In vitro antimicrobial activity of phramongkutklao hydroxyapatite antibiotic pellet.

OBJECTIVE: Assess the antimicrobial activity of Phramongkutklao antibiotic hydroxyapatite pellets in vitro. MATERIAL AND METHOD: The selected bacteria used in the present study were the standard and drug-resistant strains of Staphylococcus aureus and Pseudomonas aeruginosa, which are the common organisms causing infection in Orthopedics. Phramongkutklao antibiotic hydroxyapatite pellets developed by the Orthopedics Department, Phramongkutklao Hospital contained either Vancomycin, Fosfomycin, or Gentamycin. Each preparation was placed on an agar plate inoculated with each bacterium. The inhibition zones were monitored in 24 hours. Then the pellets were moved onto the new inoculated plate every day for 28 days. RESULTS: Compared with the control group, Phramongkutklao antibiotic hydroxyapatite pellets had good inhibitory effect against S.aureus. Vancomycin hydroxyapatite pellets were able to maintain their activity for 28 days whereas Gentamycin hydroxyapatite pellets was effective for only three days. Fosfomycin hydroxyapatite pellets could inhibit MSSA for 13 days and MRSA for 25 days. On the contrary, all three Phramongkutklao antibiotic hydroxyapatite pellets had very low efficacy against Paeruginosa. CONCLUSION: Phramongkutklao antibiotic hydroxyapatite pellets were able to inhibit the growth of S. aureus both MSSA and MRSA while the activity against P. aeruginosa needs to be developed.

Comparative study between computer assisted-navigation and conventional technique in minimally invasive surgery total knee arthroplasty, prospective control study.

BACKGROUND: Both Minimally Invasive surgery (MIS) and Computer-Assisted Surgery (CAS) are useful in Total Knee Arthroplasty (TKA). Minimally invasive total knee arthroplasty was associated with decreased blood loss, shorter hospital stays, and increased range of motion. Computer-assisted surgery in total knee arthroplasty was developed to improve the positioning of implants during surgery. OBJECTIVE: To evaluate radiographic results relative to component position and limb alignment when using a navigation system compared with conventional technique in MIS-TKA. MATERIAL AND METHOD: A prospective control study was performed in 180 patients who underwent total knee arthroplasty by one surgeon. All patients were randomly divided into two groups, Conventional and Navigation TKA. Intra-, post-operative data, and postoperative limb alignment were recorded for comparison in both groups. RESULTS: The postoperative mechanical axis was within 3 degrees of neutral mechanical alignment in 94% of the navigation group and 87% in conventional group (p = 0.13). Registration time of navigation group is 13.58 minutes. No statistical significant difference was found in tourniquet time and postoperative blood loss in both groups. CONCLUSION: The use of navigation in total knee arthroplasty increases accuracy in limb and implants alignment, and does not increase complications and surgical times.

Comparative study between 2 cm limited quadriceps exposure minimal invasive surgery and conventional total knee arthroplasty in quadriceps function: prospective randomized controlled trial.

OBJECTIVE: To compare the recovery time and straight leg raising test after total knee replacement between 2 cm limited quadriceps exposure minimally invasive surgery total knee replacement (2cm Quad MIS TKR) and conventional total knee replacement. MATERIAL AND METHOD: The authors conducted a randomized controlled trial in 40 osteoarthritis knee patients in two groups. Total replacement was performed by the same surgeon and the same prosthesis was used in each group. The function of Quadriceps muscle (straight leg raising test) range of motion was evaluated postoperatively. RESULTS: The 40 patients enrolled in the present study followed the complete study. After surgery with 2 cm Quad MIS TKA, quadriceps function recovery time was faster than with conventional total knee replacement. The quadriceps function was evaluated by the straight leg raising test (SLRT) in sitting and lay down position and the time of ambulation. CONCLUSION: Operative treatment with 2 cm Quad MIS TKA improved recovery time in quadriceps function when compared with conventional total knee replacement.

The prevalence of thrombophilia and venous thromboembolism in total knee arthroplasty.

BACKGROUND: Venous thromboembolism (VTE) is a common and potential serious complication in lower extremity surgeries, especially in hip and knee arthroplasty. Pulmonary embolism is one of the most fatal complications. The recognition of VTE in the lower limb has been considered as an indication for anticoagulation. Many studies have shown that thrombophilia is one factor of VTE and the most common causes are protein C, protein S and antithrombin III deficiency, factor V leiden and dysfibrinogenemia. VTE is a disease of Western populations because of well documentation of incidence and many studies about thrombophilia. In Thailand, the prevalence of VTE has been unclear. OBJECTIVE: The present prospective study evaluated the prevalence of thrombophilia and venous thromboembolism after total knee arthroplasty in patients who did not receive prophylactic treatment of VTE in Phramongkutklao Hospital. STUDY DESIGN: Descriptive prospective consecutive case studies. SETTING: The Department of Orthopedic Surgery, Phramongkutklao Hospital, Bangkok Thailand. MATERIAL AND METHOD: Blood sample was examined at 2-3 weeks before TKA for measuring the level of thrombophilia. Bilateral ascending contrast venography of the lower extremities was performed routinely between 6th-10th post operative days after total knee arthroplasty. RESULTS: The authors studied 100 patients, 94 primary TKA and 6 revisions TKA. Sixty-one (61%) were positive for deep vein thrombosis. Eleven patients with positive venograms showed bilateral DVT twelve (12%) had a proximal DVT one was protein C deficiency, nine were protein S deficiency, 18 were antithrombin III deficiency, and 36 were positive study for FDP(D-dimer), However, no one was found with factor V leiden. Odds ratio of protein S deficiency was 0.9506, Antithrombin III deficiency was 0.7376, and FDP(D-dimer) was 1.229. The protein C deficiency and factor V leiden was undetermined. CONCLUSION: Patients who have total knee arthroplasty performed are at high risk for deep venous thrombosis. Although fetal pulmonary embolism rarely occurs in Thai populations, mechanical prevention was routinely used and prophylactic regimen should be a part of management of patients who undergo total knee arthroplasty.

Risk factors of deep vein thrombosis (DVT) after total knee arthroplasty (TKA) at Phramongkutklao Hospital.

BACKGROUND: There have been sporadic reports on the Asian risk factor of DVT after total knee arthroplasty. OBJECTIVE: To determine the risk factors of DVT MATERIAL AND METHOD: Retrospective review of one hundred patients who had undergone TKA and postoperative Contrast Venography in bilateral legs between 2002 and 2005 were performed to identify risk factor of DVT The patients were divided into two groups, positive and negative venography which the patients who had positive venography were indicating the development to DVT RESULTS: One hundred patients were evaluated associated to DVT Eighteen of these patients were men, and eighty-two were women. The median age at the time of the procedure was seventy-five years old (range: 62 - 79 years old). Sixty-one patients showed positive venography for D VT Five critical risk factors were identified to develop DVT: 1. Underlying cardiovascular disease 2. Underlying hematological disease 3. Underlying rheumatoid arthritis 4. Patients who took oral herbal medicine about one year before the operation 5. Patients who received revision TKA. CONCLUSION: The risk factors of DVT in the presented patients at Phramongkotklo Hospital were similar to other countries. The research study could identify statistically significant risk factors and stimulate surgeons undertaking TKA to be aware of the probability of the patient to develop DVT.