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G M Plötz

Publications and source records attributed to G M Plötz.

12 recordsLinked to original sources
PubMed2001

Magnetic resonance arthrography of the acetabular labrum: value of radial reconstructions.

The intention was to compare the sensitivity and specificity of radial planes with oblique coronal and oblique axial planes for the detection of labral abnormalities of the acetabulum on magnetic resonance arthrography (MRa). Twenty cadaveric hip joints were examined by radiography and MRa. For MRa, 15 ml of a solution of iodinated contrast material and gadolinium diethylene triamine tetra-acetic acid (Gd-DTPA; 100:1) were injected under fluoroscopic guidance. MRI was performed on a 1.5-T MR scanner with a fat-suppressed 3D-FLASH sequence (TR/TE/flip-angle 42 ms/10 ms/40 degrees; field of view 16 cm, matrix 256 x 256, section thickness 1.5 mm, pixel size 0.7 x 0.7 mm). Multiplanar image reconstructions were done perpendicular to the acetabulum in oblique coronal and oblique axial planes and in radial planes. Macroscopic and histopathologic examination of the labral specimens was performed. Labral lesions were found in 15/20 hips (75%) on pathologic examination. Six hips demonstrated labral degeneration. The labrum was partially detached in 7 hips and completely detached in 2 hips. A flap-like labrum was found in 2 cases, 1 with partial detachment of the labrum and 1 with a degenerated labrum. Using oblique coronal and oblique axial reconstructions, pathologic findings were confirmed by MRa in 9/15 specimens (sensitivity 60%). There were no false-positive findings (specificity 100%, accuracy 70%). Also, 3/6 labral degenerations without detachment, 4/7 partial detachments, and 2/2 complete detachments were correctly diagnosed. Two flap-like labra were not recognized. With radial reconstructions, pathologic findings were correctly confirmed in 12/15 specimens (sensitivity 80%) without false-positive findings (specificity 100%, accuracy 85%). Also, 3/6 labral degenerations without detachment, 6/7 partial detachments, 2/2 complete detachments, and 1/2 flap-like labra were correctly diagnosed. MRa of the acetabular labrum using radial reconstructions is well suited to delineate the acetabular labrum and to diagnose labral detachments. Radial reconstructions allow for perpendicular display of the whole acetabular circumference and are more accurate for the diagnosis of acetabular labral lesions, when compared with oblique coronal and oblique axial reconstructions.

Acetabulum↗
PubMed2000

Magnetic resonance arthrography of the acetabular labrum. Macroscopic and histological correlation in 20 cadavers.

We studied the sensitivity and specificity of magnetic resonance arthrography (MRa) for the diagnosis of lesions of the acetabular labrum in 20 cadaver hips. The MRa results were compared with macroscopic and histological findings. We found that the labrum could be satisfactorily delineated by MRa and that large detachments could be identified satisfactorily. The diagnosis of small detachments and degeneration of the labrum was less reliable.

Acetabulum↗
PubMed1999

[Not Available].

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Journal Article↗
PubMed1999

[MR arthrography of the labrum acetabulare--a radiological-anatomical correlation in 20 cadaveric hips].

PURPOSE: To investigate frequency of acetabular labral lesions in elderly hip joints, and to determine sensitivity and specificity of MR arthrography (MRa) for the detection of these abnormalities. MATERIALS AND METHODS: Twenty cadaveric hip joints were examined by MRa. For MRa, 15 ml of a solution of iodinated contrast solution (Solutrast 300) and Gd-DTPA (100:1) were injected under fluoroscopic guidance. MR imaging was performed on a 1.5 T MR scanner (Vision, Siemens; FOV 16 cm, matrix 256 x 256, fat-suppressed 3D-FLASH). Multiplanar image reconstructions were done perpendicular to the acetabulum in the oblique-coronal, oblique-axial, and radial planes. The labral specimens were examined macroscopically. RESULTS: In 12/20 hips (60%), a labral lesion was found on pathologic examination. In 7 specimens, the labrum was partially or completely detached in the weight-bearing superior region. One flap-like variant of the labrum was seen; in 4 hip joints, the labrum was degenerated (one cystic degeneration). Pathologic findings were confirmed by MRa in 8/12 specimens (sensitivity 67%). All degenerated labra were correctly diagnosed on MRa. Three small labral detachments and the flap-like variant were misinterpreted as being normal. There were no false positive findings (specificity 100%). The accuracy was 80%. Labral lesions were seen in 6/8 and in 6/12 of hips with and without osteoarthritis, respectively. CONCLUSION: MRa is well suited to delineate the acetabular labrum and to diagnose labral abnormalities. Detection of small labral detachments and anatomic variants is difficult and requires some experience. Labral lesions are correlated to osteoarthritis of the hip, but may be frequently seen in the elderly without underlying osteoarthritis.

Acetabulum↗
PubMed1999

[Injury mechanisms in windsurfing regatta].

In a retrospective study, we evaluated the injuries of 44 semi-professional competitors for the German Windsurf Cup, which were suffered from during one windsurfing season. This Cup is the national qualification tour for the annual "production fun board world championship". The subjects, participating in our study were randomly chosen. There were no surf-specific differences between the two groups. The average age was 24.63% had competitive surfing as their hobby, 37% were professional or semi-professional board sailors. The subjects surfed an average of 85 days in 1995. 23 (52%) windsurfers did not get hurt during the entire season. 21 (48%) of them got injured during the 1995 windsurf season. This is an incidence of only one injury per 174 windsurfing days. Only three windsurfers were injured during a competition. The other 18 occurred during training sessions. Most accidents happened because of an overpower situation, i.e. the sail was too big for the wind force (43%), or through negligence on the part of the windsurfer (19%). The most frequent type of the accident was the so called catapult crash (57%). The most common injuries were ligament ruptures of the lower leg (33%) and head burst wounds (19%). Compared with other competitive fun sports (e.g. snow boarding), windsurfing has a lower injury risk. In regard to the injury mechanisms, prophylactic recommendations are made.

Adolescent↗
PubMed1998

Anterior lumbar vertebral translation following translaminar screw fixation. A report of five cases.

Translaminar screw fixation is a good procedure for posterolateral spinal fusion of one or two motion segments. Anterior translation of the upper fused vertebra occurred in 5 of our patients following this procedure. A further fusion with pedicle screw fixation was needed in 2 of them. This complication has been previously reported after decompression operations on the lumbar spine. Translaminar screwing produces slight posterior distraction which pushes forward the upper vertebra. This procedure should be avoided in cases with even minimal anterior translation before operation. Translaminar screw fixation is an ideal technique for fusion of a degenerated segment when the upper vertebra has slipped posteriorly.

Back Pain↗
PubMed1998

[Occipitocervical fusion in chronic polyarthritis].

This report will relate our experience with the y-plate, which we used in the treatment of 39 patients (32 women and 7 men) with a mean age of 62.6 years (range 47 to 79 years) between 1987 and 1994. All patients had rheumatoid arthritis. Occipitocervical fusion was indicated by instabilities within the occipitocervical region and in cases with additional basilar invagination and/or after transoral dens resection for decompression of the spinal cord. The length of the fusion depended on the pathological changes of the subaxial cervical spine. Before surgery, 35 patients suffered from strong and 4 patients from moderate pain in the neck and/or the back of the head. On a linear scale from 0 to 10, the pain was rated as 8:1 on average (range 4 to 10). 31 patients had an instability of the atlantoaxial region and 19 patients a basilar invagination of the odontoid. A cervical myelopathy was found in 20 cases. One surgeon fused the occiput to C2 in 22 cases, to C3-C5 in 8 cases and to C7-T2 in 9 cases. An important factor in this operation is the integration of atlantoaxial screws in order to resist the translational dislocation of C1/C2. In 13 patients a resection of the odontoid had to be performed to adequately decompress the spinal cord. A reduction of C2 without dens resection was performed in cases with reducible instability C1/2. 32 of the patients could be controlled with a minimum follow-up of 12 months (average 32.2 months, range 12 to 66 months). Out of the other 7, 6 patients had died. At the time of follow-up, the pain was rated as 2.3 on average (range 0 to 10). A myelopathy was present in 2 cases. Six patients required further operations on the cervical spine; 4 patients developed an instability at the level(s) below the fusion and an enlargement of the fusion to these levels has been performed. The fusion rate was 96.9%, despite breakage of the implant in 3 and a screw loosening in 2 patients. According to the criteria of Conaty, the result was satisfying in 25 (75%) and not satisfying in 8 patients (25%). These results show the effectiveness of the occipitocervical fusion with the y-plate in rheumatoid arthritis. A transoral dens resection is only indicated in cases with basilar invagination causing a compression of the spinal cord or in such cases where a compression caused by the dens or the retrodental pannus formation cannot be treated by a reduction of the second cervical vertebra alone.

Aged↗
PubMed1996

[Micro-technological anterior discectomy without fusion in cervical disk displacement with radicular symptoms].

Only cervical disc herniation that provokes root compression unresponsive to conservative treatment should be selected for operation. The operative technique must allow adequate removal of the disc and relieve any root pressure without distressing the patient. Operative decompression of the root can be attained via laminectomy and arthrotomy or by way of an anterior approach. With this second procedure, the ventral discectomy can be done in conjunction with an interbody fusion. We report our experience with 216 patients who underwent anterior cervical microsurgical discectomy without fusion between 1980 and 1944. All these patients were suffering from compressive cervical radiculopathy caused by disc displacement without significant degenerative deformation of the motion segment and without manifest segmental instability. The follow-up ranged between 6 and 185 months (average 71 months) in the 175 patients in whom it was possible. Only in 7 patients (4%) is the result unsatisfactory; 79 patients (45%) are completely free of symptoms 99; (56.6%) are very satisfied and 45 (25.7%) satisfied with the result of the procedure.

Adult↗
PubMed1995

Surgical treatment of degenerative spondylolisthesis in the lumbar spine: no reposition without prior decompression.

In the present note, the cause of root compression in cases with degenerative lumbar spondylolisthesis is discussed in order to clarify the best method of surgery and to avoid iatrogenic damage of the cauda equina if a transpedicular fusion is going to be performed. The root compression is due to osteophytes growing out from the upper articular facets and from the upper ridge of the lamina of the lower vertebra. Therefore, the repositioning of the anteriorly displaced vertebra by the instrumentation could lead to the squeezing of the cauda equina between the withdrawn vertebral body and the degeneratively enlarged and hypertrophic facet joints of the lower vertebra. The reposition (even if incomplete) must always be preceded by decompression on both sides, even if radicular complaints are unilateral.

Cauda Equina↗
PubMedDate not supplied

["Recurrent" epiphysiolysis capitis femoris--need for simultaneous stabilization of both hip joints].

In the operative therapy of slipped capital femoral epiphysis, a controversial discussion exists about the sense of a simultaneous stabilization of both epiphyseal plates and about the correct time of removing the implants. We show the epikrisis of two patients to demonstrate our therapy regimen: in the first case the implants were removed too early. The consequence was a further slipping of the femoral epiphysis consecutive on both sides and the necessity of further surgery. In the other case we observed an outgrowing of the implant out of the epiphyseal plate by use of unthreaded wires. The growth plate was not closed. The femoral epiphysis was stabilized again, because an outgrowing compares to an implant removal at a too early stage. These two cases show our point of view. We recommend to stabilize both sides simultaneously with threaded wires and not to remove the implants before closure of the epiphyseal plate. Furthermore, we hold it advisable to perform a restabilization, when the implants grow out of the unclosed epiphyseal plate during adolescence.

Bone Wires↗
PubMedDate not supplied

[Dorsal occipitocervical fusion--indications and results].

STUDY DESIGN: This report will relate to our experience with the occipitocervical fusion with the y-plate, which we used in the treatment of 53 patients. METHODS: 39 of the patients had rheumatoid arthritis. Other indications demanding surgery were posttraumatic conditions, degenerative and congenital lesions, osteomyelitis, tumor and psoriasis arthritis. Before surgery, all patients suffered from pain in the neck and/or in the back of the head. On a linear scale from 0 to 10, the pain was rated as 8.0 in average (range 4 to 10). 33 patients had an instability of the atlantoaxial region and 26 patients a basilar invagination of the odontoid. A cervical myelopathy was found in 23 cases. One surgeon fused the occiput to C2 in 30 cases, to C3-C5 in 14 cases and to C7-T2 in 9 cases. In 17 patients a resection of the odontoid had to be performed before fusion to adequately decompress the spinal cord. RESULTS: 31 of the patients could be controlled with a follow-up of at average 45.9 months. 16 patients had died. At the time of follow-up, the pain was rated as 2.1 in average (range 0 to 8). The myelopathy cleared up in all cases but 3.9 patients required further operations on the cervical spine. 5 patients developed an instability at the level(s) below the fusion and an enlargement of the fusion to these levels had been performed. The fusion rate was 98.1%. The results were satisfying in 25 (80.6%) and not satisfying in 5 patients (19.4%). CONCLUSIONS: These results show the effectiveness of the occipitocervical fusion with the y-plate in a wide range of applications. It offers advantages above other techniques.

Adult↗