Purpose of study The aim of this study was to evaluate clinical and radiological sequelae following removal of part of the patellar tendon for A.C.L. reconstruction. Materials and methods A consecutive and homogenous series of 100 patients operated for chronic anterior instability (66 men, 34 women; age 16 to 55 years, average : 28.5 years) was studied, The procedure involved a free patellar tendon graft harvested from the mid third of the tendon and including its bony attachments, and in particular a long strip from the patella and a strip 10 centimeters long from the rectus femoris tendon for extra-articular reconstruction. Tendon graft sites were closed, Patellae and tibial tunnels were filled with bone debris from the drilling, and the pre-patellar fascia was closed. The mean followup period was 35 months. Pain and radiological alterations (with pre-operative X-rays as reference) were studied, particularly for: calcifications patellar height changes using the Insall, Blackburne and Caton methods increase in patella tip length femoro-patellar joint alteration. Results Calcification were found in: quadriceps tendon:24 per cent of cases (always painless) Pre-patellar:16 per cent of cases (usually less than 5 mm) Superior patellar tendon:47 per cent of Gases (only 2 cases being painful, no unaffected tendons were painful) Inferior patellar tendon:7 per cent of cases (1 in the mid) Tibia tunnel:26 per cent of cases. No cases required surgical removal. Patellar tip length did not increased significantly. Patellar tendon length decreased by 1.37 mm. Patellar height measured by the Insall, Blackburne and Caton methods was not significantly affected. The femoro-patellar joint was normal in 95 per cent of cases, There were five cases of remodelling, one being painful. Conclusion Graft harvested from the extension system for A.C.L. reconstruction frequently resulted in radiological sequelae but were usually asymptomatic, In most cases these calcifications concerned the superior patellar tendon, quadricipital tendon and pre-patellar zone. Patella height was not affected.