Three-dimensional computerized tomographic analysis of the deformity of lateral growth disturbance of proximal femoral physis

The potential role of the Alsberg angle as a predictor of lateral growth disturbance of the capital femoral epiphysis in children with developmental dysplasia of the hip treated by closed reduction

PURPOSE

Early diagnosis and prevention of lateral growth disturbance of the capital femoral epiphysis is challenging after treatment for developmental dysplasia of the hip (DDH). The aim of the study was to evaluate the radiographic changes of the Alsberg angle (AA) in normal children and those with DDH, and to assess the role of AA as a potential predictor of lateral growth disturbance of the capital femoral epiphysis.

METHODS

AA was measured on the anterior-posterior pelvic radiographs of 1000 normal children ranging in age from one to ten years and in 66 children (92 hips) with DDH treated by closed reduction (CR). A comparative analysis was performed.

RESULTS

In the normal children, mean AA decreased linearly with age, from 76° at age one year to 65° at age ten years, irrespective of gender and laterality. In children with DDH, the average AA was 81.5°(sd 3.9°; 74° to 87°) prior to CR; it was 75.9° (sd 4.5°; 68° to 83°) in normal children of the same age (p < 0.001). Among the 42 children (64 hips) with successfully and uneventfully treated DDH, AA reached normal values between the ages of five and six years. In contrast, children with lateral growth disturbance of the proximal femur physis (24 children, 28 hips) showed significantly higher AA values in comparison with the age-matched controls.

CONCLUSION

In DDH patients with successful CR, AA could be expected to match normal values in children between the ages of five and six years. On the other hand, AA can be used as an early predictor for lateral growth disturbance of the capital femoral epiphysis.

LEVEL OF EVIDENCE

Level III.

Percutaneous medial hemi-epiphysiodesis using a transphyseal screw for caput valgum associated with developmental dysplasia of the hip

Background

The purpose of this study was to evaluate the radiologic outcome of percutaneous medial hemi-epiphysiodesis using a transphyseal screw for the management of caput valgum associated with developmental dysplasia of the hip (DDH).

Methods

Eighteen hips (18 patients) having caput valgum treated with screw hemi-epiphysiodesis were followed for more than 2 years, and were included in this study. The mean age at the time of the index operation was 8.3 years (range, 4.3 to 10.7 years) and age at the latest follow-up was 12.2 years (range, 9.4 to 16.4 years). The screw in 5 hips was changed into a longer one at postoperative 21.8 months (range, 14 to 29 months) because the proximal femur outgrew the screw. The screws in 11 hips were removed at the mean age of 10.9 years (range, 8.0 to 14.5 years). We retrospectively analyzed the change in various radiologic parameters over time.

Results

The mean Hilgenreiner-epiphyseal angle (HEA) of the operated side was 5.1 ± 11.3° preoperatively, and increased to 20.6 ± 11.3° at the latest follow-up (p = 0.001). The mean difference of the HEA between the operated and contralateral sides was 16.9 ± 15.1° preoperatively, which decreased to 2.4 ± 12.4° at the latest follow-up (p = 0.008). The mean articulo-trochanteric distance of the operated side, which was 3.2 ± 5.5 mm longer than that of the contralateral side preoperatively, became 5.6 ± 9.1 mm shorter at the latest follow-up (p = 0.001). The ratio of femoral neck length of the operated side to that of the contralateral side decreased over the follow-up period. Acetabular shape as measured by the Sharp angle and acetabular roof angle and femoral head coverage as measured by lateral center-edge angle did not change significantly by the index operation. The ratio of medial joint space width of the operated side to that of the contralateral side did not change significantly.

Conclusions

Screw medial hemi-epiphysiodesis can effectively correct caput valgum associated with DDH. However, this technique remains coxa brevis and does not seem to significantly affect acetabular morphology or reduce subluxation.

Loading rates during walking in adolescents with type II osteonecrosis secondary to pelvic osteotomy

Although Pemberton osteotomy has shown a high success rate even in older children, the occurrence of osteonecrosis (ON) remains one of the most severe complications, leading to premature osteoarthritis. Patients with type II ON are characterized by a valgus deformity of the proximal femur with altered musculoskeletal conditions, affecting the ability to attenuate or sustain the impulsive loading from the ground reaction force. It remains unclear whether these conditions also predispose these patients to harmful impulsive loadings. This study aimed to bridge the gap by measuring the loading rates in the lower limbs during level walking in adolescents who were treated during their infancy for unilateral developmental dysplasia of the hip by a pelvic osteotomy, with or without having developed type II ON. Patients with type II ON were found to display increased loading rates, not only at both the affected and unaffected hip, but also at other joints of the affected limb during level walking when compared to patients without ON changes (p < 0.05). These results suggest that patients with type II ON may be at a higher risk of developing premature hip osteoarthritis that is closely related to abnormal loading rates during gait. It is suggested that regular monitoring of joint loading rates in patients with type II ON is necessary for early identification of damaging loadings, and that early intervention aimed at reducing these loadings should be considered. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2199-2206, 2016.

Evaluation of surgical treatment of developmental dysplasia of hip for avascular necrosis of femoral head in children

Developmental Dysplasia of the Hip (DDH) is a common congenital malformation. Avascular necrosis of femoral head is the major complication of both close and open reduction of the dislocated joint. Aim of this study was to determine the incidence and influencing factors in different types of a vascular necrosis of femoral head, following surgical treatment of developmental dysplasia of hip in 1-7 years patients. In this study, 120 patients aged from 1 to 7 years old with DDH who had been undergone open surgery, entered to the study. All of these patients followed up for at least 1 year. Surgery procedures divided to 4 groups: open reduction, open reduction+salter osteotomy, open reduction+femur shortening and open reduction+salter osteotomy+femur shortening. The presence of Avascular Necrosis (AVN) had been appraised. 27.5% of surgeries performed on male and 72.5 on female patients. 35.0% of DDH cases were unilateral and remaining was bilateral. 36 patients (30%) shows radiologic findings of AVN, although all of them placed at group I of Bucholz-Ogden classification. 40% of group A patients, 25% of group B, 14.3% of group C and 36.4% of group D patients developed this findings. Open reduction of DDH in older children is effective in the management of DDH and if all of the contrivance considered in the surgery, the rate of AVN would be low and mild (at least in short term follow ups).

Lateral growth arrest of the proximal femoral physis: a new technique for serial radiological observation

PURPOSE

Lateral growth arrest is recognised as the most common form of avascular necrosis (AVN) seen in the management of developmental dysplasia of the hip (DDH). The purpose of this report is to present a new technique that is of benefit in the early identification and subsequent radiological monitoring of lateral growth arrest and which may permit appropriate timely surgical intervention.

METHODS

We performed a retrospective review of the medical records and serial radiographs of 11 patients (three males and eight females) with lateral growth disturbance in the proximal femoral physis. We devised a new technique (named the 'Tilt angle') for serial radiographic observation of lateral growth arrest.

RESULTS

This study included 11 hips in 11 patients. Ten patients had screw epiphyseodesis performed after progression of lateral growth arrest was noted. One patient did not have screw epiphyseodesis but the results for this patient are included, as they provide an interesting 'control' case for comparison. The average age of screw epiphyseodesis was 12 years. Seven patients demonstrated improvement in their tilt angle following screw epiphyseodesis (i.e. less valgus), one showed no change and two continued to decline.

CONCLUSIONS

Using a new technique to monitor the progression of lateral growth arrest, we noted that screw epiphyseodesis can be used for guided growth of the proximal femoral physis. This technique can be employed for serial radiographic observation of lateral growth arrest and can guide the clinician on the optimal timing of screw epiphyseodesis. Further studies are needed in order to clarify the optimal timing of screw epiphyseodesis.