The incidence of frozen shoulder (FS) as a complication of simple arthroscopic shoulder surgery has yet to be defined. A single-surgeon case series of patients undergoing arthroscopic subacromial decompression (ASD) or ASD with arthroscopic acromioclavicular joint (ACJ) excision was analysed to establish FS rate, this cohort was then compared to a matched group of primary FS patients. Retrospective analysis of 200 consecutive cases was undertaken. All procedures listed, performed and reviewed by the senior author. 96 underwent ASD and 104 underwent ASD and ACJ excision. 6-months follow-up minimum. Incidence of frozen shoulder was 5.21% (ASD) and 5.71% (ASD+ACJ excision). Mean age was 52.3 years (95% CI: 47.4 to 57.2) of the patients that developed FS, compared to 57.2 years (95% CI: 55.2 to 59.2) in the patients who did not and 52 years (95% CI: 50.7 to 53.3) in the primary FS cohort (n=136). 9.1% of post-operative FS were diabetic compared to 17.1% of primary FS. 63.6% were female in the post-operative FS group, 47.1% in the primary FS group. Our results suggest that the risk of FS following simple arthroscopic procedures is 5%, with no increased risk if the ACJ is also excised. This cohort has the same average age as a primary FS. There is a trend toward female sex and diabetes does not increase the risk

Use of shoulder manipulation in the treatment of frozen shoulder (FS) remains controversial. One of the purported risks associated with the procedure is the development of a rotator cuff tear. However the incidence of iatrogenic rotator cuff tears has not been reported. The purpose of the study was to assess the effect of manipulation of the shoulder on the integrity of the rotator cuff. In a prospective study 20 consecutive patients (21 shoulders) with FS underwent manipulation of the shoulder under anaesthesia (MUA). The average duration of symptoms was 7.3 months (4–18 months). Patients were assessed pre and post manipulation using the Constant score. An ultrasound scan of the rotator cuff was performed before and at 3 weeks after manipulation. In all patients, pre and post manipulation ultrasound scans showed the rotator cuff to be intact. At 12 weeks after manipulation all patients indicated that they had none or only occasional pain. The mean improvement in motion was 83 degrees (range, 20 – 100°) for flexion, 95 degrees (range, 20 – 120°) for abduction, 58 degrees (range, 0 – 80°) for external rotation and 3 levels of internal rotation (range 3–5 levels). These gains in motion were all significant (p < 0.01). No fractures, dislocations or nerve palsies were observed. In conclusion manipulation under anaesthesia for treatment of frozen shoulder resulted in significant improvements in shoulder function and pain relief as early as 3 weeks after surgery and was not associated with rotator cuff tears. When performed carefully this procedure is safe and leads to early improvements in pain relief, range of movement and shoulder function

In patients with DM (Diabetes Mellitus types I & II), primary frozen shoulders tend to be refractory to all forms of treatment. We collected tissue from the joint capsule of shoulder joints from a variety of patients undergoing surgery as follows:. Diabetic Group (DFS): patients with DM who have primary frozen shoulders. Other patients suffering from primary frozen shoulders (FS). Control group (NS). Patients undergoing shoulder surgery that does not involve stiffness of the gleno-humeral joint. Tissue was collected from near to the rotator interval under arthroscopic control. Fibroblast lines were established by serial passage. Thereafter they were exposed to graded concentrations of insulin in vitro for 24 hours and the supernatant retained for assay. Fibroblast lines were analysed from 3 subjects in each group (n=9). Luminex multiplex analysis was performed for MMPs (Matrix Metalloproteinases). TIMP-1 (Tissue Inhibitor of MetalloProteinases) expression. Informed consent was obtained from all subjects. Results: Production of MMP 1,2,3 and 8 by fibroblast lines were distinct between patient groups. MMP-1 production in DFS (mean 716pg/mL) was significantly reduced compared to FS derived patient cells (mean 972pg/mL) (p=0.0138, Mann-Whitney Test). Moreover, striking differences were observed when fibroblasts from DFS patients were compared with those from NS controls (mean 5898pg/mL) (p< 0.000). Calculating MMP-1/TIMP-1 ratios revealed significantly lower ratios in DFS (2597), or FS (2860) compared with NS (24,326) (p < 0.001). There was no significant difference between ratios of MMP1/TIMP1 in DFS and FS (p=0.977). MMPs 7,9,12 and 13 were not detected in any of the samples. This is the first time these enzymes have been measured and quantified in cells derived from shoulder tissues. Primary Frozen Shoulders produce less MMPs and have a smaller MMP/TIMP ratio than controls. Similarly the diabetic patient derived cells produce less MMP-1, at an even lower level. These deficiencies in MMP1 production may reflect an altered capacity for local tissue re-modelling. MMP modulation may allow therapeutic intervention in the diabetic and frozen shoulder group of patients

Frozen Shoulder (FS) is a debilitating musculoskeletal condition with an uncertain aetiology and poorly understood pathogenic mechanism. This study aimed to investigate the pathology of FS. We hypothesised that an altered expression of cytokines may disrupt the normal tissue remodeling process, leading to FS, which would be apparent histologically. Patients undergoing arthroscopic treatment of FS were prospectively recruited, along with control patients being treated for subacromial impingement. Synovial biopsies were taken from all subjects. Synovial RNA levels were analysed using quantitative Polymerase Chain Reaction (qPCR). Inflammatory cytokines and growth factors thought to play a role in the pathogenesis of FS were assessed. These included metalloproteases (MMP, ADAMTS) involved in tissue remodeling and fibrosis, inflammatory cytokines such as interleukins (IL), and growth factors such as colony stimulating factors (MCSF, GMCSF, CSF1R). Samples underwent histological analysis, to assess inflammation and fibrosis. Thirteen patients with FS and ten control patients with subacromial impingement were recruited. Arthroscopic inspection revealed greater levels of synovitis (2.63+ vs 0.40+, p< 0.01) and papillary proliferation (50% vs 10%, p=0.02) in FS patients compared with the control group, confirming the initial clinical diagnosis of FS. Histological analysis of the synovium revealed samples from the FS group were more likely to demonstrate a fibrotic, focally nodular collagen morphology (53.8% vs 10%, p=0.03). There were similar levels of chronic inflammatory cells present in those with FS and control patients (53.8% vs 30%, p=0.25). There was no evidence of acute inflammation in any of the samples. Immunohistochemical staining revealed a high level of AGEs present in the synovium and smooth muscle tissue in all samples. There was no observed difference between diabetic and non-diabetic samples. Cytogenetic analysis using qPCR revealed fibrogenic factors MMP3 (p=0.068), and ADAMTS4 (p=0.083) to be elevated in FS cases, as were inflammatory cytokines IL6 (p=0.062) and IL8 (p=0.075). We have quantified the level of inflammatory cytokines and growth factors in FS, demonstrating that these factors are elevated in FS. This indicates that altered levels of inflammatory cytokines may be associated with the pathogenesis of inflammation evolving into fibrosis, the characteristic feature of FS. We have also shown the histology of this fibrosis to be different to that observed in normal synovium