Michael Younghyeuk Im MD, Presenter: Nothing to Disclose

Donald Rose, Abstract Co-Author: Nothing to Disclose

Jenny Teresa Bencardino MD, Abstract Co-Author: Nothing to Disclose

To determine the association between tunnel widening and cyst formation with graft dysfunction after ACL reconstruction using hamstring autograft based on radiographic and clinical evaluation.

Fifty-seven consecutive patients (M/F=30/27; age=17-54 years, mean 33) who underwent hamstring ACL autograft using a four-strand technique were prospectively collected from April 2006 to March 2009. All patients had baseline radiographs at 1 week following surgery. Forty patients had postoperative radiographic follow-up at 3-6 months and 4/40 patients had follow-up radiographs at 9 to12 months. The following radiographic variables were recorded: 1) tibial and femoral tunnel width, 2) tunnel cyst formation, 3) effusion and 4) anterior tibial translation. Increased tunnel width was assessed in 40 patients wtih radiographic follow-up. Increased tunnel width and tunnel cyst formation were correlated with clinical outcomes of graft dysfunction (ACL laxity or surgical re-interventions).

The femoral tunnel AP width at baseline ranged from 3 to 11 mm (mean=6). At 3-6 month follow- up, the femoral tunnel width measured 3 to 10 mm (mean=6). At 9-12 month follow up, the femoral tunnel width ranged from 4 to 6 mm, (mean=5). None of the subjects demonstrated greater than 1 mm femoral tunnel widening over time. The tibial tunnel AP width at baseline ranged from 4 mm to 15 mm (mean=11). At 3-6 month follow-up, the tibial tunnel width ranged from 5 mm to 19 cm (mean=13). The tibial tunnel width at 9-12 month follow up ranged from 11 to 16 (mean=13). Tibial tunnel widening ranging from 2-8 mm was seen in 21/40 (52.5%). Moderate to large joint effusion was seen in 93% (53/57) of patients at baseline.  Persistent moderate to large effusions at 3-6 months were noted in 32.5% (13/40). Persistent effusion had a positive association with tunnel widening and cyst formation. None of the subjects with tunnel cyst formation and widening demonstrated clinical or radiographic signs of graft laxity nor required re-intervention at 12 months follow-up.  

Tibial tunnel widening and cyst formation are frequently observed on postoperative radiographs following four-strand hamstring autograft ACL reconstruction. They both are associated with persistent postoperative joint effusion.

Tibial tunnel widening and cyst formation are not associated with clinical and radiographic signs of ACL graft dysfunction.

Im, M, Rose, D, Bencardino, J, Hamstring Autograft of the Anterior Cruciate Ligament: Tunnel Widening and Cyst Formation.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8009785.html