Impact of Comorbidities and Previous Surgery on Mid-Term Results of Revision Total Knee Arthroplasty for Periprosthetic Joint Infection

(1) Background: In the treatment of periprosthetic joint infection (PJI), the individual host status and previous surgical procedures appear to have a relevant influence on success rates and clinical outcome of knee revision surgery. Current data about the predictive value are limited in this subgroup of patients. (2) Methods: Retrospectively, 107 patients (109 knees) undergoing two-stage exchange knee arthroplasty for PJI using a rotating-hinge design with at least two years follow-up. The cumulative incidence (CI) for different endpoints was estimated with death as competing risk. Univariate and multivariate analyses for potential predictive factors were performed. Patient-related outcome measures (PROMs) for clinical outcome were evaluated. (3) Results: At 8 years, the CI of any revision was 29.6%, and of any reoperation was 38.9%. Significant predictors for risk of re-revision were the Charlson Comorbidity Index (CCI) and the number of previous surgical procedures prior to explanation of the infected implant. The functional and clinical outcome demonstrated acceptable results in the present cohort with a high comorbidity level. (4) Conclusions: A compromised host status and multiple previous surgical procedures were identified as negative predictors for re-revision knee surgery in the treatment of PJI. Reinfection remained the major reason for re-revision. Overall mortality was high.

Mid-term results of complex primary total knee arthroplasty using a rotating-hinge implant

BACKGROUND

The indications and outcomes of semi- or fully-constrained knee implants in primary total knee arthroplasty (TKA) are still controversially discussed. The present study aims to evaluate the mid-term results and complications of a modular/non-modular rotating-hinge implant in complex primary TKA.

METHODS

Eighty-two patients (86 knees) following primary TKA were retrospectively evaluated with a mean follow-up of 63 months. The functional outcome was assessed using the American Knee Society Score (AKSS) and the Oxford Knee Score (OKS). A Visual Analog Scale (VAS) was used to determine pain levels. Implant survival and reoperation rateswere estimated using competing risk analysis. Cox regression analysis wasperformed to evaluate the influence of modularity on implant survival.

RESULTS

The survival rate with the endpoint implant revision was 90% (95 %CI:83-98%) and the survival rate with the endpoint all reoperations was 84% (95 %CI:75-94%) at 7 years. The AKSS improved significantly from 24 (SD 14.9, range:0-69) preoperatively to 83 (SD 14.3, range:57-100) postoperatively (p < 0.001); functional AKSS improved significantly from 27 (SD 24.3, range:0-100) to 46 (SD: 32.9, range 0-100) (p = 0.003), and OKS from 19 (SD: 8.3, range:5-43) to 29 (SD: 10.7, range:6-48), respectively (p < 0.0001). VAS decreased significantly from 8 (SD: 2.6, range:0-10) preoperatively to 3 (SD: 2.9, range:0-9) postoperatively (p < 0.0001). There was no significant influence of modularity on revision rates comparing modular to non-modular implants (p = 0.072).

CONCLUSIONS

The present rotating-hinge implant provides substantial improvement in function and reduction of pain with good implant survival in the mid-term. Modularity was not associated with higher rates of revision.

Variation of the glenohumeral and scapulothoracic motion in progressive severity of glenohumeral osteoarthritis

INTRODUCTION

The aim of this study is to investigate the variation of the glenohumeral and scapulothoracic motion in progressive severity of glenohumeral osteoarthritis using a 3-D-motion analysis. Moreover, the variation of the Constant Score is evaluated.

HYPOTHESIS

The hypothesis is that the motion of the scapulothoracic joint may partly compensate for the loss of the glenohumeral joint movement in patients with increasing severity of glenohumeral osteoarthritis.

MATERIAL AND METHODS

A total of 21 patients with primary osteoarthritis of the glenohumeral joint were clinically examined, divided in three groups (SP1-SP3) according to size of their caudal osteophyte. The contribution of the scapulothoracic (acromioclavicular and sternoclavicular) joint to the total arm (humerothoracical) elevation in sagittal and frontal plane was measured with 3D motion analysis and the Constant Score was evaluated.

DISCUSSION

In sagittal plane elevation (anteversion) the contribution of the scapulothoracic joint to the total elevation was while arm raising 32.7% (SD 8.0%) in Group SP1, 36.6% (SD 11.0%) in Group SP2 and 49.6% (SD 9.0%) in Group SP3 (p=0.002). The contribution of the scapulothoracic joint to the total elevation while arm lowering was 31.4% (SD 9.0%) in Group SP1, 39.0% (SD 13.0%) in Group SP2 and 49.7% (SD 12.0%) in Group SP3 (p=0.043). In frontal plane elevation (abduction) the contribution of the scapulothoracic joint was while arm raising 33.7% (SD 8.0%) in Group SP1, 34.0% (SD 10.0%) in Group SP2 and 42.3% (SD 9.0%) in Group SP3 (p=0.071). While arm lowering the contribution of the scapulothoracic joint was 30.8% (SD 10.0%) in Group SP1, 36.3% (SD 12.0%) in Group SP2 and 44.8% (SD 8.0%) in Group SP3 (p=0.022). The group SP1 achieved a Constant Score of 78.00 (SD 9.823) points. The group SP2 achieved a Constant Score of 53.57 (SD 13.92) and the group SP3 38.64 (SD 10.40). There is a significant difference between the three groups (p<0.001). Increasing severity of glenohumeral osteoarthritis leads to a reduced motion of the glenohumeral joint. Instead the magnitude of the scapulothoracic motion increases.

LEVEL OF PROOF

V, Case Series.

Comparison of glenohumeral and humerothoracical range of motion in healthy controls, osteoarthritic patients and patients after total shoulder arthroplasty performing different activities of daily living

PURPOSE

The purpose of this study was to examine how total shoulder arthroplasty improves performance of activities of daily living compared to patients with glenohumeral osteoarthritis and how they perform compared to healthy controls.

METHODS

Glenohumeral and humerothoracical elevation used by patients with primary osteoarthritis (12 participants, 16 shoulders), after total shoulder arthroplasty (16 participants, 24 shoulders) and healthy controls (11 participants, 22 shoulders) for four different activities of daily living were assessed using 3D motion analysis. Analysis of range of motion and angle time series was performed.

RESULTS

Range of motion used for activities of daily living was better in patients treated with anatomical total shoulder arthroplasty than in patients with primary glenohumeral osteoarthritis. Although it was still reduced compared to healthy individuals. Angle time series showed improved kinematics in patients with total shoulder arthroplasty compared to patients with glenohumeral osteoarthritis. Both glenohumeral and humerothoracical elevation kinematic time series were in almost all cases in between the control group's and the osteoarthritis group's.

CONCLUSION

Total shoulder arthroplasty improves performance of activities of daily living in patients with primary glenohumeral osteoarthritis but cannot restore the full range of Motion compared to healthy controls. A prospective study with pre- and postoperative examinations is necessary to understand to understand how preoperative status influences the postoperative results.

Functional midterm follow-up comparison of stemless total shoulder prostheses versus conventional stemmed anatomic shoulder prostheses using a 3D-motion-analysis

Background

The aim of this study is to compare the functional midterm outcome of stemless shoulder prostheses with standard anatomical stemmed shoulder prostheses and to show that the STEMLESS results are comparable to the STEMMED with respect to active maximum range of shoulder motion (ROM) and Constant score (CS).

Methods

Seventeen patients underwent total shoulder arthroplasty (TSA) in 25 shoulder joints. Stemless TSA was performed in 12 shoulder joints (group STEMLESS), third-generation stemmed TSA in 13 shoulder joints (group STEMMED). Functional results were documented using the CS. 3D-motion-analysis using the Heidelberg upper extremity model (HUX) was conducted to measure active maximum (ROM).

Results

The group STEMLESS achieved a CS of 67.9 (SD 12.0) points and the group STEMMED of 70.2 (SD 5.8 points) without significant difference between the groups (p = 0.925). The maximum ROM of the group STEMLESS, ascertained by 3-D-motion-analysis, was in forward flexion 125.5° (SD 17.2°), in extension 49.4° (SD 13.8°), in abduction 126.2° (SD 28.5°) and in external rotation 40.3° (SD 13.9°). The maximum ROM of the group STEMMED, also ascertained by 3-D-motion analysis, was in forward flexion 135.0° (SD 16.8°), in extension 47.2° (SD 11.5°), in abduction 136.3° (SD 24.2°) and in external rotation 40.1° (SD 12.2°). The maximum ROM of the STEMLESS group was lower in forward flexion and abduction, higher in extension and almost identical in external rotation. But there was no significant difference (forward flexion p = 0.174, extension p = 0.470, abduction p = 0.345, external rotation p = 0.978).

Conclusion

Both types of shoulder prostheses achieve a similar and good active ROM and similar results in CS.

Trial registration

DRKS00013166, retrospectively registered, 11.10.2017