Aims

Osteosarcoma is the most common primary bone malignancy among children and adolescents. We investigated whether benzamil, an amiloride analogue and sodium-calcium exchange blocker, may exhibit therapeutic potential for osteosarcoma in vitro.

Components from 73 failed knee replacements (TKRs) consisting of rotating-platform, mobile-bearing and fixed-bearing implants were examined to assess the patterns of wear. The patterns were divided into low-grade (burnishing, abrasion and cold flow) and high-grade (scratching, pitting/metal embedding and delamination) to assess the severity of the wear of polyethylene.

The rotating-platform group had a higher incidence of low-grade wear on the upper surface compared with the fixed-bearing group. By contrast, high-grade wear comprising scratching, pitting and third-body embedding was seen on the lower surface. Linear regression analysis showed a significant correlation of the wear scores between the upper and lower surfaces of the tibial insert (R² = 0.29, p = 0.04) for the rotating-platform group, but no significant correlation was found for the fixed-bearing counterpart.

This suggests that high-grade wear patterns on the upper surface are reduced with the rotating-platform design. However, the incidence of burnishing, pitting/third-body embedding and scratching wear patterns on the lower surface was higher compared with that in the fixed-bearing knee.

Of 37 consecutive patients suffering from tuberculosis of the lumbosacral spine, 26 were reviewed after an average follow-up of 20 years. Those presenting at under 10 years of age usually had a discharging sinus or a pointing abscess and a visible kyphosis. In older patients, low back pain was the predominant presenting symptom. Neurological involvement was uncommon. Both operative and conservative treatment had resulted in fusion but all patients treated conservatively ended up with a kyphosis associated with trunk shortening. They had a higher incidence of back pain and more complications in pregnancy. Anterior debridement and fusion with a strut graft can reduce the incidence and size of kyphosis, but is technically demanding. Treatment remains difficult and requires individual consideration.

We reviewed 20 adult patients with spondylolysis and isthmic spondylolisthesis an average of 10.5 years after treatment by anterior spinal fusion. Nineteen patients had excellent or satisfactory results. Ten of the patients were symptom-free at one year, and 15 were asymptomatic at final follow-up. Anterior spinal fusion can produce results comparable to those of posterior fusion with or without decompression. The results tend to improve with time in contrast to the known worsening of late results after posterior decompression without fusion.

Twenty-two patients with late onset Pott's paraplegia presenting at a mean of 18 years after initial symptoms were reviewed an average of seven years after treatment by anterior decompression and fusion. Fourteen patients had active disease, and in 12 of these, activity at the internal kyphus was the direct cause of the paraplegia. In the other two, a soft healing bony ridge was the cause. The eight patients with healed disease had hard bony ridges compressing the cord. The response to anterior decompression was faster, better and safer in patients with active disease: nine recovered completely and three significantly. In patients with healed disease, the anterior decompression was technically more difficult and the recovery less satisfactory. Significant complications included two cases with neurological deterioration, two with cerebrospinal fluid fistulae and four with neurapraxia of the cord.

We reviewed 40 cementless Porous Coated Anatomic knee replacements in 34 consecutive patients. The average follow-up was 12.9 months (range 6 to 36 months). At review, loose beads were identified in 23 knees, in 11 on the femoral side and in 16 on the tibial side (in five knees on both sides). One loose bead was adjacent to the patella. In four knees there were intra-articular beads. Radiolucent lines at the interface between bone and prosthesis were seen in 19 knees, in six on the femoral side and in 16 on the tibial side (in three knees on both sides). In relation to the tibial component loose beads were associated with a radiolucent line in all except one case. Progressive loosening with an increasing number of loose beads was seen in three knees. At this early stage of follow-up there was no correlation between the clinical results and the presence of loose beads.