We report here a rare presentation of an extra-nodal non-Hodgkin's lymphoma. Both clinical presentation radiological findings were suggestive of psoas abscess. Surgical debridement was performed and histopathological examination of the tissue sample revealed the diagnosis of non-Hodgkin's lymphoma. It is therefore important to note that non-Hodgkin's lymphoma can mimic psoas abscess and that psoas lesion with vertebral involvement does not necessarily indicate infection. It is always advisable to obtain needle biopsy to establish diagnosis before embarking on surgical intervention. The practice to send any suspicious tissue obtained intra-operatively for histopathological examination is also warranted.
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.
A 20- year-old female student was involved in a motor vehicle accident. She sustained a severe friction injury to the left knee that resulted in considerable soft tissue and bone loss. There was also damage to the knee extensor mechanism, tibialis anterior muscle, femoral trochlea, the anterior half of the tibial plateau extending distally to the proximal tibia and skin. However, there was no crushing of the limb or resultant neurovascular deficit but cancellous bone and the remainder of the joint were exposed. Repeated surgical debridement was performed and was followed by covering of the soft tissue using a latissimus dorsi free flap and skin grafts. The bony defect was reconstituted with antibiotic bone cement to prevent flap adherence and shrinkage, enhance stability and prevent fracture. The cement was later removed at the time of arthrodesis at which time an ipsilateral double barrel vascularised fibular graft supplemented with autogenously cancellous bone and a ring fixator was used. Computer tomography confirmed union at three months post procedure. The fixator was then removed and a tibialis posterior transfer was performed.
Interlocked intramedullary nailing is accepted as the gold standard for femoral shaft fractures. However for Winquist type I and II femoral fractures at the isthmus region, unlocked intramedullary nailing (Küntscher nailing) is still a good option. We performed a retrospective study on 86 patients with a total of 88 femoral shaft fractures around the isthmus that presented at our institution between 1 January 1988 and 31 August 2003. All patients (84.1% Winquist type I and 15.9% Winquist Type II fractures) were treated with unlocked intramedullary nail. The average time to union was 16 weeks with 97.7% rate of union. There were two cases (2.3%) of infection and non-union each. Overall results were comparable to standard interlocking intramedullary nailing. We conclude that unlocked intramedullary nailing is a good treatment option for Winquist Type I and II femoral fracture around the isthmus with its good union rate and minimal complications.
Freeze drying is a dehydration method to dry bone under freezing environment, enabling removal of water
with no or minimial effects on bone strength and durability. Larger size bones obviously require longer freeze
drying time to reduce water content to the required level for long term storage at room temperature. For small
size bone cubes or chips, it is a normal practice to pool cortical and cancellous bones for freeze drying. The
study was aimed at determining if different type of bones of the same size influence the drying time. Human
bone cubes of 10 mm x 10 mm x 10 mm were prepared from cortical bone of tibiae and cancellous bone from
femoral heads. The bone cubes were freeze dried to reduce water content to less than 6%. Moisture content
was monitored using gravimetric method.Weight and density of cortical bone were significantly higher than
cancellous bone despite of having similar small size (p