A quadriceps tendon graft may be used to reconstruct the anterior cruciate ligament (Crall & Gilmer 2015; Geib et al. 2009; Lee et al. 2016; Lee et al. 2007; Marshall et al. 1979; Slone et al. 2015), the posterior cruciate ligament (Chen et al.; Chen et al. 2004; Wu et al. 2007), the medial patellofemoral ligament (Lenschow et al. 2015; Steiner et al. 2006), the lateral collateral ligament (Chen et al. 2001) and the Achilles tendon (Arriaza et al. 2016). This autograft shares biological and mechanical properties with other grafts such as the patellar ligament or hamstrings, sometimes with superiority (Han et al. 2008). Harvesting the quadriceps tendon (with or without patellar bone) might have an impact on the function of the extensor apparatus of the knee joint as a whole. The removal of a tendon graft probably alters the delicate interplay between different layers of the extensor apparatus. Chen et al. reported that 9 % of subjects exhibited donor site pain after quadriceps graft harvesting, and the risk of occult partial rupture of the remaining quadriceps tendon may exist. Late quadriceps tendon rupture at the donor site following harvesting of a quadriceps tendon graft has been reported (Pandey et al. 2015). Loss of quadriceps muscle strength of 20 % after harvesting the quadriceps tendon graft for anterior cruciate ligament reconstruction and prolonged weakness of knee extension strength, predominantly in women, have also been reported (Chen et al. 2006; Yasuda et al.). However, others report low donor-site morbidity when using a quadriceps tendon graft compared to a bone tendon bone graft of the patellar ligament (Gorschewsky et al. 2007; Han et al. 2008; Lund et al. 2014). The harvesting technique may also impact the outcome. For example, if the quadriceps tendon is harvested at the fusing points (Fig. 3b) it is questionable that such a graft is suitable as a firm graft. A harvest of the quadriceps tendon medial to the fusing points of the intermediate layers violates the insertion of the vastus medialis with potential consequences on the terminal phase of extension and patellar stability (Lieb & Perry 1971; Pocock 1963; Toumi et al. 2007). On the other hand a lateral harvest of the quadriceps tendon compromises the insertion of the vastus lateralis and the tensor vastus intermedius. Based on the present anatomic findings it can be assumed that a harvest of a tendon graft lateral of the fusing points of the two-layered intermediate layer would be of better quality than a medial graft removal (Fig. 3a). Questions arise whether a partial- or full-thickness graft should be harvested and how closure of tendon defects should be performed. Latter questions also arise with regards to parapatellar approaches to the knee joint.