In total knee arthroplasty, mechanical alignment guides have improved the accuracy of implant alignment, but errors are not uncommon. In the present study, an image-free computer-assisted navigation system was used to analyse the accuracy of an extramedullary (tibial) alignment system, which is based on predetermined, fixed anatomical landmarks. Comparisons were made between two surgeons, with different levels of competency in order to determine if experience affected the accuracy of extramedullary tibial jig placement, in either the coronal and sagittal planes or both planes. The results showed that the accuracy of the extramedullary tibial alignment system, in the coronal plane (in up to 80-87% of cases) was much better than for posterior slope, and sagittal plane. Surgeon experience was not a significant factor.
The PROSTALAC (PROSThesis Antibiotic Loaded Acrylic Cement) functional spacer is made with antibiotic-loaded acrylic cement. We use it as an interim spacer in two-stage exchange arthroplasty in cases of infected total knee or total hip replacement. PROSTALAC allows continuous rehabilitation between stages as it maintains good alignment and stability of the joint with a reasonable range of movement. It also helps to maintain the soft-tissue planes, thereby facilitating the second-stage procedure. We report here early outcomes of the use of PROSTALAC in 5 patients - 3 in total knee replacements, 1 in a total hip replacement and 1 in a bipolar hemiarthroplasty.
Necrotizing fasciitis is a life and limb threatening soft tissue infection with a high mortality rate. This study tries to identify the possible risk factors that contribute to mortality in patients with necrotizing fasciitis involving a lower limb. We prospectively reviewed 41 patients that presented with necrotizing fasciitis of the lower limb over a period of one year. Results show that the mortality rate for necrotizing fasciitis of the lower limb is quite high at 19.5%. Comparison among necrotizing fasciitis patients reveals that higher mortality rate is seen among those patients with advanced age and those presented with initial high pre-operative creatinine levels. Sex, pre-morbid diabetes mellitus, duration from initial symptoms to presentation for treatment and presence of streptococcus group A were not associated with an increased mortality rate. Neither were admission vital signs, subcutaneous gas on radiograph, prior antibiotic treatment on admission or clinical note of bullae formation.
A 27-year-old patient with ameloblastoma of the mandible
underwent anterior mandibulectomy and reconstruction with
left fibula osteocutaneous flap. The bone was shaped at the
lower limb before cutting the pedicle. Vascularised free fibula flap provides a good alternative to other bone grafts in mandible reconstruction as it is relatively easy to perform, carries a low complication rate, and mandibular shaping with intact pedicle cuts down on ischaemic as well as total operative time.
In comminuted patellar fractures, a combination of cerclage wiring and tension band fixation is said to provide good mechanical stability. This is a retrospective review of four patients treated with this method. All fractures described herein were classified as 45-C3 (based on Orthopaedic Trauma Association classification) and were fixed with a 1.25mm cerclage wire and tension band wire proximally looped through the quadriceps tendon and distally through the patellar ligament in a figure-of-eight configuration. The average follow-up period was 10 months. The Activity of Daily Living Scale (ADLS) of the Knee Outcome Survey was used to assess symptoms and functional capability of the knee. In all the cases, fracture union was achieved at an average of 11 weeks. The average ADLS score was good (92.5 %). Full range of knee motion was achieved by end of the third postoperative month. None of the patients had complications, such as infection and implant failure.
This retrospective radiographic analysis of 57 patients (62 knees) examined two possible factors involved in pin tract fractures of the femur due to navigated total knee arthroplasty (TKA): the angle of the tracker pin with respect to the lateral femoral cortex, and the distance between the tracker pin and the lateral joint line. Our findings demonstrate a relationship between postoperative pin tract induced stress fractures (3 patients), with pin tract angles exceeding 15°. Pin placement at a site more than 10cm from the lateral joint line, did not show any significant association with risk of fracture. These findings lead to enhanced understanding of the causative factors underlying pin track femoral fractures in TKAs.
Current available implants for total knee replacement are based on the mormphometry of the Caucasian knee. We believe there are significant morphometric differences in the Asian knee that will be relevant in future implant designs. Sixty-nine consecutive patients (80 knees) underwent computer navigated primary total knee arthroplasty. The anterior-posterior (AP) length, and the medial-lateral (ML) width of the distal femur, were analyzed, with respect to the final sizing details of four implants (femoral component) commonly used locally. The mean AP length was 59.9 (SD4.8) mm, and the mean ML width was 65.0 (SD 5.0) mm. The overall mean aspect ratio (ML/AP) was 1.09 (SD 0.07). The mean aspect ratio for females was 1.08 (SD 0.07). Both were smaller than the aspect ratio of the implants - which ranged from 1.11 to 1.13. All four implants tend to overhang at the medial-lateral width of the distal femur. This is more obvious in females. Future implant designs should provide more ML wdth sizes for a given AP length, in addition to gender differences, for this population.
This study was conducted to assess the optimum period for Kirschner wire fixation and cast immobilization for displaced lateral condylar fracture of the humerus in children. We retrospectively reviewed 12 patients with displaced lateral condyle humerus fracture, ranging in age from 3-9 y, with injuries that occurred between Jan 2005 and Dec 2006. All patients were treated with two Kirschner wire fixation and elbow immobilization. In all except 2 patients, the Kirschner wires were maintained for 3 to 4 weeks. Mean time for union was 3.78 weeks and mean humeroulnar arch motion at last review was 138.7 degrees. Only one patient had a 5 degree increased carrying angle in valgus as compared to the non-injured side, and 50% had prominent scars > 4mm. We conclude that fracture union can be expected within three to four weeks for most children after open reduction and fixation with 2 Kirschner wires.