INTRODUCTION

Early discharge after total joint arthroplasty has started to gain acceptance in select academic centers. The purpose of this study was to compare the risk of readmission of Medicare patients discharged one day after total knee arthroplasty (TKA), versus those discharged two or three days after surgery. Our hypothesis was that patients with length of stay (LOS) of one day would not have a higher risk of readmission in a community setting.

Introduction

Rapid recovery protocols after joint replacement have been implemented widely to decrease hospital length of stay (LOS). Minimally-invasive total knee arthroplasty (MIS-TKA) may facilitate rapid recovery for patients. Increased complications and LOS have been documented in morbidly obese TKA patients. The objective of the current study was to retrospectively evaluate the impact of morbid obesity on MIS-TKA patients.

Introduction

Liposomal bupivacaine has been shown to be effective in managing post-operative pain in hallux valgus and hemorrhoid surgery. However, non-industry-supported and well-powered randomized studies evaluating its efficacy in Total Knee Arthroplasty (TKA) are lacking. Our hypothesis was that liposomal bupivacaine would not decrease post-operative visual analog pain scores (VAS) or narcotic consumption in the acute post-operative period.

Soft tissue Intravenous drug abuse is known to be associated with significant health problems including soft tissue infections. Our department observed a concerning increase in the level of admissions of drug users presenting with severe soft tissue infections after injecting “Legal Highs”. These findings contributed to the body of evidence which led to the introduction of a Temporary Banning Order on these agents in Scotland in April 2015. The aim of this study was to investigate the effectiveness of banning orders on reducing patients presenting with soft tissue infections associated with intravenous drug abuse.

All admissions to the Orthopaedic trauma unit with soft tissue infections over three six-month periods in 2013, 2014 and 2015 were investigated. Those associated with intravenous drug usage were identified. Cases were reviewed to assess patient demographics, co-morbidities, infection characteristics and management.

There was a three-fold increase in hospital admissions for soft tissue infections resulting from intravenous drug use between 2013 and 2014. In 2013, 9.1% of admissions were related to use of “Legal Highs”, whilst in 2014 this had increased to 68.8%. After April 2015 there was a 28% reduction in admissions of intravenous drug use related soft tissue infections with “Legal High” associated admissions reduced to 39%.

“Legal Highs” were responsible for the dramatic increase in admissions associated with soft tissue infections resulting from intravenous drug abuse seen between 2013 and 2014. Introduction of Temporary Banning Orders for “Legal Highs” in April 2015 has been instrumental in reducing these admissions.

Introduction

Rapid recovery protocols (RRP) for joint replacements have been shown to improve efficiency, reduce costs, and minimize adverse outcomes in academic health systems. The purpose of this study is to evaluate if RRP can be safely implemented in a community health system for total knee arthroplasty.

The primary aim of this study was to identify risk factors for developing neuritis and its impact on outcome following open reduction internal fixation (ORIF) of distal humerus fractures.

Patients were identified from a prospective trauma database (1995–2010). All fractures of the distal humerus (OA-OTA Type A, B, C) managed with ORIF were included. Prospective long-term follow up was collected by telephone. Demographic data, fracture classification, intraoperative details (time to surgery, tourniquet, approach, fixation technique, nerve transposition), subsequent surgeries, presence of postoperative nerve palsy, complications and range of motion were collected. The Broberg and Morrey Elbow Score and DASH score were used as functional outcome measures.

Eighty-two patients, mean age 50(range, 13–93) were included. 16% (13/82) developed post-operative ulnar neuritis, 7% (6/82) radial neuritis and 5% (4/82) longterm nonspecific dysaesthesia. Short-term (mean 10 months, range 1–120, collected in 82 patients) and long-term (mean 6 years, range 4–18, collected in 45%, 34/75, of living patients) was completed. In patients with nerve complication: average Broberg and Morrey score was 86 (76% good/excellent), average DASH was 24.7(range, 3.3–100) and Oxford Elbow Score was 39.5(range, 18–48). Compared to: 94 (96% good/excellent), 17.7(range, 0–73.3) and 43.8(range, 17–48) in patients without. Mean pain score was 3.7 in patients with nerve complication compared to 2 without. Nerve complications were seen with increased frequency in young, male patients with high energy and Type C injuries.

Nerve complication following ORIF of distal humerus fractures is relatively common. They have detrimental impact on functional outcome. Certain groups appear to be at increased risk.

Introduction: In the past, displaced radial neck fractures have been treated either by excision, prosthetic replacement or internal fixation with a plate and screws. More recent studies have investigated less invasive fixation constructs using two crossed obliquely orientated screws within the radial neck. A new ‘tripod’ technique using three crossed screws has been proposed and was tested to evaluate whether it has at least equivalent stiffness and strength to fixation with a T-plate.

Methods: Twenty composite sawbones with an axially stable simulated radial neck fracture were fixed either with the tripod technique (three crossed 2.3mm screws) or with a 2.3mm T-plate. The specimens were tested for stiffness at 10 N load in three directions (anteroposterior (AP), ulnar-radial (UR) and eccentric axial (EA)) and load to yield and ultimate failure. The modes of failure of fixation were also evaluated.

Results: The tripod had significantly higher stiffness than the T-plate in AP loading (168 N/mm vs 95 N/mm, p=0.006) and trended to superior stiffness in UR loading (121 N/mm vs 77 N/mm, p=0.06). Both constructs were highly stiff in EA compression (513 N/mm vs 638 N/mm). The strength to yield and failure was significantly higher for the tripod in both AP loading (yield: 432 N vs 36 N, failure: 467 N vs 143 N, p< 0.001) and UR loading (yield: 444 N vs 36N, failure: 444N vs 76 N, p< 0.001). The T-plates failed by screw cut-out and subsequent plastic deformation of the plate. The tripod constructs did not fail at the load required to cause brittle fracture in the sawbone specimen, remote to the site of fixation.

Conclusions: The tripod technique is a biomechanically sound construct for the fixation of axially stable radial neck fractures and thus further clinical research to evaluate the clinical application of this technique is justified.

A new ‘tripod’ technique using three crossed screws to stabilise radial neck fractures has been proposed and this technique was tested in vitro to evaluate whether it has at least equivalent stiffness and strength to fixation using a T-plate.

Twenty composite sawbones with an axially stable simulated radial neck fracture were fixed either using the tripod technique (three crossed 2.3mm screws) or with a 2.3mm T-plate and screws. The specimens were tested for stiffness at 10 N load in three directions (antero-posterior (AP), ulnar-radial (UR) and eccentric axial (EA)) and load to yield and ultimate failure. The modes of failure of fixation were also evaluated.

The tripod had significantly higher stiffness than the T-plate in AP loading (168 N/mm vs 95 N/mm, p=0.006) and trended to superior stiffness in UR loading (121 N/mm vs 77 N/mm, p=0.06). Both constructs were highly stiff in EA loading (513 N/mm vs 638 N/mm). The strength to yield and failure was significantly higher for the tripod in both AP loading (yield: 432 N vs 36 N, failure: 467 N vs 143 N, p< 0.001) and UR loading (yield: 444 N vs 36N, failure: 444N vs 76 N, p< 0.001). The T-plates failed by screw cut-out and subsequent plastic deformation of the plate. The tripod constructs did not fail at the load required to cause brittle fracture in the sawbone specimen, remote to the site of fixation.

The tripod technique is a biomechanically sound construct for the fixation of axially stable radial neck fractures and thus further research to evaluate the clinical results of this technique is justified.

The purpose of this study was to evaluate trabecular bone response, at fifty-two week follow-up, to four different synthetic graft materials (CaSO4 and CaSO4 – HA/TCP composites) as compared to autograft in a canine defect model. The group with the highest HA/ TCP proportion had the greatest amount of residual graft material and total mineralized material. Increasing the proportion of HA/TCP reduces the rate of dissolution, and appears to have little effect on bone formation at long term follow-up. This study further suggests that a range of composites could be created to match the spectrum of resorption rates demanded by clinical applications.

The purpose of this study was to evaluate trabecular bone response to four synthetic graft materials (CaSO4 and CaSO4 – HA/TCP composites) as compared to autograft in a canine defect model, at long term follow-up.

Both 85% CaSO4 – 15% HA/TCP and 65% CaSO4 – 15% HA/TCP showed bone formation similar to autograft. The group with the highest proportion of HA/TCP lasted longer than the other formulations. The results suggest that increased HA/TCP proportions reduce the rates of dissolution, without compromising bone formation in the current model.

Results suggests that a range of composites could be created to match the spectrum of resorption rates demanded by clinical applications.

In this REB-approved RCT, bilateral humeral and femoral cylindrical defects were filled with one of four types of pellets with varying proportions of CaSO4 – HA/TCP, autograft bone, or left unfilled. After sacrifice at six, twelve, twenty-six or fifty-two weeks, defect sites were evaluated histologically for tissue and inflammatory response, area fractions of residual graft material, and bone ingrowth in the defects.

The area of the defect occupied by residual graft material in the group with the highest percentage of HA/TCP was greater than in other composite groups (p< 0.0001). This group contained the greatest amount of total mineralized material (graft material + bone) (p< 0.03. The extent of new bone formation increased from twelve to twenty-six weeks (p< 0.0001). Both 85% CaSO4 – 15% HA/TCP and 65% CaSO4 – 15% HA/TCP showed bone formation similar to autograft.

Funding: Research grant from Stryker Howmedica, Matwah, NJ.

The purpose of this study was to evaluate trabecular bone response to four different synthetic graft materials (CaSO₄ and CaSO₄ – HA/TCP composites) as compared to autograft in a canine defect model. The group with the highest HA/TCP proportion (and the lowest CaSO4 proportion) had the greatest amount of residual graft material and total mineralized material (p< 0.05). Increasing the proportion of HA/TCP reduces the rate of dissolution, and appears to have little effect on bone formation. This study suggests that a range of composites could be created to match the spectrum of resorption rates demanded by clinical applications.

Calcium sulfates and phosphates have become popular clinically for use as bone graft substitutes, however, their in-vivo performance has not been well characterized. The purpose of this study was to evaluate trabecular bone response to four synthetic graft materials (CaSO₄ and CaSO₄ – HA/TCP composites) as compared to autograft in a canine defect model.

Both 100% CaSO₄ and the 3 CaSO₄– HA/TCP formulations showed good bone formation. The group with the highest proportion of HA/TCP lasted longer than the other formulations, suggesting increased HA/TCP proportions reduce the rates of dissolution, without compromising bone formation in the current model.

Results suggests that a range of composites could be created to match the spectrum of resorption rates demanded by clinical applications.

In this REB-approved RCT, bilateral humeral and femoral cylindrical defects were filled with one of four types of pellets with varying proportions of CaSO₄ – HA/TCP, autograft bone, or left unfilled. After sacrifice at six or twelve weeks, defect sites were evaluated histologically for tissue and inflammatory response, area fractions of residual graft material, and bone ingrowth in the defects.

The area of the defect occupied by residual graft material in the group with the highest percentage of HA/TCP was greater than in other composite groups (p< 0.0006). At twelve weeks, this group contained more total mineralized material (graft material + bone) (p< 0.005). The extent of new bone formation was not different among the composite groups at either time-point, but all showed more bone formation than the empty defect.

Funding: This study was funded by a research grant from Stryker Howmedica, Matwah, NJ.

Introduction and Aims: Calcium sulfates and phosphates have become popular as bone graft substitutes, however, their in-vivo performance has not been well characterised. The purpose of this study was to evaluate trabecular bone response to four synthetic graft materials (CaSO4 and CaSO4 – HA/TCP composites) as compared to autograft in a canine defect model.

Method: In this REB-approved RCT, bilateral humeral and femoral cylindrical defects were filled with one of four types of pellets with varying proportions of CaSO4 – HA/TCP, autograft bone, or left unfilled. After sacrifice at six or 12 weeks, defect sites were evaluated histologically for tissue and inflammatory response, area fractions of residual graft material, and bone ingrowth in the defects.

Results: The area of the defect occupied by residual graft material in the group with the highest percentage of HA/TCP was greater than in other composite groups (p< 0.0006). At 12 weeks, this group contained more total mineralised material (graft material + bone) (p< 0.005). The extent of new bone formation was not different among the composite groups at either time-point, but all showed more bone formation than the empty defect. Both 100% CaSO4 and the 3 CaSO4 – HA/TCP formulations showed good bone formation.

Conclusion: The group with the highest proportion of HA/TCP lasted longest, suggesting increased HA/TCP proportions reduce the rates of dissolution, without compromising bone formation in this model. Results suggest that a range of composites could be created to match the spectrum of resorption rates demanded by clinical applications.