Abstract

The aim of this study was to determine cell viability in different stages of rotator cuff tendon tears using a cell viability molecular probe. Surgical biopsies taken from the edge of the Supraspinatus tendon tear from12 patients, 5 women and 7 men, mean age of 61 years were subjected to a cell viability assay using Molecular Probes Live/Dead cell viability assay. Specimens were then incubated with Calcein-AM and Ethidium Homodimer-1 and following snap freezing, sections were viewed under fluorescent microscopy. Cells which remained metabolically active fluoresced green, whereas dead cells were red. Populations of live and dead cells were counted for each specimen on ten high powered (x400 magnification) fields of view. The results show that the percentage of live cells is reduced in large chronic degenerate tears but greatest in acute traumatic tears. In addition, for those cases where tissue was assayed from the edge of the tear and 1 cm more proximally, there was a considerable increase in the percentage of viable cells in more proximal tissue. Use of this simple assay demonstrates high cell viability and consequently good quality tissue in traumatic tears, but lower quality tissue in larger more degenerate tears. This suggests that traumatic lesions have a high propensity to heal while larger more degenerate tears are less likely to heal but have better quality tissue more proximally.

The aim of this study was to observe cellular and vascular changes in different stages of full thickness rotator cuff tear.

Biopsies of the Supraspinatus tendon in 40 patients with chronic rotator cuff tears undergoing surgery were analysed using histological and contempary immunocytochemical techniques. Sections were stained with primary antibodies against PCNA (Proliferating cell nuclear antigen), CD34 (QBEnd 10), CD45 (Leucocyte Common Antigen), CD68, D2-40 (Lymphatic Endothelial Marker) and Mast Cell Tryptase. A histological analysis was performed with Mayer’s Haemotoxylin and Eosin, Congo Red and Toluidine Blue.

The reparative response and inflammatory component (figure 1) of the tissue was seen to diminish as the rotator cuff tear size increased. This was evidenced by increasing degeneration and oedema, reducing fibroblast proliferation, reduced thickening of the synovial membrane and reducing vascularity. Macrophage, other leucocyte and mast cell numbers also reduced as tear size increased. Large and massive tears revealed a higher degree of chondroid metaplasia and amyloid deposition when compared to smaller sized tears. There was no association with the patient’s age or duration of symptoms.

Small sized rotator cuff tears retain the greatest potential to heal and have a significant inflammatory component. Tissue from large and massive tears is of such a degenerate nature that it may never heal and this is probably a significant cause of re-rupture after surgical repair in this group. Selection of patients for reconstructive surgery should take into account the composition and healing potential of tendon tissue and its relationship to tear size in chronic tears of the rotator cuff.

A prospective study was carried out to determine if recognised histological features seen at surgery could help predict those rotator cuff tendon repairs which re-ruptured. 40 rotator cuff tendon edge specimens from 40 patients’ shoulders were analysed histologically following routine mini-open rotator cuff repair. 32/40 underwent Ultrasonography, at a mean time of 35 months post-operatively, to determine repair integrity. The histological features seen at surgery were then compared to the repair integrity of the tendon from which it had been taken. Rotator cuff repairs that remained intact demonstrated a greater reparative response, in terms of increased fibrobast cellularity, cell proliferation and a thickened synovial membrane, than those repairs which reruptured. Larger tears which remained intact showed a higher degree of vasacularity and a significant inflammatory component than those that re-ruptured. Good tissue quality at the time of surgery allows the repair the best chance of remaining intact despite the size of the lesion. Routine histological analysis of the tissue biopsy, preformed in the post-operatively, can now aid the clinician in terms of early management and repair prognosis.

We treated 22 patients with a diagnosis of primary frozen shoulder resistant to conservative treatment by manipulation under anaesthetic and arthroscopic release of the rotator interval, at a mean time from onset of 15 months (3 to 36). Biopsies were taken from this site and histological and immunocytochemical analysis was performed to identify the types of cell present. The tissue was characterised by the presence of fibroblasts, proliferating fibroblasts and chronic inflammatory cells. The infiltrate of chronic inflammatory cells was predominantly made up of mast cells, with T cells, B cells and macrophages also present.

The pathology of frozen shoulder includes a chronic inflammatory response with fibroblastic proliferation which may be immunomodulated.

Aim To determine if tissue metabolism varies in supraspinatus tendons with distance from the edge of the rotator cuff tendon tear and also with differing size of tear.

Background Tissue metabolism can be assessed by measuring oxygen and nitrous oxide concentrations within the tissue. Viable tendon tissue consumes oxygen and contains nitrous oxide (used in the general anaesthetic) from the blood stream. Non-viable tendon tissue will not consume oxygen but will contain nitrous oxide.

Methods Oxygen and Nitrous Oxide concentrations were measured amperometrically using silver needle microelectrodes.

The needle was inserted into the supraspinatus tendon of patients with massive, large, medium and small full thickness rotator cuff tears and patients with partial thickness and no tears. Patients undergoing open stabilisation were used as controls. Measurements were made at a number of quantifiable points from the tendon edge to allow the creation of a topographical map of tissue metabolism. Oxygen consumption was calculated using measured oxygen and nitrous oxide levels at each point.

Results In patients with rotator cuff tears oxygen consumption was significantly lower near to the edge of the tear.

Patients with impingement syndrome but no evidence of a rotator cuff tear also showed a decreased level of oxygen consumption in the anterior part of supraspinatus, but this was significantly higher than the levels seen in the torn tendon.

The control group showed no significant alteration in oxygen levels

Conclusion Patients with rotator cuff tendon tear demonstrate significantly reduced levels of tissue metabolism. This reduction in tissue viability is significantly greater at the edge of the tear and in larger tears. Patients with intact tendons and impingement syndrome also demonstrate minor reduction in tissue tendon viability compared with controls.

Arthroscopic shoulder surgery is evolving rapidly and several methods of stabilisation have been described. We present a simple new technique which addresses both the Bankart lesion and the capsular stretching together with the short-term results.

The technique can be performed using just one anterior working portal and one posterior viewing portal. The labrum and capsule are elevated from the anterior glenoid neck by sharp dissection. One suture anchor is placed at the half past four position. One suture limb is passed under the labrum at 6 o’clock, the other limb is passed under the labrum at 2 o’clock and the two ends are tied. This has a purse string effect, tightening the capsule in only the superior/inferior plane, which also creates a bumper of labrum at the anterior glenoid rim.

This technique was used in 35 patients (36 shoulders) with recurrent antero-inferior instability due to a traumatic Bankart lesion. The patient group included 33 men and 2 women with mean age 25 years (16–49). They had sustained an average of 5 dislocations per shoulder (1 to 11). The cohort included 4 professional and 6 semi-professional sportsmen all of whom were involved in collision or overhead sports. All the patients were assessed by an independent investigator at an average of 14 months (6–48) post surgery.

Only one patient developed recurrent instability. This occurred without sustaining trauma. The average postoperative Rowe score was 93 (55–100), Walch-Duplay score was 93 (70–100), and Constant score was 97 (77–100). 65% of patients returned to the same level of sports and all the professional athletes were able to resume full activities.

In conclusion, this technique is simple in concept, straightforward to perform, and demonstrates excellent short-term results.