Treatment of Bone Defect with Modular Metal Augmentation Using a Downsized Block in Total Knee Arthroplasty: Technical Note and Report of 17 Cases

In total knee arthroplasty (TKA), a treatment of bone defect varies depending on the location and extent of defect and requires proper surgical procedure. Metal augmentation is readily available for both femoral and tibial bone defects. We report the operative technique of modular metal augmentation using a downsized block for ambiguous proximal tibial and distal femoral bone defects in primary and revision TKA. Regarding bone defects, bone loss can be minimized by using a different size of metal augmentation, and suitable reinforcement for bone defects can be achieved. Once our technique is properly used, it will be very helpful in treating bone defects.

Comparison of Clinical Results in Deep Vein Thrombosis of Total Knee Arthroplasty with Rivaroxaban and Dalteparin Sodium

This study was intended to investigate into the incidence rates of deep vein thrombosis (DVT) in patients who used prophylactic antithrombotic medications after total knee arthroplasty (TKA), and to compare clinical results in groups treated with Rivaroxaban versus Dalteparin sodium as prophylactic antithrombotic medications. This prospective study was performed in 300 patients who underwent TKA between November 2011 and December 2012. The prophylactic therapy was given to 150 patients in Rivaroxaban group and Dalteparin sodium group, respectively. In addition, intermittent compression pump and stocking were used in all the groups immediately after TKA. In order to determine the incidence of DVT, color Doppler ultrasonography, D-dimer, and clinical symptom examination were conducted. There were 17 cases (11.3%) of DVT in Rivaroxaban group and 18 cases (12.0%) of DVT in Dalteparin sodium group after TKA, and no significant difference was seen between both groups. Between patients with DVT and those without DVT after TKA at 4 days in both groups, there was a significant difference in the swelling indices. Moreover, a significant difference was observed in the evaluation of bruise. The early signs of DVT after TKA are unknown, however, some initial clinical signs such as swelling have been observed. After using the said prophylactic drugs, the lower incidence of DVT was seen, and there was no difference between the types of drugs. Pharmacological therapy (either Rivaroxaban or Dalteparin sodium) after TKA is considered effective for DVT prevention. There is also a need to consider constant monitoring of clinical symptoms.

Mucoid Degeneration of Posterior Cruciate Ligament Leads to Roof Impingement with Anterior Cruciate Ligament: Case Report

Mucoid degeneration of cruciate ligament is rare cause of knee pain, however there are some cases causing pain and restriction of extension. A 60-year-old man came to our clinic complaining of pain in knee joint on full range of extension about 3 months ago. The range of motion (ROM) was a flexion contracture of 5 degree and a further flexion of 140 degree with pain aggravation by forced extension. Magnetic resonance imaging of the knee joint showed thickened posterior cruciate ligament (PCL) mucoid degeneration. Arthroscopic treatment consists of PCL reduction-plasty by debridement of yellowish material in the PCL fiber and reduces the volume of the hypertrophied PCL. Immediately after surgery, patient gain the full ROM without any symptom of impingement. Enlarged PCL can make impingement in femoral notch with anterior cruciate ligament (ACL). Then, Partial debulking surgery of PCL is an effective treatment to pain relief and restore ROM of knee.

The Clinical Characteristics of Combined Deep Vein Thrombosis Prophylaxis of Rivaroxaban and Mechanical Therapy after Total Knee Replacement Arthroplasty

Purpose: To investigate the clinical characteristics of combined prophylaxis of rivaroxaban (Xarelto?) and mechanical therapy (foot sole pump, antiembolism stocking) after total knee replacement arthroplasty, for prevention of deep vein thrombosis (DVT). Materials and Methods: The subjects of this study were 110 patients who underwent total knee replacement arthroplasty (TKA) between November 2011 and May 2012, and were prospectively evaluated. They consisted of 13 men (11.8%) and 97 women (88.2%) with the mean age of 68.7 years (±7.9). All of the patients received 10 mg of rivaroxaban once daily for 14 days from Day 1 postoperatively, and used an intermittent pneumatic compression (IPC) pump and compression stockings immediately after the operation. To determine the presence of postoperative DVT, clinical symptoms examination, D-dimer test, color Doppler ultrasound imaging were performed to analyze the risk factors of DVT events. Results: There were a total of 13 patients (11.8%) with DVT in the distal lower limbs among the entire 110 patients. At Day 4 after the operation, a statistically significant difference was seen only in femoral swelling of several clinical symptoms between DVT group and non-DVT group (p = 0.043). D-dimer tests showed no statistically significant difference between the two groups, however with the boundary value of 0.3 mg/L, diagnostic sensitivity, specificity, positive predictability and negative predictability were equivalent to 100%, 8.2%, 12.7% and 100%, respectively. There was no significant difference between the two groups in terms of well-known risk factors including age, gender, obesity, hypertension, diabetes, smoking, and anesthesia method, and no case of pulmonary embolism was observed. Conclusion: A combination of pharmacological therapy (rivaroxaban, Xarelto?) and mechanical therapy (foot sole pump system) after TKA is considered effective for DVT prevention.

Medial Patella Subluxation after Minor Trauma

Most cases of medial patella subluxation occur under iatrogenic conditions that are often associated with a prior excessive lateral retinacular release procedure. We report a case of medial subluxation following minor trauma with no history of previous lateral release. The abnormality was identified on magnetic resonance imaging and was successfully treated by direct repair of the lateral retinaculum. The recognition and treatment of medial subluxation of the patella without retinacular release can be difficult. Therefore, consideration of multiple causes through careful medical history taking, physical examination, and radiologic examination is needed for accurate diagnosis.