Extrusion of the medial meniscus is a potential predisposing factor for post-arthroscopy osteonecrosis of the knee

Table 4 Intra- and post-operative data for the 10 matched control knees. Summary of continuous variables is shown as “mean (standard deviation)”

Patient No	Age Sex	Type of MM tear	Surgery Done	Resected width of MM	Postoperative period until taking the MRI^a
1.	50’s, F	HT at Posterior	PMM, PLM	Half	11 wks
2.	60’s, F	HT at Posterior	PMM	Half	6 wks
3.	60’s, F	HT at Posterior	PMM	Half	17 wks
4.	60’s, F	RT with HT at Posterior	PMM, PLM	Half	4 wks
5.	60’s, F	HT at Posterior	PMM, PLM	Half	3 wks
6.	70’s, F	HT at Posterior	PMM	Half	13 wks
7.	70’s, F	RT with HT at Posterior	PMM	Half	35 wks
8.	70’s, F	RT with HT at Posterior	PMM, PLM	Half	50 wks
9.	80’s, M	RT at Posterior	PMM	Half	12 wks
10.	60’s, M	RT with HT at Posterior	PMM	Half	13 wks
Summary		HT: 5	PMM: 10	Subtotal: 0	16.6 wks
		RT: 5	PLM: 4	Half: 10	(14.3)

F Female, M Male, MM Medial meniscus, RT Radial tear, PH Posterior horn, HT Horizontal tear, PRT Posterior root tear, PMM Partial medial meniscectomy, PLM Partial lateral meniscectomy, LMR Lateral meniscus repair. ^a The period between the meniscectomy and the time of taking the postoperative MRI

ISSN: 1471-2474