Gianfranco Fraschini

Interscalene Brachial Plexus Anesthesia and Analgesia for Open Shoulder Surgery: A Randomized, Double-Blinded Comparison Between Levobupivacaine and Ropivacaine

UNLABELLED We compared the onset time and quality of interscalene brachial plexus block produced with levobupivacaine and ropivacaine in 50 patients undergoing open shoulder surgery randomly allocated to receive 30 mL of 0.5% levobupivacaine (n = 25) or 0.5% ropivacaine (n = 25) injected through a 20-gauge catheter placed into the interscalene sheath using a 18-gauge insulated and stimulating Tuohy introducer. The block was also prolonged after surgery using a patient-controlled interscalene analgesia with 0.125% levobupivacaine or 0.2% ropivacaine, respectively (basal infusion rate, 6 mL/h; bolus, 2 mL; lockout period, 15 min; maximum boluses per hour, three). Three patients (two with levobupivacaine [8%] and one with ropivacaine [4%]) failed to achieve surgical block within 45 min after the injection and were excluded. The onset time of surgical block was 20 min (10-40 min) with levobupivacaine and 20 min (5-45 min) with ropivacaine (P = 0.53). Rescue intraoperative analgesia (0.1 mg of fentanyl IV) was required in eight patients in each group (34%) (P = 0.99). Forty-two patients completed the 24-h postoperative infusion (22 with levobupivacaine and 20 with ropivacaine). Postoperative analgesia was similarly effective in both groups. Total consumption of local anesthetic infused during the first 24 h was 147 mL (144-196 mL) with levobupivacaine and 162 mL (144-248 mL) with ropivacaine (P = 0.019), with a ratio between boluses received and requested of 0.8 (0.4-1.0) and 0.7 (0.4-1.0), respectively (P = 0.004). The degree of motor block of the operated limb was deeper with levobupivacaine than ropivacaine when starting postoperative analgesia; however, no further differences in degree of motor function were observed between the two groups. We conclude that 30 mL of levobupivacaine 0.5% induces an interscalene brachial plexus anesthesia of similar onset and intensity as the one produced by the same volume and concentration of ropivacaine. Postoperative interscalene analgesia with 0.125% levobupivacaine results in similar pain relief and recovery of motor function with less volume of local anesthetic than with 0.2% ropivacaine. IMPLICATIONS This prospective, randomized, double-blinded study demonstrates that 30 mL of 0.5% levobupivacaine produces an interscalene brachial plexus block of similar onset and quality as the one produced by the same volume of 0.5% ropivacaine. When prolonging the block after surgery, 0.125% levobupivacaine provides adequate pain relief and recovery of motor function after open shoulder surgery, with less volume infused during the first 24 h after surgery than 0.2% ropivacaine.

The Benefit of Synthetic Versus Biological Patch Augmentation in the Repair of Posterosuperior Massive Rotator Cuff Tears A 3-Year Follow-up Study

Background: Rotator cuff repair typically results in a satisfactory, although variable, clinical outcome. However, anatomic failure of the repaired tendon often occurs. Hypothesis: Patch augmentation can improve the results of open rotator cuff repair by supporting the healing process, protecting the suture, and reducing friction in the subacromial space. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 152 patients with a posterosuperior massive rotator cuff tear were treated by open repair only (control group; n = 51; mean age, 67.06 ± 4.42 years), open repair together with collagen patch augmentation (collagen group; n = 49; mean age, 66.53 ± 5.17 years), or open repair together with polypropylene patch augmentation (polypropylene group; n = 52; mean age, 66.17 ± 5.44 years) and were retrospectively studied. Patients were evaluated preoperatively and after 36 months with a visual analog scale (VAS) and the University of California, Los Angeles (UCLA) shoulder rating scale and by measuring elevation of the scapular plane and strength with a dynamometer. The VAS and UCLA scores were also obtained 2 months postoperatively. Tendon integrity was assessed after 1 year by ultrasound. Patients were homogeneous as per the preoperative assessment. Results: After 2 months, results (mean ± standard deviation) for the control, collagen, and polypropylene groups, respectively, were as follows: VAS scores were 6.96 ± 1.11, 6.46 ± 1.02, and 4.92 ± 0.90, while UCLA scores were 11.29 ± 1.46, 11.40 ± 1.51, and 19.15 ± 1.99. After 36 months, the mean scores for the respective groups were 3.66 ± 1.05, 4.06 ± 1.02, and 3.28 ± 1.10 for the VAS and 14.88 ± 1.98, 14.69 ± 1.99, and 24.61 ± 3.22 for the UCLA scale. In addition, after 36 months, elevation on the scapular plane was 140.68° ± 9.84°, 140.61° ± 12.48°, and 174.71° ± 8.18°, and abduction strength was 8.73 ± 0.54 kg, 9.03 ± 0.60 kg, and 13.79 ± 0.64 kg for the control, collagen, and polypropylene groups, respectively. The retear rate after 12 months was 41% (21/51) for the control group, 51% (25/49) for the collagen group, and 17% (9/52) for the polypropylene group. In particular, the reduced 12-month retear rate and the increased UCLA scores, abduction strength, and elevation at 3-year follow-up were statistically significant for patients treated with a polypropylene patch compared with those treated with repair only or with a collagen patch. Conclusion: Polypropylene patch augmentation of rotator cuff repair was demonstrated to significantly improve the 36-month outcome in terms of function, strength, and retear rate.

Surgical treatment of chronic acromioclavicular dislocation: Comparison between two surgical procedures for anatomic reconstruction

INTRODUCTION Surgical treatment of chronic complete acromioclavicular (AC) joint dislocation is still debated and no gold standard surgical procedure has been identified. MATERIALS AND METHODS A retrospective series of 90 patients treated for AC dislocations is reported here. Patients were divided into three groups: group 1 receiving AC reconstruction with a Dacron vascular prosthesis; group 2 receiving AC reconstruction with LARS(®) artificial ligament; group 3 receiving conservative treatment. Follow-up was performed after 1, 6 and 15 months with plain radiographs, UCLA, SPADI and modified UCLA acromioclavicular rating scales. RESULTS Patients treated surgically presented significant better functional outcome compared to patients treated conservatively with overall positive results in 93.3% of patients for group 2 and 53.3% of patients for group 1. However, reconstruction with Dacron vascular prosthesis presented an unacceptable high complications rate (43.3%). CONCLUSION Our results show that anatomic AC reconstruction with LARS(®) artificial ligament resulted in both satisfactory functional outcome and low complication rate. Therefore, we recommend this procedure for the treatment of chronic complete AC dislocations.

Calcitonin gene-related peptide (CGRP) inhibits apoptosis in human osteoblasts by β-catenin stabilization.

Transgenic mice over‐expressing calcitonin gene‐related peptide (CGRP) in osteoblasts have increased bone density due to increased bone formation, thus suggesting that CGRP plays a role in bone metabolism. In this study we determined the relationship between CGRP, the canonical Wnt signaling and apoptosis in human osteoblasts (hOBs) in consideration of the well‐documented involvement of this pathway in bone cells. Primary cultures of hOBs were treated with CGRP 10−8 M. Levels of β‐catenin, which is the cytoplasmic protein mediator of canonical Wnt signaling, and mRNA were determined. CGRP increases both the expression and the levels of cytoplasmic β‐catenin by binding to its receptor, as this effect is blocked by the antagonist CGRP8–37. This facilitatory action on β‐catenin appears to be mediated by the inhibition of the enzyme GSK‐3β via protein kinase A (PKA) activation. GSK‐3β is a glycogen synthase kinase that, by phosphorylating β‐catenin, promotes its degradation by the proteosomal machinery. Moreover, the peptide is able to inhibit hOBs apoptosis stimulated by dexamethasone or by serum deprivation, possibly through the accumulation of β‐catenin, since the inhibitor of PKA activity H89 partially prevents the antiapoptotic effect of the peptide. In conclusion CGRP, released by nerve fibers, exerts its anabolic action on bone cells by stimulating canonical Wnt signaling and by inhibiting hOBs apoptosis, thus favoring local bone regeneration. J. Cell. Physiol. 225: 701–708, 2010.

A tissue engineered osteochondral plug : an in vitro morphological evaluation

Articular cartilage lesions have a poor intrinsic healing potential. The repair tissue is often fibrous, having insufficient biomechanical properties, which could frequently lead to the development of early osteoarthritis. In the last decade, tissue engineering approaches addressed this topic in order to restore joint function with a differentiated and functional tissue. Many biomaterials and techniques have been proposed and some of them applied in clinical practice, even though several concerns have been raised on the quality of the engineered tissue and on its integration in the host joint. In this study, we focused on engineering in vitro a biphasic composite made of cellular fibrin glue and a calcium–phosphate scaffold. Biphasic composites are the latest products of tissue engineering applied to articular cartilage and they seem to allow a more efficient integration of the engineered tissue with the host. However, a firm in vitro bonding between the two components of the composite is a necessary condition to validate this model. Our study demonstrated a gross and microscopic integration of the two components and a cartilage-like quality of the newly formed matrix. Moreover, we noticed an improvement of this integration and GAGs production during the in vitro culture.

Greater peripheral blood flow but less bleeding with propofol versus sevoflurane during spine surgery: a possible physiologic model?

Study Design. Prospective, randomized, single blind. Objective. To compare the effects of sevoflurane and propofol on lumbar-paraspinal-muscles regional blood flow, as well as bleeding when controlled hypotension is used. Summary of Background Data. Controlled hypotension is the technique of choice to reduce blood loss during spine surgery, but changes in blood flow occurring to lumbar paraspinal muscles during controlled hypotension with propofol and sevoflurane, as well as the entity of bleeding, are unknown. Methods. Blood flow was assessed by means of a laser Doppler flowmeter during the prehypotensive and hypotensive (defined as a 15% reduction of baseline mean arterial pressure) period in 28 patients (aged 28–73 years, American Society of Anesthesiologists (ASA) I–II) undergoing lumbar spine surgery. Patients were randomized to receive either sevoflurane or propofol as main anesthetic agent to achieve hypotension. At the end of the surgery, blood loss was calculated and intraoperative bleeding (Visual Analogue Scale ranging from 0 to 100) was evaluated by the surgeon. Results. Peripheral Blood flow was significantly greater in the propofol group both before and during the hypotensive period (median values of 32.7 FU vs. 7.7 and 38.5 FU vs. 10.5, respectively). Despite this fact, blood loss and intraoperative bleeding were significantly reduced when propofol had been used (P < 0.05). Conclusion. Despite the greater blood flow when it is used, propofol causes less bleeding than sevoflurane during spine surgery and could be more indicated to produce hypotension during anesthesia. Moreover, it is possible to explain our findings hypothesizing a selective vasodilation of propofol (postcapillary, venous vasodilation), different from that of sevoflurane (precapillary, arteriolar vasodilation).

Pseudoaneurysm overlying an osteochondroma: a noteworthy complication

Pseuodaneurysms are an extremely rare complication of osteochondromas. We describe a case of traumatic pseudoaneurysm of the brachial artery presenting as a soft tissue mass in a patient who was treated for an osteochondroma 3 years earlier. This case demonstrates that radiographic follow-up of large osteochondromas is mandatory and that, in patients with soft tissue masses and a history of osteochondroma, pseudoaneurysms should be included in the differential diagnosis.

Mammary-type myofibroblastoma of popliteal fossa

Mammary-type myofibroblastoma is a very rare, benign, spindle cell lesion, arising mainly in the inguinal region. This clinical entity strictly duplicates the features of its breast counterpart. To our knowledge, this is the first report of this particular lesion occurring in the popliteal fossa. We discuss the clinical, radiological and histopathological features of this case, emphasizing the role of incisional biopsy in such an unusual neoplasia.

17β-Estradiol positively modulates growth hormone signaling through the reduction of SOCS2 negative feedback in human osteoblasts

Recent evidence demonstrated an interplay between estrogens and growth hormone (GH) at cellular level. To investigate the possible mechanism/s involved, we studied the effect of 17β-estradiol (E2) on GH signaling pathways in primary culture of human osteoblasts (hOBs). Exposure of hOBs to E2 (10(-8) M) 60 min before GH (5 ng/ml) significantly increased phosphorylated STAT5 (P-STAT5) levels compared with GH alone. E2 per se had no effect on P-STAT5. E2-enhanced GH signaling was effective in increasing osteopontin, bone-sialoprotein, and IGF II mRNA expression to a greater extent than GH alone. We then studied the effect of E2 on the protein levels of the negative regulator of GH signaling, suppressor of cytokine signaling-2 (SOCS2). E2 (10(-11) M-10(-7) M) reduced dose-dependently SOCS2 protein levels without modifying its mRNA expression. The silencing of SOCS2 gene prevented E2 positive effect on GH induced P-STAT5 and on GH induced bone-sialoprotein and osteopontin mRNA expression. Treatment with the inhibitor of DNA-dependent RNA synthesis, actinomycin-D, did not prevent E2 induced decrease of SOCS2, thus suggesting a non-genomic effect. E2 promoted an increase in SOCS2 ubiquitination. To determine if increased ubiquitination of SOCS2 by E2 led to degradation by proteasome, hOBs were pretreated with the proteasome inhibitor MG132 (5 μM) which blocked E2 reduction of SOCS2. These findings demonstrate for the first time that E2 can amplify GH intracellular signaling in hOBs with an essential role played by the reduction of the SOCS2 mediated feedback loop.

An in vitro tissue-engineered model for osteochondral repair

One of the main topics of regenerative medicine and tissue engineering is to address the problem of lesions involving articular cartilage. In fact, these lesions do not heal spontaneously and often lead to osteoarthritis, which causes chronic pain and worsens quality of life. Moreover, the only available treatment for osteoarthritis is symptomatic therapy and prosthetic replacement, with far from satisfactory results. A more conservative approach that restores the articular surface and function with a biologic tissue is desirable. Several strategies for regenerating articular cartilage have been proposed and applied in clinical practice but a gold standard has not yet been identified. Biphasic composites are the latest products of tissue engineering applied to articular cartilage and they seem to permit a more efficient integration of the engineered neo-tissue with the host. We present an in vitro tissue engineered model for osteochondral repair based on a composite of chondrocytes-fibrin glue gel and a calciumphosphate scaffold. This composite showed a gross integration of the two components and a cartilage-like quality of the newly formed matrix. Further studies are planned to quantify the adherence between the scaffold and the cellular fibrin glue.