Kuan-Wen Wu

Analysis of Osteonecrosis Following Pemberton Acetabuloplasty in Developmental Dysplasia of the Hip Long-Term Results

BACKGROUND The favorable results of Pemberton acetabuloplasty in children with developmental dysplasia of the hip have been well reported. We reviewed our long-term results related to osteonecrosis of the femoral head after this surgery, especially with regard to the effect of excessive inferior displacement of the femoral head. METHODS From 1993 to 1997, we performed 167 Pemberton acetabuloplasties in patients with developmental dysplasia of the hip who were eighteen months of age or older. Patients who had had prior treatment or developmental dysplasia of the hip due to neuromuscular disease were excluded. We selected patients who had unilateral developmental dysplasia of the hip, had undergone simultaneous open reduction and Pemberton acetabuloplasty between the ages of eighteen and thirty-six months, and had been followed for a minimum of ten years. Forty-nine patients met these criteria. The patients were divided into osteonecrosis-absent and osteonecrosis-present groups according to the criteria described by Kalamchi and MacEwen. Preoperative, interim follow-up and final radiographs were available for evaluation, as were the results of clinical examination. We used the femoral head inferior displacement percentage, measured on the radiographs, to quantify the amount of excessive correction postoperatively. Outcomes were measured with use of the McKay criteria and the Severin criteria. RESULTS The mean age at the time of surgery was 20.8 months, and the mean duration of follow-up was 134.6 months. Twenty-four patients (49%) were classified as not having osteonecrosis (the osteonecrosis-absent group) and twenty-five patients (51%), as having osteonecrosis (the osteonecrosis-present group). There were no significant differences between the two groups in terms of sex, age, laterality, Tönnis grade, or preoperative acetabular index. Seven of the cases of osteonecrosis were type I, thirteen were type II, one was type III, and four were type IV. The inferior displacement percentage revealed significant differences between the two groups (p < 0.0001). In the osteonecrosis-absent group, 96% of the patients had a radiographically satisfactory result (Severin class I or II); however, only 76% of the patients in the osteonecrosis-present group had a radiographically satisfactory result (p < 0.0001). According to the McKay criteria, there were significant clinical differences between the groups (p < 0.0001). CONCLUSIONS Our results showed significant correlation between excessive reduction of the femoral head and the development of osteonecrosis. In light of the high prevalence of type-II osteonecrosis, we postulated that the lateral epiphyseal branch of the medial circumflex artery was vulnerable to compression with increased inferior displacement of the femoral head. The latest radiographic and functional results corresponded to the severity of the osteonecrosis.

Outcomes of open reduction for developmental dysplasia of the hip: does bilateral dysplasia have a poorer outcome?

BACKGROUND The purpose of this study was to compare the outcomes of surgical treatment in children of walking age with unilateral and bilateral developmental dysplasia of the hip (DDH). METHODS We examined the records of fifty-six children of walking age with bilateral dysplasia and 156 children of walking age with unilateral dysplasia treated with open reduction and pelvic osteotomy with or without femoral osteotomy from 1990 to 2000. The minimum duration of follow-up was five years. The mean age at surgery was thirty-four months in the bilateral group and twenty-five months in the unilateral group. Preoperative radiographs were evaluated to determine the Tönnis grade of the dislocation and the acetabular index, and the latest radiographs were evaluated to determine the Severin classification. The Kalamchi and MacEwen classification was used to assess osteonecrosis, and the McKay classification was used to assess the clinical outcome at the time of the latest follow-up. For the statistical analyses, we selected the worse side in patients in the bilateral group as the index hip if the outcome was asymmetrical and the left hip if the outcome was symmetrical. The Fisher exact and Student t tests were used for comparisons of outcomes between the groups. Multiple logistic regression models were used to analyze factors associated with osteonecrosis and with the McKay classification. RESULTS Age at surgery and preoperative Tönnis grade differed significantly between the groups. Forty-five (80.3%) of the patients in the bilateral group and 135 (86.5%) of the patients in the unilateral group had a satisfactory Severin classification (Ia, Ib, or II); the difference between the groups was not significant. According to the McKay classification, twenty-six (46%) of the patients in the bilateral group had an satisfactory outcome compared with 111 (71%) of the patients in the unilateral group (p = 0.006). Osteonecrosis was significantly greater in the bilateral group as well (p = 0.01). Patient age at surgery and Tönnis grade were risk factors for osteonecrosis. Older age and bilaterality were associated with a poorer McKay classification. The logistic regression analysis was repeated after removing the nineteen patients (34%) in the bilateral group who had an asymmetrical outcome, and this analysis confirmed that asymmetrical outcome was a risk factor for a poorer McKay classification. CONCLUSIONS Our data confirmed that the clinical outcome of bilateral developmental dysplasia of the hip was worse primarily because of asymmetrical outcomes. Age and Tönnis grade played an important role in the risk of occurrence of osteonecrosis. The radiographic outcome according to the Severin classification did not differ significantly between the groups.

Vascular Compression Syndrome of Sciatic Nerve Caused by Gluteal Varicosities

Sciatica is defined as pain or discomfort along the regions innervated by the sciatic nerve. Compression or irritation of lumbar spinal roots, most commonly because of lumbar disc herniation or spinal stenosis, causes sciatica in the vast majority of cases. Although it is rather uncommon, many pathologies have reported to cause nondiscogenic sciatica. A 70-year-old woman presented with intractable sciatic pain which was not elicited by posture change or cough. Sitting on the affected side provoked more pain than standing or walking. Magnetic resonance imaging revealed both spondylolisthesis with lumbar stenosis and compression of the gluteal portion of the sciatic nerve by varicotic gluteal veins. Given the atypical presentation of spinal root compression, gluteal vascular compressive neuropathy was suspected. Ligation and resection of varicotic vein resulted in relief of the patients pain. To our knowledge, cases with varicosity-caused sciatica were limited in the literature review.

Comprehensive review of the functional outcome evaluation of clubfoot treatment: a preferred methodology.

Treatment outcome has been a focus of interest in those who manage clubfeet. Because of a lack of a common evaluation protocol, it has become necessary to establish a universally recognized quantitative measurement to compare and better understand the treatment outcome. The outcome is not merely morphological and radiographic, but it should also include functional and quality-of-life measurements. In this article, we will outline the most commonly used methods of long-term evaluation for congenital clubfeet and recommend the data collection parameters that are most appropriate for a comprehensive functional analysis. This will begin with pretreatment classifications that are important in prognosticating the results. The physical examinations and plain radiographs in standing position are also two fundamental evaluations of clubfoot. Several outcome evaluations have been published in the literature and may be useful depending on the desired metrics. Gait analysis is an additional useful technical tool for analyzing the motion of the foot and ankle and its relation to the whole body function; pedobarography added to the dynamics of the evaluation. Functional quality-of-life questionnaires are increasing in popularity for measuring the total body functional status and the quality of life.

Giant ganglionic cyst of the hip as a rare cause of sciatica

Although ganglionic cysts located at the hip joint are described infrequently, those found in this region are usually small, deep-seated, and asymptomatic. Occasionally, however, a large ganglionic cyst of the hip area is observed that becomes symptomatic following compression of adjacent neurovascular bundles. In this report, the authors describe a 51-year-old man with symptoms of sciatica caused by a giant ganglionic cyst of the posterior hip joint. Because of its intermuscular location, the cyst was not palpable, and was probably misdiagnosed previously as a herniated disc of the lumbar spine. After resection of the cyst, the patients symptoms resolved completely. This case highlights the importance of a detailed clinical examination for patients with multiple degenerative joint diseases.

Medial column stabilization improves the early result of calcaneal lengthening in children with cerebral palsy.

Calcaneal lengthening is a popular surgical treatment for pronated foot deformity. The aim of this study is to assess the effectiveness of medial column stabilization in improving the results of calcaneal lengthening for pronated foot deformity in ambulatory children with cerebral palsy. Twenty-one consecutive (37 feet) children with cerebral palsy with pronated foot deformity who received calcaneal lengthening from 2004 to 2009 were reviewed. Talonavicular stabilizations were performed by either stapling alone or fusion depending on the children’s age and correctability of midfoot deformity. Satisfaction rates were assessed using Mosca’s radiographic, Mosca’s clinical, and Yoo’s clinical criteria. Talonavicular coverage angle was also measured. Results between groups with and without stabilization of the talonavicular joint were compared. Group 1 included 11 children (19 feet) who had no talonavicular stabilization. Group 2 included 10 children (18 feet) who had talonavicular fixation. Groups were further divided into subgroups A [Gross Motor Function Classification System (GMFCS)⩽II] and B (GMFCS≥III). Factors including demography, geographical classification, functional status, and preoperative degree of deformity were similar between the two groups. After the operation, all four radiographic parameters improved significantly. The talonavicular coverage angle was better in group 2 than in group 1. Mosca’s radiographic results were satisfactory in 73.68% of cases in group 1 and 100% in group 2; the difference was statistically significant (P=0.027). As for Mosca’s clinical results, 63.16% in group 1 and 83.33% in group 2 achieved satisfactory results (P=0.156). On the basis of Yoo’s criteria, the results were satisfactory in 57.89% of cases in group 1 and in 94.44% of cases in group 2 (P=0.012). Further analysis on the satisfaction rates between the subgroups showed similar results between the patients in subgroup 1A and 2A, and significantly better results in subgroup 2B than in subgroup 1B. Concurrent stabilization of the talonavicular joint is an effective method to improve clinical and radiographic results of calcaneal lengthening in children with cerebral palsy with pronated feet, and the effect is more significant in children with worse GMFCS levels.

Tendon Transfers Around the Foot: When and Where.

Tendon transfers are invaluable in the treatment of severe childrens foot deformities. They are often preferable to simple releases, lengthening, or fusion in surgical treatment because they provide an active motor function for deformity correction and, when properly selected, the procedures stabilize the foot against progressive deformity. The authors describe 4 commonly used tendon transfer procedures that are useful in childrens foot deformity surgeries.

Classification of Legg-Calvé-Perthes disease.

Although the etiology of Perthes disease remains unknown 100 years after its first description, there are many articles that describe the disease course, final outcome, and results of treatment. A system of classification of the extent and severity of the disease is essential to understanding variability of Perthes, and along with the age of the patient when first affected, is useful in predicting long-term outcomes. Published reports of treatment strategies and their success depend on effective classification of the disease severity and radiographic result at final follow-up concerning head sphericity, congruency with the acetabulum, and arthritis. This article reviews published articles that contain classification systems and details presently used systems that are helpful in understanding and in treating Perthes.

Evaluation of muscular changes by ultrasound Nakagami imaging in Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is the most common debilitating muscular disorder. Developing a noninvasive measure for monitoring the progression of this disease is critical. The present study tested the effectiveness of using ultrasound Nakagami imaging to evaluate the severity of the dystrophic process. A total of 47 participants (40 with DMD and 7 healthy controls) were recruited. Patients were classified into stage 1 (presymptomatic and ambulatory), stage 2 (early nonambulatory), and stage 3 (late nonambulatory). All participants underwent ultrasound examinations on the rectus femoris, tibialis anterior, and gastrocnemius. The results revealed that the ultrasound Nakagami parameter correlated positively with functional severity in the patients with DMD. The median Nakagami parameter of the gastrocnemius muscle increased from 0.50 to 0.85, corresponding to the largest dynamic range between normal and stage 3. The accuracy, sensitivity, and specificity of diagnosing walking function were 85.52%, 76.31%, and 94.73%, respectively. The Nakagami parameter of the rectus femoris and gastrocnemius muscles correlated negatively with the 6-minute walking distance in the ambulatory patients. Therefore, changes in the Nakagami parameter for the gastrocnemius muscle are suitable for monitoring disease progression in ambulatory patients and for predicting ambulation loss. Ultrasound Nakagami imaging shows potential for evaluating patients with DMD.

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.