The aetiology and pathophysiology of frozen shoulder is poorly understood. The macroscopic pathological finding is dense fibrosis of the glenohumeral capsule and ligaments. Cellular histological studies reveal active proliferation of fibroblasts and their transformation to myofibroblasts, resulting in a dense matrix of disorganised collagen, causing capsular contracture. To further elucidate these pathological changes we arthroscopically examined 45 consecutive frozen shoulders immediately prior to performing arthroscopic release. The distinctive finding in all cases was new blood vessel formation or angiogenesis in the synovium and capsule. There were five distinct angiogenic patterns: 1.vascular synovial proliferation at the base of the anchor of the long head of biceps tendon (most common); 2.petechial haemorrhagic spots widely spread across the synovium, in the rotator interval and even on the labral surface; 3.capillary loops and spirals, appearing like “lava flow”; 4.dense red vascular synovitis; 5.spectacular capillary whorls, similar in appearance to glomeruli (least common). High quality arthroscopic digital images will illustrate these findings. The vascular changes seen in the shoulder joint in frozen shoulder are pathognomonic and similar to those seen in the formation of hypertrophic and keloid scarring of the skin, diabetic retinopathy, a variety of auto-immune disorders and tumours, rheumatoid arthritis and many other disease processes. The ability to therapeutically inhibit angiogenesis via inhibition of cytokines or adhesion molecules in these diseases suggests a possible role for these developing non-surgical treatments in frozen shoulder.
Displaced proximal humeral fractures are notoriously difficult to treat. We performed internal fixation of 55 such fractures with the Polarus locked intramedullary nail. 43 (78%) were women; the mean age was 74 (range 15–91). The mechanism of injury was RTA in four, sporting injury in a further four and a simple fall in 47 (85%). According to Neer’s classification, 25 were two part fractures, 20 three part and 10 four part. 47 fractures were fixed acutely (within seven days). The average operative time, including patient positioning was 60 minutes. In 43 cases the standard size nail was used (11mm diameter, 150mm length). In the majority of cases (80%) either two or three proximal locking screws were used. In 15 cases (27%) open reduction was necessary. Patients were followed up for an average of eight months. Three patients needed removal of backed out proximal screws under local anaesthetic. In one patient the nail migrated superiorly and was removed once the fracture had united. One patient developed symptomatic avascular necrosis of the humeral head, successfully treated by removing the proximal screws. Two patients developed fracture malunion and underwent conversion to hemiarthroplasty. One patient required arthroscopic release of a secondary frozen shoulder. Patients completed an Oxford Shoulder questionnaire at an average of 18 months postoperatively (range 5–42 months). The median Oxford Shoulder score was 33 (95% CI 25–38) with a mean score of 34.6 Previous studies of Polarus nailing have reported satisfactory results, but with limited follow up of a small number of patients. Our study of 55 cases with an average 18 month follow up confirms good functional rapid recovery in the majority of patients. Only five patients required removal of the metalwork and only two patients required conversion to hemiarthroplasty. We recommend the Polarus nail as a useful addition to the shoulder trauma surgeon’s armamentarium.
