To prevent bone loss, OPG/RANK/RANKL signalling pathway is a key in keeping the balance between the action of osteoblasts and osteoclasts. Aim of this study is to assess the influence of long-term nicotine exposure on bone mineral density (BMD) scores, RANKL and OPG levels of plasma and RANKL and OPG immunoreactivities of tissue in rats. In this study, totally 36 Swiss Albino rats (70±10 g) were used in three groups. Whereas normal drinking water was given for the control group (n:12), 0.4 mg/kg/day and 6.0 mg/kg/day nicotine was added to drinking water for low-dose nicotine (LDN) group (n:12) and high-dose nicotine (HDN) group (n:12), respectively for 12 months. At the end of 12^th month, BMD scores were measured via X-ray absorptiometry and then bone turnover was assessed via measuring both RANKL, OPG levels in plasma and RANKL, OPG immunoreactivities in tail vertebrae of all rats. Lumbar spine and femoral regions BMD scores of the control group and the nicotine groups were not significantly difference. In HDN group, OPG levels of plasma were found significantly higher when compared with the control and LDN groups (p=0.001) unlike RANKL levels of plasma. RANKL and OPG immunoreactivities of tissue were found significantly lower in both LDN and HDN groups (p<0.001, p=0.004, respectively) in comparison to control group. No correlation was found between plasma levels and tissue immunoreactivities of RANKL and OPG. As a result, this study indicates that nicotine is not primarily responsible for the decline of BMD frequently seen in smokers.

Purpose: Intraarticular use of anaesthetic agents is common for postoperative pain relief after arthroscopic knee surgery. In this study, we have evaluated and compared the effects of Bupivacaine, Levobupivacaine and Tramadol both invivo and invitro experimental rat models on articular cartilage and chondrocytes.

Materials and Methods: Invivo Experiment: 1. Injections: Thirty mature Sprague-Dawley rats weighing 230 – 300 g were randomized into 3 groups. Bupivacaine (Group 1), Levobupivacaine (Group 2) and Tramadol (Group 3) were injected into the right knee joints and physiological 0.9% saline into the left. 2. Histopathologic Analysis: The specimens were fixed, decalcified and stained with Hematoxylen and Eosin (H& E) and Toluidin Blue. All slides were examined by the same pathologist, who was blinded to the injectate used in each joint. All samples were evaluated histopathologically according to the recommendation of International Cartilage Repair Society’s osteoarthritis and cartilage histopathology grading and staging system. Invitro Experiment: Articular cartilage cells of the rats were cultured and seeded. Cartilage cell seeded samples (104 cells/mL) were incubated in three different anesthetic agents (0,5%); Bupivacaine, Levobupivacaine, and Tramadol respectively. Cell Titer 96TM Nonradioactivity Cell Proliferation (MTS) assay was used to determine the cell density on the samples.

Results:

Invivo: There were pathologic changes like cartilage hypertrophy, active chronic inflammation with abscess formation, cellular proliferation, focal vertical fissures and focal discontunity on cartilage matrix at superficial zone in all three groups on the drug injected sides. Although those histopathologic findings were not found statistically significant when compared the OARSI grade, OA stage and OA score with the control groups (p> 0.05), statistically significant higher OARSI grade, OA stage and OA scores were detected when compared the Levobupivacaine injected group after 10 days with the Levobupivacaine injected group after 48 hours (p< 0.01 [ p=0.008]).

Conclusion: No report has been appointed comparing the effects of the mentioned three drugs both invivo and invitro. Although chondrotoxicity of Bupivacaine was less harmful than Levobupivacaine and Tramadol, these findings suggest that local anesthetics negatively affect articular cartilage and chondrocytes. Given that chondrocyte loss has been implicated in the development of chondrosis and osteoarthritis, orthopaedic surgeons should be careful in their preference for pain control with intraarticular drug injections after arthroscopic procedures.

Purpose: The aim of this study was to redefine the localization of the thenar motor branch (TMB) of the median nerve in relation to the surface landmarks which are in routine use.

Methods: The study was performed in 37 hands of 34 patients who underwent carpal tunnel release. All of the patients were women and the mean age was 50 (35–67). A radiological marking technique was used to determine the localization of the TMB, the middle finger radial side line and the Kaplan’s cardinal line. For marking TMB a circumscribing soft radioopaque yarn was used while the surface landmark lines were demonstrated by taping one K-wire for each. An image intensifier print image was obtained for each case and the distances between the markers of the TMB and the wires were measured.

Results: The TMB had a mean ulnar offset of 12.6 mm (4.0–19.7) from the middle finger radial side line and located 4.4 (0–9.5) mm proximal to the cardinal line.

Conclusion: During the carpal tunnel release operations one must pay more attention to the localization of the TMB of the median nerve because it was found to be 12.6 mm ulnar than that was described in classic literature.