Tension band wiring of the olecranon: is it really a dynamic principle of osteosynthesis?

The tension band principle as applied to transverse olecranon fractures fixed by tension band wiring is based on the premise that distraction forces on the outer cortex of the ulna during elbow flexion are converted to compression forces on the articular surface of the olecranon at the fracture site. In view of some clinical outcomes, where hardware failure and secondary dislocations occur, the question arises if the dynamic compression theory is correct. Compressive forces during active flexion and extension after tension band wiring of a transverse osteotomy of the olecranon were measured in 6 fresh frozen human cadaveric models using a pressure-sensor in the osteotomy gap. We could collect 30 measurements during active flexion and 30 during active extension. Active flexion did not cause any compressive forces in the osteotomy gap. Extension with the humerus in an upright position and the elbow actively extended causes some compression (0.37-0.51 MPa) at the articular surface comparing with active flexion (0.2 MPa) due to gravity forces. Posterior, there was no significant pressure difference observed (0.41-0.45 versus 0.36-0.32 MPa) between active flexion and extension. The tension band wiring principle only exists during active extension in a range of 30-120° of flexion of the elbow. Postoperative exercise programs should be modified in order to prevent loss of compression at the fracture site of transverse olecranon fractures, treated with tension band wiring when the elbow is mobilised.

Footprint reconstruction in a rotator cuff tear associated cyst of the greater tuberosity: augmented anchorage

Tears of the rotator cuff (RC) complicated by bone cysts at the footprint might represent a challenge for the shoulder surgeon. This might be additionally aggravated in elderly patients with inferior bone quality due to osteopenia or osteoporosis. In this report we present a technique for open repair of RC tears by augmenting the cystic lesion at the greater tuberosity using bone void filler in combination with a double row anchor reconstruction technique. Despite disadvantageous position and size of the cyst, using this technique the footprint can be restored by obtaining an anatomical position of the supraspinatus tendon. The application range of this technique is not limited to defined bony defects and presents a promising novel surgical approach. Level of evidence V.

Use of the fulcrum axis improves the accuracy of true anteroposterior radiographs of the shoulder

In 100 patients the fulcrum axis which is the line connecting the anterior tip of the coracoid and the posterolateral angle of the acromion, was used to position true anteroposterior radiographs of the shoulder. This method was then compared with the conventional radiological technique in a further 100 patients.

Three orthopaedic surgeons counted the number of images without overlap between the humeral head and glenoid and calculated the amount of the glenoid surface visible in each radiograph. The analysis was repeated for intraobserver reliability. The learning curves of both techniques were studied.

The amount of free visible glenoid space was significantly higher using the fulcrum-axis method (64 vs 31) and the comparable glenoid size increased significantly (8.56 vs 6.47). Thus the accuracy of the anteroposterior radiographs of the shoulder is impaired by using this technique. The intra and interobserver reliability showed a high consistency. No learning curve was observed for either technique.

Cerebrospinal s100-B: a potential marker for progressive intracranial hemorrhage in patients with severe traumatic brain injury

OBJECTIVE

Traumatic brain injury (TBI) is associated with cerebrovascular dysfunction and changes of the blood-brain barrier (BBB) function. Although knowledge about the function of the BBB would be of high interest, non-invasive neurodiagnostic tools are still lacking. In this context it has been shown, that the astrocytic protein S100-B is a significant parameter for neuronal damage. However, there is only poor knowledge about the dynamics of S100-B in cerebrospinal fluid (CSF) and serum of patients with severe TBI. Therefore, the aim of this study was to analyze intrathecal and systemic concentrations of S100-B in patients with severe TBI in correlation to the development of progressive intracranial hemorrhage (PIH) as well as to the CSF/serum albumin ratio (Q subsetalb), as functional parameter of the BBB.

PATIENTS AND METHODS

In patients, suffering from severe TBI (GCS =or<8pts) and respectively healthy control patients, albumin for calculating the CSF/serum albumin ratio (Q subsetalb) as well as S100-B protein were analyzed in CSF and serum. Samples were collected immediately after placement of a ventricular catheter and 12h, 24h, 48 h and 72 h after TBI. S100-B was quantified using Elecsys S-100 superset assay (Roche superset Diagnostics; Mannheim, Germany). Volume measurements of focal mass lesions based on CT images taken during the first 72 h after TBI were obtained according to the Cavalieri's Direct Estimator method.

RESULTS

21 TBI-patients and respectively 10 healthy controls were enrolled. In patients exhibiting a mean ICP >15 mmHg (n = 15) CSF levels of S100-B were significantly increased on admission (819 +/- 78 pg/ml) compared to patients with ICP =or<15 mmHg (n = 6, 175 +/- 12 pg/ml) as well as to the control group (n = 10, 0.8 +/- 0.09 pg/ml). In the group with ICP >15 mmHg 8 patients developed PIH A positive correlation was found between CSF S100-B and ICP (r2 = 0.925, p<0.001). Furthermore a positive correlation between serum S100-B and Q subsetalb was found for each sampling point (r superset2 = 0.793, p<0.001).

CONCLUSIONS

The cerebrospinal and serum concentration of S100-B in patients with severe TBI was evaluated. Monitoring cerebrospinal S100-B might help to prospectively identify patients with PIH.

Cerebrospinal IL-10 concentration is elevated in non-survivors as compared to survivors after severe traumatic brain injury

OBJECTIVE

The intrathecal posttraumatic inflammation contributes to secondary brain damage as well as to the induction of neuroreparative mechanisms. In this context release of interleukin-10 (IL-10) has been reported to play a major role. However, initial IL-10 concentration in CSF remains incompletely characterized. Therefore, the aim was to analyze Il-10 in CSF and serum of patients early after TBI.

METHODS

For control, 10 volunteers receiving spinal puncture were enrolled. In patients with severe TBI (GCS<8 pts.), CSF and serum was drawn within 90+/-45 min after intraventricular catheter insertion (0 h), as well as 12 h, 24 h and 48 h after TBI. Albumin for assessing Blood-Brain-Barrier (BBB) function and IL-10 (IMMULITE, DPC Biermann, Bad Nauheim, Germany) were analyzed.

RESULTS

23 patients were enrolled. 15 survived and 8 deceased within 24h. In controls, CSF IL-10 was below detection limit (<5 pg/ml). In contrast, IL-10 was elevated significantly in non-survivors at 0 h vs. survivors and controls (30+/-6 vs. 9+/-1 vs. <5 pg/mL). This was accompanied by a significant increase of serum IL-10 in both groups at 0 h vs. controls (survivors: 30+/-6 pg/mL, non-survivors: 48+/-8 pg/mL, controls: 10+/-7 pg/mL, p<0.001). Survivors revealed signs of a mild BBB dysfunction during the entire observation period. In contrast, non-survivors presented a severe BBB breakage.

CONCLUSIONS

We demonstrated an analysis of IL-10 CSF and serum concentration after TBI. These data support an intrathecal IL-10 synthesis. Although the significant increase of IL-10 might indicate a bad outcome of TBI, responsible mechanisms still have to be elucidated.

Stage-dependant management of septic arthritis of the shoulder in adults

Diagnostic and therapeutic standards relating to septic conditions of the shoulder are rarely documented in the literature. For this study, patients suffering from septic shoulder arthritis were prospectively enrolled. Staging was based on the criteria of Gächter (Stutz et al., Knee Surg Sports Traumatol Arthrosc 8:270-274, 2000), and assessment of functional outcome was based on a self-assessed Constant score (Boehm et al., Unfallchirurg 107:397-402, 2004). Patients were separated into three groups according to the CEBI-classification reported by Pfeiffenberger and Meiss (Arch Orthop Trauma Surg 115:325-331, 1996). Forty-three patients were enrolled. Group I contained 21% of patients, while 23% were assigned to group II, and 56% to group III. Staphylococcus aureus was found in 71%. Eight patients were treated arthroscopically, and 35 received open surgery. None of the implants could be preserved. The mean self-assessed Constant score after 26 +/- 7 months was 74 +/- 9 points in group I, 63 +/- 14 points in group II, and 53 +/- 14 points in group III. Diagnostic work-up consisted of laboratory analysis including CRP and joint aspiration. Arthroscopic procedures can be effective when implemented early. With regard to implants and chronic symptoms, primary removal should be critically reconsidered.

Zweizeitige bilaterale Klavikulafraktur

In this case report we present treatment strategies and the functional and cosmetic outcome in a case of midclavicular fractures. A 20-year-old patient suffered from nearly identical fractures of the left and right clavicle with a time interval of 2 years following snowboard falls. The first fracture was treated conservatively leading to an unsatisfactory course and result. This was the reason why 2 years later the contralateral fracture was treated by intramedullary nailing using an elastic titanium nail. The functional and cosmetic outcome of this treatment was excellent. In cases of clavicular fractures elastic stable intramedullary nailing (ESIN) is a minimally invasive technique leading to fast analgesia resulting in a high level of mobility and ultimately a pleased patient. If the indication is right, intramedullary nailing can be a helpful operation technique which complements the already established procedures (conservative and plate osteosynthesis) in cases of dislocated clavicular fractures.

Operative treatment of greater tuberosity fractures of the humerus--a biomechanical analysis

BACKGROUND

Fractures of the greater tuberosity of the humerus present with increasing frequency. However, no biomechanical data about the optimal fixation technique of greater tuberosity fractures is available. This biomechanical cadaver study compares the stability of three standard fixation techniques used for the treatment of greater tuberosity fractures of the proximal humerus.

METHODS

In 21 fresh frozen proximal humeri, standardized fractures of the greater tuberosity were created. The specimens were randomly assigned to one of three operation techniques: wire tension banding, two cancellous screws and transosseous sutures. These constructs were mechanically tested by applying an increasing force to the supraspinatus tendon. Load to 5mm displacement (load to 5mm yield point) and load to failure (maximum stretch strength) were measured in Newton (N).

FINDINGS

Load to 5mm yield point values showed no significant differences between tension banding (498 N, SD 153) and two cancellous screws (400 N, SD 174) (P>0.01). Both techniques showed significantly higher values than transosseous sutures (185 N, SD 132) (P<0.01). Load to failure values were significantly higher for tension banding (1054 N, SD 125) than screws (842 N, SD 140) and sutures (480 N SD 101) (P<0.01). The difference between screws and sutures was also significant (P<0.01).

INTERPRETATION

Tension banding and two cancellous screws provided the strongest fixation for isolated fractures of the greater tuberosity.

Diagnostik und Behandlungsregime der traumatischen dorsalen Schulterluxation

In contrast to anterior dislocations, traumatic dorsal shoulder dislocation is a rare complication of upper extremity injuries. If the diagnosis is overseen and treated incorrectly, severe mobility restrictions might be the consequence for the injured individual. Hence, the aim of this article is to demonstrate the adequate diagnostic and therapeutic management and to critically discuss the literature.

Die winkelstabile Osteosynthese am proximalen Humerus mit der PHILOS-Platte

BACKGROUND

Proximal fracture of the humeral head is the third most frequent fracture in humans. Most (70%) of those affected are over 60 years old. It is hoped that advanced locking medullary screws or plates will reduce the risk of secondary dislocation of screws or fracture segments when the bone of the humeral head is osteoporotic.

METHODS

From January 2002 to August 2005, 225 displaced humeral head fractures in 223 patients aged on average 66+/-15 years were treated with a new locking proximal humeral plate.

RESULTS

In 176 patients in whom follow-up was possible, the average Constant Score after 9 months was 70+/-19 points (raw data), or 81+/-22% in the normalized score. No significant difference was detected between the younger group up to 65 years of age (73% points) and those over 65 years of age (80% points). Axial deviations by more than 30 degrees were noted in 11 (5%), and of 159 displaced tubercles, malreduction by more than 5 mm was noted in 14 (9%). Two infections and two haematomas had to be treated so far. Primary screw perforations were seen in 24 (11%) cases as well as further implant dislocations in 3 (1,7%). Plate dislocations out of the shaft existed in 4 (2,4%) and 14 collapses of the humeral head with secondary screw perforations were recorded. All other complications arose out of technical faults, such as 24 screw perforations (11%) into the glenohumeral joint and 3 (1.7%) cases of secondary implant dislocation from the humeral head and 5 (3%) from the shaft, and 14 (8%) sinterings with glenohumeral screw perforation. So far, in addition to 1 case of pseudarthrosis with a broken plate, 5 (3%) cases of total and 9 (5%) of partial avascular humeral head necrosis have been observed.

CONCLUSION

The new implant provides superior stability in the fixation of humeral head fragments and has proved its worth in everyday clinical practice when additional indirect fixation of the tubercle is needed, as it frequently is in elderly patients.

Effects of verapamil on acute murine Chagas' disease

Continuous administration of verapamil significantly reduced the mortality rate of acute murine Trypanosoma cruzi infection (P < 0.05). The mechanistic basis for these observations was investigated. Verapamil and other calcium-channel blockers did not inhibit the growth of epimastigotes in culture. Furthermore, verapamil did not inhibit the intracellular growth of amastigotes in endothelial cells as determined by the uptake of 3H-uracil. There were no significant differences in parasitemia between infected mice that were untreated and those treated with verapamil. Twenty days postinfection infected, untreated mice had a parasitemia of 5.8 x 10(6) trypomastigotes/ml (SD +/- 2 x 10(6)), whereas infected, verapamil-treated mice had a parasitemia of 2.2 x 10(6) trypomastigotes/ml (SD +/- 0.5 x 10(6)). There was no significant difference in mortality between mice administered verapamil only for the initial 10 days of murine infection compared to those treated continuously. A 3-day delay in the initiation of verapamil administration reduced the mortality rate, but a 10-day delay did not. Propranolol (beta-adrenergic blocker), prazosin (alpha 1-adrenergic blocker), and diltiazem (another calcium-channel blocker) reduced the mortality but not significantly (P = 0.07). In biochemical studies of the beta- adrenergic signal transduction complex, we determined that verapamil and propranolol reversed the infection-associated decrease in myocardial beta- adrenergic adenylyl cyclase activity. In contrast, complementary western blot analysis revealed no significant changes in the G-proteins of the beta- adrenergic receptor complex 45 days postinfection. Therefore, these results suggest that the basis of verapamil's influence on the early critical period of infection is multifactorial and independent of a direct trypanocidal effect.

Effects of persistent lymphocytic choriomeningitis virus infection on cholinergic neurons in the mouse

We have examined the effects of persistent infection with the Armstrong E350 strain of lymphocytic choriomeningitis virus (LCMV) on choline acetyltransferase activity in several regions of Balb/c mouse brain. Despite the presence of high titres of virus in brain for as long as 6 months, and a widespread distribution of virus antigen, no decreases in choline acetyltransferase activity could be demonstrated. The enzyme activity was increased in some regions of brain, showing an effect of the persistent virus infection on a differentiated cell function. Although these data do not suggest a role for LCMV in human neurologic disease, similar studies may allow useful animal models to be conveniently and reproducibly generated.

Trypanosoma cruzi: inhibition by spirogermanium hydrochloride

Spirogermanium is an antineoplastic agent that has been shown to be useful for the treatment of a variety of solid tumors and Plasmodium falciparum infection. We found that this agent, at concentrations of 1-10 micrograms/ml, markedly inhibited the growth of epimastigotes of Trypanosoma cruzi. This inhibition of growth was seen in liver infusion tryptose cultures as well as on agar where colonial growth was inhibited markedly. Ultrastructural studies demonstrated that affected organisms were round and swollen and contained vacuoles, lamellar structures, and multivesicular bodies. Spirogermanium also significantly decreased the growth of intracellular amastigotes in myotubes. Pretreatment of myotubes with the agent protected them from infection with trypomastigotes but tachyzoites of Toxoplasma sp. readily infected pretreated cells. These data suggest that spirogermanium may be useful as a chemotherapeutic agent against T. cruzi.

Preliminary study on the suppression of experimental autoimmune encephalomyelitis in the Lewis rat with spirogermanium

Spirogermanium (SG) is an azaspirane compound that incorporates the element germanium into a heterocyclic ring structure. It is currently being tested in phase II clinical trials as an anti-neoplastic agent and, in experimental animals, has suppressed adjuvant arthritis. In this study, SG suppressed experimental autoimmune encephalomyelitis in the Lewis rat. Suppression was a dose-dependent phenomenon and doses of 28 mg/kg and 40 mg/kg given intraperitoneally five through 14 days postinoculation gave significant protection. Perivascular inflammation in the central nervous system was also suppressed in animals receiving effective doses. Although these doses were well tolerated, cytoplasmic lamellar-bodies were found in the central nervous system of all SG-treated animals. Also, animals treated with SG developed diarrhea and weight loss, although histologic study of the gastrointestinal tract revealed no lesions.

Acetylcholinesterase levels in skeletal muscle of mice infected with Trypanosoma cruzi

Acetylcholinesterase (AChE) activity was measured in skeletal muscle from susceptible (A/J) and resistant (C57BL/6) mice infected with the Brazil strain (myotropic) of Trypanosoma cruzi. There was a 60% decrease in activity in skeletal muscle obtained from A/J mice 20 days post-infection as compared to controls. There was no decrease in AChE activity in skeletal muscle obtained from infected C57BL/6 mice 20 and 150 days post-infection. Histologic examination of skeletal muscle from infected A/J mice revealed marked necrosis, pseudocysts, and minimal inflammation. Similar examinations in C57BL/6 mice revealed marked inflammation in the absence of necrosis and parasites. These data provide additional biochemical support that denervation hypersensitivity is an important concomitant of Chagas' disease and that it is already present during the acute stage. Additionally, it may support the notion that the presence of the parasite mediates these abnormalities.