Introduction

The use of reverse total shoulder arthroplasty (RSA) is becoming increasingly common in the treatment of rotator cuff arthropathy. Standard RSA technique involves medialising the centre of rotation (COR) maximising the deltoid lever arm and compensating for rotator cuff deficiency. However reported complications include scapular notching, prosthetic loosening and loss of shoulder contour. As a result the use of Bony Increased Offset Reverse Shoulder Arthroplasty (BIO-RSA) has been gaining in popularity. The BIO-RSA is reported to avoid these complications by lateralising the COR using a modified base plate, longer central post and augmentation with cancellous bone graft harvested from the patients humeral head.

Introduction

The use of reverse total shoulder arthroplasty (RSA) is becoming increasingly common in the treatment of rotator cuff arthropathy. In recent years indications for use have expanded to include elderly patients in whom either internal fixation is not possible due to fracture configuration, poor bone quality, or presence of a rotator cuff deficiency. There is however relatively little evidence to support its use in these circumstances.

4 years of follow-up study on 27 patients who had biological reverse total shoulder replacement 12 patients who had Bio-RSA by using Tonier Aequalis reversed implants with bone graft extracted from the head of humerus before humeral shaft was prepared. The average age of this group of patients is 77. The average pre-operative shoulder abduction on the affected side is 52 degrees and forward flexion of 90 degrees. Indication for surgery in all those cases are due to cuff tear. The average post-operative abduction is 90 degrees and forward flexion of 97 degrees. The average follow-up period is 9 months with a range from 4 to 18 months. Two patients from this group failed to make an improvement in the range of their shoulder movements post-operatively.

15 underwent Bio-RSA by using Delta XTEND reverse shoulder system without bone graft. The average age of this group of patients is 73. The average pre-operative shoulder abduction is 35 degrees and forward flexion of 37 degrees. Indication for surgery again in most of the cases is due to cuff tear, except one case was due to proximal humeral fracture. The average post-operative abduction is 96 degrees and forward flexion of 101 degrees. The average follow-up period is 19 months with a range of 4–42 months. Only one patient failed to make an improvement post-operatively. This is the patient who had Bio-RSA due to a proximal humeral fracture. 6 patients out of this group also had previous resurfacing which has failed in comparison to the bone graft group which none had previous resurfacing surgery.

We undertook 37 reverse total shoulder replacements within a 2 yr period for chronic complex shoulder conditions. All cases were undertook by one of two upper limb consultant orthopaedic surgeons. At time of listing for operation, the decision as to whether to undertake a bony-increased offset reverse total shoulder was made. Retrospective data was collected on the need for analgesia at final follow up and range of movement.

Of the 37 patients, 12 underwent BIO-RSA procedures. Indications for surgery was predominantly rotator cuff arthropathy (n=9) but two patients had severe OA and one had a complex proximal humeral fracture. The average age of the patient was 76.6 yrs (69–87 yrs) with a mean follow-up of 6.8 months (6 weeks to 1 yr).

The remaining 25 patients were similar in terms of indication, with 18 patients with cuff tear arthropathies and 7 with severe OA. Average age was slightly lower at 74.9 years (50–85).

In terms of range of movement, outcomes between the two groups were broadly similar; those receiving BIO-RSA having an active forward flexion of 90.5° (50–130°) and abduction 88.6° (40–160°). Both groups had excellent analgesic effect with 92% in each either being completely painfree (33.3% BIO-RSA and 44% RSA) or requiring only occasional analgesia. The vast majority of patients were either very satisfied or satisfied with the outcome of the surgery, with one patient in the BIO-RSA group being slightly dissatisfied and three in RSA group.

If grafting is necessary, the use of BIO-RSA within this centre seems to have comparable results to those undergoing standard RSA.

Whilst the use of reverse total shoulder arthroplasty is becoming more common for the treatment of rotator cuff arthropathy, there is still relatively little evidence with regards to its use in complex fractures of the proximal humerus in the elderly. It is increasingly felt to be of use in those patients in whom either internal fixation is not possible due to fracture configuration or bone quality, or in whom there is a rotator cuff deficiency.

We report the outcomes of 14 patients with complex 3- or 4-part humeral fractures or delayed presentation of dislocation treated with reverse TSR. Patients were treated within a two year period from January 2011 to December 2013. The average age at time of operation was 75 (50–91 years) with a mean follow-up of 7 months (2–13 months). One patient moved out of area and one lost to follow-up two months following procedure.

Reverse TSR was considered a salvage procedure for patients with comminuted proximal humeral fractures or those who presented with irreducible non-acute dislocations. At time of last follow-up all 14 patients were satisfied with the results of their operation and functionally independent with activities of daily living. Range of movement post-operatively was good with mean active forward extension 97° (70–150°) and abduction 101° (80–170°). 43% of patients were pain-free, whilst the remainder only required the use of occasional analgesia. No major post-operative complications were reported.

Patients who underwent reverse TSR for dislocation fared better than for those with proximal humeral fractures. The mean active forward extension was 107.5° (90–150°) and abduction 112.5° (90–170°) in the dislocation group (n=5) compared with those who had a fracture in which the forward extension was 91.4° (70–120°) and abduction 95° (80–120°).

The results of these patients demonstrate that reverse TSR should be considered in patients with complex proximal humeral fractures or delayed presentation of fractures. It seems to provide consistently excellent pain-relief for patients, with patients either reporting being pain-free or requiring only occasional analgesia. In addition, all patients treated were functionally independent following operation. Range of movement, particularly for those with dislocation, appear good. Further follow-up is required to ensure sustained results but early studies are encouraging.