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Carpal coalition is a rare condition caused by a failure in the process of apoptosis. It is often incidentally diagnosed and seldomly symptomatic. The lunotriquetral joint is the most commonly affected joint, accounting for 90% of carpal coalitions. Minnaar classified the lunotriquetral coalitions into 4 types based on their type, extent, and associated abnormalities. Accurately classifying the coalition requires advanced imaging, and we show an example that includes 2-dimensional and 4-dimensional computed tomography and magnetic resonance imaging. Management of carpal coalitions include nonoperative and operative management. Splinting, anti-inflammatory drugs, hand therapy, activity modification, and steroid injections are all examples of nonoperative management. Operative management of coalitions in the carpus has historically been an arthrodesis whereas in the tarsal bones the gold standard is resection. Arthrodesis has a high complication rate and reduces wrist range of motion, whereas resection retains range of motion and allows the patient to return to activity sooner. We present 2 techniques of treating symptomatic carpal lunotriquetral coalition with arthroscopic resection.

This dissertation presents a discussion of blocky and randomly functionalized sulfonated syndiotactic polystyrene copolymers. These copolymers have been prepared over a range of functionalization (from 2% to 10%) in order to assess the effect of the incorporation of these polar side groups on both the thermal behavior and morphology of these polymer systems. The two different architectures are achieved by conducting the reaction in both the heterogeneous gel-state to obtain blocky copolymers and in the homogeneous solution state to obtain randomly functionalized copolymers. In order to compare both the thermal properties and morphology of these two systems several sets of samples were prepared at comparable levels of sulfonation. Thermal analysis of these two systems proved that the blocky functionalized copolymers provided superior properties with regard to the speed and total amount of the crystalline component of sulfonated syndiotactic polystyrene. Above 3% functionalizion the randomly functionalized copolymer was no longer able to crystallize, whereas, the blocky functionalized copolymer is able to crystallize even at a functionalization level of 10.5% sulfonate groups. When considering the morphology of these systems even at low percentages of sulfonation it is clear that the distribution of these groups is different based on the amplitude of the signal measured by small angle x-ray scattering. Additionally, methods were developed to describe both the distribution of ionic multiplets, which varies between blocky and randomly functionalized systems, but also the distribution of crystals. At a larger scale ultra-small angle x-ray scattering was employed to attempt to understand the clustering of ionic multiplets in these systems. Randomly functionalized polymers should a peak that is attributed to ion clusters, whereas blocky polymers show no such peak. Additional studies have also been done to look at the analysis of crystallite sizes in these systems when there are multiplet polymorphs present, it was observed the polymorphic composition is drastically different. All of these studies support that these systems bear vastly different thermal behavior and possess significantly different morphologies. This supports the hypothesis that this gel-state heterogeneous functionalization procedure produces a much different chain architecture compared to homogeneous functionalization in the solution-state. Doctor of Philosophy Polymers are a class of chemicals that are defined by having a very large set of molecules that are chemically linked together where each unit (monomer) is repeated within the chemical structure. In particular, this dissertation focuses on the construction what are termed as "blocky" copolymers, which are defined by having two chemically different monomers that are incorporated in the polymer chain. The "blocky" characteristic of these polymers means that these two different monomers are physically segregated from each other on the polymer chain, where long portions of the chain that are of one type, followed by another section of the polymer that has the other type of monomer. The goal of creating this type of structure is to try to take advantage of the properties of both types of monomers, which can create materials with superior synergistic properties. In this case a hydrophobic (water hating) monomer is combined with a hydrophilic (water loving) chain. This hydrophobic component in the polymer is able to crystallize, which provides mechanical and thermal stability in the material by acting as a physical tether to hold neighboring chains together. With the other set of hydrophilic monomers, which in this case have an ionic component incorporated, we can now take advantage of this chemical components ability to aide in the transportation of ions. Transportation of ions is useful in a variety of commercially relevant applications, two of the most important applications of these ionic materials is in membranes that can be used to purify water or membrane materials in fuel cell technologies, specifically for proton exchange membranes. The focus of this research in particular was to create a simple synthesis technique that can create these blocky polymer chain architectures, which is done by performing the reaction while the polymer is made into a gel. The key to this is that the crystals within the gel act as a barrier to chemical reactions, creating conditions where we have substantial portions of the material that are able to be functionalized and the crystals within the material that are protected from being functionalized. By looking at the thermal characteristics, such as melting temperatures and amount of crystals within these systems we have seen that functionalizing these polymers in the heterogeneous gel state gives substantially better properties than functionalizing these materials randomly. Much like oil and water, incompatible polymer chains will phase separate from each other. In this case the hydrophobic and ionic components will phase separate from each other. The shape and distribution of these phase separated structure will dictate many of the material properties, which can be described by modeling the data collected from x-ray scattering experiments. All of this information will tell us based on the initial conditions that these polymers were created in, what properties should be expected based on the morphology and thermal behavior. This gives a better understanding of how to fine tune these properties based on the structure of the gel and chemical reaction conditions.

The management of complex fractures, dislocations, and fracture-dislocations of the elbow can be challenging. External fixation of the elbow, either static or dynamic, has been used as an adjunctive treatment to stabilize the elbow while allowing the ligaments and fractures to heal. Unfortunately, the complication rate of external fixation has been high.

Background The biceps brachii is the main forearm supinator, which is a direct consequence of its anatomic arrangement. The primary aim of distal biceps rupture is to restore supination strength and function. Cadaveric studies demonstrate that anatomic repairs significantly improve the supination moment when compared to more anterior repairs; however, this has not been tested in the clinical setting. The aim of this study was to compare biomechanical and clinical outcomes of an anatomic repair (Footprint), with a widely used transosseous technique (Endobutton). Methods Twenty-two patients were retrospectively identified from a clinical database (11 Footprint versus 11 Endobutton). Biomechanical performance of strength and endurance for flexion and supination was assessed using a validated isokinetic dynamometry protocol and clinical outcome scores (Quick Disabilities of the Arm, Shoulder and Hand Outcome Measure and the Mayo Elbow Performance Score) were collected for all patients. Results For supination, the Footprint group demonstrated a superior trend for all biomechanical parameters tested. This was statistically significant for mean peak torque, total work of maximal repetition and work in the last third of repetitive testing (p = 0.031, p = 0.036 and p = 0.048). For flexion, the Footprint group demonstrated a superior trend for all biomechanical parameters tested but this was only statistically significant for work in the last third of repetitive testing (p = 0.039). The clinical outcomes were good or excellent for all patients in both groups. Conclusion This study is the first to demonstrate that an anatomic Footprint repair restores superior biomechanical supination strength and endurance compared to a conventional Endobutton technique in a clinical setting. Both techniques, however, provide good or excellent clinical outcomes.

Radiocarpal fusions are performed for a variety of indications, most commonly for debilitating painful arthritis. The goal of a wrist fusion is to fuse the painful, diseased joints and to preserve motion through the healthy joints. Depending on the extent of the disease process, radiocarpal fusions may take the form of radiolunate, radioscapholunate, or total wrist fusions. Surgical techniques and instrumentation have advanced over the last few decades, and consequently the functional outcomes have improved and complications decreased. Techniques for partial carpal fusions have improved and now include distal scaphoid and triquetrum excision, which improves range of motion and fusion rates. In this article we discuss the various surgical techniques and fixation methods available and review the corresponding evidence in the literature. The authors' preferred surgical technique of radioscapholunate fusion with distal scaphoid and triquetrum excision is outlined. New implants and new concepts are also discussed.

To compare the standard Tajima technique for flexor-tendon repair of the hand with three new techniques with respect to strength and technical ease of the repair and bulk at the repair site.A randomized analysis of human cadaver flexor digitorum superficialis tendon repairs.A musculoskeletal research laboratory at a university-affiliated health centre.Thirty-nine fresh-frozen cadaveric flexor digitorum superficialis tendons from index, long and ring fingers harvested and divided transversely. The tendons were randomly allocated for repair by the current standard technique or one of three new techniques.The standard Tajima (modified Kessler) technique, and the Halsted, Savage or Silfverskiold technique.The time to perform each repair, the cross-sectional dimension and the load to failure of the tendon repairs.The Savage repair tolerated the highest loads, followed by the Halsted, Silfverskiold and Tajima repairs. The Silfverskiold technique was the least time-consuming to perform, followed by the Tajima, Halsted and Savage repairs. All of the techniques increased the cross-sectional dimensions of the tendon: the Silfverskiold repair by at least 50% and the Savage repair by over 100%. Although none of the techniques tested performed ideally, all three new techniques provided greater initial static strength than the standard Tajima method.Further in-vitro and in-vivo studies of these new techniques of flexor-tendon repair of the hand are necessary to optimize the treatment of these injuries.

To investigate outcomes after surgical repair of distal biceps tendon rupture and the influence of arm dominance on isokinetic flexion and supination results.While relatively uncommon, rupture of the distal biceps tendon can result in significant strength deficits, for which surgical repair is recommended. The purpose of this study was to assess patient reported functional outcomes and muscle performance following surgery.A sample of 23 participants (22 males, 1 female), who had previously undergone surgical repair of the distal biceps tendon, were re-examined at a minimum of one year after surgery. Biodex isokinetic elbow flexion and supination testing was performed to assess strength (as measured by peak torque) and endurance (as measured by total work and work fatigue). The Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) and Mayo Elbow Performance Scale (MEPS) were used to assess participants' subjectively reported functional recovery.At a mean of 7.6 years after surgical repair, there were no differences between the repaired and uninvolved elbows in peak torque (The long-term strength of the repaired elbow was similar to the uninvolved elbow after surgery to the distal biceps tendon. Endurance of the repaired elbow was similar in flexion but greater in supination, probably influenced by arm dominance.Retrospective case series.Level 4.