Screw Anterior Distal Femoral Hemiepiphysiodesis in Children With Cerebral Palsy and Knee Flexion Contractures: A Retrospective Case-control Study

Anterior Proximal Tibial Screw Hemiepiphysiodesis Decreases Posterior Tibial Slope in Knee Flexion Contracture: A Case Report

CASE

A 13-year-old adolescent boy with hemiplegic cerebral palsy suffering from fixed knee flexion deformity of 10° despite extensive conservative treatment. Owing to a posterior tibial slope (PTS) of 16°, anterior hemiepiphysiodesis was applied to the proximal tibia. The 2 screws were removed after 9 months. Final follow-up at 16 months showed complete knee extension and a PTS of 4°.

CONCLUSION

The presented technique is a good alternative in knee flexion deformity with an increased PTS and has surprisingly not been described in the literature. This might be worth considering for other pathologies such as pediatric anterior cruciate ligament injury with an increased PTS.

Anterior Distal Femoral Hemiepiphysiodesis in Children With Fixed Knee Flexion Deformities: Does Screw Position Matter?

BACKGROUND

Anterior distal femoral hemiepiphysiodesis (ADFH) using 2 percutaneous screws is an effective technique for the treatment of fixed knee flexion deformities in children with neuromuscular disorders. The role of sagittal screw position on the outcome of the procedure is unknown.

METHODS

This is a retrospective case series of patients who underwent ADFH at a single pediatric hospital from 2013 to 2020. Radiographs were evaluated for sagittal screw position and the associated change in lateral distal femoral physeal angle over time. The position of the 2 screws was classified as either being both in the anterior third of the physis (AA), one screw in the anterior third and the other screw in the middle third (AM), or both screws in the middle third of the physis (MM).

RESULTS

The study population included 68 knees in 36 patients. The mean physeal angle at the time of surgery was 93 degrees (SD 4.0 degrees), which increased to 102.4 degrees (SD 5.7 degrees) at 12 months, for a change of 9.4 degrees ( P <0.001). At 24 months, the mean physeal angle was 104.6 degrees (SD 6.3 degrees) for a further change of 2.9 degrees ( P <0.001). When stratified by screw position all screw configurations resulted in an increase in the physeal angle at 12 months. At the 24-month follow-up, the physeal angle in knees with AA screws continued to increase another 3.5 degrees ( P <0.05), there was a minimal change in knees with AM screws (1.47°, P >0.05) and knees with MM screws saw a reversal of physeal angle change (-7.1 degrees, P <0.05).

CONCLUSIONS

ADFH using percutaneous screws results in an increase in the lateral distal femoral physeal angle. The rate of correction is largest in the first 12 months after the procedure. As such, this procedure should be considered in patients with less than 2 years of growth remaining. However, initial screw positioning influences the amount of change over time, and close postoperative surveillance until physeal closure is essential for all patients.

LEVEL OF EVIDENCE

Level IV-retrospective case series.

Anterior Distal Femoral Hemiepiphysiodesis Does Not Change Pelvic Tilt in Children With Cerebral Palsy

BACKGROUND

Anterior distal femoral hemiepiphysiodesis (ADFH) is a surgical treatment choice to correct flexed knee gait and fixed knee flexion deformities in children with cerebral palsy who are skeletally immature. Increased anterior pelvic tilt has been reported after surgeries that correct knee flexion deformities, including hamstring lengthening (HSL) and distal femoral extension osteotomies, but anterior pelvic tilt has not been studied after ADFH. We hypothesized that anterior pelvic tilt would increase after ADFH, especially when combined with HSL, and it would correlate with the change in minimum knee flexion in stance and dynamic hamstring lengths.

METHODS

Thirty-four eligible participants (age: 13.0, SD: 2.0) were included. Change in mean pelvic tilt across the gait cycle was compared as a function of clinical and gait parameters using linear mixed models. The relationship of change in pelvic tilt to change in other variables was examined using Pearson correlation.

RESULTS

Overall, anterior pelvic tilt increased significantly after ADFH by 4.4 degrees ( P = 0.02). Further, the analysis revealed anterior pelvic tilt only increased significantly in the group that had concurrent HSL (11.1 degrees, P < 0.001). Overall, minimum knee flexion significantly decreased (increase in knee extension) in stance (-19.1 degrees, P < 0.001) and there was an increase in maximum normalized dynamic hamstring lengths (0.03, P < 0.001). The anterior pelvic tilt increased significantly in Gross Motor Function Classification System levels III to IV (5.9 degrees, P = 0.02) but did not change significantly in Gross Motor Function Classification System I to II (2.5 degrees, P = 0.37). Change in pelvic tilt was correlated with change in maximum dynamic hamstring lengths ( r = 0.87, P < 0.0001) and change in minimum knee flexion in stance ( r = -0.71, P < 0.0001).

CONCLUSIONS

Anterior distal hemiepiphysiodesis without concurrent HSL for flexion knee deformities does not result in increased anterior pelvic tilt. Surgeons should consider anterior distal hemiepiphysiodesis in patients with cerebral palsy and flexed knee gait, who preoperatively have long dynamically modeled hamstrings, are skeletally immature, and when maintenance of pelvic tilt is desired.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Crouch Gait in Cerebral Palsy: Current Concepts Review

Background and Objective

Crouch gait is the most common pathological gait pattern in cerebral palsy and is commonly seen in patients with spastic diplegia. It is characterized by excessive knee flexion throughout the stance phase of gait cycle. The aim of this review is to discuss the current literature about CG for a more comprehensive understanding.

Methods

A literature review about various aspects of crouch gait in cerebral palsy was undertaken. This included its etiology and pathophysiology, biomechanics in crouch gait, natural history of untreated crouch gait, clinical and radiological evaluation and different modalities of available treatment.

Results

The etiology is multifactorial and the pathophysiology is poorly understood. This makes its management challenging, thereby leading to a variety of available treatment modalities. Inadvertent lengthening of muscle-tendon units is an important cause and can be avoided. A meticulous clinical and radiological evaluation of patients, supplemented by observational and instrumented gait analysis is mandatory in choosing correct treatment modality and improving the treatment outcome. Younger children can be managed satisfactorily by various non-operative methods and spasticity reduction measures. However, crouch gait in cerebral palsy has a progressive natural history and surgical interventions are needed frequently. The current literature supports combination of various soft tissue and bony procedures as a part of single event multilevel surgery. Growth modulation in the form of anterior distal femur hemiepiphysiodesis for correction of fixed flexion deformity of knee has shown encouraging results and can be an alternative in younger children with sufficient growth remaining.

Conclusions

In spite of extensive research in this field, the current understanding about crouch gait has many knowledge gaps. Further studies about the etiopathogenesis and biomechanics of crouch using instrumented gait analysis are suggested. Similarly, future research should focus on the long term outcomes of different treatment modalities through comparative trials.

Prevalence of knee contractures is high in children with cerebral palsy in Denmark

INTRODUCTION

Cerebral palsy (CP) is a neurological disease occurring in children at early gestation, often resulting in pronounced functional limitations. A Swedish cross-sectional study (Cloodt, et al., 2018) discovered that 22% of children with CP had a knee contracture, which was associated with higher levels of Gross Motor Function Classification System (GMFCS), higher age, and higher levels of spasticity measured by the Modified Ashworth Scale (MAS). The current study investigated these associations in a Danish population.

METHODS

This is a cross-sectional study including 1,163 children with CP aged 0-15 years, registered in the Danish National Cerebral Palsy Registry between 2017 and 2019. Prevalence of knee contracture was estimated, and logistic regression analysis was applied with results presented as odds ratio (OR) with 95% confidence intervals (CI).

RESULTS

A total of 511 children with CP had knee contracture resulting in a prevalence of 44%. Age groups 4-6 years (OR: 1.73, CI: 1.19; 2.52), 7-9 years (OR: 1.85, CI: 1.29; 2.66) and 10-12 years (OR: 2.12, CI: 1.39; 3.24) were significantly associated with a higher prevalence of knee contractures compared to age group 0-3 years. Knee contractures were significantly more frequent at GMFCS levels IV (OR: 1.9, CI: 1.21; 2.97) and V (OR: 3.62, CI: 2.36; 5.55) compared to level I. Knee contractures were not associated with higher levels of MAS.

CONCLUSIONS

Knee contractures are highly prevalent and significantly associated with high levels of GMFCS and increased age until 12 years, but not with high levels of spasticity in children with CP in Denmark.

Guided Growth of the Proximal Femur for the Management of the 'Hip at Risk' in Children with Cerebral Palsy-A Systematic Review

BACKGROUND

Guided growth is frequently used to modify lower-limb alignment in children, and recently temporary medial hemiepiphysiodesis of the proximal femur (TMH-PF) has been used for the management of hips at risk of subluxation in cerebral palsy (CP) patients. The aim of our study was to evaluate the efficacy of TMH-PF in the management of neuromuscular hip dysplasia in children with cerebral palsy.

METHODS

A systematic search of the literature was performed by using PubMed, EMBASE, CINAHL, MEDLINE, Scopus and Cochrane databases. Pre- and postoperative radiographic changes of the migration percentage (MP), head-shaft angle (HSA) and acetabular index (AI) were included in a meta-analysis. Secondary outcomes were treatment complication rates, technical considerations and the limitations of this novel technique.

RESULTS

Four studies (93 patients; 178 hips) met the eligibility criteria for inclusion in the meta-analysis. All three radiographic measurements showed significant changes at a minimum of 2 years of follow-up. Mean changes for MP were 8.48% (95% CI 3.81-13.14), HSA 12.28° (95% CI 11.17-13.39) and AI 3.41° (95% CI 0.72-6.10), with I² of 75.74%, 0% and 87.68%, respectively. The serious complication rate was overall low; however, physeal 'growing off' of the screw was reported in up to 43% of hips treated.

CONCLUSION

TMH-PF is an effective and predictable method to treat CP patients with 'hips at risk', and the overall complication rate is low; however, further work is required to identify the best candidates and surgical timing, as well as choice of technique and implant.

[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.

Anterior distal femoral hemiepiphysiodesis in children with cerebral palsy: Establishing surgical indications and techniques using the modified Delphi method and literature review

PURPOSE

The purpose of this study was to develop consensus for the surgical indications of anterior distal femur hemiepiphysiodesis in children with cerebral palsy using expert surgeon opinion through a modified Delphi technique.

METHODS

The panel used a 5-level Likert-type scale to record agreement or disagreement with 27 statements regarding anterior distal femur hemiepiphysiodesis. Consensus was defined as at least 80% of responses being in the highest or lowest 2 of the Likert-type ratings. General agreement was defined as 60%-79% falling into the highest or lowest 2 ratings.

RESULTS

For anterior distal femur hemiepiphysiodesis, 27 statements were surveyed: consensus or general agreement among the panelists was achieved for 22 of 27 statements (22/27, 82%) and 5 statements had no agreement (5/27, 18%). There was general consensus that anterior distal femur hemiepiphysiodesis is indicated for ambulatory children with cerebral palsy, with at least 2 years growth remaining, and smaller (<30 degrees) knee flexion contractures and for minimally ambulatory children to aid in standing/transfers. Consensus was achieved regarding the importance of close radiographic follow-up after screw insertion to identify or prevent secondary deformity. There was general agreement that percutaneous screws are preferred over anterior plates due to the pain and irritation associated with plates. Finally, it was agreed that anterior distal femur hemiepiphysiodesis was not indicated in the absence of a knee flexion contracture.

CONCLUSION

Anterior distal femur hemiepiphysiodesis can be used to treat fixed knee flexion contractures in the setting of crouch gait, but other associated lever arm dysfunctions must be addressed by single-event multilevel surgery.

LEVEL OF EVIDENCE

V.

Functional and Clinical Outcomes of Combined Simultaneous Bilateral Anterior Distal Femoral Plate Hemiepiphysiodesis and Hamstrings Release in Management of Knee Flexion Contractures in Children With Neuromuscular Disorders

BACKGROUND

We examined the clinical and functional outcomes of the simultaneous anterior distal femoral 8-plate hemiepiphysiodesis (ADF8PH) and hamstring release, for fixed knee flexion deformity in children with neuromuscular disease. To our knowledge, no published evidence is available that reports the outcomes of this combined techniques.

METHODS

Electronic medical records were retrospectively reviewed for 19 consecutive children who underwent bilateral ADF8PH and concomitant hamstrings release in our institution from 2012 to 2019. Relevant demographics, Gross Motor Functional Classification Score and preoperative and postoperative knee flexion contractures and popliteal angles were documented.

RESULTS

The average age at the time of operation was 12±2.1 years. There were 15 males and 4 females. Diagnoses included cerebral palsy (n=16), Cornelia de Lange syndrome (n=1), hereditary spastic paraplegia type 56 (n=1) and fructose-1,6 bisphosphonate aldose B deficiency (n=1). Mean length of follow-up was 3.8 years (range: 1.5 to 7 y). Mean fixed knee flexion deformity improved from 28.9 to 13.4 degrees (P<0.001) at an average correction rate of 0.94 degrees per month. Mean popliteal angle improved from 81.8 to 44.4 degrees (P<0.001) in the early postoperative phase and to 51.8 degrees (P<0.001) in latest clinic review. Mean time to correction was 18.9 months. The agreed treatment goals of maintaining or promoting the use of standing frame and spinal/postural symmetry was attained in 18 patients (94.7%). Postoperative knee pain was reported in 2 cases (10.5%). We report 2 complications; 1 case of neurapraxia and 1 case of sepsis because of respiratory infection.

CONCLUSION

Simultaneous bilateral ADF8PH with hamstrings release is a promising effective technique for correction of knee flexion contractures in skeletally immature individuals with neuromuscular disabilities. Our findings demonstrate improvement in clinical outcomes and maintaining functional outcomes, indicating the validity of this approach as a satisfactory, less invasive alternative in the management of this deformity.

LEVEL OF EVIDENCE

Level IV-therapeutic study.