Knee Surgery, Sports Traumatology, Arthroscopy

, Volume 16, Issue 12, pp 1114–1120 | Cite as

The fate of patellar tendon and infrapatellar fat pad after arthroscopy via central portal

  • Ahmet Bayar
  • Egemen Turhan
  • Tülay Özer
  • Selçuk Keser
  • Ahmet Ege
  • Zuhal Erdem


Central patellar (CP) portal is an accessory portal in arthroscopic knee surgery, which generally is considered to be safe. In this cross sectional study, we aimed to delineate the clinical and radiological outcome of patellar tendon (PT) and Hoffa’s fat pad after the use of this approach. From our hospital records, patients who underwent arthroscopy via CP portal were identified and were invited for the study. There were16 men and 4 women with a mean age of 32 years. Mean follow-up time was 28 months. Meniscectomy had been performed for irreparable bucket-handle type medial meniscal tears in all patients. At the latest follow-up, no patients had anterior knee pain and physical examination was normal. Mean PT thickness of operated knees measured with Ultrasonography was 5.63 ± 1.56, while it was 3.76 ± 0.46 mm in contralateral knees and the difference was significant. Contour irregularity of PT and focal hypoechoic areas were found in 17 patients, two of which also had hyperechogenic calcification focuses. Abnormal signal intensity of PT was also found in 17 patients with Magnetic Resonance Imaging (MRI). Eleven of these had decreased signal intensity within the tendon which was interpreted as fibrosis. In six patients, increased signal intensity, radiologically similar to chronic tendinitis, was detected. Four patients had decreased signal intensity in the Hoffa’s fat pad. Local fibrous tissues in patellar tendon might cause weakness in the tendon. This study showed that although CP portal did not cause any clinical problems in a low demand group of patients, it leads to a significant radiological sequela in the tendon, biomechanical significance of which needs to be clarified.


Central portal Arthroscopy Patellar tendon Chronic tendinitis Fibrosis 


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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Ahmet Bayar
    • 1
  • Egemen Turhan
    • 1
  • Tülay Özer
    • 2
  • Selçuk Keser
    • 1
  • Ahmet Ege
    • 1
  • Zuhal Erdem
    • 3
  1. 1.Department of Orthopaedics and Traumatology, Faculty of MedicineZonguldak Karaelmas UniversityKozluTurkey
  2. 2.İzmit Gözlem Radiology CenterİzmitTurkey
  3. 3.Department of Radiology, Faculty of MedicineZonguldak Karaelmas UniversityKozluTurkey

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