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H Thermann

Publications and source records attributed to H Thermann.

At least 19 recordsLinked to original sources
PubMed2001

[Bone segment transport of the femur. Biomechanical value of an unreamed titanium intramedullary nail with reference to stiffness of external distraction systems].

The influence of an unreamed femur nail on axial and torque stiffness of nine different external fixator devices was investigated in a biomechanical study. With a newly developed femur bone model simulating segmental transport, 582 biomechanical tests were performed. The additional use of an unreamed femur nail (UFN) increased axial stiffness of the external fixator devices up to 8108% (average 1673.8-2631.8%) and increased torque stiffness up to 86% (average 47%). The best results could be achieved when combining a small-diameter UFN (9 x 360 mm, Synthes Co.) and external fixator devices with high torque and comparatively little axial stiffness. The use of stainless steel half-pins instead of titanium half-pins improved torque stiffness significantly. Concerning the biomechanical demands made on external fixator devices used for femoral segmental transport, the Hexfix fixator with steel bar and steel half-pins combined with an UFN achieved the best results.

Biomechanical Phenomena↗
PubMed2001

Foot fractures in restrained front seat car occupants: a long-term study over twenty-three years.

OBJECTIVES: To analyze the mechanism of injury for foot and ankle fractures resulting from automobile accidents to create a basis for developing an improved design for protection. DESIGN: Retrospective. SETTING: Level I trauma center with accident research unit. PATIENTS: Automobile accident reports and medical records of individuals injured in the accidents. MAIN OUTCOME MEASUREMENTS: Technical indicators (collision type, impulse angle, deltav, and extent of vehicle deformation) and clinical data (injury location and severity [abbreviated injury scale and injury severity score] and long-term outcome). RESULTS: From 1973 to 1996, 15,559 car accidents were analyzed. Two hundred sixty-one front seat occupants sustained fractures of the foot and ankle (ankle, 41 percent; forefoot, 29 percent; midfoot, 20 percent; and hindfoot, 10 percent). Seventy-five percent of the fractures were classified abbreviated injury scale(foot) 2. The incidence, location, and abbreviated injury scale(foot) category of fractures were similar between driver (n = 210) and front seat passenger (n = 51). Fifty percent of the fractures occurred in head-on collisions and 34 percent occurred in accidents with multiple collisions. The deltav ranged in 82 percent of car crashes between fifteen and sixty kilometers per hour. The deltav and extent of foot compartment deformation correlated with the abbreviated injury scale. During our investigation, deltav increased; the injury severity score decreased; and the extent of deformation did not differ significantly. CONCLUSIONS: Although overall car passenger safety has improved, the relative incidence of foot and ankle fractures has increased. Comparing drivers and front seat passengers, the foot pedals, steering wheel, or the asymmetric design of the dashboard did not influence injury incidence, mechanism, or severity. Foot fractures are mainly caused by the foot compartment deformation in head-on collisions, and therefore improvements in foot compartments are essential for fracture prevention.

Abbreviated Injury Scale↗
PubMed2001

Primary subtalar arthrodesis of calcaneal fractures.

We evaluated retrospectively the long-term results of isolated calcaneal fractures treated with open reduction and internal fixation and a primary subtalar arthrodesis. From 1990 to 1997 258 patients were treated with a calcaneal fracture, for the current study six patients were included. Six different surgeons operated on the patients. The indication for the fusion was based on the comminution of the posterior facet according to the preoperative CT as well as the intraoperative evaluation of destruction of the cartilage. The restoration of length, axes and angles of the calcaneus was almost anatomical in all cases. Follow-up was done at a mean of 4.9 (2.5 - 7.5 years). Using the AOFAS score, the results were good or excellent in five patients. In one patient with a painful arthritis in the talonavicular joint and hyperesthesia of the sural nerve, the results were fair. All returned to their profession within 9 months and had no or only minor daily restrictions. The results are comparable with single surgeon series. We found open reconstruction of the calcaneus with primary fusion of the subtalar joint may be indicated in selected patients and, in these 6 patients led to good results.

Arthrodesis↗
PubMed2001

Healing of the Achilles tendon: an experimental study.

Biomechanical properties of healing ruptures in the Achilles tendon of rabbits were examined after two, four, eight and 12 weeks. Treatment modalities were (n7): a) suture, b) fibrin-glue, c) non-surgical treatment. All animals received a functional aftertreatment consisting of a special orthotic support and free ambulation. For biomechanical testing a fixation-technique was applied that guaranteed intratendinous rupture. After two weeks, the tendons treated with fibrin glue showed better results (stiffness, maximum force to rupture, tensile stress to rupture) compared with the non-surgically treated group. The results for sutured tendons were in between those for the other groups. After four weeks, the results for sutured and for glued tendons were nearly equal and slightly better than the tendons in the non-surgical group. Late results revealed comparable biomechanical properties among all treatment groups and control tendons, suggesting our conclusion that non-surgical treatment is equal to repair using sutures or using fibrin glue as measured by stiffness and tensile stress.

Achilles Tendon↗
PubMed2000

[Healing of autologous cancellous bone transplants and hydroxylapatite ceramics in tibial segment defects. Value of ultrasonic follow up].

The aim of this study was to develop and test a scoring system based on real-time ultrasonography (US), which is able to predict the healing of a bone defect filled with a bone graft substitute or cancellous bone graft. We implanted porous hydroxy-apatite (HA) ceramic blocks into a segmental defect in the tibia of 51 sheep; 14 sheep received autologous bone graft from the iliac crest. Follow-up times were 3, 6 and 12 months. With the exception of the 12-month animals, there was a minimum of 6 animals in each group. At the end of follow-up the tibiae were tested in torsion to failure. These results were correlated with radiographic and ultrasound scores measured on the same specimens. With the scoring system it was possible to describe the osseous integration of the HA ceramic or mineralisation of the cancellous bone graft. Sheep with ceramic implant that developed non-unions showed a significantly lower score than sheep with a sufficient implant integration. A significant correlation between these scores and the biomechanical results was found. We were able to define a cut-off within the scoring system which made the prediction of instability/non-union possible. In our model we were able to predict the osseous integration of HA ceramics and autologous cancellous bone grafts with the use of real-time ultrasound.

Animals↗
PubMed2000

[Quadriceps and patellar tendon ruptures].

Ruptures of the quadriceps as well as the patellar tendon occur in low frequency, but cause major functional deficits of the leg. These injuries usually require operative treatment. Acute quadriceps tendon ruptures are treated by suture repair, using heavy sutures guided through bone tunnels in the patella. Chronic defects and neglected cases require a local tendon transfer, either by a quadriceps tendon turn-down or by a V-Y-plasty of the quadriceps tendon. Ruptures of the patellar tendon are treated by suture of the tendon stumps plus an reinforcement procedure protecting the tendon and avoiding secondary patella alta. Patello-tibial fixation may be achieved by a cerclage technique using wire or an autologous tendon strip, alternatively a patello-tibial external fixator can be applied. In chronic and neglected cases, patellar tendon reconstruction is performed with autologous tendon grafts or with soft tissue allografts. The graft must be protected by a patello-tibial fixation for the first weeks.

Acute Disease↗
PubMed2000

[Achilles tendon rupture].

The treatment of acute of Achilles tendon rupture experienced a dynamic development in the last ten years. Decisive for this development was the application of MRI and above all the ultrasonography in the diagnostics of the pathological changes and injuries of tendons. The question of rupture morphology as well as different courses of healing could be now evaluated objectively. These advances led consequently to new modalities in treatment concepts and rehabilitation protocols. The decisive input for improvements of the outcome results and particularly the shortening of the rehabilitation period came with introduction of the early functional treatment in contrast to immobilizing plaster treatment. In a prospective randomized study (1987-1989) at the Trauma Dept. of the Hannover Medical School could show no statistical differences comparing functional non-operative with functional operative therapy with a special therapy boot (Variostabil/Adidas). The crucial criteria for therapy selection results from the sonographically measured position of the tendon stumps in plantar flexion (20 degrees). With complete adaptation of the tendons' ends surgical treatment does not achieve better results than non-operative functional treatment in term of tendon healing and functional outcome. Regarding the current therapeutic standards each method has is advantages and disadvantages. Both, the operative and non-operative functional treatment enable a stable tendon healing with a low risk of re-rupture (1-2%). Meanwhile there is consensus for early functional after-treatment of the operated Achilles' tendons. There seems to be a trend towards non-operative functional treatment in cases of adequate sonographical findings, or to minimal invasive surgical techniques.

Achilles Tendon↗
PubMed1999

[Subtalar fusion after conservative or surgical treatment of calcaneus fracture. A comparison of long-term results].

In a long-term follow-up we evaluated 40 patients out of 55 (73%) with a subtalar fusion. The operations took place from 5/84 to 5/91. In all cases the indication for the fusion was a post-traumatic arthritis after an intra-articular os calcis fracture. The evaluation of the overall results was carried out with three different scoring systems: a. The Hannover Scoring System. b. The Outcome-questionnaire, rating patient's complaints and the functional status based on the severity-symptom scale and functional status described for Carpaltunnel-syndrome by Levine et al. c. The clinical rating system (CRS) described by Kitaoka et al. The statistical evaluation was performed by analysis of variance (ANOVA). Level of significance was based on P = 0.05 and calculation of Pearson's correlation coefficient. The Os calcis fracture was the cause for the subtalar arthritis in all 40 patients (33 males and 7 females). The primary treatment of the calcaneal fracture was conservative (cons.) using a plaster in 23 patients (57.5%), while 17 patients (42.5%) underwent open reduction and plate fixation (op.). The interval between trauma and subtalar fusion averaged 3.5 years (3 months to 20 years). The interval between subtalar fusion and follow-up averaged 5.2 years (4-14 years). The mean age at the time of reexamination was 47 years (26-61 years). In the present study, complete pain relief could be achieved in 21 (52.5%; 58% op., 50% cons.) patients. A relevant restriction in the range of motion in the ankle joint was found in 26 (65%; 76% op., 58% cons.). In 23 patients (62%; 65% op., 59% cons.) the radiological evaluation revealed a grade 1 degree arthritis of the ankle joint, in the talonavicular joint in 17 patients (42.5%; 41% op., 45% cons.), and in the calcaneo-cuboid joint in 14 patients (35%; 47%., 27% cons.). The statistical analysis revealed a better outcome in the operative group compared with the conservative group, although the operated os calcis fractures in the majority were the more severe fracture types. In all evaluation systems a score between 61 and 69 points could be achieved with no significant difference between the operatively and conservatively treated groups and between the newly developed questionaire and the clinical-radiological scoring systems. For the questionaire this fulfills the requirements for a reliable outcome evaluation.

Adult↗
PubMed1999

[Treatment of recurrence of fibular ligament rupture. Results of a prospective randomized study].

Previous studies concerning ruptures of the lateral ligaments of the ankle dealt with acute first ruptures. There are a few articles about chronic instability of the ankle but no prospective investigations have been reported concerning the treatment of recurrent ruptures. Good results were obtained following after non-operative treatment of acute ruptures of the fibular ligaments of the ankle joint. This prospectively randomized study was commenced to test whether recidivations of the rupture of the lateral ligaments can also be treated non-operatively or if they are in need of operative repair. The second question to be answered was whether these injuries should be treated differently depending on the treatment of the first rupture. From December 1986 to November 1989, 109 patients with a recidivation of a rupture of the ankle joint lateral ligaments were included in this prospective trial at the Department of Trauma Surgery, Hannover Medical School. They were divided into two groups depending on the therapy used to treat the first injury: The relapse was classified as a second-stage-rupture in cases where treatment of the first ligament rupture did not involve an operation and as a rerupture if the initial rupture was surgically repaired. Half of each group was treated randomly either with surgical ligament repair or without. A total of 100 patients (92%) at an average age of 24 years (11 to 49 years) was seen for follow-up examination one year after the relapse: The follow-up included the patient's subjective assessment, a clinical examination, and stress radiography. A 70 point score was used for evaluation of the total result. Two wound infections requiring reoperation were observed in the operative treatment groups. The follow-up examination revealed better results in both operative treatment groups (A and C), which was statistically significant (P < 0.05). Patients with a second-stage-rupture showed a significantly higher (P < 0.001) stability by stress radiography after surgical treatment (group A) in contrast to non-operative treatment (group B). In addition, the subjective and clinical results indicated a tendency towards better results which were not statistically significant (P < 0.09 and P < 0.07). In cases of rerupture the patient's subjective assessment revealed significantly more (P < 0.05) complaints after non-operative treatment (group D). Clinical results were comparable, and radiologic assessment showed a tendency towards higher joint stability after surgical treatment (group C), although it was not statistically significant (P < 0.07). Based on the results presented, the authors recommend the surgical repair of ankle joint ligaments in cases of second-stage- or rerupture.

Adolescent↗
PubMed1999

[Treatment of intraarticular calcaneal fractures in adults. A treatment algorithm].

Significant progress has been made in terms of the management of calcaneal fractures. This is reflected in the marked decrease in complication rates associated with the current intervention of these potentially devastating injuries. The treatment priorities that, in the authors opinion, are key to achieve best results in a displaced calcaneal fracture are anatomic reconstruction of the entire calcaneus: articular surfaces, height, alignment, and length, with a function directed postoperative management. The value of these priorities are confirmed by the authors longterm follow-up results as presented here. To reemphasize, conservative treatment should be considered only in cases of extraarticular fractures, minor displaced intraarticular fractures in nonambulatory patients, and in cases where there is a clear contraindication for surgery. Regarding the technical requirements for an anatomic reconstruction, the os calcis fracture should be categorized as a procedure for experts. In two-part fractures, according to the Sanders classification, an anatomical reduction is obtainable in more than 80%-90% of cases. However, in consideration of the articular cartilage damage, a 70% rate of good to excellent clinical results seems realistic. In three-part fractures, anatomic reduction is attainable in about 60% of cases with a 70% rate of good results. These two subgroups comprise about 90% of all calcaneus fractures. It is the authors recent experience to optimize the extended lateral approach using posteromedial and anterolateral windows, so that an anatomic reduction in more than 60% of Sanders Type III os calcis fractures can be achieved. Further scientific work in this area of trauma orthopedics would benefit most from a general consensus on a fracture classification system and on a clinical scoring system, with 5 year follow-up studies using these treatment methods and evaluation systems.

Adult↗
PubMed1999

[Os trigonum syndrome].

The os trigonum syndrome is an entity causing posterior ankle pain and occurs mostly with typical sports activities. Diagnosis and differential diagnosis are presented. Typical complaints and therapeutic procedure are demonstrated in one case. Therapy includes different non-operative methods, resistance to non-operative procedures is an indication for excision of this ossicle.

Adolescent↗
PubMed1999

[Fractures of the foot region of car drivers and passengers. Occurrence, causes and long-term results].

During 1973 and 1989, 6,378 car accidents with 8,931 injured persons were evaluated in the area of Hannover. 3,267 car drivers and passengers sustained fractures overall and 148 (4.5%) fractures of the foot. A major role in the etiology of the foot fractures evolves from the deformation of the foot room. Driver and front seat passenger showed similar injuries. Among the 286 single fractures, the forefoot was affected most often (45%), followed by ankle (38%), midfoot (11%) and hindfoot (6%). 5% were open fractures. The long term results were estimated upon the limitation of working ability caused by the foot injury in relation to the entire working ability. The evaluation concludes that the foot fractures especially in combination with other injuries were frequently not recognized within the primary examination and therefore underestimated. The long-term outcome leaded to a high degree of impairment due to foot fractures.

Accidents, Traffic↗
PubMed1999

[Functional treatment of acute Achilles tendon rupture. A histological, immunohistological and ultrasonographic analysis of the animal model].

In 105 rabbits the course of healing was examined at 1, 2, 4, 8 and 12 weeks (21 rabbits per group) after an experimental Achilles tendon rupture. The following treatment modalities were compared: a. operative functional treatment (resorbable suture, Kleinert technique) b. operative functional treatment with fibrin glue c. primary functional treatment. For the functional (after)-treatment a special orthosis was applied. A 7.5 MHz Ultrasound probe was used for the ultrasonographic evaluation. The histological specimens were stained after Masson-Goldner with Azan. Collagen Type III was depicted immunohistologically with polyclonal antibodies. A semiquantitative fibrocytes count was performed. The histological results showed a smooth healing in the prim. functional treatment group reaching parallel orientation of collagen fibers at 12 weeks. In the fibrin glue-group the fibrin was resorbed after 4 weeks without essential influence to the course of healing. In the suture-group a secondary gapping of the tendon stumps was detectable. At 12 weeks the histological evaluation in all groups showed approximately normal tendon pattern. Immunohistochemically all groups showed cell-associated positive reactions for type III-collagen after 1 week with a maximum after 2 weeks. The semiquantitative fibrocyte count in the primary funct. group showed a maximal number after 1 week, in the fibrin glue- and suture-groups the maximal number could be found after 2 weeks. Sonographically an increase in tendon thickness was detectable up to the 4th weeks in all groups. The secondary gapping of the tendon stumps in the suture group could be detected sonographically. The echogenicity of the tendon during the course of healing showed increasing homogeneity and parallelism in all groups. At 12 weeks the echogenicity was comparable in all groups. The experiment could prove the equivalence of the primary functional treatment to operative therapy in Achilles tendon rupture.

Achilles Tendon↗
PubMed1999

[Augmented tenoplasty in a case of tibialis anterior tendon rupture].

A tendon transfer or interposition tendon graft is usually recommended for treatment of late diagnosed ruptures of the tibial anterior tendon. A new operative technique using augmented tenoplasty is described in one patient. After 3 years the patient was asymptomatic and showed normalized function. The operative method has the advantage of no additional loss of function in comparison with other methods.

Adult↗
PubMed1999

Long-term results of subtalar fusions after operative versus nonoperative treatment of os calcis fractures.

From 1984 to 1994, 40 patients with a subtalar fusion were reexamined in long-term follow-up. The evaluation of the overall results was carried out with three different scoring systems. The calcaneal fractures were primarily treated nonsurgically in 23 patients (57.5%), and 17 patients (42.5%) had undergone ORIF. Complete pain relief was achieved in 52.5% of patients; 65% revealed a restriction in a range of motion in the ankle joint, and in 62% a grade 1 arthritis of the ankle joint was found. The statistical analysis could only reveal a tendency for a better outcome in the operative group compared with the nonsurgical group, although within the operated group, the majority of the os calcis fractures were more severe than in the nonsurgical group.

Adult↗