Lateral Knee Compartment Portals: A Cadaveric Study Defining a Posterolateral Viewing Safety Zone.

PURPOSE: This study attempted to define a reproducible "safe zone" based on extra- and intra-articular knee anatomy for placing one or 2 accessory portals in the lateral tibiofemoral compartment for posterolateral region viewing. METHODS: Standard portals were created in 10 cadaveric knees to enable posterolateral region arthroscopic lateral tibiofemoral joint compartment viewing. After identifying the lateral knee surface tissue "soft spot," an accessory posterolateral portal (A) was created using an 18-gauge spinal needle and 4-mm cannula under direct visualization of a 70° arthroscope through the anteromedial portal. A second accessory portal (B) was then created 1 cm posterior and 1 cm superior to portal A. Accessory portal locations were measured relative to capsular fold and popliteus tendon locations. Distances from the peroneal nerve, lateral collateral ligament, popliteus tendon, and the biceps tendon were determined. Statistical analysis compared portal location differences from key anatomical structures (P < .05). RESULTS: Accessory portal A (mean ± 95% confidence interval) was located 8.8 ± 2.7 mm from the popliteus tendon, 11.6 ± 2.7 mm from the lateral collateral ligament (LCL), 26.8 ± 2.3 mm from the peroneal nerve, and 4.9 ± 2.5 mm from the biceps tendon. Accessory portal B was located 17.3 ± 2.8 mm from the popliteus tendon, 20 ± 2.8 mm from the LCL, 30.3 ± 3.3 mm from the peroneal nerve, and 7.0 ± 4.8 mm from the biceps tendon. Accessory portal B was located a greater distance from the LCL and the popliteus tendon than portal A (P < .0001). CONCLUSIONS: Using intra- and extra-articular anatomic landmarks, both accessory portals could be safely placed in the lateral tibiofemoral joint compartment to enable posterolateral region viewing. Accessory portals used individually or in combination may enable easier posterolateral region viewing for arthroscopic repair of lateral tibiofemoral compartment structures. CLINICAL RELEVANCE: Lateral tibiofemoral compartment portals can be safely created to enable improved visibility for complex arthroscopic procedures in the posterolateral viewing region.

High Risk of Readmission in Octogenarians Undergoing Primary Hip Arthroplasty.

BACKGROUND: As life expectancy increases, more elderly patients with end-stage hip arthritis are electing to undergo primary THA. Octogenarians undergoing THA have more comorbidities than younger patients, but this is not reflected in risk adjustment models for bundled care programs. The burden of care associated with THA in octogenarians has not been well characterized, and doing so may help these value-based programs make adjustments so that this vulnerable patient population does not risk losing access under accountable care models. QUESTIONS/PURPOSES: The purpose of this study was to describe care use, comorbidities, and complications among octogenarians undergoing primary THA. METHODS: Five percent of the Medicare national administrative claims data was queried to identify patients diagnosed with hip osteoarthritis between January 1, 1998, and December 31, 2013. Patients who underwent primary THA were identified and followed longitudinally during the study period using their unique, encrypted Medicare beneficiary identifiers. We compared risk factors and complications between the octogenarian group versus those aged 65 to 69 years. Multivariate Cox regression was used to evaluate the effect of patient/hospital factors on risk of revision, periprosthetic joint infection, dislocation, venous thromboembolism (VTE), and mortality. Patient factors in the model included age, sex, race, region, socioeconomic status, and health status based on Charlson comorbidity score 12 months before replacement surgery. RESULTS: There were 11,960 THAs in the octogenarians in 1998, which increased to 21,620 in 2013, an 81% increase during this study period. Octogenarians were more likely to have a Charlson score of 3 or higher than those patients aged 65 to 69 years (30% versus 17%, odds ratio [OR] 2.07 [1.98-2.20]; p < 0.001), and they were more likely to have coronary artery disease or congestive heart failure (47% versus 29%, OR 2.16 [2.06-2.26]; p < 0.001). The octogenarian group had a greater risk of dislocation (+12%, p = 0.01), VTE (+14%, p < 0.001), and mortality (+150%, p < 0.001) compared with the younger age cohort. A total of 21% of the octogenarians were readmitted after surgery compared with 12% for patients in the younger group (OR=1.64, 95% confidence interval 1.54-1.75; p < 0.001). CONCLUSIONS: Because octogenarians are at increased risk of dislocation, VTE, medical complications, and mortality after THA, value-based care models that penalize hospitals for readmissions and complications may inadvertently result in loss of access to care for this group of patients as a result of the financial makeup of these bundled care models. Value-based care models were developed to improve care and decrease healthcare costs but may have unintended consequences in the octogenarian with higher complication and readmission risks. Financial losses may lead to institutions from withdrawing from the Bundled Payments for Care Improvement program. To try to prevent this from happening to this vulnerable patient population, bundled care programs should evolve and be modified to allow for risk stratification in the overall payment formula to account for increased age and comorbid conditions to ensure continued successful participation in the program among all the stakeholders. LEVEL OF EVIDENCE: Level III, therapeutic study.

Risk of Reinfection after Irrigation and Debridement of Acute Periprosthetic Joint Infection following TKA.

The purpose of this study was to determine the risk factors associated with reinfection in patients treated with irrigation and debridement (I&D) with liner exchange for an acute (less than 3 months) prosthetic joint infection following the index primary total knee arthroplasty (TKA). Medicare claims database was queried to identify patients with periprosthetic joint infection within 3 months of their index TKA who underwent I&D with tibial polyethylene liner exchange. Exclusion criteria included age < 65 years and < 1 year of claims prior to TKA. A total of 341 patients met our criteria and were analyzed by age, sex, diabetes, obesity, Charlson comorbidity score, and time between TKA and I&D with liner exchange. Average time to I&D with liner exchange following primary TKA was 38.5 ± 21.3 days and multivariate analysis showed a significantly higher risk of reinfection within 1 year in patients > 85 years old (p < 0.001) and diabetes (p < 0.02). The risk of reinfection was lowest for patients treated with I&D with liner exchange within 14 days after TKA (p = 0.028). The incidence of reinfection was 223% greater if I&D with liner exchange was performed 2 to 4 weeks after primary TKA (p < 0.03), and 277% higher if performed > 6 weeks after index procedure compared with those performed within 2 weeks. Patients older than 85 years, diabetics, or treated with I&D with liner exchange > 14 days following the primary TKA had a significantly higher risk of reinfection within 1 year. Patients should be cautioned on the risk of reinfection prior to proceeding with I&D with liner exchange > 2 weeks following the index procedure.

Open and contaminated pediatric pelvic ring injury case report: Fixation without metal.

INTRODUCTION: Pelvic fractures are relatively uncommon in children, accounting for 0.3-7.5% of all pediatric injuries (Gänsslen et al., 2013; Ismail et al., 1996; Peltier, 1965; Galano et al., 2005; Spiguel et al., 2006). This case report describes a pediatric open pelvic injury caused by a crush mechanism between a car and guardrail. CASE: A 13year old male presented with an open APC 3 pelvic injury after being pinned between a car and guardrail. His definitive treatment included bilateral SI screw placement, as well as a less invasive method for anterior pelvic ring disruption (Internal Brace suture anchor dynamic fixation). DISCUSSION/CONCLUSION: A less invasive method for the anterior pelvic ring was used to avoid additional dissection due to extensive soft tissue loss, and to decrease hardware burden, which lessens the chance of complications such as infection. Suture fixation of the pubic symphysis provided stable fixation to allow healing in the current case of open pelvic fracture.