Kuen Tak Suh

Direct comparison of human mesenchymal stem cells derived from adipose tissues and bone marrow in mediating neovascularization in response to vascular ischemia.

Background/Aim: Although transplantation of MSC derived from bone marrow or adipose tissues has been shown in proangiogenic action in hindlimb ischemia model of nude mice, little information is available regarding comparison of the angiogenic potency between human adipose stromal cells (hADSC) and bone marrow stromal cells (hBMSC). We compared their therapeutic potential by transplantation of equal numbers of hADSC or hBMSC in a nude mice model of hindlimb ischemia. Methods&Results: One day after creating hindlimb ischemia, mice were randomized to receive hADSC transplantation (hADSC group), hBMSC transplantation (hBMSC group), or vehicle transplantation (Control group). Two weeks after transplantation, the laser Doppler perfusion index was significantly higher in the hADSC group and hBMSC group than in the control group. Comparison between hADSC and hBMSC group showed better recovery of blood flow in hADSC group than in hBMSC group. Conditioned media from hADSC (hADSC-CM) showed better in vitro tube formation of hADSC than conditioned media from hBMSC (hBMSC-CM). hADSC showed higher expression of MMP3 and MMP9 than hBMSC. A MMP inhibitor, GM6001, and the transfection of MMP3 or MMP9 siRNA oligonucleotides inhibited in vitro tube formation of hADSC. Transplantation of MMP3 or MMP9 siRNA oligonucleotieds-transfected hADSC showed lower blood flow recovery and higher tissue injury than control oligonucelotide-transfected cells. Conclusion: This study showed that hADSC can be an ideal source for therapeutic angiogenesis in ischemic disease in terms of efficacy, accessibility and available tissue amounts.

A posterior approach to primary total hip arthroplasty with soft tissue repair.

To determine whether repair of the posterior soft tissue structures affects dislocation rate, a comparison of the posterolateral approach with and without a posterior soft tissue repair in primary total hip arthroplasty was done. Between January 1993 and December 1998, 250 consecutive primary total hip arthroplasties (220 patients) without a posterior soft tissue repair followed by 96 consecutive primary total hip arthroplasties (83 patients) with a posterior soft tissue repair in the posterolateral approach were done. With the exception of a posterior soft tissue repair, all surgical procedures were done in the same manner. A dislocation rate of 6.4% in 250 hips without a posterior soft tissue repair in the posterolateral approach was reduced to 1% in 96 hips with a posterior soft tissue repair. The results were statistically significant. The current results indicate that the posterior structures should be preserved as much as possible and repaired to reduce dislocation in the posterolateral approach.

Decreased osteogenic differentiation of mesenchymal stem cells in alcohol-induced osteonecrosis.

We postulated that osteogenic and adipogenic differentiation ability of the mesenchymal stem cells isolated from the bone marrow could be altered in patients with alcohol-induced osteonecrosis of the femoral head. To examine this hypothesis, we investigated the differentiation ability of the mesenchymal stem cells isolated from the bone marrow from the proximal end of the femur during hip replacements in patients with alcohol-induced osteonecrosis of the femoral head and compared it with the differentiation ability of patients with femoral neck fractures. Marrow was collected from the proximal femurs of 33 patients having hip replacement for either alcohol-induced osteonecrosis of the femoral head or femoral neck fractures. The mesenchymal stem cells were isolated and the culture was expanded from the marrow. The cell populations were compared in terms of the doubling time and the differentiation ability to the osteoblasts and adipocytes. The cells obtained from the patients with alcohol-induced osteonecrosis of the femoral head showed a reduced ability to differentiate the osteogenic lineages compared with the cells obtained from the patients with femoral neck fractures. Such changes may play a role in the development of alcohol-induced osteonecrosis of the femoral head. The altered function of mesenchymal stem cells can be responsible for the pathogenesis of osteonecrosis.

Comparison of preoperative templating with postoperative assessment in cementless total hip arthroplasty.

We studied how preoperative templating corresponded to the postoperative leg length in total hip arthroplasty.On average, the preoperative predictive value of the desired corrective change in leg length was +4.9 (+4.0–+6.7) mm, while the true postoperative assessed value of the corrective change in leg length was +4.7 (+4.0–+6.3) mm. On preoperative radiographs, the ratio of the horizontal offset of a pathological side to a normal side was 95%, on average, and it increased to 96%, on average, after an operation. Preoperatively planned sizes of the acetabular cup and the femoral stem by templating showed a high rate of coincidence with the sizes used intraoperatively.In conclusion, an accurate and careful preoperative templating can result in a balanced hip reconstruction by correcting the leg length differences and restoring the offsets.

Pineal gland metabolism in patients with adolescent idiopathic scoliosis

The scoliosis observed in chickens after pinealectomy resembles that seen in humans with an adolescent idiopathic scoliosis, suggesting that melatonin deficiency may be responsible. However, to date there have been no studies of pineal gland glucose metabolism in patients with adolescent idiopathic scoliosis that might support this hypothesis. We examined the excretion of urinary 6-sulfatoxyl-melatonin as well as the glucose metabolism of the pineal gland in 14 patients with an adolescent idiopathic scoliosis and compared them with those of 13 gender-matched healthy controls using F-18 fluorodeoxyglucose brain positron emission tomography. There was no significant difference in the level of urinary 6-sulfatoxyl-melatonin or pineal gland metabolism between the study and the control group. We conclude that permanent melatonin deficiency is not a causative factor in the aetiology of adolescent idiopathic scoliosis.

Posterior lumbar interbody fusion and posterior instrumentation in the surgical management of lumbar tuberculous spondylitis

There are few reports of the treatment of lumbar tuberculous spondylitis using the posterior approach. Between January 1999 and February 2004, 16 patients underwent posterior lumbar interbody fusion with autogenous iliac-bone grafting and pedicle screw instrumentation. Their mean age at surgery was 51 years (28 to 66). The mean follow-up period was 33 months (24 to 48). The clinical outcome was assessed using the Frankel neurological classification and the Kirkaldy-Willis criteria. On the Frankel classification, one patient improved by two grades (C to E), seven by one grade, and eight showed no change. The Kirkaldy-Willis functional outcome was classified as excellent in eight patients, good in five, fair in two and poor in one. Bony union was achieved within one year in 15 patients. The mean pre-operative lordotic angle was 27.8 degrees (9 degrees to 45 degrees ) which improved by the final follow-up to 35.8 degrees (28 degrees to 48 degrees ). Post-operative complications occurred in four patients, transient root injury in two, a superficial wound infection in one and a deep wound infection in one, in whom the implant was removed. Our results show that a posterior lumbar interbody fusion with autogenous iliac-bone grafting and pedicle screw instrumentation for tuberculous spondylitis through the posterior approach can give satisfactory results.

Prediction of residual disease of spine infection using F-18 FDG PET/CT.

Study Design. Prospective study. Objective. To determine whether F-18 fluoro-deoxy-glucose positron emission tomography/computed tomography (F-18 FDG PET/CT) follow-up imaging after treatment in patients with spinal infection (SI) could provide useful prognostic information and determine the residual SI. Summary of Background Data. There are seldom data on the capability of follow-up imaging methods to predict residual disease and treatment efficacy in patients with SI. Methods. Thirty patients with SI underwent F-18 FDG PET/CT at initial and during follow-up. From F-18 FDG PET/CT, quantitative indexes were obtained. The residual SI was determined by the presence of preoperative symptoms, hematological infection marker, and radiologic findings. Results. The SUVmax were significantly declined after treatment in both of residual (2.85 ± 1.17 vs. 2.06 ± 1.03; P < 0.0001) and nonresidual SI (4.31 ± 2.07 vs. 1.44 ± 0.46; P < 0.0001). The SUVmean were also decreased after treatment in both of residual (1.45 ± 0.45 vs. 1.04 ± 0.29; P = 0.0014) and nonresidual SI (2.09 ± 1.03 vs. 0.81 ± 0.25; P < 0.0001). By lesion-based analysis, when ≤43.01% of %&dgr;SUVmax was used as threshold value, the area under curve (AUC) was 0.879 (P = 0.0001). The sensitivity and specificity were 85.7% and 82.6%, respectively. When ≤44.12% of %&dgr;SUVmean was used as threshold value, AUC was 0.828 (P = 0.0001). The sensitivity and specificity were 85.7% and 68%, respectively. In patient-based analysis, when ≤46.14% of %&dgr;SUVmax was used as threshold value, AUC was 0.904 (P = 0.0001). The sensitivity and specificity were 100% and 76.9%, respectively. When ≤41.78% of %&dgr;SUVmean was used as threshold value, AUC was 0.923 (P = 0.0001). The sensitivity and specificity were 100%, 76.9%, respectively. Conclusion. F-18 FDG PET/CT is useful for discrimination of residual and nonresidual SI after treatment. Among the various quantitative indexes, %&dgr;SUVmax is a potent predictor of residual SI in the current study.

Arthroscopic Repair of Combined Bankart and SLAP Lesions: Operative Techniques and Clinical Results

Background To evaluate the clinical results and operation technique of arthroscopic repair of combined Bankart and superior labrum anterior to posterior (SLAP) lesions, all of which had an anterior-inferior Bankart lesion that continued superiorly to include separation of the biceps anchor in the patients presenting recurrent shoulder dislocations. Methods From May 2003 to January 2006, we reviewed 15 cases with combined Bankart and SLAP lesions among 62 patients with recurrent shoulder dislocations who underwent arthroscopic repair. The average age at surgery was 24.2 years (range, 16 to 38 years), with an average follow-up period of 15 months (range, 13 to 28 months). During the operation, we repaired the unstable SLAP lesion first with absorbable suture anchors and then also repaired Bankart lesion from the inferior to superior fashion. We analyzed the preoperative and postoperative results by visual analogue scale (VAS) for pain, the range of motion, American Shoulder and Elbow Surgeon (ASES) and Rowe shoulder scoring systems. We compared the results with the isolated Bankart lesion. Results VAS for pain was decreased from preoperative 4.9 to postoperative 1.9. Mean ASES and Rowe shoulder scores were improved from preoperative 56.4 and 33.7 to postoperative 91.8 and 94.1, respectively. There were no specific complication and no significant limitation of motion more than 10 degree at final follow-up. We found the range of motions after the arthroscopic repair in combined lesions were gained more slowly than in patients with isolated Bankart lesions. Conclusions In recurrent dislocation of the shoulder with combined Bankart and SLAP lesion, arthroscopic repair using absorbable suture anchors produced favorable clinical results. Although it has technical difficulty, the concomitant unstable SLAP lesion should be repaired in a manner that stabilizes the glenohumeral joint, as the Bankart lesion can be repaired if the unstable SLAP lesion is repaired first.

Avascular necrosis after fracture-separation of the distal end of the humerus in children.

Fracture-separation of the distal end of the humerus in children has been reported infrequently, and may be misdiagnosed as a fracture of the condyle or a traumatic dislocation of the elbow. We discuss eight cases of a seldom reported complication following fracture-separation of the distal end of the humerus. This complication consists of dissolution of the trochlea within three to six weeks postinjury and a defect of the medial or central part of the condyle that develops later. The fractures were severely displaced fracture-separation of the distal end of the humerus with large medial or lateral metaphyseal fragment, but initially misdiagnosed as a fracture of the medial, lateral condyle or a traumatic dislocation of the elbow in six of eight cases. We performed open reduction in six cases because of initial misdiagnosis or because of difficulty in satisfactory closed reduction. We speculated that this complication is due to avascular necrosis of the distal end of the humerus, and that fracture-separation of the distal end of the humerus is more common than reported.

Does Zoledronate Prevent Femoral Head Collapse from Osteonecrosis? A Prospective, Randomized, Open-Label, Multicenter Study.

BACKGROUND Osteonecrosis of the femoral head frequently leads to collapse of the necrotic portion and subsequent degenerative joint disease of the hip, which is the most common diagnosis leading to total hip arthroplasty in young adults. Bisphosphonate therapy has been reported to potentially retard the collapse. We conducted a two-year prospective, randomized, open-label, multicenter study to determine whether zoledronate prevents the collapse and reduces the need for total hip arthroplasty. METHODS We randomly assigned patients who had Steinberg stage-I or II nontraumatic osteonecrosis of the femoral head with a necrotic area of ≥30% to either the zoledronate group or the control group. Patients in the zoledronate group received 5 mg of zoledronate intravenously per year for two years, while patients in the control group did not receive this medication. The primary efficacy outcome was the survival rate in terms of the occurrence of collapse (≥2 mm). The patients were observed for a minimum of two years after enrollment. RESULTS A total of 110 patients (110 hips) underwent randomization; fifty-five patients were assigned to the zoledronate group and fifty-five, to the control group. During the two-year follow-up, twenty-nine femoral heads in the zoledronate group and twenty-two in the control group collapsed (p > 0.05). Nineteen hips in the zoledronate group and twenty in the control group underwent total hip arthroplasty (p > 0.05). CONCLUSIONS Zoledronate for Steinberg stage-I or II osteonecrosis of the femoral head, with a medium to large necrotic area, did not prevent the collapse of the femoral head or reduce the need for total hip arthroplasty. LEVEL OF EVIDENCE Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.