Steen Lund Jensen

Elbow joint kinematics after excision of the radial head

The contribution of the radial head to elbow joint kinematics was studied in 7 osteoligamentous elbow preparations. During unloaded flexion and extension, radial head excision induced a maximum varus displacement of 1.6 degrees with 20 degrees of joint flexion and a maximum external rotation of 3.2 degrees at 110 degrees of flexion. With application of a 0.75-Nm load, radial head excision induced a maximum laxity of 3.3 degrees at 20 degrees of flexion in forced varus and a maximum laxity of 8.9 degrees at 10 degrees of flexion in forced external rotation. No laxity was observed in forced valgus or internal rotation. The results were independent of the rotation of the forearm. This study indicates that the radial head acts as stabilizer to the elbow joint in forced varus and in forced external rotation. The results suggest that fractures of the radial head cannot be treated by simple excision without altering the basic kinematics of the elbow joint.

Elbow joint stability following experimental osteoligamentous injury and reconstruction.

Elbow joint dislocation was simulated in cadaveric specimens to quantify laxity induced by radial head and coronoid process lesions, either alone or in combination with collateral ligament insufficiency. The effects of lateral ligament reconstruction and radial head prosthesis replacement were also considered. Absence of the radial head and the coronoid process induced rotatory laxity of 145% and 128% (both P <.01), respectively, compared with the intact joint. When both were absent, the joints subluxated regardless of collateral ligament status. Isolated radial head prosthesis implantation prevented this subluxation, and laxity almost normalized. Lateral collateral ligament reconstruction prevented major laxity even in the absence of the radial head. Lateral collateral ligament reconstruction and radial head prosthetic replacement yielded restraint against gross instability in the maximal unstable situation (terrible triad). The lateral collateral ligament is the prime stabilizer to external rotation, and reconstruction of this alone, even with an absent radial head, is beneficial.

IT 9302, a synthetic interleukin-10 agonist, diminishes acute lung injury in rabbits with acute necrotizing pancreatitis.

BACKGROUND Proinflammatory cytokines (eg, tumor necrosis factor [TNF]-alpha, interleukin [IL]-1 and Il- 8) are believed to play an important role in the pathogenesis of acute necrotizing pancreatitis (ANP) and its systemic complications. Recently, IL-10 has emerged as a major anti-inflammatory cytokine, inhibiting the secretion and activities of inflammatory cytokines. Further, a protective effect of IL-10 has recently been shown in experimental acute pancreatitis. The purpose of this study was to test the potential role of a newly developed IL-10 agonist, IT 9302, in a model of ANP in rabbits. METHODS ANP was induced in 18 rabbits by retrograde injection of 5% chenodeoxycholic acid in the pancreatic duct, followed by duct ligation. The rabbits were allocated to pretreatment with intravenous physiologic saline solution or IT 9302 (200 micrograms/kg) 30 minutes before the induction of ANP. RESULTS Injection of IT 9302 resulted in a significant reduction in the blood levels of TNF-alpha and IL-8 from 3 to 6 hours. IT 9302 also reduced the amount of ascitic fluid and significantly inhibited neutrophil infiltration and margination, as well as the number of CD11b- and CD18-positive cells in the lung tissues. By contrast, the local pancreatic necrosis, as well as the biochemical changes such as serum amylase, lipase, and calcium, was sever and similar in both groups. Survival was improved significantly after treatment with IT 9302. CONCLUSIONS As expected, IT 9302 cannot change the degree of ANP induced by 5% bile acid but does reduce mortality rates and the development of acute lung injury, probably through the inhibition of circulating levels of TNF-alpha, IL-8, and the expression of the adhesion molecule complex CD11b/CD18.

Systemic and Cell-Mediated Immune Response after Laparoscopic and Open Cholecystectomy in Patients with Chronic Liver Disease

Background: As impaired immune function observed in cirrhotic patients is known to increase the risk of postoperative complications, the immunological response to surgery was investigated. Methods: Twenty-eight patients with postnecrotic liver cirrhosis or chonic hepatitis C and symptomatic gallstone disease were randomly allocated to laparoscopic (LC) or open cholecystectomy (OC). Changes in concentrations of cytokines (TNF-α, IL-1β, IL-6, IL-8 and IL-10) were followed and the effect of surgical trauma on the distribution of lymphocyte subpopulations (CD3, CD4, CD8, CD16 and CD19) and NK cell cytotoxicity were measured. Results: After OC a decrease in circulating CD3 (p < 0.05) and CD4 (p < 0.05) and an increase in CD19 (p < 0.05) cells were detected in contrast to LC after which only CD16 cells decreased (p = 0.05). The number of CD3 cells was higher after LC than after OC (p < 0.01), whereas the number of CD19 cells was higher after OC than after LC (p < 0.01). NK cell cytotoxicity was reduced after LC (p < 0.05). In cirrhotic patients circulating cytokines were unaffected by OC, whereas TNF-α (p < 0.05) and IL-1β (p < 0.05) were reduced after LC. In chronic hepatitis IL-1β decreased after OC (p = 0.05) and IL-10 was significantly higher after LC than following OC (p < 0.05). Conclusion: The immune response is less pronounced after a laparoscopic procedure compared to a conventional approach in patients with chronic liver disease.

Surgical gloves: current problems.

Abstract. One century ago surgical gloves were introduced to practice as part of the new antiseptic technique and originally to protect the hands of the surgeon and his assistants from the harmful dermatologic effects of powerful antiseptics (e.g., carbolic acid) in use at that time. Since then, the wearing of gloves during surgery has been standard practice. Furthermore, the protection value of surgical gloves in preventing cross-infection has stood the test of time. Nevertheless, materials used in glove manufacturing have caused a succession of iatrogenic problems in surgical patients over the years. More recently, emergence of transmissible viruses, such as hepatitis B and C and human immunodeficiency virus, has led surgeons to consider their own safety with the frequent possibility of perforation of surgical gloves by sharp instruments. In this review we discuss the problems associated with surgical glove practice: glove powder-induced peritonitis and adhesions, latex rubber-associated hypersensitivity, and glove perforation.

Protein C activation during the initial phase of experimental acute pancreatitis in the rabbit.

Background: Disturbances of coagulation and fibrinolysis are well-known systemic effects of acute necrotising pancreatitis (ANP). The purpose of this experimental study was to evaluate the initial events in the haemostatic activation during ANP in an animal model with relevance to the human situation. Methods: ANP was introduced in 7 rabbits by infusion of chenodeoxycholic acid in the pancreatic duct. Seven rabbits served as sham-operated controls. Serial measurements of coagulation variables (prothrombin time, activated partial thromboplastin time, FVII activity, fibrinogen, tissue factor activity), anticoagulant proteins (protein C, antithrombin) and fibrinolytic factors (tissue plasminogen activator, plasminogen activator inhibitor-1) were performed for 5 h. Results: ANP was confirmed by elevated serum amylase, development of ascites, and histological changes of the pancreas. A moderate activation of the coagulation system was found in both study groups. A significant decrease in protein C concentration from 1 h after the induction of ANP was found, whereas the response of antithrombin and the inhibition of the fibrinolytic system were similar in the 2 study groups. Microthrombosis of the lungs or kidneys was found in 2 rabbits with ANP. Conclusion: An immediate activation of protein C is a specific characteristic of the haemostatic activation in ANP in rabbits. This activation has not been described previously and the possible therapeutic implications ought to be studied.

A retrospective study of the association between shortening of the clavicle after fracture and the clinical outcome in 136 patients

BACKGROUND AND PURPOSE The purpose of this retrospective study was to examine the association between shortening of the clavicle after a united midshaft fracture and clinical outcome. Second, the purpose was to compare the results obtained by conservative treatment with either a figure-of-eight bandage or a simple sling. MATERIALS AND METHODS This study included 136 patients with a united, conservatively treated, midshaft clavicle fracture. Mean age was 35 years (range 15-70 years); mean follow-up time was 55 months (range 24-83 months). The shortening of the clavicle was measured on a radiograph including one antero-posterior view of both clavicles on a single film and defined as the difference between the injured and the contralateral clavicle. The clinical outcome was measured using the Constant-Murley Score. RESULTS The mean difference in the Constant-Murley Score between the injured and the contralateral shoulder was 7.3, P<0.001 (95% confidence interval (CI) 5.6; 9.1). Mean shortening of the injured shoulder was 11.6mm, P<0.001 (95% CI 10.2; 13.0). A shortening of more than 20mm was not associated with a poorer clinical outcome. The results obtained by conservative treatment with either a figure-of-eight bandage or a simple sling showed no difference in shortening or in the Constant-Murley Score. CONCLUSIONS We found that conservative treatment of midshaft clavicle fractures resulted in final shortening and mild reduction of shoulder function. A shortening of 20mm or more was not associated with a poorer clinical outcome. The figure-of-eight bandage and a simple sling were equal treatments of midshaft clavicle fractures.

Laxity of the elbow after experimental excision of the radial head and division of the medial collateral ligament. Efficacy of ligament repair and radial head prosthetic replacement: a cadaver study.

We studied the stabilising effect of prosthetic replacement of the radial head and repair of the medial collateral ligament (MCL) after excision of the radial head and section of the MCL in five cadaver elbows. Division of the MCL increased valgus angulation (mean 3.9 +/- 1.5 degrees) and internal rotatory laxity (mean 5.3 +/- 2.0 degrees). Subsequent excision of the radial head allowed additional valgus (mean 11.1 +/- 7.3 degrees) and internal rotatory laxity (mean 5.7 +/- 3.9 degrees). Isolated replacement of the radial head reduced valgus laxity to the level before excision of the head, while internal rotatory laxity was still greater (2.8 +/- 2.1 degrees). Isolated repair of the MCL corrected internal rotatory laxity, but a slight increase in valgus laxity remained (mean 0.7 +/- 0.6 degrees). Combined replacement of the head and repair of the MCL restored stability completely. We conclude that the radial head is a constraint secondary to the MCL for both valgus displacement and internal rotation. Isolated repair of the ligament is superior to isolated prosthetic replacement and may be sufficient to restore valgus and internal rotatory stability after excision of the radial head in MCL-deficient elbows.

Revision of failed total elbow arthroplasty with use of a linked implant

We studied retrospectively the results of revision arthroplasty of the elbow using a linked Coonrad-Morrey implant in 23 patients (24 elbows) after a mean follow-up period of 55 months. According to the Mayo Elbow Performance Score, 19 elbows were satisfactory, nine were excellent and ten good. The median total score had improved from 35 points (20 to 75) before the primary arthroplasty to 85 points (40 to 100) at the latest follow-up. There was a marked relief of pain, but the range of movement showed no overall improvement. Two patients had a second revision because of infection and two for aseptic loosening. The estimated five-year survival rate of the prosthesis was 83.1% (95% confidence interval 61.1 to 93.3). Revision elbow arthroplasty using the Coonrad-Morrey implant provided satisfactory results but with complications occurring in 13 cases.

Beneficial Effects of Hydrocortisone in a Model of Experimental Acute Pancreatitis

Background: Proinflammatory cytokines like TNF-α and IL-8 have been thought to play a pivotal role in the propagation of severe acute pancreatitis (AP) and the development of its systemic complications, particularly acute lung injury. Objective: To investigate the effects of pretreatment with hydrocortisone on the production of cytokines and the occurrence of acute lung injury in rabbits with AP. Methods: AP was induced in 17 rabbits by infusion of 5% chenodeoxycholic acid into the pancreatic duct, followed by ductal ligation. The rabbits were allocated to pretreatment with subcutaneous and intravenous hydrocortisone (25 mg/kg, respectively; n = 7) or 0.9% saline (n = 10) 30 min before induction of AP. Rabbits were observed for 12 h. Serum amylase, lipase, TNF-α, IL-8, glucose, calcium and leukocyte count were measured every 3 h. At the end of the experimental period, ascitic fluid was collected and tissue specimens from the pancreas, lungs and kidney were obtained. Results: Hydrocortisone pretreatment improved survival from 40 to 100%. Serum TNF-α and IL-8 were lower in the hydrocortisone group than in the control group at 6 h (p = 0.006 and p < 0.001, respectively). Hydrocortisone abolished leukopenia (p < 0.001), hyperamylasemia (p = 0.05), the occurrence of acute lung injury and reduced the volume of ascites. Conclusions: Our findings suggest a role for TNF-α and IL-8 in mediating the progress of AP from a local disease into a systemic illness. Hydrocortisone should be tested experimentally after the induction of AP and clinically as a prophylactic measure to avoid severe AP induced by endoscopic retrograde cholangiopancreaticography.