What Influence Does Progression of a Nonhealing Rotator Cuff Tear Have on Shoulder Pain and Function?

Abstract

There have been numerous reports of clinical outcomes associated with tendon healing after repair that suggest a nonhealed tendon has a negative effect on postoperative clinical outcomes. However, to our knowledge, there has been no report on the relationship between tear size progression of nonhealed tendons and clinical outcomes. (1) Do patients with healed arthroscopic rotator cuff repairs have better outcomes, less pain, and more strength than patients whose repair did not heal? (2) In patients with nonhealed rotator cuff tendons, does tear size progression (increase or decrease) affect outcomes, pain, and strength? (3) Is there continued improvement beyond 6 months in outcomes, pain, and strength; and how do the improvements differ based on whether the tear size has increased or decreased? Between May 2008 and December 2012, 647 patients underwent arthroscopic rotator cuff repair for full-thickness tears at our institution. Of those, 442 patients (68%) had all MRI and clinical information available to permit inclusion in this retrospective study at a minimum of 2 years followup (mean, 33 ± 4 months; range, 24-43 months). Healing of the repaired tendon and tear size progression were assessed using MRI at 6 months postoperatively. Eighty-two of 442 tears (19%) were not healed. Of the nonhealed tears, 45 (55%) had a decrease and 37 (45%) had an increase in tear size. Shoulder function outcomes using the American Shoulder and Elbow Surgeon (ASES) and Constant scores and pain severity using VAS scores were evaluated preoperatively, at 6 months postoperatively, and at the latest followup. Isometric muscle strength was measured at 6 months postoperatively and at the latest followup. Compared with patients with nonhealed tendons after arthroscopic rotator cuff repair, patients with healed repairs had improved ASES scores (healed, 93 ± 5; nonhealed, 89 ± 8; mean difference, 4; 95% CI, 3-5; p < 0.001), better Constant scores (healed, 91 ± 5; nonhealed, 85 ± 8; mean difference, 6; 95% CI, 4-7; p < 0.001), and greater strength ([flexion: healed, 96% ± 7%; nonhealed, 85% ± 12%; mean difference, 11%; 95% CI, 9%-13%; p < 0.001]; [external rotation: healed, 92% ± 8%; nonhealed, 80% ± 12%; mean difference, 11%; 95% CI, 9%-14%; p < 0.001]; [internal rotation: healed, 97% ± 8%; nonhealed, 92% ± 8%; mean difference, 5%; 95% CI, 3%-7%; p < 0.001]); however there was no difference in pain level based on VAS scores (healed, 0.9 ± 0.8; nonhealed, 1.0 ± 0.8; mean difference, 0.2; 95% CI, 0.0-0.4; p = 0.226). Compared with patients with increased tear size, patients with decreased tear size had better ASES scores (decreased, 91 ± 6; increased, 8 6 ± 8; p = 0.001), improved Constant scores (decreased, 88 ± 6; increased, 82 ± 9; p = 0.003), greater flexion strength (decreased, 91% ± 9%; increased, 78% ± 11%; p < 0.001), and greater external rotation strength (decreased, 86% ± 10%; increased, 73% ± 11%; p < 0.001). However, the difference does not seem to meet a minimal clinically important difference. Patients with increased tear size differed from those with decreased tear size with respect to flexion and external rotation strength where the former had no improvement. There was no improvement in flexion (6 months, 78% ± 11%; latest followup, 78% ± 11%; p = 0.806) and external rotation strength (6 months, 74% ± 12%; latest followup, 73% ± 11%; p = 0.149). Patients who had healed tendons after arthroscopic rotator cuff repair had better shoulder function than patients who had nonhealed tendons. Among patients with nonhealed rotator cuff tendons after surgery, those with decreased tear size, observed on their 6-month postoperative MRI, compared with their initial tear size, showed better shoulder function and muscle strength than those with increased tear size beyond 6 months. Although results are statistically different, they seem insufficient to achieve clinically important differences. Level III, therapeutic study.