Minimally invasive plate osteosynthesis of distal fractures of the tibia.

Minimally invasive plate osteosynthesis of distal tibial fractures is technically feasible and may be advantageous in that it minimizes soft tissue compromise and devascularization of the fracture fragments. The technique involves open reduction and internal fixation of the associated fibular fracture when present, followed by temporary external fixation of the tibia until swelling has resolved. Subsequent limited, but open reduction and internal fixation of the articular fragments when displaced followed by minimally invasive plate osteosynthesis of the tibia utilizing precontoured tubular plates and percutaneously placed cortical screws is performed. The semitubular plate was chosen because it adapts more easily to the bone contours than the stiffer small fragment LC-DCP does. Twenty patients (age 25-59 years) with unstable intraarticular or open extraarticular fractures have been treated including 12 A-type, 1 B-type and 7 C-type fractures according to the AO classification. Two fractures were open (both Gustilo Type I). Closed soft tissue injury was graded according to Tscherne with 3 type C0, 7 type C1, 7 type C2 and 1 type C3. All fractures healed without the need for a second operation. Time to full weight-bearing averaged 10.7 weeks (range 8-16 weeks). Two fractures healed with > 5 degrees varus alignment and 2 fractures healed with > 10 degrees recurvatum. No patient had a deep infection. The average range of motion in the ankle for dorsiflexion was 14 degrees (range 0-30 degrees) and plantar flexion averaged 42 degrees (range 20-50 degrees). With longer follow-up and a larger number of patients, the authors feel confident that the minimally invasive technique for plate osteosynthesis for the treatment of distal tibial fractures will prove to be a feasible and worthwhile method of stabilization while avoiding the severe complications associated with the more standard methods of internal or external fixation of those fractures.

Combined Monteggia and Galeazzi fractures in a child's forearm. A case report.

We report the occurrence of a previously undescribed combined Monteggia and Galeazzi fracture pattern of the left forearm in an 8-year-old boy. Previous reports do not address the combined injury described in this article, which consists of a left radius shaft fracture with dislocation of the distal radioulnar joint, and a left ulna shaft fracture with anterior dislocation of the radiohumeral joint. An excellent result was obtained with closed reduction. Radiographic evaluation is crucial in these disorders for both diagnosis and for treatment decisions. A review of the literature is provided with specific emphasis toward the classifications, mechanisms of injury, diagnosis, associated injuries, and treatment.

Effects of acetylcholine and substance P on electrical activity of intact toad gastric muscles.

By using isolated gastric muscle cells of Bufo marinus, others have studied the mechanism of action of muscarinic agonists and substance P (SP). To compare responses of isolated cells with those of intact muscles, we have studied the effects of acetylcholine (ACh) and SP on membrane potentials of circular muscle cells in strips of intact muscle from the toad gastric corpus region. These cells had average resting potentials of -69 +/- 0.7 mV. Membrane potential rhythmically depolarized, producing slow waves at an average frequency of 1/min and average amplitude of 25 +/- 2.2 mV. The major effect of ACh (10(-7) to 10(-4) M) was chronotropic; the frequency of slow waves was increased by 88 +/- 11% by 10(-6) M ACh. The amplitudes and rates of rise of slow waves were decreased by ACh. SP had effects similar to ACh; its major effect was chronotropic. The data suggest that ACh and SP primarily affect the pacemaker mechanism in gastric muscles. Since rhythmicity is apparently not expressed in isolated gastric myocytes, it is possible that this effect of these agonists may have been missed in studies of dispersed cells. Our data suggest that the excitatory effects of ACh and SP on contractions may be due to summation of Ca2+ signals, a partial tetanus-like effect.