Anterior Hemiepiphysiodesis of the Distal Tibia: A Step-by-step Surgical Technique Guide

Aim

This paper aims to serve as a guide for surgeons to prepare, execute, and perfect anterior hemiepiphysiodesis of the distal tibia (AHDT).

Background

Treatment of persistent or recurrent equinus deformity following multiple conservative and surgical interventions in patients with idiopathic clubfoot or neuromuscular conditions can be challenging, and multiple surgical options are presented in the existing literature. Anterior hemiepiphysiodesis of the distal tibia is an option that seems to be safe and efficient in treating this entity. To the best of our knowledge, there is not yet any detailed description of this surgical technique in the English literature.

Technique

The AHDT detailed surgical technique includes patient positioning, careful distal anterior tibial approach, placement of guided growth plates, fixation with epiphyseal and metaphyseal screws under fluoroscopic guidance, meticulous closure, and postoperative measures.

Conclusion

This guide can be used pre-operatively to plan the surgery, intra-operatively to aid in smooth and safe step progression, and post-operatively to assist in critical critiquing.

Clinical significance

By understanding the various stages of the surgery as well as the anatomy, pitfalls can be avoided and AHDT can be performed efficiently.

How to cite this article

Katz A, Dumas É, Hamdy R. Anterior Hemiepiphysiodesis of the Distal Tibia: A Step-by-step Surgical Technique Guide. Strategies Trauma Limb Reconstr 2023;18(3):174-180.

Anterior Distal Tibial Guided Growth for recurrent equinus deformity in idiopathic Congenital Talipes Equinovarus treated with the Ponseti method

INTRODUCTION

Distal Anterior Tibial Guided Growth has been shown to be useful to correct recurrent equinus deformity after open surgical release for Congenital Talipes Equinovarus. This has not been evaluated in a recurrence after use of the Ponseti method, where soft tissue releases are currently understood as the mainstay of treatment.

METHODS

Patients with recurrence of equinus component of CTEV, who underwent DATGG with at least 6-month follow-up were identified retrospectively. The criteria for performing this procedure were (1) equinus not correctable to neutral passively (2) the feeling of a bony block to dorsiflexion clinically as evidenced by a supple Achilles' tendon at maximum dorsiflexion and (3)a finding of a flat-top talus radiologically. Successful treatment was defined by the achievement of heel strike on observation of gait. Details of the index procedure including concurrent procedures, any complications and their treatment, past and subsequent treatment episodes were retrieved from electronic patient records. Pre-op and last available post-op X-rays were evaluated for change in the anterior distal tibial angle and for flat-top talus deformity.

RESULTS

We identified 22 feet in 16 patients, with an average follow-up was 25 (8.8-47.3) months. The mean aDTA changed from 88.9 (82.3-94.5) to 77.0 (65.0-83.9) degrees, which was statistically significant (p < 0.0001) using the Paired t-test. Clinically, 17 feet (77 %) obtained a plantigrade foot with a normal heel strike. Complications were identified in 5 feet and include staple migration, oversized staple, superficial infection, iatrogenic varus deformity. Recurrence after completed treatment was noted in one foot.

CONCLUSION

This procedure should form a part of the armamentarium of procedures for treating equinus component of CTEV recurrences even in feet not treated previously by open procedures. When used in patients without significant surgical scarring it helps to address bony and soft-tissue factors, leading to effective treatment.

LEVEL OF EVIDENCE

Therapeutic Level IV.

Indications and timing in isolated medial femoral hemiepiphysiodesis for idiopathic genu valgum: A systematic review

INTRODUCTION

Temporary isolated medial femoral hemiepiphysiodesis (TIMFH) represents a safe and effective technique widely used to treat idiopathic genu valgum. Recent studies mainly concentrated on comparing outcomes of different implants, while less attention has been reserved to the proper indications and timing for surgery. The aim of this systematic review was to provide evidence-based guidelines about indications for device implant and removal and postoperative management.

METHODS

A comprehensive literature search was performed across three databases to select articles concerning TIMFH in the treatment of idiopathic genu valgum. Studies involving other etiologies or concomitant surgical procedures were excluded. Quality assessment of the included studies was conducted through the Newcastle-Ottawa Scale.

RESULTS

Ten studies involving 237 patients for a total of 446 knees were included in the analysis. Mean age at surgery was 11,4 years. Patients were considered for surgery using various clinical and radiological parameters. Intermalleolar distance (IMD) and mechanical lateral distal femoral angle (mLDFA) were the most common evaluated. Mean treatment time was 12 months. Rebound of the deformity occurred in 6,7% of cases.

CONCLUSION

Results of this review showed good consensus among authors. Patients undergoing TIMFH for IGV should be minimum 8 years old, with an IMD greater than 8 cm and a mLDFA lower than 87°. Postoperative management should comprise of quarterly clinic evaluations, and follow-up should last until skeletal maturity. The application of more uniform parameters in clinical practice may improve the establishment of the optimal timing for implant removal.

Natural behaviours after guided growth for idiopathic genu valgum correction: comparison between percutaneous transphyseal screw and tension-band plate

BACKGROUND

Percutaneous epiphysiodesis using a transphyseal screw (PETS) or tension-band plating (TBP) has shown favourable correction results; however, the physeal behaviours in terms of rebound, stable correction, or overcorrection after guided growth have not been completely understood. In patients with idiopathic genu valgum, we therefore asked: (1) How is the correction maintained after implant removal of guided growth? (2) Is there any difference in the natural behaviours after PETS or TBP removal at the femur and tibia?

METHODS

We retrospectively reviewed 73 skeletally immature limbs with idiopathic genu valgum treated with PETS or TBP. PETS was performed in 23 distal femurs and 13 proximal tibias, and TBP was performed in 27 distal femurs and ten proximal tibias. Mechanical axis deviation (MAD), mechanical lateral distal femoral angle (mLDFA), and mechanical medial proximal tibial angle were measured at pre-correction, implant removal, and final follow-up. Changes of ≤ 3° in mechanical angles after implant removal were considered stable. Comparisons between the implant, anatomical site, and existence of rebound were performed.

RESULTS

The mean MAD improved from - 18.8 mm to 11.3 mm at implant removal and decreased to -0.2 mm at the final follow-up. At the final follow-up, 39 limbs (53.4%) remained stable and only 12 (16.4%) were overcorrected. However, 22 limbs (30.1%) showed rebound. TBP was more common, and the correction period was longer in the rebound group (p < 0.001 and 0.013, respectively). In femurs treated with PETS, the mean mLDFA increased from 86.9° at implant removal to 88.4° at the final follow-up (p = 0.031), demonstrating overcorrection. However, a significant rebound from 89.7° to 87.1° was noted at the femur in the TBP group (p < 0.001). The correction of the proximal tibia did not change after implant removal.

CONCLUSION

The rebound was more common than overcorrection after guided growth; however, approximately half the cases demonstrated stable correction. The overcorrection occurred after PETS in the distal femur, while cases with TBP had a higher probability of rebound. The proximal tibia was stable after implant removal. The subsequent physeal behaviours after each implant removal should be considered in the guided growth.

Mechanics of guided growth of the distal femur for correction of fixed knee flexion deformities: an extra-articular technique

INTRODUCTION

Anterior distal femoral hemiepiphysiodesis using intra-articular plates for correction of pediatric fixed knee flexion deformities (FKFD) has two documented complications: postoperative knee pain and implant loosening. The aim of this study is to investigate the mechanical properties of a novel extra-articular technique for anterior distal femoral hemiepiphysiodesis in patients with FKFD and to compare them to the conventional technique.

MATERIALS AND METHODS

Sixteen femoral sawbones were osteotomized at the level of the distal femoral physis and fixed by rail frames to allow linear distraction simulating longitudinal growth. Each sawbone was tested twice: first using the conventional technique with eight plates placed anteriorly just medial and lateral to the femoral sulcus (group A) and then with plates inserted in the proposed novel location at the most anterior part of the medial and lateral surfaces of the femoral condyles with screws in the coronal plane (group B). Gradual linear distraction was performed, and the resulting angular correction was measured. Strain gauges were attached to the plates, and the amount of strain (and equivalent stress) over the plates in response to linear distraction was recorded. The two groups were compared using the Wilcoxon signed-rank test.

RESULTS

The amount of angular correction was statistically higher in group B (extra-articular plates) at 5, 10-, and 15-mm of distraction (p < 0.001). As regards stress over the plates, the maximum stress and the area under the curve (sum of all stresses measured throughout the distraction process) were significantly higher when the plates were inserted at the conventional position (group A) (p < 0.001).

CONCLUSIONS

During anterior distal femoral hemiepiphysiodesis, the fixation of the eight plates in the coronal plane at the anterior part of the femoral condyles may produce a greater amount of correction and a lower degree of stress over the implants as compared to the conventional technique.

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.

The effectiveness of adding guided growth to soft tissue release in treating spastic hip displacement

BACKGROUND

Guided growth at the proximal femur using one transphyseal screw corrects coxa valga and improves hip displacement in cerebral palsy. This study aimed to validate the effects of adding guided growth (GG) to soft tissue release (STR), in terms of decreasing the migration percentage (MP), compared to those with soft tissue alone.

METHODS

This retrospective study comprised patients with cerebral palsy who underwent soft tissue release alone (Group STR) or soft tissue release plus guided growth (Group GG) for hip displacement (mean age, 8.1 years; mean follow-up, 4.9 years). Difference in the MP and rate of controlling MP <40% at 2 years postoperatively and rate of revision surgeries at 5 years postoperatively were compared between the groups.

RESULTS

The two groups were comparable in age, side, and gross motor function level, but Group GG (n = 24) had more severe hip displacement preoperatively than did Group STR (n = 64). Group GG had a significantly greater 2-year decrease in the MP (-14.8% vs. -11.8%, p < 0.05) than did Group STR. Among patients with a pre-operative MP >50%, the rate of MP <40% was greater in Group GG (73%) than in Group STR (41%). Revision surgeries, mainly repeated guided growth and soft tissue release, were comparable between the groups.

CONCLUSIONS

This is the first comparative study to support adding guided growth to soft tissue release, as it results in greater improvements in hip displacement than that with soft tissue release alone. Non-ambulatory patients or severe hip displacement with MP 50%-70% could benefit from this less aggressive surgery by controlling the MP under 40% without femoral osteotomy.

Design of a New "U"-shaped Staple and Its Clinical Application in Postoperative Ankle Valgus of Congenital Pseudarthrosis of the Tibia in Children

Objective

There has been a lack of suitable epiphysis blocking materials due to the characteristics of less tissue coverage and narrow epiphysis in children's distal tibial medial malleolus. Therefore, this study is to investigate the clinical efficacy and safety of a new “U”‐shaped staple in the treatment of postoperative ankle valgus of congenital pseudarthrosis of the tibia (CPT).

Method

According to the inclusion and exclusion criteria, 33 patients with postoperative ankle valgus of CPT were treated with new “U”‐shaped staples from May 2013 to September 2019. The deformity of ankle valgus was gradually corrected by implanting a new “U”‐shaped staple on the medial side of the distal tibia. Clinical indexes such as the operation time, intraoperative bleeding and hospital stay were observed. Tibiotalar angle was selected as the evaluation index of ankle valgus. American Orthopedic Foot & Ankle Society (AOFAS) scale was used for clinical evaluation of ankle function. The tibiotalar angle, deformity correction rate and complications were evaluated by preoperative, postoperative and last follow‐up imaging data. Student's t‐test was used for statistical analysis.

Results

Thirty‐three patients, including 12 males and 21 females were included. All the patients were followed up for at least 14 months, with an average of 35 months. The average operation time was 23 (15–40) min, the average amount of intraoperative bleeding was 7.5 (4–10) mL, and the average hospital stay was 4.2 (3–6) days. The intraoperative tibiotalar angles of all patients were 74.2° ± 4.6°, the tibiotalar angle were 86.8° ± 4.9° when internal fixation was removed, and the tibiotalar angles at the last follow‐up were 84.3° ± 5.9°. The average orthopedic rate was 0.68° per month. No patients suffered from serious complications such as screw prolapse, osteomyelitis, wound infection, etc. Postoperative wound pain complications occurred in two patients, which were relieved after conservative treatment. The AOFAS score improved from 46.2 ± 9.4 before the operation to 74.6 ± 5.7 at the last follow‐up (P < 0.01). The ankle movement was good without joint stiffness. There was no epiphyseal plate injury after the removal of internal fixation.

Conclusion

The new “U”‐shaped staple is characterized by simple implantation, low notch, lower risk of fixation failure and close fitting with cortical bone. It is a safe and effective internal fixation system for the treatment of ankle valgus in children.

Guided growth versus varus osteotomy for type II avascular necrosis following surgery for developmental dysplasia of the hip

AIMS

The aim of this study was to compare outcomes of guided growth and varus osteotomy in treating Kalamchi type II avascular necrosis (AVN) after open reduction and Pemberton acetabuloplasty for developmental dysplasia of the hip (DDH).

METHODS

This retrospective study reviewed patients undergoing guided growth or varus osteotomy for Kalamchi type II AVN between September 2009 and January 2019. All children who had undergone open reduction and Pemberton acetabuloplasty for DDH with a minimum two-year follow-up were enrolled in the study. Demographic and radiological data, which included the head-shaft angle (HSA), neck-shaft angle (NSA), articulotrochanteric distance (ATD), Sharp angle (SA), and lateral centre-edge angle (LCEA) at baseline, two years, and at the extended follow-up, were compared. Revision rates were evaluated. Clinical outcomes using the Harris Hip Score were assessed two years postoperatively.

RESULTS

A total of 24 patients underwent guided growth and 19 underwent varus osteotomy, over a mean period of 3.3 years (95% confidence interval (CI) 2.8 to 3.8) and 5.2 years (95% CI 4.5 to 6.0), respectively. There were no differences in demographic and preoperative radiological data, except for a younger age at time of acetabuloplasty and larger ATD for the osteotomy group. The HSA did not differ at two years and the extended follow-up because of postoperative rebound in the osteotomy group. The NSA of the osteotomy group remained smaller postoperatively. There were no significant differences in the follow-up ATD, SA, and LCEA, except for a smaller two-year ATD of the osteotomy group. Seven patients (29.2%) in the guided growth group underwent revision surgery and none in the osteotomy group. The Harris Hip Score was similar between groups.

CONCLUSION

Guided growth and varus osteotomy had comparable results in improving caput valgum deformity, given the rebound of lateral tilting of the physis after osteotomy correction. There were no differences in clinical outcomes at two years postoperatively. Cite this article: Bone Joint J 2022;104-B(7):902-908.

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.

[Epiphysiodesis and hemiepiphysiodesis : Physeal arrest and guided growth for the lower extremity]

The principals of growth arrest by epiphysiodesis and growth guidance by hemiepiphysiodesis are effective and powerful surgical techniques in pediatric orthopedics. These procedures can be used to correct leg length discrepancies as well as sagittal, coronal and oblique deformities. A differentiation is made between temporary and permanent techniques. The most significant advantage is that these techniques are minimally invasive and have low complication rates compared to acute osteotomy and gradual deformity correction. For optimal outcome an exact preoperative planning is needed to ensure accurate timing of the procedure, especially when permanent epiphysiodesis techniques are used. Although epiphysiodesis and hemiepiphysiodesis around the pediatric knee are most frequently used and can be considered the gold standard treatment of coronal plane deformities and leg length discrepancies, novel techniques for the hip and ankle are increasingly being performed. The successful clinical results with low complications support the broad use of hemiepiphysiodesis and epiphysiodesis for a variety of indications in the growing skeleton with deformities and leg length differences.

Rebound predictors of varus-valgus deformities around the knee corrected by guided growth

PURPOSE

Coronal plane deformities around the knee are rather common condition in children. Guided growth by temporary hemiepiphysiodesis is considered to be the preferred primary treatment in many cases. Despite the popularity of hemiepiphysiodesis, the incidence of recurrence of deformity and predictors for rebound are not well defined. The objectives of this study were to determine the incidence of the recurrence of varus-valgus deformities around the knee treated by temporary hemiepiphysiodesis and possible predictors for the rebound.

METHODS

We retrospectively reviewed medical records and x-ray images of 130 patients with varus-valgus deformities around the knee treated by tension-band (eight-plate) hemiepiphysiodesis, between the years 2006 and 2016 in our institution. The incidence of rebound of varus-valgus deformities around the knee and possible predictors were analyzed.

RESULTS

Rebound of the deformity was observed in 10% of patients. Risk factors found to be in correlation with recurrence include young age, deformity of proximal tibia, proximal tibial medial growth plate beaking, and comorbidities (like metabolic disorders, multiple hereditary exostoses and genetic syndromes).

CONCLUSION

The results of this study show that there is a noteworthy incidence of rebound in patients treated by temporary hemiepiphysiodesis for coronal deformities around the knee. The risk factors are also outlined. These patients, especially the ones with risk factors, require close surveillance until maturity.

LEVEL OF EVIDENCE

Level III-Case control study.

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.

Guided growth in the correction of knee deformity in patients with congenital insensitivity to pain

Background

Orthopedic manifestations of congenital insensitivity to pain (CIP) can be devastating if left untreated. Knee deformities are common in patients with CIP and might lead to joint destruction and loss of walking ability. The purpose of the present study was to report the results and complications of guided growth procedures around the knee in patients with CIP.

Methods

In a retrospective review, all patients with CIP who underwent guided growth procedures around the knee from 2009 to 2017 at a tertiary referral hospital were evaluated. Patients with secondary insensitivity to pain (e.g., syringomyelia), as well as patients with incomplete records, were excluded. Demographic data, clinical findings, correction rate, and complications were recorded.

Results

Ten knees in six patients fulfilled the inclusion criteria. The median age was 10 (range, 5–12), with a mean follow-up of 31 months (range, 16–56). Distal femoral tension-band hemiepiphysiodesis was the most common procedure, followed by proximal tibial hemiepiphysiodesis. The mean correction rate was 0.28°/month for femoral deformity. Staples were removed prematurely in one patient due to extrusion. No cases of infection or skin dehiscence were observed. None of the patients needed a reconstructive knee procedure during the study period.

Conclusions

The findings of this study suggest that guided growth procedures might have a role in the correction of knee deformities in patients with CIP. However, the correction rate is lower than that of typically developing children, patients should be closely followed to prevent complications, and stringent patient selection criteria should be followed to ensure success.

Partial hardware removal in guided growth surgery: A convenient strategy?

BACKGROUND

Tension band plates (TPBs) are frequently used in guided growth (CG) surgeries. Recently, the concept of removing the metaphyseal screw only to stop the growth modulating effect rather than completely removing the implant, has gained popularity. Although this strategy would have certain potential advantages, the associated risks are unknown. The aim of this study is to report the experience of three institutions with this strategy.

METHODS

A database was compiled with the demographic information of patients treated by guided growth using TBPs between January 2014 and January 2019 at three institutions. The cases where only the metaphyseal screw was removed were identified. The records were reviewed to analyze the indications, demographic data, characteristics of the procedure, complications and need for additional procedures.

RESULTS

We reviewed 28 partial hardware removals, performed in 10 patients (all male). Initial surgery was indicated for angular deformity (N = 6), and leg-length discrepancy (N = 4). The average age at the time of surgery was 9.5 ± 2.9 years (range 4 to 13 years). Three procedures were performed on the distal femur, 3 on the proximal tibia, 2 on the distal tibia, and 20 combined. The average follow-up was 23.3 ± 11 months (range 12 to 52 months). We observed recurrence of deformities in 7 of 28 (22%) limbs that required re-insertion of the metaphyseal screw. Two patients presented complications from the procedure: soft tissue irritation (N = 1) and angular deformity (N = 1). Both patients required unplanned surgery.

DISCUSSION

Partial hardware removal in guided growth surgery could favor the presentation of complications. The benefits of this strategy must be considered against the possible undesired effects generated by its application.

STUDY DESIGN

Therapeutic study (Level IV).

A retrospective study of treatment of genu valgum/varum with guided growth: Risk factors for a lower rate of angular correction

The rate of angular correction (ROAC) is very unpredictable and may be affected by various factors in the treatment of genu valgum and varum by means of guided growth. The purpose of this study was to assess the ROAC in cases from our institution and to identify risk factors associated with the occurrence of lower ROAC.We retrospectively reviewed the chart records of 68 patients undergoing guided growth with figure-eight plate for the correction of genu valgum and varum. Based on the data from these patients, the annual increment of physeal growth was calculated and compared with data from the Anderson chart. The associations between patient characteristics and ROAC were evaluated with the use of univariate logistic regression.The mean rate of femoral angular correction was 10.29 degrees/year, while the mean rate of tibial angular correction was 7.92 degrees/year. In a univariate logistic regression analysis, the variables associated with a higher risk of lower ROAC included non-idiopathic coronal deformity of the knee (odds ratio = 13.58, p < 0.001) and body weight at or above the 95th percentile for children (odds ratio = 2.69, p = 0.020).Obesity and non-idiopathic coronal deformity of the knee are risk factors for lower ROAC. It is still uncertain whether severity of deformity, race, and operative procedure have a substantial effect on the rate of correction.Level III evidence.

Does screw position matter for guided growth in cerebral palsy hips?

AIMS

Guided growth has been used to treat coxa valga for cerebral palsy (CP) children. However, there has been no study on the optimal position of screw application. In this paper we have investigated the influence of screw position on the outcomes of guided growth.

METHODS

We retrospectively analyzed 61 hips in 32 CP children who underwent proximal femoral hemi epiphysiodesis between July 2012 and September 2017. The hips were divided into two groups according to the transphyseal position of the screw in the coronal plane: across medial quarter (Group 1) or middle quarter (Group 2) of the medial half of the physis. We compared pre- and postoperative radiographs in head-shaft angle (HSA), Reimer's migration percentage (MP), acetabular index (AI), and femoral anteversion angle (FAVA), as well as incidences of the physis growing-off the screw within two years. Linear and Cox regression analysis were conducted to identify factors related to HSA correction and risk of the physis growing-off the screw.

RESULTS

A total of 37 hips in Group 1 and 24 hips in Group 2 were compared. Group 1 showed a more substantial decrease in the HSA (p = 0.003) and the MP (p = 0.032). Both groups had significant and similar improvements in the AI (p = 0.809) and the FAVA (p = 0.304). Group 1 presented a higher incidence of the physis growing-off the screw (p = 0.038). Results of the regression analysis indicated that the eccentricity of screw position correlated with HSA correction and increases the risk of the physis growing-off the screw.

CONCLUSION

Guided growth is effective in improving coxa valga and excessive femoral anteversion in CP children. For younger children, despite compromised efficacy of varus correction, we recommend a more centered screw position, at least across the middle quarter of the medial physis, to avoid early revision. Cite this article: Bone Joint J 2020;102-B(9):1242-1247.

Usefulness of the Sauvegrain Method of Bone Age Assessment in Indian Children

INTRODUCTION

Bone age estimation is very useful in children undergoing epiphysiodesis or guided growth surgery especially during the years of accelerated growth. It may be noted that no data are available on bone age estimation for Indian children of this age group. Sauvegrain (French) method is a very useful and simple method for bone age assessment during the years of accelerated growth. We decided to check the usefulness and the accuracy of the Sauvegrain method in Indian children.

MATERIALS AND METHODS

A team of two pediatric orthopaedic surgeons and a radiologist scored elbow X-rays of 80 healthy children (40 boys and 40 girls), using the Sauvegrain method twice. Interobserver reliability and intraobserver reproducibility of the Sauvegrain scoring were assessed.

RESULTS

There was a very strong correlation between all observers in both rounds (r = > 0.8) and an excellent reproducibility by the same observer in both rounds (r = 0.955). Chronological and bone age are considered the same if the difference between them is less than 6 months. With this criterion bone and chronological ages matched in > 37% of boys and girls, similar to the study done in French children. In the nonmatching group, more children had delayed bone age compared to their chronological age.

CONCLUSION

The Sauvegrain method of bone age assessment described for French children was found to be useful in estimating bone age in Indian children. It is especially helpful in the clinical practice for detecting mismatch between the chronological and the radiological age before undertaking guided growth or epiphysiodesis.

Galvanotropic Chamber for Controlled Reorientation of Pollen Tube Growth and Simultaneous Confocal Imaging of Intracellular Dynamics

Successful fertilization and seed set require the pollen tube to grow through several tissues, to change its growth orientation by responding to directional cues, and to ultimately reach the embryo sac and deliver the paternal genetic material. The ability to respond to external directional cues is, therefore, a pivotal feature of pollen tube behavior. In order to study the regulatory mechanisms controlling and mediating pollen tube tropic growth, a robust and reproducible method for the induction of growth reorientation in vitro is required. Here we describe a galvanotropic chamber designed to expose growing pollen tubes to precisely calibrated directional cues triggering reorientation while simultaneously tracking subcellular processes using live cell imaging and confocal laser scanning microscopy.

Update on guided growth concepts around the knee in children

Guided growth is part of the surgical armamentarium for limb-length discrepancy or axial deformity. It is an old concept, with several apparently conflicting techniques that are in fact usually complementary. Depending on whether the aim is to slow or arrest growth, to treat length discrepancy or axial deviation, techniques differ and the choice is partly determined by the indication. It is thus essential to know the technical details for each: temporary or definitive, complete or asymmetric, with or without implant. Considerations of fashion and personal habits may outweigh basic principles, and it is important to go back to the princeps descriptions: the Phemister, Bowen, Blount, Métaizeau and Stevens techniques and others all have their surgical specificities Apart from surgery itself, he indication and choice of technique depend on the patient's age and whether the abnormality to be treated is isolated or part of a wider syndrome, all of this being included in a precise strategy based on planning calculations that are indispensable ahead of any surgery. Guided growth can also be implemented elsewhere than in the limbs: wrist, ankle, or even hip; and it is beginning to be possible to correct sagittal and rotational deformities. All of this is furthermore achievable using emerging techniques that are less invasive, are reversible, and show equal efficacy.

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.

MRI safety and imaging artifacts evaluated for a cannulated screw used for guided growth surgery

OBJECTIVE

Percutaneously-placed cannulated screws are the implant of choice for treatment of skeletal deformity associated with growing children that have spastic cerebral palsy (CP). These patients often require MRI examinations throughout their childhood to evaluate associated comorbidities and frequently for research protocols. There are concerns related to the use of MRI when metallic implants are present. Therefore, this study characterized MRI safety and imaging artifacts for a cannulated screw commonly used for guided growth.

METHODS

Standardized and well-accepted in vitro techniques were used to evaluate a cannulated screw (4.5 mm diameter x 50 mm length, 316 L stainless steel) for MRI issues. Static magnetic field interactions (i.e., translational attraction and torque) and artifacts were tested at 3-Tesla. Radiofrequency-related heating was assessed at 1.5-Tesla/64-MHz and 3-Tesla/128-MHz using relatively high levels of RF energy (whole-body averaged specific absorption rates of 2.7 W/kg and 2.9-W/kg, respectively). Artifacts were determined using T1-weighted, spin echo and gradient echo pulse sequences.

RESULTS

The cannulated screw exhibited minor magnetic field interactions (14° deflection angle, no torque). The highest temperature changes at 1.5-Tesla/64-MHz and 3-Tesla/128-MHz MRI were 2.1 °C and 2.4 °C, respectively. The maximum artifact size on a gradient echo sequence extended 20 mm relative to the dimensions of the implant.

CONCLUSIONS

The in vitro tests performed on the cannulated screw indicated that there were no substantial concerns with respect to the use of 1.5- and 3-Tesla MRI. Therefore, a patient with this cannulated screw can safely undergo MRI by following specific conditions to ensure safety.

Patellar Instability in the Skeletally Immature

PURPOSE OF REVIEW

This review will focus on the evaluation and management of patellar instability in the developing patient.

RECENT FINDINGS

A large number of surgical techniques have been described to prevent recurrent patellofemoral instability in the pediatric population, including both proximal and distal realignment procedures. The wide variety of treatment options highlights the lack of agreement as to the best surgical approach. However, when a comprehensive exam and workup are paired with a surgical plan to address each of the identified abnormalities, outcomes are predictably good. Patellar instability is a common knee disorder in the skeletally immature patient that presents a unique set of challenges. Rates of re-dislocation in pediatric and adolescent patients are higher than in their adult counterparts. Careful consideration of the physeal and apophyseal anatomy is essential in these patients. While the majority of primary patellar instability events can be treated conservatively, multiple events often require surgical intervention.

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.

Growth modulation for coronal deformity correction by using Eight Plates-Systematic review

Introduction

Coronal deformities are commonly encountered in paediatric orthopaedics and surgical treatment is indicated for severe deformities causing pain, function and cosmetic problems. In a growing bone, major surgical intervention like osteotomy with internal or external fixation can be avoided by growth modulation (hemiepiphysiodesis) using 8-plates. Our aim is to review the published literature on the use of 8-plates for deformity correction.

Methods

We conducted a systematic review on 8-plate growth modulation for coronal deformity correction. We carried out detailed literature search on PubMed, Google Scholar, EMBASE, and Cochrane databases. We analysed selected studies for patient demographics, rate of deformity correction, clinical outcome and complications.

Results

We identified seven studies using 8-plate for deformity correction involving 215 patients (350 Limbs). The mean age was 9.5 years (2-16 years M/F Ratio 1.1:1); underlying aetiology was Idiopathic in 33% and Pathological 67% cases. The deformities were successfully corrected in 196/215 patients (91.2%) and partial/no correction in 19/215 patients (8.8%). The mean time to correction was 15.3 Months (10.3-25) and follows up of 18.9 months (12.4-24). The deformity corrected at 1.28 °/month (0.93-1.53), lateral distal femoral angle changed at 0.87°/month (0.65-1.0) and medial proximal tibial angle changed at 0.72 (0.5-1). Complications were reported in 12/215 patients (5.6%) including hardware failure in 5, overcorrection/leg length difference in 5, infection 1 and stiffness 1. The rebound was reported in 8 patients (3.7%).

Conclusion

Growth modulation with 8-plates has high efficacy and low complications for deformity correction; and has been used widely across all paediatric age groups and aetiology. The literature is mostly retrospective and heterogeneous to develop age and aetiology specific recommendations.

Comparison of Percentile Weight Gain of Growth-Friendly Constructs in Early-Onset Scoliosis

STUDY DESIGN

Multicenter retrospective cohort.

OBJECTIVE

To compare improvement in nutritional status seen in early-onset scoliosis (EOS) patients following treatment with various growth-friendly techniques, especially in underweight patients (<20th weight percentile).

BACKGROUND

Thoracic insufficiency resulting from EOS can lead to severe cardiopulmonary disease. In this age group, pulmonary function tests are often difficult or impossible to perform. Weight gain has been used in prior studies as a proxy for improvement and has been demonstrated following VEPTR and growing rod implantation. In this study, we aim to analyze weight gain of EOS patients treated with four different spinal implants to evaluate if significant differences in weight percentile change exist between them.

METHODS

Retrospective review of patients treated surgically for EOS was performed from a multicenter database. Exclusion criteria were index instrumentation at >10 years old and <2 years' follow-up.

RESULTS

287 patients met the inclusion criteria and etiologies were as follows: congenital = 85; syndromic = 79; neuromuscular = 69; and idiopathic = 52. Average patient age at surgery was 5.41 years, with an average follow-up of 5.8 years. Preoperatively, 55.4% (162/287) fell below the 20th weight percentile. There was no significant difference in preoperative weight between implants (p = .77), or diagnoses (p = .25). Among this group, the mean change in weight percentile was 10.5% (range: -16.7% to 88.7%) and all implant groups increased in mean weight percentile at final follow-up. There were no significant differences in weight percentile change between the groups when divided by implant type (p = .17).

CONCLUSIONS

Treatment of EOS with growth-friendly constructs resulted in an increase in weight percentile for underweight patients (<20th percentile), with no significant difference between constructs.

LEVEL OF EVIDENCE

Level III.

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.

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.

Prediction of rebound phenomenon after removal of hemiepiphyseal staples in patients with idiopathic genu valgum deformity

AIMS

Our aim was to investigate the predictive factors for the development of a rebound phenomenon after temporary hemiepiphysiodesis in children with genu valgum.

PATIENTS AND METHODS

We studied 37 limbs with idiopathic genu valgum who were treated with hemiepiphyseal stapling, and with more than six months remaining growth at removal of the staples. All children were followed until skeletal maturity or for more than two years after removal of the staples.

RESULTS

On multivariate logistic regression analysis, the rate of correction, body mass index (BMI), age, and initial valgus angle were significantly associated with a rebound phenomenon. With those characteristics, a predictive model for rebound was generated using recursive partitioning analysis. Children with a rapid rate of correction had the most frequent and severe rebound phenomenon (incidence 79%, mean 4°), whereas those with a slow rate of correction had less rebound when they had low BMI (43%, 2°) and none when the BMI was ≥ 21 kg/m(2).

CONCLUSION

This is the first study to evaluate a predictive model for a rebound phenomenon after temporary hemiepiphysiodesis in children with idiopathic genu valgum. Cite this article: Bone Joint J 2016;98-B:1270-5.

Guided growth may not be the best option for knee valgus deformity in adolescent patients with Morquio-A

INTRODUCTION

Valgus deformity in knees is a common concern in Morquio-A patients, preceding premature arthrosis and pain leading to walking disability and loss of ambulatory status. Treatment alternative is the guided growth, but this is sometimes not applied on time. Due to short height reached on these patients, not all will benefit from guided growth surgery.

PURPOSE

The purpose of this study is to describe early results of physeal osteotomy for acute valgus correction in adolescent patients and those almost at height peak to achieve alignment.

METHODS

We perform the osteotomy in four knees of 10- and 14-year-old patients, fixed with Kirschner wires, and allow early weight bearing. This is compared with one patient who was managed by guided growth.

RESULTS

The average acute correction osteotomy was 39 degrees with intermalleolar distance of 350 and 240 mm. At final follow-up, this measure was reduced to 70 and 20 mm, respectively, with clinical valgus of 4° and 2°. For the patient with guided growth, she was operated at 10.2 years old and 36 months in follow-up; preoperative valgus was 28/24° with intermalleolar distance of 140 mm. At the end of follow-up, this distance was increased to 150 mm with clinical valgus of 18/22°. During this follow-up, none of the patients lost ambulatory status. As a part of multi-organic disease progression, none of the three patients completed the 6-min walking test at final follow-up.

CONCLUSIONS

This physeal osteotomy is a feasible and optimal option to achieve acute valgus correction on severe deformity when there is not enough remaining growth on adolescent Morquio-A patients, and may help reduce arthritis progression in adjacent joints.

Guided growth: mechanism and reversibility of modulation

In paediatric orthopaedics, deformities and discrepancies in length of bones are key problems that commonly need to be addressed in daily practice. An understanding of the physiology behind developing bones is crucial for planning treatment. Modulation of the growing bone can be performed in a number of ways. Here, we discuss the principles and mechanisms behind the techniques. Historically, the first procedures were destructive in their mechanism but reversible techniques were later developed with stapling of the growth plate being the gold standard treatment for decades. It has historically been used for both angular deformities and control of overall bone length. Today, tension band plating has partially overtaken stapling but this technique also carries a risk of complications. The diverging screws in these implants are probably mainly useful for hemiepiphysiodesis. We also discuss new minimally invasive techniques that may become important in future clinical practice.

The role of guided growth as it relates to limb lengthening

For decades, the classic indication for limb lengthening has been reserved for anisomelia that was expected to reach or exceed 5 cm at maturity. Epiphysiodesis was reserved for discrepancies in the 2-5 cm range. With the increasing sophistication of fixators, including rail, hexapod, and hybrid, complex deformities may be corrected simultaneously while moderate to extreme lengthening is achieved. More recently, iterations of telescoping intramedullary rods have further strengthened our armamentarium. Meanwhile, permanent epiphysiodesis techniques, both open and percutaneous, have yielded to more versatile and reversible tethering of one (angle) or both (length) sides of a physis. While the techniques of guided growth and callotasis seem to be diametrically opposed, they may be used in a tandem or complementary fashion, for the benefit of the patient. If treatment is undertaken during skeletal growth, one must be aware that issues remain regarding the accurate assessment of skeletal maturity and prediction of the ultimate outcome. Therefore, there is potential for over- or undercorrection. Reversible and serial guided growth now enable the surgeon to commence intervention at a comparatively young age, for the purpose of optimizing limb alignment and reducing the ultimate discrepancy. Frame application may be delayed or, in some cases, avoided altogether. With the limb properly aligned at the outset of lengthening, elective use of a telescoping intramedullary nail may now be favored over a frame accordingly.

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.

Correction of static axial alignment in children with knee varus or valgus deformities through guided growth: Does it also correct dynamic frontal plane moments during walking?

Malaligned knees are predisposed to the development and progression of unicompartmental degenerations because of the excessive load placed on one side of the knee. Therefore, guided growth in skeletally immature patients is recommended. Indication for correction of varus/valgus deformities are based on static weight bearing radiographs. However, the dynamic knee abduction moment during walking showed only a weak correlation to malalignment determined by static radiographs. Therefore, the aim of the study was to measure the effects of guided growth on the normalization of frontal plane knee joint moments during walking. 15 legs of 8 patients (11-15 years) with idiopathic axial varus or valgus malalignment were analyzed. 16 typically developed peers served as controls. Instrumented gait analysis and clinical assessment were performed the day before implantation and explantation of eight-plates. Correlation between static mechanical tibiofemoral axis angle (MAA) and dynamic frontal plane knee joint moments and their change by guided growth were performed. The changes in dynamic knee moment in the frontal plane following guided growth showed high and significant correlation to the changes in static MAA (R=0.97, p<0.001). Contrary to the correlation of the changes, there was no correlation between static and dynamic measures in both sessions. In consequence two patients that had a natural knee moment before treatment showed a more pathological one after treatment. In conclusion, the changes in the dynamic load situation during walking can be predicted from the changes in static alignment. If pre-surgical gait analysis reveals a natural load situation, despite a static varus or valgus deformity, the intervention must be critically discussed.

Selective hemiepiphyseodesis for patellar instability with associated genu valgum

BACKGROUND/AIMS

Patellar instability limits activity and promotes arthritis. Correcting genu valgum with selective hemiepiphyseodesis can treat patellar instability.

METHODS

We retrospectively reviewed 26 knees with patellar instability and associated genu valgum that underwent hemiepiphyseodesis.

RESULTS

Average anatomic lateral distal femoral angle (aLDFA) significantly corrected. Symptoms improved in all patients. All competitive athletes returned to sports. One complication occurred.

CONCLUSIONS

In genu valgum, the patella seeks an abnormal mechanical axis, resulting in patellar instability. By correcting the mechanical axis with hemiepiphyseodesis, patellar instability symptoms improve and patients return to sports. Complications are rare. Selective hemiepiphyseodesis is recommended when treating patellar instability with associated genu valgum.

Combined distal tibial rotational osteotomy and proximal growth plate modulation for treatment of infantile Blount’s disease

Infantile Blount’s disease is a condition that causes genu varum and internal tibial torsion. Treatment options include observation, orthotics, corrective osteotomy, elevation of the medial tibial plateau, resection of a physeal bar, lateral hemi-epiphysiodesis, and guided growth of the proximal tibial physis. Each of these treatment options has its disadvantages. Treating the coronal deformity alone (genu varum) will result in persistence of the internal tibial torsion (the axial deformity). In this report, we describe the combination of lateral growth modulation and distal tibial external rotation osteotomy to correct all the elements of the disease. This has not been described before for treatment of Blount’s disease. Both coronal and axial deformities were corrected in this patient. We propose this combination (rather than the lateral growth modulation alone) as the method of treatment for early stages of Blount’s disease as it corrects both elements of the disease and in the same time avoids the complications of proximal tibial osteotomy.

Use of the eight-Plate for angular correction of knee deformities due to idiopathic and pathologic physis: initiating treatment according to etiology

PURPOSE

Angular deformities of the knee resulting from idiopathic, congenital, or acquired causes are commonly encountered in pediatric orthopedics. Whereas physiological deformities should be treated expectantly, the remaining often progress enough to warrant operative treatment, despite attempted bracing. Historical methods of surgical treatment (e.g., epiphysiodesis and stapling) have yielded to the increasingly popular method of reversible guided growth using the eight-Plate.

METHODS

We studied 58 patients with knee angular deformities managed with eight-Plate guided growth. All etiologies except physiological deformities and those with very slow growth rate were included. Each patient was under appropriate medical management during the entire duration of treatment and after plate removal.

RESULTS

In the dysplasia/syndrome group, we noted complete correction in 22 patients (78.5%), partial correction in 5 (17.9%), and no correction in 1 patient (3.6%). All cases of idiopathic deformities resolved. Patients with osteochondral dysplasias and genetic syndromes underwent earlier intervention and slower correction than those with idiopathic genu varum or valgum. The time difference in reaching a neutral mechanical axis between the two groups (11 months in idiopathic versus 18 months in pathological physis) could be explained by a significant difference in growth speeds (P = 0.003).

CONCLUSION

Results indicate that early intervention is advisable for patients with osteochondral dysplasias/syndromes as subsequent correction takes longer. If rebound growth causing recurrent deformity occurs, guided growth can be safely repeated. Additionally, complications reported with other techniques such as hardware failure, physeal violation by the implant, premature physeal closure, and overcorrection were not reported while using the eight-Plate.