Introduction

Neck-stem corrosion has been associated with Adverse Local Tissue Reaction (ALTR) in dual-taper femoral stems. Several diagnostic tests, of varying specificity and sensitivity, are used to identify ALTR. The purpose of this study was to document the clinical presentation, diagnostic workup and surgical findings in a large cohort of patients with dual modular stems, and use this information to propose an evaluation protocol that assists surgical decision-making.

Although reverse total shoulder arthroplasty (TSA) may restore shoulder abduction and forward flexion in the setting of a massive rotator cuff tear, the ability to use the extremity for ADL’s is often limited by external rotation weakness. Even though the reverse TSA restores abduction, the patient may be unable to bring the hand to his or her mouth because with the elbow flexed the weight of the hand causes the shoulder to fall into internal rotation. Concomitant transfer of latissimus dorsi (LDT) to the posterior greater tuberosity is a solution advocated by some surgeons. It is hypothesized that this inferiorly-directed force partially counteracts the superiorly-directed force of the deltoid, resulting in decreased shear forces on the glenoid baseplate-bone interface.

Three cadaver shoulder specimens were dissected and implanted with the reverse TSA. The rotator cuff was completely released to simulate a massive rotator cuff tear. Each shoulder was mounted in a shoulder controller that simulates neuromuscular control and replicates in vivo glenohumeral kinematics. The controller utilizes an optical, three dimensional tracking system. The humerus was weighted to simulate the full mass of the upper extremity and stepper motors were connected to the insertion points of the anterior, middle and posterior divisions of the deltoid by Spectra^® cord. Simulated active abduction in the scapular plane was performed using position closed-loop feedback control. The joint reaction force at the glenosphere was measured at 5° intervals from 30°–70°. A fourth stepper motor was then connected to the greater tuberosity with 2.73kg applied to simulate a LDT and the test was repeated. Five trials were performed under each condition. Four-factor ANOVA statistical analysis with Bonferroni correction and α = 0.05 was performed.

After simulated LDT the JRF demonstrated an increase in magnitude at abduction angles between 30° and 65° inclusive (p=0.033). The superiorly-directed shear force was significantly decreased as a result of the LDT between 45° and 70° (p< 0.0001). The compressive component of the JRF was increased for all abduction angles (p=0.025). The force required to achieve abduction increased for the middle deltoid (p=0.035) and anterior deltoid (p=0.036) for the simulated LDT condition at all abduction angles. The posterior deltoid force required for abduction decreased at all abduction angles (p=0.031).

In this model of reverse total shoulder arthroplasty concomitant transfer of latissimus dorsi decreased the superiorly-directed shear force. In addition to providing improved external rotation strength, these lower shear forces may have a protective effect on baseplate fixation by reducing the risk of failure in shear. This may provide additional justification for the transfer. Although superior shear was decreased, total JRF was increased as a result of an increase in the compressive component. Further investigation is needed to determine the potential gain in joint stability and whether the glenoid bone can support such elevated compressive forces. Additionally, the force required in the anterior and middle deltoid was increased after the LDT. This indicates the need for sufficient deltoid strength and rehabilitation.

Introduction: There is an increasing tendency for internal fixation of proximal metaphyseal fractures. Intra-medullary nailing only recently has been considered to be a valuable option in these cases. Through the development of new reliable implant types, nailing finds increasing acceptance.

Questions: Is intramedually nailing with a new angle stable titanium nail a safe procedure in the treatment of proximal humeral fractures and is it combined with a good outcome?

Material and methods: A prospective international mul-ticenter study with standardized study control focused on the “Proximal Humeral Nail (PHN–Synthes Inc.), possible complications and clinical outcome. 151 fractures had been treated in 11 hospitals, where 72 were A-type, 67 B-type and 12 C-type (AO). There were 37 male, 114 female patients, median age 66 years ranging from 16 to 97 years. The outcome had been measured through Constant-Morley scores and DASH scores. 108 patients could be followed up until 1 year postoperatively.

Results: Important complications were perforation of the articular surface by screw or spiral blade (n=8), pain due to the implant (n=10), dislocation of fragments (n=2), non union (n=2), humeral head necrosis (n=3) and wound infection (n=1). The Constant-Morley score shows in total mean values one year postoperatively 75.3 in the injured and 89.9 in the non-injured side. The DASH score pre-operatively was in total 5.9 and 9.3 one year postoperatively, where the best results could achieve 0 points, the worst 100 points.

Discussion: Analyzing the complications, perforation of the articular surface by screw or spiral blade and pain due to the implant or impingement at the nail base are clearly related the technical failure in performing nailing. Here or the nail has not been introduced profoundly enough or the length for the spiral blade was not determined exactly and probably not controlled intraoperatively. This is due to the individual accuracy of the surgeon. The development of non-union (2/108) shows a ratio equal or even better to what is reported in conservative treatment or plate osteosynthesis. Dislocation of fragments n the other side, show the limit of this procedure, where in multifragmentary fracture type one spiral blade will not be able to fix a fragments. Using additional hardware is possible, but might reduce the effect of an initially low invasive approach. Constant score and Dash-score results perform similar to plate osteosynthesis, where clearly C-type-fractures present the worst prognosis.

Conclusion: Proximal humeral nailing seems to be beneficial in A-type metaphyseal fractures. Even in many B-type fractures it is still a good alternative with limited incision to the plate osteosynthesis.

In C-type fractures it is not advisable as a standard routine, only for experienced surgeons it might be a possible solution in selected cases.

Introduction: The Expert Tibia Nail was designed to address proximal, shaft, segmental and distal tibia fractures in one implant. Multiple locking options in various directions provide more stability and reduce the risk of secondary malalignment. Angle stable cancellous bone locking screws in the tibia head also improve fixation.

We evaluated this new implant in our series in a prospective, multicenter setting.

Methods: 190 patients were treated in 10 participating centers using the Expert Tibia Nail (Synthes). 127 patients suffered polytrauma, 58 presented as open fractures. Within the framework of the study 5 cases were proximal tibia fractures, 108 shaft fractures, 56 distal fractures, and 21 segmental fractures. These were followed-up postoperatively, after 3 months and one year and evaluated radiologically and clinically with regard to malalignment, union rate and complications.

Results: Non union occurred in 9 cases after one year of follow up (n=150). 20 patients showed delayed union. The rate of open and complex fractures was high in this group. Dynamisation was performed in 10 cases. Valgus/varus and recurvatum/antecurvatum malalignment of more than 5 degrees occurred in 13 cases. Stable reduction was achieved in 144 cases. In 4 complex fractures, initial reduction went into malalignment. 2 patients developed a deep infection after 3rd degree open fractures. 34 patients suffered from pain in the operated area. 6 screws broke during the follow-up.

Discussion: The Expert Tibia Nail proved to be an excellent tool to treat tibia fractures. Not only shaft fractures but also complex fractures in the proximal and distal metaphyseal area can be successfully stabilized due to advanced locking options and design of the nail. The rate of malalignment, non-union and complications was low.