RESEARCH REPORT PLATFORM PRESENTATION

A PROSPECTIVE STUDY ON KNEE PROPRIOCEPTION AFTER MENISCAL ALLOGRAFT TRANSPLANTATION. Thijs Y¹, Witvrouw E¹, Evens B¹, Coorevits P¹, Almqvist F², Verdonk R²; ¹Ghent University, Ghent, Belgium. ²Ghent University Hospital, Ghent, Belgium

PURPOSE: The meniscus plays an important role in the proprioceptive ability of the knee joint. The aim of this prospective study was to assess the short term influence of a meniscus replacement on the proprioception of the knee. RELEVANCE: The results of this study suggest that although no significant improvement of pain and functionality of the operated knee occurred at this short term follow-up period, a meniscal allograft transplantation seems to have a significant positive effect on the joint position sense of the previously meniscectomised knee. PARTICIPANTS: 14 patients who had undergone a fresh meniscal allograft transplantation between May 2001 and June 2003 in the Ghent University Hospital were tested preoperatively and six months postoperatively. METHODS: Disability regarding pain, stiffness and functionality of the affected knee during daily activities was measured by the WOMAC-scale. The knee joint position sense was assessed using the Biodex System 3^® Isokinetic Dynamometer. ANALYSIS: Independent-Samples T-tests were used to compare the preoperative proprioception results of the affected knee with those of the unaffected knee. Paired-Samples T-tests were used to test differences between the pre-and postoperative proprioception results within the groups (operated and contra-lateral knee). Changes in differences of the proprioception between the affected and unaffected knee were analysed by means of independent-samples T-tests on the change score of both groups. The change score of a group was defined as the increase or decrease made pre to post by that group. One-sample T-tests were performed to determine significant differences between the obtained proprioception results and the reference angles (30° and 70° knee flexion). The results of the WOMAC-index were analysed by paired-samples T-tests. RESULTS: The results of the WOMAC-scale showed no significant differences concerning pain, stiffness or knee function between the pre- and postoperative condition of the knee. Assessment of the knee joint position sense at a reference point of 70° of knee flexion revealed a significant improvement of the proprioception of the operated knee at six months after surgery compared to the preoperative condition. CONCLUSIONS: The results of this study showed the appearance of a significant deficit of knee joint proprioception after a total meniscectomy. Following a meniscal allograft transplantation, a significant improvement of the knee proprioception was seen at 70° of knee flexion at short term (six months) despite the absence of detectable changes in knee functionality. IMPLICATIONS: The improvement in proprioception following a meniscus transplantation may have a considerable impact on the knee functionality in long term as the subjective stability of the joint becomes more and more important when patients are exposing their knee to higher demands in sports- or daily activities. Therefore the results of this study are the first to suggest that the long term functional results after a meniscal transplantation may also be the consequence of an improved proprioception. KEYWORDS: meniscus; meniscectomy; meniscal transplantation; proprioception; knee joint position sense. FUNDING ACKNOWLEDGEMENTS: This work was unfunded.

ETHICS COMMITTEE: Ethics Committee Ghent University Hospital