Guided growth for pathological physes: radiographic improvement during realignment

Rigid intramedullary nailing of lower limb segments in children and adolescents with metabolic bone disease

Children and adolescents with metabolic bone disease present to the orthopedic surgeon with pain, fractures (which may be impending), and deformity. Different modalities of orthopedic management are available. Scant literature exists on the use of rigid intramedullary nailing in this population. This study sought to evaluate the utilization of this treatment modality in the pediatric cohort, focusing on indications, techniques, and outcomes of the procedures. A retrospective review was performed over an 11-year period at a single tertiary pediatric institution in the UK. Medical records and radiographs were reviewed. Preoperative surgical and medical management, time to bony union, and complications were specifically ascertained. Twenty-seven patients (63 lower limb segments) had rigid intramedullary nailing over the specified period. The majority of patients had an underlying diagnosis of osteogenesis imperfecta or fibrous dysplasia (including McCune Albright Syndrome). Surgical indications included acute fractures, prophylactic stabilization, previous nonunion and malunions, deformity correction, and limb lengthening. All fractures healed and deformity correction was successful. In one patient, delayed union occurred after deformity correction and was successfully treated with dynamization. Fractures healed faster than corrective osteotomies. Complications included implant prominence, cortical penetrance, and screw loosening. Nonunion occurred with limb lengthening in one patient. Rigid intramedullary nailing is a safe and effective method of treatment for lower limb fractures and deformities in children and adolescents. This technique is, therefore, recommended for patients with metabolic bone disease. However, care must be taken in preoperative surgical planning and a multidisciplinary approach should be utilized.

Hemiepiphysiodesis Corrects Lower Extremity Coronal Plane Deformity in Children with Skeletal Dysplasia Irrespective of Intra-Articular Malalignment

Background

Skeletal dysplasias (SkD) are a rare group of disorders characterized by abnormal growth and development of bone and cartilage, often causing limb deformity. Many patients also have ligamentous instability that can accentuate the malalignment. This ligamentous instability can present either a generalized ligamentous laxity or focal coronal plane intra-articular malalignment. Temporary hemiepiphysiodesis (HE) is a commonly employed minimally invasive surgical technique for correcting coronal plane limb deformities. This study evaluated the effectiveness of HE in the correction of knee coronal plane deformity in children with SkD and the correlation of concurrent joint laxity.

Methods

A retrospective cohort study was conducted to evaluate radiological outcomes of HE for coronal plane knee deformities in patients with SkD (aged <18 years) who had surgery between January 1, 2008 and December 31, 2020. Changes in distal femoral and proximal tibial mechanical angles, and knee joint line congruence angles (JLCA) prior to HE and at the final follow-up were analyzed. An increased JLCA of ≥±2° was considered a knee with ligamentous instability. Preoperative and postoperative patient-reported pain status was recorded.

Results

Fifty-six tibial and 42 femoral HE procedures in 32 children (mean age at HE: 9.8 ± 2.8 years) were included. The deformity was fully corrected in 23/32 (72%) children, at an average annual rate of 6.3° at the distal femur and 3.3° at the proximal tibia, over 21.9 ± 12.6 months. The overall pre-HE JLCA improved by an average of 5.3° (P < .05). The improvement was more pronounced in varus knees (n = 45; P < .05) than valgus knees (n = 12; P = .11) but regardless of the severity of joint instability, pre-HE JLCA did not impede the rate of femoral (r = -0.22) or tibial (r = -0.21) corrections. Preoperative pain was reported by 78% of patients whereas only 25% of patients reported pain postoperatively at the final follow-up (mean follow-up: 26.4 ± 13.5 months).

Conclusions

The presence of coronal plane intra-articular malalignment did not affect the rate and the magnitude of correction with HE in this cohort. Coronal plane deformities and JLCA improve with deformity correction by HE in children with SkD.

Key Concepts

(1)Intra-articular malalignment at the knee does not impede the success of hemiepiphysiodesis in children with skeletal dysplasia.(2)While all coronal plane knee deformities improved, a more significant improvement was noted in children with varus than valgus.(3)Joint line congruency angles improved with guided growth for coronal plane deformities.

Level of Evidence

III.

Surgical outcome of angular deformity correction of lower limbs in rickets: a cross-sectional study

PURPOSE

This study aims to compare the functional and radiological outcomes following both guided growth surgery (GGS) and acute corrective osteotomy (ACO) correction of angular deformities in children with rickets.

METHODS

A total of 8 and 7 children who had gradual GGS and ACO correction, respectively, for angular deformities due to rickets from 2002 to 2022 were recalled for follow-up. Demographic data, types of rickets, data on pharmacological treatment, biochemical parameters, recurrence of angular deformity and postoperative complications were obtained from the medical records. A radiographic evaluation of the leg was performed to determine the tibiofemoral angle. For functional evaluation, the Active Scale for Kids (ASK) and Lower Extremity Functional Scale (LEFS) instruments were used for children below and above 15 years old, respectively.

RESULTS

In terms of the tibiofemoral angle, the GGS group documented greater angle changes compared to the ACO group, but the difference was not significant. In terms of functional outcomes, the overall score percentage of both groups was comparable with the GGS group showing a trend of higher score percentage compared to the ACO group. The GGS group presented no complication while 2 neurovascular injuries and 1 implant failure were recorded in the ACO group.

CONCLUSION

Both GGS and ACO procedures resulted in similar radiographic and functional outcomes for the treatment of rickets in children. GGS may be advantageous in terms of reducing complications of surgery. Nevertheless, the choice of surgical intervention should be made based on the patient's circumstances and the surgeon's preference.

Epiphyseal-entry cannulated screws for temporary guided growth of the knees: a retrospective review of 89 cases

Guided growth affects the physis in children to produce a desired effect. Several devices achieve alteration of growth, including staples, plates, and screws. Complications can include device failures, failure to modulate growth as expected, and unintended physeal arrest. We present the results of a unique technique designed to minimize these complications. This was a retrospective review of guided growth at the knee at a single institution utilizing cannulated screws with epiphyseal-entry points. Each case was reviewed to determine the presence of complications related to guided growth, including implant breakage, implant pull-out or pull-through, iatrogenic physeal arrest, failure to modulate growth, and the incidence of revision surgeries. There were 89 patients who had 146 epiphyseal-entry guided growth procedures with a total of 221 4.5 mm cannulated screws. There were no iatrogenic physeal arrests. Five (2.26%) screws in 4 (4.49%) patients had either a broken screw or screw pull-out/pull-through requiring revision procedures. Three patients had osteotomies after skeletal maturity. Four had revision-guided growth for other reasons: 2 due to a lack of timely follow-up, 1 for iatrogenic genu varum without implant failure, and 1 due to recurrent deformity after implant removal. Revision procedures were unanticipated in 6 (6.74%) patients. This study describes a technique for placing cannulated screws at the knee with epiphyseal starting points. Our rate of complications and number of revision surgeries compare favorably with those noted for other techniques. Guided growth using epiphyseal-entry cannulated screws is a safe, effective option for most patients.

Multi-segment osteotomy with interlocking intramedullary nail fixation in the treatment of lower limb deformity in older children with hypophosphatemic rickets

Objective

Malformations of the lower limbs caused by hypophosphatemic rickets in older children are mostly complex, occurring on multiple planes without a single apex and showing arcuate bending of the diaphysis combined with torsion deformity, and are difficult to correct. This study retrospectively investigated the effect of and indicators for multi-segment osteotomy with interlocking intramedullary nail fixation in the treatment of bony deformity caused by hypophosphatemic rickets.

Methods

The clinical data of 21 hypophosphatemic rickets patients seen between August 2007 and March 2022 were collected. The age range of the patients at the first surgery was 11 years and 1 month old to 15 years and 3 months old, with an average age of 12 years and 8 months. There were 6 males and 15 females. All patients had abnormal alignment of their lower limbs, with 32 limbs having varus deformity and 10 limbs having valgus deformity.

Results

A total of 67 surgeries were performed across the 21 patients, including 24 cases of femoral osteotomy with antegrade intramedullary nail fixation, 6 cases of femoral osteotomy with retrograde intramedullary nail fixation, and 20 cases of tibial osteotomy with interlocking intramedullary nail fixation. A total of 34 limbs eventually underwent interlocking intramedullary nail fixation, 9 with genu valgum and 25 with genu varus. All 21 patients were followed up for a period of 14∼96 months, with an average of 42.6 months. The ends of the osteotomies achieved bony union in 4-9 months (average 6.8 months), after which normal weight-bearing walking could be resumed. No infection, vascular or neurological complications, or nonunion occurred. During postoperative follow-up, the alignment the lower limbs passed through zone 1 in 13 limbs, zone 2 in 12 limbs, and zone 3 in 5 limbs. The overall rate of an excellent effect was 83.3%.

Conclusion

For lower limb deformity caused by hypophosphatemic rickets in older children, multi-segment osteotomy and strong fixation with interlocking intramedullary nails can achieve good correction outcomes.

Effective time, correction speed and termination time of hemi-epiphysiodesis in children

In children with asymmetric growth on the medial and lateral side of limbs, if there still remains growth potential, the guided growth technique of hemi-epiphysiodesis on one side of the epiphysis is recognized as a safe and effective method. However, when the hemi-epiphysiodesis start to correct the deformities, how many degrees could hemi-epiphysiodesis bring every month and when to remove the hemi-epiphysiodesis implant without rebound phenomenon are still on debate. This article reviews the current studies focus on the effective time, correction speed and termination time of hemi-epiphysiodesis.

The Evolution of Guided Growth for Lower Extremity Angular Correction

Guided growth is one of the most utilized surgical techniques for managing limb deformity in skeletally immature patients. Our understanding of this technique and the types of implants utilized have evolved over the past century. Many of the known risks of this surgery, such as over-correction, under-correction, and rebound deformity, are the same risks initially described when hemiepiphysiodesis and guided growth techniques were first published. The staple has been a powerful tool for deformity correction but its high rates of implant backout and breakage as well as unpredictable rates of premature physeal closure after removal have contributed to this implant being used less frequently today. Many studies on percutaneous transepiphyseal screws (PETS) are promising but have little follow-up, so the risks of this technique with regard to premature physeal closure are not well understood. Tension band plating is currently the most utilized method. However, in specific patient subgroups, the perioperative complication and failure of correction rates are high. Despite the abundance of literature on these techniques, our understanding of guided growth is still quite limited, as most studies are small and do not follow patients to skeletal maturity. Guided growth surgery also can restore the mechanical axis of the limb while leaving patients with significant residual diaphyseal or peri-articular deformity and the implications of these secondary deformities have not been studied.

Key Concepts

•An understanding of the patient's skeletal maturity and predicted growth remaining is essential prior to performing guided growth surgery.•Regular patient follow-up is critical to prevent over-correction of deformity.•Staples are an effective implant for angular deformity correction but have higher rates of implant backout, breakage, and premature physeal arrest compared to other devices.•Percutaneous transepiphyseal screws can be an effective way to correct angular deformity, but current studies are both small and lack long-term follow-up, which makes it difficult to truly understand the potential risks and complications of this technique.•Tension band plating is a safe and effective treatment for angular deformity correction but the rates of implant breakage and peri-surgical complications in patients with Blount disease are consistently high.

A Comparative Investigation of Chemical Decontamination Methods for In-Situ Cleaning of Dental Implant Surfaces

Surface chemistry evaluation is crucial in assessing the efficacy of chemical decontamination products for titanium implants. This study aimed to investigate the effectiveness of chemical decontamination solutions in cleaning a contaminated dental implant surface and to evaluate the potential of combining Pluronic gel with hydrogen peroxide (NuBone®Clean) by evaluating pellicle disruption and re-formation on implant surfaces. In addition, ensuring safety with in vitro and human testing protocols. X-ray Photoelectron Spectroscopy (XPS) was utilised for surface analysis. All the tested gels had some effect on the surface cleanness except for PrefGel®. Among the tested chemical decontamination candidates, NuBone®Clean demonstrated effectiveness in providing a cleaner titanium surface. Furthermore, none of the tested chemical agents exhibited cytotoxic effects, and the safety assessment showed no adverse events. The results of this study highlight the significance of conducting comprehensive evaluations, encompassing safety and efficacy, before introducing new chemical agents for dental treatments. The findings suggest that NuBone®Clean shows potential as a chemical decontamination solution for implant surfaces. However, further investigation through randomised clinical trials is necessary. By adhering to rigorous testing protocols, the development of safe and efficient chemical decontamination strategies can be advanced, benefiting patients and promoting progress in implant dentistry.

Predictive factors for recurrence after lower limb deformity correction in hypophosphatemic rickets

BACKGROUND

Surgical treatment for severe lower limb deformities in patients with hypophosphatemic rickets has shown satisfactory outcomes. However, the rates of recurrence of deformities after surgical correction were high, and studies on predictive factors of recurrence were limited. This study aimed to determine the predictive factors for the recurrence of lower limb deformities after surgical correction in patients with hypophosphatemic rickets, and the effects of each predictor on the recurrence of deformities.

METHODS

We retrospectively reviewed the medical records of 16 patients with hypophosphatemic rickets aged 5-20 years and who had undergone corrective osteotomies between January 2005 and March 2019. Demographic data from the patients, biochemical profiles, and radiographic parameters were collected. Univariable Cox proportional hazard analyses of recurrence were performed. Kaplan-Meier failure estimation curves for deformity recurrences of potential predictors were created.

RESULTS

A total of 38 bone segments were divided into 2 groups: 8 segments with recurrent deformities and 30 segments without recurrent. The average follow-up time was 5.5 ± 4.6 years. Univariable Cox proportional hazard analyses of recurrence found that an age < 10 years (hazard ratio [HR], 5.5; 95% CI, 1.1-27.1; p = 0.04), and gradual correction by hemiepiphysiodesis (HR, 7.0; 95% CI, 1.2-42.7; p = 0.03) were associated with recurrence after surgery. The Kaplan-Meier failure estimation for deformity recurrences by age at the time of surgery also achieved a statistically significant difference between ages < 10 years and those > 10 years (p = 0.02).

CONCLUSIONS

Identifying predictive factors for the recurrence of lower limb deformities after surgical correction in hypophosphatemic rickets can assist in early recognition, proper intervention, and prevention. We found that an age < 10 years at the time of surgery was associated with recurrence after deformity correction and gradual correction with hemiepiphysiodesis may also be a potential factor affecting the recurrence.

The efficacy of hemiepiphysiodesis for idiopathic knee coronal angular deformity by reconstruction plate and screw: A pilot study

Background

Angular deformities of the lower extremities are among the most common findings in pediatric orthopedics. Alteration of the mechanical axis in the lower extremity affects the cosmetic appearance and may lead to gait disturbances, knee discomfort, patellar maltracking with or without pain, and early joint osteoarthritis. In the current study, we aimed to investigate the efficacy of 3-hole 3.5 mm reconstruction plates in tension-band temporary hemiepiphysiodesis for correcting idiopathic knee coronal angular deformities.

Methods

The surgical procedure was performed using an extraperiosteal tension band plate (a 3-hole reconstruction plate) and two 3.5 mm cortical screws to treat idiopathic knee coronal angular deformity in children. The location of the hemiepiphysiodesis was determined based on the type of angular deformity present. Postoperative follow-ups were conducted through x-rays to measure the medial proximal tibial angle and lateral distal femoral angle of the limbs. Statistical analysis was then performed to evaluate the efficacy of the surgical treatment based on the rate of alignment change exhibited.

Results

The study included 14 patients (25 limbs) with genu valgum deformity who underwent temporary hemiepiphysiodesis on both the distal femur and proximal tibia, with 16 proximal tibias and 15 distal femurs being corrected. The correction rate for genu valgum was found to be 0.59° per month for both proximal tibial and distal femoral hemiepiphysiodesis. Six patients (12 limbs) were also identified with genu varum deformity, and the correction rates for proximal tibial lateral hemiepiphysiodesis and distal femoral lateral hemiepiphysiodesis were 0.85° and 0.15° per month, respectively. During a mean follow-up duration of 11 ± 5.7 months, only one case of physeal plate closure was observed, and there were no other significant complications.

Conclusion

Temporary hemiepiphysiodesis with a 3-hole R-plate and two cortical screws takes advantage of physiological physeal growth to successfully treat idiopathic angular deformities with low complication rates.

Temporary hemiepiphysiodesis using eight-plates for angular deformities of the lower extremities in children with X-linked hypophosphataemic rickets

PURPOSES

Temporary hemiepiphysiodesis (TH) using eight-plates is one of the most frequently performed surgeries for correcting angular deformities of the lower extremities in adolescents. Rarely have studies examined children with X-linked hypophosphataemic rickets (X-LHPR) treated with TH using eight-plates. This study was conducted to investigate the efficacy, the endpoint, and the complications of TH using eight-plates to correct angular deformities of the lower extremities in skeletally immature children.

METHODS

We reviewed a total of 26 children (86 physes, 52 knees) with X-LHPR (mean age of 6.2 years, range from 2 to 13 years) who underwent TH using eight-plate to correct angular deformities of the lower extremities. Radiographs and clinical records of these patients were evaluated for demographic data and related clinical factors.

RESULTS

The average correction of the mechanical lateral distal femoral angle (mLDFA) was 11.7 ± 8.7° (range from 1.0 to 29.7°), and the average correction of the mechanical medial proximal tibial angle (mMPTA) was 8.4 ± 5.0° (range from 0.3 to 16.7°). The mean deformity correction time was 22.7 months (range from 7 to 60 months), and the mean follow-up after eight-plate removal was 43.9 months (range from 24 to 101 months). Overall, 76.9% (20/26 patients) of the angular deformities of the knee were completely corrected and 15.4% (4/26) of the patients received osteotomy surgery. The femoral correction velocity (0.9° per month) was significantly higher than the proximal tibial (0.6° per month) (p = 0.02). The correction velocity of the mLDFA and mMPTA with the TH procedure was faster than that in the absence of intervention (0.9° vs. 0.2°, 0.7° vs. 0.4° per month, p < 0.05). The correction velocity of the mLDFA (1.2° vs. 0.5° per month, [Formula: see text]) and mMPTA (0.7° vs. 0.5° per month, p = 0.04) of patients whose age ≤ five years old was faster than that of patients whose age > five years old. A total of 69.2% (18/26) patients experienced one TH procedure using eight-plates only. Two patients had screw loosening (2/26, 7.7%). One patient (1/26, 3.8%) had a rebound phenomenon after the removal of eight-plate and had the TH procedure again. There was no breakage, infection, physis preclosure, or limited range of movement found in the follow-up.

CONCLUSION

TH using eight-plates is a safe and effective procedure with a relatively low incidence of complication and rebound, and it could be used as part of a streamlined treatment for younger X-LHPR patients with resistant or progressive lower limb deformity despite optimal medical treatment. Early intervention can achieve better results.

CORONAL PLANE GROWTH MODULATION FOR GENU VALGUM IN SKELETAL DYSPLASIA

Objective

To investigate the efficiency and rates of correction by hemiepiphysiodesis using 8-plate to manage genu valgum deformity in children with skeletal dysplasia.

Methods

Eleven children with skeletal dysplasia (three female, eight male; mean age = 10.5 years; age range = 7-13) who underwent temporary hemiepiphysiodesis using 8-plates for genu valgum deformity were retrospectively reviewed. There were nine bilateral cases and two unilateral cases. The mean follow-up time from the index surgery to the final follow-up was 45 (ranging from 24 to 72) months. Radiographical assessment including preoperative and final follow-up measurements of joint orientation angles and mechanical axis deviation (MAD) were conducted.

Results

Deformities were completely corrected in nine lower extremities (45%) and partially corrected in seven extremities (35%). In four extremities of two children with Morquio syndrome, MAD worsened. The correction rate of MAD was 1.25 ± 1.62 mm/mo.

Conclusion

Though hemiepiphysiodesis using 8-plate requires a longer treatment period, it seems to be an effective treatment for correction of genu valgum in children with skeletal dysplasia. Level of Evidence IV, Case Series.

Correction of pediatric angular deformities in lower limbs through guided growth using a novel flexible plate system

INTRODUCTION

Tension band plates (TBP) for guided growth (GG) are the gold standard treatment for angular deformities around the knee. EPIFLEX® is a novel flexible TBP that adjusts to the patient's bone anatomy.

HYPOTHESIS

GG using a flexible TBP produces satisfactory correction rates with minor complications in the pediatric population with angular deformities around the knee.

MATERIALS AND METHODS

A retrospective evaluation of 33 patients (60 knees) treated for genu varum and valgum with hemiepiphysiodesis using a flexible TBP between 2017 and 2020 was performed. The study aimed to assess correction and complication rates; patients who completed treatment were included regardless of the follow-up times after implant removal.

RESULTS

Thirteen females and 20 males with a median age of 10 years were included. The median treatment duration and follow-up were 10 and 22 months. The median monthly rate of change of mLDFA and mMPTA was 0.67° and 0.57°, respectively. A successful correction was achieved in 90% of the cases. There were no cases of infection or implant failure. Four cases presented overcorrection and two undercorrection; no significant relation with deformity or obesity was found.

DISCUSSION

GG using this flexible TBP showed satisfactory correction rates with a low incidence of complications and no implant failure. It provides flexibility through good adaptability to the bone anatomy and mobility of the screws avoiding implant protrusion or breakage.

LEVEL OF EVIDENCE

IV; observational descriptive case series.

Interdisciplinary management of FGF23-related phosphate wasting syndromes: a Consensus Statement on the evaluation, diagnosis and care of patients with X-linked hypophosphataemia

X-linked hypophosphataemia (XLH) is the most frequent cause of hypophosphataemia-associated rickets of genetic origin and is associated with high levels of the phosphaturic hormone fibroblast growth factor 23 (FGF23). In addition to rickets and osteomalacia, patients with XLH have a heavy disease burden with enthesopathies, osteoarthritis, pseudofractures and dental complications, all of which contribute to reduced quality of life. This Consensus Statement presents the outcomes of a working group of the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases, and provides robust clinical evidence on management in XLH, with an emphasis on patients' experiences and needs. During growth, conventional treatment with phosphate supplements and active vitamin D metabolites (such as calcitriol) improves growth, ameliorates leg deformities and dental manifestations, and reduces pain. The continuation of conventional treatment in symptom-free adults is still debated. A novel therapeutic approach is the monoclonal anti-FGF23 antibody burosumab. Although promising, further studies are required to clarify its long-term efficacy, particularly in adults. Given the diversity of symptoms and complications, an interdisciplinary approach to management is of paramount importance. The focus of treatment should be not only on the physical manifestations and challenges associated with XLH and other FGF23-mediated hypophosphataemia syndromes, but also on the major psychological and social impact of the disease.

Feasibility of microwave ablation of the vertebral growth plate for spine growth regulation: a preliminary study

PURPOSE

To explore the feasibility of microwave ablation (MWA) of the vertebral growth plate as a minimally invasive treatment for early-onset scoliosis.

MATERIALS AND METHODS

One side of the L1-L3 vertebral growth plates were ablated using different MWA powers. Ablation safety and size were examined. Subsequently, L1-L3 vertebral growth plates were ablated on one side for 40 s at 20 W. At 2, 4, and 6 weeks after the ablation, growth changes of the spine were observed.

RESULTS

No piglets died during and after ablation, and all had modified Tarlov Grade 5. The safe MWA time (time for safely ablating the vertebral growth plate) was 17.0 ± 1.5 s at 50 W, 23.0 ± 2.3 s at 40 W, 31.0 ± 3.1 s at 30 W, 47.0 ± 3.7 s at 20 W, 70.0 ± 4.2 s at 15 W, and 158.0 ± 5.0 s at 10 W. With power <15 W, the vertebral growth plate could not be effectively ablated within the safe ablation time. Within the safe ablation times, the MWA size on hematoxylin and eosin slices on a transverse diameter was between 7 and 10 mm; and that on longitudinal diameter was mainly determined by the ablation needle length. Moreover, the growth plate and annulus fibrosus on the ablated side grew poorly over time, the vertebral body showed significant wedge-shaped changes, and the spine showed significant unbalanced growth.

CONCLUSION

MWA of the vertebral growth plate can be performed safely when accompanied with appropriate thermometry, and could be a new minimally invasive strategy in regulating spine growth.

Angular Deformities of the Knee in Children Treated with Guided Growth

Introduction:

The guided growth technique is an alternative to corrective osteotomy for treating angular deformities of the extremities. It has the advantage of being minimally invasive and is effective in a growing child. This study reports on the outcome of guided growth technique using a plate in correcting knee angular deformities.

Material and Methods:

We conducted a retrospective study of children with angular deformity of the knee treated by the guided growth technique from January 2010 to December 2015 in a tertiary centre. The guided growth technique was done using either the flexible titanium plate (8-plate) or the 2-hole reconstruction plate. Correction of deformity was assessed on radiographs by evaluating the mechanical axis deviation and tibiofemoral angle. The implants were removed once deformity correction was achieved.

Results:

A total of 17 patients (27 knees) were evaluated. Twenty-two knees (81.5%) achieved complete correction of the deformity. The median age was 4.0 (interquartile range 3.0-6.0) years and the median Body Mass Index (BMI) was 26.0 (25.0-28.0). There were 7 unilateral and 10 bilateral deformities with different pathologies (14 tibia vara, 3 genu valgus). The median rate of correction was 0.71° per month. One patient (1 knee) had screw pull-out and two patients (4 knees) had broken screws in the proximal tibia. Three patients (5 knees) failed to achieve complete correction and were subsequently treated with corrective osteotomies. Out of five patients (8 knees) who were followed-up for at least 12 months after removal of hardware, two had rebound deformities. No permanent growth retardation occurred in our patients.

Conclusion:

Our outcome for guided growth to correct knee angular deformity was similar to other studies. Guided growth is safe to perform in children below 12 years old and has good outcome in idiopathic genu valgus and Langeskiold II for tibia vara. Patients should be observed for recurrence until skeletal maturity following implant removal.

Growth modulation with tension-band plates for the correction of paediatric lower limb angular deformity: current concepts and indications for a rational use

Growth modulation (GM) with tension-band plates (TBPs) by tethering part of the growth plate is an established technique for the correction of angular deformities in children, and it has increasingly supplanted more invasive osteotomies.Growth modulation with TBPs is a safe and effective method to correct a variety of deformities in skeletally immature patients with idiopathic and pathological physes. The most common indication is a persistent deformity in the coronal plane of the knee exceeding 10°, with anterior and/or lateral joint pain, patellofemoral instability, gait disturbance, or cosmetic concerns. GM has also shown good results in patients with fixed flexion deformity of the knee and ankle valgus.This paper reviews the history of the procedure, current indications, and recent advances underlying physeal manipulation with TBPs. Cite this article: EFORT Open Rev 2021;6:658-668. DOI: 10.1302/2058-5241.6.200098.

[Prevalence and predictors of rebound deformity in the frontal plane : A literature review]

The present literature review presents the current state of the art on the prevalence and causes of the rebound phenomenon after successful correction of leg axis deformity using temporary epiphysiodesis in children and adolescents. A total of 20 studies was included by three independent reviewers. The validity of most studies regarding the rebound incidence is limited by a non-standardized follow-up after plate removal, heterogeneous patient groups with a small number of cases, and missing information on the definition of rebound. The rebound incidence in studies without fundamental limitations in study design is on an average about 50% and underlines the clinical relevance of the topic. Only four studies reported reasons or risk factors for the occurrence of a rebound. In particular, a young age at the beginning of treatment with high residual growth potential after implant removal represents an increased rebound risk, which can be minimized by appropriate overcorrection of the leg axis.

Comparison of histomorphometric and radiographic effects of growth guidance with tension-band devices (eight-Plate and FlexTack) in a pig model

Background and purpose - Temporary hemiepiphysiodesis for growth modulation in skeletally immature patients is a long-known technique. Recently the use of tension-band devices has become popular. This study compares 2 tension-band implants (eight-Plate and FlexTack) regarding their effects on the growth plate.Animals and methods - 12 pigs in 2 equally sized groups (A and B) were investigated. The right proximal medial tibia was treated with either eight-Plate or FlexTack. The left tibia of the same pig was treated with the opposite implant. After 9 weeks all implants were removed. Animals in group B were then hosted for another 5 weeks. Histomorphometric analysis of the growth plate was carried out after 9 and 14 weeks, respectively. Radiographs were taken at implantation, removal, and after 14 weeks.Results - Both tension-band devices achieved a statistically significant and clinically relevant growth inhibition, whereas the effect appeared to be more distinct after the use of FlexTack. Implant-related complications or physeal damage was not observed. After implant removal, rebound phenomenon was radiologically observed in all cases. The growth plates treated with eight-Plate showed a paradox reversal of the zonal distributions, with an increase of the proliferative zones at the previously arrested medial aspect of the physis and a decrease laterally.Interpretation - Both eight-Plate and FlexTack proved to be appropriate devices for growth-guiding treatment. The radiographic evaluation showed a change in angular axes after treatment with each implant, while the correction appeared to be faster with FlexTack. The paradox cartilaginous reaction observed after removal of the eight-Plate might be a histopathological correlate for rebound phenomenon.

Blount's disease - an up-to-date insight with contemporary treatment guidelines deduced from critical analysis of a large 146 surgical case series

To elucidate an up-to-date insight and derive clear treatment guidelines for Blount's disease deduced from critical analysis of 146 surgical case series. Cases were presented and analyzed separately under its two basic clinical groups and the author further derived four subcategories under each of these two groups; the first basic group was the early onset clinical variant; infantile tibia vara (ITV) included 56 cases. The second group was the late onset clinical variant; late onset tibia vara (LOTV) included 90 cases. Different operative procedures used for treatment of these cases were proximal tibial osteotomy (PTO), temporary eight-plate proximal lateral tibial hemiepiphyseodesis (PLTH), or medial plateau elevation either on a monomodal or multimodal line of treatment. After a mean follow-up period of ~5 (2-12) years, the results were critically analyzed using case series descriptive analysis. In ITV variant, both PTO and temporary eight-plate PLTH monomodal line of treatment gave satisfactory results for de-novo (stages I, II, and III) subcategory while multimodal line of treatment was needed for achieving satisfactory results for neglected (stages IV, V, and VI) and relapsed subcategories. For LOTV variant, PTO monomodal line of treatment gave satisfactory results when applied for treatment of its de-novo subcategory. The derived treatment guidelines for Blount's disease can be of value for recruiting the most suitable treatment modality for each case entity of the disease, leading to satisfactory outcome with prevention of recurrence.

Leg lengthening and deformity correction in rare bone diseases: a multidisciplinary approach

Congenital and acquired conditions presenting with leg length discrepancy, leg deformity or short stature are not only a challenge for paediatric orthopaedic surgeons in terms of treatment options but may also involve a number of medical specialties due to the complex clinical manifestations of the diseases. Various surgical treatment options are available for these rare genetic diseases, including bone lengthening and growth inhibition techniques for lower limb discrepancy, as well as guided growth and other surgical procedures for correction of angular deformities. Surgical techniques may be similar, but the treatment plans and specific multidisciplinary approaches may differ. The present report is focused on paediatric orthopaedic and multidisciplinary aspects of the treatment of rare bone diseases. We address the clinical presentation of these diseases, gait and surgical procedures for conditions such as achondroplasia, X‑linked hypophosphatemia and osteogenesis imperfecta. We also provide a short overview of other rare bone diseases.

X-Linked Hypophosphatemic Rickets: Multisystemic Disorder in Children Requiring Multidisciplinary Management

X-linked hypophosphatemic rickets (XLH) is the commonest inherited form of rickets. It is caused by an impaired regulation of fibroblast growth factor 23 (FGF23) due to a PHEX gene mutation, which leads to reduced tubular reabsorption of phosphate and renal 1α-hydroxylase activity and increased renal 24-hydroxylase activity. Hypophosphatemia associated with renal phosphate wasting, normal serum levels of calcium, parathyroid hormone, and 25-hydroxyvitamin D represents the main biochemical sign in affected patients. Patients with XLH show rickets and osteomalacia, severe deformities of the lower limbs, bone and muscular pain, stunted growth, and reduced quality of life. However, XLH is a multisystemic disorder requiring multidisciplinary approaches in specialized subdisciplines. Severe complications may occur in patients with XLH including craniosynostosis, hearing loss, progressive bone deformities, dental and periodontal recurrent lesions, and psychosocial distress. Moreover, long-term conventional treatment with active vitamin D metabolites and oral inorganic phosphate salts may cause endocrinological complications such as secondary or tertiary hyperparathyroidism, and adverse events in kidney as hypercalciuria, nephrocalcinosis, and nephrolithiasis. However, conventional treatment does not improve phosphate metabolism and it shows poor and slow effects in improving rickets lesions and linear growth. Recently, some trials of treatment with recombinant human IgG1 monoclonal antibody that targets FGF23 (burosumab) showed significant improvement of serum phosphate concentration and renal tubular reabsorption of phosphate that were associated with a rapid healing of radiologic signs of rickets, reduced muscular and osteoarticular pain, and improved physical function, being more effective for the treatment of patients with XLH in comparison with conventional therapy. Therefore, a global management of patients with XLH is strongly recommended and patients should be seen regularly by a multidisciplinary team of experts.

Does eight-plate epiphysiodesis of the proximal tibia in treating angular deformity create intra-articular deformity?

Aims

Eight-plates are used to correct varus-valgus deformity (VVD) or limb-length discrepancy (LLD) in children and adolescents. It was reported that these implants might create a bony deformity within the knee joint by change of the roof angle (RA) after epiphysiodesis of the proximal tibia following a radiological assessment limited to anteroposterior (AP) radiographs. The aim of this study was to analyze the RA, complemented with lateral knee radiographs, with focus on the tibial slope (TS) and the degree of deformity correction.

Methods

A retrospective, single-centre study was conducted. The treatment group (n = 64 knees in 44 patients) was subclassified according to the implant location in two groups: 1) medial hemiepiphysiodesis; and 2) lateral hemiepiphysiodesis. A third control group consisted of 25 untreated knees. The limb axes and RA were measured on long standing AP leg radiographs. Lateral radiographs of 40 knees were available for TS analysis. The mean age of the patients was 10.6 years (4 to 15) in the treatment group and 8.4 years (4 to 14) in the control group. Implants were removed after a mean 1.2 years (0.5 to 3).

Results

No significant differences in RA (p = 0.174) and TS (p = 0.787) were observed. The limb axes were significantly corrected in patients with VVD (p < 0.001). The change in tibial slope (∆TS) did not correlate ( r = -0.026; p = 0.885) to the plate’s position on the physis when assessed by lateral radiographs.

Conclusion

We were not able to confirm the reported change in the bony morphology of the proximal tibia on AP radiographs in our patient population. In addition, no significant change in TS was detected on the lateral radiographs. A significant correction of the VVD in the lower limb axes was evident. Position of the implant did not correlate with TS change. Therefore, eight-plate epiphysiodesis is a safe and effective procedure for correcting VVD in children without disturbing the knee joint morphology. Cite this article: Bone Joint J 2020;102-B(10):1412–1418.

Disease-specific gait deviations in pediatric patients with X-linked hypophosphatemia

BACKGROUND

X-linked hypophosphatemia (XLH) represents the most common genetic form of rickets featuring profound hypophosphatemia with associated skeletal and non-skeletal manifestations. Early onset gait disturbances contribute strongly to the burden of disease. However, no study has comprehensively characterized naturally occurring gait deviations in pediatric patients with XLH.

RESEARCH QUESTIONS

Can disease-specific gait deviations and potentially influencing factors be identified by gait analysis in non-surgically treated children with XLH?

METHODS

Gait laboratory assessments of 12 pediatric patients with XLH without previous long bone surgery was retrospectively analyzed and compared to age-matched healthy controls. Radiologic and clinical parameters of XLH patients were correlated with kinematic gait variables and gait scores.

RESULTS

Reduced external knee rotation and increased external hip orientation was ubiquitous in children with XLH. Increased lateral trunk lean, or "waddling gait", occurred in five children and was associated with varus knee deformities. Overall, children with XLH showed a reduced Gait Deviation Index (GDI) compared to controls. Radiologic and gait analysis revealed complex combined frontal and torsional deformity of the lower limbs as a common feature in XLH. Higher Body Mass Index (BMI) was associated with both lateral trunk lean and impaired GDI.

SIGNIFICANCE

Gait analysis is feasible to quantify gait deviations and lower limb deformities in pediatric patients with XLH. Specific gait characteristics including internal knee rotation and external hip rotation are common among patients with XLH and contribute to impaired gait scores. Our data suggest the use of gait and deformity data assessment as outcome parameters in future observational and interventional studies. Standardized assessment might contribute to targeted treatments to improve life quality in XLH patients.

HEMIEPIPHYSIODESIS USING EIGHT-PLATE VERSUS BLOUNT STAPLE TO CORRECT GENU VALGUM AND GENU VARUM

Objective:

Our objective is to evaluate whether the use of guided growth with eight-plates is more effective than the use of Blount staples for the correction of the idiopathic genu varum or idiopathic genu valgum.

Methods:

A systematic review (SR) was carried out according to the appropriate methodology for randomized clinical trials (RCTs). We searched seven databases through a previously defined methodology, and we included RCTs, regardless of language, period of publication and status of publication.

Results:

Resulted in 6830 articles retrieved. Of theses, we identified 14 potential eligible studies. but just one RCT was included for the SR. The included RCT compares the eight-plate and the Blount staple and showed no statistically significant difference for the outcomes of time to correct the deformity, postoperative pain after 24 hours and postoperative pain after 72 hours. The study is of low or very low level of evidence to determine the most effective technique. We didn’t find a RCT that compared the correction of the genu varum.

Conclusion:

Good quality randomized clinical trials comparing Blount staples versus eight-plaque must be performed to determine which technique is superior for coronal plane corrections. Level of Evidence I, Systematic review of Level RCTs.

Multidisciplinary patient care in X-linked hypophosphatemic rickets: one challenge, many perspectives

X‑linked hypophosphatemic rickets (XLH, OMIM #307800) is a rare genetic metabolic disorder caused by dysregulation of fibroblast-like growth factor 23 (FGF23) leading to profound reduction in renal phosphate reabsorption. Impaired growth, severe rickets and complex skeletal deformities are direct consequences of hypophosphatemia representing major symptoms of XLH during childhood. In adults, secondary complications including early development of osteoarthritis substantially impair quality of life and cause significant clinical burden. With the global approval of the monoclonal FGF23 antibody burosumab, a targeted treatment with promising results in phase III studies is available for children with XLH. Nevertheless, complete phenotypic rescue is rarely achieved and remaining multisystemic symptoms demand multidisciplinary specialist care. Coordination of patient management within the major medical disciplines is a mainstay to optimize treatment and reduce disease burden. This review aims to depict different perspectives in XLH patient care in the setting of a multidisciplinary centre of expertise for rare bone diseases.

Hemiepiphysiodesis using 2-holed reconstruction plate for correction of angular deformity of the knee in children

Background

This study assesses the outcome of hemi epiphysiodesis with a 2-holed reconstruction plate using the tension band principle in angular deformities of the knee and variables influencing the outcome.

Methods

Prospective study from 2012 to 2016 included 23 children with coronal deformities of the knee joint. IMD, ICD, BMI, mLDFA, mMPTA, mTFA, Mechanical axis deviation, Perpendicular mechanical axis ratio, and screw angle measured. Correction and rate of correction compared with BMI, age, etiology, PMAR and MAD, deformity, a segment of bone and the screw angle.

Results

Total 65 segments operated in 23 children with 40 knees. Out of the total 65, 36 plates were kept in distal femur physis and 29 in the proximal tibial physis. Thirteen knees had genu varum and 27 had genu valgum. The mean age at the time of surgery was 11.25 months. The mean follow-up of 36 months and the average time for correction was 18.64 months. 77.5% correction achieved with ROC maximum in the initial 6 months. ROC in TFA per year were 7.8⁰(femur), 5⁰(tibia), and 12⁰(femur with tibia). Complications included broken implant, screw back out, screw irritation and rebound phenomenon.

Conclusions

2-holed reconstruction plate gives similar correction to that of the 8-plate within a comparable period without additional complications. It has the advantage of being cost effective and readily available. Age, BMI, type of deformity, amount of initial deformity, do not play a significant role in the outcome of correction. Screw placement may have a role in the final correction of the deformity.

Level of evidence

Level 3.

Orthopaedic Manifestations in Turner Syndrome

Turner syndrome is one of the most common chromosomal anomalies occurring in live-born females. It has been extensively reviewed in the medical literature, yet little has been discussed regarding the skeletal manifestations that present to the orthopaedic surgeon. It is important for the orthopaedic surgeon to be familiar with the clinical findings and comorbid conditions in Turner syndrome because they may be the first line of diagnosis when a patient presents for short stature, scoliosis, or slipped capital femoral epiphysis. Recent studies have identified the short stature homeobox gene as the main cause of the skeletal differences in patients with Turner syndrome, affecting longitudinal bone growth. Skeletal deformities including short stature, delayed skeletal maturation, angular deformity of the limbs, spinal deformity, and early-onset osteoporosis have been associated with Turner syndrome. This article will review the skeletal manifestations of Turner syndrome and propose guidelines for the treatment and monitoring of these patients. LEVEL OF EVIDENCE:: Level V.

Rebound Deformity After Growth Modulation in Patients With Coronal Plane Angular Deformities About the Knee: Who Gets It and How Much?

BACKGROUND

With observed success and increased popularity of growth modulation techniques, there has been a trend toward use in progressively younger patients. Younger age at growth modulation increases the likelihood of complete deformity correction and need for implant removal before skeletal maturity introducing the risk of rebound deformity. The purpose of this study was to quantify magnitude and identify risk factors for rebound deformity after growth modulation.

METHODS

We performed a retrospective review of all patients undergoing growth modulation with a tension band plate for coronal plane deformity about the knee with subsequent implant removal. Exclusion criteria included completion epiphysiodesis or osteotomy at implant removal, ongoing growth modulation, and <1 year radiographic follow-up without rebound deformity. Mechanical lateral distal femoral angle, mechanical medial proximal tibial angle, hip-knee-ankle angle (HKA), and mechanical axis station were measured before growth modulation, before implant removal, and at final follow-up.

RESULTS

In total, 67 limbs in 45 patients met the inclusion criteria. Mean age at growth modulation was 9.8 years (range, 3.4 to 15.4 y) and mean age at implant removal was 11.4 years (range, 5.3 to 16.4 y). Mean change in HKA after implant removal was 6.9 degrees (range, 0 to 23 degrees). In total, 52% of patients had >5 degrees rebound and 30% had >10 degrees rebound in HKA after implant removal. Females below 10 years and males below 12 years at time of growth modulation had greater mean change in HKA after implant removal compared with older patients (8.4 vs. 4.7 degrees, P=0.012). Patients with initial deformity >20 degrees had an increased frequency of rebound >10 degrees compared with patients with less severe initial deformity (78% vs. 22%, P=0.002).

CONCLUSIONS

Rebound deformity after growth modulation is common. Growth modulation at a young age and large initial deformity increases risk of rebound. However, rebound does not occur in all at risk patients, therefore, we recommend against routine overcorrection.

LEVEL OF EVIDENCE

Level IV-retrospective study.

Clinical practice recommendations for the diagnosis and management of X-linked hypophosphataemia

X-linked hypophosphataemia (XLH) is the most common cause of inherited phosphate wasting and is associated with severe complications such as rickets, lower limb deformities, pain, poor mineralization of the teeth and disproportionate short stature in children as well as hyperparathyroidism, osteomalacia, enthesopathies, osteoarthritis and pseudofractures in adults. The characteristics and severity of XLH vary between patients. Because of its rarity, the diagnosis and specific treatment of XLH are frequently delayed, which has a detrimental effect on patient outcomes. In this Evidence-Based Guideline, we recommend that the diagnosis of XLH is based on signs of rickets and/or osteomalacia in association with hypophosphataemia and renal phosphate wasting in the absence of vitamin D or calcium deficiency. Whenever possible, the diagnosis should be confirmed by molecular genetic analysis or measurement of levels of fibroblast growth factor 23 (FGF23) before treatment. Owing to the multisystemic nature of the disease, patients should be seen regularly by multidisciplinary teams organized by a metabolic bone disease expert. In this article, we summarize the current evidence and provide recommendations on features of the disease, including new treatment modalities, to improve knowledge and provide guidance for diagnosis and multidisciplinary care.

Hemiepiphysiodesis using tension band plates: does the initial screw angle influence the rate of correction?

PURPOSE

When using tension band plates for angular deformity correction, the literature is unclear regarding the most effective screw insertion angle to use. This study evaluates the correlation between initial screw angle and the average rate of correction during hemiepiphysiodesis using tension band plates.

METHODS

This retrospective study includes 35 patients (47 physes) with genu valgum deformity (17 idiopathic and 18 fibular hemimelia) who underwent insertion of Eight-Plates between 2010 and 2015. Initial screw angle was determined from the intraoperative fluoroscopic images. Radiographs were obtained within three months of surgery, and follow-up films were obtained every three to six months. Change in mechanical lateral distal femoral angle, medial proximal tibial angle and screw angle was obtained from each follow-up radiograph. Initial screw angle was correlated with the average rate of correction during the entire treatment period. The average rate of angular correction during first and last follow-up periods was also compared.

RESULTS

The relationship between the initial screw angle and the mean rate of angular correction was not statistically significant (p = 0.2). The rate of angular correction during the first follow-up period (mean of 4.7 months) was 0.86° per month compared with 0.71° per month during the last follow-up period (mean of 5.1 months).

CONCLUSION

Application of a tension band plate with a divergence angle ranging from 0° to 30° results in similar rates of angular correction. For surgeons inserting screw-plate tension band devices, there does not seem to be any necessity to make the screws parallel or divergent. We recommend that screw placement be anatomically correct, i.e. not impinging on the physis, rather than favouring any particular divergence angle.

LEVEL OF EVIDENCE

IV.

How Accurate is the Multiplier Method in Predicting the Timing of Angular Correction After Hemiepiphysiodesis?

PURPOSE

The purpose of the study was to validate the accuracy of the Multiplier Method (MM) in predicting the timing of angular correction after hemiepiphysiodesis and to determine the role of using skeletal age when calculating those predictions.

METHODS

This retrospective study included 131 physes in 77 patients treated with hemiepiphysiodesis to gradually correct a coronal plane deformity before skeletal maturity. To compare the MM's predictions to the actual treatment duration, the "desired angular correction" was considered the actual achieved angular correction determined from the "endpoint x-ray" (last x-ray before implant removal). We measured the bone length and width of the growth plate from the preoperative x-ray and calculated the MM's prediction of the duration of treatment based on the MM formula. We compared the predicted duration to the observed duration of treatment for each case. The difference was calculated by subtracting the observed duration from the predicted duration. The result was the "absolute difference," which is the number of months over or under predicted by the MM.

RESULTS

The mean absolute difference between the MM's predicted duration and the observed duration was 2.31 months, which was highly significant (P≤0.001). The MM's prediction agreed with the observed duration of treatment (ie, zero absolute difference) in 15% of the predictions, 69% were under predicted, and 16% were over predicted. Sixty-eight percent of the absolute differences were within 3 months regardless of the direction of error. The mean difference was relatively less in genu varum cases and was statistically significant (P=0.047). Comparing the mean difference using chronological age and skeletal age in the formula showed no statistically significant difference.

CONCLUSIONS

The MM has a tendency to under predict. Therefore, doing a guided growth right before skeletal maturity should be started 2 to 4 months earlier than suggested by the MM. Moreover, our data did not show that the bone age gave more accurate predictions than chronological age.

LEVEL OF EVIDENCE

Level IV.

Achondroplasia: a comprehensive clinical review

Achondroplasia is the most common of the skeletal dysplasias that result in marked short stature (dwarfism). Although its clinical and radiologic phenotype has been described for more than 50 years, there is still a great deal to be learned about the medical issues that arise secondary to this diagnosis, the manner in which these are best diagnosed and addressed, and whether preventive strategies can ameliorate the problems that can compromise the health and well being of affected individuals. This review provides both an updated discussion of the care needs of those with achondroplasia and an exploration of the limits of evidence that is available regarding care recommendations, controversies that are currently present, and the many areas of ignorance that remain.

A constellation of orthopaedic deformities in connection with cartilage oligomeric matrix protein mutation

BACKGROUND

Trendelenburg's gait can be observed in Legg-Calvé-Perthes disease, antalgic gait observed in osteoarthropathy and waddling gait is usually seen in genu varum and circumduction gait in patients with genu valgum. Disabling pain was a prime manifestation in slipped capital femoral epiphysis (SCFE). Limited joint range of motion with an inability to bear full weight on an affected extremity with swaying and wide-based gait is seen in patients with malalignment of the lower limbs. All the above-mentioned deformities have been labelled as idiopathic. The main objective of this article is to approach to the aetiology understanding.

PATIENTS AND METHODS

Ten children (3 girls and 7 boys with age average of 9 years) presented with variable deformities; Perthes-like deformity, genu varum/valgum and osteoarthropathy and one patient with SCFE. Clinical and radiological phenotypes were the baseline tool of diagnosis. Genotypic characterisations were performed.

RESULTS

Diverse clinical presentations of Perthes-like disease, osteoarthropathy, genu varum/valgum and SCFE were the most prominent skeletal abnormalities in patients manifested cartilage oligomeric matrix protein (COMP) gene mutation.

CONCLUSION

: The value of presenting this article is fourfold; first to signify that mutation study was essential for the increment of knowledge related to the genotype-phenotype relationships. Second, to indicate that professional awareness is needed to differentiate between the hidden pathologies in patients with Perthes-like deformity, genu varum, genu valgum and early osteoarthritis in correlation with COMP gene mutation. Third, it is mandatory to question the validity of the term idiopathic. Fourth, this article is an attempt to sensitise orthopaedic physicians and surgeons that deformities might be stemmed from diverse forms of intrinsic bone disorders.

Eight-plate epiphysiodesis

Aims

Guided growth using eight-plates is commonly used for correction of angular limb deformities in growing children. The principle is of tethering at the physeal periphery while enabling growth in the rest of the physis. The method is also applied for epiphysiodesis to correct limb-length discrepancy (LLD). Concerns have been raised regarding the potential of this method to create an epiphyseal deformity. However, this has not been investigated. The purpose of this study was to detect and quantify the occurrence of deformities in the proximal tibial epiphysis following treatment with eight-plates.

Patients and Methods

A retrospective study was performed including 42 children at a mean age of 10.8 years (3.7 to 15.7) undergoing eight-plate insertion in the proximal tibia for correction of coronal plane deformities or LLD between 2007 and 2015. A total of 64 plates were inserted; 48 plates (34 patients) were inserted to correct angular deformities and 16 plates (8 patients) for LLD. Medical records, Picture Archive and Communication System images, and conventional radiographs were reviewed. Measurements included interscrew angle, lateral and medial plateau slope angles measured between the plateau surface and the line between the ends of the physis, and tibial plateau roof angle defined as 180° minus the sum of both plateau angles. Measurements were compared between radiographs performed adjacent to surgery and those at latest follow-up, and between operated and non-operated plateaus. Statistical analysis was performed using BMDP Statistical Software.

Results

Slope angle increased in 31 (49.2%) of operated epiphyses by a mean of 5° (1° to 23°) compared with 29 (31.9%) in non-operated epiphyses (p = 0.043). Roof angle decreased in 29 (46.0%) of operated tibias and in 25 (27.5%) of non-operated ones by a mean of 5° (1° to 18°) (p = 0.028). Slope angle change frequency was similar in patients with LLD, varus and valgus correction (p = 0.37) but roof angle changes were slightly more frequent in LLD (p = 0.059) and correlated with the change in inter screw angles (r = 0.74, p = 0.001).

Conclusion

The use of eight-plates in the proximal tibia for deformity correction and limb-length equalization causes a change in the bony morphology of the tibial plateau in a significant number of patients and the effect is more pronounced in the correction of LLD. Cite this article: Bone Joint J 2018;100-B:1112–16.

Schmid's Type of Metaphyseal Chondrodysplasia: Diagnosis and Management

OBJECTIVES

There are several types of metaphyseal chondrodysplasia and various clinical types have been differentiated. The Schmid type of metaphyseal chondrodysplasia is the most common. Diffuse metaphyseal flaring, irregularity, and growth plate widening, which are most severe in the knees, are the most striking radiological features of this disease. The Schmid type of metaphyseal dysostosis is characterized by failure of normal mineralization of the zone of provisional calcification, leading to widened physes and enlarged knobby metaphyses, effectively causing shortening of the tubular bones, splaying of the metaphyses, coxa vara, and bow legs. Orthopaedic interventions were primarily performed on the lower extremities.

METHODS

Twelve children (seven girls and five boys) aged 7-10 years were enrolled in this study. Moderate short stature was a uniform feature associated with predominant involvement of the proximal femora and bow legs resulted in the development of angular deformities. A waddling gait was a consequence of coxa vara in eight children. Valgus osteotomy of the proximal femur was planned after physeal closure for the group of children with coxa vara. Hemiepiphysiodesis was performed to re-align the genu varum in three children.

RESULTS

Other forms of metaphyseal dysostosis were ruled based on full clinical and radiographic phenotypes, with confirmation through molecular pathology. Mutations in the COL10A1 gene located on chromosome 6q21-q22.3 were confirmed. Re-alignment was accomplished in our group of patients.

CONCLUSION

The most striking clinical features of Schmid metaphyseal chondrodysplasia which appear within the first 2-3 years of life are: moderate short limbs and short stature, a waddling gait, and increasing shortness of stature with age. The Schmid type of metaphyseal chondrodysplasia is a disorder that arises from defective type X collagen, which is typically found in the hypertrophic zone of the physes. Moderate short stature and a waddling gait associated with pain are the most common clinical presentations. Osteotomies to correct bow legs are sometimes combined with lengthening procedures. Recurrence of the deformities with growth is not uncommon; therefore, hemiepiphysiodesis or stapling might be indicated in some cases.

Management of growth arrest: Current practice and future directions

INTRODUCTION

Premature growth arrest can pose a challenge to the orthopedic surgeon. Various options for treating physeal arrest exist.

METHODS

Systematic searches were conducted on PubMed/Medline, ScienceDirect, OVID, and Cochrane Library. Secondary searching was performed, where certain articles from reference lists of the selected studies were reviewed that were not found in the primary search.

RESULTS

This review article discusses the different methods of management for premature growth arrest.

CONCLUSIONS

The use of mesenchymal stem cells provides a promising alternative treatment modality.

Growth modulation by hemi epiphysiodesis using eight-plate in Genu valgum in Paediatric population

INTRODUCTION

Genu valgum is an angular deformity of the knee, often treated surgically by osteotomy or by growth modulation (using tension band, staples, transphyseal screws and eight-plate which require removal after correction). With this study, we attempt to evaluate the efficacy, rate of correction and complications with the use of 8-plate in the correction of genu valgum deformity in children.

MATERIAL AND METHOD

In a retrospective study of 24 patients with 11 bilateral and 13 unilateral (35 knees) genu valgum deformity which required surgical corrections were included. There were 11 males, and 13 females and all of them were treated with Steven's technique (Stevens, 2006) using eight-plate and monitored closely.

RESULT

Twenty-four patients with an average age of 10 years and 8 months (range: 5 yrs, 7 months-14 yrs, 2 months), with the mean preoperative & post-implant removal (Post-IR) tibiofemoral angle of 22.02° ± 5.15° (range 14°-31°) & 6.14° ± 1.92° (range 2°-10°) respectively, required an average time period of 1yr & 5m ± 5 m (range 10 months-28 months) for correction after which implants were removed. Of the 35 limbs, we achieved excellent results in 91.6%. One case (4.16%) had a partial correction of the deformity, and one case (4.16%) had reported with a superficial infection which was taken care. There were 2 cases (8.33%) of over-correction, which was gradually self-corrected during follow-up.

CONCLUSION

Our results reflect the efficacy of flexible titanium eight plate which corrects angular deformity by acting as a tension band on one side of the growth plate and offers the advantage of reversible Hemi epiphyseal growth modulation. Guided growth modulation is a best available alternative for the treatment of an angular deformity in the patients with open physis.

Comparing Percutaneous Physeal Epiphysiodesis and Eight-Plate Epiphysiodesis for the Treatment of Limb Length Discrepancy

BACKGROUND

Either percutaneous or eight-plate epiphysiodesis have been shown to be effective growth modulation techniques for the treatment of limb length discrepancies (LLD). However, few studies compared the outcomes of both techniques with some confounding results. The aim of this study was to evaluate the outcomes of the both techniques in the treatment of the LLD.

METHODS

Between 2004 and 2012, medical records of all cases that underwent either eight-plate or percutaneous epiphysiodesis (PE) were reviewed. Age at surgery, sex, diagnosis, surgical site (proximal tibia/distal femur), time of follow-up, complications, and additional procedures were noted. Correction of the LLD was evaluated to calculate the rate of correction and the percentage of improvement from the long-leg standing x-rays or scanograms, collected at each visit.

RESULTS

There were 24 patients in the eight-plate (10 girls and 14 boys) and 48 patients in the PE group (28 girls and 20 boys). No statistically significant difference was found in the age, sex, preoperative LLD, or follow-up between groups. Both groups reached to an average LLD below 2 cm. The percentage of improvement was significantly higher in the PE group (P=0.031). The rate of individual femoral and tibial correction did not differ between the groups.

CONCLUSIONS

Both methods are shown to be effective for LLD correction. However, PE led to greater improvement during the same follow-up time with fewer complications and less need for additional surgical procedures.

Treatment of genu valgum in children by means of temporary hemiepiphysiodesis using eight-plates: short-term findings

Background

Idiopathic genu valgum is a frequently diagnosed growth disorder in adolescence. Whenever the possibilities of conservative therapy have been exhausted, leg straightening by means of hemiepiphysiodesis has become the standard form of treatment. Because of their flexible screw-plate connection, eight-Plates have been reported in the literature to lead to lower complications regarding implant loosening and fracture compared to other implants.

The aim of this retrospective survey was to analyse our own patient population who were treated for genu valgum by means of temporary hemiepiphysiodesis near the knee using eight-Plates to modulate growth.

Methods

Between July 2007 and July 2015, 198 eight-Plates were implanted near the knee in 132 children suffering from genu valgum to modulate growth. Depending on the deformity analysis, an eight-Plate was implanted on the distal medial femur and/or the proximal medial tibia. By December 2015, they had been removed from 105 patients. The etiology of genu valgum was mainly idiopathic or associated withobesity. Evaluation was carried out clinically and radiologically (whole-leg X-ray in standing) including determination of the joint angles.

Results

The median follow-up period was about 46 months (12–102 months). The median age at implantation was 12.7 +/−6.76 years. Of the 105 patients, 45.7% (n = 48) were girls. The eight-Plates remained in place for a median period of 13 +/−1.76 months. Irrespective of the location of hemiepiphysiodesis, the intermalleolar distance was corrected to a median of 0 +/−2.1 cm while the anatomical femorotibial angle was corrected by on average 9 +/−2.7 °Mechanical lateral distal femoral angle changed an average 7 +/− 7.72 degrees. Medial proximal tibial angle changed an average 4 +/− 6.02 degrees. Complications necessitating surgery occurred in 2.8% of cases (1 wound infection, 3 corrective osteotomies following overcorrection).

Conclusion

Temporary hemiepiphysiodesis using eight-Plates is a gentle, simple and effective procedure used to treat genu valgum by modulating growth. Slight overcorrection is desirable due to the rebound phenomenon, especially in young patients with high growth potential and risk groups such as obese children. In adolescents with only low growth potential (older than 14 years), owing to the low correction potential, the indication should be strictly reviewed and the possible failure of therapy should be discussed with the patient. No differences were observed regarding the location of the implanted eight-Plates (femoral or tibial).

The orthopaedic management of lower limb deformity in hypophosphataemic rickets

BACKGROUND

Many patients with X-linked hypophosphataemic rickets (X-LHPR) demonstrate significant lower limb deformity despite optimal medical management. This study evaluates the use of guided growth by means of hemi-epiphysiodesis to address coronal plane deformity in the skeletally immature child.

METHODS

Since 2005, 24 patients with X-LHPR have been referred to our orthopaedic unit for evaluation. All patients had standardised long leg radiographs that were analysed sequentially before and after surgery if any was performed. The rate of correction of deformity was calculated based on peri-articular angles and diaphyseal deformity angles measured at regular intervals using Traumacad software. Clinical records were reviewed to obtain relevant clinical and demographic details. Statistical analysis was performed using SPSS 23 (SPSS Inc., Chicago, IL, USA).

RESULTS

The indication for surgical intervention was a mechanical axis progressing through Zone 2 or in Zone 3 despite one year of optimised medical treatment. The 15 patients underwent 16 episodes of guided growth (30 limbs, 38 segments) at a mean age of 10.3 years. In four limbs, surgery has only taken place recently; and in three limbs, correction is ongoing. Neutral mechanical axis was restored in 16/23 (70%) limbs: six improved and one limb (one segment) required osteotomy for residual deformity. The mean rate of angular correction per month was 0.3° for the proximal tibia and 0.7° for the distal femur. Patients with ≥ 3 years of growth remaining responded significantly better than older patients (p = 0.004). Guided growth was more successful in correcting valgus than varus deformity (p = 0.007). In younger patients, diaphyseal deformity corrected at a rate of 0.2° and 0.6° per month for the tibia and the femur, respectively. There has been one case of recurrent deformity. Patients with corrected coronal plane alignment did not complain of significant residual torsional malalignment. Serum phosphate and alkaline phosphatase levels did not affect response to surgery.

CONCLUSIONS

Guided growth is a successful, minimally invasive method of addressing coronal plane deformity in X-LHPR. If coronal plane deformity is corrected early in patients with good metabolic control, osteotomy can be avoided.

Multiplier method may be unreliable to predict the timing of temporary hemiepiphysiodesis for coronal angular deformity

Background and purposes

The multiplier method was introduced by Paley to calculate the timing for temporary hemiepiphysiodesis. However, this method has not been verified in terms of clinical outcome measure. We aimed to (1) predict the rate of angular correction per year (ACPY) at the various corresponding ages by means of multiplier method and verify the reliability based on the data from the published studies and (2) screen out risk factors for deviation of prediction.

Methods

A comprehensive search was performed in the following electronic databases: Cochrane, PubMed, and EMBASE™. A total of 22 studies met the inclusion criteria. If the actual value of ACPY from the collected date was located out of the range of the predicted value based on the multiplier method, it was considered as the deviation of prediction (DOP). The associations of patient characteristics with DOP were assessed with the use of univariate logistic regression.

Results

Only one article was evaluated as moderate evidence; the remaining articles were evaluated as poor quality. The rate of DOP was 31.82%. In the detailed individual data of included studies, the rate of DOP was 55.44%.

Conclusion

The multiplier method is not reliable in predicting the timing for temporary hemiepiphysiodesis, even though it is prone to be more reliable for the younger patients with idiopathic genu coronal deformity.

Guided growth for valgus deformity correction of knees in a girl with osteopetrosis: a case report

Autosomal dominant osteopetrosis (Albers-Schönberg disease) classically displays the radiographic signs of osteosclerosis. The main ADO complications involve the skeleton: low-impact bone fractures, scoliosis and hip osteoarthritis. Management of osteopetrosis-related orthopedic problems is a surgical challenge due to increased bone density. The healing process is very slow in these patients because of bone remodeling defects related to osteoblast function failure. In case of bone deformities, a realignment method should be appropriated to osteopetrosis conditions. This article presents a case report of operative treatment of an 11-year-old girl affected with ADO, who underwent a simultaneous valgus knee deformity correction of both limbs with medial eight-plate epiphysiodesis. Simultaneous correction of valgus deformity on both limbs using an extraperiosteal tension plate technique for medial tibial hemiepiphysiodesis was performed in a girl of 11.5 years old with autosomal dominant osteopetrosis. The treatment duration from surgery to complete deformity correction and removal of plates was 18 months. The final aMPTA was 86° on the right side and 85° on the left side. The correction rate was 0.61°/month (right tibia) and 0.67°/month (left tibia). The MAD correction rate was evaluated as 1.5 mm/month for the right limb and 1.6 mm/month for the left limb. At the moment of plate removal, one screw was broken because of tight fixation in osteopetrotic bone. But it did not compromise the final result. The latest follow-up visit at the age of 14 years 6 months revealed excellent realignment without any deformity relapse. There was no any functional impairment. We consider the guided growth by tension band technique as very interesting and promising solution for treatment of pediatric angular deformity in patients with OP. This method allows to avoid osteotomy and related important risk of delayed union or nonunion frequently observed in osteopetrosis.

Level of evidence: Level IV.

Correction of lower limb deformities in children with renal osteodystrophy by guided growth technique

PURPOSE

Renal osteodystrophy (ROD) may cause severe lower limb deformities in children. The purpose of this study is to evaluate the efficacy of the temporary hemiepiphysiodesis for the correction of lower limb deformities in children with ROD.

METHODS

Guided growth correction by hemiepiphysiodesis has been performed in skeletally immature patients with deformities of the lower limbs caused by ROD. The correction of the mechanical axes of the lower limbs and its correction speed have been evaluated.

RESULTS

A total of seven patients with ROD, five males and two females, were treated with the above technique. The average age of the patients at their first surgery was 7.8 years (2.9 to 13.6). The average follow-up time 5.2 years (2.3 to 8). There were 13 valgus deformities and one varus deformity of the knee. The measure of the lower limb angular deformity was in the range of 10° to 47°. Restoration of normal mechanical axis was achieved in all patients at the final follow-up. Three patients relapsed and required further hemiepiphysiodesis. The average time for correction was 20 months (7 to 30). The average speed of correction was 0.49° per month for a tibia and 1.73° per month for a femur. There were two minor complications: a screw mobilisation and a screw breakage occurred during removal.

CONCLUSION

Guided growth technique by hemiepiphysiodesis is a mini-invasive surgical procedure that has been found to be effective for the correction of misalignment due to ROD in skeletally immature patients. The method has allowed progressive correction of the deformities at any age in childhood. These patients are predisposed to relapse to their deformities, thus a strict follow-up is required.

Comparative study between staples and eight plate in the management of coronal plane deformities of the knee in skeletally immature children

PURPOSE

To compare two commonly used methods of temporary hemiepiphysiodesis (staples and figure of eight plate) in the management of coronal plane deformities of the knee in skeletally immature children.

METHODS

This prospective study was conducted between November 2012 and November 2015. A total of 40 patients with 67 affected knee joints, having at least 1 year of skeletal growth remaining, were included in the study. Angular correction was measured by recording the mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), and anatomical tibio-femoral angle (TFA) (for the overall alignment of lower limbs). Implant removal was done after 5° of overcorrection was achieved. The rate of correction (° per month) and complications related to each technique were recorded.

RESULTS

The most common diagnosis was idiopathic genu valgum. The overall rate of correction (TFA) was 1.2° for staples and 1.4° for eight plate (p = 0.70, not statistically significant). The correction in mLDFA was statistically better in the eight plate group, whereas an opposite trend was recorded in mMPTA. Implant-related complications were present in two cases of the staples group.

CONCLUSION

Although the overall correction rate was similar in both groups, implant-related complications were lower with figure of eight plate. In idiopathic genu valgum (the most common diagnosis), the correction was statistically better in the eight plate group. We recommend figure of eight plate over staples in managing these deformities.

Limits of Growth Modulation Using Tension Band Plates in the Lower Extremities

Growth modulation using tension band plates (TBP) has been shown to be a safe, effective, and popular method for correcting pediatric frontal plane angular deformity around the knee. Recently, TBPs have been used to achieve reversible epiphysiodesis to treat limb-length discrepancy. Many surgeons have expanded the indications to include diagnoses other than frontal plane angular deformities, anatomic sites other than the knee, and correction of sagittal and oblique plane deformities. Despite the rapid acceptance of TBPs, the limits of this option have not been explored. We undertook a systematic literature review and found that the success rate for idiopathic cases approaches 100% with a low complication rate. Pathologic cases have a slightly lower success rate and a higher complication rate. The potential to avoid osteotomy with growth modulation makes TBPs a reasonable option for all but the most extreme pediatric frontal and sagittal plane lower extremity deformities. Applications to hip deformities remain unproven.

Growth Retardation (Hemiepiphyseal Stapling) and Growth Acceleration (Periosteal Resection) as a Method to Improve Guided Growth in a Lamb Model

BACKGROUND

Guided growth corrects pediatric limb deformity by inhibiting growth on the convexity of the bone. Both modular and rigid implants have been used; we endeavor to determine whether a clear advantage of one implant exists. We further hypothesize that improved correction could be realized by accelerating growth with resection of the periosteum.

METHODS

Sixteen lambs underwent guided growth of the medial proximal tibia (the opposite limb served as a control). Group 1 used a rigid staple (n=5); group 2 a modular plate and screw construct (n=5), and group 3 had a similar device plus periosteal resection (n=6). Radiographs tracked the progression of deformity in the coronal plane. Before sacrifice, pulsed fluorochrome labels allowed for temporal and spatial growth rate analysis. At sacrifice, True Deformity was calculated (and compared with control tibia) from standardized radiographs in the coronal and sagittal planes. Device Efficiencies were normalized by dividing True Deformity produced (degrees) by the Expected Growth gain (mm) from the control limb.

RESULTS

Group 3 produced greater coronal plane deformity than group 1 by an average of 2.2 degrees per month (P=0.001) and group 2 by an average of 2.4 degrees per month (P=0.0007). At sacrifice, groups 1 and 2 were equally effective at limiting growth to 75% of control; no differences in growth retardation were noted. No differences in Device Efficiency were noted between groups 1 and 2. The Device Efficiency was significantly different between groups 1 and 2 with comparison with group 3 (P=0.05 and P=0.022); with a 2.5 degree/mm faster deformation in the stripped cohort.

CONCLUSIONS

Rigid implants initially produced deformity quicker than modular constructs; yet ultimately, both implants were equally effective at guiding growth. Device Efficiency for the modular group improved significantly with the addition of periosteal stripping as method to accelerate growth.

Hemiepiphysiodesis Implants for Late-onset Tibia Vara: A Comparison of Cost, Surgical Success, and Implant Failure

BACKGROUND

The purpose of this study was to compare hemiepiphysiodesis implants for late-onset tibia vara and to evaluate patient characteristics that may predict surgical failure.

METHODS

This is a retrospective review of late-onset tibia vara patients treated with temporary hemiepiphysiodesis from 1998 to 2012. Mechanical axis deviation (MAD), mechanical axis angle, mechanical lateral distal femoral angle, and medial proximal tibial angle were measured on standing bone length radiographs. Surgical failure was defined as residual deformity requiring osteotomy, revision surgery, or MAD exceeding 40 mm at the time of final follow-up. Implant failure was recorded. Costs included implants and disposables required for construct placement. Staple constructs included 2 or 3 staples. Plate constructs included the plate, screws, guide wires, and drill bits.

RESULTS

A total of 25 patients with 38 temporary lateral proximal tibia hemiepiphysiodeses met the inclusion criteria. The average body mass index (BMI) was 39.1 kg/m with an average follow-up of 3.0 years (minimum 1 y). Surgical failure occurred in 57.9% of patients. Greater BMI (P=0.05) and more severe deformity (MAD, mechanical axis angle, and medial proximal tibial angle; P<0.01) predicted higher rates of surgical failure. Younger age predicted higher rates of implant failure (P<0.01). There were no differences in surgical or implant failure between staple and plate systems. Hospital costs of plate constructs ($781 to $1244) were 1.5 to 3.5 times greater than the staple constructs ($332 to $498).

CONCLUSIONS

Greater BMI, more severe deformity, and younger age were predictive of surgical or implant failure. There was no difference in success between implant types, whereas the cost of plate constructs was 1.5 to 3.5 times greater than staples. The rate of surgical failure was high (58%) and consideration should be given to reserving hemiepiphysiodesis for patients with lower BMI and less severe deformity. In our population, if hemiepiphysiodesis was not offered to patients with BMI>35 or MAD>80 mm varus, the surgical failure rate would diminish to 28%. The failure rate outside these parameters would be 88%.

LEVEL OF EVIDENCE

Level II—Prognostic.

Does physical therapy prevent post-operative delay in return of function following tension-band plating?

PURPOSE

The clinical outcomes and complications of tension-band plating have been well documented, and commonly include a post-operative delay in return of function. We performed a retrospective comparison study to evaluate the capacity of immediate post-operative physical therapy to prevent this post-operative delay in return of function.

METHODS

Sixty-seven consecutive growth-deformity patients who were treated with tension-band plating at a single institution fulfilled the study criteria. Patients were allocated into two treatment groups: no post-operative physical therapy and immediately post-operative physical therapy. All patients were evaluated for delayed return of function, which was defined as use of crutches, lack of >90° flexion and full extension of the knee, or persistent pain requiring medication at the initial 2-week follow-up visit. Rates of delayed function were compared between the two treatment groups.

RESULTS

Among the study participants, 48 patients had no physical therapy and 19 patients had immediate post-operative physical therapy. Eighteen patients in the no physical therapy group reported a delay (37.5 %) while only 2 patients in the physical therapy treatment group reported a delay (10.5 %); p = 0.0386.

CONCLUSIONS

Delayed return of function dramatically affects pediatric patients, causing unnecessary absence from school and strain on the caregiver. Therefore, it is important to identify treatment modalities to help mitigate the complications of surgery. We conclude that the use of immediate post-operative physical therapy statistically significantly helps patients to return more rapidly to their functional level.

Caput valgum associated with developmental dysplasia of the hip: management by transphyseal screw fixation

PURPOSE

A late finding of some hips treated for developmental dysplasia of the hip (DDH) is a growth disturbance of the lateral proximal femoral physis, which results in caput valgum and possibly osteoarthritis. Current treatment options include complete epiphysiodesis of the proximal femoral physis or a corrective proximal femoral osteotomy. Alternatively, a transphyseal screw through the inferomedial proximal femoral physis that preserves superolateral growth might improve this deformity.

METHODS

This study evaluates the effect of such a transphyseal screw on both femoral and acetabular development in patients with caput valgum following open treatment of DDH. These patients were followed clinically and radiographically until skeletal maturity. Preoperative and postoperative radiographs were assessed, measuring the proximal femoral physeal orientation (PFPO), the head-shaft angle (HSA), Sharp's angle and the center edge angle of Wiberg (CE angle).

RESULTS

Thirteen hips of 11 consecutive patients were followed prospectively. The age at the time of transphyseal screw placement was between 5 and 14 years. The mean improvement of the PFPO and HSA was 14° (p < 0.01) and 11° (p < 0.001), respectively. The mean improvement of Sharp's angle and CE angle was 4.7° (p < 0.01) and 5.8° (p < 0.02), respectively. Five patients underwent screw revision.

CONCLUSIONS

A transphyseal screw across the proximal femoral physis improved the proximal femur and acetabular geometry.