Sun Young Joo

Tibial Lengthening Over an Intramedullary Nail with Use of the Ilizarov External Fixator for Idiopathic Short Stature

BACKGROUND The details regarding bone formation and complication rates associated with tibial lengthening over an intramedullary nail with use of the Ilizarov external fixator have not been reported, to our knowledge. The purpose of this study was to review our experiences with this procedure, performed in individuals with idiopathic short stature. In addition, we compared the results of lengthening over a nail, in terms of the observed bone formation and the complications, with those of the conventional Ilizarov method. METHODS Eighty-eight tibiae in forty-four individuals with a mean preoperative height (and standard deviation) of 153.7 +/- 7.2 cm were included in the study. Thirty-two tibial lengthening procedures were performed with the conventional method and fifty-six, with a nail. The increase in the length of the tibia, the external fixation index, the healing index, and complications were assessed. Three specific concerns, including mobility during the lengthening procedure, the time interval before the patient could return to previous activities after completion of the lengthening, and physical activities at the time of final follow-up, were also assessed. RESULTS The mean final height was 160.1 +/- 7.0 cm, and the mean gain in tibial length was 6.2 cm (20.0%). There was no difference in the mean gain in tibial length or the healing index between the groups; however, the external fixation index was lower and there were fewer complications per tibia in the group treated with the lengthening over a nail. The individuals treated with lengthening over a nail coped better with outdoor activities during the treatment period than the individuals treated with the conventional Ilizarov method; however, there was no difference in the time until the individual returned to previous activities or in the ability to carry out physical activities at the time of final follow-up between the groups. CONCLUSIONS Tibial lengthening with use of the Ilizarov external fixator over an intramedullary nail results in new bone formation of a quality equal to that obtained with the conventional Ilizarov method; however, it reduces the duration of external fixation and the rate of complications.

Changes in Dynamic Foot Pressure After Surgical Treatment of Valgus Deformity of the Hindfoot in Cerebral Palsy

BACKGROUND Calcaneal lengthening osteotomy and extra-articular arthrodesis of the subtalar joint are two methods used for the correction of valgus deformity of the heel and forefoot abduction. The purpose of this study was to compare the operative results of these procedures in patients with cerebral palsy who were able to walk. We focused primarily on changes in radiographic parameters and how altered mobility of the subtalar joint by the two operative methods would modify pressure distribution over the plantar surface of the foot. METHODS A total of eighty-one feet in forty-seven patients were included in the study. The mean age at the time of surgery was eight years and one month, and the mean follow-up period was thirty-nine months. The subjects were divided into two groups; Group I consisted of thirty-seven feet in twenty-two patients who underwent a calcaneal lengthening osteotomy, and Group II comprised forty-four feet in twenty-five patients who underwent an extra-articular subtalar arthrodesis. Preoperative and final follow-up radiographs and dynamic pedobarographs were used to evaluate the results. RESULTS The feet in both groups were found to be similarly deformed before surgery, by radiographic measurements and dynamic foot-pressure analysis. Both operative procedures led to improved radiographic indices; however, calcaneal pitch failed to improve after the subtalar arthrodesis. After surgery, the relative vertical impulse was decreased for the hallux, first metatarsal head, and medial aspect of the midfoot in both groups, while it was increased for the lateral aspect of the midfoot and calcaneus. On the other hand, postoperatively, the relative vertical impulse of the medial aspect of the midfoot was higher and the relative vertical impulse of the first through fourth metatarsal heads was lower in the group that had subtalar arthrodesis compared with the group that had a calcaneal lengthening osteotomy and the normal control subjects. CONCLUSIONS Extra-articular subtalar arthrodesis appears to be an effective means to achieve predictable correction of severe valgus deformity of the heel in patients with cerebral palsy who are able to walk; however, supination deformity of the forefoot remains and calcaneal equinus is not corrected. On the other hand, we believe that the calcaneal lengthening osteotomy is the treatment of choice because postoperative foot-pressure distribution more closely approximates the normal foot-pressure distribution.

Surgical Treatment of Calcaneal Deformity in a Select Group of Patients with Myelomeningocele

BACKGROUND The surgical treatment of calcaneal deformity in patients with myelomeningocele has not been uniformly successful in correcting the deformity and preventing recurrence. The purpose of the present study was to examine the results of posterior transfer of the anterior tibial tendon with concurrent procedures in an attempt to balance the muscular forces on the foot and ankle and to obtain a plantigrade foot. We investigated whether surgery improved pressure distribution over the plantar surface of the foot and whether concurrent abnormal movements observed at the knee, hip, and pelvis influenced the surgical outcome. METHODS Thirty-one feet in eighteen patients who were able to walk were included in the study. The mean age at the time of surgery was seven years and four months, and the mean duration of follow-up was forty-seven months. Eight patients were classified as having an L5-level myelomeningocele, and ten patients were classified as having a sacral level myelomeningocele. A tibialis anterior tendon transfer was performed in all patients, and accompanying osseous deformities were also corrected in twelve feet. Measurements on plain radiographs, the results of gait analyses, and dynamic foot pressures that were determined before surgery and at the time of the final follow-up were compared. RESULTS No recurrence or worsening of the deformity was observed in any of the patients, and no other types of foot deformity developed after surgery. Postoperative kinematic studies showed a significant (p < 0.0001) increase in peak plantar flexion and a significant decrease in peak dorsiflexion force of the ankle in the stance phase of gait. Peak pressures under the forefoot and midfoot were increased after surgery, and the relative amount of weight-bearing on the heel as compared with the forefoot was shifted toward more equal weight-bearing. However, less improvement in foot-pressure distribution was observed in patients with increased pelvic rotation before surgery. Those patients also had decreased knee extension in stance phase and increased hip abduction and pelvic obliquity both before and after surgery in comparison with patients who had normal pelvic rotation. CONCLUSIONS Appropriately combined corrective surgical procedures for the treatment of calcaneal deformity in patients with myelomeningocele can effectively reduce the pressure placed on the calcaneus, increase pressures in the forefoot and midfoot, and prevent recurrence of the calcaneal deformity. However, in the presence of excessive pelvic movement in the coronal and transverse planes and decreased knee extension in stance phase, adequate improvement in pressure distribution over the plantar surface of the foot is not likely to occur after this type of foot surgery. LEVEL OF EVIDENCE Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

A new classification for idiopathic genu vara.

Purpose Past classification for the treatment of idiopathic genu vara depended simply on the measurement of distance between the knees, without attention to the rotational profile of the lower extremity. We retrospectively analyzed anatomical causes of idiopathic genu vara. Patients and Methods Twenty eight patients with idiopathic genu vara were included in this study. All patients were surgically treated. To evaluate the angular deformity, a standing orthoroentgenogram was taken and the lateral distal femoral angle and the medial proximal tibial angle were measured. In order to assess any accompanying torsional deformity, both femoral anteversion and tibial external rotation were measured using computerized tomographic scans. A derotational osteotomy was performed at the femur or tibia to correct rotational deformity, and a correctional osteotomy was performed at the tibia to correct angular deformity. Results Satisfactory functional results were obtained in all cases. Genu vara was divided into 3 groups according to the nature of the deformity; group 1 (6 patients) with increased femoral anteversion, group 2 (10 patients) with proximal tibial varus deformity alone, and group 3 (12 patients) with proximal tibial varus deformity accompanied by increased external tibial rotation. Conclusion The success seen in our cases highlights the importance of an accurate preoperative analysis that accounts for both rotational and angular deformities that may underlie idiopathic genu vara.