New Technique for Reducing Blood Loss in Total Knee Arthroplasty

A prospective randomised study was carried out to evaluate the blood loss in 30 total knee arthropasty patients, who were divided randomly into two equal groups; one having new technique bone plug and bone wax, while the other used a bone plug only. The surgery was carried out by a single surgeon at one institution using the uniform approach and standard operation. The mean drainage of blood was lower in the bone plug and bone wax group. This difference was statistically significant (p=0.001). There was a highly significant reduction in blood drainage in the bone plug and bone wax group when compared to the bone plug only group. This finding allows for the order of less blood before an operation, reduces the risks of transfusion and gives financial saving. This new technique of surgery may also be useful for patients in whom blood products are not acceptable. Chiang Mai Medical Journal 2007; 46(4):147-152. Total knee arthroplasty (TKA) is a common orthopedic surgery that can result in considerable blood loss.(1,2) Many techniques and procedures have been used to minimize intra-operative bleeding and blood transfusion, including application of a tourniquet,(3) minimally-invasive surgery,(4) diathermy coagulation, sealing of the intramedullary femoral canal,(5) positioning of the knee(6) and use of antifibrinolytic agents.(7) Although computer navigation has been developed to allow accurate intra-operative positioning of the components, without breaching the intra-medullary cavities(8) but providing an opportunity for reducing blood loss, it can prolong the operating time, as commonly occurs in computer-assisted surgery, and this may negate the benefit This study was carried out as a prospective, randomized study to evaluate the new technique of bone plug and bone wax in comparison to the standard conventional surgical technique, in terms of reducing blood loss during TKA. Patients and methods This study was carried out in all patients who underwent TKA at Phayao Hospital between 21 February 2006 and 3 July 2007. Patients were randomly allocated to one of two 148 Anan Malairungsakul Figure 1. Bone from cutting part of distal femer (piece 1). groups from sealed envelopes. There were 15 patients in each group. In group I, both bone plug and bone wax were used, whereas, bone plug only was used in group II. A standardized technique of TKA was used in all patients with the same instruments (Johnson and Johnson Cemented fixed bearing type). Intra-operative and post-operative blood lost were recorded by the surgeon from the volume of blood in the suction bottle and the estimated blood loss in the qauze. All patients received spinal anesthesia, and none received thromboprophylaxis. Blood transfusion was given only in patients who had a postoperative hematocrit of less than 30 vol%. Operative technique and prosthesis The operations were performed using the same surgical approach, instrumentation and technique. The operations were carried out with blood loss fluid using a pneumatic tourniquet at a pressure of 400 mmHg after exsanguinations. The new technique applied a bone plug in the distal femoral hole (to guide the femoral out) and bone wax on the cutting surface outside the femoral and tibia implants. Whereas, the standard technique applied the bone plug only. New technique for bone plug and bone wax The bone plug was harvested from the cutting part of the distal femur (as shown in Fig. 1, 2, and 5) to seal the femeral hole site of the intra-medullary alignment guides, and the second piece (as shown in Fig.3 and 4) was sealed on top of the first one (as shown in Fig. 6) before the prosthesis was applied. Bone wax was used on the cut cancellous bone surface around the prosthesis in both the femeral and tibial part (as shown in Fig. 7 and 8). The bone only plug group The bone plug was harvested from the cutting part of the distal femur (as shown in Fig. 1,2 and 5) to seal the femoral hole site of the intra-medullary alignment guides, and the second piece (as shown in Fig. 3 and 4) was sealed on top of the first one (as shown in Fig. 6) before the prosthesis was applied. Figure 2. After recut to bone plug (piece 1). New technique for reducing blood loss in to tal knee arthoplasty 149 Figure 3. Bone from cutting part of distal femer (piece 2). Figure 4. After recut to bone plug (piece 2). Figure 5. Bone plug piece 1 sealed femeral hole. Figure 6. Bone plug piece 2 sealed on top the piece 1. Figure 7. Bone wax was used in cut cancellous bone surface in femeral part. Figure 8. Bone wax was used in cut cancellous bone surface in tibial part. 150 Anan Malairungsakul Statistical analysis Continuous variables were presented as mean ± standard deviation (SD). Categorical variables were presented in percent. Student’s t-test was used for statistical analysis. A twotailed p value of < 0.05 was considered a statistically significant difference. Results Of the 30 patients studied, 6 males and 24 females had a mean age of 59.2 years (range 53 -72). All patients were matched for age, gender, and preoperative hematocrit level (Table 1). The mean total blood loss during the operation was 80.0 + 26.3 ml. (range 50150) in group I, and 147.0+ 98.2 mL (range 50-200) in group II (= 0.095). However, the mean total blood loss in the drainage bottle was 326.0+125.3 ml. (180-440) in group I and 757.0+248.8 mL. (500-1200) in group II (p < 0.001). The mean total blood loss during the operation and in the drainage bottle was 406.0 + 186.3 ml. (500-1,200) in group I, and 904+125.8 mL. (180–440) in group II (p < 0.001). One patient in group II received 1 unit of blood transfusion (blood loss 1200 ml, Hct 28%). Discussion The amount of blood loss during cemented total knee arthroplasty varied among different reported studies. In this study, we tried to minimize blood loss during surgery by applying a tourniquet, using minimal invasive surgery (MIS), giving transamic acid and using computer assisted surgery. However, the major site of bleeding generally came from the distal femeral hole and sinusoids at the cut cancellous bone surfaces.(10,11) In this study, we found that the new technique of using bone plug and bone wax significantly reduced blood loss when compared with the conventional technique, which used a bone plug only when applying cemented implant suction drains for 24 hours and immediate continuous passive movement. The mean blood loss in the drains in this study was lower than that of 1,500 mL in a previous report.(9) However, the mean blood loss during the operation was no different between the two groups, because of the tourniquet effect. Bleeding from sinusoids at the cut cancellous bone surfaces had significant volume. No patients in group I required blood transfusion, but one patient in group II did. Conclusion The new technique of using a bone plug in the femoral hole and bone wax on the cut cancellous bone surfaces in cemented TKA significantly reduced blood loss when compared with the group that used a bone plug only. New technique for reducing blood loss in to tal knee arthoplasty 151