Video-Assisted Thoracoscopy for Vertebral Body Tethering of Juvenile and Adolescent Idiopathic Scoliosis: Tips and Tricks of Surgical Multidisciplinary Management

VATS (video assisted thoracoscopic surgery) is routinely and successfully performed in minor and major complex thoracic procedures. This technique has been recently introduced for the treatment of severe forms of idiopathic scoliosis (IS) with the aim to repair the deformity, reduce morbidity and to prevent its progression in patients with skeletal immaturity. This study aims to present VATS in anterior vertebral body tethering (AVBT) approach to support the pediatric orthopedic surgeons during vertebral body fixation. Surgical and anesthesiologic tips and tricks are reported to assure a safe procedure. The study includes preadolescents with IS and a grade of scoliosis >40° that had a high probability of deterioration due to remaining growth (December 2018 to April 2021). Skeletal immaturity of enrolled patients was assessed by Sanders classification and Risser sign. Patients had a Risser score between 0 and 1 and a Sanders score >2 and <5. AVBT technique using VATS was performed by a senior pediatric surgeon assisting the pediatric orthopedic surgeon. Twenty-three patients have been submitted to VATS AVBT in the period of study (age range 9–14 years). The patients had a classified deformity Lenke 1A or B convex right and all types of curves were treated. In all patients, the vertebrae submitted to tethering surgery ranged from D5 to D12; mean curve correction was 43%. Three postoperative complications occurred: one late postoperative bleeding requiring a chest tube positioning on 12th postoperative day; one screw dislodged and needed to be removed; one child showed worsening of the scoliosis and needed a posterior arthrodesis. Initial results of VATS AVBT in growing patients with spinal deformities are encouraging. An appropriate selection of patients and a pediatric dedicated multidisciplinary surgical approach decrease intraoperative complications, time of operation and postoperative sequelae and guarantee an optimal outcome.

Correlation of Femoral Trochlear Dysplasia With Anterior Cruciate Ligament Injury in Skeletally Immature Patients

Background: Reports of anterior cruciate ligament (ACL) injury in patients with skeletal immaturity have been increasing. Variations in knee joint anatomy have been linked to ACL injury risk factors. Purpose: To identify associations between ACL injury, patella alta, and femoral trochlear dysplasia in patients with skeletal immaturity by using magnetic resonance imaging (MRI). Study Design: Cross-sectional study; Level of evidence, 3. Methods: This retrospective study included 231 patients with skeletal immaturity—116 with acute complete noncontact ACL injury and 115 without ACL injury (controls)—who underwent knee MRI. Cases of femoral trochlear dysplasia were divided into 4 types according to the Dejour classification scheme. Patellar height and patellar tendon length were measured via sagittal MRI, and the Insall-Salvati ratio (ISR) was calculated. Results: In the ACL injury group, 56 (48.3%) knees exhibited trochlear dysplasia, including 51 (91.1%) that were Dejour type A; and in the control group, 12 (10.4%) knees exhibited trochlear dysplasia, 12 (100%) Dejour type A. The prevalence of femoral trochlear dysplasia was significantly higher in the ACL injury group than in the control group ( P < .001). The ISR was not significantly different between the ACL injury and control groups (0.9 ± 0.2 vs 1 ± 0.2 mm; P = .16). The correlation between ISR >1.2 and presence of ACL injury was not significant. Conclusion: Femoral trochlear dysplasia was associated with ACL injury in patients with skeletal immaturity. In particular, Dejour type A femoral trochlear dysplasia was correlated with ACL injury patients with skeletal immaturity. Also, the possibility of ACL damage exists in patients with skeletal immaturity and femoral trochlear dysplasia.

Tratamento cirúrgico de lesão do ligamento cruzado anterior em paciente com imaturidade esquelética pela técnica de Kocher, com seguimento pós operatório de 6 anos: relato de caso / Surgical treatment of anterior cruciate ligament injury in a patient with skeletal immaturity by the Kocher technique, with a postoperative follow-up of 6 years: case report

Introdução: No tratamento cirúrgico da lesão do ligamento cruzado anterior (LCA) em pacientes pediá-tricos, é necessário o equilíbrio entre a restauração da anatomia, e o risco de dano à fise de crescimento durante o ato operatório. Objetivo: Relatar caso de paciente com 9 anos, de-senvolvimento puberal de Tanner I, submetido a reconstrução do LCA pela técnica de Ko-cher, técnica de reconstrução extra fisária com enxerto de trato iliotibial autólogo.Palavras chave: Joelho, Reconstrução do ligamento cruzado anterior, Maturidade sexual AbstractIntroduction: In the surgical treatment of anterior cruciate ligament (ACL) injury in pediatric patients, a balance between anatomical restoration and the risk of damage to the growth plate during the surgery is necessary. Objective: Report a case of a 9-year-old patient, pubertal development of Tanner I, underwent ACL reconstruction using the technique of Kocher et al., a physeal-sparing reconstruction technique with autologous iliotibial tract graft.Keywords: Knee, Anterior cruciate ligament reconstruction, Sexual maturation

Risk Factors for Recurrent Anterior Shoulder Instability after Arthroscopic Stabilization in Adolescent Athletes

Objectives: Arthroscopic stabilization has become the preferred surgery for adolescent athletes with anterior instability without significant bone loss. Although successful for most patients, 10-40% will experience recurrent instability. The purpose of the current study was to compare a consecutive series of patients who had failed an arthroscopic stabilization to an age and gender matched cohort of patients who had no evidence of recurrent instability with a goal of identifying risk factors for future instability. Methods: A retrospective review was undertaken of all patients undergoing an arthroscopic shoulder stabilization for anterior instability between 2009 and 2016. Patients over the age of 18 years and those with underlying syndromes affecting the musculoskeletal system were excluded. Two patient cohorts were identified: (1) Patients with recurrent instability (frank dislocations or subluxations) after their arthroscopic stabilization; (2) An age and gender matched cohort of patients with no recurrent instability at a minimum of 2 years follow-up from surgery. Patient demographic, injury, radiographic, and surgical variables were recorded. In particular, bone loss measurements were performed on both the glenoid and humerus, and Hill-Sachs lesions were classified as “on-track” or ”off-track”. Variables at p<0.10 on univariate analysis were entered into a binary logistic multivariate regression analysis. Results: 35 patients were identified that failed an arthroscopic stabilization at a mean of 1.2 ± 1.0 years after their index surgery. A separate age and gender matched cohort of 35 patients was also identified with no symptoms of recurrent instability. Univariate analysis identified the following 4 risk factors for recurrent instability (glenoid bone loss > 10%, glenoid retroversion < 5◦, skeletal immaturity, and patients with more than one pre-surgical instability event). Collision sport participation, the presence and size of a Hill-Sachs deformity, and the glenoid track were not predictive of failure. Multivariate regression analysis revealed that loss of glenoid retroversion, skeletal immaturity, and a greater number of prior instability events best predicted future recurrence with two risk factors having a 3x increased risk and patients with all three risk factors having a 4x increased risk of recurrent instability after arthroscopic stabilization. Conclusion: Anterior glenoid bone loss, glenoid version, skeletal immaturity, and multiple pre-operative instability events are risk factors for failed arthroscopic stabilization in adolescent athletes with anterior instability. In the setting of multiple risk factors, patients and families should be counselled of the increased odds of surgical failure and other forms of surgical stabilization may need to be considered.

Prevalence of toe symphalangism in Hong Kong Chinese population

Objective: To explore the prevalence and variations of toe symphalangism in the Hong Kong Chinese population. Methods: A retrospective review of foot radiographs taken in Chinese adult patients admitted to United Christian Hospital from 1 January, 2016 to 31 December, 2016. Exclusion criteria include (1) previous toe amputation, (2) skeletal immaturity, (3) severe deformity, and (4) repeated attendance. The frequencies were compared by χ 2 test. Result: A total of 1364 foot radiographs were reviewed. Six-hundred sixty radiographs were excluded. A total of 704 radiographs were included in this study. There were total 849 feet reviewed (left: 290, right: 269, bilateral: 145). Their mean age (± standard deviation) was 59.5 ± 14.2 years. The prevalence of 2nd, 3rd, 4th, and 5th toe symphalangism was 0.2%, 0.8%, 9.9%, and 76.7%, respectively. The prevalence resembles Asian population. There was no significant difference in the prevalence associated with the following factors: (1) gender and (2) left versus right foot. There was no 4th toe symphalangism without 5th toe involvement. In the 145 bilateral feet radiographs, asymmetrical distribution of toe symphalangism was found in 8.2%. Second toe symphalangism is rare (0.24%). Conclusion: This is the first study in Hong Kong to report prevalence of toe symphalangism in Chinese population. There is a high prevalence rate of 5th toe symphalangism in the Hong Kong Chinese Population. This implies less flexible lesser toes in the Chinese population with higher risks of development of deformities. The clinical implication of such findings needs further research.

Comparison of Vickers’ Physiolysis With Osteotomy for Primary Correction of Clinodactyly

Background: The purpose of this study was to compare the Vickers physiolysis procedure with osteotomy for correction of digital clinodactyly and determine which method provides better correction at final follow-up or whether the patient’s age, preoperative angulation, or presence of syndactyly affects final outcomes. Methods: All patients of skeletal immaturity who underwent surgical correction of clinodactyly were evaluated with clinical examination and radiographs to determine the percentage and absolute change in the degree of clinodactyly pre- versus postoperatively, in addition to stratification based on the degree of deformity, age, and presence of syndactyly. Results: Vickers’ physiolysis and osteotomy were undertaken in 30 and 11 digits, respectively. The angulation significantly improved from 43.0° to 23.9°, with a 46.2% correction of deformity in the Vickers group at 46.3 months. The angulation decreased from 39.2° to 22.4° in the osteotomy group, with a 55.3% correction of deformity at 55.3 months. There was better correction in those with isolated clinodactyly compared with those with concomitant syndactyly and better percentage of correction in patients with lesser deformity in the Vickers group. There were more reoperations in the osteotomy group. Conclusions: The use of osteotomy may lead to more revision cases, whereas the Vickers procedure has minimal complications and need for revision. The Vickers physiolysis procedure is more effective in those with angulation <55°.

Risk of Redislocation After Primary Patellar Dislocation: A Clinical Prediction Model Based on Magnetic Resonance Imaging Variables

Background: First-time lateral patellar dislocations have historically been treated with a nonoperative approach; a clinical tool to predict patients who are most likely to redislocate may have clinical utility. Purpose: (1) To determine if there are discriminating factors present between patients who redislocated their patellas and those who did not after a first-time lateral patellar dislocation and (2) to use this information to develop a model that can predict the recurrence risk of lateral patellar dislocation in this population. Study Design: Case-control study; Level of evidence, 3. Methods: The study population included those with first-time lateral patellar dislocation, magnetic resonance imaging within 6 weeks, and 2-year minimum follow-up. Cohort A was from a prospective study with 2-year follow-up. Cohort B was a prospectively identified cohort with retrospective chart review. Follow-up was obtained clinically or via mail for patients without 2-year clinical follow-up. Results: Sixty-one patients (42%) out of 145 with primary lateral patellar dislocation had recurrent dislocation within 2 years. Stepwise logistic regression analysis demonstrated that skeletal immaturity (odds ratio, 4.05; 95% CI, 1.86-8.82; P = .0004), sulcus angle (odds ratio, 4.87; 95% CI, 2.01-11.80; P = .0005), and Insall-Salvati ratio (odds ratio, 3.0; 95% CI, 1.34-6.70; P = .0074) were significant predictors of redislocation. Receiver operator characteristic curves defined the cut points to be sulcus angle ≥154° and Insall-Salvati ratio ≥1.3. The probability of redislocation based on the presence of factors was 5.8% with no factors present and 22.7% with any 1 factor present, increasing to 78.5% if all 3 factors were present. Conclusion: This model demonstrates a high risk of lateral patellar redislocation when a patient presents with skeletal immaturity as well as magnetic resonance measurements of sulcus angle ≥154° and patellar height as measured by Insall-Salvati ratio ≥1.3. A patient will have a low risk of lateral patellar redislocation with the inverse findings.

New insights into the biomechanics of Legg-Calvé-Perthes’ disease

Objectives Legg–Calvé–Perthes’ disease (LCP) is an idiopathic osteonecrosis of the femoral head that is most common in children between four and eight years old. The factors that lead to the onset of LCP are still unclear; however, it is believed that interruption of the blood supply to the developing epiphysis is an important factor in the development of the condition. Methods Finite element analysis modelling of the blood supply to the juvenile epiphysis was investigated to understand under which circumstances the blood vessels supplying the femoral epiphysis could become obstructed. The identification of these conditions is likely to be important in understanding the biomechanics of LCP. Results The results support the hypothesis that vascular obstruction to the epiphysis may arise when there is delayed ossification and when articular cartilage has reduced stiffness under compression. Conclusion The findings support the theory of vascular occlusion as being important in the pathophysiology of Perthes disease. Cite this article: M. Pinheiro, C. A. Dobson, D. Perry, M. J. Fagan. New insights into the biomechanics of Legg-Calvé-Perthes’ disease: The Role of Epiphyseal Skeletal Immaturity in Vascular Obstruction. Bone Joint Res 2018;7:148–156. DOI: 10.1302/2046-3758.72.BJR-2017-0191.R1.

Natural History of Postoperative Adding-On in Adolescent Idiopathic Scoliosis: What Are the Risk Factors for Progressive Adding-On?

Purpose. To investigate the natural history of distal adding-on in adolescent idiopathic scoliosis (AIS) and to identify risk factors for its progression. Methods. Sixty-one AIS patients with distal adding-on occurrence were included. We further classify distal adding-on into progressive and nonprogressive group according to its natural evolution. The first radiograph indicating initiation of adding-on (primary adding-on) and the last follow-up radiograph were compared in terms of the deviation of the first vertebra below instrumentation from the CSVL and the angulation of the first disc below instrumentation. Compared to primary adding-on, progressive adding-on was defined as a further increase of deviation > 5 mm or a further increase of angulation > 5°. Risk factors associated with the progression of adding-on were analyzed. Results. Among 61 patients diagnosed with distal adding-on, 24 (39.3%) were progressive and 37 (60.7%) were nonprogressive. Lower Risser grade, open triradiate cartilage, and lowest instrumented vertebra (LIV) proximal to Substantially Stable Vertebra (SSV) were found to be significantly associated with the progressive adding-on. Besides, the distal adding-on was more likely to progress for patients with higher left shoulders than right ones after surgery. Conclusions. The risk factors for the progression of adding-on included skeletal immaturity, LIV proximal to SSV, and higher left shoulders after surgery.