***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: OBJECTIVE To determine the value of using a closed-suction drain in cemented knee arthroplasty . METHODS One hundred patients were prospect ively r and omized into two groups , one group underwent cemented total knee replacement with a single deep closed-suction drain , and the other group ( n = 50 )  no drain . RESULTS The total blood loss was significantly greater in those with a drain although those without lost more blood into the dressings . There was no statistical difference in the postoperative swelling or pain score , ecchymosis , deep vein thromboses ( DVT ) , time at which flexion was regained or the incidence of infection at a minimum of two years after surgery in the two groups . CONCLUSION There is no evidence to support the use of a closed-suction drain in cemented knee arthroplasty OBJECTIVE To compare the impact of rehabilitative process of placing drainage versus no drainage during total knee arthroplasty ( TKA ) . METHOD A prospect i ve study was performed in 30 osteoarthritic patients who underwent one-stage bilateral TKA between October 2007 and December 2008 . For every patient , drainage was r and omly placed intra-operatively only on one knee side . Pain VAS scores , extremity swelling , incision healing , recovery of knee joint flexion and extension function and early postoperative complications were compared statistically as a self-control study . RESULTS All patients were followed up for at least one month . Comparing drainage side with non-drainage side , the mean pain VAS scores at Day 3 post-operation were 4.7 + /- 1.8 and 4 . 9 + /- 1.9 respectively ; the mean extremity swelling differences of supra patellar ( infra patellar ) perimeter at Day 6 post-operation were 1.8 + /- 1.7 ( 0.7 + /- 1.0 ) cm and 1.7 + /- 1.3 ( 1.0 + /- 1.0 ) cm respectively ; the mean flexion ( extension ) differences at Day 30 post-operation were 12.5 + /- 21.6 ( 4.4 + /- 6.9 ) degrees and 11.7 + /- 23.9 ( 4.2 + /- 6.4 ) degrees respectively . There was no obvious statistical difference between placing drainage and no drainage in all the above aspects ( paired t-test , P > 0.05 ) . There was also no statistical difference of early postoperative complications between two groups ( exact Fisher test , P > 0.05 ) . CONCLUSION For unsophisticated TKA , placing drainage had no effect upon reducing the pain , extremity swelling and incision exudation . It also had no effect upon reducing the incidence of hematoma to prevent early infections and promoting rehabilitation . Comparing with no drainage , placing drainage had no obvious advantage . On the contrary , it might complicate the surgical steps and increase the chances of post-operative hemorrhage and retro grade infections . Thus no drainage is recommended in such a kind of operation In a prospect i ve study we analyzed the volume of drainage , the contamination of the drain track , and drain tip in 81 primary total hip arthroplasties in 78 patients . The drain was removed when the drainage from midnight to the following morning was 20 mL or less . The drainage in the first 12 h and in total was reduced in cases with a drain period of 24 h , compared to cases with a drain period of 48 and 72 h. 4 cases had a positive culture from the wound before closure . 5 cases had a positive culture from the tip of the drain , and 6 from the drain track . The most frequently isolated microorganism was coagulase-negative Staphylococcus . The positive cultures from the drain track and tip were not correlated to the duration of drainage . 68 drains were removed within 48 h with no risk of developing wound complications We prospect ively r and omised 78 patients into two groups , ' drains ' or ' no drains ' to assess the effectiveness of suction drains in reducing haematoma and effusion in the joint and its effect on wound healing after total knee replacement . Ultrasound was used to measure the formation of haematoma and effusion on the fourth post-operative day . This was a semi-quantitative assessment of volume estimation . There was no difference in the mean effusion between the groups ( 5.91 mm in the drain group versus 6.08 mm in the no-drain , p = 0.82 ) . The mean amount of haematoma in the no-drain group was greater ( 11.07 mm versus 8.41 mm , p = 0.03 ) . However , this was not clinical ly significant judged by the lack of difference in the mean reduction in the post-operative haemoglobin between the groups ( drain group 3.4 g/dl ; no-drain group 3.0 g/dl , p = 0.38 ) . There were no cases of wound infection or problems with wound healing at six weeks in any patient . Our findings indicate that drains do not reduce joint effusion but do reduce haematoma formation . They have no effect on wound healing We studied the management of postoperative drainage after total knee replacement ( TKR ) . 90 primary total knee joint arthroplasties were prospect ively r and omized into 3 groups : a ) no drain , b ) an autotransfusion system , c ) a st and ard disposable closed suction drainage system . We monitored hemoglobin and hematocrit values , drainage volume and transfusions ( homologous and autologous ) , range of knee motion , knee swelling and hospital stay . Parameters were recorded preoperatively , days 0 - 8 and 4 months postoperatively . No significant differences were seen between the groups in any of the parameters measured . The results show no benefit from using postoperative drainage systems in knee arthroplasties . Savings of SEK 400 ( USD 55 ) per patient would have result ed if drains had not been used at all Abstract . Sixty patients were operated on for primary gonarthrosis by means of a cemented , posterior cruciate preserving total knee  and were r and omly allocated to postoperative drainage or nondrainage . The primary criterion was duration of hospital stay . Secondary criteria included serial evaluation of knee pain , knee flexion , knee circumference , calculated blood loss after 7 days , complications , reoperations , and the need for blood transfusions . There was no difference between the two groups in any of the criteria during the entire follow-up . There was a nonsignificant trend to a decreased calculated blood loss in the nondrained group and significantly less transfused blood units in the nondrained group . Lack of drainage does not increase complication risk after total knee prosthesis implantation . We therefore recommend using no routine drainage after this procedure OBJECTIVE To prospect ively compare of no drain or with drain after unilateral total knee arthroplasty ( TKA ) . METHODS A r and omized prospect i ve study was conducted between February 2006 and February 2007 . The study included 100 patients who were divided into 2 groups : group A ( n = 50 ) , which included patients without drain release , and group B ( n = 50 ) , which included patients who had a drain release .  The true total blood loss was calculated depending on the height , body mass and pre- and post-operative Hct , and hidden blood loss was gotten by subtracting the visible blood loss from total loss . The recovery after surgery , the correlative complications and transfusion amounts were compared and analyzed . RESULTS All 100 patients undergoing TKA were involved in the result analysis . In patients without a drain , the total blood loss was ( 535 + /- 295 ) ml and the hidden blood loss was ( 513 + /- 290 ) ml , in patients with a drain , the total blood loss was ( 853 + /- 331 ) ml and the hidden blood loss ( 689 + /- 324 ) ml . The total and hidden blood loss , blood transfusion amount between drain-group and without drain-group was significantly different ( P < 0.05 ) . The difference in the incidence of infection and post-op recovery and correlative complications did not reach statistical significance . CONCLUSIONS In patients having primary TKA , using a drain , compared with no use of a drain , does not show us a clear advantage that make us accept it . Without a drain release could present an effective and economic method for reducing blood loss and preventing blood transfusion in patients undergoing unilateral TKA We prospect ively r and omised 100 patients undergoing cemented total knee replacement to receive either a single deep closed-suction drain or no drain . The total blood loss was significantly greater in those with a drain ( 568 ml versus 119 ml , p < 0.01 ; 95 % CI 360 to 520 ) although those without lost more blood into the dressings ( 55 ml versus 119 ml , p < 0.01 ; 95 % CI -70 to 10 ) . There was no statistical difference in the postoperative swelling or pain score , or in the incidence of pyrexia , ecchymosis , time at which flexion was regained or the need for manipulation , or in the incidence of infection at a minimum of five years after surgery in the two groups . We have been unable to provide evidence to support the use of a closed-suction drain in cemented knee arthroplasty . It merely interferes with mobilisation and complicates nursing . Reinfusion drains may , however , prove to be beneficial A prospect i ve investigation was design ed to determine the volume and the evolution of bleeding  after closure of the surgical wound following knee arthroplasty , as well as the incidence of infection and bacterial contamination in relation with the time that the suction drain was left in place . The drain was removed either 12 , 24 or 48 hours after the operation . The presence of any signs of clinical infection was recorded . The tip of the drain , 1 cm of its subcutaneous portion and a sample from the collecting bottle were studied for bacterial contamination . In the 12-hr group , no microorganisms were isolated in cultures either from the tip , the subcutaneous portion or the bottle of the drain . In the 24-hr group , 87 % of the total postoperative bleeding was collected during the first 12 hours . In two cases , the sample s obtained from the tip and the subcutaneous portion of the drain were positive for Staphylococcus epidermidis . In the 48-hr group , 91 % and 97 % of the total bleeding volume was collected during the first 12 and 24 hours , respectively . In two cases , St. epidermidis was isolated in cultures from the subcutaneous portion of the drain . The clinical evaluation of wound healing was comparable in all three groups OBJECTIVE To identify risk factors associated with the development of surgical-site infection ( SSI )  following total knee arthroplasty ( TKA ) . DESIGN A case-control study . SETTING A 1,100-bed , university-affiliated , tertiary-care teaching hospital . METHODS Case- patients with SSI occurring up to 1 year following primary TKA performed between January 1999 and December 2001 were identified prospect ively by infection control practitioners using National Nosocomial Infections Surveillance ( NNIS ) System methods . Three control- patients were selected for each case-patient , matched by date of surgery . Stepwise logistic regression analysis was used to determine the relation of potential risk factors to the development of infection . RESULTS Twenty-two patients with infections ( 6 superficial and 16 deep ) were identified .  Infection rates per year were 0.95 % , 1.07 % , and 1.19 % in 1999 , 2000 , and 2001 , respectively . Logistic regression analysis identified two variables independently associated with the development of infection : the use of closed suction drainage  ( odds ratio [ OR ] , 7.0 ; 95 % confidence interval [ CI95 ] , 2.1 - 25.0 ; P = .0015 ) and increased international normalized ratio ( INR ) ( OR , 2.4 ; CI95 , 1.1 - 5.7 ; P = .035 ) . Factors not statistically associated with the development of infection included age , NNIS System risk index score , presence of various comorbidities , surgeon , duration of procedure or tourniquet time , type of bone cement or prosthesis used , or receipt of blood product transfusions . CONCLUSIONS The use of closed suction drainage and a high postoperative INR were associated with the development of SSI following TKA . Avoiding the use of surgical drains and careful monitoring of anticoagulant prophylaxis in patients undergoing TKA should reduce the risk of infection A prospect i ve study of 69 patients ( 138 knees ) who had a primary simultaneous bilateral total knee replacement was conducted to assess the effect of postoperative suction drainage on wound healing and infection . A suction drain was placed by r and omization of side for the drained versus nondrained side . The same operative technique was used in all wounds of total knee arthroplasty . The knees that had no drains had a higher incidence of drainage from the wound , had soaked dressings requiring dressing reinforcements , and had more ecchymosis and erythema around the wound . However , the final results regarding quadriceps strength , range of motion , and wound complications were not affected significantly by nonuse of closed suction drainage . Although the incidence of infection in the two groups is not statistically different , the 
    Output:
    
Conclusion The finding raises the possibility that drains are not required to assist in recovery following TKA