We describe the use of the Leeds-Keio ligament to reconstruct a neglected quadriceps tendon rupture following revision knee arthroplasty. The Leeds-Keio ligament has been used in the treatment of patellar tendon ruptures complicating primary knee arthroplasty with good result--but may, as this report shows, also be successfully applied to address deficiencies of the quadriceps tendon in the revision setting, with continued good function for 2 years.

On analysis, the data collection system was revealed to be flawed. Grade 1 areas (erythema with no ulceration) were included, leading to a dramatic discrepancy between reported and confirmed pressure sores. Re-analysis showed the confirmed pressure sore rates to be much lower (2.3% NHS, 1.0% private hospital). Conclusions: This audit suggests that both poor data collection and education lead to inaccurate audit. This may lead to subsequent inappropriate management and inappropriate NHS star ratings.

Impaction allograft as a scaffold for bone-forming cells is a tissue-engineering approach for filling bone defects that are commonly encountered during revision total joint replacement (THR). The purpose of this in vitro study is to assess the viability of mesenchymal stem cells (MSC) grown on allograft following impaction using forces similar to those measured during revision total hip replacements. Impaction forces of 0, 3, 6, and 9 kN were used representing normal and high impact. The results showed that the viability in the 3 and 6 kN groups was not significantly reduced compared with that of the 0 kN group, while the survival of the MSCs was significantly reduced after 9 kN impaction force. This study suggests that the addition of MSCs to the allograft scaffold will survive normal impaction force in revision THR.

Tissue engineering approaches for bone blocks previously have used synthetic scaffolds. Bone graft (allograft) is used to fill bone defects, but standard processing can lessen this scaffold's osteoinductive potential. We wanted to test if allografts could be used to produce a viable bone block using mesenchymal stem cells. We hypothesized that mesenchymal stem cells differentiate into osteoblasts producing extracellular matrix when cultured on allografts. We also hypothesized that the addition of osteogenic supplements would increase the rate of differentiation. To test these hypotheses, mesenchymal stem cells were isolated from bone marrow aspirated from 10 patients and cultured on allografts from five donors (Group 2), producing 50 samples. This was repeated on allografts heat-treated to denature bioactive proteins (Group 1), and repeated again on allografts to which osteogenic supplements (Group 3) were added. Group 2 mesenchymal stem cells differentiated into osteoblasts producing higher levels of alkaline phosphatase, osteopontin, and Type I collagen matrix protein than Group 1. The rate of differentiation of Group 3 mesenchymal stem cells increased with the supplements. Overall, it was established that the bioactive proteins in the allograft stimulated mesenchymal stem cell differentiation into osteoblasts, with production of extracellular matrix, and that this differentiation increased with the addition of osteogenic supplements.

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Dart thrower's motion is the functional coupled movement of the wrist from radial extension to ulnar flexion. The aim of this study was to evaluate dart thrower's motion following three surgeries: radioscapholunate fusion, four-corner fusion and proximal row carpectomy. Six fresh-frozen cadaver forearms were dissected. Sequential loading of tendons resulted in radial extension and ulnar flexion allowing dart thrower's motion measurements at end range before and then again after each surgery. After radioscapholunate fusion, 74% of both radial extension and ulnar flexion were maintained. After four-corner fusion, radial extension decreased to 53% and ulnar flexion to 84% of control motion. Proximal row carpectomy did not statistically significantly alter radial extension, but decreased ulnar flexion to 87%. We found that dart thrower's motion is well maintained in three of these commonly used surgical treatments. These results may aid surgeons in managing patients by providing comparative functional movement following these procedures.

The purpose of this study was to determine the alignment of the normal trapeziometacarpal joint and any changes in its alignment with age. Radial, dorsal and dorsoradial subluxation were measured on computerized tomographic scans in 50 joints of 50 adults aged 18 to 62. There were statistically significant correlations between increasing age and dorsoradial subluxation but no significant correlation with dorsal and radial subluxation. Significant dorsoradial subluxation occurs after 46 years of age in the normal trapeziometacarpal joint. A mean dorsoradial subluxation of 21% (range 14%-30%) can be considered normal in this age group.