Table 1.

Criteria used to determine the advanced Ligament Maturity Index (LMI). The five regions from each ligament were separately scored according to the cell, collagen and vessel criteria. The cell, collagen and vessel sub-scores for each ligament were then determined by averaging the scores for each of the five regions using the sub-scores respective criteria. The resulting cell, collagen and vessel sub-scores for each ligament were then summed to determine the total LMI score representing the cumulative indications of healing.

Cell Sub-Score (total = 8 pts)		Collagen Sub-Score (total = 12 pts)		Vessel Sub-Score (total = 6 pts)
Criteria	pts	Criteria	pts	Criteria	pts
Presence of inflammatory cells		Width of bundles		Density of blood vessels
Necrosis	0	No bundles	0	None present	−1
Polymorphonuclear cells	1	Width less than 50 μm	2	more than 200% present	0
No inflammatory cells	2	Width greater than 50 μm	4	150%-200% present	1
				Less than 150% present	2
Nuclear aspect ratio (NAR) of fibroblasts		Bundle orientation with long axis of ligament		Vessel orientation with long axis of ligament
No cells	−1	No bundles	−2	No vessels oriented	−2
Average NAR less than 2 (round)	0	less than 50% oriented	0	Less than 30% oriented	−1
Average NAR 2-4	1	50%-75% oriented	2	less than 50% oriented	0
Average NAR greater than 4 (elongated)	2	75%-100% oriented	4	50%-75% oriented	1
				75%-100% oriented	2
Nucleus of fibroblast aligned with fascicles and long axis of ligament		Collagen Crimp		Vessel maturity
No cells	−2	No crimp	−2	No vessels seen	0
Less than 30% of cells oriented	−1	less than 25% crimp	0	Capillaries only present	1
30%-50% oriented	0	25%-75% crimp	2	Arterioles present	2
50%-75% oriented	1	Crimp with normal length present	4
75%-100% oriented	2
Number of fibroblasts
None	−1
Greater than 2× normal	0
Between 1.5× and 2× normal	1
Less than 1.5× normal	2