Introduction and Aims: To determine differences in rotator cuff tissue with duration of symptoms and tear size

Method: Rotator cuff tissue was obtained at debridement from 44 patients undergoing surgical repair. Pathological assessment was performed on H& E sections. Features evaluated included inflammation, micro-calcification, tendolipomatosis and fibroblast hypocellularity. Matrix quality and endothelial cell proliferation were examined. Patient details – age, tear size and duration of symptoms were extracted from notes.

Results: Matrix quality was significantly worse in small tears (p=0.028), particularly the extent of mucoid degeneration in the debrided tissue (p=0.017). Presence of a healthy cut margin was more likely in a large tear (10/14). Poor matrix was significantly associated with symptom duration > 15months (p=0.006) especially microcalicification (p=0.019) and mucoid degeneration (p=0.047). Endothelial cell proliferation was significantly more apparent in patients with longer duration of symptoms: previous vascular tufting (p=0.001) and ongoing vascular proliferation (p=0.019). Of 27 patients > 15months symptoms, vascular proliferation was strongly correlated with split collagen fibres (p< 0.018) and mucoid degeneration (p< 0.018) but not microcalcification. Tendolipomatosis was strongly correlated with ongoing vascular proliferation (p< 0.0006).

Conclusion: Successful surgical repair is only achieved in 30% patients with rotator cuff tears. Improvements in this success rate will be essential in order to maintain the independent lifestyle of an elderly population. Although the tissue examined here is debrided, and hence worst case tissue, several time-dependent processes are ongoing, degeneration, repair and remodelling. Matrix quality is deteriorating, however, this maybe supportive of the angiogenic component of repair. Remodelling may be seen in the increased probability of a healthy cut margin from patients with longer symptom duration.

Introduction and Aims: To determine whether non-steroidal anti-inflammatory drugs (NSAID) administration influences ongoing endothelial cell proliferation in tom rotator cuff?

Method: Rotator cuff tissue, obtained at debridement from 53 patients undergoing surgical repair, was fixed and embedded. Pathological assessment was performed on H& E sections. Ongoing vascular proliferation was identified by plump endothelial cells and budding of vessels. Patient cuff details and pre-operative drug prescription data was obtained from patients’ notes and by telephone from general practitioners. The drugs used were NSAIDs (including Aspirin, Ibuprofen and Diclofenac), COX 2 inhibitors and Opiates. The data was analysed using the SPSS program and the Pearson Chi-square test.

Results: Of the 35 patients taking analgesics, vascular proliferation was absent or reduced in 22 (63%). Twenty of these patients were taking NSAIDs. Four patients were taking only COX-2 inhibitor drugs; all these patients had increased vascularity. Twenty-three patients were taking codeine-based analgesics. Of 10 patients using codeine without NSAIDs, eight demonstrated active ongoing vascular proliferation (p=0.027).

Conclusion: Patients taking NSAIDs showed a significant reduction in ongoing vascular proliferation. If endothelial cell proliferation is an important component of repair in either the onset or post-operative stages of rotator cuff pathology, then attempts at repair could be compromised by inadequate local function of the vascular system. We have previously identified strong p27 positivity in rotator cuff endothelial 0 cells. NSAIDs can impair healing by inhibiting angiogenesis; the mechanism includes upregulation of p27 in endothelial cells. More work should be done to clarify this matter in the rotator cuff.

Purpose: To determine whether administration of non-steroidal anti-inflammatory drugs (NSAID) influences ongoing endothelial cell proliferation in torn rotator cuff?

Methods: Rotator cuff tissue, obtained at debridement from 53 patients undergoing surgical repair, was fixed and embedded. Pathological assessment was performed on H& E sections. Ongoing vascular proliferation was identified by plump endothelial cells and budding of vessels. Patient cuff details and preoperative drug prescription data was obtained from patient’s notes and general practitioners. The drugs considered were NSAIDs (including Aspirin, Ibuprofen and Diclofenac), COX 2 inhibitors & Opiates.

Results: Of the 35 patients taking analgesics, vascular proliferation was absent or reduced in 22 (63%). 20 of these patients were taking NSAIDs. Four patients were taking only COX-2 inhibitors, all these patients had increased vascularity. 23 patients were taking codeine based analgesics, of 10 patients using codeine without NSAIDs, 8 demonstrated active ongoing vascular proliferation (p=0.027).

Conclusion: Patients taking NSAIDs showed a significant reduction in ongoing vascular proliferation. If endothelial cell proliferation is an important component of repair processes in rotator cuff, this could be compromised. NSAIDs can impair healing by inhibiting angiogenesis, the mechanism includes upregulation of p27 in endothelial cells. We have peviously identified strong p27 positivity in rotator cuff endothelial cells.

Introduction: The rotator cuff is subject to constant pressure from the head of the humerus. This tends to ‘wring out’ the blood supply resulting in a functionally avascular critical zone, although microvessels can be identified. This zone is the site of degeneration and tears. Damage repair under these conditions would be difficult. Myofibroblasts are characteristic of the contractile phase of wound healing. We have examined their distribution in both healthy resected and torn, degenerating rotator cuff tissue and correlated their presence with vascularity and hypoxia in the surrounding tissue. Methods: Rotator cuff tissue was obtained from ten patients undergoing surgical repair. The size of tear was 1–4.5cm, Immunohistochemical staining with commercial monoclonal antibodies to HIF-1α (Hypoxia inducible factor), vimentin, smooth muscle actin (SMA), CD31 and VEGF was performed on formalin fixed paraffin embedded tissues. Visualisation used standard DAB chromagen technique. Results: Focal myofibroblast positivity (SMA+/VIM+) was detected, areas of positivity were found at the interface between torn and degenerating tissues adjacent to the tear. Myofibroblasts were absent in degenerating tissue. The areas of myofibroblast positivity were well vascularized, with strong VEGF positivity. Nuclear HIF-1α positivity was identified in the adjacent endothelial cell population and sporadically in fibroblast population, although not in the myofibroblasts. Conclusion: Evidence of an ongoing wound healing response was found in tissue from torn rotator cuffs. However, it was patchy and infrequent.

Background: Microvessels have been identified in the functionally avascular critical zone of the rotator cuff. Inadequate local sprouting of these capillaries might impair attempts at repair. We have identified widespread VEGF positivity in endothelial cells. However, this was accompanied by strong positivity for the cell cycle inhibitor p27 and little proliferation (Ki-67 positivity). Non-steroidal anti-inflammatory drugs (NSAID) can impair healing by inhibiting angiogenesis. The mechanisms include upregulation of p27 in endothelial cells. Objective: Does NSAIDs influence endothelial cell proliferation in torn rotator cuff? Methods: Pathological assessment of Rotator cuff tissue, obtained from 35 patients undergoing surgical repair, was performed on H& E sections. Ongoing vascular proliferation was identified by plump endothelial cells and budding of vessels. Preoperative drug prescription data was obtained from patient’s General practitioners. The drugs used were NSAIDs (including Ibuprofen and Diclofenac), COX2 inhibitors & Opiates. Results: Ongoing vascular proliferation was not identified in 20/35 patients. 25 patients were taking analgesics; vascular proliferation was absent in 15. 20 patients were taking NSAIDs of these 15 demonstrated no ongoing vascular proliferation, (p≤0.014). No significant effect of opiates or COX2inhibitors was found. Discussion: Patients taking NSAIDs showed a significant reduction in vascular proliferation. If endothelial cell proliferation is an important component of repair in rotator cuff tears, more work should be done to clarify this matter.