Animal studies examining tendon-bone healing have demonstrated that the overall structure, composition, and organization of direct type entheses are not regenerated following repair. We examined the effect of Low-Intensity Pulsed Ultrasound (LIPUS) on tendon-bone healing. LIPUS may accelerate and augment the tendon-bone healing process through alteration of critical molecular expressions.

Eight skeletally mature wethers, randomly allocated to either control group (n=4) or LIPUS group (n=4), underwent rotator cuff surgery following injury to the infraspinatus tendon. All animals were sacrificed 28 days post surgery to allow examination of early effects of LIPUS. Humeral head – infraspinatus tendon constructs were harvested and processed for histology and immunohistochemical staining for BMP2, Smad4, VEGF and RUNX2. All the growth factors were semiquantitative evaluated. T-tests were used to examine differences which were considered significant at p < 0.05. Levene's Test (p < 0.05) was used to confirm variance homogeneity of the populations.

The surgery and LIPUS treatment were well tolerated by all animals. Placement of LIPUS sensor did not unsettle the animals. Histologic appearance at the tendon-bone interface in LIPUS treated group demonstrated general improvement in appearance compared to controls. Generally a thicker region of newly formed woven bone, morphologically resembling trabecular bone, was noted at the tendon-bone interface in the LIPUS-treated group compared to the controls. Structurally, treatment group also showed evidence of a mature interface between tendon and bone as indicated by alignment of collagen fibres as visualized under polarized light. Immunohistochemistry revealed an increase in the protein expression patterns of VEGF (p = 0.038), RUNX2 (p = 0.02) and Smad4 (p = 0.05) in the treatment group. There was no statistical difference found in the expression patterns of BMP2. VEGF was positively stained within osteoblasts in newly formed bone, endothelial cells and some fibroblasts at the interface and focally within fibroblasts around the newly formed vessels. Expression patterns of RUNX2 were similar to that of BMP-2; the staining was noted in active fibroblasts found at the interface as well as in osteoblast-like cells and osteoprogenitor cells. Immunostaining of Smad4 was present in all cell types at the healing interface.

The results of this study indicate that LIPUS may aid in tendon to bone healing process in patients who have undergone rotator cuff repair. This treatment may also be beneficial following other types of reconstructive surgeries involving the tendon-bone interface.

The diagnosis and treatment of disorders of the long head of the biceps tendon remains controversial. There is uncertainty as to the role of the long head of biceps and it can be difficult to determine whether the patient's pathology is coming from the biceps or other adjacent structures. In addition, the appropriate type of treatment remains controversial.

We retrospectively reviewed the files of the senior author's experience in over 4000 arthroscopic shoulder procedures. We examined cases involving isolated biceps pathology, excluding those patients with rotator cuff tears and labral pathology, involving 92 biceps tenotomies and 103 biceps tenodeses.

Our analysis supports the benefit of clinical examination over all types of radiological investigations. The benefits and technique of biceps tenodesis is described including surgical technique. Irritation by PLA interference screw is examined. A paradigm is put forward to help in diagnosis and management of these lesions.

Long head of biceps pathology is a significant cause of shoulder pain in association with other shoulder problems and in isolation. Biceps tenodesis and tenotomy is an efficacious way of dealing with this pathology.

The management of shoulder instability has changed a great deal in the last five years due to a better understanding of the biomechanics of the shoulder and the use of arthroscopic surgery.

It is essential to understand the anatomy of the labrum and bony structures of the shoulder joint, as well as the contribution of these structures as well as the Rotator Cuff to stability in the different positions of the arm. The history and examination still remains the most important diagnostic tool and a thorough history and examination cannot be over-emphasised.

MR Arthrography is the investigation of choice in confirming the diagnosis of instability while a CT scan may be required if there is significant bony damage.

The most controversial topic is that of the first time dislocator. If there is a significant labral tear then the options of an arthroscopic labral repair or external rotation brace need to be considered. In the absence of a labral tear then physiotherapy is the treatment of choice.

For recurrent dislocators, the results of arthroscopic labral repairs with capsular plication techniques are approaching those of the gold standard open stabilisation. If, however, there is significant bony damage to the glenoid or humeral head then a bone block procedure may be the treatment of choice.

Rotator Cuff tears need to be excluded in older patients with instability and often in such cases an arthroscopic procedure to deal with the Rotator Cuff and Labrum can be done simultaneously.

The transosseous equivalent/Suture Bridge or TOE/SB repair has received much attention in recent years as more shoulder surgeons transition to all arthroscopic rotator cuff repairs. The purpose of this study was to compare the biomechanical behaviour of several variants of the Suture Bridge repair performed by the authors.

Four different Suture Bridge constructs were performed six times on 24 sheep infraspinatus tendon humerus constructs. The first group was a standard Suture Bridge with two medial mattress stitches with knots (KSSB4). The second group had four medial mattress stitches with knots and was called KDSB8. The third group had two medial mattress stitches without knots and was called USBFT4. These first three repairs used two medial 5.5 mm Bio-Corkscrew FT Anchors and two lateral 3.5 mm PushLock Anchors (Arthrex). The fourth repair had two medial mattress stitches without knots and used all Pushlocks and was called USBP4.

The repairs were then analysed for failure force, cyclic creep and stiffnessafter. Cycling was performed from 10 to 100 N at 1 Hz for 500 cycles. Following cyclic testing a single cycle pull to failure at 33 mm/sec was performed. The constructs were also observed for failure mechanism and gap formation using digital video recording.

The KDSB8 repair with a mean failure force of 456.9N was significantly stronger than the USBP4 repair at 299.7N (P=0.023), the KSSB4 repair at 295.4N (P=0.019) and lastly the USBFT4 repair at 284.0N (P=0.011). There was no statistical difference between the measured failure force for the two mattress stitch KSSB4 repair with knots and the knotless two mattress stitch repairs USBFT4 and USBP4. There was not a statistical difference between any of the repairs for measured stiffness and cyclic creep. However, the KDSB8 repair showed no discernable gap formation or movement at the footprint during cyclic testing. The KSSB4, USBFT4 and USBP4 repairs demonstrated bursal sided gap formation in the range of 1 to 3 mm.

Based on the results of this study the transosseous equivalent/Suture Bridge repair with four stitches tied in the medial row and maximal lateral suture strand utilization (KDSB8 TOE/SB) is the strongest. The KDSB8 also appeared to show less bursal sided gap formation and greater footprint stability than the other Suture Bridge constructs tested.