Guided growth for tibia vara (Blount's disease)

The Effect of Guided Growth Surgery on Langenskiold Stage and Mechanical Axis in Early-Onset Blount Disease: A Retrospective Case Series

INTRODUCTION

Our understanding of the efficacy of guided growth surgery with tension-band plating (TBP) in early-onset Blount disease is evolving. Preliminary work has demonstrated that TBP can normalize the mechanical axis, yet its effect on Langenskiöld stage (LS) has not previously been reported. The primary outcome of this study was improvement in LS after TBP. Secondary outcomes were improvement in LS at most recent follow-up and improvement in mechanical axis deviation (MAD), mechanical medial proximal tibial angle, and mechanical lateral distal femoral angle at treatment completion and most recent follow-up.

METHODS

A retrospective review was done of patients with early-onset Blount disease treated with TBP between January 1, 2010, and December 31, 2019, across two institutions. Inclusion criteria were a radiographic diagnosis of early-onset Blount disease (LS changes present), surgery with TBP, and follow-up beyond implant removal. Radiographs before surgery, at removal of hardware (ROH), and at most recent follow-up were evaluated.

RESULTS

Twenty-five limbs in 16 children who underwent TBP at a mean age of 5.8 ± 2.3 years were included. Implants were in situ a mean of 1.9 ± 0.7 years. The mean follow-up after ROH was 3.6 ± 1.4 years. LS ranged from 1 to 5 preoperatively with 14 of 25 limbs (56%) staged ≥3. LS improved in 15 of 25 limbs (60%) at ROH and in 21 of 25 limbs (84%) at most recent follow-up. Langenskiöld changes resolved in 7 of 25 limbs (28%) at most recent follow-up. Preoperatively, the MAD was varus in all limbs, but at ROH, the MAD had improved in 22 of 23 limbs with neutral or valgus alignment in 20 of 23 limbs (87%). At most recent follow-up, 16 of 23 limbs (70%) maintained improved alignment.

DISCUSSION

There was improvement/resolution of LS and varus deformity in early-onset Blount disease in most patients who underwent TBP. Based on these results, TBP for early-onset Blount disease should be the first-line surgical treatment.

LEVEL OF EVIDENCE

IV.

Current advancements in therapeutic approaches in orthopedic surgery: a review of recent trends

Recent advancements in orthopedic surgery have greatly improved the management of musculoskeletal disorders and injuries. This review discusses the latest therapeutic approaches that have emerged in orthopedics. We examine the use of regenerative medicine, including stem cell therapy and platelet-rich plasma (PRP) injections, to accelerate healing and promote tissue regeneration. Additionally, we explore the application of robotic-assisted surgery, which provides greater precision and accuracy during surgical procedures. We also delve into the emergence of personalized medicine, which tailors treatments to individual patients based on their unique genetic and environmental factors. Furthermore, we discuss telemedicine and remote patient monitoring as methods for improving patient outcomes and reducing healthcare costs. Finally, we examine the growing interest in using artificial intelligence and machine learning in orthopedics, particularly in diagnosis and treatment planning. Overall, these advancements in therapeutic approaches have significantly improved patient outcomes, reduced recovery times, and enhanced the overall quality of care in orthopedic surgery.

Physeal Migration During Knee-guided Growth With Tension Band Plates: Influence of Implant Position

OBJECTIVE

Physeal migration during guided growth with tension band plates (TBPs) has been poorly described. The positioning factors associated with this phenomenon and its clinical implications are unknown. Our aim is to determine the influence of implant position on the risk of physeal migration during knee-guided growth with TBP.

METHODS

Retrospective study of 491 patients who underwent temporary hemi or epiphysiodesis with TBP around the knee between 2007 and 2019. We identified 29 patients who presented physeal migration during follow-up. Demographic and clinical data were collected, and the following measures were obtained from the immediate postoperative radiographs: epiphyseal screw base-physis distance/epiphyseal screw tip-physis distance, interscrew angle, epiphyseal screw-physis angle(ES-PHa)/metaphyseal screw-physis angle, plate-physis angle, epiphyseal screw-plate angle/metaphyseal screw-plate angle, and epiphyseal screw-physis length ratio. Using follow-up radiographs, the type of physeal migration of the epiphyseal screw (touch, occupy, or traverse) and the status of the physis after implant removal (unaltered, physeal bar, and skeletal maturity) were also recorded. A descriptive analysis of the cases and a case-control comparison of imaging studies were performed.

RESULTS

The median patient age at intervention was 12.2 years (interquartile range: 11.3 to 14.1), and 76% were males. A statistically significant difference between cases and controls was obtained for epiphyseal screw base-physis distance (3.7 vs 6.3; P = 0.029), epiphyseal screw tip-physis distance (3.6 vs 7.85; P = 0.002), ES-PHa (-0.1 vs 7.45; P = 0.007), and plate-physis angle (85.45 vs 88.60; P = 0.012). In a categorical analysis, a significant difference was found for the ES-PHa categories ( P = 0.002) and for the ES-PHa/metaphyseal screw-physis angle categorical pair ( P = 0.018). In 16, 17, and 12 cases the physis was touched, occupied, or traversed, respectively, although we found no physeal alterations after plate removal.

CONCLUSIONS

In our study, physeal migration of TBP is not an uncommon phenomenon, although no physeal abnormalities were detected. Convergent placement of the epiphyseal screw with the base or tip close to the physis should be avoided as this position is associated with a higher risk of physeal migration.

LEVEL OF EVIDENCE

Level III-case-control study.

Recurrence and Complication Rates of Surgical Treatment for Blount's Disease in Children: A Systematic Review and Meta-Analysis

BACKGROUND

Blount's disease is a growth disorder of the proximal tibia that causes progressive genu varum in children. Surgical treatment is recommended if the deformity worsens, but which intervention is best remains controversial. This study aims to identify factors influencing outcomes and determine the most effective surgical approach.

METHODS

A systematic review was conducted of studies published before January 2022.

RESULTS

In total, 63 retrospective studies with CEBM IIIb/IV levels were included (1672 knees in 1234 patients). The most commonly reported treatment was acute correction via osteotomy (47%), followed by hemiepiphysiodesis (22%) and gradual correction (18%). Combined procedures were reported in 13% of cases. The overall recurrence rate was 18%, with a significant difference when comparing the recurrence rates after gradual correction with those after hemiepiphysiodesis (7% and 29%, respectively). Major complications beyond recurrence were observed in 5% of cases. A meta-analysis of the available raw data showed a significantly increased recurrence rate (39%) among treated children who were between 4.5 and 11.25 years of age and were followed for a minimum follow-up of 2.5 years.

CONCLUSIONS

Overall, poor evidence with which to establish an optimal treatment for Blount's disease was found. This study remarked on the need for early diagnosis, classification, and treatment of infantile tibia vara, since a significant rate of recurrence was found in neglected cases.

Predisposing factors for migration of epiphyseal screws into physis in tension band plating

The migration of epiphyseal screws into growing physis in tension band plating is a known complication. We investigated the screw migration into physis in 10 patients (18 plates) to study the various technical details, which may have contributed to this complication. The methodology involved retrospective review of radiological records. Among these 10 affected patients, in four patients, there were eight additional tension band plates, which had remained uncomplicated ('controls') at the time when implant failure was detected. We statistically compared the length of epiphyseal screw, proximity of screw start point to the physis, screw trajectory angle, interscrew angle and correction rate between the migrated and other uncomplicated plates. Majority patients were postrachitic ( n = 7). The mean time from primary procedure to detection of radiological complication was 15.1 months. The mean epiphyseal screw length proportion in migrated and uncomplicated plates matched. The starting point of epiphyseal screw was relatively closer to physis in migrated plates. The trajectory of epiphyseal screw with respect to physis was more divergent in the migrated plates ( P = 0.02). All implants were inserted in a divergent manner with mean interscrew angle being 22.3° for migrated and 13.8° for the uncomplicated plates ( P = 0.02). The correction rate of the implant reduced as it failed. Osteopenic bone and pathological physis predispose to migrated plates. Technically, a wider trajectory of epiphyseal screw and too divergent screws should be avoided. A migrated implant becomes less effective in its function.

Coronal plane deformity around the knee in the skeletally immature population: A review of principles of evaluation and treatment

Coronal plane deformity around the knee, also known as genu varum or genu valgum, is a common finding in clinical practice for pediatricians and orthopedists. These deformities can be physiological or pathological. If untreated, pathological deformities can lead to abnormal joint loading and a consequent risk of premature osteoarthritis. The aim of this review is to provide a framework for the diagnosis and management of genu varum and genu valgum in skeletally immature patients.

Guided Growth Procedures: Broken Tension Band Implants in Patients With Blount Disease

BACKGROUND

Tension band plate and screw implants (TBI) are frequently used for temporary hemiepiphyseodeses to manage angular deformity in growing children. The reported implant breakage rate, when TBI is used for deformities in patients with Blount disease, is much higher than when used in other diagnoses. Our hypothesis is that perioperative factors can identify risks for TBI breakage.

METHODS

A retrospective case-control study was performed of 246 TBI procedures in 113 patients with Blount disease at 8 tertiary pediatric orthopaedic centers from 2008 to 2018. Patient demographics, age at diagnosis, weight, body mass index (BMI), radiographic deformity severity measures, location, and types of implants were studied. The outcome of implant breakage was compared with these perioperative factors using univariate logistic regression with Bonferroni correction for multiplicity to significance tests.

RESULTS

There were 30 broken implants (12%), failing at mean 1.6 years following implantation. Most failures involved the metaphyseal screws. Increased BMI was associated with increased implant breakage. Increased varus deformity was directly associated with greater implant breakage and may be a more important factor in failure for those below 7 years compared with those 8 years or above at diagnosis. There was a 50% breakage rate for TBI with solid 3.5 mm screws in Blount disease with onset 8 years or above of age. No demographic or implant factors were found to be significant.

CONCLUSIONS

Breakage of TBI was associated with increased BMI and varus deformity in patients with Blount disease. Larger studies are required to determine the relative contribution and limits of each parameter. Solid 3.5 mm screws should be used with caution in TBI for late-onset Blount disease.

LEVEL OF EVIDENCE

Level III.

Guided growth using a tension-band plate in Blount's disease

Our observational study's objective was to determine how effective guided growth with tension-band plates was to correct the deformity in Blount's disease. We reviewed the records of 14 children (18 limbs) with Blount's disease who were treated with tension-band plates as the only surgical intervention at a single institution over eight years. Five children (seven limbs) had infantile Blount's disease with Langenskiöld stage ≤2. Nine children (11 limbs) had late-onset Blount's disease. The mean age at operation was 7.2 years (SD, 3.1, range, 2.9-11.8). The tension-band plate effectively corrected the varus deformity in 78% (14/18) of limbs. Correction to normal mechanical alignment was achieved in 67% (n = 12) of limbs at a mean of 18 months (SD, 7, range, 9-31). Failure to achieve correction of the mechanical axis was due to delayed implant removal and overcorrection in 11% (2/18), mechanical failure due to screw fixation failure in 11% (2/18) and in 6% (1/18) due to a misplaced epiphyseal screw. There was a greater magnitude of correction in the Infantile Blount's disease group (mean, 26°, SD, 9°) when compared to the children with late-onset Blount's disease (13°, SD, 4°) (P = 0.021). The mean correction rate was 1.8°/month in the Infantile Blount's disease group and 0.7°/month in the late-onset Blount's disease group, respectively (P = 0.014). Our findings support the use of tension-band plating in Blount's disease. Further research is required to determine the ideal indications and to investigate the long-term outcome of guided growth in Blount's disease. Level of evidence: Level 4.

Percutaneous hemiepiphysiodesis using transphyseal screws for adolescent tibia vara

Hemiepiphysiodesis around the knee is becoming the mainstay procedure in adolescents for a wide range of aetiological deformities, when considering adolescent tibia vara (ATV), the published series have variable results. The purpose of this study was to review our experience with the percutaneous transphyseal screw (PETS) in these patients followed until bone maturity. We analysed the charts from 13 patients (20 knees) that underwent lateral tibial hemiepiphysiodesis using PETS. The radiographs were accessed before surgery, at implant removal, when occurred, and at the final follow-up. The clinical evaluation noted if there were complaints regarding pain or range of motion, and the radiographic assessment included: the femorotibial angle, the mechanical axis zone, the anatomic lateral distal femoral angle, and medial mechanical proximal tibial angle. There was one overcorrection, and after the screw removal (14 knees), rebound was observed in two knees modifying the result from excellent to good in all three knees. No bone bars and no implant breakage were observed. At the last appointment, all patients had normal knee range of motion, and two patients had unilateral alignment complaints, one of whom referred to occasional pain. Overall, the surgery was excellent in 12 knees (60%), good in six knees (30%), and poor in two knees (10%). This technique is indicated to be well tolerated and effective for treating ATV. When a complete correction cannot be obtained, in our opinion, it is advantageous to at least stabilise the deformity and postpone osteotomies until after skeletal maturity. Level of Evidence: Level IV - Case Series, Therapeutic Study.

Guided Growth for Tibial Recurvatum

Aim and objective

Sagittal guided growth of the distal anterior femur has been shown to be effective for the correction of fixed knee flexion deformity that is encountered in clinical practice. The opposite deformity, namely genu recurvatum, is comparatively uncommon in children. The most common aetiology is post-traumatic. Acute correction by means of osteotomy has significant associated risks. Our objective was to determine whether a posterior 8-plate would suffice in correcting tibial recurvatum and obviate the need for an osteotomy.

Materials and methods

We included a total of five deformities, three boys (one bilateral) and one girl, managed by means of tethering of the posterior proximal tibial physis with a tension band plate. Standard radiographs obtained preoperatively and at follow-up included a standing anteroposterior (AP) of the legs noting limb lengths and the mechanical axis. We also obtained standing lateral views of each knee in maximal extension to measure and compare the posterior proximal tibial angle (PPTA).

Results

The same-day surgery was well tolerated and there were no surgical or post-operative complications. The preoperative PPTA ranged from 106° to 117° and averaged 84° at follow-up. Correction occurred in an average of 20 months (range of 18–24 months). The patient with bilateral recurvatum due to Hurler's syndrome developed unilateral recurrent recurvatum culminating in percutaneous reinsertion of the metaphyseal screw. For each patient, knee hyperextension and associated pseudo-laxity resolved and limb lengths remained equal at follow-up.

Conclusion

Children with progressive genu recurvatum typically present with an insidious onset of symptoms. Guided growth of the posterior proximal tibia is a safe and effective means of correcting the deformity; osteotomy was avoided in this series.

Level of evidence

III – retrospective case series – no controls.

How to cite this article

Stevens P, Stephens A, Rothberg D. Guided Growth for Tibial Recurvatum. Strategies Trauma Limb Reconstr 2021;16(3):172–175.

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.

Deformity Reconstruction Surgery for Blount's Disease

Blount's disease is an idiopathic developmental abnormality affecting the medial proximal tibia physis resulting in a multi-planar deformity with pronounced tibia varus. A single cause is unknown, and it is currently thought to result from a multifactorial combination of hereditary, mechanical, and developmental factors. Relationships with vitamin D deficiency, early walking, and obesity have been documented. Regardless of the etiology, the clinical and radiographic findings are consistent within the two main groups. Early-onset Blount's disease is often bilateral and affects children in the first few years of life. Late-onset Blount's disease is often unilateral and can be sub-categorized as juvenile tibia vara (ages 4-10), and adolescent tibia vara (ages 11 and older). Early-onset Blount's disease progresses to more severe deformities, including depression of the medial tibial plateau. Additional deformities in both groups include proximal tibial procurvatum, internal tibial torsion, and limb length discrepancy. Compensatory deformities in the distal femur and distal tibia may occur. When non-operative treatment fails the deformities progress through skeletal maturity and can result in pain, gait abnormalities, premature medial compartment knee arthritis, and limb length discrepancy. Surgical options depend on the patient's age, weight, extent of physeal involvement, severity, and number of deformities. They include growth modulation procedures such as guided growth for gradual correction with hemi-epiphysiodesis and physeal closure to prevent recurrence and equalize limb lengths, physeal bar resection, physeal distraction, osteotomies with acute correction and stabilization, gradual correction with multi-planar dynamic external fixation, and various combinations of all modalities. The goals of surgery are to restore normal joint and limb alignment, equalize limb lengths at skeletal maturity, and prevent recurrence. The purpose of this literature review is to delineate basic concepts and reconstructive surgical treatment strategies for patients with Blount's disease.

Guided growth vs.Tibial osteotomy at early stage of Blount disease in squelletically immature patients

BACKGROUND

There are no comparative study between guided growth and tibial osteotomy in early stage of Blount disease (BD) to our knowledge. The aim of this work was to compare the results of patients treated by these two techniques.

METHOD

This was a retrospective, descriptive, and analytical study over a period of 5 years in including 17 children (24 Knees) with an early stage of infantile BD in two centers. Patient were classified in two groups: group 1(treated by guided growth), group 2 (treated by Tibial Osteotomy).Preoperative alignment analysis using the tibial femoral angle (HKA) and the proximal medial tibial mechanical angle (mMPTA) were compared with three measurements taken postoperatively in each of the groups. The mean variations of the angles were compared between the two groups.

RESULTS

Socio-demographic characteristics were similar for the two groups. Median age at surgery was 6.5 ± 2.5 [3-9 years] in group 1 and 6.8 ± 2.9 years [3-9 years]. At a follow-up of 24 ± 3.5 months, the limb alignment was significantly corrected (1,03°/month) in group 1 (median HKA 144°-171°; p = 0,001; median MMPTA 78°-87°, p = 0,018), and in group 2 we observed at a follow-up of 23 ± 15 months a progressive loss (0,52°/month) of the correction obtained immediately postoperatively (median HKA 160°-176°(immediate post operative) to 165,5°; p = 0,31; median MMPTA = 78°-86° (immediate post operative) to 80,5°; p = 0,37).There was a statistically significant difference between the mean variation in HKA between the two groups (group 1 = 22,5; group 2 = 4,5, p = 0.00), as well as for MMPTA; (group 1 = 7; group 2 = 2,5, p = 0,023).The rate of correction was 78% in group 1 with no rebound at a median follow-up after removal of the material of 10 ± 2.4 months. Within group 2, the rate of correction was 10% with a recurrence rate of 60%.

CONCLUSION

Guided growth appears to be the best treatment for early stage of BD in squelletically immature patients.

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.

Distal Femoral Physeal Bar Resection Combined With Guided Growth for the Treatment of Angular Limb Deformity Associated With Growth Arrest: A Preliminary Report

PURPOSE

Distal femoral growth arrest can result in progressive deformities and functional disability. The treatment is challenging given the significant growth potential of the distal femoral physis. This study addresses the short-term outcomes after distal femoral physeal bar resection combined with guided growth for the treatment of angular limb deformity.

METHODS

We conducted a retrospective analysis of patients treated with distal femoral physeal bar resection, fat graft interposition, and growth modulation with a tension-band plate. Data recorded included patient demographics, growth arrest cause, physeal bar size, time-to-surgery, details of the operative procedure, and complications. The mechanical axis zones, tibiofemoral angle, and the anatomic lateral distal femoral angle were assessed on 51-inch anteroposterior standing radiographs.

RESULTS

Five patients (3 male individuals) with valgus (n=4) and varus deformities (n=1) due to physeal arrests of the distal femur were analyzed. The cause of the physeal arrest was trauma (n=3) and infection (n=2). The average age at the time of surgery was 6.6 years (range: 2 to 11 y). Average size of the physeal bar was 413.4 mm, which represented 16.8% of the total distal femoral physis (range: 12% to 26%). Four of the 5 patients had a total correction of the deformity in 14.3 months (range: 9 to 22 mo). One patient required correction by osteotomy and external fixation. Postoperatively, 1 patient presented no improvement, and 4 had restoration of the longitudinal bone growth and alignment. Two patients had rebound valgus: one is being observed and another has undergone a repeat guided growth procedure.

CONCLUSIONS

Distal femoral physeal bar resection combined with tension-band hemiepiphysiodesis provides a viable option for the correction of angular deformities associated with physeal arrest. Longer follow-up is required to evaluate future growth of the distal femoral physis after this combined procedure.

LEVEL OF EVIDENCE

Level IV-therapeutic study.

Double Level Osteotomy Assisted by 3D Printing Technology in a Patient with Blount Disease: A Case Report

CASE

We describe the case of a 26-year-old patient diagnosed with Blount disease. She underwent a medial oblique supracondylar biplanar closing-wedge osteotomy of the distal femur followed by a medial oblique biplanar opening-wedge osteotomy of the proximal tibia. 3D printed cutting guides were used for the procedures. At 18 months after surgery, the patient is pain-free and walks without aids.

CONCLUSIONS

Using 3D printed guides allowed for accurate correction of the deformity and reduced the risk of damaging critical structures. These guides could be an appropriate alternative for the surgical treatment of patients with Blount disease.

Guided Growth with Hemiplateau Elevation as an Alternative to Epiphysiodesis for Treatment of a Young Patient with Advanced Infantile Blount Disease: A Case Report

CASE

Infantile Blount disease results from deceleration of growth by the proximal posteromedial tibial physis causing tibia vara. In advanced disease stages, surgical treatment is indicated. Owing to the young age and advanced Langenskiöld stage in this patient, a novel technique was performed combining lateral proximal physeal tethering with medial hemiplateau elevation osteotomy to correct the articular surface and unload the medial proximal tibial physis.

CONCLUSION

Together, these procedures allow for correction of alignment while preserving growth potential. This technique was successful in correcting tibia vara due to infantile Blount disease while allowing continued growth in a 5-year-old patient.

The efficacy of guided growth as an initial strategy for Blount disease treatment

PURPOSE

The aim of this study was to evaluate the success of guided growth by temporal hemiepiphysiodesis of the lateral proximal tibia as a first line treatment option for Blount disease.

METHODS

This was a retrospective multicentre study conducted in five centres, covering data on 55 limbs in 45 patients, with an average follow-up of 24.5 months following plate insertion. Preoperative alignment analysis was compared with three measurements taken postoperatively. The normalization of the mechanical medial proximal tibia angle (mMPTA) was defined as the primary outcome measure.

RESULTS

Mean age at surgery was 9.5 years. Average preoperative mMPTA was 77°. On average, at 24.5 months post-surgery, mMPTA was 86.33°, while 43/55 limbs (78.18%) have achieved normalization (mMPTA 85° to 90°). Average rate of correction was 1° per month. When grouping the children as infantile (11 limbs), juvenile (12 limbs) and adolescent (32 limbs), operated on before the age of four years, between four and ten years and after the age of ten years, respectively, 63.63%, 66.67%, 87.5% have completed correction of deformity during the follow-up period. Interestingly, the femoral component of the deformity has achieved correction as well in 33/55 limbs (64%).

CONCLUSION

Hemiepiphysiodesis is an effective first line treatment for Blount disease. Overall success rate is good but varies according to child's age. Adolescent Blount has the best chance of achieving full correction while same treatment is less effective in infantile Blount.Level of evidence: IV.

Tibia vara or Blount's disease: Why an early diagnosis and treatment are important?

Tibia vara is an asymmetrical disorder of the proximal tibia that produces a threedimensional deformity, which was first described by Blount in 1937. A 6-year-old boy presented with a history of anterior knee pain with progressive bowing of his right leg over the last 1 year after having a fall while playing soccer. An early diagnosis and treatment of this disease can have a great functional impact and lead to very good health outcomes.

Tension Band Plate (TBP)-guided Hemiepiphysiodesis in Blount Disease: 10-Year Single-center Experience With a Systematic Review of Literature

BACKGROUND

Primary treatment for Blount disease has changed in the last decade from osteotomies or staples to tension band plate (TBP)-guided hemiepiphysiodesis. However, implant-related issues have been frequently reported with Blount cases. The purpose of our study is to evaluate the surgical failure rates of TBP in Blount disease and characterize predictors for failure.

METHODS

We performed an Institutional Review Board-approved retrospective chart-review of pediatric patients with Blount disease to evaluate the results of TBP from 2008 to 2017 and a systematic literature review. Blount cases defined as pathologic tibia-vara with HKA (hip-knee-ankle) axis and MDA (metaphyseal-diaphyseal angle) deviations ≥11 degrees were included in the analysis. Surgical failure was categorized as mechanical and functional failure. We studied both patient and implant-related characteristics and compared our results with a systematic review.

RESULTS

In 61 limbs of 40 patients with mean follow-up of 38 months, we found 41% (25/61) overall surgical failure rate and 11% (7/61) mechanical failure rate corresponding to 11% to 100% (range) and 0% to 50% (range) in 8 other studies. Statistical comparison between our surgical failure and nonfailure groups showed significant differences in deformity (P=0.001), plate material (P=0.042), and obesity (P=0.044) in univariate analysis. The odds of surgical failure increased by 1.2 times with severe deformity and 5.9 times with titanium TBP in the multivariate analysis after individual risk-factor adjustment. All 7 mechanical failures involved breakage of cannulated screws on the metaphyseal side.

CONCLUSIONS

Most of the studies have reported high failure rates of TBP in Blount cases. Besides patient-related risk factors like obesity and deformity, titanium TBP seems to be an independent risk factor for failure. Solid screws were protective for mechanical failure, but not for functional failure. In conclusion, efficacy of TBP still needs to be proven in Blount disease and implant design may warrant reassessment.

LEVEL OF EVIDENCE

Level III-retrospective comparative study with a systematic review.

Guided growth for the Treatment of Infantile Blount's disease: Is it a viable option?

Introduction

Guided growth with temporary hemiepiphysiodesis has gained interest as a less invasive means for the treatment of coronal plane lower extremity deformities as well as leg length discrepancies. Its application to infantile Blount's disease has been less reported. The object of this study was to identify predictive factors of guided growth for treatment of infantile Blount's.

Methods

A retrospective review was performed of children undergoing guided growth for the treatment of infantile Blount's disease over an eight-year period. Inclusion criteria included treatment with THE for infantile Blount's disease. Clinical information, preoperative Langenskiold classification, and intra-operative and post-operative data. Preoperative variables were used to identify risk factors for speed of correction and the need for subsequent surgery.

Results

A total of 11 patients, 17 extremities, meeting inclusionary criteria. Preoperatively, 7 extremities were classified as Langenskiold stage ≥3, with 12 being classified as stage ≤2. Overall, the Drennan's angle improved from 18.3° to 0.3° by final follow-up at an average of 4.31 years. Eight extremities demonstrated deformity recurrence/persistence (stage ≤2:33% vs stage ≥3: 100%), requiring 24 reoperations. Children with Langenskiold stage ≥3 demonstrated a significantly higher rate of reoperation.

Conclusion

Guided growth is a viable treatment option for Infantile Blount's disease presenting with Langenskiold stage ≤2 disease at treatment initiation. The treatment course can expect a 33% rate of recurrent deformity, treated successfully with repeat THE. No child stage ≤2 required corrective osteotomy. Caution should be used when considering guided growth for children presenting with Langenskiold stage ≥3.

Growth Modulation for Knee Coronal Plane Deformities in Children With Nutritional Rickets: A Prospective Series With Treatment Algorithm

To report prospectively the radioclinical outcome of guided growth surgery for coronal plane deformities around the knee in young children with nutritional rickets on the intermediate term, to assess the responsiveness of torsional deformities of the tibias to guided growth regarding function and objective clinical parameters, and to propose a treatment algorithm.

Cozen's deformity: resolved by guided growth

Proximal tibial metaphyseal fractures in children can lead to progressive and symptomatic tibial valgus. Corrective osteotomy has been abandoned, due to frequent complications, including recurrent valgus deformity. While spontaneous remodelling has been reported, this is not predictable. For children with persistent deformities, we have resorted to guided growth of the tibia. We present 19 patients who were successfully treated with guided growth, tethering the proximal medial physis. There were ten boys and nine girls, ranging in age from two to 13.6 years at the time of intervention. The mean follow-up from injury was 7.3 years. We documented the intermalleolar distance, mechanical axis deviation (by zone), medial proximal tibial angle (MPTA), and leg length discrepancy. Removal of the plate, or more recently, the metaphyseal screw, was undertaken upon normalization of the mechanical axis. Including the four patients who have undergone repeat tethering for recurrent valgus (one patient-twice), we are effectively reviewing 24 Cozen's phenomena, making this the largest series reported in the literature. Correction of the mechanical axis and the proximal medial tibial angle was achieved in all but one patient. Limb length inequality at follow-up ranged from 0.1 to 1.5 cm, with a mean of 0.5 cm. There have been five recurrences in four patients to date; four corrected with repeat tethering and one is pending. Two patients developed significant over correction because of parental failure to pursue timely follow-up. Both have corrected to neutral with lateral tibial physeal tethering. Ten patients have attained skeletal maturity and required no further treatment. The remaining nine patients will be followed until maturity. Guided growth is an excellent choice for the management of post-traumatic tibial valgus. Our rationale for restricting medial overgrowth is twofold: (1) to restore the MPTA and (2) to reduce the length discrepancy due to tibial overgrowth caused by the fracture. Recognizing the potential for recurrent deformity following implant removal, our standard practice now includes removal of just the metaphyseal screw and subsequent reinsertion, in the event of rebound valgus deformity.Level of evidence Therapeutic IV, retrospective series/no control cohort.

Update on treatment of adolescent Blount disease

PURPOSE OF REVIEW

Treatments available to correct adolescent Blount disease deformities differ in terms of features, advantages, and disadvantages. Each is indicated, therefore, for different scenarios of severity, physeal condition, and maturity. The purpose of this review is to update basic concepts, surgical treatments, and controversies concerning this disorder.

RECENT FINDINGS

The cause of Blount disease is unknown although etiologic factors as morbid obesity and hypovitaminosis D are thought to be associated with it. Recently, semiinvasive techniques (guided growth) have been proposed for mild deformities but remain controversial. Osteotomies with external fixation (hexapodes) are still the most recommended corrective treatment in this condition.

SUMMARY

Little is known about the origin and natural history of Blount disease. Treatment is always surgical and, given their complexity, should be preceded by a thorough analysis and planning regarding all deformities. Treatment principles are to correct the three-dimensional deformity and avoid recurrence. The choice of technique mainly depends on patient maturity and severity. Guided growth is a good choice for more immature patients with moderate deformities. Progressive correction using osteotomy or physeal distraction is indicated for patients with severe deformities and low remaining growth. The Taylor spatial frame is currently the most popular progressive correction device.

Percutaneous Epiphysiodesis Using Transphyseal Screws: a Case Series Demonstrating High Efficacy

BACKGROUND

Percutaneous epiphysiodesis using transphyseal screws (PETS) has been associated with implant failure, implant prominence, angular deformities, and delayed growth inhibition.

QUESTIONS/PURPOSES

The aim of this study was to assess the complication rate and efficacy (defined as actual growth inhibition divided by expected growth inhibition) of PETS and to identify factors associated with improved efficacy.

METHODS

Patients who underwent distal femoral and/or proximal tibial PETS between January 2007 and June 2014 were identified. Complications, efficacy, and final limb-length discrepancy (LLD) were calculated using multipliers and inhibition rates based on previous growth. Associations between efficacy and screw insertion angle (SIA), body mass index, and number of threads crossing the physis were calculated.

RESULTS

Eight-two patients (126 treated physes) were included. The mean pre-operative LLD was 27.7 mm (SD = 7.5). Following epiphysiodesis, 15 had temporary pain (18%), five had temporary effusion (6.1%), four had broken implants (4.9%), four developed mild angulation (4.9%), and three had failed epiphysiodesis requiring revision (3.7%). Thirty-one underwent screw removal (n = 31, 38%). Mean LLD at maturity was 17.3 mm (SD = 5.8 mm). Mean efficacy at the distal femur was 97% (SD = 46%), at the proximal tibia was 108% (SD = 66%) and was 103% (SD = 57%) overall. Increased screw threads across the lateral proximal tibial physis (Spearman's correlation coefficient = 0.67; 95% CI = 0.40-0.94) and higher BMI (Spearman's correlation coefficient = 0.55; 95% CI = 0.34-0.77) were positively associated with increased efficacy.

CONCLUSIONS

The efficacy of PETS may be more favorable than previously reported. Only 3.7% had serious complications requiring revision epiphysiodesis, lower than previous reports. Attention to sufficient screw threads across the physis may be important in optimizing PETS results.