Perry L. Schoenecker

A Systematic Approach to the Plain Radiographic Evaluation of the Young Adult Hip

Orthopaedic evaluation of hip pain in the young adult population has undergone a rapid evolution over the past decade1,2. This is in large part due to enhanced awareness of structural hip disorders, including developmental dysplasia of the hip and femoroacetabular impingement1-5. Surgical treatment for these disorders continues to be refined6-9, and our ability to identify patients along the spectrum of disease continues to improve10-15. Yet, despite our advances, obtaining an accurate diagnosis can remain challenging, especially in the setting of mild structural abnormalities. Therefore, radiographic examination is a critical component of the diagnostic evaluation and treatment decision-making process. It is essential that physicians have common and reliable radiographic views as well as parameters for plain radiographic assessment that can serve as a foundation for accurate diagnosis, disease classification, and surgical decision-making. Many different radiographic measurements have been described as indicators of structural disease. In particular, measurements such as the lateral center-edge angle of Wiberg16, the anterior center-edge angle of Lequesne17, the ac-etabular index of depth to width described by Heyman and Herndon18, the femoral head extrusion index19, and the Tonnis angle20 have been used as markers for acetabular dysplasia. Similarly, measurements of acetabular version21, the head-neck offset (initially described by Eijer)3,22, and the alpha angle19 have been used in the diagnosis of femoroacetabular impingement. Nevertheless, there is limited literature that provides comprehensive information regarding the details of radiographic evaluation in the young patient with hip symptoms. This paper summarizes the recommendations of the ANCHOR (Academic Network for Conservational Hip Outcomes Research) study group regarding the most important aspects of radiographic technique and image interpretation to evaluate the symptomatic, skeletally mature hip.

Cotrel-dubousset instrumentation for adolescent idiopathic scoliosis.

We evaluated the results of segmental fixation of the spine with Cotrel-Dubousset instrumentation in ninety-five patients who had adolescent idiopathic scoliosis. The instrumentation was used in an attempt to achieve three-dimensional correction of the scoliosis, maintain lumbar lordosis, create thoracic kyphosis, and avoid the need for a postoperative cast or brace. The patients were followed for twenty-four to sixty-four months (average, thirty-five months). Cotrel-Dubousset instrumentation provided an average correction of the coronal curve of 48 per cent at the time of the most recent follow-up. The normal sagittal curves at the thoracolumbar junction and in the lumbar spine were maintained, and the thoracic kyphosis was increased slightly (average, +7 degrees). Apical translation improved an average of 60 per cent, and apical rotation improved an average of 11 per cent. Forced vital capacity improved an average of 21 per cent, and the one-second forced expiratory volume improved an average of 18 per cent. There were no major neurological deficits. A symptomatic pseudarthrosis developed in one patient. Postoperatively, decompensation of the spine developed in five of the first twenty-six patients who had a Type-II or Type-III curve. This complication was avoided in the last twenty-four patients who had a Type-II or Type-III curve by means of a stricter adherence to the definition of a Type-II curve, and reversal of the bend of the rod and the hooks between the caudal neutral and stable vertebrae. The major advantages of Cotrel-Dubousset instrumentation are the stable fixation that is achieved and the preservation of segmental lumbar lordosis.

Long-term follow-up of patients with clubfeet treated with extensive soft-tissue release.

BACKGROUND Although long-term follow-up studies have shown favorable results, in terms of foot function, after treatment of idiopathic clubfoot with serial manipulations and casts, we know of no long-term follow-up studies of patients in whom clubfoot was treated with an extensive surgical soft-tissue release. METHODS Forty-five patients (seventy-three feet) in whom idiopathic clubfoot was treated with either a posterior release and plantar fasciotomy (eight patients) or an extensive combined posterior, medial, and lateral release (thirty-seven patients) were followed for a mean of thirty years. Patients were evaluated with detailed examination of the lower extremities, a radiographic evaluation that included grading of osteoarthritis, and three independent quality-of-life questionnaires, including the Short Form-36 Medical Outcomes Study. RESULTS At the time of follow-up, the majority of patients in both treatment groups had significant limitation of foot function, which was consistent across the three independent quality-of-life questionnaires. No significant difference between groups was noted with regard to the results of the quality-of-life measures, the range of motion of the ankle or the position of the heel, or the radiographic findings. Six patients who had been treated with only one surgical procedure had better ranges of motion of the ankle and subtalar joints (p < 0.004) than those who had had multiple surgical procedures. CONCLUSIONS Many patients with clubfoot treated with an extensive soft-tissue release have poor long-term foot function. We found a correlation between the extent of the soft-tissue release and the degree of functional impairment. Repeated soft-tissue releases can result in a stiff, painful, and arthritic foot and significantly impaired quality of life.

The frog-leg lateral radiograph accurately visualized hip cam impingement abnormalities.

Radiographic evaluation of the anterolateral femoral head-neck junction is essential in diagnosing cam femoroacetabular impingement. We hypothesized the frog-leg lateral radiograph can accurately assess femoral head-neck offset abnormalities associated with cam femoroacetabular impingement. We reviewed the radiographs of 61 hips treated for cam impingement and 24 asymptomatic control hips. To characterize the anatomy of the femoral head-neck junction, the femoral head sphericity, the α-angle of Nötzli et al, and head-neck offset were measured on all radiographs. Asphericity of the femoral head was detected more frequently in hips with impingement on all radiographic views when compared with control hips. The average α-angle was greater in hips with impingement on all views, with the greatest difference between hips with impingement and control hips seen on the frog-leg lateral view (65° for hips with impingement versus 47° for control hips). The average head-neck offset was decreased in hips with impingement on all views. The greatest difference between groups was seen on the frog-leg lateral view (6.6 mm for hips with impingement versus 9.3 mm for control hips). The frog-leg lateral radiograph provides accurate visualization of the femoral head-neck offset in patients being evaluated for femoroacetabular impingement. Level of Evidence: Level II, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Periacetabular osteotomy for the treatment of severe acetabular dysplasia

BACKGROUND The optimal treatment of severe acetabular dysplasia with subluxation of the femoral head or the presence of a secondary acetabulum remains controversial. The purpose of this study was to analyze the extent of surgical correction and the early clinical results obtained with the Bernese periacetabular osteotomy for the treatment of severely dysplastic hips in adolescent and young adult patients. METHODS Sixteen hips in thirteen patients with an average age of 17.6 years (range, 13.0 to 31.8 years) were classified as having severe acetabular dysplasia (Group IV or V according to the Severin classification). Eight hips were classified as subluxated, and eight had a secondary acetabulum. Preoperatively, all patients had hip pain and sufficient hip joint congruency on radiographs to be considered candidates for the osteotomy. All sixteen hips underwent a Bernese periacetabular osteotomy, and six of them underwent a concomitant proximal femoral osteotomy. Postoperatively, the hips were assessed radiographically to evaluate correction of deformity, healing of the osteotomy site, and progression of osteoarthritis. Clinical results and hip function were measured with the Harris hip score at an average of 4.2 years postoperatively. RESULTS Comparison of preoperative and follow-up radiographs demonstrated an average improvement of 44.6 degrees (from -20.5 degrees to 24.1 degrees ) in the lateral center-edge angle of Wiberg, an average improvement of 51.0 degrees (from -25.4 degrees to 25.6 degrees ) in the anterior center-edge angle of Lequesne and de Seze, and an average improvement of 25.9 degrees (from 37.3 degrees to 11.4 degrees ) in acetabular roof obliquity. The hip center was translated medially an average of 10 mm (range, 0 to 31 mm). All iliac osteotomy sites healed. The average Harris hip score improved from 73.4 points preoperatively to 91.3 points at the time of the latest follow-up. Eleven of the thirteen patients (fourteen of the sixteen hips) were satisfied with the result of the surgery, and fourteen hips had a good or excellent clinical result. Major complications included loss of acetabular fixation, which required an additional surgical procedure, in one patient and overcorrection of the acetabulum and an associated ischial nonunion in another patient. Both patients had a good clinical result at the time of the latest follow-up. There were no major neurovascular injuries or intra-articular fractures. CONCLUSIONS The periacetabular osteotomy is an effective technique for surgical correction of a severely dysplastic acetabulum in adolescents and young adults. In this series, the early clinical results were very good at an average of 4.2 years postoperatively; the two major complications did not compromise the good clinical results.

Complications of titanium elastic nails for pediatric femoral shaft fractures.

Limited data exist about complications of titanium elastic nails (TNs) for femur fracture management in pediatric patients. Thirty-nine patients with 43 femoral shaft fractures were identified whose average age was 6.0 years. There were 21 complications (1 intraoperative, 20 postoperative) in 43 femur fractures (49%). There were two major postoperative complications: one septic arthritis after nail removal and one hypertrophic nonunion. Minor postoperative complications were pain at the nails in 13 extremities, nail erosion through the skin in 4, and one delayed union. There was an association between the prominence of TNs and nail pain or skin erosion. Fracture angulation and outcome were associated with the patients weight and size of the nails implanted. Technical pitfalls exist with this implant and can be minimized by leaving less than 2.5 cm of nail out of the femur and by using the largest nail sizes possible.

Periacetabular osteotomy: a systematic literature review

AbstractThe Bernese periacetabular osteotomy is commonly used to treat symptomatic acetabular dysplasia. Although periacetabular osteotomy is becoming a more common surgical intervention to relieve pain and improve function, the strength of clinical evidence to support this procedure for these goals is not well defined in the literature. We therefore performed a systematic review of the literature to define the level of evidence for periacetabular osteotomy, to determine deformity correction, clinical results, and to determine complications associated with the procedure. Thirteen studies met our inclusion criteria. Eleven studies were Level IV, one was Level III, and one was Level II. Radiographic deformity correction was consistent and improvement in hip function was noted in all studies. Most studies did not correlate radiographic and clinic outcomes. Clinical failures were commonly associated with moderate to severe preoperative osteoarthritis and conversion to THA was reported in 0% to 17% of cases. Major complications were noted in 6% to 37% of the procedures. These data indicate periacetabular osteotomy provides pain relief and improved hip function in most patients over short- to midterm followup. The current evidence is primarily Level IV. Level of Evidence: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Coronal decompensation produced by Cotrel-Dubousset "derotation" maneuver for idiopathic right thoracic scoliosis.

From 1985 to 1987,82 patients with idiopathic scoliosis followed 12 to 44 months underwent selective fusion and correction of their right thoracic curves by Cotrel—Dubousset instrumentation using the “derotation” maneuver. Preoperative, postoperative, and follow-up standing anteroposterior roentgenograms of the spine were analyzed. For curves in which there was deviation from the midline (plumb line) and rotation of the lumbar segments, an increased incidence of decompensation was produced after surgery, when posterior Cotrel—Dubousset instrumentation and fusion were carried to the “stable” vertebra with one rod bend and hook alignment on the left sided derotation rod. Previous guidelines established for selective fusion with conventional posterior instrumentation (Harrington or Luque rods) may not be applicable to derotation with Cotrel—Dubousset instrumentation.

Fracture stability after pinning of displaced supracondylar distal humerus fractures in children.

Between January 1, 1994 and December 31, 1997, we evaluated 138 children with displaced supracondylar distal humerus fractures treated by closed reduction and percutaneous pinning. There were 49 type II fractures and 89 type III fractures. Three principal pin configurations were used at the surgeons discretion: 2 lateral pins (42 fractures), 1 medial and 1 lateral pin (37 fractures), and 1 medial and 2 lateral pins (57 fractures). There was no statistically significant difference in clinical stability between these groups. One type III fracture pinned using two lateral pins showed marked rotational instability. We recommend using two lateral pins when treating type II fractures. Type III fractures should be treated using two lateral pins initially and, if the elbow demonstrates significant intraoperative rotational instability, a medial pin should be added. If a medial pin is necessary, and the ulnar nerve cannot be identified by palpation, a small incision should be made and the pin placed under direct vision.

Differentiation between septic arthritis and transient synovitis of the hip in children with clinical prediction algorithms.

BACKGROUND Differentiation between septic arthritis and transient synovitis of the hip in children can be difficult. Kocher et al. recently developed a clinical prediction algorithm for septic arthritis based on four clinical variables: history of fever, non-weight-bearing, an erythrocyte sedimentation rate of >or=40 mm/hr, and a serum white blood-cell count of >12000/mm(3) (>12.0 x 10(9)/L). The purpose of this study was to apply this clinical algorithm retrospectively to determine its predictive value in our patient population. METHODS A retrospective review was performed to identify all children who had undergone a hip arthrocentesis for the evaluation of an irritable hip at our institution between 1992 and 2000. One hundred and sixty-three patients with 165 involved hips satisfied the criteria for inclusion in the study and were classified as having true septic arthritis (twenty hips), presumed septic arthritis (twenty-seven hips), or transient synovitis (118 hips). RESULTS Patients with septic arthritis (true and presumed; forty-seven hips) differed significantly (p < 0.05) from patients with transient synovitis (118 hips) with regard to the erythrocyte sedimentation rate, differential of serum white blood-cell count, total white blood-cell count and differential in the synovial fluid, gender, previous health-care visits, and history of fever. If the four independent multivariate predictors of septic arthritis proposed by Kocher et al. were present, the predicted probability of the patient having septic arthritis was 59% in our study, in contrast to the 99.6% predicted probability in the patient population described by Kocher et al. Statistical analyses demonstrated that the best model to describe our patient population was based on three variables: a history of fever, a serum total white blood-cell count of >12000/mm(3) (>12.0 x 10(9)/L), and a previous health-care visit. When all three variables were present, the predicted probability of the patient having septic arthritis was 71%. CONCLUSIONS Although the use of a clinical prediction algorithm to differentiate between septic arthritis and transient synovitis may have improved the utility of existing technology and medical care to facilitate the diagnosis at the institution at which the algorithm originated, application of the algorithm proposed by Kocher et al. or of our three-variable model does not appear to be valid at other institutions.