Dog-ear and bird-beak deformities are common after transosseous-equivalent repair of a rotator cuff tear, according to a new study, however their remodeling potential hasn’t been investigated until now. Transosseous-equivalent repair uses the suture bridge technique.
The study, “Does the Dog-Ear or Bird-Beak Deformity Remodel After Rotator Cuff Repair?” was published online May 5, 2020 in The American Journal of Sports Medicine.
For the study, the researchers studied 99 consecutive shoulders between November 2011 and February 2012 to evaluate remodeling and re-tear rates. All the patients underwent arthroscopic rotator cuff repair via the suture bridge technique with or without additional sutures.
The patients were categorized in two groups: no deformity (n=46) and deformity (n=53). Deformity was defined as marginal detachment and protrusion of the rotator cuff.
Changes in tendon height was evaluated on MRI scan at 1 week and 6 months postoperatively. Tendon height was measured from the highest point of the most protruding portion of the cuff to the cortex. The researchers also collected American Shoulder and Elbow Surgeons (ASES) scores, Constant Shoulder Scores and visual analog scale for pain (pVAS) scores.
Before surgery, the initial tendon height was 7.4±1.5 mm in the no-deformity group and 9.3±2.0 mm in the deformity group. Follow-up height was 6.3±2.1 mm in the no-deformity group and 6.4±1.6 mm in the deformity group. Postop mean tendon heights were 90.1%±23.8% of the initial height in the no-deformity group and 73.2%±15.1% in the deformity group.
According to the researchers, there were no significant differences in ASES, Constant and pVAS scores observed between the two groups at 6 months. There was also no difference in re-tear rate (p > .999). Four shoulders in each group experienced re-tearing.
The researchers wrote, “Most deformities after rotator cuff repair were remodeled with no effect on re-tears. Clinical outcomes were not affected by deformities.”
