Ta-Wei Tai

Tourniquet use in total knee arthroplasty: a meta-analysis

PurposeThe use of an intraoperative tourniquet for total knee arthroplasty (TKA) is a common practice. However, the effectiveness and safety are still questionable. A systematic review was conducted to examine that whether using a tourniquet in TKA was effective without increasing the risk of complications.MethodsA comprehensive literature search was done in PubMed Medicine, Embase, and other internet database. The review work and the following meta-analysis were processed to evaluate the role of tourniquet in TKA.ResultsEight randomized controlled trials and three high-quality prospective studies involving 634 knees and comparing TKA with and without the use of a tourniquet were included in this analysis. The results demonstrated that using a tourniquet could decrease the measured blood loss but could not decrease the calculated blood loss, which indicated actual blood loss. Patients managed with a tourniquet might have higher risks of thromboembolic complications. Using the tourniquet with late release after wound closure could shorten the operation time; whereas early release did not show this benefit.ConclusionsThe current evidence suggested that using tourniquet in TKA may save time but may not reduce the blood loss. Due to the higher risks of thromboembolic complications, we should use a tourniquet in TKA with caution.

Temporary drainage clamping after total knee arthroplasty: a meta-analysis of randomized controlled trials.

Drainage-clamping methods are thought to be effective in reducing blood loss after total knee arthroplasty (TKA). We conducted a systematic review to examine if these methods were effective without increasing the risk of complications. After a comprehensive search, 6 randomized controlled trials involving 603 knees and comparing clamping drainage and the immediate release of the drain after elective TKA were included in this analysis. The results demonstrated that drainage clamping could decrease the volume of drainage, but only clamping for no less than 4 hours could reduce the true blood loss. There was no significant difference between the 2 groups regarding blood transfusion, postoperative range of motion, incidence of thromboembolic events, and wound complications. The current evidence cannot confirm the advantage of clamping drainage after TKA.

Clinical and Ultrasonographic Results of Ultrasonographically Guided Percutaneous Radiofrequency Lesioning in the Treatment of Recalcitrant Lateral Epicondylitis

Background: In patients with lateral epicondylitis recalcitrant to nonsurgical treatments, surgical intervention is considered. Despite the numerous therapies reported, the current trend of treatment places particular emphasis on minimally invasive techniques. Purpose: The authors present a newly developed minimally invasive procedure, ultrasonographically guided percutaneous radiofrequency thermal lesioning (RTL), and its clinical efficacy in treating recalcitrant lateral epicondylitis. Study Design: Case series: Level of evidence, 4. Methods: Thirty-four patients (35 elbows), with a mean age of 52.1 years (range, 35-65 years), suffered from symptomatic lateral epicondylitis for more than 6 months and had exhausted nonoperative therapies. They were treated with ultrasonographically guided RTL. Patients were followed up at least 6 months by physical examination and 12 months by interview. The intensity of pain was recorded with a visual analog scale (VAS) score. The functional outcome was evaluated using grip strength, the upper limb Disability of Arm, Shoulder and Hand (QuickDASH) outcome measure, and the Modified Mayo Clinic Performance Index (MMCPI) for the elbow. The ultrasonographic findings regarding the extensor tendon origin were recorded, as were the complications. Results: At the time of the 6-month follow-up, the average VAS score in resting (from 4.9 to 0.9), palpation (from 7.6 to 2.5), and grip (from 8.2 to 2.9) had improved significantly compared with the preoperative condition (P < .01). The grip strength (from 20.6 to 27.0 kg) and QuickDASH score (from 54.3 to 21.0) had also improved significantly (P < .01). The MMCPI score improved from “poor” to “excellent.” The ultrasonographic finding revealed that the thickness of the common extensor tendon origin did not change significantly. At the final follow-up (mean, 14.3 months; range, 12-21 months), the patients reported a 78% reduction in pain compared with the preoperative status. No major complications were noted in any patient. Conclusion: Ultrasonographically guided RTL for recalcitrant lateral epicondylitis was found to be a minimally invasive treatment with satisfactory results in this pilot investigation. This innovative method can be considered as an alternative treatment of recalcitrant lateral epicondylitis before further surgical intervention.

Activation of p38 MAPK-regulated Bcl-xL signaling increases survival against zoledronic acid-induced apoptosis in osteoclast precursors.

The nitrogen-containing bisphosphonate zoledronic acid (ZA) induces apoptosis in osteoclasts and inhibits osteoclast-mediated bone resorption. It is widely used to treat osteoporosis. However, some patients are less responsive to ZA treatment, and the mechanisms of resistance are still unclear. Here, we identified that murine osteoclast precursors may develop resistance to ZA-induced apoptosis. These resistant cells survived the apoptotic effect of ZA following an increase in anti-apoptotic Bcl-xL. Pharmacologically inhibiting Bcl-xL facilitated ZA-induced apoptosis. Treatment with ZA activated p38 MAPK, increasing Bcl-xL expression and cell survival. Nuclear import of β-catenin regulated by p38 MAPK determined Bcl-xL mRNA expression and cell survival in response to ZA. ZA also inactivated glycogen synthase kinase (GSK)-3β, a negative upstream regulator of β-catenin, in a p38 MAPK-mediated manner. Synergistic pharmacological inhibition of p38 MAPK with ZA attenuated receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclast differentiation and facilitated ZA-induced apoptosis. These results demonstrate that elevated Bcl-xL expression mediated by p38 MAPK-regulated GSK-3β/β-catenin signaling is required for cell survival of ZA-induced apoptosis in both osteoclast precursors and osteoclasts. Finally, we demonstrated that inhibiting p38 MAPK-mediated pathway enhanced ZA effect on increasing the bone mineral density of ovariectomized mice. This result suggests that targeting these pathways may represent a potential therapeutic strategy.

The effects of forearm fatigue on baseball fastball pitching, with implications about elbow injury

ABSTRACT This study investigated the contribution of flexor muscles to the forearm through fatigue; therefore, the differences in forearm mechanisms on the pitching motion in fastball were analysed. Fifteen baseball pitchers were included in this study. Ultrasonographical examination of participants’ ulnar nerve in the cubital tunnel with the elbow extended and at 45°, 90° and 120° of flexion was carried. A three-dimensional motion analysis system with 14 reflective markers attached on participants was used for motion data collection. The electromyography system was applied over the flexor carpi ulnaris, flexor carpi radialis and extensor carpi radialis muscles of the dominant arm. Flexor carpi ulnaris muscle activity showed a significant difference during the acceleration phase, with a peak value during fastball post-fatigue (P = 0.02). Significant differences in the distance between ulnar nerve and medial condyle on throwing arm and non-throwing arm were observed as the distance increased with the elbow movement from 0° to 120° of flexion (P = 0.01). The significant increase of the flexor carpi ulnaris muscle activity might be responsible for maintaining the stability of the wrist joint. The increased diameter might compress the ulnar nerve and cause several pathological changes. Therefore, fatigue in baseball pitchers still poses a threat to the ulnar nerve because the flexor carpi ulnaris and flexor carpi radialis all originate from the medial side of the elbow, and the swelling tendons after fatigue might be a key point.

The Role of Drainage After Total Knee Arthroplasty

Total knee arthroplasty (TKA) is associated with significant postoperative blood loss for which blood transfusion might be necessary. The role of wound drainage is controversial. The use of drainage was believed to be effective in decreasing hematoma formation (Drinkwater and Neil 1995; Holt et al. 1997; Martin et al. 2004), which has been theoretically thought to decrease postoperative pain, swelling, and incidence of infection(Kim et al. 1998). However, a closed suction drainage system inevitably increases bleeding because the tamponade effect of a closed and undrained wound is eliminated. Though some studies have shown that drainage after TKA is not necessary(Adalberth et al. 1998; Niskanen et al. 2000; Esler et al. 2003; Parker et al. 2004; Jones et al. 2007), it is still widely used by orthopedic surgeons(Canty et al. 2003). Surgeons who routinely drain total knee replacements may also use adjunctive measures such as autologous blood transfusion, use of fibrin tissue adhesive, compression bandaging and local ice packing(Gibbons et al. 2001; Kullenberg et al. 2006; Radkowski et al. 2007) to reduce the excessive blood loss from the drain. Recently, drain clamping has received increasing attention. Since most of the blood loss in TKA occurs during the first few postoperative hours (37% in 2 hours and 55% in 4 hours)(Jou IM 1993; Senthil Kumar et al. 2005), it seems reasonable to clamp the drain tube in the first few hours after TKA to temporarily create a tamponade effect for bleeding control. Various methods of clamping drain have been reported in the literature. However, no consensus has been achieved to date. To clarify the role of drainage system after total knee arthroplasty, we conduct a review process in the present project. A comprehensive search was carried out and the articles regarding the drainage after surgery were reviewed. This review article focused on: 1. Effectiveness of postoperative drainage in TKA. 2. Safety and complications of postoperative drainage in TKA. 3. Effect of temporary drain clamping. The purpose of this article is to analyze the pros and cons in using the drainage system after total knee arthroplasty and to provide practical information for orthopedic surgeons and medical care givers.

Efficacy of topical cross‐linked hyaluronic acid hydrogel in preventing post laminectomy/laminotomy fibrosis in a rat model

Post‐laminectomy/laminotomy epidural fibrosis (EF) has been implicated as an important cause of failed back syndrome (FBS). The various clinical approaches used to control EF yield mixed outcomes. Cross‐linked hyaluronic acid hydrogel (cHA) was synthesized to increase mechanical stability and residence time. We evaluated the therapeutic attenuation of proliferative EF in laminectomy/laminotomy groups treated and not treated with cHA. A bilateral T11‐L1 total laminectomy or unilateral T12 laminotomy was done on four groups (n = 10 each) of Sprague‐Dawley rats and then histologically examined 2 months post‐surgery: (I) laminectomy group treated with and (II) not treated with cHA, (III) laminotomy group treated with and (IV) not treated with cHA. The grade of EF, the diameters within the spinal canal, dura mater thickness, and the area of the epidural space, subarachnoid space, and conus medullaris space were assessed. The cHA‐treated subgroups (I, III) had a significantly lower grade of EF, thinner dura mater, and larger epidural and subarachnoid spaces than did the control subgroups (II, IV) (p < 0.05). The cHA formed a solid interpositional membrane barrier that prevented invasive fibrosis, and also helped reduce pathological changes to the adjacent structures. In conclusion, topically applied cHA is effective for reducing EF.

Changes in excursion and strain in the rat sciatic nerve under cauda equina compression induced by epidural balloon inflation.

BACKGROUND CONTEXT Healthy nerves are able to stretch and glide as responses to normal physiological movement. Injury to the nerve may alter the nerves mechanical properties and result in neuropathy. Whether cauda equina compression alters the mechanical properties of the sciatic nerve is still unclear. PURPOSE The purpose of this study was to demonstrate the changes in excursions and strains of the sciatic nerve in vivo after acute cauda equina compression was induced by epidural balloon compression. STUDY DESIGN An animal comparative study with induced cauda equina compression was designed for in situ measurements of nerve properties. METHODS Twenty-six adult Sprague-Dawley rats were divided into three groups. The balloon group (n=10) underwent epidural compression induced by inflation of an embolectomy balloon catheter that was inserted through an L6 laminotomy. The control group (n=10) underwent laminotomy but without compression. The normal group (n=6) received no back surgery. This model of neuropathy was confirmed with electrophysiological examination. The excursions and strains of the sciatic nerve in response to the modified straight leg-raising (SLR) test were measured in situ and analyzed. RESULTS The scales of the excursions were lower in the balloon group than in the other two groups, in both 90° flexion and extension of the knee. The balloon group was more sensitive to positional changes. The strain was significantly higher under the condition of epidural balloon compression. CONCLUSIONS We concluded that cauda equina compression decreased the excursion and increased the strain of the sciatic nerve in response to a modified SLR test. These findings might indicate one of the mechanisms of the pain provoked by the SLR test and also possibly contribute to an understanding of the pathogenesis of the neuropathy in the lower limbs of patients with cauda equina compression.

Using a cannulated screw as a drill guide and sleeve: A simple technique for multiple-screw fixation for intracapsular femoral neck fracture

Management of femoral neck fractures is a challenge to orthopedic surgeons. Anatomical reduction and stable fixation is mandatory for nondisplaced or impacted intracapsular femoral neck fractures. This article introduces a simple method of parallel screw fixation for intracapsular femoral neck fracture based on the AO technique.We used a cannulated screw as a drill guide and sleeve rather than a commercial kit. With the 2-plane radiographic images, the surgeon could fine-tune the cannulated screw to direct the guide pin insertion and avoid deflection. Then the screw could be inserted for permanent fixation. This method accelerated the procedure and minimized the incisions and soft tissue dissection. The short-term results of 11 patients were compared with those of patients managed with the conventional screw fixation technique and the patients fixed with the dynamic hip system with an anti-rotation screw.This minimally invasive technique is time saving, easy to apply, and useful when commercial kits are unavailable. It facilitates and simplifies the minimally invasive parallel screw fixation procedure for intracapsular femoral neck fractures.

Sesame oil improves functional recovery by attenuating nerve oxidative stress in a mouse model of acute peripheral nerve injury: role of Nrf-2.

Peripheral nervous injury (PNI) is a common form of trauma in modern society, especially in sport players. Despite the advance of therapy for PNI, the recovery of function can never reach the preinjury level after treatments. Recently, inhibiting neural oxidative stress shows a beneficial effect in improving functional recovery after PNI. In addition, sesame oil has been reported to possess the excellent antioxidative properties. However, whether sesame oil can improve the functional recovery after PNI by its antioxidative effect has never been investigated. Thirty mice were randomly divided into five groups of six: group I mice received sham operation; group II mice received sciatic nerve crush; and groups III-V mice daily ingested 0.5, 1 and 2 ml/kg of sesame oil for 6 days, respectively, after sciatic nerve crush. Oxidative stress, GAP43 and nuclear Nrf2 levels as well as spinal somatosensory evoked potentials were assessed on day 6, while paw withdrawal latency and sciatic function index were assessed on days 0, 3, and 6. Sesame oil significantly decreased lipid peroxidation and increased nuclear factor erythroid 2-related factor 2 and GAP43 expression in sciatic nerve. Furthermore, sesame oil improved electrophysiological and functional assessments in mice with sciatic nerve crush. In conclusion, sesame oil may improve nerve functional recovery by attenuating nerve oxidative stress in mouse acute peripheral nerve injury. Further, application of natural product sesame oil may be an alternative approach for improving nerve functional recovery in the clinical setting.