Reduced capacity of whole blood leucocytes to express tumour necrosis factor-alpha and interleukin-10 following major orthopaedic surgery.

BACKGROUND: Severe trauma is a challenge to the immune response and may cause reduced immune capacity. As a marker of decreased cellular activity, studies with ex vivo lipopolysaccharide (LPS) stimulation of whole blood or isolated mononuclear cells from injured patients have revealed reduced production of inflammatory cytokines. To gain further insight into immune alterations in orthopaedic surgery, we studied LPS-induced tumour necrosis factor (TNF)-alpha and interleukin (IL)-10 in whole blood of patients during peri- and postoperative phases of total hip replacement. METHODS: Four females and 3 males undergoing elective total hip replacement were included in the study. Ex vivo LPS-induced TNF-alpha and IL-10 were measured in a whole blood assay before, during and at 1 and 6 days after operation. In addition, the counts of white blood cells were determined. RESULTS: During the operation, there were significant reductions in the number of monocytes, but at day 1 and 6 after surgery, there were significant increases as compared to the levels before surgery. The capacity of whole blood to express TNF-alpha and IL-10 did not change significantly during the operation and the following postoperative day. At day 6, however, there were significant reductions in expression of both TNF-alpha and IL-10 as compared to the levels before the operation. In relation to the values of monocytes, there was a significant reduction in the expression of TNF-alpha also at day 1 after operation. CONCLUSION: Our data indicate that in the course of at least 6 days after a major orthopaedic trauma, there is suppression of the whole blood capacity to express the inflammatory cytokine TNF-alpha and the anti-inflammatory cytokine IL-10 when exposed to LPS. During this time, then, the patient is particular susceptible to septic complications.

Effects of macrophage activation on bone healing.

In this study the effect of macrophage activation on bone healing was investigated in rats. In three groups of rats, an osteotomy of the femoral bone was performed and then nailed. Macrophages were activated by semisoluble aminated glucan. In one group of animals this was applied locally, in another group it was applied systemically (intraperitoneally), and the third group served as control. Eight rats in each group were killed after 4, 8, and 12 weeks, and the mechanical characteristics of the healing osteotomies were evaluated. We found that local activation of macrophages induced an immature hypertrophic callus with reduced biomechanical characteristics, as evaluated by bending moment, rigidity, and energy absorption. There were no significant differences between the rats subjected to systemic macrophage activation and the control rats. We conclude that local macrophage activation during the initial phase of bone repair impairs healing.

Allografting in uncemented acetabular revision.

From 1987 to 1991, a total of 43 acetabular revisions were performed in 39 patients aged 36 to 79 years. In group A (26 revisions in 24 patients), morselized allograft was used to fill in cavitary acetabular defects, and in group B (17 revisions in 15 patients), a solid (bulk) allograft was used to reconstruct defects of the acetabular rim, mainly superiorly. An uncemented acetabular cup was used in all cases. Follow-up ranged from 4 to 7 years. Results demonstrated that while large structural or morselized allografts are useful in reconstructing the anatomy, there is a high rate of loosening due to resorption. The failure rate of bulk graft was higher than that of morselized graft, but because the bone stock in failures is usually restored, a second revision is easier.

Effects of ketoralac tromethamine and indomethacin on primary and secondary bone healing. An experimental study in rats.

Ketoralac tromethamine is a new non-steroidal anti-inflammatory drug that is being used extensively as an analgesic in orthopaedic surgery, particularly for outpatient procedures. However, as with all non-steroidal anti-inflammatory drugs there have been theoretical concerns about the effect of the drug with regard to bone metabolism and healing. In the present study bone healing of femoral osteotomies was evaluated in rats given ketoralac tromethamine in comparison with two other groups of rats given indomethacin and saline (control group), respectively. Under unstable healing conditions, 3 days of medication with indomethacin significantly reduced the femoral bending moment, bending rigidity and energy expenditure compared with the control group. Such impairment of mechanical characteristics was not found during the first 3 days after osteotomy in rats given ketoralac tromethamine. There were no significant differences in mechanical properties between the three groups when healing occurred under stable conditions. Ketoralac tromethamine is a rather new NSAID that has excellent aqueous solubility and lacks tissue irritability [2]. It is, therefore, very suitable for parenteral use. Additionally, it is the most potent NSAID known, equal or superior to morphine for pain relief following orthopaedic surgery [9]. Its use has therefore become widespread as an alternative to opioid analgesics [7]. Its effects on bone metabolism and healing have, however, not been fully elucidated, and concern has been expressed about its potential effect. The present study was designed to investigate the effects of short-term administration of ketoralac tromethamine on bone healing under stable and unstable conditions in rats, as compared to indomethacin.

Femoral shortening in total arthroplasty for completely dislocated hips: 3-7 year results in 25 cases.

During the years 1988-1991, we performed 25 total hip replacements for completely dislocated hips in 15 women and 4 men with a median age of 54 (17-67) years. In all cases, femoral shortening at the subtrochanteric level was performed to obtain reduction of the hip. The patients have been followed for 3-7 years. 1 patient experienced sciatic nerve palsy, 1 a delayed union and 1 a malunion at the osteotomy site. There were no signs of mechanical failure. All patients were satisfied. According to the Charnley hip score, function was excellent in 15 cases, good in 9 and fair in 1. The median Harris hip score improved from 43 at the time of operation to 93 at follow-up. 7 hips had a positive and 18 a negative Trendelenburg test. Before operation, all patients had a Trendelenburg limp. Our intermediate results indicate that femoral shortening at the subtrochanteric level is a suitable adjunct to total arthroplasty for a completely dislocated hip.

Good prognosis for low back pain when left untampered. A randomized clinical trial.

OBJECTIVE: This randomized clinical trial was designed to determine the effect of treating low back pain as a benign, self limiting condition by light normal activity. METHODS: Patients on sickness leave from work for more than 8 weeks were randomized into two groups: intervention (n = 463) and control (n = 512). Those in the intervention group were examined, provided information, and given instruction. Outcome was measured by return or failure to return to work (still on sickness leave). RESULTS: Survival analysis showed a highly significant (P = 0.000) reduction in sickness leave in the intervention group as compared with the control group. At 200 days 60% were still on sickness leave in the control group vs. 30% in the intervention group. A multivariate analysis with age, sex, and treatment as cofactors showed that sex had no effect on length of sickness leave and that treatment retained its effect when adjusting for differences in age composition. CONCLUSION: This study indicates that low back pain treated as a benign, self limiting condition recommended to light mobilization gives superior results as compared to treatment within a conventional medical system.