LONG-TERM RESULTS OF ABRASION ARTHROPLASTY OF THE MEDIAL FEMORAL CONDYLE OF THE KNEE FOR

FULL-THICKNESS CHONDRAL DEFECTS

Sansone V., de Girolamo L1, Melato M., Pascale V.

Department of Orthopaedics and Traumatology, Università degli Studi di Milano, Galeazzi Orthopaedic Institute, Milan, Italy

1Orthopaedic Biotechnologies Lab, Galeazzi Orthopaedic Institute, Milan, Italy

BACKGROUND

Abrasion arthroplasty is one of the most common surgical techniques used to repair chondral lesions. It is an arthroscopic procedure intended to stimulate bleeding in the sub-chondral bone. The aim is to induce the formation of fibrocartilage that will fill the chondral defect. Although it is a simple and low cost treatment that has been used extensively, there are surprisingly few data regarding long-term outcomes.

AIM OF THE STUDY

To evaluate the outcome of abrasion arthroplasty of the medial femoral condyle, performed by a single surgeon at 10 years follow-up. Failure was defined as the requirement for re-operation of the same knee.

Lesion KSS ≥ 70 KSS < 70

Present 24 19

Assent 11 11

RESULTS

65 patients (86.7%) were available for follow-up (1 patient died and 9 were lost at follow-up). Mean age at the time of operation was 53.7 years ± 16.9 years (Females = 58 ± 14 years, Males⌀⌀ = 48.8 ± 18.6 years) with a mean follow-up of 10 years (range 5 -15 ± 2

years).

PATIENTS & METHODS

From 3/1990 to 12/2000, 75 consecutive patients suffering from a full thickness chondral defect of the medial femoral condyle underwent abrasion arthroplasty performed by a single surgeon (V.S.). Inclusion criteria were having undergone abrasion arthroplasty with a minimum 5-yr follow-up. Patients with ligament injuries, multiple compartment involvement, varus angulation > 10° and inflammatory arthritis were excluded from the study.Pre-operative weight-bearing radiographs of the knee were obtained in all cases. At final follow-up patients completed the KSS (Knee Society Score) questionnaire to measure their current knee symptoms and the need for further surgery. Patients were considered to have a successful result if they obtained good or excellent grading in KSS and had not undergone repeat surgery (survivorship).

Dimension KSS ≥ 70 KSS < 70

< 2cm 21 10

≥ 2cm 14 20

Age KSS ≥ 70 KSS < 70

< 50y 21 10

≥ 50y 14 20

Sex KSS ≥ 70 KSS < 70

M 15 16

F 20 14

REFERENCES

DISCUSSION & CONCLUSIONS

Abrasion arthroplasty aims to fill full-thickness chondral defects, avoiding further degeneration of the articular cartilage. It is intended to be a temporary measure to delay the onset of arthritis, which is the natural history of such lesions. • In our series, the dimension of the lesion seemed to be crucial in determining the quality of the result. The procedure showed to be effective in controlling the progression of degeneration of small lesions (Fig. C, G p<0.05).

• Only patients of 50 years or older underwent a second operation. However, among non-reoperated patients no significant clinical differences were observed between the two age groups.

• Patients with both medial and lateral meniscal lesions had a worse survivor rate in comparison to the other groups.

• Abrasion arthroplasty is not indicated for patients with chondral lesions of the medial femoral condyle larger than 2 cm in diameter (3.14 cm²).

p > 0.05

p > 0.05

p > 0.05

p < 0.05

• . Bert, J.M. and K. Maschka, The arthroscopic treatment of unicompartmental gonarthrosis: a five-year follow-up study of abrasion arthroplasty plus arthroscopic debridement and arthroscopic debridement alone. Arthroscopy, 1989. 5(1): p. 25-32.

• Friedman, M.J., et al., Preliminary results with abrasion arthroplasty in the osteoarthritic knee. Clin Orthop Relat Res, 1984(182): p. 200-5..

• Insall, J., The Pridie debridement operation for osteoarthritis of the knee. Clin Orthop Relat Res, 1974(101): p. 61-7.

• Johnson, L.L., Arthroscopic abrasion arthroplasty historical and pathologic perspective: present status. Arthroscopy, 1986. 2(1): p. 54-69.

• Johnson, L.L., Arthroscopic abrasion arthroplasty: a review. Clin Orthop Relat Res, 2001(391 Suppl): p. S306-17.

• Matsunaga, D., et al., Repair of articular cartilage and clinical outcome after osteotomy with microfracture or abrasion arthroplasty for medial gonarthrosis. Knee, 2007. 14(6): p. 465-71.

KSS

SURVIVORSHIP

A B C D

E F G H

Total

Male

Female

Total

<50 y

≥50 y

Total

⌀<2 cm

⌀≥2 cm

Total

Absent

Med. Men.

Med. Men. + Lat. Men. n = 10 events = 4

Lat. Men. n = 3 events = 0

n = 65 events =

8

n = 14 events =

0

n = 46 events =

8

n = 65 events =

8

n = 31 events =

2

n = 34 events =

6

n = 65 events = 8

n = 22 events = 3

n = 30 events = 1

n = 65 events =

8

n = 31 events =

5

n = 34 events =

3