First, we feel honored receiving interest by such an authority in the field of orthopedic knee surgery as Dr. Merchant. However, we disagree with his statement that the turn-up sign to 90° was quickly discarded or never adopted after being described in 1986.1Henry J.H. Goletz T.H. Williamson B. Lateral retinacular release in patellofemoral subluxation. Indications, results, and comparison to open patellofemoral reconstruction.Am J Sports Med. 1986; 14: 121-129Crossref PubMed Scopus (70) Google Scholar No evidence or recommendation was available in the listed international publications when we started our prospective study in 2008. In contrast, the current “state-of-the-art” technique in 2008 as described in Master Techniques in Orthopaedic Surgery: Reconstructive Knee Surgery pointed out that “a turn-up sign of 90° should be performed to assure adequate release” (Figure 1.9, page 9).2Gasser S. Cucchetti B. Arthroscopic lateral release of the patella with radiofrequency ablation.in: Jackson D. Master techniques in orthopaedic surgery: Reconstructive knee surgery. Ed 3. Lippincott, Williams & Wilkins, Philadelphia2008: 1-11Google Scholar The authors of this book and article are renowned chairmen and experts in the field of orthopaedic surgery in the United States, but obviously have not been aware of the potential risk of the 90° turn-up sign during release. In contrast, Dr. Merchant mentioned the book chapter published by Ewing3Ewing J.W. Arthroscopic patellar shaving and lateral retinacular release.in: McGinty J.B. Operative arthroscopy. Raven, New York1991Google Scholar in 1991 that recommended a turn-up of 60°. Unfortunately, this book chapter is not available in the listed scientific material for international specialists. In addition, we could not find Dr. Merchant's personal publication in the available literature that gives the recommendation to limit the turn-up sign to less than 90°. We immediately published our results and our recommendation to reduce the turn-up sign to 70° (included in the “Discussion” section of our article).4Pagenstert G. Wolf N. Bachmann M. et al.Open lateral patellar retinacular lengthening versus open retinacular release in lateral patellar hypercompression syndrome: A prospective double-blinded comparative study on complications and outcome.Arthroscopy. 2012; 28: 788-797Abstract Full Text Full Text PDF PubMed Scopus (66) Google Scholar We absolutely agree that the publication of Dr. Merchant's letter together with our study will help to correct this deficiency of knowledge in US and international orthopaedic societies. Finally, we really appreciate this kind of discussion based on letters to the editor, because it points out minor details that turn out to be most critical in obtaining good or bad results. However, we will not repeat the study with a turn-up sign of 60° or 70° because we believe, in our Level II evidence, that lateral retinacular lengthening will give better results than simply cutting the lateral retinaculum because of preserved muscle, iliotibial band, and retinacular fiber connection despite the extent of the turn-up sign used. We hope other readers will take the opportunity to share in our discussion and follow our consensus recommendation for a limited turn-up sign during lateral retinacular release. Is It Lateral Retinacular Lengthening Versus Lateral Retinacular Release or Over-Release?ArthroscopyVol. 29Issue 3PreviewAs the first author to publish about the lateral release, in 1974,1 I feel an obligation to comment on the article “Open Lateral Patellar Retinacular Lengthening Versus Open Retinacular Release in Lateral Patellar Hypercompression Syndrome: A Prospective Double-Blinded Comparative Study on Complications and Outcome” by Pagenstert et al.2 in the June 2012 issue of Arthroscopy. The abstract describes a well-designed prospective study with the results clearly favoring lengthening compared with release. Full-Text PDF