The relationship between the saphenopopliteal junction and the common peroneal nerve: a cada-veric study

Objectives: The variable anatomy of the short saphenous vein (SSV) and the potential failure to identify the saphenopopliteal junction (SPJ) contribute to an increased risk of damage to the common peroneal nerve (CPN) during surgical exploration. The aim of the present study was to determine the variation of the SPJ, its relationship to the CPN, and the relationship of both SPJ and CPN to defined anatomical landmarks. Methods: Measurements of the distance between the SPJ and CPN, and the defined anatomical landmarks (fibula head, lateral joint space, lateral femoral epicondyle), were undertaken on 30 cadaveric limbs following careful dissection of the popliteal fossa. Results: The level of SPJ termination was classified as low (below), normal (within 100 mm above) and high (more than 100 mm above), the lateral femoral epicondyle. Of the 30 limbs dissected, 70% of SPJs were normal, 23% low and 7% high. Direct measurement from the SPJ to anatomical landmarks showed a higher interquartile range (IQR) in low compared with normal terminations; however, the vertical distance from the SPJ to the fibula head showed an increase in IQR from low to normal terminations (7.1-14.2). The mean distances between the SPJ and CPN in low and normal terminations were 23.3 and 16.7 mm, respectively. Comparison of the IQR showed values very similar to low terminations having a slightly higher IQR compared with normal terminations (7.15-6.0). Conclusion: Significant anatomic variation was observed in the termination of the SSV, with 67% located within 66 mm above the lateral femoral epicondyle. The risk of damaging the CPN during saphenopopliteal ligation may be higher for SPJs located above the lateral femoral epicondyle because of the proximity of the two structures and variability of SPJ.