Shoulder degeneration in the middle aged patient (age >40 <55 years old) in the form of degenerative osteoarthritis, traumatic arthritis, inflammatory arthropathy, capsulorraphy arthropathy and avascular necrosis is a difficult problem to solve due to the limitations in the longevity of the current implants available. The most common reasons for shoulder degeneration in the young patient (<40 years of age) are traumatic arthritis, capsulorraphy arthropathy and avascular necrosis. The following paper provides information on the longevity of the shoulder resurfacing arthroplasty in this challenging patient population.
A picture of a resurfacing implant is shown below
Bone Joint J. 2014 Apr;96-B(4):519-25. doi: 10.1302/0301-620X.96B4.31850.
Outcome, revision rate and indication for revision following resurfacing hemiarthroplasty for osteoarthritis of the shoulder: 837 operations reported to the Danish Shoulder Arthroplasty Registry.
Abstract
In this study, we evaluated patient-reported outcomes, the rate of revision and the indications for revision following resurfacing hemiarthroplasty of the shoulder in patients with osteoarthritis. All patients with osteoarthritis who underwent primary resurfacinghemiarthroplasty and reported to the Danish Shoulder Arthroplasty Registry (DSR), between January 2006 and December 2010 were included. There were 772 patients (837 arthroplasties) in the study. The Western Ontario Osteoarthritis of the Shoulder(WOOS) index was used to evaluate patient-reported outcome 12 months (10 to 14) post-operatively. The rates of revision were calculated from the revisions reported to the DSR up to December 2011 and by checking deaths with the Danish National Register of Persons. A complete questionnaire was returned by 688 patients (82.2%). The mean WOOS was 67 (0 to 100). A total of 63 hemiarthroplasties (7.5%) required revision; the cumulative five-year rate of revision was 9.9%. Patients aged < 55 years had a statistically significant inferior WOOS score, which exceeded the minimal clinically important difference, compared with older patients (mean difference 14.2 (8.8; 95% CI 19.6; p < 0.001), but with no increased risk of revision. There was no significant difference in the mean WOOS or the risk of revision between designs of resurfacing hemiarthroplasty. Cite this article: Bone Joint J 2014;96-B:519-25.
This article highlights the problem of high failure rate of the shoulder resurfacing at long term followup. A lot of surgeons prefer to use this implant for the treatment of shoulder avascular necrosis or osteoarthritis because of the following reasons
- Restoration of normal anatomy
- Less-traumatic surgery
- No risk of fat embolus from surgery trauma
- Resurfacing can be done even if the proximal humeral bone is deformed
- No risk of fracture at the tip of the prosthesis
- Quicker recovery with less pain
- Easy revision surgery if needed
In our experience the use of humeral head resurfacing has higher rates of complications. It a technically demanding operation and as highlighted in the paper above the rate of revision at 5 years postoperatively is 10%. We prefer to use a stemmed hemi-arthroplasty when there is concern about the longevity of the implant in young patient with shoulder degeneration. A picture of a hemi-arthroplasty implant is shown below.
The following case is a 48 y/o female who has been diagnosed with post-collapse avascular necrosis (AVN) of the humeral head. Her avascular necrosis is associated with oral steroid use for a dermatologic condition she had in the past. She had failed arthroscopic debridement and had active forward elevation of the shoulder to 110 degrees prior to surgery due to pain. Her preoperative x-rays show collapse and AVN of the humeral head with intact glenoid. She underwent a hemi-arthroplasty successfully with significant relief of symptoms. Her active forward elevation was to 140 degrees at 3 months after surgery.
A similar case is the following. This is a 49 year old male who has been diagnosed with osteoarthritis of the shoulder, has failed arthroscopic debridement and chondroplasty of the shoulder. He had prior to surgery active shoulder forward elevation to 140 degrees. The arthroscopic chondroplasty provided relief for about one year. We elected to proceed with shoulder hemi-arthroplasty due to his young age and the concerns of glenoid component loosening and revision in the long term. His preoperative and postoperative radiographs are shown below.
A glenoid component was not used in these two case examples because of the patients' age. If the patients were 60-65 years old or older then a glenoid component would have been used.
The following graph demonstrates the problem of glenoid component revision/failure over time.
If the option of total shoulder replacement is excluded then the question that remains to be answered is whether a hemi-arthroplasty or resurfacing implant should be used.
The Australian total shoulder replacement registry provides data on rates of revision. They report on 18,164 shoulder
arthroplasty procedures over a 5 year period between 2008 and 2012.
They provide short term data (up to 5 years postoperatively) which are not of significant value because at least a 10 year followup is required to prove the superiority of one implant over the other. However it is demonstrated that even in the short term (up to 5 years followup) the hemi-arthroplasty outperforms the resurfacing because of lower rates of revision. Younger patients have higher chances of revision of the hemi resurfacing as compared to hemi-arthroplasty. As stated in the report which is available by the University of Adelaide :
"Hemi resurfacing has a lower rate of
revision in the first 1.5 years, however after 2.5 years
the revision rate was higher than stemmed hemi
arthroplasty."
