Viability assessment of the chondral flap in patients with cam-type femoroacetabular impingement: a preliminary report.
BACKGROUND
Delaminated acetabular cartilage is a common finding in patients undergoing surgical dislocation or hip arthroscopy in the treatment of cam-type femoroacetabular impingement. Current treatment involves resection of the free cartilage flap with or without acetabular rim trimming. The viability of the delaminated cartilage flap is not known. We sought to examine if the acetabular cartilage still has viable cartilage cells and, if so, what type of cartilage is present.


METHODS
We examined the delaminated cartilage flaps from patients undergoing surgical dislocation and osteochondroplasty for symptomatic cam-type impingement. We performed hematoxylin and eosin staining and histological analysis using light microscopy to determine cartilage viability and cartilage type.


RESULTS
We examined 12 delaminated cartilage flaps from 11 patients (10 men, 1 woman, average age 30.1 yr). Ninety percent chondrocyte viability was confirmed in 11 of 12 flaps. Six of 12 flaps were composed predominantly of hyaline cartilage, 4 were a mixed population of fibrocartilage and hyaline cartilage and 2 were predominantly fibrocartilage.


CONCLUSIONS
Our findings suggest that the delaminated cartilage flap in patients with femoroacetabular impingement may retain a large amount of viable chondrocytes. Development of surgical techniques focusing on refixation of this flap as an alternative to excision and microfracture should be considered.
From the Ottawa Hospital, Ottawa, Ont.
Brad
B
Meulenkamp
From the Ottawa Hospital, Ottawa, Ont.
Denis
D
Gravel
From the Ottawa Hospital, Ottawa, Ont.
Paul E
PE
Beaulé
D000077:Acetabulum / Q000601:surgery; D000293:Adolescent; D000328:Adult; D002358:Cartilage, Articular / Q000166:cytology / Q000473:pathology / Q000601:surgery*; D002470:Cell Survival; D019902:Chondrocytes / Q000473:pathology / Q000502:physiology*; D005260:Female; D057925:Femoracetabular Impingement / Q000473:pathology / Q000601:surgery*; D051445:Fibrocartilage / Q000473:pathology / Q000502:physiology; D058752:Free Tissue Flaps; D006801:Humans; D051457:Hyaline Cartilage / Q000473:pathology / Q000502:physiology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult