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R Hertel

Publications and source records attributed to R Hertel.

At least 37 records · Page 2Linked to original sources

On the timing of soft-tissue reconstruction for open fractures of the lower leg.

The timing of soft-tissue reconstruction for severe open fractures of the lower leg is considered crucial to the later outcome, and yet pertinent publications are few. The purpose of this study was to add some based on evidence arguments for the choice of the most adequate timing in the management of these injuries. Twenty-nine consecutive open fractures of the tibia, including 24 grade 3B and 5 grade 3C fractures, were treated using a protocol of immediate debridement, early definitive skeletal stabilisation and early soft-tissue reconstruction. Fifteen lower legs were reconstructed after a mean delay of 4.4 days (range 1-9 days), while 14 lower legs were reconstructed immediately, i.e. as an emergency procedure on the day of admission. Both groups were comparable for sex, age, type of trauma, associated general injuries, type of fracture, associated arterial lesion, associated tendon rupture, type of soft-tissue reconstruction and duration of follow-up. All patients were reviewed at a mean follow-up of 47 months (range 15-89 months). In the delayed reconstruction group the time to full, unprotected weight-bearing (P = 0.0021), the time to definitive union (P = 0.0049), the number of reoperations (P = 0.0001) and the infection rate (P = 0.0374) were significantly higher. The data suggest that immediate reconstruction is, the general condition of the patient permitting, the timing of choice for soft-tissue coverage.

Adolescent↗

TrkB and neurotrophin-4 are important for development and maintenance of sympathetic preganglionic neurons innervating the adrenal medulla.

The adrenal medulla receives its major presynaptic input from sympathetic preganglionic neurons that are located in the intermediolateral (IML) column of the thoracic spinal cord. The neurotrophic factor concept would predict that these IML neurons receive trophic support from chromaffin cells in the adrenal medulla. We show here that adrenal chromaffin cells in the adult rat store neurotrophin (NT)-4, but do not synthesize or store detectable levels of BDNF or NT-3, respectively. Preganglionic neurons to the adrenal medulla identified by retrograde tracing with fast blue or Fluoro-Gold (FG) express TrkB mRNA. After unilateral destruction of the adrenal medulla, 24% of IML neurons, i.e., all neurons that are preganglionic to the adrenal medulla in spinal cord segments T7-T10, disappear. Administration of NT-4 in gelfoams (6 microgram) implanted into the medullectomized adrenal gland rescued all preganglionic neurons as evidenced by their presence after 4 weeks. NT-3 and cytochrome C were not effective. The action of NT-4 is accompanied by massive sprouting of axons in the vicinity of the NT-4 source as monitored by staining for acetylcholinesterase and synaptophysin immunoreactivity, suggesting that NT-4 may enlarge the terminal field of preganglionic nerves and enhance their access to trophic factors. Analysis of TrkB-deficient mice revealed degenerative changes in axon terminals on chromaffin cells. Furthermore, numbers of FG-labeled IML neurons in spinal cord segments T7-T10 of NT-4-deficient adult mice were significantly reduced. These data are consistent with the notion that NT-4 from chromaffin cells operates through TrkB receptors to regulate development and maintenance of the preganglionic innervation of the adrenal medulla.

Adrenal Medulla↗

[Complex trauma of the shoulder girdle].

Complex injuries of the shoulder require differentiated management. Interestingly there is a relative lag of warranted information on this subject. Generally the different lesions are discussed separately. However it is not acceptable to simply add the standard diagnostic and therapeutic measures, because major tactic, strategic and rehabilitation incompatibilities could occur. Diagnostic and therapeutic difficulties are frequent for the following injuries: complex proximal humerus dislocation fractures, dislocation fractures with associated lesions of the rotator cuff, posterior dislocation fractures, peri- and intraarticular segmental fractures and fractures or dislocations associated with major neurovascular lesions. Increased awareness of the most relevant diagnostic and therapeutic aspects should contribute to optimize treatment protocols.

Fracture Fixation, Internal↗

[Missed compartment syndrome after anterior cruciate ligament-plasty following continuous peridural anesthesia].

In this article we report a case of an early postoperative compartment syndrome of the anterior tibial compartment with complete sensomotoric palsy of the peroneal nerve after arthroscopic-assisted replacement of the anterior cruciate ligament (ACL) of the knee. The tourniquet pressure was 360 mm Hg and operation time was 1.75 h. After the operation the leg was bandaged to avoid swelling of the leg and as antithrombotic prophylaxis. Analgesic therapy was by continuous epidural bupivacaine infusion. Increasing pain of the lower leg was suppressed by additional analgesia. Due to persistent pain despite regular analgesia, the patient was sent to a main hospital on the 3rd postoperative day, where an extremely painful and swollen anterior tibial compartment with intracompartmental pressure of over 100 mm Hg was found. The compartment was released immediately. Despite the appearance of severe muscle damage, no extensive débridement was done. At the second examination, at 48 h, there was minimal perfusion of the muscles without contraction and islands of ischemic necrosis. Clinically, there was complete palsy of the dorsiflexors of the foot. The case shows the danger of a compartment syndrome when tourniquet of the limb, arthroscopy and a firm bandage are combined. Continuous epidural analgesia masks the classic symptoms of compartment syndrome.

Adult↗

[Management of IIIB open tibial fractures by early osteosynthesis and local muscle flap].

From 1986 to 1994 18 patients with 19 IIIB open tibial fractures were treated following similar therapeutic management. This included early and radical primary debridement, early and wherever possible immediate internal fixation of the bone and coverage with a local muscle flap (hemisoleus or gastrocnemius). At the time of follow-up all fractures had consolidated clinically as well as radiographically. The mean time to bony union was 7 months (3-20). Twelve patients did not have any severe pain and were able to walk for more than 4 km. The time to return to work averaged 8 months. In 2 cases a permanent disability of 50% was established. Fourteen of 18 patients were satisfied with the function of the leg. On the other hand, 9 didn't like the aesthetic appearance and were inhibited because of it. The following complications occurred within a period of 2 years: non-union (3), flap necrosis (2), osteomyelitis (2), delayed union (4). The mean number of reoperations was 3 (0-8). In no case did an amputation have to be performed.

Adult↗

[Indications and results of shoulder prosthetics in complex proximal humerus fractures].

Complex fractures of the proximal humerus are uncommon injuries and a therapeutic challenge to the orthopaedic surgeon. Successful treatment requires proper evaluation of the patient and analysis of standardized high-quality radiographs. The trauma series of radiographs (including true anteroposterior and lateral views in the scapular plane, and axillary view) is essential for accurate fracture assessment. Generally, joint-preserving reconstructive techniques are emphasized, aiming at restoration of the anatomy of the proximal humerus. In young individuals with excellent quality of the bone fragments, careful techniques of reduction and fixation, avoiding additional surgical devascularization, should be performed, even in case of possible impairment of the vascular supply to the humeral head. In elderly individuals with osteoporotic bone and limited compliance throughout aftercare, humeral head replacement may be indicated less restrictively. In the latter group hemiarthoplasty generally can be expected to result in painfree shoulders. However, recovery of function and range of motion are much less predictable.

Adult↗

Plate osteosynthesis of diaphyseal fractures of the radius and ulna.

Between January 1980 and December 1989, 133 consecutive patients were treated for a fracture of the shaft of one or both forearm bones (134 forearms in total). All fractures were stabilized with AO/ASIF 3.5 mm stainless-steel dynamic compression plates. The 1 year follow-up rate was 99 per cent; the long-term follow-up rate was 92 per cent (the mean long-term follow-up was 10.2 years (range, 2.7-15.2)) so there were 96 men and 35 women, with an average age of 37.5 years (range, 16-63). Twenty-two per cent of the forearms had open fractures, 26 per cent of patients had sustained multiple injuries and 19 per cent had a head injury. One hundred and twenty-seven of 132 forearms (96.2 per cent) underwent problem-free consolidation before 6 months. Two delayed unions and two non-unions required reoperation. There was one superficial infection in a patient with a closed fracture. Plates were removed from 70 patients (53 per cent) at a mean of 33.1 months (range, 8-122) after the first operation. In this group, there were three refractures (4.3 per cent) occurring at a mean of 8.7 months (range, 0-14) after plate removal. This study confirms the safety and efficacy of plate osteosynthesis in forearm shaft fractures: a high union rate and low complication rate can be anticipated. The data presented form the most reliable information on this subject currently available with the longest and highest rate of follow up of a sufficient number of patients using a single implant system in a single institution.

Adolescent↗

Amputation versus reconstruction in traumatic defects of the leg: outcome and costs.

This retrospective review covers global aspects of reconstructive efforts to salvage severely injured legs. Eighteen patients with traumatic lower leg amputation were compared to 21 patients who underwent complex microvascular reconstruction. The mean number of interventions was 3.5 for amputation and 8 for reconstruction (p < 0.009). Total rehabilitation time was 12 months for amputation and 30 months for reconstruction (p < 0.009). Changes in lifestyle were consistently more important in the amputee group. The mean annual hospital costs for amputated patients were 15,112 Swiss Francs (SD 7,094 SF) for the first 4 years. The mean annual hospital costs for reconstructed patients were 17,365 Swiss Francs (SD 8,702 SF) for the first 4 years. Fifty-six percent of the amputees and 19% of the reconstructed patients were retrained to a different profession (p < 0.025). Fifty-four percent of the amputees and 16% of the reconstructed patients were drawing an extremely costly and life long invalidity pension (p < 0.02). We conclude that for potentially salvageable legs reconstruction is advisable because the functional outcome was better than for amputation and there was no permanent social disintegration due to the long treatment. Total costs (including pensions) for reconstruction were far lower than for amputation.

Adolescent↗

Thermal necrosis after tibial reaming for intramedullary nail fixation. A report of three cases.

We present three young men who sustained closed diaphyseal fracture of the tibia and later developed severe osteocutaneous necrosis induced by heat during intramedullary reaming. They all had a narrow medullary cavity and in all a tourniquet had been used. Each developed a pretibial cutaneous blister soon after operation. In the following month severe osteomyelitis ensued, requiring segmental resection and osteocutaneous reconstruction.

Adolescent↗

Use of the ipsilateral vascularised fibula for tibial reconstruction.

Between 1989 and 1994 we used a vascularised ipsilateral fibular graft in 24 patients with segmental tibial defects. We report 12 patients with a minimum follow-up of two years. The graft was either transposed medially or inverted on its vascular pedicle. Full weight-bearing was achieved at between four and seven months. We had few complications and consider that the use of this method is a valuable option in reconstruction of the tibia.

Adult↗

Cancellous bone graft for skeletal reconstruction. Muscular versus periosteal bed--preliminary report.

The purpose of this project was to verify the value of perfused periosteum as a possibly ideal bed for autogenous cancellous bone graft. The model consisted of a 7 cm defect in the sheep tibia, stabilized with a locked intramedullary nail. The defect was filled with conventional cortico-cancellous bone graft covered either with a muscle or a perfused osteoperiosteal flap. The incorporation of the graft was analysed by a series of radiological and mechanical examinations. The graft embedded in perfused osteo-periosteum was rapidly remodelled to a strong, circular bone. Mechanical testing revealed even better values than for normal bone. The graft embedded in muscle showed an important resorptive phase before scanty, incomplete, reconstitution of bone appeared. Mechanical properties were poor. The study supports the hypothesis that perfused osteo-periosteum is an ideal bed for cancellous bone graft and that perfused muscle is not the ideal environment for incorporation of the graft.

Animals↗

Double vascularized fibulas for reconstruction of large tibial defects.

Vascularized fibular grafts have proven to have many advantages over nonvascularized transplants for treatment of large segmental bone defects in the extremities. Fibulas are typically impacted into the medullary canal and fixed with wires or screws. Consolidation has often been delayed and full weightbearing was only possible after graft hypertrophy, usually 12 to 18 months after reconstruction. In order to shorten the time of consolidation and to achieve early full weightbearing, the authors propose a sound biomechanical reconstructive concept: a) stable but not devascularizing osteosynthesis of the osteotomy to shorten the time of consolidation; b) a double-strut fibular graft that yields enough strength for early weightbearing, without the need for bone hypertrophy; and c) additional cancellous bone grafts, to enhance the long-term stability of the reconstruction. Seven patients with tibial defects ranging between 6 and 17.5 cm were treated according to this concept. In four cases, free vascularized fibula was transferred first. Six weeks later, a vascularized, ipsilateral fibula-pro-tibia procedure was done, and the space between the fibulas was filled with cancellous bone grafts. In three patients, a free, vascularized, double-barrel, fibula transfer was done, since the tibial defect was less than 10 cm. Cancellous bone grafts between the fibulas were added only 6 weeks later. In five cases, the free fibula transfer was combined with a latissimus dorsi myocutaneous flap. In six patients, healing was uneventful. In one patient, hypoperfusion of the lower extremity and the vascularized grafts eventually resulted in a below-knee amputation. In all six successful cases, union resulted within 3 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗