The effect of epidemiologic and intraoperative factors on survival of the standard Souter-Strathclyde total elbow arthroplasty

Prognostic factors associated with failure of total elbow arthroplasty

Aims

The aims of this study were to identify and evaluate the current literature examining the prognostic factors which are associated with failure of total elbow arthroplasty (TEA).

Methods

Electronic literature searches were conducted using MEDLINE, Embase, PubMed, and Cochrane. All studies reporting prognostic estimates for factors associated with the revision of a primary TEA were included. The risk of bias was assessed using the Quality In Prognosis Studies (QUIPS) tool, and the quality of evidence was assessed using the modified Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework. Due to low quality of the evidence and the heterogeneous nature of the studies, a narrative synthesis was used.

Results

A total of 19 studies met the inclusion criteria, investigating 28 possible prognostic factors. Most QUIPS domains (84%) were rated as moderate to high risk of bias. The quality of the evidence was low or very low for all prognostic factors. In low-quality evidence, prognostic factors with consistent associations with failure of TEA in more than one study were: the sequelae of trauma leading to TEA, either independently or combined with acute trauma, and male sex. Several other studies investigating sex reported no association. The evidence for other factors was of very low quality and mostly involved exploratory studies.

Conclusion

The current evidence investigating the prognostic factors associated with failure of TEA is of low or very low quality, and studies generally have a moderate to high risk of bias. Prognostic factors are subject to uncertainty, should be interpreted with caution, and are of little clinical value. Higher-quality evidence is required to determine robust prognostic factors for failure of TEA.

What design and material factors impact the wear and corrosion performance in total elbow arthroplasties?

The survivorship of total elbow arthroplasties is lower than surgeons and patients would like it to be, especially in patients with posttraumatic arthritis of the elbow. To improve durability, it is important to understand the failure modes of existing implants. Total elbow arthroplasties were designed primarily for low-demand rheumatoid patients. As surgical indications have extended to more active patient populations, the mechanical performance of current designs must meet an increased mechanical burden. Evaluating the degree to which they do this will guide conclusions about which contemporary devices might still meet the need and, as importantly, what design and material changes might be needed to improve performance. WHERE ARE WE NOW?: The reasons for failures of total elbow arthroplasties include infection, loosening, polyethylene wear, locking mechanism failure, periprosthetic fracture, implant fracture, and instability. Implant design factors that have influenced wear include implant constraint, material, coatings, and metal backing. Surgical factors associated with increased wear and subsequent total elbow arthroplasty failure include soft tissue balancing and restoration of alignment and implant positioning. WHERE DO WE NEED TO GO?: A clear need exists for improving the performance of total elbow arthroplasty. Many of the failures that have limited the survivorship of elbow arthroplasties thus far are mechanical in nature with wear-related problems a dominating influence. Much of what we know about the results of total elbow arthroplasty is from small studies frequently involving the designer of the implant. The establishment of total elbow arthroplasty registries coupled with the increasing regulatory burden of postmarket surveillance would lead to a better understanding of the complications and survivorship of elbow arthroplasties. Another primary goal must be to achieve a better understanding of the biomechanics of the normal elbow and how the mechanics are altered after the insertion of elbow arthroplasty components. HOW DO WE GET THERE?: Improving the performance and survivorship of total elbow arthroplasty will require the integration of clinical and implant performance data gained through the establishment of registries with a concerted basic science effort to better understand the functional loads across the joint and to incorporate these loads into experimental and computational models to allow assessment of design and material changes intended to improve durability.

Short-term results of the PROSNAP linked elbow prosthesis with a snap-in structure and modular flange for the reconstruction of severely damaged rheumatoid elbows

BACKGROUND

We aimed to evaluate the early clinical results of the reconstruction of problematic elbow joints due to rheumatoid arthritis (RA) using a PROSNAP linked elbow prosthesis (Kyocera Medical, Osaka, Japan) for total elbow arthroplasty.

METHODS

Seventeen elbows in 14 RA patients were replaced with a PROSNAP elbow with cement fixation. The patients comprised 1 man and 13 women, with a mean age of 63.9 years (range, 52-83 years) at the time of surgery. The preoperative conditions of the elbows were arthritis mutilans (n = 10), an ankylosed or stiff elbow with a preoperative range of motion of 45° or less (n = 4), and loosening of a primary total elbow arthroplasty (n = 3). The mean follow-up period was 47.7 months (range, 32-69 months), with a 100% follow-up rate. The clinical outcome of the elbows was evaluated by the Mayo Elbow Performance Index (maximum, 100 points).

RESULTS

The mean postoperative Mayo Elbow Performance Index score improved from 57.6 points to 97.1 points. Preoperatively, 3 of the 17 elbows were judged as good, 7 as fair, and 7 as poor; at final follow-up, 16 elbows were judged as excellent and 1 as good. Complications were noted in 1 elbow (6%), which had undergone a postoperative fracture.

CONCLUSIONS

The PROSNAP elbow prosthesis can be safely implanted through a relatively easy procedure and provides satisfactory short-term clinical outcomes for the reconstruction of severely damaged RA elbows.

LEVEL OF EVIDENCE

Level IV, case series, treatment study.

Aseptic loosening rate of the humeral stem in the Coonrad-Morrey total elbow arthroplasty. Does size matter?

BACKGROUND

Aseptic implant loosening is one of the most common complications leading to revision surgery in total elbow arthroplasty. Different humeral stem lengths are available with varying designs. In general, the decision of which stem length to use depends on the surgical diagnosis or simply the surgeon preference. Often, the longer stem is used for post-traumatic or revision cases while for rheumatoid patients the shorter stem is preferred. There are no data in the literature to favor one humeral stem size over the other according to the diagnosis.

METHODS

We analyzed the total elbow joint database of the Coonrad-Morrey design at our institution for aseptic loosening leading to revision and compared the revision rate and the survival of the 4- and 6-inch humeral stems.

RESULTS

Overall, revision for aseptic humeral loosening is infrequent and occurred in only 16 of 711 total elbow arthroplasties during a mean follow-up of 88 months. There was no significant difference in the revision rate between the 2 stem lengths (1.9% for the 4-inch stems and 2.6% for the 6-inch stem).

CONCLUSION

Revision rate was correlated to the surgical diagnosis and was significantly higher for post-traumatic patients than for rheumatoid patients (5.1% vs 0.66%, P < .001). Of interest, and possibly not surprising, the mean time to revision was shorter for the 4-inch stems than it was for the 6-inch stems (37 vs 95 months, P = .034).

Modes of wear after semiconstrained total elbow arthroplasty

BACKGROUND

Osteolysis and aseptic loosening are increasingly recognized complications of total elbow arthroplasty. However, unlike the literature on total hip and knee arthroplasty, studies describing the mechanisms of these processes after total elbow arthroplasty are sparse.

METHODS

Semiconstrained total elbow arthroplasty components were retrieved from sixteen elbows (fourteen patients) at either revision surgery (at a mean of five years after implantation) for mechanical failure (fifteen elbows) or postmortem examination (one elbow). In all cases, the retrieved implant was the primary implant. The patterns of damage on these components were investigated with stereomicroscopy in correlation with clinical findings, serial radiographs, and histopathological observations.

RESULTS

All of the retrieved devices exhibited multiple modes of wear. Damage to the humeral and ulnar polyethylene bushings was nearly universal; twenty-seven of twenty-eight humeral bushings demonstrated asymmetrical thinning, while fifteen of sixteen ulnar bushings demonstrated elliptical plastic deformation. In addition, unintended metal-on-metal wear between bearing and nonbearing surfaces or between two nonbearing surfaces was commonly observed, typically in association with wear and deformation of the polyethylene bushings. Wear between the stem and the cement mantle was observed in most of the ulnar components. The histopathology of the periprosthetic tissues was similar in character to that observed in association with osteolysis and loosening of total hip and knee replacements, while analysis of the particulate debris revealed a preponderance of titanium alloy and polyethylene debris. Barium sulfate particles were also observed to a lesser extent.

CONCLUSIONS

Multimodal wear in total elbow replacements can lead to osteolysis, aseptic loosening, and prosthetic and periprosthetic fracture necessitating revision surgery. Polyethylene wear and damage, as well as unintended metal-on-metal wear, contribute to the periprosthetic particulate burden, which is likely pathogenic in these processes.

The results of arthroplasty in osteoarthritis of the shoulder

We have undertaken a prospective clinical and radiological analysis of 124 shoulder arthroplasties (113 patients) carried out for osteoarthritis. The clinical results showed improvement in the absolute Constant score and the American Shoulder and Elbow Surgeons score of 22 and 43, respectively. Both were statistically significant (p < 0.001). There was no significant difference in the scores after hemiarthroplasty and total arthroplasty in those patients with an intact rotator cuff. When revision was used as the end-point for survival at ten years, survival of 86%, or 90% if glenoid components made of Hylamer sterilised in air were omitted, was obtained in primary osteoarthritis. The most common cause for revision in the hemiarthroplasty group was glenoid pain at a mean of 1.5 years; in the total arthroplasty group it was loosening of the glenoid at a mean of 4.5 years. Analysis of pre-operative factors showed that the risk of gross loosening of the glenoid increased threefold when there was evidence of erosion of the glenoid at operation. Shoulder arthroplasty should not be delayed once symptomatic osteoarthritis has been established and should be undertaken before failure of the cuff or erosion of the glenoid are present.

Comparison of survivorship between standard and long-stem souter-strathclyde total elbow arthroplasty

This study compared 107 cases of rheumatoid arthritis that had the long-stem humeral component of the Souter-Strathclyde total elbow arthroplasty introduced as a primary procedure with a similar group of 202 cases that had the standard component. Both groups were comparable with regard to age range and sex ratio. Follow-up of the longer-stem component was somewhat shorter, being a mean of 4.4 years as opposed to 9.3 years. Kaplan-Meier survival analyses were undertaken for both revision and radiologic loosening of components as terminal events. There was no significant difference between the cumulative survival of the standard and long-stem humeral implants when revision was the endpoint. Although survival of both implants was similar, the reasons for this were different. More specifically, for the standard humeral component, 25 out of 32 revisions were for humeral loosening. For the long stem, however, 5 out of a total of 7 revisions were due to instability; no long-stem humeral component had been revised for loosening. In addition, linking the components by way of a snap-fit component was associated with a higher rate of loosening; more specifically, 5 out of 16 cases were revised. As a result of this study, we recommend the use of a long-stem Souter-Strathclyde humeral component as a primary implant. Other crucial components for long-stem survival, however, are surgical technique and alignment of the implant.