Transpedicular screw placement in the cervical spine is difficult, and a high percentage of violations of the pedicle wall occur. This technique should not be used routinely.

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Electrochemical behaviour of [Fe6M2S8-(SR),I3-(M = M o br W) and the roles of molybdenum and tungsten in nit rogenasesREPORTS of the isolation and properties 2 9 3 of the Fe-Mo cofactor of nitrogenase and the structural inferences obtained from extended X-ray absorption fine structure (EXAFS) studies of this molybdenum centre have prompted much synthetic work in pursuit of this entity. Currently, Fe,MoS, cubane-like cluster compounds represent the best synthetic analogues for the molybdenum centre of nitrogenase. In these complexes, Mo is six-co-ordinate where Fe is four-co-ordinate and, in the majority of complexes so far reported, the three ligands attached to the Mo and external to the cube bridge to an identical molybdenum centre. Corresponding systems containing Fe,WS, clusters have also been prepared. Comparisons between these Fe,RloS, and Fe,WS, systems are of interest, not least because W, although incorporated into the FeMo protein of nitrogenase in place of Mo, apparently does not lead to a functional enzyme.The crystal structures of [NEt,],[Fe,MO,S,(SEt),] and [NEt4]3[Fe6W2S8(SEt)9] show that, if Fe,MoS, clusters are valid structural analogues for the immediate molybdenum environment in nitrogenase, there are no steric impediments to W being incorporated into such a site.8 Compounds containing Fe,MS, (M = Mo or W) cubane-

Introduction: Injuries to the medial patellofemoral ligament (MPFL) and patellar tendon in isolation are well-documented entities. There is a paucity of literature describing this combination of injuries and treatment of this concomitant injury pattern.Objective: The intent of this manuscript was to document the combined injury pattern of a concomitant MPFL rupture and patellar tendon disruption. We also aimed to describe a treatment option for this rarely documented injury pattern.Materials and Methods: Our MPFL reconstruction technique utilized a gracilis allograft and 2 biocomposite anchors for the patella. Our patellar tendon repair utilized Ethibond suture in a Krakow stitch fashion, which was subsequently incorporated into the anchors used for the MPFL reconstruction.Results: Our patient successfully transitioned through a specific postoperative range of motion protocol by increasing knee flexion 30 degrees every 2 weeks, beginning at 0 to 30 degrees at the first postoperative visit. Our patient was able to straight leg raise by 6 weeks, began formal physical therapy at 8 weeks, and resumed all normal activity at 6 months. Conclusion:We demonstrated a novel technique to repair a combined injury of the MPFL and patellar tendon that produced good clinical outcomes through 6 months.

A dedicated high-level computer language has been written for use with a computer-controlled electroanalytical system. The language can be compiled t o produce executable machine code modules, and provides considerable flexibility i n the design of experiments. The compiled modules can be linked t o programs in other high-level languages, allowing very complex strategies to be implemented. The language is sufficiently general t o allow extension t o the control of other types of analytical instrumentation.