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Biomedical subjects

G Selvik

Publications and source records attributed to G Selvik.

At least 91 records · Page 5Linked to original sources
PubMed1983

Migration of the tibial component in successful unicompartmental knee arthroplasty. A clinical, radiographic and roentgen stereophotogrammetric study.

Migration of the tibial component in unicompartmental Marmor knee arthroplasty was measured by conventional radiography and roentgen stereophotogrammetry during a 2-year follow-up of six patients operated on for femoro-tibial arthrosis. The clinical course was satisfactory for all six patients. A radiolucent zone developed in all cases, the width of which was greater than 2 mm in one case. By radiography movements of two of the six prosthetic components could be detected. Roentgen stereophotogrammetry showed significant rotational and translatory movements in all six tibial components. In four cases these movements were small not exceeding 1 mm for translation and 1.5 degrees for rotation. The remaining two components showed larger migrations with maximum values of 2.7 mm for translation and 12.6 degrees for rotation. Five of the components tilted backwards about the transverse axis, four tilted away from the centre of the knee about the sagittal axis, and four rotated with the anterior part away from the centre of the knee about the vertical axis. The small movements of the four tibial components may be due to a semi-rigid fixation by connective tissue in the bone-cement interface. Since all knees were asymptomatic, neither the zones nor the minor movements seemed to have any clinical significance within the follow-up period.

Aged↗
PubMed1983

Post-traumatic growth disturbance of the ankle treated by the Langenskiöld procedure. Evaluation by radiography, roentgen stereophotogrammetry, scintimetry and histology: case report.

Progressive growth retardation and varus tilting were observed in a child with an ankle fracture of supination-adduction type initially treated by closed reduction and pinning. The patient was later operated with the Langenskiöld procedure. Preoperatively, roentgen stereophotogrammetric analysis showed decreasing growth rates especially medially in the distal tibia, radionuclide scintimetry manifested reduced activity on the injured side, and tomograms showed a bony bridge medially. The evidence of growth in the distal tibia indicated the existence of an osseofibrous bridge between the epiphysis and the metaphysis. This was also confirmed by the findings at the operation and partly by microscopical investigation of the removed osseofibrous bridge. Postoperative stereophotogrammetric analysis showed reduction of the varus position in two steps. Roentgen stereophotogrammetry permits early detection of a growth disturbance, and evaluation of the effects of therapy.

Ankle Injuries↗
PubMed1982

Posteroanterior traction in maxillonasal dysplasia (Binder syndrome). A roentgen stereometric study with the aid of metallic implants.

The study was undertaken to examine the effect of posteroanterior traction in an 11-year-old boy with maxillonasal dysplasia. Movement of the maxillary bones and of the mandible was recorded, by means of roentgen stereophotogrammetry, in relationship to the frontal bone during and after treatment. In the examined child face-mask therapy mainly influenced the position of the mandible while the recorded advancement of the maxillary bones was slight (0.6 mm.). It is possible that the limited maxillary response to traction may be due to insufficient growth capacity of the circummaxillary sutures in a child with maxillonasal dysplasia. While movement of the maxillary bones and of the mandible during traction conformed with the pattern of treatment effect described by Delaire a total maxillary relapse occurred in the posttreatment observation period (no retention), possibly in adaptation to the retropositioned mandible. In our patient, posteroanterior traction accomplished improvement of the maxillary retrusion in relationship to the mandible only.

Child↗
PubMed1982

Hemifacial microsomia treated with the Herbst appliance. Report of a case analyzed by means of roentgen stereometry and metallic implants.

The effect of Herbst appliance treatment on facial growth of one patient was recorded in terms of displacement of the mandible and the maxillary bones in relation to the frontal bone. The recordings were made with an accuracy of 0.1 degree and 0.05 mm. (S.D.). Before treatment the jaws were displaced posteriorly and to the affected side with growth, increasing the degree of retrognathia and facial asymmetry. During treatment facial growth was redirected and the jaws were displaced anteriorly and to the unaffected side, decreasing th degree of retrognathia and asymmetry. At the same time, however, the tilt of the mandible to the affected side was increased, possibly because of the morphologic and functional conditions of the jaws in hemifacial microsomia. The dental malocclusion was corrected partly through displacement of the jaws and partly through dentoalveolar adaptation.

Activator Appliances↗
PubMed1982

Roentgen stereophotogrammetric analysis of growth pattern after supination--eversion ankle injuries in children.

In a prospective study of ankle fractures in children, the growth rate was registered with a roentgen stereophotogrammetric method. The injuries were classified traumatologically according to Gerner-Smidt and anatomically according to Salter and Harris. Twenty-six ankle fractures were classified as supination--eversion injuries. Of these, eight had intraarticular injuries, 16 had extraarticular injuries of the distal tibia, and two had a zigzag fracture through the growth plate of the distal fibula. Information about growth was obtained within 3 months after fracture, and the growth pattern was found stationary about 6 months after fracture. Five types of growth pattern were observed: Normal growth (1 case), initial growth stimulation of varying length (8), initial and temporary growth retardation (1), initial and permanent growth retardation (4), and initial and permanent growth arrest (7). The other 5 had very low growth rates bilaterally. Roentgen stereophotogrammetry was found useful in extraarticular supination--eversion injuries in girls up to 12 years of age and in boys up to 13 years of age. Intraarticular supination--eversion injuries always appear when there is low remaining growth; because of growth disturbance, no follow-up is indicated. The traumatological classification was found of value in recognizing the different fracture types. Combined with an anatomical classification, high precision in predicting growth disturbance was obtained. However, factors such as trauma, displacement, skeletal maturity, and treatment must be considered. The roentgen stereophotogrammetric method permits early determination of the growth pattern with high accuracy. The growth disturbance can be registered months before this is evident from conventional radiographic examinations.

Adolescent↗
PubMed1982

Roentgen stereophotogrammetric analysis of growth pattern after supination-adduction ankle injuries in children.

In a prospective study of supination-adduction (SA) ankle fractures in children, the post-traumatic growth pattern was registered with a roentgen stereophotogrammetric technique allowing exact determination of the growth rate within 3 months after fracture. It was possible to predict future growth pattern within 6 months. The SA injuries (10 cases) were divided into two stages according to Gerner-Smidt. One Stage I injury (physeal separation through the distal fibula) showed a growth stimulation. Nine Stage II injuries (including a fracture through the medial malleolus) showed four types of growth pattern besides symmetrical growth. The Salter-Harris classification alone showed no obvious correlation to the post-traumatic growth pattern, whereas factors such as age at injury, stage of injury, displacement, and treatment in combination with the Salter-Harris classification contributed to a better prediction of risk of deformity. It was found that displaced Stage II injuries in the younger child had the highest risk of developing a clinically significant varus deformity. Early determination of the post-traumatic growth pattern is of crucial importance in SA injuries with a high risk of growth deformities. Operative treatment in order to restore normal growth can be performed before a severe deformity has developed.

Adolescent↗
PubMed1982

Surface replacement of the hip in chronic arthritis. A clinical, radiographic and roentgen stereophotogrammetric evaluation.

Surface replacement of the hip was performed on nine patients (11 hips) with chronic arthritis. The results were evaluated twice clinically, as well as by radiography and roentgen stereophotogrammetry, an average of 15 and 23 months postoperatively. The early clinical results were promising. One or both of the components were loose in five hips and the acetabular socket had migrated in one hip, as revealed by the radiograms. Roentgen stereophotogrammetry revealed loosening in one hip and migration of one or both of the components in eight hips altogether. The radiograms gave the information needed in the daily routine but roentgen stereophotogrammetry gave more accurate information about early migration. At the third clinical follow-up, an average of 35 months postoperatively, two hips had been reoperated on and two had developed pain.

Adolescent↗
PubMed1982

Roentgen stereophotogrammetric analysis of growth pattern after pronation ankle injuries in children.

In a prospective study of ankle fractures in children, the posttraumatic growth pattern was registered with a roentgen stereophotogrammetric technique. This method allows determination of growth rates within 3 months after fracture, and the prognosis for future growth can be determined within 6-8 months after fracture. The ankle fractures were classified anatomically according to Salter-Harris and traumatologically according to Gerner-Smidt. Nine cases were classified as due to pronation: two pronation-abduction injuries and seven pronation-eversion injuries. The pronation-abduction injuries had Salter-Harris type I injury in distal fibula and tibia, respectively, and showed initial growth stimulation and symmetric growth. The pronation-eversion injuries had a Salter-Harris type II injury in distal tibia and showed three types of growth pattern: initial growth stimulation (3 cases), growth arrest (2 cases), and progressive growth retardation (1 case), besides one case with no significant growth registered bilaterally. Asymmetric growth within the growth region was found in four cases; in three mainly as a varus position, in one mainly as antecurvation of the ankle joint. In conclusion, the pronation-abduction injuries showed growth stimulation, whereas the older showed progressive growth retardation or growth arrest.

Adolescent↗
PubMed1981

Roentgen stereophotogrammetry in high tibial osteotomy for gonarthrosis.

In three cases operated with high tibial osteotomy for medial gonarthrosis the exact method of roentgen stereophotogrammetry with tantalum balls as bone markers (Selvik 1974) was used to study angular and translational movement in three dimensions at the operation and during the healing period. Tibial osteotomy caused angular and translational movements even in planes where correction was not intended, and the stereo technique revealed that stability was not present when knee mobilisation started. Correlation between the stereo values and conventional radiographic measurements were best in the frontal plane (root mean square value of discrepancies 1.3 degrees). Roentgen stereophotogrammetry gives superior information compared with the conventional radiographic technique, but it is concluded that the latter has sufficient accuracy for the clinical assessment of corrections in the frontal plane.

Aged↗
PubMed1981

Growth disturbance after physial injury of distal femur and proximal tibia studied by roentgen stereophotogrammetry.

Longitudinal growth determined by roentgen stereophotogrammetry was registered in three patients with physial injuries in distal femur and in two patients with physial injuries in proximal tibia during 18 months. The injuries in distal femur were classified as Type I, Type I kII and Type IV and in proximal tibia as Type I kII and Type IV in the different cases according to Salter and Harris. Markers of tantalum balls were implanted into the metaphysis and bony epiphysis of distal femur and proximal tibia permitting regular determination of longitudinal growth. Significant growth disturbances was registered in four patients. The Salter-Harris classification was difficult to use to predict growth disturbance after physial injuries around the knee. The roentgen stereophotogrammetric method was found useful to determine normal growth rate and after physial injuries to reveal growth disturbance leading to complete or partial growth arrest resulting in leg length discrepancy or angular deformity. This method facilitates preoperative planning if surgery is needed.

Adolescent↗
PubMed1981

Growth in hemifacial microsomia studied with the aid of roentgen stereophotogrammetry and metallic implants.

Displacement of the mandible and of the maxillary bones with growth was studied in 11 children with hemifacial microsomia. The subjects were from three to 14 years of age at the initial examination and were observed over a period of 350 to 1218 days. Roentgen stereophotogrammetry with the aid of metallic implants proved to be an efficient method for highly accurate recordings of growth relative to the frontal bone. Complicated movements of the jaws occurred and either increased or decreased the degree of facial asymmetry. No correlation could be found between the extent of the mandibular deformity as seen on orthopantomograms and the displacement of the mandible with growth. Generally, the displacement of the maxillary bones corresponded with the displacement of the mandible.

Adolescent↗
PubMed1980

Movement of maxillary segments after expansion and/or secondary bone grafting in cleft lip and palate: a roentgen stereophotogrammetric study with the aid of metallic implants.

The study was undertaken to examine the effects of expansion treatment and secondary bone grafting in cleft lip and palate. Movement of the lateral maxillary segments in four patients with complete bilateral cleft lip and palate (BCLP) was complicated and asymmetric, and a greater relative widening of the dental arch was observed. The least expansion was found in the oldest patient. Bone grafting did not bring about a stable relationship between the segments. The width of the dental arch was mostly maintained despite segmental movement. In one patient with unilateral cleft of the lip and primary palate (UCL) growth in the midpalatal suture followed the pattern observed in noncleft patients but was less extensive. Accurate and comprehensive recording of the relatively small maxillary movements requires that implant stability is checked and that a reference is established outside the maxilla.

Adolescent↗
PubMed1980

Migration of the acetabular socket after total hip replacement determined by roentgen stereophotogrammetry.

UNLABELLED: In order to evaluate the feasibility of a roentgen stereophotogrammetric method for the analysis of the migration pattern of joint prostheses, tantalum balls were implanted into the acetabular socket and the pelvic bone during total hip replacement in four patients with rheumatoid arthritis. During the postoperative period, the migration of the acetabular socket was determined. The observation period varied from 5-24 months. No clinical or radiographic signs of mechanical loosening or infection were noted. All the investigated patients showed a gradual migration of the acetabular socket. The cranial migration measured up to 1.8 mm in 2 years. The migration along the transverse and sagittal axes was less but not constantly directed. The rotatory movements about the three axes varied and measured up to 5.5 degrees in 2 years. The translation and rotation were greatest during the first few months. The results indicate a gradual migration of the acetabular socket in hip arthroplasty in the osteopenic skeleton in rheumatoid arthritis. IN CONCLUSION: roentgen stereophotogrammetry may prove to be a valuable means of analysing the migration of implanted prostheses and detecting prosthetic loosening, thereby increasing the possibility of early and correct diagnosis and therapy.

Acetabulum↗
PubMed1980

Movement of the cleft maxilla in infants relative to the frontal bone. A roentgen stereophotogrammetric study with the aid of metallic implants.

Four implants (tantalum balls 0.5 mm in diameter) were inserted in the frontal bone, and three implants (tantalum pins 1.5 x 0.5 mm) were inserted in each lateral segment of the cleft maxilla of ten infants aged 13 to 42 months. Motion of the maxillary segments was studied relative to the frontal bone by means of roentgen stereophotogrammetry during observation periods from 371 to 868 days. The results were presented by means of computer drawings of the implant triangles projected on the three cardinal planes. With this technique, movement of the maxillary segments could be visualized with a high degree of accuracy. No pattern of movement related to time or type of surgery, to type of cleft (UCLP/BCLP), or to cleft or non-cleft segment could be found.

Cephalometry↗
PubMed1979

Instability and wear of total hip prostheses determined with roentgen stereophotogrammetry.

A roentgen stereophotogrammetric analysis of hip prostheses was made in four patients with rheumatoid arthritis during a postoperative period of 2 years. Implanted tantalum balls, prosthetic femoral head, and ends of the wire in the acetabular socket were used as measurement points. The migration of the prosthetic head and the acetabular socket in relation to the pelvic bone was determined. The difference between the cranial migration of the head and the socket is a measure of the postoperative instability of the hip joint and deformation of the prosthetic components. This deformation occurs in the plastic acetabular socket and is mainly due to wear. The roentgen stereophotogrammetric method can be applied to standard hip orostheses with a metal femoral head and a plastic or metal acetabular socket to study migration or loosening of the prosthesis in relation to the supporting bone, prosthesis instability, and deformation of the prosthetic components.

Adult↗