Repair of the medial patellofemoral ligament with suture tape augmentation leads to similar primary contact pressures and joint kinematics like reconstruction with a tendon graft: a biomechanical comparison
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To compare suture tape-augmented MPFL repair with allograft MPFL reconstruction using patellofemoral contact pressure and joint kinematics to assess the risk of patellofemoral over-constrainment at point zero.
A total of ten fresh frozen cadaveric knee specimens were tested in four different conditions of the MPFL: (1) native, (2) cut, (3) reconstructed with tendon graft, and (4) augmented with suture tape. The patellofemoral mean pressure (MP), peak pressure (PP) and contact area (CA) were measured independently for the medial and lateral compartments using pressure-sensitive films. Patellar tilt (PT) and shift (PS) were measured using an optical 3D motion tracking system. Measurements were recorded at 0°, 10°, 20°, 30°, 60° and 90° of flexion. Both the tendon graft and the internal brace were preloaded with 2 N, 5 N, and 10 N.
There was no significant differences found between surgical methods for medial MP, medial PP, medial CA, lateral MP and PS at any preload or flexion angle. Significant differences were seen for lateral PP at 20° knee flexion and 10 N preload (suture tape vs. reconstruction: 1045.9 ± 168.7 kPa vs. 1003.0 ± 151.9 kPa; p = 0.016), for lateral CA at 10° knee flexion and 10 N preload (101.4 ± 39.5 mm2 vs. 108.7 ± 36.6 mm2; p = 0.040), for PT at 10° knee flexion and 2 N preload (− 1.9 ± 2.5° vs. − 2.5 ± 2.3°; p = 0.033) and for PT at 0° knee flexion and 10 N preload (− 0.8 ± 2.5° vs. − 1.8 ± 3.1°; p = 0.040). A preload of 2 N on the suture tape was the closest in restoring the native joint kinematics.
Suture tape augmentation of the MPFL resulted in similar primary contact pressures and joint kinematics in comparison with MPFL reconstruction using a tendon graft. A pretension of 2 N was found to restore the knee joint closest to normal patellofemoral kinematics.
KeywordsPatellofemoral instability Medial patellofemoral ligament Internal ligament bracing Ligament reconstruction Contact pressure Joint kinematics
The University of Connecticut Health Center/UConn Musculoskeletal Institute has received direct funding and material support from Arthrex (Naples, Fl, USA). The company had no influence on study design, data collection or interpretation of the results or the final manuscript.
Compliance with ethical standards
Conlict of interest
K. Beitzel is consultant for Arthrex. A.B. Imhoff is consultant for Arthrosurface and medi and receives royalties from Arthrex and Arthrosurface. All other authors declare, that they have no conflicts of interest.
All study specimens were obtained from Science Care (Phoenix, AZ, USA). The study was reported via Human Research Determination Form to the institutional review board (IRB) of the University of Connecticut, Farmington, CT, USA (IRB JM-18-2) and was documented, that no IRB approval was required.
- 23.Schneider DK, Grawe B, Magnussen RA, Ceasar A, Parikh SN, Wall EJ et al (2016) Outcomes after isolated medial patellofemoral ligament reconstruction for the treatment of recurrent lateral patellar dislocations: a systematic review and meta-analysis. Am J Sports Med. 44:2993–3005 (Epub 2016 Feb 2912) CrossRefGoogle Scholar
- 31.Wilharm A, Hurschler C, Dermitas T, Bohnsack M (2013) Use of Tekscan K-scan sensors for retropatellar pressure measurement avoiding errors during implantation and the effects of shear forces on the measurement precision. Biomed Res Int 2013:829171. https://doi.org/10.1155/2013/829171 CrossRefGoogle Scholar
- 32.Yang JS, Fulkerson JP, Obopilwe E, Voss A, Divenere J, Mazzocca AD et al (2017) Patellofemoral contact pressures after patellar distalization: a biomechanical study. Arthroscopy 33:2038–2044Google Scholar