Total Elbow Arthroplasty (TEA) is a procedure to treat a number of conditions including rheumatoid arthritis (RA), post-traumatic arthritis, and osteoarthritis. To date, there has been minimal literature published on the Latitude since its release in 2001. There is one study reporting outcomes from the Latitude, a German study published in 2010. The purpose of this study was to analyse outcomes from primary Latitude TEAs.

We performed a retrospective case series of 23 TEAs performed on 20 patients. 6 patients required revision surgery and were not included in the analysis. One patient was lost to follow up, resulting in 17 patients included for ROM analysis. All patients received Latitude TEA through a posterior approach and underwent a standard rehab protocol. 11 Patients were recalled at least two years post-op and were administered DASH and MAYO questionnaires. Complications such as triceps insufficiency, ulnar nerve dysfunction, infection, and aseptic loosening were recorded. Outcomes were compared using the Wilcoxon Signed-Rank test in STATA. Immediate post-op radiographs and patients most recent radiographs were analysed by a blinded upper-extremity surgeon not involved in the initial operation and analysed for loosening and implant malpostioning.

Mean follow up was 4.8 years (range 2.6–7.5 years). Analysis of 17 TEAs in 16 patients revealed no difference in pre-operative ROM and post-operative ROM for flexion (121°±20 vs 129°±16, p=0.13) extension (40°±27 vs 27°±15, p=0.19), pronation (73°±13 vs 75°±24, p=0.55) or supination (64°±22 vs 68°±14, p=0.52). Patients who underwent TEA for RA had a significant improvement in flexion (121°±15 vs 135°±10, p<0.02). There was a statistically significant improvement in flexion-extension arc post-operatively (101°±28) compared to pre-operative scores (83±23 degrees, p<0.02). DASH and MAYO scores were calculated from 11elbows in 11 non-revision patients able to return for examination. The average MAYO score was 87.9 with nine patients in the “excellent” category, two patients in the “good” category, one patient in the “fair” category, and one in the “poor” category. The average DASH score was 32.9. Two patients underwent revision for periprosthetic fractures, two patients underwent revision for infection, one underwent revision for aseptic loosening and two for radial head dissociation (rate of 30%).

This is one of the first studies examining the outcomes of the Latitude TEA. This retrospective case series demonstrates that the Latitude TEA has promising outcomes with respect to improving patient pain and functioning as assessed by the MAYO. Treatment using the Latitude TEA results in favorable functional outcomes for a majority of patients and offers an improvement in flexion-extension arc. Furthermore, our results are comparable to the MAYO scores reported by other studies analysing different prosthesis designs. The complication rate in our series was comparable to published rates of 20–40%.

Purpose: Differentiation of BM-MSCs into adult chondrocytes represents a complex physiological mechanism and full characterization of each individual stage through which the BM-MSC differentiate into adult chondrocytes is not yet understood. The physiological micro-environment of the chondrocytes is intensely hypoxic which triggers over-expression SLC2A proteins (GLUTs) in their membranes as a compensatory mechanism for energy production within the glycolytic cycle.

Method: We cultured and differentiated BM-MSC, and adult chondrocytes in hypoxic (5% O2 tension) and normoxic (20% O2) conditions. Within this cell populations we screened for the presence of the 12 GLUT genes as well as quantification of the variation of the 12 GLUTs gene translation by simple pcr and rt-pcr. The expression profile of the GLUT proteins was investigated using western blot analysis and immunohistochemistry. Functional characterization of the GLUTs expressed in the different cell populations was carried out by the means of radio-isotope labeled hexose fluxes done accordingly to the substrate specificity and kinetic properties particular to each SLC2A isoforms.

Results: Our data showed that the functional genotype and phenotype of the adult chondrocyte and hypoxic BM-MSC comprised an extensive expression of fructose-transporting GLUTs as opposed to the glucose-only transporting isoforms expression in normoxic BM-MSC. The flux data showed clear similarities in functional GLUT profiles between BM-MSC cultured in hypoxic conditions, adult chondrocytes. Investigation of the uptake of a panel of five individual sugars (glucose, fructose, 2-deoxy-gluose, 3-orthomethyl-glucose and galactose) in these cellular populations under both hypoxic and normoxic conditions and in the presence and absence of Cytochalasin B (a GLUT1-specific inhibitor) showed that SLC2A class II transporters (GLUTs 5, 7, 9 and 11) play a more important role in the uptake of sugars by the normal hypoxic chondrocytes when compared to the ubiquitously-expressed GLUT1.

Conclusion: Use of this approach allows the correct culturing conditions to be identified that would select for those chondrocyte precursors from the total BM-MSC population that would have the best potential for producing viable articular cartilage. In addition, specific substrates for GLUTs isoforms could be used for physiologic, non-invasive and real time imaging of cartilage, BM-MSC and cartilage autograft by means of Positron Emission Tomography.