Dae-Cheol Nam

Revision Total Knee Arthroplasty with a Cemented Posterior Stabilized, Condylar Constrained or Fully Constrained Prosthesis: A Minimum 2-year Follow-up Analysis

Background The clinical and radiological outcomes of revision total knee arthroplasty with a cemented posterior stabilized (PS), condylar constrained knee (CCK) or a fully constrained rotating hinge knee (RHK) prosthesis were evaluated. Methods This study reviewed the clinical and radiological results of 36 revision total knee arthroplasties with a cemented PS, CCK, and RHK prosthesis in 8, 25, and 13 cases, respectively, performed between 1998 and 2006. The mean follow-up period was 30 months (range, 24 to 100 months). The reason for the revision was aseptic loosening of one or both components in 15, an infected total knee in 18 and a periprosthetic fracture in 3 knees. The average age of the patients at the time of the revision was 65 years (range, 58 to 83 years). The original diagnosis for all primary total knee arthroplasties was osteoarthritis except for one case of a Charcot joint. All revision prostheses were fixed with cement. The bone deficiencies were grafted with a cancellous allograft in the contained defect and cortical allograft fixed with a plate and screws in the noncontained defect. A medial gastrocnemius flap was needed to cover the wound dehiscence in 6 of the 18 infected cases. Results The mean Knee Society knee score improved from 28 (range, 5 to 43) to 83 (range, 55 to 94), (p < 0.001) and the mean Knee Society function score improved from 42 (range, 10 to 66) to 82 (range, 60 to 95), (p < 0.001) at the final follow-up. Good or excellent outcomes were obtained in 82% of knees. There were 5 complications (an extensor mechanism rupture in 3 and recurrence of infection in 2 cases). Three cases of an extensor mechanism defect (two ruptures of ligamentum patellae and one patellectomy) were managed by the RHK prosthesis to provide locking stability in the heel strike and push off phases, and two cases of recurrent infection used an antibiotic impregnated cement spacer. The radiological tibiofemoral alignment improved from 1.7° varus to 3.0° valgus in average. Radiolucent lines were observed in 18% of the knees without progressive osteolysis. Conclusions Revision total knee requires a more constrained prosthesis than primary total knee arthroplasty because of the ligamentous instability and bony defect. This short to midterm follow-up analysis demonstrated that a well planned and precisely executed revision can reduce pain and improve the knee function significantly. Infected cases showed as good a result as those with aseptic loosening through the use of antibiotics-impregnated cement beads and proper soft tissue coverage with a medial gastrocnemius flap.

Use of Intramedullary Nonvascularized Fibular Graft with External Fixation for Revisional Charcot Ankle Fusion: A Case Report

We describe a case of Charcot ankle arthropathy in a 43-year-old male patient who underwent revision surgery for tibiotalocalcaneal arthrodesis with a retrograde intramedullary nonvascularized fibular graft. After 3 months of postoperative stabilization with a ring external fixator, successful radiographic union was identified. The findings obtained at 33 months postoperatively showed maintenance of solid fusion and restoration of hindfoot alignment without any complications.

The value of diagnostic ultrasonography in the assessment of a glomus tumor of the subcutaneous layer of the forearm mimicking a hemangioma: a case report

IntroductionA glomus tumor is a rare, benign tumor with atypical clinical symptoms. Because of its small size, it is difficult to diagnose and treat early; therefore, it leads to poor quality of life. Glomus tumors are known to commonly affect the hand and rarely manifest in other areas. Because they simulate neuromas, hemangiomas, and neurofibromatosis, the differential diagnosis is difficult. We performed marginal resection of a solitary forearm mass previously suspected to be a hemangioma or glomus tumor on the basis of ultrasound findings and histologically diagnosed to be a glomus tumor afterward. We report this case to demonstrate the good prognosis of the procedure we used, and we review the relevant literature.Case presentationA 68-year-old Asian man without a particular medical history visited our hospital with a mass with focal tenderness in his left distal forearm that had developed 8 years earlier. The tumor was observed with suspicion of being a hemangioma or glomus tumor based on the location, clinical symptoms, and ultrasound findings taken into consideration together. The biopsy results led us to conclude that the lesion was a glomus tumor.ConclusionsA glomus tumor located in the forearm is very rare. It is often clinically overlooked and is likely to be misdiagnosed as another disease. The patient’s quality of life deteriorates, and, though the disease is rare, it has serious sequelae. Therefore, a quick diagnosis and appropriate treatment must be conducted early. If a mass occurs with serious pain in subcutaneous soft tissue of not the hands but the limbs, it is important to conduct examinations with suspicion of a glomus tumor. Ultrasonography performed quickly may be useful for making the differential diagnosis.

A Review of the Literature on Culture-Negative Periprosthetic Joint Infection: Epidemiology, Diagnosis and Treatment

Purpose The prevalence of periprosthetic joint infection (PJI) has increased with the increasing incidence of arthroplasty surgery. Considering identification of causative microorganisms is crucial for treatment of PJI, culture-negative (CN) PJI is a significant clinical issue. The purpose of the present study is to describe epidemiology, diagnosis and treatment of CN PJI based on review of the literature to help prevent delayed diagnosis and improve clinical outcomes of CN PJI. Methods MEDLINE, EMBASE, Cochrane Library and Scopus databases were searched for articles on CN PJI. Only clinical studies written in English were included. Basic science studies, letters to the editor, case reports and review articles on PJI were excluded. Results Seven studies were included in this study. The prevalence of CN PJI ranged from 0% to 42.1%. The major risk factors for CN PJI were prior antibiotic use and presence of postoperative wound drainage. Vancomycin and cephalosporins were the most commonly used antibiotics for CN PJI. Two-stage revision arthroplasty followed by 6 weeks of antibiotic therapy produced the most successful treatment outcomes. Conclusions In most clinical studies on CN PJI, a definite diagnostic method for identifying causative microorganisms or optimal treatment strategy for CN PJI were not clearly described. Therefore, further studies are needed to establish standard diagnostic methods for identifying infecting organisms and treatment strategies for CN PJI.

The role of isolated posterior cruciate ligament reconstruction in knees with combined posterior cruciate ligament and posterolateral complex injury

PurposeThis is a meta-analysis comparing biomechanical outcomes to determine whether an isolated posterior cruciate ligament (PCL) reconstruction can restore normal knee kinematics in a combined PCL/posterolateral complex (PLC) injury and whether double-bundle (DB) PCL reconstruction is superior in controlling posterior and rotational laxity compared with single-bundle (SB) PCL reconstruction in a PCL/PLC-deficient knee.MethodsA number of electronic databases were searched for relevant articles published through August 2016 that compared biomechanical outcomes of PCL reconstruction in patients who underwent reconstruction for combined PCL/PLC deficiencies. Data were searched, extracted, analysed, and assessed for quality according to Cochrane Collaboration guidelines, and biomechanical outcomes were evaluated using various outcome values. The results are presented as relative ratios for binary outcomes and standard mean differences for continuous outcomes with 95% confidence intervals.ResultsFive biomechanical studies were included in this meta-analysis. There were significant differences in laxities such as posterior tibial translation (PTT), external rotation, varus rotation, and PTT coupled with external rotation in the isolated PCL reconstruction group compared with the native PCL group. Furthermore, there were no significant differences in laxities such as PTT, external rotation, or varus rotation between the SB and DB PCL reconstruction groups.ConclusionIsolated PCL reconstruction, whether SB or DB, could not restore normal knee kinematics in the PCL/PLC-deficient knee. In such cases, residual laxity after isolated PCL reconstruction can be controlled successfully with PLC reconstruction. Therefore, simultaneous PCL and PLC reconstruction is recommended for patients with combined PCL/PLC injury.

Monostotic fibrous dysplasia in the proximal tibial epiphysis: a case report

IntroductionFibrous dysplasia is one of many well-known disorders in which there is a defect in the remodeling process of immature bone to mature into lamellar bone, and it often exists in metaphyseal and diaphyseal parts of the long bone. In this report, we describe a rare case where fibrous dysplasia was found only in the proximal part of the epiphysis of the tibia without other bony lesions.Case presentationA 14-year-old Asian girl was referred to our hospital after slipping down with pain on the left knee. A radiograph showed an abnormal finding of a central radiolucent lesion with a marginal sclerotic border near the proximal tibial spine. A magnetic resonance image showed the lesion at low signal intensity on a T1-weighted image and at high signal intensity on a T2-weighted image. The biopsy results led us to conclude that the lesion was a fibrous dysplasia.ConclusionIf an abnormal lesion on the epiphysis, especially in long bones, is detected on a radiograph, several differential diagnoses can be made. Although fibrous dysplasia is usually not encountered as an epiphyseal lesion, it is important to incorporate all the clinical, radiographic and pathologic features to diagnose monostotic fibrous dysplasia when the lesion is located at the epiphyseal location.