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T Pohlemann

Publications and source records attributed to T Pohlemann.

At least 73 records · Page 4Linked to original sources
PubMed1996

[Pelvic fractures: epidemiology, therapy and long-term outcome. Overview of the multicenter study of the Pelvis Study Group].

Pelvic fractures are rare injuries (3-8%) when compared to fractures in other body regions. They are accompanied by high mortality (5-20%), and the survivors suffer from severe pain and pelvic-related handicaps. The German Pelvic Group (German Chapter of the AO-International & German Trauma Society) started a prospective multicenter study, including ten major trauma centers for collecting a high number of data in a short period of time (1991-1993). All pelvic injuries were documented consecutively using a special set of evaluation sheets. The study closed with 1,722 patients. A 2-year follow-up was completed for 486 patients injured in 1991 and 1992 after type B and C injuries, complex pelvic trauma, acetabulum fractures and a random 25% of A-type injuries (overall follow-up rate 73%). The follow-up included special "out-come" criteria. Of the pelvic ring injuries without significant peripelvic soft tissue involvement, 63.6% were A-type fractures, 21.0% B-type injuries and 15.5% C-type injuries. The rate of operative stabilization was 3.9% after A-type injuries, 37.3% after B-type injuries and 54.3% after C-type injuries. In isolated acetabular fractures ORIF was performed in 38.6%. The total lethality was 7.9% with a significant difference between "complex" pelvic trauma (21.3%) and patients without concomitant peripelvic injuries (7.2%). In 0.9% the pelvic injury was reported as the main cause of death. Pain at follow-up was observed in every classification group, the rate of completely "pain-free" patients being 55% after A-type, 41% after B-type and 27% after C-type fractures. Malfunction of micturia was reported by 7.6% of all patients, sexual malfunction by 11.6% of the males ("erectile dysfunction") and 2.2% of the female ("dysparneuria"). Scaled by the recently developed "outcome score", the radiological result showed anatomical healing after 90.8% of the B-type and 74.6% of the C-type injuries. On the other hand, the clinical result was rated as good or excellent in only 70% of the B-type and 54% of the C-type injuries. Although progress in indications and treatment techniques has shown improved radiological results after unstable pelvic ring injuries when compared to earlier studies, the clinical result still remains unsatisfactory. Further analyses and studies must be conducted to identify the prognostic factors for the late sequelae. Whether it is possible influence these factors by additional surgical intervention cannot be answered at present.

Acetabulum↗
PubMed1996

Epidemiology of pelvic ring injuries.

3260 patients with pelvic and acetabular fractures were assessed using a standardized documentation form by collating the data on 1905 patients treated at the Department of Traumatology of the Hannover Medical School together with those patients treated between 1991 and 1993 in the German Multicentre Study Group (Pelvis) of the German Trauma Society and the German Section of the AO International. 2551 patients had pelvic ring injuries. 61.7% of the patients were multiply injured. 12.2% were suffering a complex pelvic trauma defined as a pelvic injury with concomitant soft tissue injury. The pelvic ring fracture was classified as stable in 54.8% (type A injury), as rotationally unstable in 24.7% (type B injury), and as unstable in translation in 20.5% (type C injury). There were concomitant acetabular fractures in 15.7%. The most frequent single lesions affecting the pelvic girdle were fractures of the ischiopubic bones (transpubic instability), injuries involving the sacroiliac joint (transiliosacral instability), and sacral fractures (transsacral instability). The overall rate of operative stabilizations was 21.6%. Type B injuries were stabilized in 28.9% and type C injuries in 46.7%. The overall mortality rate was 13.4%, depending significantly on the associated extrapelvic trauma. In complex pelvic injuries, the mortality rate was 31.1% whereas for pelvic fractures without concomitant soft tissue injury the rate was only 10.8%.

Accidents, Traffic↗
PubMed1996

Outcome after pelvic ring injuries.

Open reduction and internal fixation of unstable pelvic ring fractures provides the best stability of fixation as well as the best late clinical results. Whereas several studies have supported this both in biomechanical studies and clinical trials, there is still controversy about the long-term outcome of these injuries. A series of 58 patients who had received surgical stabilization of Tile B- and C-type fractures between 1985 and 1990 were followed up for an average of 28 months. The follow-up included a detailed clinical and radiological examination, an evaluation of the patient's general social status and a detailed neurological and urological screening. The data were summarized in a new scoring system rating radiological, clinical and social results independently. Patients suffering B-type fractures showed 79% good and excellent results. Despite the fact that after C-type fractures 50% healed anatomically and 30% healed with a 5 mm or less residual posterior displacement, only 27% of the patients were rated good or excellent. Further studies must be conducted for closer evaluation of risk factors influencing the results after anatomical reconstruction of the pelvic ring.

Female↗
PubMed1996

[The pelvic digital image data bank. Experiences after 18 months in clinical practice].

The simultaneous availability of clinical data and radiographs for orthopedic or traumatology studies is still unsatisfactory. The retrieval of radiological files is especially time-consuming and costly. An existing database holding clinical data for about 2200 consecutive patients after pelvic or acetabular fractures (1972-1995) was supplemented by integration of a commercially available picture database. Data acquisition is performed by a digital photo camera, which is easy to use and provides sufficient resolution (1524 x 1012 pixels). The picture data are optimized but not compressed and, for example, an a.p. pelvic view requires only between 800 KB and 1.5 MB of storage room. Mass storage is performed first on magneto-optical discs and later for permanent storage on CD-ROM. "Clinical" and picture databases are linked by a macro, so the search functions of both databases are available. Thus the clinical data for single patients or group of patients can be analyzed parallel to the corresponding radiographs. By the use of a CD changer, more than 4200 radiographs remain in immediate access. So far more than 3000 radiographs for 350 patients have been acquired. The quality was sufficient for even detailed subclassification and reclassification procedures in over 95% of the cases. Using standard formats and interfaces, the pictures can be either printed in photographic quality or processed as slides for presentation. Using a standard format they have complete access to electronic publishing and mailing. The relatively low price (20,000-30,000 DM) for the complete system and the exclusive use of standard, commercially available hard and software components provide an excellent price/quality relationship and make digital radiograph storage now available for smaller working groups and institutions.

Acetabulum↗
PubMed1995

[Results of follow-up of surgical treatment of complicated acetabulum fractures with extended approaches].

Extended approaches are indicated for complex acetabular fractures. The advantage of extended approaches is the simultaneous exposure of both columns of the acetabulum; disadvantages are the wide exposure of the soft tissue and a high rate of heterotopic ossification. Muscle weakness and necrosis of the muscle have been described. Although there is good exposure with an extended approach, the indication for it is restricted. Between 1972 and 1993, 688 patients with acetabular fractures were treated at the Trauma Department of the Hannover Medical School; 322 had open reduction and internal fixation. Thirty-five patients (10%) were treated with an extended approach. In a retrospective study of 24 patients treated with an extended approach between 1985 and 1993, perioperative data, long-term clinical outcome and radiological outcome were investigated. The aim of the study was to compare the outcome of two groups treated using either the classical extended iliofemoral approach or the Maryland modification. Eleven patients were treated with the extended iliofemoral approach, 13 with the Maryland approach. There were no significant differences in age, type of accident, fracture classification, time to operation, time of operation and blood loss. The postoperative X-ray was anatomic or nearly anatomic in 22 cases; 2 patients had a dislocation of more than 2 mm. The main complications were hematomas and seromas. In both groups we found one thrombosis and one nerve injury with partial recovery. Twenty patients were followed up at least 2 years after trauma, 8 after extended iliofemoral approach and 12 after Maryland approach.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetabulum↗
PubMed1994

[Biomechanical comparison of various emergency stabilization measures of the pelvic ring].

Massive bleeding with shock is still the most frequent reason for early death after complex pelvic trauma. For hemostasis, fracture stabilization in the pelvic ring is an important aspect. By use of the external fixator and introduction of emergency pelvic c-clamps, attempts were made to include pelvic ring stabilization on the early resuscitation algorithm. This biomechanical study compared a simple anterior external fixator (one supraacetabular pin on each side), the emergency pelvic c-clamp (Ganz) and the Browner modification of the clamp ("ACE clamp"). Two fresh-frozen human cadaver pelves were loaded in a one-leg stance model. The displacement and rotations on the site with the fracture were measured with a 3D measurement system. Fracture models included a Tile type B injury and two Tile type C instabilities (pure SI dislocation; transforaminal sacrum fracture). In type B injuries all methods withstood loading with 100% of the body weight (640/700 N). In C-type injuries with SI dislocation the external fixator showed no significant holding force, whereas the two c-clamps withstood loading of 112 N and 160 N. In the transforaminal fracture model no one method withstood a load of more than 40 N. The combination of the clamps with the external fixator increased the holding strength to 66 N and 103 N. Although a single-leg-stance model does not reflect the emergency situation, in which the patient is normally in a supine position, the data recorded are comparable to those observed in earlier investigations.(ABSTRACT TRUNCATED AT 250 WORDS)

Biomechanical Phenomena↗
PubMed1994

The Hannover experience in management of pelvic fractures.

Between 1972 and 1993, 1899 patients with fractures of the pelvis were treated at the authors institution. The pelvic ring was fractured in 1479 patients, and 1029 sustained polytrauma. A retrospective study included four parts: (1) Demographic analysis of 1409 patients showed an increase in the severity of pelvic and general trauma during this period. The 17.7% mortality rate was predicted by the Hannover Polytrauma Score and associated extrapelvic blunt trauma. (2) Residual displacement after operative treatment of the pelvis was analyzed in 221 patients. In C type (Tile) fractures residual displacement correlated with external fixation and solely anterior stabilization. (3) Outcome after operative treatment was analyzed in a consecutive series of 58 patients an average of 2.2 years after trauma. Pelvic pain was frequent (Type B 11%, Type C 66%) and correlated with posterior displacement over 5 mm and primary neurological injuries. (4) Mortality after complex pelvic trauma (pelvic fracture with soft tissue injury) decreased from 48.1% to 29.6% during these years. Standardized protocols for primary care and operative procedures of pelvic injuries optimize therapy. Complex pelvic trauma requires early, aggressive surgical management with surgical hemostasis. Further developments in open reduction and internal fixation of the pelvis focus on minimizing additional soft tissue trauma and implants.

Adolescent↗
PubMed1994

[Scores as decision aids].

Scoring systems are nowadays said to be helpful in decision-making in preclinical and early clinical treatment of multiple trauma patients. To evaluate the importance of these scores in daily routine, we analysed the scores routinely used in our department at the Hannover Medical School. We present three scoring systems: the Polytrauma Score, the Pelvis Score, and the Hannover Fracture Scale. All of these have certain qualities relevant to the aspects of decision-making and prognostic value. The evaluation demonstrates that these scoring systems are genuinely helpful, especially for the inexperienced.

Adult↗
PubMed1993

Fixation of transforaminal sacrum fractures: a biomechanical study.

A transforaminal fracture of the sacrum usually represents the posterior part of an unstable pelvic ring fracture and is associated with a high rate of neurological complications. Nerve root decompression combined with open reduction and internal fixation (ORIF) can be beneficial. Present fixation methods have the disadvantage of extensive bilateral posterior approaches and fixation across the sacroiliac joint. Three methods of internal fixation of the sacrum were compared in a biomechanical study using six fresh pelvic specimens. A fracture model consisting of a transforaminal osteotomy combined with a symphysis disruption in a single-leg stance was used. Standard Harrington sacral bars, an internal fixator, and a newly developed stabilization technique using adapted standard AO/ASIF small-fragment implants ("local osteosynthesis") were compared. Three-dimensional measurement of the fragment movement (goniometer system) showed a maximum displacement of 4.0-4.5 mm after maximal loading (990-1,181 N) and no differences among the implants. The failure load related to body weight was 85% for sacral bars, 74% for the local osteosynthesis, and 58% for the internal fixator. Major displacement under loading was observed in the direction of the foramen axis. The new osteosynthesis technique showed strength comparable to the clinically successfully applied method of stabilization with sacral bars. It adds the theoretical advantage of a minimized approach, without fixation and thus without involvement of the SI joints.

Biomechanical Phenomena↗
PubMed1993

[Results of treatment of polytraumatized patients. A comparative analysis of 3,406 cases between 1972 and 1991].

The treatment data on 3,406 patients with multiple injuries were analyzed retrospectively from the viewpoint of quality control. The diagnosis, therapy, complications and course were documented and the treatment results of two decades (1972-1981 and 1982-1991) compared. Young people with an average age of 31 years were mostly affected: 86% had fractures (40% open injuries), 69% head injuries and 62% thoracic trauma. Head injury together with thoracic trauma was the most frequent injury combination and affected the duration of ventilation therapy and the intensive care course. The relationship between the kind and severity of injury [categorized according to the Hannover Polytrauma Score (PTS)] and the lethality rate was significant. Preclinical treatment (infusion, intubation, thoracic tube) has increased in the past decade, and rescue time has been shortened. For the initial clinical diagnosis, ultrasound and the CT scan have been used more frequently. In patient treatment the elimination of massive hemorrhage still has first priority. Primary stabilization of long tubular bones, mostly of the lower limb, is aspired for. Volume therapy has changed over the last decade, so the risk of acute renal failure has been nearly eliminated. Nowadays late complications, e.g., multiorgan failure, are well in the foreground. Today at Hannover Medical School the average intensive care time is 13.7 days and the hospitalization time 31 days. When the two decades were compared, mortality was seen to have declined from 40% to 18%. In the future if the mortality rate is to be reduced further, this can only be done by treating the cause of post-traumatic organ failure.

Adolescent↗
PubMed1993

[The value of bone scintigraphy in thigh pain following cementless hip prosthesis].

Persisting postoperative pain of the thigh is a common problem of cementless hip endoprostheses occurring in about 15-20% of the patients. We performed a comparative study including patients with (n = 40) and without (n = 45) pain of the thigh. 85 cementless porous-coated anatomic (PCA) hip endoprostheses in 74 patients were examined. All patients underwent clinical examination including a standardized questionnaire, x-ray, and 3-phase bone scintigraphy. Slight or moderate 99mTc-MDP uptake in the area of the greater and lesser trochanter as well as at the tip was a common finding in PCA prostheses in patients without pain and was not a sign of loosening of the hip. Radiologically, there was no difference between patients with and without pain. However, persisting pain of the thigh in patients with PCA prosthesis corresponded with an increased uptake at the tip and the medial and lateral femur, not being a sign of loosening even in this group. The special biomechanical conditions of cementless prostheses causing inhomogeneous intraosseous stress distribution are supposed to be the reason for that.

Adult↗
PubMed1992

Blunt abdominal trauma in cases of multiple trauma evaluated by ultrasonography: a prospective analysis of 291 patients.

Early recognition of blunt abdominal trauma in patients with multiple injuries and in shock is of utmost importance and calls for a rapid screening method. The reliability of diagnostic ultrasonography in detecting hemoperitoneum in patients with multiple trauma was evaluated prospectively. From 1986 to 1990, 291 patients with severe multiple injuries (ISS greater than 20, mean ISS 31.2) were included in the study. Laparotomy was performed on 117 patients (40%). Initial ultrasound (US) findings showed a sensitivity, specificity, and accuracy of 89%, 97%, and 94%, respectively, in detecting intra-abdominal injuries requiring surgical repair. The positive and negative predictive values were 94% and 95%, respectively. A standardized management of frequent repeat US studies can even improve on these numbers. In our department ultrasonography has replaced diagnostic peritoneal lavage (DPL) as the diagnostic study of first choice. Diagnostic peritoneal lavage is reserved for selected cases only.

Abdominal Injuries↗
PubMed1992

[Standardized osteosynthesis techniques for the pelvic ring. Analysis of a patient sample and surgical technique].

A total of 1566 patients with fractures of the pelvis were treated at the Department of Traumatology at the Hannover Medical School between 1972 and 1990. Of these, 1350 patients had fractures of the pelvic ring, 216 isolated acetabulum fractures, and 398 combinations of pelvic ring fractures and acetabular involvement. Of these patients, 718 were admitted with severe polytrauma. For 1254 patients complete files were available for clinical and radiological evaluation of fracture distribution, classification (Tile and anatomical location) and concomitant injuries. A significant increase in the severity of trauma, the severity of the pelvic fractures and the rate of internal stabilization, especially of the posterior pelvic ring, was observed during the observation period. The overall mortality after pelvic fracture was 18.1%. This mortality was correlated to the Hannover Polytrauma Score (PTS) and the associated extrapelvic blunt trauma. Internal fixation of pelvic fractures was performed in 195 patients. Our experience led to standardized procedures for the different fracture locations. In fractures type Tile B, an anterior procedure led in all cases to anatomic or near anatomic healing. In unstable pelvic ring fractures (Tile C), external fixation led to a significantly higher rate of posterior dislocations (over 1 cm) than did internal fixation. In these situations a combined posterior and anterior internal fixation procedure improved the result compared to posterior internal stabilizations alone. As a result, internal stabilization using a standardized technique for every fracture location is recommended for all unstable pelvic ring fractures.

Adolescent↗
PubMed1992

[Primary management of pelvic injuries].

High energy fractures of the pelvis are often associated with genitourinary, neurological, vascular, intestinal, and other skeletal injuries. The pelvic fracture therefore reflects only some of the destructive energy sustained by the patient and is a marker for the associated soft tissue injuries. In these complex pelvic injuries assessment, stabilization, and definitive treatment are complicated. The mortality of complex pelvic injuries is high. Uncontrolled bleeding and septic complications are the main causes of death. The presence of the associated injuries necessitates thorough evaluation in every case. The goals of treatment are prevention of early death from hemorrhage, early detection and treatment of all concomitant injuries, and restoration of the patient to the preinjury level of function. At the scene of the accident, problems affecting the airway, breathing, and circulation should be dealt with first. For prehospital immobilization and transportation of the patient a beanbag should be used. With the aim of improving primary hospital treatment of patients with complex pelvic injuries, a trauma algorithm is presented. This provides for decisive therapeutic steps after brief clinical, radiologic and ultrasonographical assessments. The major questions in the flow chart take the pelvic ring and hemodynamic instability into account. Immediate laparotomy, surgical control of hemorrhage, and open reduction and internal fixation of an unstable pelvic ring are the most important requirements for successful treatment. From 1972 to 1990 the clinical course and outcome of 132 patients with complex pelvic injuries were reviewed. The overall mortality was 34.8%. As the changes in the treatment protocol were implemented mortality decreased from 66.7% (1972-1978) to 18.7% (1985-1990).

Adolescent↗
PubMed1992

[The problem of the sacrum fracture. Clinical analysis of 377 cases].

Sacral fractures are rare injuries that are often neglected because of the general severity of the patient's injuries. They are typical injuries in patients with polytraumata. A "hidden" injury, they are often diagnosed late or are even missed. In a well-documented consecutive series of 1,350 patients with pelvic fractures treated in the trauma department of the Hannover Medical School between 1972 and 1991, a total of 377 sacrum fractures were evaluated in a retrospective study. The cause of the accident, mechanism of injury, concomitant injuries, diagnostic procedures, classification of the pelvic injury (TILE), as well as the classification of the sacrum injury (DENIS), treatment and outcome were analyzed in all cases. Observed complications with special attention to injuries to the lumbosacral plexus were correlated with the classification of the sacrum and pelvis, as well as with a detailed analysis of the fracture pattern and fracture characteristics. In 89.4% at least one additional body region was injured in these patients. PTS (Hannover Polytrauma Score) groups III and IV included 42.5% of the patients. With an improved diagnostic protocol (radiological a.p. views, oblique views and CT scan), the observed rate of sacrum fractures was 33%. Neurological deficits occurred in 15.1% of the patients. In contrast to the literature, the rate of neurological deficits was related more to the degree of pelvic instability (TILE) than to the specific fracture pattern in the sacrum. In stable injuries (TILE A) neurological deficits were only seen in exceptions. In type B injuries the maximum rate was 10%, whereas in unstable fractures (TILE C) the rate of neurological deficits was 32.6% in transalar fractures (DENIS zone I), 42.9% in transforaminal fractures (DENIS zone II), and 63.6% in central fracture types (DENIS zone III). Additional risk indicators for neurological impairment are avulsion fractures of the sacrum, comminuted and bilateral fracture lines. The fracture classification should thus be modified. Our own experience with operative therapy for sacral fractures (open revision of the sacral plexus together with internal stabilization of the fracture) is still limited, but based on the experience presented, further development of the treatment protocol for sacrum fractures should be considered.

Adolescent↗
PubMed1992

[Comparative biomechanical studies of internal stabilization of trans-foraminal sacrum fractures].

A new method of internal stabilization of transforaminal sacrum fractures in unstable pelvic ring fractures was developed by modification of standard AO small-fragment implants. The rationale of this type of stabilization is the use of an unilateral dorsal approach and avoidance of transfixation of the uninvolved SI joints. In a comparative biomechanical study on 8 human cadaver pelvises two types of the new type of stabilization were compared to stabilization with Harrington sacral bars and transiliosacral screw fixation. The fracture model represented a Tile C1 type injury (symphysis disruption and transforaminal sacral osteotomy) on a complete pelvic ring. The anterior stabilization was performed with a 4-hole AO 4.5 mm DC plate in all cases. The load simulation used a one-leg standing model in an upright position with abductor muscle simulation. The pelvises were loaded in 4 load stages of 50%, 80%, 100% and 130% body weight. In each load stage 4 load-unload cycles were completed. With a three-dimensional measurement system (Polhemus 3 Space Motion Tracker) translations an rotations in the fracture plane could be analyzed. Typical behavior in the load-displacement curve was seen in all implants, with settling during the first cycles and permanent displacement after exceeding a specific failure load. The failure load showed no significant differences between implants (99.6-113.6% body weight). The analyses of the persistent displacement, the elasticity and the direction of displacement and rotation showed a typical behavior in the implants, but no differences, which can be interpreted as a significant difference in the stability of the fixation methods. In an additional test the new fixation method showed no loosening in 10,000 cycle loading with 60% body weight. The new stabilization method showed biomechanical results comparable to clinically successful methods of stabilization in the chosen fracture model. Thus, clinical applications of this type of stabilization may be successful.

Adult↗