Do TKAs in Patients with Higher BMI Take Longer, and is the Difference Associated with Surgeon Volume? A Large-database Study from a National Arthroplasty Registry.

BACKGROUND: Increased surgical time in TKA may impact economic costs and clinical outcomes. Prior work has found that TKAs in patients with high BMI take longer, and these patients may be at greater risk for postoperative complications like infection. However, these studies included small numbers of patients and surgeons from single institutions and they did not consider surgeon volume. QUESTIONS/PURPOSES: Using the New Zealand Joint Registry (NZJR), we asked: (1) Is there a relationship between increasing patient BMI and TKA operative time? (2) Is the effect of BMI on surgical time less pronounced among surgeons who perform more TKAs per year than those who perform fewer? METHODS: Data were collected from the NZJR between January 2010 and December 2018 as it is the only national registry that records both BMI and surgical time. Primary TKA performed for osteoarthritis by surgeons with more than 50 TKAs over the period of the study were identified. BMI and operative time (skin incision to closure in minutes) were recorded. Patients with the following were excluded: lateral parapatellar or minimally invasive approaches; navigated, patient-specific instrumentation, or robot-assisted TKA; uncemented or hybrid fixation; those with procedures performed by a trainee (all or part); or a nonosteoarthritic indication. Of 64,108 TKAs performed during the study period, a total of 42% (27,057) met our inclusion criteria. The primary outcome was the effect of BMI on operative time. Operative time is expressed in minutes as a mean for each single-unit BMI increase across all surgeons, controlled for other variables that might influence operative time such as patella resurfacing and cruciate-retaining versus posterior-stabilized designs. Overall, the mean operative time (skin incision to closure) was 79 ± 22 minutes. Surgical experience was assessed by subdividing surgeons into six groups according to the number of TKAs performed annually (< 10, 10 to 24, 25 to 49, 50 to 74, 75 to 99, and > 100). Statistical analyses were performed including a general linear model to assess the independent association between BMI and operative time, allowing for the effects of other patient and surgical features. In addition, linear regression analyses explored the associations between BMI and operative time in the whole group and within surgical volume groups. RESULTS: There was an association between increasing BMI and increasing surgical duration. The mean operative time increased from 75 ± 22 minutes in patients with a normal BMI of 25 kg/m2 to 87 ± 24 minutes in patients with a BMI of 40 kg/m2 to 94 ± 28 minutes in patients with a BMI > 50 kg/m2 (p < 0.001). Surgeons performing fewer than 25 TKAs per year took 14% longer to perform a TKA on a patient with a BMI of 40 kg/m2 than on a patient with a normal BMI of 25 kg/m2. However, surgeons performing greater than 25 TKAs per year took 10% longer. CONCLUSION: In this study, an increase BMI was associated with increased surgical time in TKA. Surgical duration for high-volume surgeons appears less influenced by increases in BMI than lower volume surgeons. Although the absolute increase in duration was small, prolonged surgical time may reduce theater productivity. Even though the issues around managing patients with high BMI are multifactorial and complex, considerations from these findings include ensuring appropriate theater scheduling and possibly referring patients with high BMI to specialist centers. Further studies should focus on assessing the effectiveness of such measures in reducing complications and improving outcomes in patients with elevated BMI. LEVEL OF EVIDENCE: Level III, therapeutic study.

Comparable outcomes of in-cement revision and uncemented modular stem revision for Vancouver B2 periprosthetic femoral fracture at 5 years.

INTRODUCTION: Periprosthetic femoral fractures (PFF) are detrimental for patients. Vancouver B2 fractures about a cemented stem can be revised to a longer uncemented stem or using an in-cement revision, if the cement mantle is adequate. There are reports documenting the success of both techniques. The aim of this single centre study was to perform a direct comparison of these two procedures. MATERIALS AND METHODS: A retrospective study of consecutive Vancouver B2 PFFs around a cemented stem during 16 years was performed. All study cases were treated either using an in-cement revision or with an uncemented stem revision. Preoperatively, the groups were compared based upon age, gender, ASA, BMI, and Charlson comorbidity score. The outcome measures were surgical time, complications, in-hospital stay, revisions, 1-year readmission rate, and survivorship. RESULTS: After a median of 3.5 years, there were 70 patients in the uncemented and 31 in the in-cement group. There was no difference in any of the preoperative variables. Surgical time was shorter for in-cement revisions by a mean of 45 min (p < 0.001). There was no difference in in-hospital stay, surgical complications or readmissions. Implant survival at 5 years was 93.5% for the in-cement and 94.4% for the uncemented revision (p = 0.946). Patient survivorship at 5 years was 62.5% for the in-cement and 69.8% for the uncemented group (p = 0.094). CONCLUSIONS: This study demonstrates that in-cement revision is a valid treatment option for Vancouver B2 fractures, comparable to uncemented stem revision, if certain criteria are met. There was no difference in revision rate, patient survivorship, complications, readmissions or in-hospital stay.

Results of hydroxyapatite ceramic coated primary femoral stem in revision total hip replacement.

PURPOSE: The purpose of this study was to assess survival rate, functional and radiological outcomes when using a hydroxyapatite-ceramic fully coated primary femoral stem in revision total hip arthroplasty. METHODS: Patients who underwent revision total hip arthroplasty using the Furlong hydroxyapatite-ceramic (HAC)-coated (Joint Replacement Instrumentation Ltd., Sheffield, UK) primary stem were retrospectively identified between 2013 and 2017. A total of 30 hips in 27 patients were identified and the mean follow-up duration was 44 months. Post-operative radiographs were scrutinized for signs of component loosening by two independent assessors. Patient's functional outcomes were assessed using the Oxford hip score and compared pre- and post-operatively. The prevalence of thigh pain was assessed at the latest follow-up. RESULTS: The most common cause of revision was adverse reactions to metal debris (ARMD) (46.6%). The overall complication rate was 13.3%. Results at final follow-up demonstrated 100% survival rate and no reported incidence of thigh pain. Using paired t test, all patients had a statistically significant (P < 0.05) improvement in post-operative mean Oxford hip score of 35 compared to a mean pre-operative score of 14. Radiographic analysis of the latest follow-up radiographs revealed no signs of component loosening or component subsidence. CONCLUSION: With a 100% survival rate and excellent reported functional outcomes, we believe that our experience and results support the use of primary cementless stems in selected revision cases.

Arthroscopic versus open ankle arthrodesis.

BACKGROUND: It is thought that arthroscopic ankle fusion offers improved outcomes over open fusion in terms of functional outcomes, time to fusion, length of stay and fewer complications. However, there are doubts about whether correction of established severe deformity can be achieved using the arthroscopic approach. METHODS: A retrospective review of medical records and radiographs at our hospital identified consecutive tibio-talar ankle fusions between April 2009 and March 2014 with minimum 1 year follow up. Records were scrutinised for type of arthrodesis, demographics, length of stay (LOS), time to fusion (TTF), pre- and postoperative deformity, complications and unplanned procedures. Significant factors in the complication group were then compared, using multivariate binary logistic backward stepwise regression to see if any factors were predictive. RESULTS: There were 29 open and 50 arthroscopic ankle fusions (2 converted to open). Mean LOS was 1.93 versus 2.52 days (p=0.590). TTF was shorter after arthroscopic fusion 196d versus 146d (p=0.083). Severe deformity (>10°) was correctable to within 5° of neutral in the majority of cases (97% versus 96%, p=0.903). Union occurred in 83% versus 98% (p=0.0134). The open arthrodesis group had 9 (31%) complications (1 death-PE, 1 SPN injury, 5 non-unions, 1 delayed union and 1 wound infection) and 6 (25%) screw removals. The arthroscopic arthrodesis group had 4 (8%) complications (1 non-union, 1 reactivation of osteomyelitis and subsequent BKA, 1 wound infection, 1 delayed union) with 11 (24%) screw removals. After multi-variant regression analysis of all ankle fusions, low BMI was shown to be associated with complications (p=0.064). CONCLUSIONS: Open arthrodesis was associated with a higher rate of complications and a lower rate of fusion. However, there was no significant difference in terms of LOS and ability to correct deformity compared to arthroscopic arthrodesis. Overall, low BMI was also associated with more complications.

The effect of different methods of stability assessment on fixation rate and complications in supination external rotation (SER) 2/4 ankle fractures.

BACKGROUND: Distinguishing stable supination-external rotation (SER) 2 from unstable SER 4 ankle fractures, using standard radiographs, is controversial. Examination under anaesthesia (EUA), gravity-stress (GS) and weight-bearing (WB) radiographs can aid surgical decision-making. We evaluated the effect of three methods of fracture stability assessment. METHODS: Radiographs and case-notes of 312 consecutive patients with SER 2/4 fractures were reviewed. We recorded ankle stability assessment (plain film (PF) and EUA vs. GS vs. WB radiographs), management (conservative vs. operative), unplanned surgery and complications. RESULTS: Forty five percent assessed with GS underwent surgery (6% for PF/EUA, 4% for WB; P=0.0001). Amongst GS patients, 11% underwent additional surgery (0.1% PF/EUA, 0% WB; P=0.0001). Complications occurred in 2% of the WB group (8% for PF/EUA, 22% for GS; P=0.007). CONCLUSION: This study associates GS assessment with higher rates of surgery and complications. Subsequent studies may determine the longer term effect stability assessments have on post-traumatic arthritis.

Is asymptomatic bacteriuria a risk factor for prosthetic joint infection?

BACKGROUND: Infection is a major complication after total joint arthroplasty. The urinary tract is a possible source of surgical site contamination, but the role of asymptomatic bacteriuria (ASB) before elective surgery and the subsequent risk of infection is poorly understood. METHODS: Candidates for total hip or total knee arthroplasty were reviewed in a multicenter cohort study. A urine sample was cultured in all patients, and those with ASB were identified. Preoperative antibiotic treatment was decided on an individual basis, and it was not mandatory or randomized. The primary outcome was prosthetic joint infection (PJI) in the first postoperative year. RESULTS: A total of 2497 patients were enrolled. The prevalence of ASB was 12.1% (303 of 2497), 16.3% in women and 5.0% in men (odds ratio, 3.67; 95% confidence interval, 2.65-5.09; P < .001). The overall PJI rate was 1.7%. The infection rate was significantly higher in the ASB group than in the non-ASB group (4.3% vs 1.4%; odds ratio, 3.23; 95% confidence interval, 1.67-6.27; P = .001). In the ASB group, there was no significant difference in PJI rate between treated (3.9%) and untreated (4.7%) patients. The ASB group had a significantly higher proportion of PJI due to gram-negative microorganisms than the non-ASB group, but these did not correlate to isolates from urine cultures. CONCLUSIONS: ASB was an independent risk factor for PJI, particularly that due to gram-negative microorganisms. Preoperative antibiotic treatment did not show any benefit and cannot be recommended.

External validation study of hip peri-prosthetic joint infection with cemented custom-made articulating spacer (CUMARS).

INTRODUCTION: Peri-prosthetic joint infection (PJI) is a devastating complication after total hip arthroplasty (THA). The use of custom-made articulating spacers (CUMARS) has been described for use in the first of 2-stage treatment. We report our outcomes of managing PJI using CUMARS. METHODS: Patients undergoing 1st-stage revision using the Exeter standard stem, all-polyethylene acetabulum and antibiotic-loaded cement were identified. Medical records were assessed for demographics, microbiological and operative treatment, complications, eradication of infection and reoperations. No postoperative restrictions were enforced. 2nd-stage revision was undertaken in the presence of pain or subsidence. RESULTS: 53 patients underwent 1st-stage revision using this technique. The average follow-up was 3.9 (range 0.5-7.2) years. Infection was eradicated in 47 (88.7%) patients. 2 patients had chronic infection managed with suppressive antibiotics, 2 patients died before eradication confirmed, 1 patient had raised inflammatory markers but no positive aspiration cultures, 1 patient was lost to follow-up. Complications occurred in 5 (9.4%) patients - 4 dislocations and 1 infected haematoma. 4 patients required a repeated 1st stage. 2nd-stage revision was performed in 19 patients (35%). CONCLUSIONS: The CUMARS technique is an effective way of eradicating PJI after THA. It maintains function by providing a stable construct that permits weight-bearing. It delays or negates the need for 2nd-stage revision. Furthermore, it allows surgeons to choose between managing patients prospectively as a single-stage revision with the option of reverting to a 2nd stage.

Starvation Resulting From Inadequate Dietary Planning for a 50-Day Rowing Expedition.

Meeting the energy demands of prolonged arduous expeditions and endurance sport may be a significant barrier to success. Expedition rowing is associated with high levels of body-mass loss, reflecting the challenge of meeting energy expenditure in this exacting environment. PURPOSE: To use the doubly labeled water (DLW) technique to calculate the total energy expenditure (TEE) and body-composition changes of two 28-y-old healthy male athletes during a 50-d continuous and unsupported row around Great Britain. METHODS: A measured dose of DLW was taken at the start of 2 separate study periods (days 5-19 and 34-48) followed by sequential urine collection, which was analyzed on return to land. RESULTS: Mean TEE was 15.3 MJ/d: athlete 1, 16.4 MJ/d; athlete 2, 14.9 MJ/d. Athlete 1 lost 11.2 kg and athlete 2 lost 14.9 kg of body mass during the row. Average energy provision was 19.1 MJ per 24-h ration pack. CONCLUSIONS: These results highlight the difficulty of maintaining energy balance during expedition rowing. A starvation state was observed despite dietary provision in excess of estimated energy expenditure, indicating that nutritional strategy rather than caloric availability was at fault. The authors recommend that future expeditions prioritize thorough testing and the individualization of rations to ensure that they are both palatable and practical during the weeks to months at sea.

Artificial ligament reconstruction of sternoclavicular joint instability: report of a novel surgical technique with early results.

Symptomatic instability of the sternoclavicular (SC) joint is an uncommon problem. The majority of patients respond well to nonoperative measures, although a small number require reconstructive surgery for symptomatic instability, with varying surgical techniques reported in the literature. We report a series of 5 operations (in 4 patients) with chronic SC joint instability treated by reconstruction of SC and costoclavicular ligaments using an artificial ligament weave (LARS: Ligament Augmentation and Reconstruction System). Preoperative and postoperative disabilities of the Arm, Shoulder, and Hand (DASH) Scores and Oxford Shoulder Scores were collected to evaluate the outcomes. The patients had a mean age of 20 years (range, 17 to 22 y), with 2 male and 2 female patients. Three of the patients had traumatic dislocation of the SCJ and 1 patient had bilateral symptomatic atraumatic instability. Anterior instability was observed in 4 joints and posterior instability in 1 joint. In all cases, reconstruction was achieved with a 30 mm LARS ligament. Postoperative follow-up was for an average of 29 months (range, 19 to 41 mo). The DASH Score improved from 51.7 points (range, 24.2 to 75.0) preoperatively to 13.7 points (range, 8.3 to 20.8) postoperatively. The Oxford Shoulder Scores improved from 20.6 preoperatively (range, 15 to 32) to 41.8 postoperatively (range, 39 to 47). All patients returned to full activity including competitive sports. In conclusion, stabilization of the SC joint using a LARS ligament with a weave technique is a feasible option for young, active patients with symptomatic SC joint instability after failure of nonoperative treatment.