Comparison of four chondral repair techniques in the hip joint: a biomechanical study using a physiological human...

The objective of this study was to assess the biomechanical stability of three types of chondral flap repair techniques as well as a hydrogel scaffold implantation on the acetabular articular surface using a physiological human cadaveric model.

Chondral flaps were created in the antero-superior zone of the acetabulum in a series of human cadaveric hip joints. The chondral flap was repaired by fibrin glue, cyanoacrylate, suture technique and an agarose hydrogel scaffold sealed with fibrin glue using six hips in each case. After each repair, the specimens were mounted in a validated jig and tested for 1500 gait cycles. In order to determine the stability of the repair, specimens were evaluated arthroscopically at specific intervals.

The fibrin glue and cyanoacrylate techniques were technically the easiest to perform arthroscopically, all flaps repaired with fibrin were detached at 50 cycles while those repaired with cyanoacrylate lasted for an average of 635 cycles. On the other hand, both the suture repair and scaffold implantation techniques were more technically challenging but were both stable till the endpoint of 1500 cycles.

Fibrin glue on its own does not provide sufficient fixation to repair chondral flaps on the acetabular surface. Cyanoacrylate repairs universally failed midway through the testing protocol employed here, raising doubts as to the effectiveness of that technique. The suture and hydrogel scaffold technique were the most reliable for chondral repair at any given cycle. The results of this biomechanical study demonstrate the relative effectiveness of chondral repair and fixation techniques.