Abstract
Statement of Purpose We describe the donor site morbidity of hyaline cartilage biopsy from the trochlea of the knee when used for ACI in the ankle joint.
Methods We studied 12 patients who received a two stage ACI procedure on the talus, performed by three consultant surgeons. The first stage involved knee arthroscopy and harvest of cartilage for culture and stage two the transplantation of a chondrocyte culture to the ankle joint.
During the first stage knee arthroscopy using a superolateral approach, the cartilage specimens were taken from a minor load bearing area of either the central or superolateral trochlea using a 5mm gouge.
Clinical outcomes were assessed using a patient satisfaction score and the Lysholm knee score, taken both pre- and post- operatively at 3 months and annually thereafter.
Results The mean age of the patient group was 42. The patient satisfaction questionnaires showed 11 patients to be ‘pleased’ or ‘extremely pleased’ with their ACI procedure which was sustained in the patients with up to four years follow up.
The mean Lysholm score preoperatively was 98/100. Postoperatively eight patients had a reduced score (mean reduction 14) at twelve months follow up. In those patients with new knee symptoms at one year, analysis of the Lysholm score components showed the Locking and Limp categories to be the most frequent cause of a reduced score. Two patients had repeat knee arthroscopy at 18 months and 2 years postoperatively for symptoms of catching, anterior knee pain and swelling.
Discussion The Lysholm knee score has components which may be affected by ipsilateral joint problems, which contribute to 20% of the overall score. However those patients with an abnormal Lysholm knee score postoperatively have gained an improved Mazur ankle score since their ACI.
The procedure of cartilage harvest from the trochlea of the knee has an associated donor site morbidity which is present at one year. Ninety two percent of patients were pleased or extremely pleased with their ACI procedure, despite the requirement of surgery on their knee and it would seem that the amount of early knee morbidity these patients experience is outweighed by the improvement in symptoms in the treated joint.
Ideally to optimise cartilage repair less morbid techniques to obtain cartilage need to be identified or alternatively mesenchymal stem cells could be used as an alternative source, which has already had limited success in the knee and might also be applied to other joints.
Correspondence should be addressed to Roger Smith, Honorary Secretary, BASK c/o Royal College of Surgeons, 35 – 43 Lincoln’s Inn Fields, London WC2A 3PN
