Subtalar dislocation is a rare injury caused by high-energy trauma. Current treatment strategies include leg casts, internal fixation and external fixation. Among these, external fixators are the most commonly used as this method is believed to provide better stabilization. However, the biomechanical stability provided by these fixators has not been demonstrated. This biomechanical study compares two commonly used external fixators, i.e. Mitkovic and Delta. CT imaging data were used to reconstruct three-dimensional models of the tibia, fibula, talus, calcaneus, navicular, cuboid, three cuneiforms and five metatarsal bones. The 3D models of the bones and cartilages were then converted into four-noded linear tetrahedral elements, whilst the ligaments were modelled with linear spring elements. Bones and cartilage were idealized as homogeneous, isotropic and linear. To simulate loading during walking, axial loading (70 N during the swing and 350 N during the stance phase) was applied at the end of diaphyseal tibia. The results demonstrate that the Mitkovic fixator produced greater displacement (peak 3.0mm and 15.6mm) compared to the Delta fixator (peak 0.8mm and 3.9 mm), in both the swing and stance phase, respectively. This study demonstrates that the Delta external fixator provides superior stability over the Mitkovic fixator. The Delta fixator may be more effective in treating subtalar dislocation.
Adequate pain relief is a requisite for a successful closed manipulative reduction (CMR) of fractures and dislocations. This prospective study was undertaken to assess the mode and adequacy of pain relief given to patients undergoing such procedures at Seremban Hospital from the 1st April to the 31st May 2001. All patients with fractures and dislocations scheduled to undergo CMR were included in this study. The type of sedative agents and analgesia administered were recorded. Demographic data and the type of fracture or dislocation of the selected patients were documented. A visual analogue scale (VAS) for pain perception was given to both to the patients and the medical personnel who performed the procedure. All data were collected manually before entered into computerized database for analysis. Of 72 patients included in this study, 47% were Malay, 26% Indian, 21% Chinese and 6% others. There was male predominance and the patients' age ranged between 9 to 79 years (average 27.4 years). Upper limb injuries (79%) were mainly fractures of the radius and ulna (29%) and isolated fracture radius (21%). For the lower limb injuries (21%), combined tibia and fibula fractures constituted 10% of the total cases followed by isolated tibia fractures (10%) and hip dislocation (1%). The most common pain relieving agents given during the CMR were intravenous pethidine alone (43%) followed by combination of intravenous pethidine and valium (36%), intramuscular pethidine (17%) and intramuscular tramal (4%). The Visual Analogue Score (VAS) for pain perception revealed that 61% of the patients had moderate pain while 21% had severe pain during the course of the procedures. Suboptimal pain relief administered during CMR should prompt positive actions to ensure that the patient is not subjected to undue pain just for the sake of an acceptable fracture reduction.
To study the long term result of open reduction of longstanding dislocated elbows with regard to stability, avascular necrosis of the distal humerus and degenerative changes of the joint.