Origin and insertion of the medial patellofemoral ligament: a systematic review of anatomy.

PURPOSE: The medial patellofemoral ligament (MPFL) is the major medial soft-tissue stabiliser of the patella, originating from the medial femoral condyle and inserting onto the medial patella. The exact position reported in the literature varies. Understanding the true anatomical origin and insertion of the MPFL is critical to successful reconstruction. The purpose of this systematic review was to determine these locations. METHODS: A systematic search of published (AMED, CINAHL, MEDLINE, EMBASE, PubMed and Cochrane Library) and unpublished literature databases was conducted from their inception to the 3 February 2016. All papers investigating the anatomy of the MPFL were eligible. Methodological quality was assessed using a modified CASP tool. A narrative analysis approach was adopted to synthesise the findings. RESULTS: After screening and review of 2045 papers, a total of 67 studies investigating the relevant anatomy were included. From this, the origin appears to be from an area rather than (as previously reported) a single point on the medial femoral condyle. The weighted average length was 56 mm with an 'hourglass' shape, fanning out at both ligament ends. CONCLUSION: The MPFL is an hourglass-shaped structure running from a triangular space between the adductor tubercle, medial femoral epicondyle and gastrocnemius tubercle and inserts onto the superomedial aspect of the patella. Awareness of anatomy is critical for assessment, anatomical repair and successful surgical patellar stabilisation. LEVEL OF EVIDENCE: Systematic review of anatomical dissections and imaging studies, Level IV

R WAVES INTERRUPTING T WAVES

In the course of some experiments on anesthe-tized dogs and cats concerned with the production experimentally of ventricular flutter and ventricular fibrillation, Fastier and Smirk (1948) noted that R waves sometimes appeared on the descent of the antecedent T waves, shortly before the onset of veit-tricular flutter. The flutter was induced by a sub-stance amarin * which had been found by one of us (F.H.S.) to alter the response of the animals to adrenaline so that a moderate dose of adrenaline, ordinarily well tolerated, would now give rise to ventricular flutter. These observations led me to seek more closely for such phenomena in human electrocardiograms. The present paper concerns 17 patients in whom R waves have been observed on the T waves of ante-cedent complexes. It seems that interruptions of T waves by R waves are not very uncommon, are likely to prove important prognostically, and seem to provide an indication for treatment. Little has been written on this subject either from the experimental or from the clinical standpoint, and such information as is available may be un-familiar to some of the authors who have published records without commenting upon the-phenomenon. The first reference I was able to discover to the occurrence of an R wave on a T wave was in a foot-note by Katz (1928) in the course of his compre-hensive review on the T wave. Katz mentioned here that an example of an R wave on a T wave has been observed by Dr. Ashman, three examples by Drs. reil and Seigel, and three by himself. He mentioned that the only published record was by Wenkebach and Winterberg (1927) and that Wiggers had seen it in dogs. I have been unable to find any record of subsequent reports on the finding of R waves on the T waves with the exception of Scherf * C.H5-CH-NH\ C8H5-CH N `