Biomedical subjects

K Tallroth

Publications and source records attributed to K Tallroth.

At least 19 recordsLinked to original sources

PubMed2004

Preoperative leg-length inequality and hip osteoarthrosis: a radiographic study of 100 consecutive arthroplasty patients.

OBJECTIVE: To assess the leg-length inequality in patients with hip osteoarthrosis (OA) and to evaluate a possible association between the length disparity and side of OA. DESIGN AND PATIENTS: Weight-bearing radiographs of 100 consecutive patients undergoing arthroplasty for primary OA were examined and measured for inequality of leg length, pelvic tilt and severity of OA. RESULTS: The radiographic results showed that preoperatively OA occurred more frequently in the hip of the longer (84%) than the shorter (16%) leg. However, the development of OA did not show a linear relationship with the magnitude of leg-length inequality. CONCLUSION: As hip OA occurred more frequently in the longer leg the authors speculate whether leg-length inequality might predispose to OA in the hip of the longer leg.

Adult↗

PubMed2004

Patellofemoral relationships and cartilage breakdown.

We evaluated the association between patellofemoral relationships and cartilage lesions in patients (age range 15-49) with anterior knee pain without patellar dislocation (n = 24) and in patients with isolated meniscal rupture without a high energy trauma (n = 21). The position of the patella was assessed from knee radiographs, and cartilage lesion was graded and mapped at arthroscopy. In subjects with lateral patellar cartilage lesion the patella tilted laterally (p < 0.01) and was clearly laterally displaced (p < 0.001), compared to those without patellar cartilage lesion. In subjects with central patellar cartilage lesion the patella located high according to the Insall-Salvati index (p < 0.01) and was somewhat laterally displaced (p < 0.05). Compared to subjects without cartilage lesion in the femoral trochlea, the patella was laterally displaced in subjects with lesion in the lateral trochlea (p < 0.001). In conclusion, our results suggest that specific malalignments predispose to patellofemoral cartilage lesion, but prospective studies are needed to confirm the finding.

Adolescent↗

PubMed2002

Bioactive glass as bone-graft substitute for posterior spinal fusion in rabbit.

Bioactive glass S53P4 and autogenous bone were studied as bone graft materials for spinal fusion in a rabbit model. Sixteen rabbits underwent surgery by a dorsal approach. A bioactive glass, a combination of bioactive glass and autogenous bone (70/30 vol%), and autogenous bone were implanted at two thoracolumbar vertebraes for 4 and 12 weeks. The volume, consolidation to vertebrae, and fusion of the graft material were evaluated with plain-film radiology, computed tomography (CT) and bone-mineral density measurements, and compared with histomorphometrical measurements. Radiological consolidation by CT of bone graft to underlying vertebrae at 12 weeks was observable in all groups. This was histologically confirmed as bone was growing from the vertebrae into the graft material. Radiologic fusion of vertebraes was, at 12 weeks, observable in all groups in 50--75% of the cases. The radiologic fusion seen at the CT scans could, however, not be confirmed by histology in any of the three groups. Significant differences for graft material and observation period with the use of bone-mineral density measurements (Hounsfield units) were also observable, with the highest measured values for the bioactive glass group and the lowest for the autogenous bone group. The results indicate that bioactive glass have potential as bone-graft material in spinal fusion. The reliability of radiologic evaluation methods in spinal surgery using bone substitutes is also questioned and discussed.

Animals↗

PubMed2001

MRI of anterior cruciate ligament repair with patellar and hamstring tendon autografts.

OBJECTIVE: Several MRI sequences were used to evaluate the 2-year postoperative appearance of asymptomatic knee with a torn anterior cruciate ligament (ACL) reconstructed with bone-patellar tendon-bone (BTB) and semitendinosus and gracilis (STG) tendon autografts. DESIGN AND PATIENTS: Two groups with successful repair of ACL tear with BTB (n = 10) or STG (n = 10) autografts were imaged at 1.5 T with sagittal and oblique coronal proton density-, T2-weighted and sagittal STIR sequences and plain and contrast-enhanced oblique coronal T1-weighted sequences. The appearance of the graft and periligamentous tissues was evaluated. RESULTS: In all 20 cases, the ACL graft showed homogeneous, low signal intensity with periligamentous streaks of intermediate signal intensity on T2-weighted images. In 10 cases, localised areas of intermediate signal intensity were seen in the intra-articular segment of the graft on proton density- and T1-weighted images. The graft itself did not show enhancement in either of the two groups, but mild to moderate periligamentous enhancement was detected in 10 cases. CONCLUSION: The MRI appearance of ACL autograft is variable on proton density- and T -weighted images. Periligamentous tissue showing contrast enhancement is a typical MRI finding after clinically successful ACL reconstruction.

Adolescent↗

PubMed1999

Bone tunnel enlargement after anterior cruciate ligament reconstruction with the hamstring autograft and endobutton fixation technique. A clinical, radiographic and magnetic resonance imaging study with 2 years follow-up.

The aim of this study was to describe the contrast-enhanced magnetic resonance imaging (MRI) appearance of bone tunnel enlargement detected on radiography after anterior cruciate ligament (ACL) reconstruction with semitendinosus and gracilis tendon endobutton (STG-endobutton) fixation technique. Fourteen patients with a STG-endobutton ACL reconstruction were examined 3 months (n = 1), 1 year (n = 1) and 2 years (n = 12) postoperatively. An age- and sex-matched group with a bone-patellar tendon-bone (BTB) autograft ACL reconstruction with similar follow-up was taken as control. Data on clinical examination, laxity and isokinetic muscle torque measurements, anteroposterior and lateral view radiography were obtained, and knee scores (Lysholm and Tegner) were collected. Contrast-enhanced MRI was performed in the STG-endobutton group with a 1.5-T imager. There were no statistical differences between the groups with respect to clinical findings, stability tests, or knee scores. In the STG-endobutton group the average femoral and tibial bone tunnel diameter detected on anteroposterior view radiography had increased at 2-year follow-up by 33% and 23%, respectively. On MRI the ligamentous graft itself was not enhanced by the contrast medium whereas periligamentous tissue within and around the STG graft bundles showed mild contrast enhancement. In conclusion, the MRI results suggest that enhancing periligamentous tissue accumulated in and around the STG graft associated with the tunnel expansion. In spite of the significant bone tunnel enlargement observed on the follow-up radiography the STG-endobutton knees were stable and the patients satisfied.

Adult↗

PubMed1998

Plain CT of the degenerative lumbar spine.

Degenerative processes of the lumbar spine consist of several disorders of various etiologies with different radiological manifestations. Computed tomography (CT) is well suited for evaluation of these processes since contours of soft tissues, subtle bone structure changes and small calcifications are easily demonstrated with this technique. Spiral CT scanning provides fast data acquisitions, and volumes of high quality for multiplanar reformatting. This review article describes the CT scanning techniques and diagnostic findings of the most common degenerative processes of the lumbar spine.

Humans↗

PubMed1998

Lumbar spinal stenosis: assessment of long-term outcome 12 years after operative and conservative treatment.

The present study focuses on the long-term prognosis of radiographically verified stenosis of the lower lumbar spine. The purpose here was to describe the outcome 12 years after radiographic diagnosis of spinal stenosis and to identify factors predicting disability after operative or conservative treatment. Data were compiled on 75 patients (43 men and 32 women) with changes in functional myelography diagnostic for spinal stenosis. Their mean age at the interview 12 years later was 61 years. The sagittal diameter of the dural sac was measured from baseline myelographs at all intervertebral levels and was corrected for magnification. In the interview, subjective outcome assessment was obtained with a structured questionnaire, and the low-back disorder was scored using the Oswestry disability index. The sagittal diameter of the dural sac was severely stenotic (<7.0 mm) in 32 patients (26 operated), and moderately stenotic (7.0-10.5 mm) in 43 patients (31 operated). The severity of the stenosis significantly predicted disability, even when the effects of age, sex, therapy regimen, and body mass index were adjusted for. For moderate and severe stenosis, the adjusted mean Oswestry indices were 28.4 and 39.1, respectively (p = 0.01). Therapy as such (operative versus nonoperative) did not significantly correlate with later disability. The radiographic severity of lumbar spinal stenosis predicts disability independently of therapy regimen. Randomized clinical trials are needed to establish the indications for surgical and conservative treatment. Radiographic severity of the stenosis should be considered as an effect-modifying or confounding factor in clinical trials and other studies focusing on the outcome of lumbar spinal stenosis.

Aged↗

PubMed1997

Improved accuracy of pedicle screw insertion with computer-assisted surgery. A prospective clinical trial of 30 patients.

STUDY DESIGN: A prospective clinical trial was done to study the accuracy of pedicle screw placement in 30 consecutive computer-assisted orthopedic surgeries. OBJECTIVES: To determine the accuracy and clinical applicability of this new method for pedicle screw insertion. SUMMARY OF BACKGROUND DATA: Conventional screw insertion techniques have been associated with high pedicle screw malplacement rates in cadaver studies and clinical studies with postoperative computed tomography evaluation. METHODS: Thirty transpedicular, low-back, titanium instrumentations were performed with computer-assisted orthopedic surgery. The accuracy of screw placement was evaluated using a sophisticated computed tomography protocol. RESULTS: The total number of pedicle screws was 174. Of these, 139 (79.9%) could be inserted with computer-assisted orthopedic surgery. The malplacement rate of computer-assisted orthopedic surgery screws was 4.3%. In screws that were not inserted by computer-assisted orthopedic surgery, the malplacement rate was 14.3%. One malplaced screw that had not been inserted with computer-assisted orthopedic surgery caused L4 root paresis. CONCLUSIONS: The accuracy of pedicle screw placement using computer-assisted surgery proved to be superior to the accuracy obtained when using conventional techniques.

Bone Screws↗

PubMed1997

Pregnancy and delivery in patients operated by the Harrington method for idiopathic scoliosis.

The course and outcome of 142 pregnancies in 146 patients operated between 1970 and 1975 by the Harrington method for idiopathic scoliosis were studied to determine the effects of scoliosis on pregnancy and childbirth and the effects of pregnancy on the remaining fused and unfused scoliotic curvatures. Occurrence of and sick leave due to low back pain during pregnancy was determined. The patients, all originally treated at the Orthopaedic Hospital of the Invalid Foundation (Orton) in Helsinki, Finland, were invited to a clinical and radiological re-examination on average 19 years following surgery. The results show that pregnancy does not significantly increase fused scoliotic curvatures nor the remaining unfused curvatures. A somewhat higher proportion of children (23%) were delivered by cesarean section than in the general population (15%; P < 0.01), but this result should only be taken as suggestive. Rates of complications of pregnancy and in labor did not differ from those in the background population. The offspring were healthy. Low back pain during pregnancy occurred in about 40% of our patients, but was severe enough to cause sick leave only in 11% of the pregnancies.

Adolescent↗

PubMed1997

Accuracy of pedicle screw insertion: a prospective CT study in 30 low back patients.

A prospective study of the accuracy of titanium pedicle screw placement in 30 low back operations was performed. The postoperative plain radiographs and CT reformation images were evaluated by two independent radiologists. Thirty-two out of 152 screws (21%) perforated the pedicle cortex. One-tenth of the perforations was detected with conventional radiography. In ten patients (33%) all the screws were located within the pedicle. The clinical significance of this study lies in the finding that pedicle perforations are more frequent than is generally believed and that, in spite of the many malplacements, no screw that perforated by less than 4.0 mm caused neurological problems. Only one nerve root lesion was detected.

Adult↗

PubMed1997

The clinical and radiological outcome of the rotating hinged knee prostheses in the long-term.

BACKGROUND AND AIMS: Opinions about hinged knee prostheses vary a lot in different studies. We wanted to examine our series in order to gain long-term information about this kind of knee prosthesis. MATERIAL AND METHODS: Forty-eight (18 Kinematic Hinge and 30 Link Endo Model) rotating hinged knee prostheses were implanted in the Hospital of Invalid Foundation. All knees were retrospectively followed up for an average of 66.3 months and examined for clinical or radiological factors indicating the overall outcome. RESULTS: In the latest review there were 10 patients (20.8%) regarded as having unsatisfactory and 35 patients (79.2%) satisfactory results. Eighty-four per cent of the patients were subjectively satisfied with the operation, mostly because of the painless result. CONCLUSIONS: Taking into account the very poor initial status of these patients, we recommend the rotating hinged prostheses still to be used in severely instable knees awaiting revision.

Adolescent↗

PubMed1996

Femoral component fixation with and without intramedullary plug. A 6-year follow-up.

A total of 113 patients underwent a cemented total hip replacement (THR) operation involving femoral component fixation either without the use of a distal intramedullary plug (n = 57, group 1) or with the plug (n = 56, group 2). We studied the femoral component fixation radiographically at on average 6 years after THR. The cement coating was assessed as technically good in 86% and 95% of groups 1 and 2, respectively. There was radiographically diagnosable loosening of the femoral component at the follow-up in 25 cases in which stems were inserted without the intramedullary plug, and in 6 cases in those with the plug (P < 0.0008), and the mean subsidence of the femoral component was 5 mm in group 1 and 1.5 mm (P < 0.0003) in group 2, respectively. Osteolytic changes around the femoral component were noticed in both groups in equal numbers and with no statistical difference. The use of a distal intramedullary plug in the cementation of the femoral stem results in a better cement coating, reduces femoral component subsidence and ameliorates the loosening rates.

Aged↗

PubMed1996

Experimental telemedicine in orthopaedics.

There have so far been few telemedical applications in orthopaedics. This experiment involved clinicians in three different locations, two in Helsinki and the third in Tampere, consulting one another simultaneously. We used an ATM network to transfer X-ray pictures, digitized by a 12-bit CCD scanner and archived in a central image server. The consultations between the clinicians and the examination of the patient were transmitted by a videoconferencing system using the ISDN. We found that telemedicine offers new possibilities in orthopaedics, for clinical work, for training and for research.

Finland↗

PubMed1996

Shoulder imaging. A review.

Plain radiography still remains the primary imaging method for most shoulder disorders. A good evaluation should include adequate radiographs that provide substantial information about bone and joint pathology. Two anteroposterior projections complemented with a third view fulfill the requirements of two mutually orthogonal images. The third view can be the elevation view or either the axillary or Y-view. Additional projections are used depending on the clinical history and settings. Arthrography is almost the golden standard in the diagnosis of rotator cuff tears. Ultrasound is capable of enabling diagnosis of rotator cuff tears and other soft tissue lesions. The demanding technique requires a dedicated radiologist devoted to musculoskeletal examinations. Of the advanced imaging modalities CT depicts detailed bony images and, combined with arthrography, intra-articular pathology. MR is best suited for soft tissue lesions as well as bone marrow lesions. The choice of an advanced study should be considered according to the clinical history, the clinical findings and the results of the radiography. Undirected use of multiple hightech examinations is unnecessarily costly and may yield ambiguous information.

Adult↗

PubMed1995

Lumbar spine in Marfan syndrome.

Lumbar spine radiographs of 28 patients with Marfan syndrome and a gender and age-matched control group were evaluated for scoliosis and morphologic changes of the L2, L3, and L4 vertebrae. No patient or control subject had any serious low back problems. The Marfan patients showed a high incidence of scoliosis (64%). The incidence of lumbosacral transitional vertebra was also high (18%). The end plates of the vertebral bodies in the Marfan patients were more biconcave than in the control group. In addition, the transverse processes were longer in relation to the vertebral body width in the Marfan group than in the controls. These findings indicate that biconcave vertebral bodies can be added to the list of skeletal manifestations of the Marfan syndrome, and Marfan syndrome to the list of differential diagnoses for biconcave vertebrae ("codfish vertebrae").

Adult↗

PubMed1994

Hyperostosis and osteoarthritis in patients surviving after tetanus.

Twenty patients (12 men and 8 women) who had survived tetanus were examined for bone and joint abnormalities, 1-9 years after the disease. The radiographic findings in the elbows were abnormal in 13 out of 20 patients, as were the shoulders of all 3 patients examined. Insertion hyperostoses were found at the elbow and/or in the shoulder region in 5 (25%) of the patients. The hyperostoses were bilateral in 3 patients. One of the patients with hyperostoses also had calcifications in the soft tissue of the elbow. The abnormalities were associated with mild clinical symptoms. Trauma to the periosteum caused by repeated traction of muscular contractions is possibly the causative mechanism. Twelve patients (60%) had osteoarthritis of the elbow joint presumably secondary to the violent stress to the joint.

Adolescent↗

PubMed1994

Reliability of radiographical measurements of spondylolisthesis and extension-flexion radiographs of the lumbar spine.

We studied the reliability of extension-flexion radiography by analysing intra-observer and inter-observer variations in measurements of 30 patients with established L5-S1 spondylolisthesis. The highest intra-observer angular variations among three radiologists were found at the L5-S1 level (mean 1.6 degrees, S.D. 1.6 degrees, max. 9 degrees) and the highest sagittal translation also at the L5-S1 level (mean 0.6 mm, S.D. 0.8 mm, max. 4 mm). The highest angular inter-observer variation was found at the L5-S1 level (mean 2.6 degrees, S.D. 2.3 degrees, max. 11 degrees) while the highest variation in sagittal translatory movement was found at the L4-L5 level (mean 1.4 mm, S.D. 1.2 mm, max. 6 mm). The mean intra-observer variation for L5 olisthesis was 1.0 mm (S.D. 0.9 mm, max. 5 mm) and the corresponding inter-observer variation 1.3 mm (S.D. 1.1 mm, max. 6 mm). Thus, in general, the overall consistency and concordance were good. The variations in intra-observer and inter-observer readings were similar. Variability in readings did not depend on the magnitude or abnormality of the readings. On the other hand, variability may occur because of difficulty in defining the exact landmarks used for the measurements. We point out that in certain cases the diagnostic value of one single reading of an extension-flexion radiography examination may be questionable.

Adolescent↗

PubMed1993

Surgical treatment of Bertolotti's syndrome. Follow-up of 16 patients.

We surgically treated 16 patients with Bertolotti's syndrome (chronic, persistent low back pain and radiographically diagnosed transitional lumbar vertebra). Eight had posterolateral fusion and another eight resection of the transitional articulation. Thirteen patients had in addition to the chronic low back pain, suffered from repeated episodes or chronic sciatica. In six cases with resection treatment, local injections were administered at the transitional articulation before deciding for resection of the transitional joint; each patient reported transient relief of pain, while this preoperative test did not correlate with successful outcome of treatment. Six patients had to be treated with second operations. Ten of the 16 operatively treated patients showed improvement of the low back pain, and this result was similar in the group treated with fusion and in that treated with resection. Seven had no low back pain at follow-up, and the improvement according to the Oswestry pain scale was similar in the two groups, and statistically significant. Eleven patients still had persisting episodes of sciatica (versus 13 preoperatively). The average disability according to the Oswestry total disability scale was 30%, corresponding with moderate outcome, and both operatively treated groups did equally well. At follow-up the first disc above the fused segments was found to be degenerated in seven out of eight cases, and in the group treated with resection the first disc above the transitional vertebra was degenerated in five cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗