagnosis of Boyd type IV congenital pseudoarthrosis of the tibia was made. Treatment with low-intensity pulsed ultrasound (US) stimulation (LIPUS) was administered for 20 min/day, and a nonweight-bearing gait was continued with a cast or brace fixation. At 6 months after the treatment, a small amount of bridging callus was seen. We continued the treatment for 1 year until the solid fusion was observed on radiographs and the patient started full-weight-bearing.

Tibial shortening for correction of leg length discrepancy and deformity: a new technique.

Where length discrepancy occurs in the skeletally mature lower leg, there may be a benefit in using the technique of tibial shortening. Existing techniques have not been widely adopted and are associated with a high incidence of soft tissue complications. We describe a technique of progressive shortening, which we believe is a safe method, having adapted this from techniques for dealing with traumatic bone loss.