Dong Hun Suh

Aseptic loosening of total hip arthroplasty: Infection always should be ruled out

BackgroundIt is believed that some cases of aseptic failure of THA may be attributable to occult infections. However, it is unclear whether preoperative erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are more likely elevated in these patients than those without overt infection.Questions/purposesWe asked whether some patients with aseptic THA failures have abnormal serologic indicators of periprosthetic joint infection (PJI) at the time of revision, namely ESR and/or CRP.MethodsThree hundred twenty-three revision THAs for aseptic loosening from 2004 to 2007 were retrospectively evaluated. We categorized all cases into two groups: (1) those with overt PJI (n = 14) plus patients who had a positive intraoperative culture during the index revision (n = 13) and (2) those who did not require rerevision (n = 276) or required surgery for noninfected causes (n = 20). Mean and frequency of abnormal ESR and CRP were compared between the two groups. The minimum followup was 11 months (average, 35 months; range, 11-54 months).ResultsThe mean and frequency of abnormal CRP in first group (n = 27) at 2.1 mg/dL and 48% respectively, were greater than those of the uninfected (n = 296) at 1.2 mg/dL and 27%, respectively. However, there were no differences between two groups regarding mean or frequency of abnormal ESR.ConclusionSome patients with presumed aseptic loosening may have abnormal serologic indicators of PJI that either have escaped diagnosis or were not adequately investigated. All patients undergoing revision THA should have ESR and CRP measured preoperatively and those with abnormal CRP should have additional evaluations to rule out or confirm PJI.Level of Evidence Level III, retrospective comparative study. See the Guidelines for Authors for a complete description of levels of evidence.

Fabrication of a BMP-2-immobilized porous microsphere modified by heparin for bone tissue engineering.

The purpose of this study was to fabricate BMP-2-immobilized porous poly(lactide-co-glycolide) (PLGA) microspheres (PMS) modified with heparin for bone regeneration. A fluidic device was used to fabricate PMS and the fabricated PMS was modified with heparin-dopamine (Hep-DOPA). Bone morphogenic protein-2 (BMP-2) was immobilized on the heparinized PMS (Hep-PMS) via electrostatic interactions. Both PMS and modified PMS were characterized using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). MG-63 cell activity on PMS and modified PMS were assessed via alkaline phosphatase (ALP) activity, calcium deposition, and osteocalcin and osteopontin mRNA expression. Immobilized Hep-DOPA and BMP-2 on PMS were demonstrated by XPS analysis. BMP-2-immobilized Hep-PMS provided significantly higher ALP activity, calcium deposition, and osteocalcin and osteopontin mRNA expression compared to PMS alone. These results suggest that BMP-2-immobilized Hep-PMS effectively improves MG-63 cell activity. In conclusion, BMP-2-immobilized Hep-PMS can be used to effectively regenerate bone defects.

Local delivery of alendronate eluting chitosan scaffold can effectively increase osteoblast functions and inhibit osteoclast differentiation

The aim of this study was to investigate the effect of alendronate released from chitosan scaffolds on enhancement of osteoblast functions and inhibition of osteoclast differentiation in vitro. The surface and cell morphologies of chitosan scaffolds and alendronate-loaded chitosan scaffolds were characterized by variable pressure field emission scanning electron microscope (VP-FE-SEM). Alendronate was released in a sustained manner. For evaluating osteoblast functions in MG-63 cells, we investigated cell proliferation, alkaline phosphatase (ALP) activity, and calcium deposition. Furthermore, for evaluating inhibition of osteoclast differentiation in RAW 264.7 cells, we investigated tartrate-resistant acid phosphatase (TRAP) activity, TRAP staining, and gene expressions. The in vitro studies revealed that osteoblasts grown on alendronate-loaded chitosan scaffold showed a significant increment in cell proliferation, ALP activity, and calcium deposition as compared to those grown on chitosan scaffolds. In addition, the in vitro study showed that osteoclast differentiation in RAW 264.7 cells cultured on alendronate-loaded chitosan scaffolds was greatly inhibited as compared to those cultured on chitosan scaffolds by the results of TRAP activity, TRAP staining, and gene expressions. Taken together, alendronate-loaded chitosan scaffolds could achieve the dual functions of improvement in osteoblast functions and inhibition of osteoclast differentiation. Thus, alendronate-eluting chitosan substrates are promising materials for enhancing osteoblast functions and inhibiting osteoclast differentiation in orthopedic and dental fields.

Effect of lactoferrin-impregnated porous poly(lactide-co-glycolide) (PLGA) microspheres on osteogenic differentiation of rabbit adipose-derived stem cells (rADSCs).

The aim of this study was to develop lactoferrin (LF)-impregnated porous poly(lactide-co-glycolide) (PLGA) microspheres (PMs) to induce osteogenic differentiation of rabbit adipose-derived stem cells (rADSCs). Porous PLGA PMs were fabricated by a fluidic device and their surfaces were modified with heparin-dopamine (Hep-DOPA). Then, LF (100μg, 500μg, and 1000μg) was impregnated on the surface of heparinized PMs (Hep-PMs) via electrostatic interactions to yield LF-impregnated PMs. PMs and modified PMs were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Osteogenic differentiation of rADSCs on PMs and modified PMs was demonstrated by alkaline phosphatase (ALP) activity, calcium deposition, and mRNA expression of osteocalcin and osteopontin. Successful immobilization of Hep-DOPA and LF on the surface of PMs was confirmed by XPS analysis. LF-impregnated PMs generated significantly greater ALP activity, calcium deposition, and mRNA expression of osteocalcin and osteopontin compared with PMs. These results suggested that LF-impregnated PMs effectively induced osteogenic differentiation of rADSCs.

Sonographic and electrophysiologic findings in patients with meralgia paresthetica

OBJECTIVE This study was aimed to demonstrate the usefulness of ultrasonography in the diagnosis of meralgia paresthetica (MP). METHODS Clinical data, sensory nerve conduction study and sonographic findings of 23 patients with unilateral MP were analyzed retrospectively. Twelve healthy subjects were recruited for the optimal cut-off value for the cross-sectional area of LFCN to diagnose MP using receiver operating characteristic curves. RESULTS The median value of the cross-sectional area of LFCN in healthy subjects was 3mm(2) and in the affected and unaffected sides in patients with MP, they were 11 and 6.5mm(2) around the anterior superior iliac spine level. The optimal cut-off value for the diagnosis of MP was 5mm(2). The location of LFCN on the affected side was superior to the inguinal ligament in 12 out of 23 cases (50%). CONCLUSION Ultrasonography is useful in the diagnosis of MP as a supplemental diagnostic tool, which gives important information about the morphologic changes that occur in the LFCN and its course. SIGNIFICANCE To the best of our knowledge, this is the first report to suggest that describe the cutoff value of the cross-sectional area of LFCN for the diagnosis of MP using ultrasonography.

Can pelvic tilting be ignored in total hip arthroplasty

INTRODUCTION The orientation of acetabular component is influenced by pelvic tilt, body position and individual variation in pelvic parameters. Most post-operative adverse events may be attributed to malposition of the component in the functional position. There is evidence that orientation of the pelvis changes from the supine to standing position. Authors report a case of recurrent dislocation after total hip arthroplasty due to excessive pelvic tilting. PRESENTATION OF CASE A 69-year old female with coxarthrosis had undergone total hip replacement with recurrent dislocation of the hip on bearing weight in spite of using constrained acetabular component. DISCUSSION Our case report substantiates the influence of pelvic tilt, incurred by a sagittal deformity of spine, on dynamic orientation of the acetabular cup which was positioned in accordance with the anatomic landmarks alone. If the reference is only bony architecture and dynamic positions of the pelvis are not taken into account, improper functional orientation of the acetabular cup can result in sitting and standing positions. These can induce instability even in anatomically appropriately oriented acetabular component. CONCLUSION The sagittal position of pelvis is a key factor in impingement and dislocation after total hip arthroplasty. Pelvic tilting affects the position of acetabular component in the sagittal plane of the body as compared with its anatomic position in the pelvis. We suggest a preoperative lateral view of spine-pelvis, in upright and supine position for evaluation of a corrective adaptation of the acetabular cup accordingly with pelvic balance.

Total ankle arthroplasty versus ankle arthrodesis for the treatment of end-stage ankle arthritis: a meta-analysis of comparative studies

PurposeTotal ankle arthroplasty (TAA) and ankle arthrodesis (AA) are the main surgical treatment options for end-stage ankle arthritis. Although the superiority of each modality remains debated, there remains a lack of high-quality evidence-based studies, such as randomized controlled clinical trials, and meta-analyses of comparative studies. We performed a meta-analysis of comparative studies to determine whether there is a significant difference between these two procedures in terms of (i) clinical scores and patient satisfaction, (ii) re-operations, and (iii) complications.MethodsWe conducted a comprehensive search in the MEDLINE, EMBASE, and Cochrane library databases. Only retrospective or prospective comparative studies were included in this meta-analysis. The literature search, data extraction, and quality assessment were conducted by two independent reviewers. The primary outcomes were clinical scores and patient satisfaction. We also investigated the prevalence of complications and the re-operation rate.ResultsTen comparative studies were included (four prospective and six retrospective studies). There were no significant differences between the two procedures in the American Orthopaedic Foot and Ankle Society ankle–hindfoot score, Short Form-36 physical component summary and mental component summary scores, visual analogue scale for pain, and patient satisfaction rate. The risk of re-operation and major surgical complications were significantly increased in the TAA group.ConclusionsThe meta-analysis revealed that TAA and AA could achieve similar clinical outcomes, whereas the incidence of re-operation and major surgical complication was significantly increased in TAA. Further studies of high methodological quality with long-term follow-up are required to confirm our conclusions.

Long-term results of arthroscopic excision of unstable osteochondral lesions of the lateral femoral condyle

The purpose of this study was to evaluate the long-term functional and radiological outcomes of arthroscopic removal of unstable osteochondral lesions with subchondral drilling in the lateral femoral condyle. We reviewed the outcome of 23 patients (28 knees) with stage III or IV osteochondritis dissecans lesions of the lateral femoral condyle at a mean follow-up of 14 years (10 to 19). The functional clinical outcomes were assessed using the Lysholm score, which improved from a mean of 38.1 (SD 3.5) pre-operatively to a mean of 87.3 (SD 5.4) at the most recent review (p = 0.034), and the Tegner activity score, which improved from a pre-operative median of 2 (0 to 3) to a median of 5 (3 to 7) at final follow-up (p = 0.021). The radiological degenerative changes were evaluated according to Tapper and Hoovers classification and when compared with the pre-operative findings, one knee had grade 1, 22 knees had grade 2 and five knees had grade 3 degenerative changes. The overall outcomes were assessed using Hughstons rating scale, where 19 knees were rated as good, four as fair and five as poor. We found radiological evidence of degenerative changes in the third or fourth decade of life at a mean of 14 years after arthroscopic excision of the loose body and subchondral drilling for an unstable osteochondral lesion of the lateral femoral condyle. Clinical and functional results were more satisfactory.

Clinical application of inside-out vein grafts for the treatment of sensory nerve segmental defect

The gold standard for the treatment of segmental nerve defect is an autogenous nerve graft. However, donor site morbidity is an inevitable complication. We substituted an autogenous nerve graft with an inside‐out vein graft for the treatment of segmental sensory nerve defect and the clinical results were evaluated retrospectively.

Radiographic appearance and patient outcome after ulnar shortening osteotomy for idiopathic ulnar impaction syndrome

PURPOSE Radiographic carpal chondromalacia (RCC) was defined as the presence of cortical sclerosis or subchondral changes, such as a lucent defect or cystic changes in a carpal on plain radiographs. The purpose of this study was to investigate the factors associated with the occurrence of RCC in idiopathic ulnar impaction syndrome and to determine the efficacy of ulnar shortening osteotomy on patient outcome and RCC. METHODS Thirty-nine patients (42 wrists) with idiopathic ulnar impaction syndrome were treated with either ulnar shortening osteotomy or arthroscopic wafer resection. Patients were divided into 2 groups according to the presence (RCC group; 17 patients, 19 wrists) or absence (non-RCC group: 22 patients, 23 wrists) of RCC on preoperative radiographs. To determine the factors associated with RCC, a comparative analysis of these 2 groups was performed with respect to sex, age, duration of symptoms, positive ulnar variance, pain scores, and Chun and Palmer grading system. The RCC area was measured on serial radiographs taken during follow-up. Progressive changes of RCC area and clinical outcomes were evaluated. RESULTS Patients in the RCC group were older, exhibited greater positive ulnar variance, and demonstrated a significantly higher mean pain score before surgery. The RCC was found to reverse over the year following ulnar shortening osteotomy and did not recur up to 2 years after surgery. In 3 wrists, RCC had completely disappeared at the last follow-up. All patients showed improved clinical outcomes. CONCLUSIONS The RCC changes correlated with older age, a positive ulnar variance, and preoperative pain severity. The RCC progressively reversed after ulnar shortening osteotomy, and this reversal of radiographic changes correlated with clinical improvements. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.