Tendon Graft Fixation Sites at the Coracoid Process for Reconstruction of the Coracoclavicular Ligaments: A Kinematic Evaluation of Three Different Surgical Techniques Kaywan Izadpanah, M.D., Martin Jaeger, M.D., Dirk Maier, M.D., Peter Ogon, M.D., Matthias Honal, Ph.D., Marco Vicari, Ph.D., Jürgen Hennig, Ph.D., Norbert P. Südkamp, M.D., and Matthias Weigel, Ph.D. Purpose: The virtual graft length kinematics of 3 operative techniques were investigated and compared with kinematics of the native coracoclavicular ligaments. Methods: Thirteen healthy volunteers underwent magnetic resonance imaging (MRI) of the shoulder in 30  increments of abduction (0  to 120  ). A 3-dimensional model of the coracoid process (CP) and the clavicle (CL) was created. Footprints of the conoid and the trapezoid ligament were identified. At the CP the potential fixation sites of 3 techniques for reconstruction of the coracoclavicular ligaments (CCLs) were marked. The techniques investigated were (1) horizontal transcoracoid drilling (TH), (2) transclavicularetranscoracoid drilling (TT), and (3) tendon graft passage underneath (PU) the coracoid process. Distances between the clavicular and coracoidal footprints of the coracoclavicular ligaments and to the virtual footprints on the coracoid process were determined for each abduction increment. Results: All methods investigated resulted in a significantly longer virtual trapezoidal graft (P ¼ .001). In PU, in addition, the virtual conoidal graft was significantly longer. TT resulted in a virtual conoidal graft and conoid ligament of equal length. TH showed identical length and distance regulation of the virtual conoidal graft and the conoid ligament, but significant shortening of the virtual trapezoidal graft during abduction. PU showed isometry of the virtual trapezoidal and conoidal grafts. Conclusions: None of the described procedures for graft fixation restores the kinematics of the native coracoclavicular ligaments. Graft fixation techniques should be chosen with respect to the preoperative type of instability. Persisting isolated vertical instability might benefit from fixation of the conoidal grafts at the native clavicular footprint. For horizontal clavicular instabilities, techniques more preserving of trapezoid ligament kinematics might be favorable. Clinical Relevance: The data suggest that the technique of fixation in conoid and trapezoid ligament reconstruction should depend on the underlying type of instability. R econstruction of the conoid and trapezoid liga- ments using tendon grafts represents a standard technique for the treatment of chronic acromiocla- vicular joint (ACJ) instability. 1-5 At the clavicle, tendon grafts are regularly fixed at the footprints of the coracoclavicular ligaments. However, graft fixation at the coracoid process is technically demanding, and there is a potential risk of coracoid fracturing. 6 Therefore various alternative open and arthroscopic procedures have been developed. 1,3,5 Most of the latter do not or just partially fixate the grafts at the genuine coracoidal foot- prints of the conoid and trapezoid ligaments. However, they claim to perform a functional anatomic recon- struction. We recently reported that the coracoclavicular ligaments have a dedicated distance kinematics during shoulder abduction. They therefore function as dynamic stabilizers of the lateral clavicle during shoulder motion in vivo. 7 So far little is known about the influence graft placement during coracoclavicular ligament recon- struction has on the ability to stabilize the lateral clavicle during shoulder motion. Brophy and Pearle 8 determined the effect of tunnel positioning on knee joint stability in anterior cruciate ligament reconstruction by investi- gating the length changes of virtual tendon grafts during knee flexion. From the Department of Orthopaedic and Trauma Surgery (K.I., M.J., D.M., P.O., N.P.S.) and Department of Radiology and Medical Physics (M.H., J.H., M.W.), University Hospital Freiburg, Freiburg, Germany, and Esaote S.p.A. (M.V.), Genoa, Italy. The authors report the following potential conflict of interest or source of funding in relation to this article: M.V. is an employee of and J.H. is a consultant for Esaote S.p.A., Genoa, Italy. Received March 14, 2012; accepted August 28, 2012. Address correspondence to Kaywan Izadpanah, M.D., Department of Orthopaedic and Trauma Surgery, University Hospital Freiburg, Hugstetter 55, 79106 Freiburg im Breisgau, Germany. E-mail: izadpanah@me.com Ó 2013 by the Arthroscopy Association of North America 0749-8063/12174/$36.00 http://dx.doi.org/10.1016/j.arthro.2012.08.026 Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 29, No 2 (February), 2013: pp 317-324 317