Does microvascularization of the footprint play a role in rotator cuff healing of the shoulder?

ABSTRACT

BACKGROUND: The aim of the study was to evaluate the relationship between bone microvascularization of the footprint and tendon integrity after rotator cuff repair of the shoulder. METHODS: Forty-eight patients (mean age, 59 years; ±7.9) with a chronic rotator cuff tear underwent a tendon repair with a single-row technique and were studied prospectively. A core obtained from the footprint during the procedure allowed determination of the bone's microvascularization with an immunohistochemistry technique using anti-CD34 antibodies. Clinical evaluation was performed at a minimum of 12-month follow-up, and rotator cuff integrity was assessed with ultrasound according to Sugaya's classification. RESULTS: At a mean follow-up of 13 months, the Constant score improved from 40 to 75 points; American Shoulder and Elbow Surgeons score, from 59 to 89 points; and subjective shoulder value, from 38% to 83% (P < .001). Ultrasound identified 18 patients with Sugaya type I healing, 27 patients with type II, and 3 patients with type IV. No patients showed Sugaya type III or V repairs. The rate of microvascularization of the footprint was 15.6%, 13.9%, and 4.2% for type I, II, and IV tendon integrity, respectively (I vs. II, P = .22; II vs. IV, P = .02; I vs. IV, P = .0022). Patients with a history of corticosteroid injection had a lower rate of microvascularization than the others (10.3% vs. 16.2%; P = .03). CONCLUSIONS: Even if overall satisfactory clinical outcomes are achieved after a rotator cuff repair, bone microvascularization of the footprint plays a role in rotator cuff healing. A lower rate of microvessels decreases the tendon integrity and healing potential after repair.