Pneumatic compression device does not show effective thromboprophylaxis following total knee arthroplasty in a low incidence population.

INTRODUCTION: Purpose of this study was to assess whether the intermittent pneumatic compression (IPC) device would be an effective prophylaxis for deep vein thrombosis (DVT) following total knee arthroplasty (TKA) in a low incidence population. HYPOTHESIS: The mechanical thromboprophylaxis could reduce the incidence of DVT compared to non-prophylaxis group and would have similar efficacy as the chemoprophylaxis following TKA in a low DVT incidence population. MATERIALS AND METHODS: From January 2009 to June 2016, 1259 elective primary TKA with preoperative diagnosis of primary osteoarthritis in a single institute were enrolled. Patients were divided into three groups: those who were managed with chemoprophylaxis (CPX group, 414 cases), with mechanical prophylaxis (IPC group, 425 cases), or without pharmacological and mechanical prophylaxis (control group, 420 cases). All patients underwent preoperative ultrasonography and computed tomographic venography on postoperative day 6 to assess development of DVT. The incidence of overall, proximal, symptomatic DVT and symptomatic pulmonary embolism (PE) were compared among the groups. Major and minor bleeding complications were also evaluated. RESULTS: The incidence of overall DVT was 14.8% in control group, 6.3% in CPX group and 11.3% in IPC group respectively and CPX group showed significantly lower incidence than other two groups (p<0.001). The incidence of proximal DVT was 1.9% in control group, 0.7% in CPX group and 0.9% in IPC group respectively (p>0.05). The incidence of symptomatic DVT was 0.7% in control group, 0% in CPX group and 0.7% in IPC group respectively (p>0.05). There was no case of symptomatic PE diagnosed during hospital stay in all patients. DISCUSSION: Single use of IPC device could not reach significant level of DVT prophylaxis compared to control group and only chemoprophylaxis showed significantly reduce the incidence of overall DVT following TKA. Single use of IPC device does not show effective thromboprophylaxis in a low DVT incidence population. LEVEL OF EVIDENCE: III, case control study.

Medial Open-Wedge High Tibial Osteotomy May Adversely Affect the Patellofemoral Joint.

PURPOSE: To evaluate 2-stage arthroscopic findings of the patellofemoral joint before and after medial open-wedge high tibial osteotomy (HTO) and verify whether the patellofemoral joint would be influenced by medial open-wedge HTO. METHODS: We prospectively reviewed 114 cases of medial open-wedge HTO for the treatment of osteoarthritis with a varus knee. First-look arthroscopy was performed during HTO. The mean age at the time of HTO was 56.34 ± 5.4 years (range, 40-69 years). Second-look arthroscopy was performed concomitantly with plate removal at an average of 26.1 ± 6.0 months (range, 21.6-32.0 months) after HTO. We assessed the patellofemoral joint using the International Cartilage Repair Society (ICRS) grading system by first- and second-look arthroscopy and compared it before and after HTO. Postoperative anterior knee pain was also evaluated. RESULTS: Compared with first-look findings, second-look arthroscopic ICRS grading was changed as follows: In terms of the patella, 89 cases (78.1%) were not progressed whereas 25 cases (21.9%) were progressed. In terms of the femoral trochlea, 67 cases (58.8%) were not progressed whereas 47 cases (41.2%) were progressed. There was significant progression of the ICRS grade of the patella (P = .001) and femoral trochlea (P < .001) compared with first-look arthroscopic findings. The incidence of postoperative anterior knee pain was 11.4% (13 cases), and it was related to the ICRS grade of the patellofemoral joint at the time of second-look arthroscopy (P < .001 for patella and P < .001 for trochlea). CONCLUSIONS: This study showed that the patellofemoral joint might be adversely affected by medial open-wedge HTO. Although the incidence of postoperative anterior knee pain was low, it was clinically correlated with patellofemoral arthritis. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Are Korean Patients Different from Other Ethnic Groups in Total Knee Arthroplasty?

Most of the implants used for total knee arthroplasty (TKA) in Asian patients have been produced based on anthropometry of Western people. Since anatomic features and life styles are different between Western and Eastern people, there would be ethnic differences in terms of conformity of implants to the patient's anatomy or clinical results after TKA. Therefore, surgeons in Asia are particularly interested in related surgical techniques and implant designs used in TKA for improved clinical results and patient satisfaction. In this review, we investigated the anthropometric differences of Koreans from Westerners. Koreans are of shorter stature, less weight, and smaller skeletal structure and have a higher incidence of constitutional varus alignment of the lower extremity. Moreover, compared to Westerner TKA populations, the proportion of female patients was large and primary osteoarthritis was prevalent in preoperative diagnosis in Korean TKA patients. Culturally, Koreans have life styles that demand high flexion positions of the knee such as squatting, kneeling, and cross-legged sitting. Although there were no notable differences in the complication and revision rates following TKA between Westerners and Koreans, the incidence of postoperative deep vein thrombosis and pulmonary thromboembolism was lower in Koreans than Westerners. We hope that further research on implant designs and more interest in TKA will improve outcomes in Korean patients.

Is Single-Radius Design Better for Quadriceps Recovery in Total Knee Arthroplasty?

PURPOSE: Although single-radius (SR) designs have a theoretical advantage in quadriceps recovery following total knee arthroplasty (TKA), there has been a paucity of objective evaluation studies. MATERIALS AND METHODS: One hundred and twenty minimally invasive TKAs were prospectively randomized by a single surgeon into 2 groups: SR design TKA group and multi-radius design TKA group. Quadriceps force and power were assessed using a dynamometer, and clinical data were investigated preoperatively and 6 weeks, 3 months, 6 months and 1 year postoperatively. RESULTS: There were no differences between two groups in quadriceps recovery and clinical results throughout the follow-up period. Furthermore, the proportion of patients whose postoperative quadriceps force and power reached preoperative level was similar in both groups. CONCLUSIONS: Femoral component design itself would not significantly influence quadriceps recovery after TKA.

Characterization of a CK II protein kinase from etiolated oat seedlings.

Protein kinases play a central role in controlling the cellular metabolism of living organisms. A protein kinase was purified from etiolated oat seedlings by several steps of ion-exchange and affinity chromatographies. The kinase was a 150-kDa tetrameric protein and composed of three subunits of 34, 37, and 40 kDa proteins. The 34 and 40 kDa proteins had ATP binding sites, suggesting that they are catalytic subunits and that the 37-kDa protein is a regulatory subunit. In the in vitro phosphorylation of a crude oat cell extract, it intensively phosphorylated a serine residue of a 110-kDa protein. The 110-kDa protein was tentatively identified as a DNA topoisomerase I, based on an amino acid sequence homology. Phosphorylation of the 110-kDa protein by the kinase required ATP or GTP as a phosphoryl group donor. The kinase activity was inhibited by 50% at a concentration of 0.05 microg/ml heparin. These results, therefore, indicate that the purified kinase is a CK II protein kinase and may be involved in the regulation of DNA topoisomerase I activity.