Biomedical subjects

D R Wenger

Publications and source records attributed to D R Wenger.

At least 73 records · Page 4Linked to original sources

PubMedDate not supplied

Laboratory testing of segmental spinal instrumentation versus traditional Harrington instrumentation for scoliosis treatment.

The authors have tested 51 instrumented calf spines in vitro, using a scoliosis simulator, to evaluate the adequacy of fixation and nature of acute failure seen with various methods of scoliosis instrumentation. Tests were performed in compressive loading, rotation, and forward bending on the following instrumentation systems: (I) Harrington distraction, (II) Harrington distraction plus compression connected by transverse approximators, (III) Harrington distraction plus segmental laminar wires, and (IV) Luque double "L" rods plus segmental laminar wires. The study demonstrated that the addition of segmental fixation to scoliosis instrumentation provides improved stability because of (a) multiple fixation sites and (b) prevention of deformity, especially kyphosis, within the instrumented segment (an important contributor to hook cutout when a single Harrington distraction rod is tested). Failure with the Harrington rod was always by fracture at the metal-bone interface, while failure with the Luque method always occurred outside the instrumented segment.

Animals↗

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Role of exercises in the Milwaukee brace treatment of scoliosis.

Specific exercises designed to strengthen trunk muscles are an integral part of most Milwaukee brace treatment protocols. To assess the effectiveness of these exercises, we established a prospective study evaluating a closely monitored exercise program coordinated with the use of a Milwaukee brace. Between 1973 and 1979, 24 girls treated with a Milwaukee brace for documented progression of primary right thoracic idiopathic scoliosis were selected for the study. All patients were instructed to perform a standard set of exercises based on the program of Blount and Moe (The Milwaukee Brace [Williams and Wilkins, 1973]). Twelve patients who were regular exercisers constituted the exercise group; 12 patients noncompliant in performing regular exercises composed the control group. Both groups remained faithful brace wearers. No significant difference was found between the two groups regarding age at onset, initial curve degree, skeletal maturity, total time in brace, or general activity level. There was no statistically significant difference in curve improvement between the two groups (p = 0.95). This preliminary study suggests that the Milwaukee brace alone is as effective in halting curve progression as a Milwaukee brace plus standard prescribed exercises.

Adolescent↗

PubMedDate not supplied

Extension-abduction contracture of the spastic hip.

Patients with cerebral palsy and fixed hip extension are often unable to sit and therefore lose social and educational opportunities. At Texas Scottish Rite Hospital (Dallas, TX, U.S.A.), 29 patients had hip extension-abduction contractures. Eleven patients with mild involvement were managed with physical therapy. Six patients had moderate involvement and required wheelchair modification to maintain sitting. Twelve patients demonstrated severe contractures that required major soft tissue releases and often femoral shortening osteotomies to regain flexion. Patients with athetosis or rigidity were identified as those most likely to develop extension-abduction contractures either spontaneously or following adductor releases.

Adolescent↗

PubMedDate not supplied

Treatment of acquired hip subluxation in cerebral palsy.

Fifty-seven children with cerebral palsy and subluxated hips underwent soft tissue releases to obtain hip reductions. Eight patients in Group I (preoperatively mildly subluxated hips) had postoperative bracing, all with good results. Twenty-two unbraced patients in Group I had 14 good, 5 fair, and 3 poor results. Thirteen patients in Group II (preoperatively severely subluxated hips) received postoperative splinting with nine good, one fair, and three poor results. The 14 unbraced patients in Group II had one fair and 13 poor results. This study indicates that even severely subluxated hips in spastic children less than 6 years of age can eventually achieve stable reductions provided long-term abduction bracing is used following adequate soft tissue releases.

Casts, Surgical↗

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Acetabular coverage: three-dimensional anatomy and radiographic evaluation.

The three-dimensional relationship between acetabulum and femoral head, known as coverage, was evaluated radiographically using a modified inlet view of the pelvis. The relationship of the anterior edge, the center of the femoral head, and the posterior edge of the acetabulum is a straight line (180 degrees) in normal coverage but less in dysplastic hips. This radiographic method provides anatomical information concerning anterior and posterior coverage. Evaluation of 26 hips delineated problems, including possible danger of anterolateral rotation of the acetabulum in the face of posterior deficiency and inadequacy of posterior coverage after Chiari osteotomy.

Acetabulum↗

PubMedDate not supplied

Blount disease.

Explore the source record for details and available documents.

Bone Diseases, Developmental↗

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Halo application in the infant.

The technique for halo application in very young children is described, with case presentations of three children aged less than 2 years who underwent successful cervical fusion with halo immobilization. Our multiple pin technique for very small children diverges significantly from previously accepted recommendations. With multiple pins, significantly less torque is required to provide stability, allowing a greater range of pin placement sites in areas where the infant skull might otherwise be considered too thin. This technique of halo application provides a safe and effective method of cervical immobilization for infants.

Braces↗

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Tibial physeal closure and genu recurvatum after femoral fracture: occurrence without a tibial traction pin.

Two cases of premature closure of the anterior portion of the proximal tibial physis with associated genu recurvatum deformity in adolescent males who had sustained a closed femur fracture are reported. In both cases, physeal closure occurred without use of a proximal tibial traction pin. In one patient, treatment included distal femoral pin traction; the other patient was treated with skin traction followed by spica cast. We believe that development of recurvatum of the tibia after femoral fracture in children is not necessarily iatrogenic and related to a tibial traction pin, but instead may result from physeal injury incurred at the time of the original trauma.

Child↗

PubMedDate not supplied

Percutaneous muscle biopsy in the diagnosis of neuromuscular disease.

Open biopsy of affected muscle is traditionally used to obtain tissue samples for histologic, histochemical, and biochemical analysis in patients with suspected myopathies. Percutaneous muscle biopsy offers certain advantages over the open technique: it can be performed in an outpatient clinic or as day surgery, usually with a local anesthetic for children greater than 12 years of age, and thus is less costly, more efficient, and less risky. There is also a significant difference in the residual scar. We reviewed the charts of 379 children and adults who had undergone percutaneous muscle biopsy to determine the usefulness of this alternative technique. The analysis could be accurately performed even though the muscle tissue was not at resting length and not oriented in any particular manner, and in nearly all patients sufficient tissue could be obtained for analysis without open biopsy.

Adolescent↗

PubMedDate not supplied

Proximal hamstring lengthening in the sitting cerebral palsy patient.

We retrospectively studied 62 nonambulatory children with spastic quadriplegic cerebral palsy who underwent proximal hamstring lengthening to improve hip and spine positioning. Preoperatively, all had hamstring contracture, with difficulty sitting due to hip extensor thrust and increased kyphosis. Thirty-five patients with follow-up greater than or equal to 2 years were studied using a modified Reimer scale to assess sitting ability. Sitting ability improved significantly (p less than 0.01) postoperatively, along with popliteal angle (p less than 0.001) and straight leg raising (p less than 0.001). Proximal hamstring lengthening is effective in treating severe hamstring contractures in the wheelchair-bound child with cerebral palsy.

Adolescent↗

PubMedDate not supplied

Evaluation of CT scans and 3-D reformatted images for quantitative assessment of the hip.

Hip measurements using three-dimensional (3-D) images and computed tomography (CT) scans were evaluated. The 3-D measurements proved more accurate than CT measurements of femoral and acetabular anteversion. Additionally, accurate 3-D measurements (> 99%) of the femoral neck-shaft angle were provided. Acetabular anteversion determinations by CT scans were systematically decreased as pelvic flexion increased, whereas accuracy was > 96% with 3-D images. The 3-D software allows image rotation in all three reference planes, which minimizes positional errors. A case study is provided to exemplify the shortcomings of conventional imaging techniques and the utility of the quantitative 3-D protocol.

Cadaver↗

PubMedDate not supplied

Quantitative analysis of hip dysplasia in cerebral palsy: a study of radiographs and 3-D reformatted images.

Cerebral palsy patients (31 hips) were evaluated using radiographic and three-dimensional (3-D) images to quantify hip anatomy. The 3-D images overcome distortions caused by joint contractures. Changes were more pronounced in the non-ambulators and characterized by shallow sockets with increased neck-shaft angles. These hips tended to subluxate in a posterior-superior direction and most had defects in the femoral heads. Ambulators had increased femoral anterversion but other hip parameters tended to improve with age. The 3-D measures of roof steepness and socket depth were found to correlate strongly with radiographic parameters of subluxation.

Acetabulum↗

PubMedDate not supplied

Lateral condylar fracture of the humerus following posttraumatic cubitus varus.

Posttraumatic cubitus varus is widely regarded as just a cosmetic deformity. Six cases of lateral condylar fracture of the humerus in children with preexisting cubitus varus due to prior elbow fracture are presented. Five occurred following malunited extension-type supracondylar fractures of the humerus; the other occurred following a lateral condylar fracture complicated by lateral overgrowth. All cases were treated by anatomic reduction (two closed, four open) and percutaneous pinning of the lateral condylar fracture. Three of the six cases subsequently underwent supracondylar osteotomy of the distal humerus to correct the underlying varus malalignment. Biomechanical analysis suggests that both the torsional moment and the shear force generated across the capitellar physis by a routine fall are increased by varus malalignment. Posttraumatic cubitus varus may predispose a child to subsequent lateral condylar fracture and should be viewed as more than just a cosmetic deformity.

Bone Nails↗

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"Trapdoor" procedure for osteonecrosis with segmental collapse of the femoral head in teenagers.

Osteonecrosis of the femoral head in adolescents often leads to serious destructive changes in the hip with resulting significant disability. Between March 1981 and June 1990 we treated 13 teenagers (14 hips) using the "trapdoor" bone grafting procedure for severe femoral head osteonecrosis with articular surface collapse. Nine cases (10 hips) had the trapdoor procedure combined with containment osteotomy of the femur and acetabulum. Thirteen of the 14 hips had adequate follow-up to be included in this report. The main focus of this report is the 10 hips treated with a trapdoor bone grafting plus containment procedure (femoral osteotomy, acetabular osteotomy, or both). At an average follow-up of 4 years 5 months, clinically seven cases (eight hips) had a good result and two had a fair result. Radiographic evaluation showed six hips with a good result, three hips with a fair result, and one with a poor result. None of these 10 hips has yet required hip fusion or replacement arthroplasty, suggesting that trapdoor bone grafting plus containment can serve as a procedure to delay the need for hip fusion in femoral head avascular necrosis in teenagers.

Adolescent↗

PubMedDate not supplied

Pyogenic infectious spondylitis in children: the convergence of discitis and vertebral osteomyelitis.

The outcomes of 47 patients, ranging in age from 7 months to 15 years, 8 months (average, 4 years, 8 months) with presumed pyogenic infectious spondylitis (so-called discitis) were evaluated retrospectively with regard to duration and recurrence of symptoms, and the need for readmission, retreatment, or surgical intervention. Among nonimmobilized patients, 18% (four of 22) receiving intravenous antibiotics, 50% (five of 10) receiving oral antibiotics, and 67% (four of six) receiving no antibiotics (analgesics and bed rest only) had either prolonged or recurrent symptoms or both. Among patients treated with spinal immobilization, one of five receiving concomitant intravenous antibiotics and two of two receiving no antibiotics had a recurrence of symptoms following discontinuation of immobilization. Two patients required surgical drainage of paraspinal abscesses (one cervical and one lumbar). These findings support the contention that so-called discitis is simply pyogenic infectious spondylitis in children and suggest that specific treatment with intravenous antibiotics is more likely to lead to rapid relief of symptoms and signs without recurrence.

Administration, Oral↗

PubMedDate not supplied

Derotational femoral shortening for developmental dislocation of the hip: special indications and results in the child younger than 2 years.

Combining derotational femoral shortening osteotomy with open reduction to reduce the incidence of redislocation and avascular necrosis (AVN) in developmental dislocation of the hip (DDH) was first used only for older children. In special circumstances (teratologic dislocation, syndrome-related DDH, difficult home environment), we have combined femoral shortening with open reduction in 15 children (20 hips) ranging in age from 5 to 23 months old. Fourteen hips required concurrent pelvic osteotomy. Complications included partial AVN in two hips, residual subluxation requiring acetabular osteotomy in two hips, and residual dysplasia in two hips. Radiographic evaluation by the Severin method revealed 15 good or excellent hips and five hips rated fair or less. Hips reduced without pelvic osteotomy produced better radiographic results than those treated with a concomitant augmentation acetabuloplasty (Albee). This procedure can injure the growth centers of the acetabular rim in a very young child. Derotational femoral shortening can be used in special circumstances to achieve reduction in DDH in children younger than 2 years. The surgery is technically demanding, and the surgeon should have extensive prior experience using this method in older children.

Female↗

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Foot growth rate in children age one to six years.

Previous guidelines suggested that children age 2 to 6 years require a shoe size change every 1 to 2 months. Our study of foot growth in 112 children enrolled in a prospective treatment protocol for flatfoot demonstrates that children age 12 to 30 months will require shoe size change every two to three months but that foot growth slows over the subsequent four years, necessitating shoe size change only every 4 months in children up to 4 years of age and every 6 months in children from age 4 to 6 years.

Adolescent↗

PubMedDate not supplied

Pelvic osteotomies for the treatment of hip dysplasia in children and young adults.

Persistent acetabular dysplasia is a well-known cause of premature hip osteoarthritis. In the dysplastic hip, point loading occurs at the edge of the steep, shallow acetabulum. Pelvic osteotomies reduce this load by increasing the contact area, relaxing the capsule and muscles about the hip, improving the moment arm of the hip, and normalizing the forces of weight bearing. The orthopaedic surgeon can choose from among a variety of pelvic osteotomies (e.g., redirectional, reshaping, and salvage) for the purpose of restoring normal anatomy and biomechanical forces across the hip joint. Treatment of residual dysplasia is based on the patient's age and the presence or absence of congruent hip reduction. A Salter or Pemberton procedure is generally appropriate for a child between the ages of 2 and 10. A triple innominate osteotomy can be considered for the older child or adolescent in whom the triradiate cartilage remains open. After triradiate closure, the Ganz periacetabular osteotomy can be considered in addition to the triple innominate osteotomy.

Adolescent↗