Conversion of patellofemoral arthroplasty to total knee arthroplasty

Figures & data

Table 1. Demographic and radiographic data for 14 knees with a patellofemoral arthroplasty prior to conversion to total knee arthroplasty (index group) and 14 knees with primary total knee arthroplasties (control group)

	Index	Control	p-value
Sex (female : male)	10 : 3	10 : 3
No. of knees	14	14
Age at time of total knee arthroplasty, years (range)	67 (50–77)	68 (51–76)	0.7
Follow-up, years (range)	5.7 (2.0–13)	5.2 (2.1–13)	0.1
Body mass index (range)	29 (22–35)	29 (23–34)	0.4
Kellgren grade			0.3
1	0	0
2	6	8
3	6	2
4	2	4
Ahlbäck grade			0.6
1	11	12
2	2	0
3	1	2
4	0	0

Figure 1. Patellofemoral prosthesis in situ.

Figure 2. After removal of femoral and patellar components.

Figure 3. After preparation of distal femur and proximal tibia using the standard cutting blocks.

Table 2. Clinical outcome after total knee arthroplasty. Values are mean (SD)

	Index	Control	p-value
KSS (max. 100)	82 (19)	86 (10)	0.6
KSS function (max. 100)	76 (31)	88 (10)	0.5
WOMAC (max. 96)	33 (23)	21 (16)	0.1
Preoperative flexion (degrees)	108 (14)	110 (12)	0.7
Postoperative flexion (degrees)	117 (13)	116 (11)	0.9