Transcultural adaptation and validation of a Korea version of Pedi-IKDC questionnaire

BACKGROUND

This study aimed to translate and transculturally adapt the English version of the Pedi-IKDC questionnaire into Korean and evaluate the psychometric properties of the Korean Pedi-IKDC questionnaire in terms of internal consistency, feasibility (floor and ceiling effect), construct validity, test-retest reliability, and factor analysis.

METHODS

The original English version of the Pedi-IKDC questionnaire was translated and transculturally adapted into Korean according to established guidelines. A total of 239 patients aged 7-18 years who visited the hospital because of knee pain or discomfort were considered eligible for the study. These patients completed the Korean version of the Pedi-IKDC and Pediatric Quality of Life questionnaires (PedsQL). The correlation between the PedsQL and Pedi-IKDC questionnaires was assessed to confirm the validity of the questionnaire. To verify the validity of the Korean Pedi-IKDC questionnaire, internal consistency, feasibility, test-retest reliability, and construct validity were evaluated, and a factor analysis was performed.

RESULTS

Internal consistency was found to be satisfactory in all subscales (Cronbach's alpha ≥ 0.7). The test-retest reliability was satisfactorily high for all subscales (Intraclass correlation coefficient: 0.81-0.84). A high correlation was observed between the total Pedi-IKDC score and the score on the physical-health subscale of child version of the PedsQL (Correlation coefficients: 0.720). There were no floor effects in all subscales, but ceiling effects were observed in four questions. Additionally, factor analysis suggested that the questionnaire could be divided into two subscales.

CONCLUSION

The Korean version of the Pedi-IKDC questionnaire was successfully translated and transculturally adapted according to the established guidelines. The Korean Pedi-IKDC questionnaire has been proven reliable and valid.

One Year Radiographic Response Following Prostrate SBRT: An Exploratory Analysis of a Phase III Randomized Trial

PURPOSE/OBJECTIVE(S)

Radiographic MRI response following prostate radiotherapy, particularly stereotactic body radiotherapy (SBRT), remains poorly understood. Our objective was to describe radiographic changes to the prostate gland and prostate tumor following SBRT of men treated on a prospective, randomized trial.

MATERIALS/METHODS

MIRAGE (NCT04384770) is a single center, randomized phase III trial of patients receiving either CT or MRI guided SBRT for localized prostate cancer. Patients underwent pre-treatment and annual post-treatment MRIs, in addition to routine PSA surveillance. Outcomes reported include percent gland shrinkage, percent PSA response at one year, and presence of residual tumor based on radiographic interpretation. Patient characteristics were compared via two-sample t-test or Fischer's exact test. Both univariate and multivariable logistical analysis were employed to identify potential clinical predictors of residual tumor on 1-year follow up MRI.

RESULTS

This study cohort included 94 eligible patients with baseline characteristics in Table 1. Residual lesions were seen in 13 patients (14%), 5/27 (18.5%) treated without ADT and 8/67 (12%) with ADT. PSA ablation was deep, with a 79% median decrease without ADT and 98% median decrease with ADT. Patients receiving ADT showed more gland shrinkage (17% vs. 34% shrinkage, p = 0.0001), while radiographic non-responders and responders experienced similar gland shrinkage (median 21% vs 29% shrinkage, p > 0.05). No significant clinical predictors of residual tumor were identified on univariate and multivariate analysis. No patient had any clinical or biochemical evidence of failure.

CONCLUSION

A total of 14% of patients were found to have residual tumor detected on MRI one year after SBRT. These data highlight the protracted nature of radiographic tumor response to radiation therapy, even with ablative radiation techniques. The analysis is limited by the lack of biopsy data to quantify whether visualized residual tumor harbor active cancer.

Comparison of Functional and Cosmetic Outcomes According to Fracture Level in Gartland Type III Pediatric Supracondylar Humerus Fractures

Background

Supracondylar humerus (SCH) fractures in children have been traditionally categorized according to the Wilkins-modified Gartland classification scheme, which is solely based on the degree of displacement. As this classification does not consider fracture patterns in the coronal or sagittal plane, the relationship between the fracture pattern and prognosis in SCH fractures remains unclear. Therefore, the purpose of this study was to evaluate the relationship between the fracture level and prognosis of pediatric SCH fractures.

Methods

Medical records and radiographs of 786 patients with SCH fractures who underwent surgical treatment between March 2004 and December 2017 were reviewed. A total of 192 patients were included in this study. Anteroposterior elbow radiographs taken at the time of injury were evaluated to obtain the level of fracture. Functional outcomes were evaluated based on modified Flynn grading at the last follow-up.

Results

Of 192 patients included in this study, 24 (12.1%), 148 (74.8%), and 20 (10.1%) had fractures in zone 1 (metaphyseal-diaphyseal area), zone 2 (between zones 1 and 3), and zone 3 (metaphyseal-epiphyseal area), respectively. There were significant differences in age at the time of injury (p = 0.011), direction of fracture displacement (p = 0.014), and loss of carrying angle (p < 0.001) between fractures in zone 3 and those in zone 1 or zone 2. Zone 3 fractures and classic zone 2 fractures also showed significant difference in outcomes, with zone 3 fractures having more unsatisfactory outcome than classic zone 2 fractures (p = 0.049).

Conclusions

For SCH fractures, varus deformity of the elbow was more common in zone 3 (metaphyseal-epiphyseal area) than in the other zones. Thus, pediatric orthopedic surgeons should be mindful of the possibility of cubitus varus deformity when treating SCH fractures in zone 3. A thorough postoperative follow-up is required.

Anatomic consideration of the radial nerve in relation to humeral length for unilateral external fixation: a retrospective study using magnetic resonance imaging findings in korean

BACKGROUND

This study aimed to present a safe zone for distal pin insertion for external fixation using magnetic resonance imaging (MRI) images.

METHODS

All patients who took at least one upper arm MRI from June 2003 to July 2021 were searched via a clinical data warehouse. For measuring the humerus length, proximal and distal landmarks were set as the highest protruding point of the humeral head and lowermost margin of ossified bone of the lateral condyle, respectively. For children or adolescents with incomplete ossification, the uppermost and lowermost ossified margin of the ossification centers were set as proximal and distal landmarks respectively. The anterior exit point (AEP) was defined as the location of the radial nerve exiting the lateral intermuscular septum to the anterior humerus and distance between the distal margin of the humerus and AEP was measured. The proportions between the AEP and full humeral length were calculated.

RESULTS

A total of 132 patients were enrolled for final analysis. The mean humerus length was 29.4 cm (range 12.9-34.6 cm). The mean distance between the ossified lateral condyle and AEP was 6.6 cm (range 3.0-10.6 cm). The mean ratio of the anterior exit point and humeral length was 22.5% (range 15.1-30.8%). The minimum ratio was 15.1%.

CONCLUSION

A percutaneous distal pin insertion for humeral lengthening with an external fixator may be safely done within 15% length of the distal humerus. If pin insertion is required more proximal than distal 15% of the humeral shaft, an open procedure or preoperative radiographic assessment is advised to prevent iatrogenic radial nerve injury.

Normative Values of Tibial Tubercle-Trochlear Groove Distance and Tibial Tubercle-Posterior Cruciate Ligament Distance in Children

BACKGROUND

Patellar instability is a common knee pathology in skeletally immature patients. In skeletally mature populations, a tibial tubercle-trochlear groove (TT-TG) distance of ≥20 mm is generally considered a pathological value. However, as pediatric patients grow and as the TT-TG distance varies with age, applying the same cutoff value as adult patients to them is unreasonable.

PURPOSE/HYPOTHESIS

This study aimed to analyze the normative values of the TT-TG and tibial tubercle-posterior cruciate ligament (TT-PCL) distances in children with no patellofemoral instability and to propose the cutoff value of the TT-TG and TT-PCL distances predictive of increased risk of patellofemoral instability in pediatric patients. We hypothesized that the TT-TG and TT-PCL distances increase with age in children and adolescents.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Magnetic resonance imaging scans of the knee were collected from the patellar instability group and the control group. The TT-TG and TT-PCL distances were measured. The normalized values of the TT-TG and TT-PCL distances were calculated by dividing them by the femoral width. Segmented analysis with 1 breakpoint was performed for both the TT-TG and the TT-PCL distances. The optimal cutoff values of the TT-TG and TT-PCL distances were calculated by maximizing the sum of the sensitivity and specificity.

RESULTS

A total of 87 patients had patellar instability, and 509 patients did not. The median values of TT-TG and TT-PCL distances in the control group (8.18 mm and 19.48 mm, respectively) were significantly smaller than those in the instability group (16.10 mm and 24.41 mm, respectively). For those aged <15 years, the TT-TG distance significantly increased by 0.39 mm as the age increased by 1 year. The TT-PCL distance increased by 1.14 mm/year until the age of 11 years. In our cohort, the cutoff value of the TT-TG distance of 14.90 mm yielded 66% sensitivity and 81.9% specificity for predicting an increased risk of patellar instability. The cutoff value of the TT-PCL distance of 23.68 mm yielded 63.9% sensitivity and 65.3% specificity for predicting an increased risk of patellar instability.

CONCLUSION

In our cohort of 596 participants, we have documented the normative values of the TT-TG and TT-PCL distances in children aged <20 years. During the surgery for patellar instability in pediatric patients, orthopaedic surgeons should consider the normative values of the TT-TG and TT-PCL distances according to age to determine which patients need distal realignment surgery.

Epidemiology and demographics of slipped capital femoral epiphysis in South Korea: A nationwide cohort study

BACKGROUND

This study investigated the epidemiology and demographics of slipped capital femoral epiphysis (SCFE) in South Korea using a nationwide population-based database.

METHODS

Information on sex, age at onset, endocrine comorbidities, history of growth hormone therapy, history of radiation therapy, surgical methods, and complications in patients with SCFE aged younger than 18 years between 2007 and 2019 was retrieved from the Korean Health Insurance Review and Assessment Service database.

RESULTS

Data were available for 586 children (429 boys, 157 girls). The average age at onset was 11.1 ± 1.8 years (boys, 11.3 ± 1.9; girls, 10.6 ± 1.5). Five hundred and twenty-nine (90.3%) patients were aged 9-14 years; the incidence rate in this age group was 6.0/100,000 (95% confidence interval, 5.5-6.6) and significantly higher in boys (8.4 vs 3.5, p<0.001). There was a significant increase in the annual incidence rate from 0.96/100,000 in 2009 to 2.05/100,000 in 2019 (p = 0.006). Ninety-five patients (16.2%) had endocrine comorbidities or a history of hormone/radiation therapy. Osteotomy and internal fixation were performed in 59 patients and in situ pinning in 527. Seventy-six patients developed postoperative complications.

CONCLUSION

The annual incidence rate of SCFE in South Korea has increased since 2009.

Development and Validation of a Mobile Application for Measuring Tibial Torsion

BACKGROUND

Tibial torsion lacks a single and reliable method for its measurement. While physical examination, computed tomography (CT), and EOS imaging are used complementarily, three-dimensional (3D) CT is the most widely used method for intuitive documentation and visualization. However, concern regarding the associated radiation hazard limits its use in the evaluation of pediatric patients. Moreover, EOS machines are too expensive and too large to be placed in every clinic requiring the measurement of tibial torsion. Therefore, a new method for 3D reconstruction is needed. In the present study, we tested the validity and reliability of a novel reconstruction tool for the lower leg.

METHODS

A statistical shape model and Laplacian constraint were adopted for the development of a new reconstruction tool for measuring tibial torsion. Tibial torsion measurements based on a 3D reconstruction application and CT images for 36 patients were evaluated for intraobserver and interobserver reliability. Tibial torsion measurements for 75 patients were compared for validation.

RESULTS

A 3D reconstruction system for the lower leg was developed as a mobile application and was installed in a portable device for easy access in the clinical setting. In terms of interobserver reliability, the intraclass correlation coefficient among 3 clinicians was 0.896 (95% confidence interval [CI], 0.828 to 0.941). The correlation coefficient between tibial torsion measured with use of 3D CT and that measured with the mobile application was 0.865 (p < 0.001).

CONCLUSIONS

The mobile application showed excellent reliability and validity for measuring tibial torsion. Concurrent utilization with mobile application for the femur allows visualization of the rotational profile of the leg without the need for CT or EOS.

LEVEL OF EVIDENCE

Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Rebound phenomenon and its risk factors after hemiepiphysiodesis using tension band plate in children with coronal angular deformity

BACKGROUND

This study was performed to evaluate the rebound phenomenon after the correction of coronal angular deformity by hemiepiphysiodesis using tension band plate in children and to identify its risk factors.

METHODS

We reviewed 50 children (mean age, 11.0 ± 2.5 years) with 94 physes who had undergone hemiepiphysiodesis using tension band plate due to coronal angular deformity of the lower limb. Patients' demographic data including sex, age at initial surgery and plate removal, affected bone (distal femur or proximal tibia), affected side, and body mass index were collected. The mechanical lateral distal femoral angle (mLDFA) and the mechanical medial proximal tibial angle (mMPTA) were measured from the teleradiogram, Physes were divided into rebound and non-rebound group, and rebound group was defined as the physes which had  ≥  5° of mLDFA or mMPTA returning to its original deformity. Generalized estimating equation based multivariable analysis was used to identify the risk factors for the rebound phenomenon after the deformity correction.

RESULTS

A total of 41 physes classified into rebound group and 53 physes into non-rebound group. There were significant differences in the age at initial surgery (p = 0.004), the age at implant removal (p = 0.002), the amount of correction (p = 0.001), and the rate of correction (p < 0.001) between two groups. The rate of correction was significantly associated with the rebound phenomenon (p = 0.044). The risk of rebound phenomenon was 1.2-fold higher as the rate of correction increased by 1° per year. The cutoff values of the correction rate between the two groups were 6.9°/year (p < 0.001).

CONCLUSIONS

This study showed that the rebound group had younger age and faster correction rate than those in the non-rebound group. In addition, the correction rate for deformity was a significant risk factor for the rebound phenomenon after hemiepiphysiodesis using the tension band plate. Close monitoring after implant removal is required for children who have a rapid correction rate over 7°/year.

Radiographic Follow-up After Normal Ultrasound Screening of the Hip in Breech Infants

BACKGROUND

Breech presentation is one of the most important risk factors for developmental dysplasia of the hip, and all breech infants should be screened. The necessity of further follow-up of developmental dysplasia of the hip after normal clinical and sonographic screening is a controversial subject. The purpose of this study to identify the incidence of delayed dysplasia in breech infants after normal ultrasound screening and the necessity of further clinical and radiologic follow-up in these patients.

METHODS

We included the 292 breech babies (128 boys and 164 girls) who showed normal hip ultrasound screening results. To determine the incidence of delayed radiographic dysplasia, anteroposterior hip radiographs were taken between 12 and 24 months of age to measure the acetabular index (AI).

RESULTS

The mean AI values were 22.8±3.4 in boys and 24.9±3.1 in girls. Applying the Tönnis criteria, 29 patients (9.9%) were considered to have delayed radiographic dysplasia (16 boys and 13 girls). No significant difference was found in any demographic variables between babies with and without delayed radiographic dysplasia. None of these 29 infants underwent any treatment for radiographic dysplasia. Applying Kuong's criteria to 292 infants, only 2 patients (0.7%) demonstrated radiographic dysplasia on the hip anteroposterior radiographs taken at 14 months.

CONCLUSIONS

The incidence of radiographic dysplasia significantly varied depending on which criteria were applied. In order to find out more accurate incidence rates of delayed radiographic dysplasia, large-scale studies of the normative AI data for Korean infants are required.

LEVEL OF EVIDENCE

Prognostic Level III.

What happens to the patella height in patients with cerebral palsy as they age

We aimed to investigate the progression of patella alta (PA) in patients with cerebral palsy (CP) using the Koshino-Sugimoto (KS) index and assess associated risk factors. Participants in our retrospective study met the following inclusion criteria: patients with CP who visited our institute from May 2003 to December 2019, were ≤18 years of age, were followed up for >2 years and had at least two lateral knee radiographs. KS indices of both knee radiographs were measured for each patient. A linear mixed model was implemented. Our participants included 222 CP patients. KS index values were measured via 652 knee radiographs. Reference values of the KS index for those between 4 and 18 years of age were determined according to Gross Motor Function Classification System (GMFCS) levels. In all GMFCS levels, the KS index decreased with patients' ages (P < 0.0001). In groups where the KS index increased, GMFCS levels IV (P = 0.0045) and V (P = 0.0040) were statistically significant. Change in the KS index values indicates that PA improves as patients age within all GMFCS levels. However, in patients with GMFCS levels of IV and V, progressive PA is expected.

Intrasubject Radiographic Progression of Hallux Valgus Deformity in Patients With and Without Metatarsus Adductus: Bilateral Asymmetric Hallux Valgus Deformity

This study was to analyze intrasubject radiographic progression of the hallux valgus deformity by comparing the mildly and severely affected sides in patients with bilateral asymmetric hallux valgus in the whole group as well as the metatarsus adductus and the nonmetatarsus adductus subgroups. A total of 186 patients with bilateral asymmetrical hallux valgus deformity with a difference of 5° or greater in the hallux valgus angle were included, and 11 radiographic measurements were analyzed. The radiographic differences between the mildly and severely affected sides were compared. Correlation between the changes in the hallux valgus angle and those in other measurements was analyzed, and multiple regression analyses were performed. The anteroposterior talo-second metatarsal angle showed no significant difference between the mildly and severely affected sides. Changes in the intermetatarsal angle and sesamoid rotation angle were significantly associated with the progression of hallux valgus angle in the whole group as well as the nonmetatarsus adductus subgroup. Change in the intermetatarsal angle (p = .006) was the significant factor associated with the progression of hallux valgus angle in the metatarsus adductus subgroup. The anteroposterior talo-second metatarsal angle might be useful in evaluating the overall foot shape in the hallux valgus deformity. Progression of the hallux valgus deformity might be pathophysiologically different between those with and without metatarsus adductus.

Usefulness of Bone SPECT/CT for Predicting Avascular Necrosis of the Femoral Head in Children with Slipped Capital Femoral Epiphysis or Femoral Neck Fracture

OBJECTIVE

This study aimed to investigate the usefulness of bone single-positron emission tomography/computed tomography (SPECT/CT) of the hip in predicting the later occurrence of avascular necrosis (AVN) after slipped capital femoral epiphysis (SCFE) or femoral neck fracture in pediatric patients. The quantitative parameters of SPECT/CT useful in predicting AVN were identified.

MATERIALS AND METHODS

Twenty-one (male:female, 10:11) consecutive patients aged < 18 years (mean age ± standard deviation [SD], 11.0 ± 2.7 years) who underwent surgery for SCFE or femoral neck fracture and postoperative bone SPECT/CT were included. The maximum standardized uptake value (SUV), mean SUV, and minimum SUV of the femoral head were measured. The ratios of the maximum SUV, mean SUV, and minimum SUV of the affected femoral head to the contralateral side were determined. Patients were followed up for > 1 year after the surgery. The SPECT/CT parameters were compared between patients who developed AVN and those who did not. The accuracy of SPECT/CT parameters for predicting AVN was assessed.

RESULTS

Six patients developed AVN. There was a significant difference in the ratio of the mean SUV among patients who developed AVN (mean ± SD, 0.8 ± 0.3) and those who did not (1.1 ± 0.2, p = 0.018). However, there were no significant differences in the ratios of the maximum and minimum SUV between the groups (all p = 0.205). For the maximum, mean, and minimum SUVs, no significant differences were observed between the groups (p = 0.519, 0.733, and 0.470, respectively). The cutoff mean SUV ratio of 0.87 yielded a 66.7% sensitivity and 93.2% specificity for predicting AVN.

CONCLUSION

Quantitative bone SPECT/CT is useful for evaluating femoral head viability in pediatric patients with SCFE or femoral neck fractures. Clinicians should consider the high possibility of later AVN development in patients with a decreased mean SUV ratio.

National Trends in Pediatric CT Scans in South Korea: A Nationwide Cohort Study

Purpose

This study evaluated the rates and annual trends of pediatric CT scans in South Korea using a nationwide population-based database.

Materials and Methods

Data regarding pediatric CT scan usage between 2012 and 2017 were retrieved from the health insurance review and assessment service. Data on the age, sex, diagnosis, and the anatomical area of involved patients were also extracted.

Results

A total of 576376 CT examinations were performed among 58527528 children aged below 18 years (9.8 scans/1000 children), and the number of CT examinations per 1000 children was noted to have increased by 23.2% from 9.0 in 2012 to 11.0 in 2017. Specifically, the number of CT examinations increased by 32.9% for the 6–12 years of age group (7.4/1000 to 9.8/1000) and by 34.0% for the 13–18 years of age group (11.4/1000 to 15.3/1000). Moreover, majority of the CT scans were limited to the head (39.1%), followed by the extremities (32.5%) and the abdomen (13.7%). Notably, the number of extremity CT scans increased by 83.6% (2.3/1000 to 4.2/1000), and its proportion as compared to other scans increased from 25.3% to 37.7%.

Conclusion

CT scans in the pediatric population increased continuously from 2012 to 2017 at an annual rate of 4.4%. Therefore, physicians should balance the benefits of CT with its potential harms from associated radiation exposure in pediatric patients.

Change of limb alignment in Korean children and adolescents with idiopathic genu valgum

There has been no study evaluating the change of limb alignment for patients with genu valgum. The purpose of this study was to investigate the change of limb alignments in children and adolescents with idiopathic genu valgum through evaluating distal femur, proximal tibia, and knee joint line.Consecutive children and adolescents, under the age of 18, with genu valgum were included. Mechanical tibiofemoral angle, mechanical lateral distal femoral angle, mechanical medial proximal tibia angle, and joint line convergence angle were measured. The rate of changes for each radiographic measurement were analyzed using a linear mixed model.A total of 1539 teleroentgenograms from 518 limbs of 273 individuals were included in this study. Linear mixed model showed that the change of limb alignment was significantly associated with age, but not associated with gender and laterality. The mechanical tibiofemoral angle was most valgus initially, decreasing until reaching its lowest value of 2.8° at 10 years old. The mechanical lateral distal femoral angle decreases from initial neutral alignment and increases in valgus continuously. The mechanical medial proximal tibia angle decreases from initial valgus and progresses to be neutral at around the age of 10. The joint line convergence angle decreases sharply from initial valgus alignment to 0° at the age of 5.Valgus alignment in children with idiopathic genu valgum decreases until approximately the age of 10. In younger children, the tibia and joint line contribute most to overall valgus alignment; in older children, the femur contributes the most. Based on our results, we recommend monitoring patient limb alignment until it stabilizes around the age of 10, and then carefully planning and performing corrective surgery with complete consideration of the changing bony alignment.

Effect of Screw Configuration on the Rate of Correction for Guided Growth Using the Tension-band Plate

BACKGROUND

This study investigated the effect of screw configuration on the rate of correction of coronal angular deformity of the knee joint in children who underwent guided growth using the tension-band plate.

METHODS

Consecutive patients (76 patients with 154 physes; mean age: 11.8±2.2 y) who underwent guided growth using the tension-band plate for coronal angular deformity (genu varum or genu valgum) were included. The mechanical lateral distal femoral angle, mechanical medial proximal tibial angle, and screw angle were measured from the teleroentgenograms of preoperative and postoperative periodic follow-up visits.

RESULTS

The mean initial screw angle and the mean rate of correction were 16.7±10.5 degrees and 6.5±5.3 degrees per year, respectively. The rate of correction was significantly affected by age at surgery, sex, physis treated, severity of deformity, and rate of change in screw angle (all P<0.001). However, the initial screw angle and type of deformity did not affect the rate of correction. The rate of correction per year was 3.6 degrees higher in boys than in girls and 2.8 degrees higher in the distal femur than in the proximal tibia. A 1 degree increase in the rate of change in screw angle was associated with a 0.5 degree increase in the correction rate. Screw angle significantly increased with follow-up duration (P<0.001) and the change in screw angle was significantly affected by age, sex, and physis treated (all P<0.001).

CONCLUSIONS

This study demonstrated that screw configuration did not affect the correction rate of coronal angular deformity for guided growth using the tension-band plate. Therefore, surgeons only need to insert the screws according to anatomic restriction, not considering the screw configuration when using the tension-band plate for guided growth in children.

LEVEL OF EVIDENCE

Prognostic level III.

Lengthening and deformity correction in vascularized fibular autograft for a patient with Ewing sarcoma

We report the case of a pediatric patient with Ewing's sarcoma of the tibia treated with vascularized fibular autograft where the resulting limb deformity and leg length discrepancy (LLD) were corrected using Ilizarov external fixator. A 14-year-old girl presented to our outpatient clinic with a deformity of the right proximal and distal tibia and an 11.7 cm of LLD after tumor reconstruction surgery. Deformity correction and limb lengthening were simultaneously performed using double corticotomy on the right proximal and distal tibia. One year postoperatively, the union of the right proximal tibia had progressed, but nonunion was observed at the right distal corticotomy site. To address this, osteosynthesis with tricortical iliac bone allograft was performed after the removal of the Ilizarov external fixator. After 6 months, the union of the distal tibia was confirmed, and the varus deformity of proximal and distal tibia improved. The LLD was also decreased, but the left lower limb was still longer by 3 cm. This report shows that vascularized fibular autografts can potentially be used for the gradual correction of LLD and deformities. However, for the treatment of multiple deformities in bones previously reconstructed with vascularized fibular graft, the possibility of impaired bone forming potential of the fibular graft should be considered.

Blood Loss and Related Laboratory Changes after Single-Event Multilevel Surgery and Hip Reconstructive Surgery in Patients with Cerebral Palsy

Backgroud

Single-event multilevel surgery (SEMLS) and hip reconstructive surgery (HRS) often cause intraoperative bleeding, consequently increasing the probability of transfusion and postoperative laboratory changes. Therefore, it is important to assess risk factors to predict the amount of blood loss. This study aimed to evaluate blood loss, its influencing factors, and the related laboratory changes during SEMLS and HRS in patients with cerebral palsy (CP).

Methods

We retrospectively examined consecutive CP patients who underwent SEMLS and HRS. Surrogate markers of blood loss, including preoperative and postoperative hemoglobin (Hb), hematocrit, and changes in Hb concentration, were assessed. Albumin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatine levels were also analyzed for related laboratory changes. Risk factors were analyzed using multiple regression and logistic regression models.

Results

The overall cohort comprised 1,188 patients. Of them, 1,007 and 181 underwent SEMLS and HRS, respectively. Furthermore, 72 of 181 patients underwent a concomitant Dega osteotomy. The regression model showed that low preoperative Hb concentration (p < 0.001), high albumin level (p = 0.007), low body mass index (BMI) (p = 0.002), and bilateral HRS (p < 0.001) were significant risk factors of postoperative anemia. Valproate medication was associated with Hb drop, and the risk factors for Hb level < 8 g/dL on postoperative day 2 were bilateral HRS and Dega osteotomy in the HRS subgroup. In total, 21.6% had elevated AST levels on postoperative day 2, and bilateral HRS (p < 0.001), Gross Motor Function Classification System (GMFCS) level V (p = 0.041), Dega osteotomy (p < 0.001), and high preoperative AST level (p < 0.001) increased the risk of AST elevation.

Conclusions

We have summarized the estimated blood loss and related laboratory changes after SEMLS and HRS in patients with CP and identified the risk factors. Clinical guidelines should be accordingly developed to include assessment of these risk factors and their impact in the outcomes of CP patients undergoing SEMLS and HRS.

Analysis of factors influencing improvement of idiopathic flatfoot

Idiopathic flatfoot is common in infants and children, and patients with this condition are frequently referred to pediatric orthopedic clinics. Flatfoot is a physiologic process, and that the arch of the foot elevates spontaneously in most children during the first decade of life. To achieve a consensus as the rate of spontaneous improvement of flatfoot, the present study aimed to estimate the rate of spontaneous improvement of flatfoot and to analyze correlating factors.We reviewed the records of patients examined between May 2013 and May 2019 so as to identify those factors associated with idiopathic flatfoot below 12 years of age. We included patients with who had been followed for >6 months, and those for whom ≥2 (anteroposterior and lateral) weight-bearing bilateral radiographs of the foot had been obtained. The progression rates of the anteroposterior (AP) talo-first metatarsal angle, talonavicular coverage angle, lateral talo-first metatarsal angle, and calcaneal pitch angle were adjusted by multiple factors using a linear mixed model, with sex, body mass index, and Achilles tendon contracture as the fixed effects and age and each subject as the random effects.We found that 4 of the radiographic measurements improved as patients grew older. The AP talo-first metatarsal angle, talonavicular coverage angle, and the lateral talo-first metatarsal angle decreased, while the calcaneal pitch angle increased. The AP talo-first metatarsal angle (P < .001), talonavicular coverage angle (P < .001), and lateral talo-first metatarsal angle (P < .001) improved significantly; however, the calcaneal pitch angle (P = .367) did not show any significant difference. In general, the flatfeet showed an improving trend; after analyzing the factors, no sex difference was observed (P = .117), while body mass index (P < .001) and Achilles tendon contracture (P < .001) showed a negative correlation.The study demonstrated that children's flatfeet spontaneously improved at the age of 12 years. It would be more beneficial if the clinician shows the predicted appearance of the foot at the completion of growth by calculating the radiographic indices and identifying the correlating factors in addition to explaining that flatfoot may gradually improve. This will prevent unnecessary medical expenses and the psychological adverse effects to the children caused by unnecessary treatment.

Evaluation of factors affecting external tibial torsion in patients with cerebral palsy

Background

Gait deviation and associated torsional problems are common in patients with cerebral palsy (CP). Although femoral anteversion in CP has been extensively reviewed in previous studies, only a few studies have focused on tibial torsion. Therefore, this study aimed to evaluate tibial torsion in patients with CP and investigate the affecting factors.

Methods

Consecutive patients with cerebral palsy who underwent 3-dimensional computed tomography for the assessment of rotational profiles were reviewed. Femoral anteversion and tibial torsion were measured, and the demographic characteristics of the patients were recorded. A linear mixed model was implemented to overcome the retrospective nature of the study.

Results

After the implementation of inclusion and exclusion criteria, 472 patients were enrolled for this study. With age, external tibial torsion increased, while femoral anteversion decreased. The factors affecting external tibial torsion were increased femoral anteversion (p = 0.0057), increased age (p < 0.0001), higher Gross Motor Function Classification System (GMFCS) level (p < 0.0001), and involved/uninvolved limbs of hemiplegia (p = 0.0471/p = 0.0047).

Conclusions

Older age, GMFCS level IV/V, hemiplegia, and increased femoral anteversion were the independent risk factors of increased external tibial torsion; therefore, performing an imaging study is recommended for assessing the extent of tibial torsion in patients with such characteristics.

Leg-length discrepancy and associated risk factors after paediatric femur shaft fracture: a multicentre study

PURPOSE

This study was performed to investigate leg-length discrepancy (LLD) and associated risk factors after paediatric femur shaft fractures.

METHODS

A total of 72 consecutive patients under 13 years old (mean age 6.7 years; 48 boys, 24 girls) with unilateral femur shaft fracture, and a minimum follow-up of 18 months, were included. The amount of LLD was calculated by subtracting the length of the uninjured from that of the injured limb. Risk factors for an LLD ≥ 1 cm and ≥ 2 cm were analyzed using multivariable logistic regression analysis.

RESULTS

Hip spica casting, titanium elastic nailing and plating were performed on 22, 40 and ten patients, respectively. The mean LLD was 7.8 mm (sd 8.8) and 29 (40.3%) had a LLD of ≥ 1 cm, while nine (12.5%) had a LLD of ≥ 2 cm. There were significant differences in fracture stability (p = 0.005) and treatment methods (p = 0.011) between patients with LLD < 1 cm and ≥ 1 cm. There were significant differences in fracture site shortening (p < 0.001) and LLD (p < 0.001) between patients with length-stable and length-unstable fractures. Fracture stability was the only factor associated with LLD ≥ 1 cm (odds ratio of 4.0; p = 0.020) in the multivariable analysis.

CONCLUSION

This study demonstrated that fracture stability was significantly associated with LLD after paediatric femur shaft fractures. Therefore, the surgeon should consider the possibility of LLD after length-stable femur shaft fracture in children.

LEVEL OF EVIDENCE

Prognostic level III.

Comparison of Bone Mineral Density and Markers of Bone Turnover in Osteoporotic Women after 6-Month Treatment with Alendronate or Bazedoxifene: A Randomized Controlled Trial

Background

In a randomized controlled trial, we compared the bone mineral densities (BMDs) and blood markers of bone turnover during short-term treatment of osteoporotic women with bisphosphonate alendronate or bazedoxifene, a selective estrogen receptor modulator.

Methods

Ten and eleven patients were randomized to the alendronate and bazedoxifene groups, respectively. BMDs were measured before and after 6 months of treatment. Blood tests were used to measure the levels of osteocalcin (OC), C-terminal telopeptide of type I collagen (CTX), vitamin D3, and parathyroid hormone pretreatment and after 3 and 6 months of treatment. The variables were compared statistically.

Results

The alendronate group showed decreases in blood levels of both OC and CTX during the study period (P<0.001 and P=0.002, respectively), while the bazedoxifene group had a decrease only in OC levels (P=0.012). After 6 months of treatment, BMDs significantly increased in the alendronate group at multiple bone sites, including the L1–4 lumbar vertebrae, femur trochanter, and total femur. However, there was no significant increase in BMD in the bazedoxifene group. BMDs were not significantly different between the 2 groups.

Conclusions

Patients treated with alendronate showed more rapid suppression of markers of bone turnover and higher BMD than those treated with bazedoxifene during a short-term regime. Considering the effects and complications of each medication, the relationship between bone turnover rate and bone quality will need to be investigated in future studies.

Consistency and Reliability of Ankle Stress Radiography in Patients With Chronic Lateral Ankle Instability

Background:

Ankle stress radiographs are important tools for evaluating chronic lateral ankle instability. The consistency of a patient’s ankle condition as it affects the reliability of ankle stress radiographs has never been evaluated.

Purpose:

To investigate the consistency and reliability of ankle stress radiographs in patients with chronic lateral ankle instability without an ankle injury during the study period.

Study Design:

Cohort study (diagnosis); Level of evidence, 3.

Methods:

Included were patients with chronic lateral ankle instability who underwent 2 repeated ankle stress radiographs between January 2014 and July 2019; those with an ankle injury during the study period were excluded. The tibiotalar tilt angle on varus stress radiographs and anterior translation of the talus on anterior drawer stress radiographs were measured at initial presentation and final follow-up examination. Interobserver reliability and consistency of ankle stress radiographs were analyzed using the intraclass correlation coefficient (ICC).

Results:

A total of 45 patients (mean ± standard deviation age, 36.4 ± 13.4 years; 18 men and 27 women; follow-up duration, 9.1 ± 3.2 months) were included. The mean ± standard deviation tibiotalar tilt angle and anterior talar translation at initial presentation were 10.8° ± 5.2° and 6.9 ± 2.7 mm, respectively. The interobserver reliabilities of the tibiotalar tilt angle and anterior talar translation were excellent (ICC = 0.926 [95% CI, 0.874-0.959] and 0.911 [95% CI, 0.766-0.961], respectively). The consistency between the initial and final radiographs was good for tibiotalar tilt angle (ICC = 0.763 [95% CI, 0.607-0.862]) and poor for anterior talar translation (ICC = 0.456 [95% CI, 0.187-0.660]).

Conclusion:

Although the interobserver reliability of the radiographic measurements was excellent, the consistency of the ankle stress radiographs was not as acceptable. Surgeons need to be cautious when deciding whether to operate on a patient with chronic lateral ankle instability based on a single ankle stress radiograph.

Can gait kinetic data predict femoral bone mineral density in elderly men and women aged 50 years and older?

This retrospective study was conducted to investigate the correlation between kinetic gait parameters and femoral bone mineral density (BMD) in elderly subjects aged 50 years and older that could walk independently. Four hundred and twenty-six subjects (158 men and 258 women; mean age 68.7 years, standard deviation (SD) 7.9 years) were included in the study. BMDs (g/cm²) of the femoral neck, trochanter, shaft, and total proximal femur were collected. Kinetic data including maximum hip power and hip power-time integral was obtained from a three-dimensional gait analysis with self-selected walking speed. Correlation between BMDs of proximal femur and gait kinetic data was analyzed. Multiple regression analysis was also performed to identify factors significantly associated with BMD. Correlation between BMD and hip kinetic data was not prominent in elderly men. In women, BMD was significantly correlated with hip kinetic data. Hip power-time integral showed greater correlation with BMD than maximum hip power during gait in elderly women. Age (p < 0.001), weight (p = 0.007) and hip power-time integral (p = 0.008) were significant factors associated with femoral neck BMD, and these factors explained 25.4% of femoral neck BMD. In conclusion, the association between the mechanical load and BMD in the different sexes provokes future research into these issues. The effects of various types of exercises on BMD should be investigated more precisely using a gait analysis tool.

Growth arrest and its risk factors after physeal fracture of the distal tibia in children and adolescents

BACKGROUND

. This study performed to investigate the incidence of growth arrest such as leg length discrepancy (LLD) and ankle joint angular deformity and its risk factors after physeal fracture of the distal tibia in children and adolescents.

MATERIALS AND METHODS

. Consecutive 78 patients (mean age 11.4 ± 2.0 years; mean follow-up period 2.0 ± 1.2 years) treated for the distal tibia physeal fracture were included. All patients underwent preoperative ankle radiographs, three-dimensional computed tomography (CT) scans, and postoperative follow-up teleradiogram. Patients were divided into two groups according to the LLD and the difference of lateral distal tibial angle (LDTA) with the contralateral limb as follows: Group 1 (growth arrest), patients with LLD ≥ 1cm or difference of LDTA ≥ 5°; Group 2 (normal growth), patients with LLD < 1cm and difference of LDTA < 5°.

RESULTS

. The overall incidence of growth arrest was 12.8% (10 of 78). The mean displacement measured using CT scan was 4.4 ± 3.2 mm (range, 0.8-14.9). Of the total 78 fractures, 65 were treated surgically and 13 fractures were treated conservatively. The initial fracture displacement was significantly different between the two groups (p<0.001). However, there were no statistically significant differences between the two groups with respect to other factors. Initial displacement was the only significant risk factor for growth arrest (p<0.003). The cutoff values of initial displacement between the two groups were 5.2mm.

CONCLUSIONS

. This study showed that degree of initial displacement was the only significant risk factor for growth arrest after physeal fracture of the distal tibia in children and adolescents. Therefore, physicians should consider the possibility of growth arrest for patients with severely displaced physeal fractures of the distal tibia.

Leg length discrepancy, overgrowth, and associated risk factors after a pediatric tibial shaft fracture

Background

This study was performed to investigate leg length discrepancy (LLD), overgrowth, and associated risk factors after pediatric tibial shaft fractures.

Materials and methods

This study included 103 patients younger than 14 years of age (mean age 7.1 years; 75 boys, 28 girls) with unilateral tibial shaft fracture and a minimum follow-up of 24 months. LLD was calculated as the difference between the lengths of the injured and uninjured limbs. Overgrowth was calculated by adding the fracture site shortening from the LLD. Risk factors were assessed in patients with LLD < 1 cm and ≥ 1 cm and overgrowth < 1 cm and ≥ 1 cm.

Results

Casting and titanium elastic nailing (TEN) were performed on 64 and 39 patients, respectively. The mean LLD and overgrowth were 5.6 and 6.4 mm, respectively. There were significant differences in sex (p = 0.018), age (p = 0.041), fibular involvement (p = 0.005), injury mechanism (p = 0.006), and treatment methods (p < 0.001) between patients with LLDs < 1 cm and ≥ 1 cm. There were significant differences in sex (p = 0.029), fibular involvement (p = 0.002), injury mechanism (p = 0.008), and treatment methods (p < 0.001) between patients with overgrowth < 1 cm and ≥ 1 cm. Sex and treatment methods were risk factors associated with LLD ≥ 1 cm and overgrowth ≥ 1 cm following pediatric tibial shaft fracture. The boys had a 7.4-fold higher risk of LLD ≥ 1 cm and 5.4-fold higher risk of overgrowth ≥ 1 cm than the girls. Patients who underwent TEN had a 4.3-fold higher risk of LLD ≥ 1 cm and 4.8-fold higher risk of overgrowth ≥ 1 cm than those treated by casting.

Conclusions

Patients undergoing TEN showed greater LLD and overgrowth than those undergoing casting, with boys showing greater LLD and overgrowth than girls. Surgeons should consider the possibility of LLD and overgrowth after pediatric tibial shaft fractures, especially when performing TEN for boys.

Level of evidence

Level III

Genu varum deformity due to premature epiphyseal closure after treatment with isotretinoin for neuroblastoma: A case report

Isotretinoin, a vitamin A derivative, is known to induce premature epiphyseal closure. We report the case of a 9-year-old boy with neuroblastoma who demonstrated premature epiphyseal closure after 1 year of isotretinoin treatment (72.3 mg/m²/day). A bone bridge developed on the bilateral proximal tibial growth plate resulting in genu varum. We performed hemiepiphysiodesis on the bilateral proximal tibia in anticipation of the spontaneous resolution of the bone bridge. Genu varum on the left side was corrected with the resolution of bone bridge. For the remaining bone bridge on the right side, arthroscopy-assisted physeal bar resection was performed, and genu varum on the right lower extremity was also corrected. A regular review of the alignment of the upper and lower limbs is necessary to provide timely intervention in patients using isotretinoin, considering the possibility of premature epiphyseal closure.

Changes in the bony alignment of the foot after tendo-Achilles lengthening in patients with planovalgus deformity

Background

This study was performed to investigate the change in the bony alignment of the foot after tendo-Achilles lengthening (TAL) and the factors that affect these changes in patients with planovalgus foot deformity.

Methods

Consecutive 97 patients (150 feet; mean age 10 years; range 5.1–35.7) with Achilles tendon contracture (ATC) and planovalgus foot deformity who underwent TAL were included. All patients underwent preoperative and postoperative weight-bearing anteroposterior (AP) or lateral (LAT) foot radiographics. Changes in AP talo-1st metatarsal angle, AP talo-2nd metatarsal angle, LAT talo-1st metatarsal angle, and calcaneal pitch angle and the factors affecting such changes after TAL were analyzed using lineal mixed model.

Results

There were no significant change in AP talo-1st metatarsal angle and AP talo-2nd metatarsal angle after TAL in patients with cerebral palsy (CP) (p = 0.236 and 0.212). However, LAT talo-1st metatarsal angle and calcaneal pitch angle were significantly improved after TAL (13.0°, p < 0.001 and 4.5°, p < 0.001). Age was significantly associated with the change in LAT talo-1st metatarsal angle after TAL (p = 0.028). The changes in AP talo-1st metatarsal angle, AP talo-2nd metatarsal angle, and calcaneal pitch angle after TAL were not significantly associated with the diagnosis (p = 0.879, 0.903, and 0.056). However, patients with CP showed more improvement in LAT talo-1st metatarsal angle (− 5.0°, p = 0.034) than those with idiopathic cause.

Conclusion

This study showed that TAL can improve the bony alignment of the foot in patients with planovalgus and ATC. We recommend that physicians should consider this study’s findings when planning operative treatment for such patients.

Remodelling of femoral head deformity after hip reconstructive surgery in patients with cerebral palsy

Aims

Hip displacement, common in patients with cerebral palsy (CP), causes pain and hinders adequate care. Hip reconstructive surgery (HRS) is performed to treat hip displacement; however, only a few studies have quantitatively assessed femoral head sphericity after HRS. The aim of this study was to quantitatively assess improvement in hip sphericity after HRS in patients with CP.

Methods

We retrospectively analyzed hip radiographs of patients who had undergone HRS because of CP-associated hip displacement. The pre- and postoperative migration percentage (MP), femoral neck-shaft angle (NSA), and sphericity, as determined by the Mose hip ratio (MHR), age at surgery, Gross Motor Function Classification System level, surgical history including Dega pelvic osteotomy, and triradiate cartilage status were studied. Regression analyses using linear mixed model were performed to identify factors affecting hip sphericity improvement.

Results

A total of 108 patients were enrolled. The mean preoperative MP was 58.3% (SD 31.7%), which improved to 9.1% (SD 15.6%) at the last follow-up. NSA and MHR improved from 156.5° (SD 11.5°) and 82.3% (SD 8.6%) to 126.0° (SD 18.5°) and 89.1% (SD 9.0%), respectively. Factors affecting the postoperative MHR were preoperative MP (p = 0.005), immediate postoperative MP (p = 0.032), and history of Dega osteotomy (p = 0.046).

Conclusion

We found that hip sphericity improves with HRS. Preoperative MP, reduction quality, and acetabular coverage influence femoral head remodelling. We recommend that surgeons should consider intervention early before hip displacement progresses and that during HRS, definite reduction and coverage of the femoral head should be obtained.

Cite this article: Bone Joint J 2021;103-B(1):198–203.

Patients’ perspectives on the conventional synthetic cast vs a newly developed open cast for ankle sprains

BACKGROUND

Orthopedic physicians typically apply a cast to immobilize a body part that has been injured. There have been no significant structural changes or advances in synthetic casts since the development of the modern cast. The Opencast^® is a recently developed type of cast that allows ventilation and direct visual inspection of the skin to avoid cast-related complications. Although this novel cast appears to have more benefits than the conventional synthetic cast, its clinical efficacy and advantages have not been established.

AIM

To investigate the clinical efficacy and advantages of the newly developed Opencast^® based on patients’ perspectives in those with ankle inversion injury.

METHODS

A specifically designed questionnaire consisting of 19 items was used to compare patients’ opinions and concerns of the Opencast^® and the conventional synthetic cast. The items were focused on subjective patient satisfaction, discomfort, and adverse effects while wearing the cast. Patients with an ankle inversion injury diagnosed as a high-grade ankle sprain were enrolled. The subjects were randomized and instructed to fill the questionnaire after wearing a synthetic cast or an Opencast^® for 2 wk. They were then required to fill the questionnaire again, after switching to the alternative type of cast for 2 more weeks.

RESULTS

A total of 22 subjects participated in the study. The synthetic cast appeared to be more rigid and stable than the Opencast^®, but there was no significant difference in the amount of pain relief. The likelihood of adverse effects when wearing the synthetic cast was significantly higher. Patient satisfaction tended to be rated higher after wearing the Opencast^®. Opencast^® showed more subjective vulnerability than the synthetic cast, but there was no significant difference in the redo rate. Patients were more anxious about removal of the synthetic cast than of the Opencast^®.

CONCLUSION

The results indicate that the Opencast^® could replace the conventional synthetic cast as it offers increased patient satisfaction, which would in turn increase compliance to treatment.

Shielding effect of radiation dose reduction fiber during the use of C-arm fluoroscopy: a phantom study

This study evaluated the shielding effect of a newly developed dose-reduction fiber (DRF) made from barium sulfate, in terms of radiation doses delivered to patients' radiosensitive organs and operator during C-arm fluoroscopy and its impact on the quality of images. A C-arm fluoroscopy unit was placed beside a whole-body phantom. Radiophotoluminescent glass dosimeters were attached to the back and front of the whole-body phantom at 20 cm intervals. Radiation doses were measured without DRF and with it applied to the back (position 1), front (position 2) or both sides (position 3) of the phantom. To investigate the impact of DRF on the quality of fluoroscopic images, step-wedge and modulation transfer function phantoms were used. The absorbed radiation doses to the back of the phantom significantly decreased by 25.3-88.8% after applying DRF to positions 1 and 3. The absorbed radiation doses to the front of the phantom significantly decreased by 55.3-93.6% after applying DRF to positions 2 and 3. The contrast resolution values for each adjacent step area fell in the range 0.0119-0.0209, 0.0128-0.0271, 0.0135-0.0339 and 0.0152-0.0339 without and with DRF applied to positions 1, 2 and 3, respectively. The investigated DRF effectively reduces absorbed radiation doses to patients and operators without decreasing the quality of C-arm fluoroscopic images. Therefore, routine clinical use of the DRF is recommended during the use of C-arm fluoroscopy.

Factors Affecting Subjective Symptoms in Children with Pes Planovalgus Deformity: A Study Using the Oxford Ankle Foot Questionnaire

BACKGROUND

Idiopathic pes planovalgus is one of the most common foot deformities in children and adolescents. However, there is a discrepancy between subjective symptoms and radiographic severity in idiopathic planovalgus deformity, and very few studies have investigated this aspect. Further, the assessment of subjective symptoms in patients with pes planovalgus requires a quantitative scoring system for making meaningful comparisons, such as the Oxford Ankle Foot Questionnaire for Children (OxAFQ-c) and that for parents (OxAFQ-p). Therefore, the purpose of this study was to evaluate the factors affecting the symptoms of idiopathic planovalgus using the OxAFQ.

METHODS

All patients who were ≤18 years of age, had visited our clinic for the evaluation of pes planovalgus deformity, and had completed the OxAFQ were included in this study. The anteroposterior talo-first metatarsal, lateral talo-first metatarsal, and hallux valgus angles were measured on weight-bearing radiographs. The data were analyzed using a multiple regression model, with age, sex, and radiographic indices as explanatory variables.

RESULTS

Overall, 123 patients were enrolled in this study, and 246 standing foot radiographs were evaluated along with scores in each domain of the OxAFQ. The factors affecting physical domain scores in the OxAFQ-c were female sex (p = 0.047) and the anteroposterior talo-first metatarsal angle (p = 0.033). Age of ≥10 years was a significant factor (p < 0.05) affecting all domains in both the OxAFQ-c and OxAFQ-p other than the physical domain score.

CONCLUSIONS

Although pes planovalgus deformity is 3-dimensional, the forefoot abduction component of the deformity should be carefully assessed as it is closely related to subjective symptoms. Further, in female patients with a more severe anteroposterior talo-first metatarsal angle, an aggravation of symptoms with aging should be expected when managing pes planovalgus deformity.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Differences in responses to English and Korean versions of the Caregiver Priorities & Child Health Index of Life with Disabilities (CPCHILD)

Background

The purpose of this study was to identify differences in caregiver responses to Korean-language and English-language versions of the Caregiver Priorities & Child Health Index of Life with Disabilities (CPCHILD) questionnaire.

Methods

Patient data were acquired from the Cerebral Palsy Hip Outcomes Project database, which was established to run a large international multicenter prospective cohort study of the outcomes of hip interventions in cerebral palsy. Thirty-three children whose caregivers had completed the Korean version of CPCHILD were matched by propensity scoring with 33 children whose parents completed the English version. Matching was performed on the basis of 12 covariates: age, gender, gross motor function classification system level, migration percentage of right and hip, seizure status, feeding method, tracheostomy status, pelvic obliquity, spinal deformity, parental report of hip pain and contracture interfering with care.

Results

There were no significant differences in CPCHILD scores for section 4 (Communication and Social Interaction), and section 5 (Health) between two groups. Korean-language CPCHILD scores were significantly lower than English-language CPCHILD scores for section 1 (Personal Care/Activities of Daily Living), section 2 (Positioning, Transferring and Mobility), section 3 (Comfort and Emotions) and section 6 (Overall Quality of Life) as well as in terms of total score.

Conclusions

Cultural influences, and the community or social environment may impact the caregivers’ perception of the health-related quality of life of their children. Therefore, physicians should consider these differences when interpreting the study outcomes across different countries.

Transcultural adaptation and validation of a Korean version of the Oxford Ankle Foot Questionnaire for children

BACKGROUND

The purpose of this study was to translate and transculturally adapt the original English version of the Oxford Ankle Foot Questionnaire (OAFQ) into a Korean version, and to evaluate its psychometric properties.

METHODS

A Korean OAFQ for children was developed according to established guidelines. To test validity, 169 consecutive patients with foot and ankle problems and their caregivers each completed the OAFQ. The children also completed a Korean version of the KIDSCREEN-52 health related quality of life questionnaire (KIDSCREEN-52 HRQOL). To validate the Korean version of the OAFQ, reliability (child-parent agreement and internal consistency), feasibility (floor and ceiling effects), and construct validity were evaluated, and factor analysis was performed.

RESULTS

In terms of reliability, Cronbach's α values were > 0.7 in all subscales of the OAFQ (0.765 to 0.901). Child-parent agreement was confirmed by high intraclass correlation coefficients for all subscales (0.791 to 0.863). In terms of construct validity, there were moderate correlations between the subscales of the OAFQ and the subscales of the KIDSCREEN-52 HRQOL. Factor analysis revealed a three-component solution for both the child/adolescent and parent-proxy version, by combining the school and play, and footwear items into one subscale. In terms of feasibility, no floor effects were found for all subscales. However, ceiling effects were observed for the school and play, and emotional subscales for child/adolescent and parent-proxy versions.

CONCLUSIONS

The OAFQ was successfully translated and transculturally adapted into the Korean language; the Korean version of the OAFQ represents a reliable and valid instrument for evaluating children's foot or ankle problems. However, factor analysis suggested the use of a three-subscale questionnaire.

Discrepancy between true ankle dorsiflexion and gait kinematics and its association with severity of planovalgus foot deformity

Background

In planovalgus deformity with triceps contracture, a midfoot break happens, and ankle dorsiflexion (ADF) occurs at the mid-tarsal joint during gait. Results of standard 3D gait analysis may misinterpret the true ankle dorsiflexion because it recognizes the entire foot as a single rigid segment. We performed this study to investigate whether the severity of planovalgus deformity is associated with the discrepancy between the value of ADF evaluated by physical examination and 3-dimensional (3D) gait analysis. In addition, we aimed to identify the radiographic parameters associated with this discrepancy and their relationships.

Methods

Consecutive 40 patients with 65 limbs (mean age, 11.7 ± 5.5 years) with planovalgus foot deformity and triceps surae contracture were included. All patients underwent 3D gait analysis, and weightbearing anteroposterior (AP) and lateral (LAT) foot radiographs. ADF with knee extension was measured using a goniometer with the patient’s foot in an inverted position.

Results

Twenty-one limbs underwent operation for planovalgus foot deformity, and 56 limbs underwent operation for equinus deformity. The difference between ADF on physical examination and ADF at initial contact on gait analysis was 17.5 ± 8.4°. Differences between ADF on physical examination and ADF at initial contact on gait analysis were significantly associated with the LAT talus-first metatarsal angle (p = 0.008) and calcaneal pitch angle (p = 0.006), but not associated with the AP talus-first metatarsal angle (p = 0.113), talonavicular coverage angle (p = 0.190), talocalcaneal angle (p = 0.946), and naviculocuboid overlap (p = 0.136).

Conclusion

The discrepancy between ADF on physical examination and 3D gait analysis was associated with the severity of planovalgus deformity, which was evaluated on weightbearing LAT foot radiographs. Therefore, physicians should be cautious about interpreting results from 3D gait analysis and perform a careful physical examination to assess the degree of equinus deformity in patients with planovalgus foot deformity.

Progression of planovalgus deformity in patients with cerebral palsy

BACKGROUND

Analyzing radiographic changes of pes planovalgus(PV) deformity of cerebral palsy(CP) patients according to age and influencing factors.

METHODS

CP patients with PV deformity younger than 18 years old who had undergone more than a year of follow-up with at least two standing foot radiographs were included. Anteroposterior and lateral talo-first metatarsal(talo-1stMT), talo-second metatarsal(talo-2ndMT), and hallux valgus(HV) angles were measured on the radiographs. The rate of progression was adjusted by multiple factors using the linear mixed model, with the Gross Motor Function Classification System(GMFCS) level as the fixed effect and age and each subject as random effects.

RESULTS

Overall, 194 patients were enrolled in this study, and 1272 standing foot radiographs were evaluated. The AP talo-2^ndMT angle progressed by 0.59° (p < 0.0001) and 0.64° (p = 0.0007) in GMFCS level II and III patients, respectively; however, there was no significant change in GMFCS level I patients (p = 0.3269). HV was significantly affected by age in all three GMFCS groups; it increased by 0.48° (p < 0.0001), 0.66° (p < 0.0001), and 1.19° (p < 0.0001) for levels I, II, and III, respectively. The lateral talo-1stMT angle showed improvements in GMFCS level I and II patients (0.43°, p < 0.0001, and 0.61°, p < 0.0001, respectively). In GMFCS level III patients, there was no significant improvement in the lateral talo-1^stMT angle (p = 0.0535).

CONCLUSIONS

The GMFCS level was the single most important factor influencing the progression of radiographic indices in PV deformity in CP. The AP talo-1^stMT and talo-2ndMT angles progressed in patients with GMFCS levels II and III. Physicians should take this result into consideration when planning the timing of the surgery.

LEVEL OF EVIDENCE

Prognostic Level IV.

Surgical outcomes after single event multilevel surgery in cerebral palsy patients with mid-stance knee hyperextension

BACKGROUND

Some patients with cerebral palsy (CP) exhibit excessive knee flexion at initial contact followed by knee hyperextension (KE) in mid-stance.

RESEARCH QUESTION

This study investigated the change in sagittal kinematics after distal hamstring lengthening (DHL) and triceps surae lengthening procedures in CP patients with KE, and compared it to those without KE. In addition, the risk factors for the worsening of postoperative KE were analyzed.

METHODS

Consecutive 312 patients (596 limbs) with CP who underwent DHL and triceps surae lengthening were included. All patients underwent preoperative and 1-year postoperative three-dimensional gait analysis. Patients' limbs were divided into the KE and knee flexion (KF) groups, according to preoperative minimum knee flexion in stance. KE was defined as minimum knee flexion in stance less than 0°.

RESULTS

The KE and KF groups included 130 and 466 limbs, respectively. Knee and ankle sagittal kinematics significantly improved after surgery in both groups. Minimum knee flexion in stance significantly increased from -6.6˚ to 0.5˚ in the KE group, but decreased from 14.6˚ to 7.8˚ in the KF group. Among the KE group, minimum knee flexion in stance improved in 103 limbs (79.2 %), but worsened in 27 limbs (20.8 %). Degree of preoperative KE was the only factor significantly associated with postoperative worsening of KE (p=0.002). The cutoff value for the worsening of KE was -5.8˚ of preoperative minimum knee flexion in stance.

SIGNIFICANCE

This study demonstrated that the sagittal kinematics of the knee and ankle joints improved after DHL and triceps surae lengthening procedures in CP patients with and without KE. Preoperative degree of KE was a risk factor for the worsening of KE after surgery. Therefore, careful selection for indication of DHL is required to prevent postoperative KE due to overlengthening of the hamstrings, particularly in patients with severe preoperative KE.

Correlation between Accelerometer and Questionnaire-Based Assessment of Physical Activity in Patients with Cerebral Palsy

Background

Precise measuring and monitoring of physical activity (PA) in patients with cerebral palsy (CP) are critical for assessing their PA participation and its potential health benefits. Accelerometer-based assessment of PA has been considered valid, reliable, and practical in children with CP. Therefore, we investigated the correlation between accelerometer- and questionnaire-based assessment of PA in CP patients.

Methods

Nineteen patients with CP who were classified as Gross Motor Function Classification System level I–III and 84 normally developed participants were included in the study. Study participants wore an accelerometer for seven days, after which they visited the hospital and completed the International Physical Activity Questionnaire (IPAQ). CP patients and their caregivers completed the Pediatric Outcomes Data Collection Instrument (PODCI) and the Caregiver Priorities and Child Health Index of Life with Disabilities, respectively. The concurrent validity of the questionnaires was assessed.

Results

In the accelerometer-based assessment, time spent in PA was significantly shorter at every intensity level in CP patients than in normally developed participants. However, PA assessed by the IPAQ was significantly higher in patients with CP, indicating that they tend to exaggerate their participation in PA. On the correlation of the assessment by the accelerometer and by the PODCI, transfer/basic mobility, sports/physical function, and happiness increased significantly as the number of steps taken and the distance travelled increased.

Conclusions

In patients with CP, happiness and quality of life are associated with higher levels of PA. Thus, programs for patients with CP should focus on improving their PA.

Radiographic changes of the mid-tarsal joint after calcaneal lengthening for planovalgus foot deformity

BACKGROUND

This study evaluate the radiographic changes in the mid-tarsal joint, including the calcaneocuboid and talonavicular (TN) joints after calcaneal lengthening for planovalgus deformity in children.

METHODS

This study included 38 patients (68 feet) who underwent calcaneal lengthening for planovalgus deformity. Radiographic osteoarthritic changes at the CC or TN joint were defined as modified Kellgren-Lawrence grade of ≥1.

RESULTS

Among the 68 feet, 31 feet (45.6%) showed radiographic osteoarthritic changes at the CC joint and 20 (29.4%) showed changes at the TN joint. Risk of radiographic osteoarthritic changes at the CC joint was associated with increased age at surgery (OR = 1.2, p = 0.038). Risk of radiographic osteoarthritic changes at the TN joint was associated with increased age at surgery (OR = 2.2; p = 0.002), preoperative AP talus-1st metatarsal angle (OR = 1.1; p = 0.044), and degree of CC subluxation (OR = 2.1; p = 0.007).

CONCLUSIONS

Surgeons should consider the risk factors in the surgical correction of planovalgus deformity to prevent mid-tarsal arthritis.

Cluster of Lymphadenitis due to Nontuberculous Mycobacterium in Children and Adolescents 8-15 Years of Age

BACKGROUND

Nontuberculous mycobacteria (NTM) lymphadenitis is an under-recognized entity, and data of the true burden in children are limited. Without a high index of suspicion, diagnosis may be delayed and microbiological detection is challenging. Here, we report a cluster of NTM lymphadenitis experienced in Korean children.

METHODS

Subjects under 19 years of age diagnosed with NTM lymphadenitis during November 2016-April 2017 and April 2018 were included. Electronic medical records were reviewed for clinical, laboratory and pathological findings. Information regarding underlying health conditions and environmental exposure factors was obtained through interview and questionnaires.

RESULTS

A total of ten subjects were diagnosed during 18 months. All subjects were 8-15 years of age, previously healthy, male and had unilateral, nontender, cervicofacial lymphadenitis for more than 3 weeks with no significant systemic symptoms and no response to empirical antibiotics. Lymph nodes involved were submandibular (n = 8), preauricular (n = 6) and submental (n = 1). Five patients had two infected nodes and violaceous discoloration was seen in seven subjects. Biopsy specimens revealed chronic granulomatous inflammation and acid-fast bacteria culture identified Mycobacterium haemophilum in two cases and NTM polymerase chain reaction was positive in two cases. Survey revealed various common exposure sources.

CONCLUSION

NTM lymphadenitis is rare but increasing in detection and it may occur in children and adolescents. Diagnosis requires high index of suspicion and communication between clinicians and the laboratory is essential for identification of NTM.

Inverse Relationship Between Radiographic Lateral Ankle Instability and Osteochondral Lesions of the Talus in Patients With Ankle Inversion Injuries

BACKGROUND

Insufficient or excessive bony constraint surrounding the talus might contribute to the occurrence of ligamentous injury or bone contusion, respectively, at the time of ankle inversion injuries. This study aimed to investigate the relationship between radiographic lateral ankle instability and osteochondral lesions of the talus (OLT) following ankle inversion injuries.

METHODS

A total of 195 patients (113 men and 83 women; mean age, 38.7 years) with a history of ankle inversion injuries were included in this study. All patients underwent ankle magnetic resonance imaging (MRI) and stress radiography. The tibiotalar tilt angle on varus stress radiograph, anterior translation of the talus on anterior-drawer lateral radiographs, bimalleolar tilt angle, and fibular position were radiographically determined. The radiographic lateral ankle instability was defined as tibiotalar tilt angle ≥10 degrees, and the presence of OLT was confirmed on MR images. The relationship between the radiographic lateral ankle instability and the presence of OLT was statistically analyzed.

RESULTS

The presence of radiographic lateral ankle instability (tibiotalar tilt angle ≥10 degrees) showed an inverse relationship with that of OLT in the chi-squared test (P = .003). An increased tibiotalar tilt angle was associated with lower incidence of OLT (P = .011) in the multiple regression analysis, and the presence of OLT was associated with a decreased tibiotalar tilt angle (P = .016) in the binary logistic regression analysis.

CONCLUSIONS

This study showed an inverse relationship between lateral ankle instability and the development of OLT following ankle inversion injury. The role of bony constraint in the development of sports injuries in the ankle should be considered with these injuries.

LEVEL OF EVIDENCE

Level III, diagnostic, comparative study.

Effects of soft tissue surgery on transverse kinematics in patients with cerebral palsy

Background

Gait disturbances, including flexed knee gait, stiff knee gait, and tip-toeing gait, are common in patients with cerebral palsy (CP). There has been no reports regarding kinematic changes in the transverse plane after soft tissue surgeries, such as distal hamstring lengthening (DHL), rectus femoris transfer (RFT), and tendo-Achilles lengthening (TAL). This study aimed to evaluate changes in the transverse plane after soft tissue surgery in patients with CP by assessing the effects of the DHL, RFT, and TAL.

Methods

The study enrolled 156 consecutive patients (mean age, 8.4 years; range, 4.4 to 20.9), representing 213 operated limbs, who underwent soft tissue surgery including DHL with semitendinosus transfer, RFT, and TAL. All patients were assessed by preoperative and 1-year postoperative three-dimensional gait analysis. Changes in transverse plane kinematics after soft tissue surgery and affecting factors were analyzed.

Results

Sagittal kinematics including knee flexion at initial contact, ankle dorsiflexion at initial contact, and mean ankle dorsiflexion in the stance phase were significantly improved after single event multilevel surgery (all p < 0.001). Transverse kinematics, including mean tibial rotation and foot progression angle, were significantly improved to a more external angle after soft tissue surgeries (− 2.9°, p = 0.004 and − 9.5°, p < 0.001). The mean hip rotation was significantly improved to a more external angle by RFT (− 4.7°, p = 0.010) and the foot progression angle was significantly improved to a more external angle by TAL (− 3.9°, p = 0.028).

Conclusions

This study found that the transverse kinematics were improved to a more external angle after soft tissue surgery in patients with CP. Therefore, clinicians should consider that soft tissue surgery can affect the transverse plane kinematics in patients with CP. To confirm our findings, further research regarding the natural history of femoral and tibial torsion in children with CP is needed.

Natural progression of radiographic indices in juvenile hallux valgus deformity

BACKGROUND

This study aimed to estimate the annual change in radiographic indices for juvenile hallux valgus (JHV) and to analyze the factors that influence deformity progression.

METHODS

Patients aged <15 years who had JHV and were followed up for at least 1 year were included. Hallux valgus angle (HVA), hallux interphalangeal angle, intermetatarsal angle, metatarsus adductus angle, distal metatarsal articular angle, anteroposterior talo-first metatarsal angle, and lateral talo-first metatarsal angle were evaluated. The progression rate of HVA was adjusted by multiple factors by using a linear mixed model.

RESULTS

A total of 133 feet were included. The HVA and distal metatarsal articular angle both increased by 0.8° per year (p<0.001 and p=0.003, respectively). HVA increased by 1.5° per year (p<0.001) at under the age of 10, and the HVA progression in the older patients was not statistically significant.

CONCLUSIONS

JHV deformity could progress with aging. Most deformity progression could occur before the age of 10 years.

Short-Term Outcomes and Influencing Factors After Ankle Fracture Surgery

The present study investigated the factors influencing the early clinical outcomes after ankle fracture surgery. We included 88 patients, who had undergone implant removal surgery at 1 year after ankle fracture surgery, with ankle computed tomographic (CT) scans obtained before ankle fracture surgery and at implant removal available. We collected demographic information, including age, sex, the presence of diabetes mellitus, level of trauma energy, and fracture classification from the medical records. We also recorded the fracture height using the radiographs and CT images. The medial joint space and articular incongruity were assessed on the follow-up radiographs and CT scans. Bone attenuation was measured by placing a circular region of interest around the ankle joint on the preoperative CT image. The postimplant removal outcomes were assessed using 2 functional questionnaires, the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale and Foot and Ankle Outcome Score (FAOS). Significant factors related to the AOFAS ankle-hindfoot scale scores and FAOS were identified through univariate analysis using age, sex, radiographic measurements, and CT findings as explanatory variables, followed by multiple regression analysis. On multiple regression analysis, the total FAOS was independently related to the AO classification (p = .003) and Lauge-Hansen classification (p = .003). The total AOFAS ankle-hindfoot scale score was related to articular incongruity (p = .044). The early clinical outcomes after ankle fracture surgery were affected by involvement of the ankle joint fracture rather than the lateral malleolus fracture height. Female sex and the presence of postoperative articular incongruity correlated with inferior early clinical outcomes.

Effect of metallic tools on scattered radiation dose during the use of C-arm fluoroscopy in orthopaedic surgery

This study investigated the effect of metallic tools on the scattered radiation dose delivered to surgeons' radiosensitive organs while simulating hip surgery using C-arm fluoroscopy. Two phantoms, a pelvis and a Rando phantom, were used to simulate a patient and a surgeon in this study. Photoluminescence dosimeters were inserted into the Rando phantom in the positions of the eye, thyroid and gonad. A drill was positioned above the hip of the pelvis phantom or beside the pelvis phantom of the same height. For each drill location, the scattered radiation dose was measured when the angle to the operator phantom was 45°; this was repeated when the angle was 90°. The scattered radiation doses to the eye, thyroid and gonad when the drill was placed beside the pelvis phantom with 90° angulation to the operator phantom were significantly lower than the reference values and those when the drill was placed beside the pelvis phantom at a 45° angulation to the operator phantom. The scattered radiation doses to the eye and thyroid when the drill was placed above the hip were significantly lower than the references values. Of the four different scenarios, the scattered radiation doses to the eye, thyroid and gonad were lowest when the drill was placed beside the pelvis phantom with 90° angulation. This study showed that the scattered radiation doses to radiosensitive organs were affected by the location and angle of the metallic tools in relation to the operator. Therefore, orthopedic surgeons should consider the effect of metallic tools on the scattered radiation dose during intraoperative use of C-arm fluoroscopy.

Use of iliac crest allograft for Dega pelvic osteotomy in patients with cerebral palsy

Background

Dega pelvic osteotomy is commonly performed procedure in patients with cerebral palsy (CP) undergoing hip reconstructive surgery for hip displacement. However, there has been no study investigating the outcomes after Dega pelvic osteotomy using allograft in patients with CP. This study investigated the outcomes of Dega pelvic osteotomy using iliac crest allograft in CP with hip displacement and the factors affecting allograft incorporation.

Methods

This study included 110 patients (150 hips; mean age 8y7mo; 68 males, 42 females) who underwent hip reconstructive surgeries including Dega pelvic osteotomy using iliac crest allograft. To evaluate the time of allograft incorporation, Goldberg score was evaluated according to the follow-up period on all postoperative hip radiographs. The acetabular index, migration percentage, and neck-shaft angle were also measured on the preoperative and postoperative follow-up radiographs.

Results

The mean estimated time for allograft incorporation (Goldberg score ≥ 6) was 1.1 years postoperatively. All hips showed radiographic union at the final follow-up and there was no case of graft-related complications. Patients with Gross Motor Function Classification System (GMFCS) level V had 6.9 times higher risk of radiographic delayed union than those with GMFCS level III and IV. Acetabular index did not increase during the follow-up period (p = 0.316).

Conclusions

Dega pelvic osteotomy using iliac crest allograft was effective in correcting acetabular dysplasia, without graft-related complications in patients with CP. Furthermore, the correction of acetabular dysplasia remained stable during the follow-up period.

Association of Gross Motor Function Classification System Level and School Attendance with Bone Mineral Density in Patients With Cerebral Palsy

The present study aimed to evaluate bone mineral density (BMD) in children and adolescents with cerebral palsy (CP) and to critically analyze the effects of a variety of factors, particularly the Gross Motor Function Classification System (GMFCS) level, the Caregiver Priorities and Child Health Index of Life with Disabilities questionnaire, and the Pediatric Outcomes Data Collection Instrument (PODCI), on BMD. Fifty patients with CP who underwent dual-energy X-ray absorptiometry were included. Collected data included the extent of involvement, muscle tone, demographic data, factors determined through chart review, and laboratory results. Factors associated with BMD in this group were analyzed by performing multiple regression analysis. The mean Z-scores in male and female patients were -3.252 ± 1.822 and -3.789 ± 1.764, respectively, in the proximal part of the femur and -2.219 ± 1.323 and -2.451 ± 1.434, respectively, in the lumbar spine. In multiple regression analysis, the GMFCS level and the average frequency of missed school in the PODCI were significant factors associated with both femur and lumbar spine BMD. Both the GMFCS level and school attendance were independently associated with BMD and should be considered for the prevention and management of osteoporosis in patients with CP.

Peripheral DXA measurement around ankle joint to diagnose osteoporosis as assessed by central DXA measurement

OBJECTIVE

This study evaluated the correlation between central and peripheral bone mineral density (BMD) of the ankle joint, using dual-energy X-ray absorptiometry (DXA). We also investigated whether peripheral ankle BMD could be used to identify individuals who were diagnosed with osteoporosis, using central DXA.

METHODS

We recruited 134 volunteers aged 20-90 years who agreed to participate in this study. Central BMD of the lumbar spine and left femur, and peripheral BMD of the medial malleolus, distal tibia, lateral malleolus, and talus were measured with DXA.

RESULTS

Among the peripheral sites of the ankle, the highest and lowest BMD were observed in the talus and lateral malleolus, respectively. All peripheral DXA measurements of the ankle joint were significantly correlated with central DXA measurements. There was a good correlation (r: 0.656-0.725) between peripheral and central BMD for the older age group (> 50 years), but fair-to-good correlation (r: 0.263-0.654) for the younger age group (< 50 years). The cut-off values for peripheral BMD of the ankle joint between osteoporosis and non-osteoporosis were 0.548 g/cm² (sensitivity, 89.0%; specificity, 69.0%) for the medial malleolus, 0.626 g/cm² (sensitivity, 83.3%; specificity, 82.8%) for the distal tibia, 0.47 g/cm² (sensitivity, 100.0%; specificity, 65.5%) for the lateral malleolus, and 0.973 g/cm² (sensitivity, 72.2%; specificity, 83.6%) for the talus (p < 0.001).

CONCLUSIONS

This study showed good correlation between peripheral BMD around ankle joint and central BMD for older age group. Further study is required to use the ankle DXA as a valid clinical tool for the diagnosis of osteoporosis and fracture risk assessment.