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

Case Report: Surgical timing for Blount's disease: a case report and systematic review

Background

Currently, Blount's disease is treated in a variety of ways, but the optimal timing of treatment and the choice of optimal treatment regimen have yet to be determined. We report a case of a patient who failed multiple surgical treatments and underwent 3D-printed osteotomy guide-assisted proximal tibial orthopedic external fixation in adulthood to restore normal lower limb mechanical axis and suggest optimal treatment modalities in light of the systematic literature.

Methods

A case of Blount's disease patient who was misdiagnosed and missed and underwent multiple surgical treatments was retrospectively studied. According to the PRISMA statement, a systematic review of electronic databases such as PubMed, Embase, and Web of Science was conducted to explore the optimal timing of surgery for Blount's disease from 2010.

Results

A boy born in 2001 was found to have a varus deformity in his left knee joint at the age of 2 years, which was not diagnosed. At the age of 7 years, he was diagnosed with Blount's disease and underwent multiple surgeries over the following years, all of which resulted in recurrences. At the age of 21 years, he underwent high osteotomy and external fixation of the proximal left tibia using a 3D-printed guide plate in our hospital. At present, the external fixation has been taken out, and the lower limb force line has recovered well. The timing and choice of treatment for Blount's disease are important for the patient's prognosis. The systematic review analyzed a total of 23 studies with a combined sample size of 679 cases, it provides recommendations for treatment strategies based on patient age.

Conclusion

The patient's age and degree of deformity are key in determining the timing and treatment plan. For patients with early-onset, who are under four years old, they may begin with a conservative treatment strategy, moving to a timely osteotomy if the initial approach proves ineffective. For patients with late-onset, 4-10 years old, there are no recommendations for definitive treatment at this time. Patients over 10 years old should have their bone age and growth potential evaluated, with epiphysiodesis recommended for those with a growth potential greater than 2 years and osteotomy recommended for those with less than 2 years to achieve a complete correction of the deformity.

Tension-Band Plating for Infantile Blount Disease: Efficacy and Outcomes Comprehensive Review

Infantile Blount disease (IBD) is a pathologic varus knee deformity that, if left untreated, can lead to abnormal gait, limb length discrepancy, and pain. Traditionally, bracing and tibial osteotomy have been the primary treatments. More recently, guided growth with tension-band plating (TBP) has gained popularity, although there is a lack of data stratifying between the infantile, juvenile, and adolescent disease types. Therefore, the present review aims to determine the efficacy and complications of TBP in the IBD population. A systematic review was conducted following the PRISMA guidelines. Eligible studies included those focused on guided growth correction for IBD. Studies that did not stratify subjects by subgroup (infantile, juvenile, and adolescent) within their analysis were excluded. The outcomes of interest included demographic information, correction rate, failure rate, recurrence rate, and postoperative complications. Database review identified 541 studies. After screening, seven studies met our inclusion criteria, all of which were retrospective observational studies published between 2012 and 2022. In total, 92 limbs afflicted with Infantile Blount Disease underwent treatment with TBP. The recorded follow-up period ranged from four months to eight years. The age of patients at the time of surgery varied from 1.8 to nine years. On average, there was a 78.99% correction of deformities, with a range of 57.14% to 100%. Six studies provided data on failure and recurrence rates, with an average rate of 23.47%. Notably, infection and hardware failure emerged as the most prevalent postoperative complications, with mean rates of 11.44% and 9.50%, respectively. The average reoperation rate was 29.90%, with a range from 0.00% to 47.06%. The current literature shows a high rate of deformity correction with a relatively low risk of complications after TBP for IBD. Given the reported reoperation rates greatly varied, further data is needed to determine risk factors for reoperation following TBP. Our results suggest that guided growth with TBP may be a preferable first-line treatment for IBD.

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.

Predicting Success of Deformity Correction With Tension Band Plating in Early-Onset Tibia Vara

BACKGROUND

Angular deformity correction with tension band plating has not been as successful in early-onset tibia vara (EOTV) as it has been in other conditions. Our hypothesis is that perioperative factors can predict the success of lateral tibial tension band plating (LTTBP) in patients with EOTV.

METHODS

A retrospective review was performed at 7 centers evaluating radiographic outcomes of LTTBP in patients with EOTV (onset <7 y of age). Single-event tibial LTTBP outcome was assessed through medial proximal tibial angle (MPTA). The final limb alignment following comprehensive limb growth modulation (CLGM), which could include multiple procedures, was assessed by mechanical axis zone (MAZone), mechanical tibio-femoral angle (mTFA), and mechanical axis deviation (MAD). Preoperative age, weight, deformity severity, medial physeal slope, and Langenskiöld classification +/- modification were investigated as predictors of outcome. Success was defined as the correction or overcorrection to normal age-adjusted alignment. The minimum follow-up was 2 years except when deformity correction, skeletal maturity, or additional surgery occurred.

RESULTS

Fifty-two patients with 80 limbs underwent 115 tibial LTTBP procedures at a mean age of 5.3 y, including 78 primary, 21 implant revisions, and 15 reimplantations for recurrence. Tibial LTTBP resulted in a mean change of +8.6 o in MPTA and corrected 53% of tibias. CLGM resulted in MAD correction for 54% of limbs.Univariate analysis showed that success was best predicted by preoperative age, weight, MPTA, and MAD. Multivariate analysis identified that preoperative-MPTA/MAD and preoperative-weight<70 kg were predictive of MPTA and MAD correction, respectively. The probability of success tables are presented for reference.

CONCLUSION

Successful correction of MPTA to age-adjusted norms following a single-event LTTBP occurred in 53% of tibias and was best predicted by preoperative-MPTA and preoperative body weight <70 kg. Comprehensive growth modulation corrected limbs in 54%. The probability of correction to age-adjusted MAD is best estimated by preoperative-MAZone 1 or 2 (MAD ≤40 mm). Limbs with preoperative-MAD>80 mm improved, but ultimately all failed to correct completely with CLGM. Osteotomy may need to be considered with these severe deformities. While modified Langenskiöld classification and medial physeal slope have been shown to predict the outcome of osteotomy, they were not predictive for LTTBP. Change in MPTA was common after physeal untethering.

LEVEL OF EVIDENCE

Level-III.

Femoral Deformity in Tibia Vara and Its Response to Growth Modulation

BACKGROUND

While tibia vara is a disorder of the proximal tibial physis, femoral deformity frequently contributes to the overall limb malalignment. Our purpose was to determine how femoral varus deformity in tibia vara responds to growth modulation, with/without lateral tension band plating (LTBP) to the femur.

METHODS

One-hundred twenty-seven limbs undergoing LTBP for tibia vara were reviewed. All had tibial LTBP and 35 limbs also had femoral LTBP for varus. Radiographs were measured for correction of the mechanical lateral distal femoral angle (mLDFA) and mechanical axis deviation (MAD). Preoperative-femoral varus was defined with an age-adjusted guide: mLDFA >95 degrees for 2 to below 4 years and mLDFA >90 degrees for 4 to 18 years. The 35 limbs having femoral LTBP were compared with 50 limbs with femoral varus and no femoral LTBP. In addition, 42 limbs that did not have preoperative-femoral varus were followed. Patients with early-onset (below 7 y) tibia vara were compared with those with late-onset (≥8 y). Outcome success was based on published age-adjusted mLDFA and MAD norms.

RESULTS

Following femoral LTBP, the mean mLDFA decreased from 98.0 to 87.1 degrees. All femurs had some improvement, with 28/35 femurs (80%) achieving complete correction. One limb, with late follow-up, overcorrected, requiring reverse (medial) femoral tension band plating.For the 50 limbs with femoral varus and only tibial LTBP, 16/22 limbs (73%) with early-onset and 11/28 limbs (39%) with late-onset completely corrected their femoral deformities. If the limb had preoperative-femoral varus, femoral LTBP statistically correlated with successful mLDFA correction and improvement of MAD, only in the late-onset group.Forty-two limbs, without preoperative-femoral varus, had no change in their mean mLDFA of 87 degrees. However, 4 femurs (10%) ended with posttreatment varus.

CONCLUSIONS

Femoral LTBP is effective in correcting femoral varus deformity in the tibia vara. For femoral varus associated with late-onset tibia vara, femoral LTBP should be considered. Those that had femoral LTBP had statistically more successful femoral and overall limb varus correction. However, in early-onset tibia vara, with associated femoral varus, observation is warranted because 73% of femurs are corrected without femoral intervention. This study was underpowered to show additional improvement with femoral LTBP in the early-onset group. Even limbs with normal femoral alignment, should be observed closely for the development of femoral varus, during tibial LTBP treatment for tibia vara.

LEVEL OF EVIDENCE

Level III.

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

PURPOSES

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

METHODS

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

RESULTS

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

CONCLUSION

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

[Juvenile osteochondrosis and osteonecrosis]

BACKGROUND

Juvenile osteonecrosis is an important topic in orthopedics. A wide variety of body regions of the growing patient are affected, predominantly during adolescence. All are characterized by a usually unknown aetiology as well as a stadium-like course. The main problem is a local osseous circulatory disorder, which causes osteonecrosis.

RISK FACTORS

Mechanical overloading due to increased body weight, axial misalignment, and sports activity is discussed as a risk factor. Healing depends on the localization and extent of the osseous necrosis.

DIAGNOSTICS

Diagnostically, radiologic imaging is used, in which the typical bony remodeling can be followed.

THERAPY

The therapeutic procedure depends on the affected region but is usually accompanied by a reduction of mechanical loading. If the clinical and radiological findings worsen, surgical treatment must be considered. The recognition and treatment of juvenile osteonecrosis is important and significantly influences the further development of the patient.

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 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.

Guided growth: indications and techniques for correction of knock knees and bowlegs

PURPOSE OF REVIEW

Lower extremities axis alterations are a frequent cause for consultation in the medical practice of the care of paediatric patients. When it corresponds to pathological situations, guided growth surgery has been positioned as a possibility of well tolerated, reproducible and predictable resolution. For this reason, its use has increased significantly in recent years. In this review, its current indications, preoperative study, results and complications described in the updated literature will be discussed.

RECENT FINDINGS

The success of the technique remains high in the current literature, expanding the technique to other segments and disorders, and describing new ways of performing tension band with sutures. In addition, there is an increase in its incidence and a decrease in the associated hospitalized days, which can associate with techniques of lower morbidity.

SUMMARY

As guided growth surgery allows for successful correction of axis alterations, to achieve this, it is important to know the main indications, preoperative analysis and theoretical bases on which this technique is based, to carry it out in an adequate and timely manner, seeking an adequate resolution of the child's problem.

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.

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.

Predictive Factors for Recurrence in Infantile Blount Disease Treated With Tibial Osteotomy

BACKGROUND

This study aimed to determine the recurrence rate in infantile Blount disease (IBD) in a cohort of patients treated with a tibial osteotomy; and also to identify which factors were associated with recurrence.

METHODS

We reviewed the records of 20 patients, under the age of 7 years, with IBD (35 involved extremities) treated by proximal tibial realignment osteotomy to physiological valgus at a single institution over 4 years. We then analyzed the data to determine the rate of recurrence and identify the risk factors for recurrence.

RESULTS

The mean age of the included patients was 4.2 years (range, 2 to 6 y). We observed a recurrence rate of 40% (n=14) at a mean follow-up of 42 months (range, 21 to 72 mo). Knee instability [odds ratios OR, 6.6; 95% confidence interval (CI), 2.0-22.2], Langenskiöld stage (OR, 6.3; 95% CI, 2.0-19.4), and severity of the deformity, as measured by medial physeal slope (MPS) (OR, 1.2; 95% CI, 1.1-1.4), were associated with recurrence. On multiple logistic regression analysis, MPS remained the most relevant predictor of recurrence. Receiver operating curve analysis showed that an MPS ≥60 degrees predicted recurrence with a sensitivity of 79% and specificity of 95% (area under the curve=0.925). Postoperatively, increased varus alignment on weight-bearing as measured by the tibio-femoral angle was indicative of knee instability and associated with increased odds of recurrence (OR, 1.5; 95% CI, 1.1-1.9; P=0.004).

CONCLUSIONS

We observed a recurrence rate of 40% in children with IBD under 7 years treated with acute correction to a tibio-femoral angle of 5 to 10 degrees valgus through a dome proximal tibial osteotomy. Knee instability, Langenskiöld stage, and MPS were associated with recurrence. Cases with an MPS ≥60 degrees seem to be particularly at risk for recurrence. Further research is needed to validate these findings.

LEVEL OF EVIDENCE

Level IV.

Acute "three-in-one" surgery for the treatment of severe Blount's disease: Surgical technique and report of two cases

The treatment of Blount's disease has historically remained controversial. All the described techniques for its treatment have their own advantages and disadvantages, and no consensus has been reached on a single surgical approach. The aim of this report is to share the early results of a combination technique in which we have collated three well-known surgical steps in one procedure. This combined procedure is indicated for severe and recurrent cases. Our ‘three-in-one’ technique combines an intra-epiphyseal plateau elevating osteotomy with a tibial metaphyseal osteotomy and a lateral tibial temporary hemi-epiphysiodesis. We also report initial results of three limbs in two patients who were treated using this technique. The first case was that of an adolescent with severe left Blount's disease (Langenskiold stage IV) and a lateral thrust. The second case was that of bilateral severe infantile Blount's disease (Langenskiold stage V) and the infant had a lateral thrust. All measurements remarkably improved in both patients during the post-surgical assessment. The limb length discrepancy was 0.6 cm in the first case and 0.5 cm in the second. The preoperative internal tibial rotation and lateral thrust were corrected spontaneously. No complications were recorded in either patient. The three-in-one technique is a safe and versatile surgical approach that can be used in severe, refractory, and recurrent cases of open physis. Furthermore, it can potentially solve the problems of lateral thrust and internal tibial rotation. More cases should be studied before we can endorse the safety and effectiveness of this technique.