Internal fixation after fracture or osteotomy of the femur in young children with polyostotic fibrous dysplasia

Surgical correction of valgus deformities of the knee in Polyostotic Fibrous Dysplasia

Coxa vara and shepherd's crook deformity represent the most common femoral deformities in patients affected by polyostotic fibrous dysplasia (PFD) and McCune Albright syndrome (MAS). The tibia is also commonly affected, with antero-medial bowing and valgus deformity. Surgical treatment of these deformities are technically demanding and, in most cases, intramedullary nails are the preferred method to stabilize corrective osteotomies. Genu valgus may also be present, as a residual defect after the surgical correction of the aforementioned deformities. The aim of our study was to report the outcomes obtained in five patients with PFD or MAS operated on for complex deformities of the lower limbs with an associated residual genu valgum greater than 15°. It was surgically treated by distal femoral or proximal tibial osteotomy stabilized with a screw plate. The osteotomy was performed distal to the intramedullary nail in femurs, while it was performed after removing the intramedullary nail in the proximal metaphysis of the tibia. In latter cases, the intramedullary device was reinserted at least 6 months after surgery. At follow-up, the femoro-tibial angle was corrected in all cases and the patients were satisfied with the final result. Two patients showed mild limping, unrelated to the alignment of the knee. In our opinion, residual valgus deformities of the lower limb greater than 15 degrees should be corrected to improve function and cosmetic appearance of these patients. The osteotomy of the distal femur or of the proximal tibia stabilized by a screw-plate represent the treatment of choice for the correction of these deformities.

Intramedullary Nailing for Lower Limb Polyostotic Fibrous Dysplasia in Children: A Long-term Follow-up Study

BACKGROUND

In children, intramedullary nailing (IN) has been proposed as the best treatment when the femur and tibia are totally affected by fibrous dysplasia (FD). However, in younger children IN must be repeated to maintain stabilization of the affected skeletal segment during growth. We report the long-term results in a cohort of patients in whom more than two-thirds of cases had IN repeated during growth.

METHODS

Twenty-nine femurs and 14 tibias totally affected by FD were treated by IN in 21 patients with polyostotic FD and McCune-Albright syndrome. Thirteen patients with 35 femoral and tibial deformities had a painful limp whereas 8 presented fractures. The patients had their first IN at a mean age of 9.26±2.68 years (range: 4 to 14 y). IN was repeated during growth in the younger patients, and all the patients underwent a mean of 2.13 femoral and 1.50 tibial IN per limb. The last IN was performed at a mean age of 16.42±1.95 years (range: 11 to 19 y). Titanium elastic nails and adult humeral nails were used in younger children, whereas adult femoral cervicodiaphyseal and interlocking tibial nails were used in older children and adolescents. At the latest follow-up, the patients were evaluated with a clinicoradiographic scale. All the data were statistically analyzed.

RESULTS

The mean length of follow-up from the last IN was 6.47±3.10 years (range: 3 to 14 y), and the mean age of the patients at follow-up was 22.85±3.53 years (range: 14 to 29 y) when lower limbs were fully grown in all but 1 patient. Satisfactory long-term results were obtained in about 81% of our patients, while complications occurred in 32.5% of the 43 cases.

CONCLUSION

Lower limb IN-that was repeated in younger children during growth-provided satisfactory long-term results in most of our patients, with fracture and deformity prevention and pain control, regardless of the high rate of complications that mainly affected the femoral cases. Missing scheduled follow-ups was the main predictor of a poor result.

LEVEL OF EVIDENCE

Level IV-case series.

Polyostotic Fibrous Dysplasia Complicated by Pathological Fracture of Right Femoral Shaft with Nonunion: A Case Report

Introduction

Fibrous dysplasia is a benign fibrous bone tumor that accounts for 5% to 10% of benign bone tumors. It can manifest as simple fibrous dysplasia (70%–80%), polyostotic fibrous dysplasia (20%–30%), with approximately the same incidence in men and women. We report a patient with a rare case of multiple fibrous dysplasia combined with proximal femoral shepherd deformity with pathological fracture of the femoral shaft complicated by nonunion. It is necessary to understand the disease in more detail to avoid overtreatment of benign lesions or misdiagnosis of malignant tumors and other diseases.

Case presentation

A 58-year-old man with polyostotic fibrous dysplasia, bilateral proximal femur deformity, Shepherd’s angle deformity, right femoral shaft pathological fracture complicated by nonunion, we under fluoroscopy, in the obvious proximal fracture, take osteotomy, and process the shape of the cut bone fragment to adapt it to the corrected force line, and then restore it back to its original position, using intramedullary nailing technology complete the operation. Three months after the operation, he came to the hospital for re-examination, and an X-ray of the right femur was taken. It was found that the fractured end had a tendency to heal. The patient was instructed to gradually bear weight. After six months of re-examination, the patient could walk with a walker. One year after the operation, the patient could walk without a walker and take care of himself at home. However, there was still stretch-like pain in the right lower back, but it was tolerable.

Conclusions

For patients with polyostotic fibrous dysplasia combined with proximal femoral shepherd deformity and pathological fracture of the femoral shaft with nonunion, osteotomy combined with intramedullary nailing is a simple and convenient way to correct the deformity and obtain correct fracture alignment.

Surgical treatment of femoral deformities in polyostotic fibrous dysplasia and McCune-Albright syndrome: A literature review

BACKGROUND

Surgical correction of femoral deformities in polyostotic fibrous dysplasia (PFD) or McCune-Albright syndrome (MAS), such as coxa vara or shepherd’s crook deformity, is a challenge.

AIM

To evaluate the treatment of patients with femoral deformities caused by PDF or MAS treated by osteotomies and stabilized with different methods, by analyzing the most relevant studies on the topic.

METHODS

A literature search was performed in Medline database (PubMed). Articles were screened for patients affected by PFD or MAS surgically managed by osteotomies and stabilized with different methods.

RESULTS

The initial search produced 184 studies, with 15 fulfilling the eligibility criteria of our study. Selected articles (1987-2019) included 111 patients overall (136 femurs).

CONCLUSION

Based on our results, the preferred method to stabilize corrective osteotomies is intramedullary nailing with neck cross pinning. When the deformity is limited to the proximal part of the femur, a screw or blade plate may be used, although there is a high risk of fracture below the plate. When the femur is entirely involved, a two-stage procedure may be considered.

Increasing serum alkaline phosphatase is associated with bone deformity progression for patients with polyostotic fibrous dysplasia

BACKGROUND

Fibrous dysplasia (FD) is a rare bone disorder in which normal intramedullary bone is replaced by fibro-osseous tissue, which is complicated by the progression of Shepherd's crook deformity. How to predict the progression of Shepherd's crook deformity is still a challenging for the orthopedic surgeon.

METHODS

A total of 159 cases were reviewed in the retrospective study between January 2000 and September 2016. Clinical and monitoring data were collected. We analyzed the correlationship between the bone turnover markers and other parameters (age, gender, FD type, deformity, BMI, and lesion location).

RESULTS

Age, gender, lesion location, lesion type, and shepherd's crook deformity had a close relationship with preoperative ALP level in the univariate analysis, and the multivariate analysis showed age, gender, lesion type, and shepherd's crook deformity had the significant relationship with the preoperative serum ALP level. The surgery could remove the bone lesion and suppressed the abnormal bone metabolism. Furthermore, the preoperative ALP level of FD patients with the shepherd's crook deformity was obviously higher than that without deformity, and the preoperative calcium and phosphorus levels of FD patients with deformity were significantly lower than that without deformity. Notably, for some patients with progression of the shepherd's crook deformity during the follow-up, ALP increased to the high level and at that time X-ray showed the shepherd's crook deformity severely progressing.

CONCLUSIONS

PFD with higher serum ALP level has obvious tendency to progress severely, and risk factors of progression to the deformity are the condition of bony metabolism and FD type. The deformity of PFD may be related to high speed of bone turnover, which is exactly reflected by the levels of serum ALP and calcium. Evaluation of patients with FD should include a thorough evaluation of calcium/phosphate metabolism and bone turnover.

Treatment of diaphyseal pathological fractures in children with monostotic fibrous dysplasia using cortical strut allografts and internal plating: A retrospective clinical study

Children with fibrous dysplasia (FD) chronically suffer from pain, pathological fractures, and limb deformities. The most effective methods for managing the associated pathological fractures remain controversial. The purpose of this study was to evaluate the clinical results of the treatment of diaphyseal pathological fractures in children with monostotic fibrous dysplasia (MFD) using cortical strut allografts and internal plating.We retrospectively analyzed outcomes in nine children (5 boys, 4 girls) with diaphyseal pathological fractures due to MFD, who were treated with cortical strut allografts and internal plating (6 femoral fractures and 3 humeral fractures) between July 2007 and November 2012. The median age of patients in our study was 10 years (range 6-14 years). The fracture healing time, pain, extremity function, refracture, graft resorption, and complications were recorded to evaluate treatment effects.The median time of follow-up was 69 months (range 60-75 months). All patients had good postoperative fracture healing with a median healing time of 14 weeks (range 12-16 weeks). None experienced refracture, graft resorption, nerve injury, or limitation of extremity function or other complications. The fixation remained stable in all patients, with no evidence of loosening screws after surgery.In pediatric patients, the described surgical approach is an effective and reliable treatment method for diaphyseal pathological fractures caused by MFD. Cortical strut allografts, which act as biological bone plates, can provide good mechanical support while increasing the rate of fracture union.

Individualized approach to the surgical management of fibrous dysplasia of the proximal femur

BACKGROUND

Fibrous dysplasia of the proximal femur presents with heterogeneous clinical manifestations dictating different surgical approaches. However, to date there are no clear recommendations to guide the choice of surgical approach and no general guidelines for the optimal orthopedic management of these lesions. The objective of this study was to evaluate treatment outcomes of angled blade plates and intramedullary nails, using as outcome indicators revision-free survival, pain, function and femoral neck-shaft-angle. Based on a review of published literature and our study findings, we propose a treatment algorithm, taking into account different factors, which may play a role in the selection of one surgical approach over another.

METHODS

Data were evaluated in thirty-two patients (18 male) from a combined cohort from the Netherlands and Austria, who had a surgical intervention using an angled blade plate (n = 27) or an intramedullary nail (n = 5) between 1985 and 2015, and who had a minimal follow-up of one year. The primary outcome was success of the procedure according to the revised Henderson classification. Secondary outcomes, which were assessed at one year and at the end of follow-up included: function (as measured by walking ability), pain and change in femoral neck-shaft angle over time.

RESULTS

Analysis of data showed that revision-free survival was 72% after a median follow-up of 4.1 years. Revision was necessary in two patients for structural failure due to a fracture distal to an angled blade plate and in 7 patients due to angled blade plate-induced iliotibial tract pain. At the end of follow-up 91% of all patients had good walking ability and 91% were pain free. There was no significant postoperative change in femoral neck shaft angle.

CONCLUSION

Our data show that fibrous dysplasia of the proximal femur can be adequately and safely treated with angled blade plates or intramedullary nails, providing these are used according to specific characteristics of the individual patient. Based on published literature and our own experience, we propose an individualized, patient-tailored approach for the surgical management of fibrous dysplasia of the proximal femur.

Ti-24Nb-4Zr-8Sn Alloy Pedicle Screw Improves Internal Vertebral Fixation by Reducing Stress-Shielding Effects in a Porcine Model

To ensure the biomechanical properties of Ti-24Nb-4Zr-8Sn, stress-shielding effects were compared between Ti-24Nb-4Zr-8Sn and Ti-6Al-4V fixation by using a porcine model. Twelve thoracolumbar spines (T12–L5) of 12-month-old male pigs were randomly divided into two groups: Ti-24Nb-4Zr-8Sn (EG, n = 6) and Ti-6Al-4V (RG, n = 6) fixation. Pedicle screw was fixed at the outer edge of L4-5 vertebral holes. Fourteen measuring points were selected on the front of transverse process and middle and posterior of L4-5 vertebra. Electronic universal testing machine was used to measure the strain resistance of measuring points after forward and backward flexion loading of 150 N. Meanwhile, stress resistance was compared between both groups. The strain and stress resistance of measurement points 1, 2, 5, 6, 9, and 10–14 in Ti-24Nb-4Zr-8Sn fixation was lower than that of Ti-6Al-4V fixation after forward and backward flexion loading (P < 0.05). The strain and stress resistance of measurement points 3, 4, 7, and 8 was higher in Ti-24Nb-4Zr-8Sn fixation than that of Ti-6Al-4V fixation (P < 0.05). Stress-shielding effects of Ti-24Nb-4Zr-8Sn internal fixation were less than that of Ti-6Al-4V internal fixation. These results suggest that Ti-24Nb-4Zr-8Sn elastic fixation has more biomechanical goals than conventional Ti-6Al-4V internal fixation by reducing stress-shielding effects.

Treatment of shepherd's crook deformity in patients with polyostotic fibrous dysplasia using a new type of custom made retrograde intramedullary nail: a technical note

AIMS

The severe form of coxa vara, the 'shepherd's crook deformity', is always a consequence of a locally extensive form of polyostotic fibrous dysplasia (or McCune-Albright syndrome). Treatment of this deformity is a challenge. The soft bone does not tolerate any implant that depends on the stability of the cortical bone (like plates or external fixators). Intramedullary nails are the most appropriate implants for stabilisation, but if they are inserted from the greater trochanter, they cannot correct the varus deformity enough.

PATIENTS AND METHODS

We have developed a special intramedullary nail that can be inserted from the osteotomy site and can be driven retrograde into the femoral neck in an appropriate valgus position. We have operated 15 legs in 13 patients. The average age at surgery was 14 years and 5 months (6 to 28.9). In all, 11 femora had been operated before (unsuccessfully) with various implants.

RESULTS

The average follow-up was 54.2 months (7 to 132). The average correction of the neck/(distal) shaft angle was 57.5° (10° to 80°) ( = 72.8%). While pre-operatively none of the patients was able to walk without aid, at follow-up only one patient was unable to walk, three used the aid of crutches because of tibial lesions and one patient had an increased external rotation of the leg. At follow-up, most patients were free of pain. One implant broke and had to be replaced.

CONCLUSION

This new operative method offers the possibility of efficient correction and stabilisation of this severe and difficult deformation.