Sunday, April 1, 2018

Revision of failed anatomic total shoulder arthroplasty to hemiarthroplasty

The revision of the failed anatomic total shoulder arthroplasty (TSA) to a reverse is not ideal for the young active patient. The reason is that the reverse TSA is a reconstructive procedure that can provide restoration of function for those cases for a limited timeframe.  There is no further reconstruction that can be offered once the reverse TSA fails which is usually 5-10 years after the surgery. Thus, for the young patient (age in 50s- early 60s) the preferred revision is conversion to a hemiarthroplasty. More importantly, when the rotator cuff is intact it is preferred to avoid conversion to a reverse TSA. 

The following case illustrates an example of conversion of a failed TSA to a hemi. The failure was within 2 years from the index procedure and the patient was referred to us after his surgery for a painful stiff shoulder.

The prosthesis was "proud" and there was excessive amount of cement on the glenoid side and the glenoid component was loose. Four out of the six cultures indicated p.acnes infection with a normal preoperative lab work and no wound problems prior to revision surgery. These cultures became positive on day 7 and the patient was placed on Augmentin 875 BID prophylactically on day 1 as there was a suspicion of infection as well. Despite the positivity of the cultures, the one stage revision to a hemi-arthroplasty resulted is complete relief of pain on postoperative day 10 and no use of pain medication. 

As seen on the x-rays below the "proud" stem was the result of oversizing the stem diameter, which resulted in proximal distal fixation, incomplete advancement of the implant in the endosteal canal and a "proud" position of the humeral head.  In other words, the stem could not be advanced further into the canal as the distal portion of it engaged fully into the canal prior to complete seating proximally.

In this case, vertical osteotomy of the humerus was performed for extraction of the humeral stem and re-implantation of a smaller in diameter stem which allowed anatomic fixation and complete seating of the humeral head.

The excessive cementation of the glenoid as seen in the clinical photos is an independent factor for early failure as demonstrated by the work done at the UW Medical Center in Seattle, WA.

Suggested reading: 
Hackett DJ Jr, Hsu JE, Matsen FA 3rd. 
Primary Shoulder Hemiarthroplasty: 
What Can Be Learned From 359 Cases 
That Were Surgically Revised? Clin Orthop Relat
Res. 2018 Feb 21




Grashey view prior to index procedure



Failed anatomic TSA, loose glenoid component and proud humeral prosthesis due to "oversized" distal diameter of the stem which does not permit advancement in the endosteal canal.


Revision to hemi with undersized stem after vertical proximal humerus osteotomy and repair of the osteotomy side with four No 2 Fiberwire sutures.



Excessive cementation of the glenoid component, early loosening without fracture or wear or perforation.