Advertisement for orthosearch.org.uk
Results 1 - 6 of 6
Results per page:
Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_9 | Pages 16 - 16
1 Jun 2021
Roche C Simmons C Polakovic S Schoch B Parsons M Aibinder W Watling J Ko J Gobbato B Throckmorton T Routman H
Full Access

Introduction

Clinical decision support tools are software that match the input characteristics of an individual patient to an established knowledge base to create patient-specific assessments that support and better inform individualized healthcare decisions. Clinical decision support tools can facilitate better evidence-based care and offer the potential for improved treatment quality and selection, shared decision making, while also standardizing patient expectations.

Methods

Predict+ is a novel, clinical decision support tool that leverages clinical data from the Exactech Equinoxe shoulder clinical outcomes database, which is composed of >11,000 shoulder arthroplasty patients using one specific implant type from more than 30 different clinical sites using standardized forms. Predict+ utilizes multiple coordinated and locked supervised machine learning algorithms to make patient-specific predictions of 7 outcome measures at multiple postoperative timepoints (from 3 months to 7 years after surgery) using as few as 19 preoperative inputs. Predict+ algorithms predictive accuracy for the 7 clinical outcome measures for each of aTSA and rTSA were quantified using the mean absolute error and the area under the receiver operating curve (AUROC).


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_8 | Pages 12 - 12
1 May 2019
Throckmorton T
Full Access

Reverse total shoulder arthroplasty (RTSA) has a proven track record as an effective treatment for a variety of rotator cuff deficient conditions. However, glenoid erosion associated with the arthritic component of these conditions can present a challenge for the shoulder arthroplasty surgeon. Options for treatment of glenoid wear include partial reaming with incomplete baseplate seating, bony augmentation using structural or impaction grafting techniques, and augmented baseplates. Augmented components have the advantage of accommodating glenoid deformity with a durable material and also ream less subchondral bone; both of which may offer an advantage over traditional bone grafting.

Biomechanical and early clinical studies of augmented glenoid baseplates suggest they are a reasonable treatment option, though posteriorly augmented baseplates have shown better performance than superiorly augmented implants. However, there are no mid- or late-term studies comparing augmented baseplates to bone grafting or partial reaming.

We present a live surgical demonstration of RTSA for a patient with advanced glenoid erosion being treated with an augmented glenoid baseplate that can be dialed in the direction of any deformity (superior, posterior, etc.). This versatility allows the surgeon to place the augment in any direction and is not confined to the traditional concepts of glenoid wear in a single vector. Clearly, longer term follow up studies are needed to determine the ultimate effectiveness of these devices in treating glenoid deformity in RTSA.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 607 - 607
1 Dec 2013
Haider H Sperling J Throckmorton T
Full Access

As reverse total shoulder arthroplasty (RTSA) systems expand with longer durations in vivo, so does the concern and potential complications of wear, debris and osteolysis. Despite some other profound attempts, no wear testing method has stood out to compare implants across systems and labs. The main reasons may have been the diverse sources of forces and motions used in testing, widely different wear amounts which resulted and the general lack of dedicated shoulder simulators. To add a dedicated shoulder simulator to hip and knee simulators would burden the resources of any testing lab. In this study we propose a shoulder wear test method which addresses the above.

Harnessing the wealth of force-motion data from telemetrized shoulder implants from the Bergman's group in Berlin, we synthesized their results to devise a wholistic multi-axes simulation regime for reverse shoulders. The alignment and motions of the humeral cup and the glenosphere were kept anatomically correct (relative to each other) and yielded a physiologically realistic wear-inducing articulation. However, we opted for a very unusual installation/orientation of the whole implant system to allow a twelve station AMTI (hip) simulator to be adapted for this study. The shoulder constructs were aligned with novel fixtures such that the machine's vertical compressive force mimicked the average forces of the shoulder found from the in vivo telemetry data in magnitude and nominal direction. Aligned thus, a patient with a shoulder installed would neither stand, nor lie down, but be oriented in a composite angle relative the simulator original axes. Each anatomic shoulder motion would be achieved by unique computed combinations of the three simulator motion actuators, none of which would be aligned anatomically for the shoulder on its own.

The maximum ranges of cyclic shoulder motion achieved with the constraints of the simulator were 38°–79° of forward elevation repeated in two separate (15°and 45°) elevation planes. The change of elevation plane inherently involved abduction-adduction motion, and simultaneously also involved variation of internal-external rotation within a 57° range. Each elevation rise (twice per cycle) was also accompanied by a sinusoidally rising and falling compressive load in the range 50N–1700N.

The test method was tested (!) by simulating for 2.5 million of the above (double-elevation) cycles and gravimetrically measuring wear of twelve 36 mm size RTSA systems. We compared six systems having vitamin E-infused highly cross-linked polyethylene bearings (100 kGy radiation) to six controls with a medium cross-linked polyethylene of half the radiation dose. Significant wear resulted for the control bearing material (average 17.9 ± 0.851 mg/MC) which was no less than many hips and knees. Multiply (and statistically significantly, p < 0.001) less average wear (3.42 ± 0.22 mg/MC) resulted for the highly cross linked bearings.

The above demonstrated the effectiveness of the test method. Significant wear resulted under physiologically realistic cyclic motion and forces with strong discrimination between two systems whose bearing materials were known to be different in resilience to wear. Using novel fixtures and unusual orientation to utilize a standard commercially available joint simulator promises efficacy of the test method and utility across different labs.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_III | Pages 258 - 258
1 Jul 2011
Zarkadas P Throckmorton T Dahm D Sperling J Cofield R
Full Access

Purpose: The indication to perform a total shoulder arthroplasty (TSA) versus a hemiarthroplasty is guided by a patient’s intended level of activity after surgery. It is unclear what activities patients actually perform following shoulder replacement, therefore, the purpose of this study was to compare the self-reported activities of patients following either a TSA or hemiarthroplasty.

Method: Two groups of 75 patients each, following TSA or hemiarthroplasty, were matched for a variety of demographic variables. A mailed activity questionnaire asked patients to report their level of pain, motion, strength, and a choice of 70 different activities. Reported activities were classified as high (i.e. tennis) or low (i.e. fishing) demand, and categorized as household (i.e. cooking), yard work (i.e. gardening), sporting (i.e. golf), or musical (i.e. piano).

Results: Ninety-six (64%) patients completed the survey, 50 in the TSA group (27F:19M, avg. 53.2 yrs), and 46 in the HA group (29F:21M, avg. 53.5 yrs). Pain was not different between groups (3.6/10 TSA: 3.9/10 HA), yet a significant difference was reported in forward flexion (145° TSA: 120° HA, P< .002) and strength (6.3/10 TSA: 5.3/10 HA, P< .01). Across all categories whether it be high or low demand, the TSA group (10.4 activities/person) reported more activities compared with the hemiarthroplasty group (8.6 activities/person).

Conclusion: The conventional understanding that a hemiarthroplasty provides the possibility for more activity following surgery is not supported by our data. Patients following a TSA reported better motion and strength and were more active than the hemiarthroplasty group.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_III | Pages 270 - 270
1 Jul 2011
Zarkadas P Cass B Throckmorton T Adams R Sanchez-Sotelo J Morrey BF
Full Access

Purpose: Resection elbow arthroplasty is a salvage procedure typically considered as a last resort when other reconstructive options have failed. It was the intent of this study to evaluate the long-term outcome of patients following resection elbow arthroplasty.

Method: Fifty-four elbow resections performed between 1975 and 2005 were retrospectively reviewed. Pre and post-operative elbow function was evaluated with the Mayo Elbow Performance Score (MEPS) and additional follow-up data was compiled using the Disability of Shoulder and Hand (DASH) score. All patients in this study had a resection following a failed total elbow arthroplasty (TEA). Nineteen patients had died at time of follow-up, and 5 patients were lost to follow-up, leaving 30 of the surviving 34 patients (88%) available for long-term evaluation.

Results: The main indication for resection in this study was infection (50 of 54 elbows). The average MEPS prior to resection was 36. The long-term results in 30 patients at an average of 11 yrs (range 2.7–28 yrs) demonstrated an average MEPS score of 60, and a DASH score of 71. Complications were common including persistent infection requiring re-operation (44%), intra-operative fracture (32%), transient (11%) or permanent (5.5%) nerve damage, and one case of vascular injury requiring amputation. Achieving a stable resected elbow correlated strongly with a good long-term MEPS score (r=0.75).

Conclusion: This study emphasizes the difficulty in treating patients with a failed total elbow arthroplasty. Resection arthroplasty is a salvage procedure indicated primarily for persistently infected TEA and results in satisfactory outcomes in this population.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 491 - 491
1 Apr 2004
Spengler D Throckmorton T
Full Access

Introduction This review evaluates the clinical outcomes and complications of lumbar spinal fusion procedures for patients with a variety of degenerative disorders.

Methods Patients were evaluated with respect to outcome and complications. Further analysis allowed us to compare results in patients who had spinal instrumentation versus in situ fusion. In addition, our patients who underwent primary lumbar fusion were compared with those who underwent revision surgery. One author performed 148 spinal fusion procedures for degenerative disorders between 1990 and 1995. Outcomes were classified using Odom’s Criteria by the co-author. Patients were analyzed in groups so that we could compare primary versus revision procedures and instrumented versus non-instrumented fusions. The 148 patients ranged in age from 22 to 88, with 86 being female. Diagnostic categories included: instability (3%), stenosis (47%), spondylolisthesis (34%), disc herniation (10%), degenerative scoliosis (9%), and spondylosis (4%). Eighty-one patients had primary procedures; 104 patients were instrumented with pedicle screw systems, 127 patients (86%) were fused using iliac crest autograft.

Results Fifteen percent of primary patients developed complications compared to 24% of revision patients. Twenty-one percent of instrumented patients developed complications compared to 16% of non-instrumented patients. Transition syndrome developed in 13% of patients following spinal instrumentation. Average follow-up was 49.5 months. Seventy percent of primary patients had good/excellent results compared with 69% for the revision patients. Seventy-two percent of instrumented patients had good/excellent results compared to 65% of non-instrumented patients.

Conclusions Our retrospective review suggests that well selected revision surgery patients can have similar outcomes to patients who undergo initial lumbar fusion procedures. Although complications occur more frequently in patients who have revision fusions and/or instrumented fusions, clinical outcomes are similar.