Correction of Angular Deformities Due to Focal Fibrocartilaginous Dysplasia Using Guided Growth: A Preliminary Report

Robot-assisted Temporary Hemiepiphysiodesis With Eight-plates for Lower Extremity Deformities in Children

PURPOSE

This study was performed to compare the radiographic results of robot-assisted and traditional methods of treating lower extremity deformities (LEDs).

METHODS

From January 2019 to February 2022, 55 patients with LEDs were treated by temporary hemiepiphysiodesis with eight-plates. They were divided into a robot group and a freehand group. The fluoroscopy time and operation time were recorded. The accuracy of screw placement was measured after the operation using the following parameters: coronal entering point (CEP), sagittal entering point (SEP), and angle between the screw and epiphyseal plate (ASEP). The limb length discrepancy (LLD) and femorotibial angle (FTA) were measured before the operation, after the operation, and at the last follow-up. Patients were followed up for 12 to 24 months, and the radiographic results of the 2 groups were compared.

RESULTS

Among the 55 patients with LEDs, 36 had LLD and 19 had angular deformities. Seventy-six screws were placed in the robot group and 85 in the freehand group. There was no difference in the CEP between the 2 groups ( P >0.05). The robot group had a better SEP (2.96±1.60 vs. 6.47±2.80 mm) and ASEP (3.46°±1.58° vs. 6.92°±3.92°) than the freehand group ( P <0.001). At the last follow-up, there was no difference in the LLD or FTA improvement between the two groups ( P >0.05). The incidence of complications was significantly lower in the robot group than in the freehand group (0/27 vs. 5/28, P <0.05).

CONCLUSION

Robot-assisted temporary hemiepiphysiodesis with eight-plates is a safe and effective method for treating LEDs in children. Robotic placement of screws is superior to freehand placement with respect to the entering position and direction. Although the correction effect for LLD and angular deformity is similar, screw dislocation is less common when using robot assistance.

LEVELS OF EVIDENCE

Level-III. Retrospective comparative study.

Diagnosis and treatment of focal fibrocartilaginous dysplasia of the distal ulna

Focal fibrocartilaginous dysplasia (FFCD) of the distal ulna is a rare benign lesion resulting in progressive radiocapitellar dislocation, limb deformity and limitation in function. This study reported our experience with 10 cases and it aimed to determine a reasonable strategy for diagnosis and treatment. Ten cases treated from 2010 to 2018 in our department were retrospectively reviewed. The diagnosis was based on imaging features. All patients underwent lesion excision in the early stage and five patients required ulna lengthening in the second stage. The radiographic and functional outcomes were analyzed and reported. The median age at diagnosis was 32 months (range, 6-36 months). The median age at the time of surgery was 34 months (range, 10-40 months). The median clinical and radiographic follow-up period was 37 months (range, 24-50 months). The ulna was shortened by an average of 31 mm (range, 27-35 mm). There was no new radial head dislocation after lesion excision. For five cases of radial head dislocation, the median elbow varus angle before ulnar lengthening was 20° and it decreased to 5° after ulnar lengthening. Supination and pronation of the elbow increased from 50°-10° to 70°-30°. We believe that early excision of the lesion can prevent radiocapitellar joint dislocation in patients with FFCD of the ulna. Ulna lengthening can correct limb deformity and improve the range of motion.

Guided Growth for Tibial Recurvatum

Aim and objective

Sagittal guided growth of the distal anterior femur has been shown to be effective for the correction of fixed knee flexion deformity that is encountered in clinical practice. The opposite deformity, namely genu recurvatum, is comparatively uncommon in children. The most common aetiology is post-traumatic. Acute correction by means of osteotomy has significant associated risks. Our objective was to determine whether a posterior 8-plate would suffice in correcting tibial recurvatum and obviate the need for an osteotomy.

Materials and methods

We included a total of five deformities, three boys (one bilateral) and one girl, managed by means of tethering of the posterior proximal tibial physis with a tension band plate. Standard radiographs obtained preoperatively and at follow-up included a standing anteroposterior (AP) of the legs noting limb lengths and the mechanical axis. We also obtained standing lateral views of each knee in maximal extension to measure and compare the posterior proximal tibial angle (PPTA).

Results

The same-day surgery was well tolerated and there were no surgical or post-operative complications. The preoperative PPTA ranged from 106° to 117° and averaged 84° at follow-up. Correction occurred in an average of 20 months (range of 18–24 months). The patient with bilateral recurvatum due to Hurler's syndrome developed unilateral recurrent recurvatum culminating in percutaneous reinsertion of the metaphyseal screw. For each patient, knee hyperextension and associated pseudo-laxity resolved and limb lengths remained equal at follow-up.

Conclusion

Children with progressive genu recurvatum typically present with an insidious onset of symptoms. Guided growth of the posterior proximal tibia is a safe and effective means of correcting the deformity; osteotomy was avoided in this series.

Level of evidence

III – retrospective case series – no controls.

How to cite this article

Stevens P, Stephens A, Rothberg D. Guided Growth for Tibial Recurvatum. Strategies Trauma Limb Reconstr 2021;16(3):172–175.

Growth modulation with tension-band plates for the correction of paediatric lower limb angular deformity: current concepts and indications for a rational use

Growth modulation (GM) with tension-band plates (TBPs) by tethering part of the growth plate is an established technique for the correction of angular deformities in children, and it has increasingly supplanted more invasive osteotomies.Growth modulation with TBPs is a safe and effective method to correct a variety of deformities in skeletally immature patients with idiopathic and pathological physes. The most common indication is a persistent deformity in the coronal plane of the knee exceeding 10°, with anterior and/or lateral joint pain, patellofemoral instability, gait disturbance, or cosmetic concerns. GM has also shown good results in patients with fixed flexion deformity of the knee and ankle valgus.This paper reviews the history of the procedure, current indications, and recent advances underlying physeal manipulation with TBPs. Cite this article: EFORT Open Rev 2021;6:658-668. DOI: 10.1302/2058-5241.6.200098.

Focal fibrocartilaginous dysplasia of the distal femur

Focal fibrocartilaginous dysplasia (FFCD) of the distal femur is a rare disorder that results in a varus or valgus of knee. Due to the small number of cases and unconfirmed natural history of the disease, treatment methods remain variable. This study aimed to determine a strategy to successfully manage distal femoral FFCD. Nine case of femoral FFCD treated in our department between 2008 and 2018, together with 22 cases from literature, were retrospectively reviewed. Tibiofemoral anatomical axis angle (TFA) was used to evaluate and follow the deformities. Treatment methods and outcome were analyzed. Five methods were used to manage the disease: osteotomy with tether release in 14 cases with mean TFA of 29°; simple tether release in eight cases with mean TFA of 31°; guide growth without tether release in 3 case with mean TFA of 27°; guide growth with tether release in 3 case with mean TFA of 27°; and observation in three cases with mean TFA of 23°.Deformity was resolved in all 31 patients. The analysis of the 31 cases in the literature and our experience suggests that femoral FFCD can be successfully managed by simple tether release and curettage. Osteotomy can be avoided. In case of mild deformity (TFA < 25°), it is reasonable to follow-up till 2-3 years of age; if no progress occurs, spontaneous resolution can be expected.

Spontaneous resolution of focal fibrocartilaginous dysplasia of femur on long-term follow-up: case report and review of literature

Focal fibrocartilaginous dysplasia (FFCD) is a rare developmental disorder frequently leading to angular deformities in young children. It most commonly affects the proximal tibia followed by distal femur. There are totally 22 reported cases of FFCD of femur. We report a case of FFCD of distal femur as a cause of varus deformity that was managed nonoperatively. The deformity resolved spontaneously over a period of 8 years. This is the second reported case of spontaneous resolution of angular deformity secondary to FFCD of distal femur. We strongly recommend to observe the behavior of deformity over a period of 24 months before any surgical intervention is planned.

Ulnar focal cortical indentation: a progressive, deforming variant of focal fibrocartilaginous dysplasia

BACKGROUND

Focal fibrocartilaginous dysplasia is a rare growth disturbance of bone resulting in deformity. In the ulna, focal fibrocartilaginous dysplasia is particularly rare, and the characteristic fibroligamentous tether can result in progressive deformity with progressive dislocation of the radial head. The fibroligamentous tether is similar in appearance and function to the Vickers ligament seen in Madelung deformity. The imaging features of ulnar focal fibrocartilaginous dysplasia include a unilateral angular deformity in the ulna with a radiolucent cortical defect and surrounding sclerosis, with secondary radial bowing or radial head dislocation. Focal fibrocartilaginous dysplasia of the ulna has been described using the term ulnar focal cortical indentation.

OBJECTIVE

To review the clinical and radiologic features of four cases of ulnar focal cortical indentation occurring in pediatric patients.

MATERIALS AND METHODS

We retrospectively reviewed picture archiving and communication system and electronic medical record imaging findings with surgical correlation of ulnar focal cortical indentation at two large specialty pediatric hospitals.

RESULTS

Ulnar focal cortical indentation lesions typically arise in the ulnar metaphysis and result in angular forearm deformities with progressive radial deformity including radial head dislocation. Early surgical intervention prevents progression of the deformity and retains range of motion.

CONCLUSION

Ulnar focal cortical indentation, although rare, is likely a progressive form of focal fibrocartilaginous dysplasia resulting in significant deformity and disability. Early recognition of the characteristic imaging features is important for early surgical intervention to preserve range of motion and prevent radial head dislocation.