To assess the outcome of knee “arthrodesis” using cemented Endo-Model knee fusion nail in failed Total Knee Replacement (TKR) with significant bone loss due to infection. This is a retrospective case study of seven patients with infected TKR and multiple surgeries with significant bone loss. All patients had antibiotic loaded cement with a temporary K-nail as a first stage procedure to eradicate infection. All seven patients had “arthrodesis” performed using cemented modular Endo-Model Knee Fusion nail (Waldemar Link, Hamburg) by the senior author. Cement was used to hold the stems in the diaphyses and not used around the coupling mechanism. The “arthrodesis” relied entirely on the coupling mechanism which has been shown to have good axial and torsional rigidity by mechanical testing. Outcome was assessed using pre and post Visual Analogue Score (VAS). Mean age was 72.3 years(62–86). Mean follow up was 39.6 months (7–68). The VAS pain score improved from pre-operative mean score of 7.9 to a postoperative score of 1.5. One patient suffered fracture of femoral cement mantle at 50 months who underwent a technically easy exchange revision. One patient had recurrent infection with distal femoral fracture at 36 months and was revised to distal femoral replacement. The Endo-Model knee arthrodesis nail restores limb lengths, has good early results in terms of pain relief and provides a stable knee “arthrodesis” in cases where there is significant bone loss and extensor mechanism insufficiency following an infected TKR.
Most hospitals have introduced digital radiography (PACS) systems. Accurate pre-operative templating prior to hip arthroplasty requires precise information on the magnification of the digital image. Without this information the benefits of expensive digital templating programs (Orthoview-£10000) cannot be realised. To determine the magnification of a digital image involves the placement of a “calibration object” at the level of the hip joint. This is unpopular with patients and radiographers alike. We describe a method that requires a single measurement to be made from the greater trochanter to the digital film. An AP pelvis x-ray was taken of 50 patients with hip replacements. The “predicted” magnification was calculated using the new method. As the size of the head of the prosthesis was known the “actual” magnification could be calculated also. There was no significant difference at 0.05, Wilcoxon T, 2-tail test. Conventional radiography, which assumes a magnification of 20%, results in errors up to 11%. Templating may therefore predict an incorrectly sized prosthesis. Our method is as accurate as methods using a calibration object whilst being acceptable to patients and staff. Its use should lead to more accurate pre-operative templating prior to total hip arthroplasty
Aprotinin has been shown to reduce blood loss in a number of surgical specialities. Patients with Duchenne Muscular Dystrophy (DMD) bleed more during surgical procedures than patients without this condition. The aim of this study was to evaluate the effect of aprotinin in reducing blood loss in scoliosis correction surgery in patients with DMD. A retrospective analysis of case notes was performed. Thirty two patients diagnosed with DMD who underwent surgical correction for scoliosis over the last 25 years were included. All patients underwent posterior spinal fusion and instrumentation, between the levels T3 and L3. All procedures were carried out by the same lead surgeon. Patient age, body weight, length of procedure, and estimated blood loss were recorded. Blood loss as a percentage of total circulating volume was calculated and compared between patients who had not received aprotinin (seven patients), and those who did (25 patients). Blood loss as a percentage of total circulating volume in the group of patients with aprotinin (range 37% – 107% mean 67%) was significantly lower (P<
0.05) than the group without aprotinin (range 67% – 157% mean 111%). There was found to be no statistically significant relationship between blood loss and length of procedure. There was no statistically significant difference in the duration of the procedure between the two groups of patients. Despite the small number of patients this study shows a beneficial effect for aprotinin in reducing blood loss during scoliosis correction surgery in patients with DMD.