Background: During the early postoperative period, the fixation of a hamstring graft to the bone tunnel is the primary factor in limiting rehabilitation.
Hypothesis: The initial fixation strength of a double cross pin fixation technique is comparable with the biodegradable interference screw fixation technique.
Study Design: Experimental laboratory study.
Methods: The authors examined the initial fixation strength of two 3.3-mm bioabsorbable pins compared to interference screws for hamstring grafts in bovine knees.
Results: Analysis of yield load, maximum load, and stiffness in the single-cycle loading test showed no statistically significant differences for cross pin and interference fixation (P< .05). For cross pins and interference screws, the mean displacement under 1000 cycles to 250 N was 5.07 (± 1.9) mm and 4.81 (± 2.5) mm, stiffness 252 (± 78) N/mm and 289 (± 148) N/mm. Only grafts fixed with cross pins survived 1000 cycles to 450 N.
Conclusion: The initial fixation strength of the double cross pin technique is comparable to that of interference screw fixation with a stiffness comparable to that of the native ACL.
Clinical Relevance: Hamstring graft fixation using two cross pins provides an alternative to bioabsorbable interference screw fixation.
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