Pathologic fracture and hardware failure in Streptococcus anginosus femoral osteomyelitis: Case report.

INTRODUCTION: Pathologic fracture of the femur due to Streptococcus anginosus osteomyelitis has rarely been described. With limited evidence for treating S. anginosus osteomyelitis, the orthopaedic surgeon is presented with a difficult treatment decision at index presentation. Presented here is a case of failed conservative management, diagnostic dilemma, failed hardware stabilization, and definitive surgical treatment resulting in good clinical outcome. CASE PRESENTATION: A 69-year-old male experienced acute right thigh pain, edema, and erythema after dental treatment 17 days prior. He was diagnosed with right femoral diaphyseal osteomyelitis and Brodie's abscess. Blood cultures grew S. anginosus, but all site-specific tissue cultures resulted negative. Initial management consisted of intravenous antibiotic therapy and percutaneous abscess drainage. Months later, the patient sustained a displaced pathologic fracture of the diaphyseal femur and there was concern for neoplasm, but biopsies were negative. Stabilization was attempted with a lateral plate and screws. This hardware catastrophically failed in the setting of an oligotrophic femoral nonunion. Ultimately, the patient was successfully treated with an intramedullary nail coated with antibiotic-impregnated cement. Twelve months later, the patient achieved clinical and radiographic healing with no evidence of relapse of his osteomyelitis. CLINICAL DISCUSSION: Conservative management of S. anginosus femoral osteomyelitis was inadequate and corroborates the existing literature. S. anginosus osteomyelitis and pyomyositis may be most optimally treated aggressively with early surgical intervention. CONCLUSION: Early surgical debridement and stabilization of the compromised bone with an antibiotic coated intramedullary nail following medullary reaming may prevent pathologic fracture, eradicate infection, and achieve predictable outcomes.

Two-Level Anterior Cervical Discectomy and Fusion Versus Cervical Disc Arthroplasty-Long-Term Evidence Update.

BACKGROUND: Multiple studies have highlighted the motion-sparing benefits of single-level cervical disc arthroplasty (CDA) compared with anterior cervical discectomy and fusion (ACDF). However, few studies have reviewed multilevel ACDF versus CDA. Several recent studies have midterm and even long-term data available comparing 2-level ACDF versus CDA. METHODS: We reviewed 3 reports from 2 large randomized, prospective Food and Drug Administration investigational drug exemption trials looking at 2-level CDA versus ACDF, which provide the bulk of the available midterm to long-term, high-level evidence for the topic. We also present several smaller and/or shorter-term studies. RESULTS: One 5-year study showed that, while both CDA and ACDF showed significant improvement in patient-reported outcome scores, CDA demonstrated greater improvement in Neck Disability Index (NDI) scores than ACDF (mean = -37 versus mean = -28, P = .0003), were more likely to be satisfied (96.4% versus 89.5%, P = .04), had fewer secondary surgeries (4% versus 16.2%, P = .0003), had fewer adjacent level reoperations (3.1% versus 11.4%), and developed less adjacent segment degeneration (50.7% versus 90.5%, P < .0001). Adverse events occurred more frequently with ACDF (8.6% versus 4.4%).Similarly, Lanman et al [Lanman TH, Burkus JK, Dryer RG, Gornet MF, McConnell J, Hodges SD. Long-term clinical and radiographic outcomes of the Prestige LP artificial cervical disc replacement at 2 levels: results from a prospective randomized controlled clinical trial. J Neurosurg Spine. 2017;27(1):7-19] showed that, at 7 years, while both groups demonstrated improvement in patient-reported outcomes, CDA had greater improvement in regard to NDI, neck pain, and Short Form (36) Physical Component Summary scores (each P < .001), had higher rates of satisfaction (94.8% versus 92.6%), had lower rate of secondary surgery at treated levels (4.2% versus 14.7%), and had a lower, albeit not statistically significant, rate of secondary surgeries at adjacent levels (6.5% versus 12.5%). Adverse events were more common with ACDF (7.2% versus 3.2%).More recently, Gornet et al [Gornet MF, Lanman TH, Burkus JK, et al. Two-level cervical disc arthroplasty versus anterior cervical discectomy and fusion: 10-year outcomes of a prospective, randomized investigational device exemption clinical trial. J Neurosurg Spine. 2019;31:508-518.] in 2019 reported 10-year data from the same clinical trial as the Lanman et al report comparing 2-level CDA (209 patients) versus ACDF (188 patients). With >84% follow-up for both groups at 10 years, they found that CDA demonstrated a statistically significantly improved rate of overall success (84% versus 62%) as compared with ACDF. Greater improvements were seen in several other outcome measures for CDA, including NDI, neurological success, and neck pain scores. The CDA group had a lower rate of serious implant-related adverse events and demonstrated a lower rate of needing a secondary surgery at an adjacent level, 9% versus 18% in the ACDF group. CONCLUSIONS: Results of 2 large randomized trials suggest similar-to-improved patient reported outcomes for multilevel CDA versus ACDF maintained out to midterm to long-term follow-up of 5-10 years, with lower rates of revision surgery at index and adjacent levels and lower rates of serious adverse device-related events. LEVEL OF EVIDENCE: 5. CLINICAL RELEVANCE: Comparison of the safety and efficacy of multi-level cervical disc arthroplasty and cervical discectomy and fusion.

Perceived Leg-Length Discrepancy After Primary Total Knee Arthroplasty: Does Knee Alignment Play a Role?

Leg length discrepancy (LLD) is common after total knee arthroplasty (TKA) although its incidence has not been well documented. The purpose of this study was to determine the incidence of perceived LLD before and after primary total knee arthroplasty as well as to determine the correlation between mechanical axis of the knee and perceived LLD. The incidence and time frame of resolution of postoperative LLD was also assessed. Seventy-three patients were prospectively enrolled. Evaluation included patient surveys regarding perceived LLD preoperatively, and at 3- to 6-week, 3-month, 6-month, and 1-year visits. Mechanical axis radiographs were obtained and the relationship of mechanical axis in patients with and without perceived LLD, both before and after surgery, was determined. Analysis was also performed for separate varus and valgus deformities. The effect of surgery on patients' perception of LLD was also determined. Fifty-three patients did not perceive a LLD preoperatively and 18 perceived a LLD preoperatively. Sixty-four patients did not perceive a LLD postoperatively and 7 patients perceived a LLD postoperatively. There was a significant difference in patients who perceived LLD preoperatively and those who perceived LLD postoperatively (P = .035). Of the 7 patients with a perceived LLD postoperatively, all noted resolution of LLD at a mean of 8.5 weeks. There were no statistically significant correlations of knee alignment to perceived LLD in any patient groups. Body mass index and age did not demonstrate any statistical differences between patient groups. Perceived LLD is common in patients undergoing TKA; however, perceived LLD decreases after surgery. Although approximately 10% of patients perceive a LLD after surgery, the vast majority resolve within 3 months. Our study did not show any relationship between mechanical knee alignment and perception of LLD.

Taper Failure After Large-Diameter Metal-on-Metal Total Hip Arthroplasty.

The use of metal-on-metal bearing surfaces for total hip arthroplasty increased dramatically in the past decade for a variety of reasons, including the advantage of using larger-diameter femoral heads to reduce instability. However, recent research suggesting negative outcomes and high failure rates associated with some of these implants has decreased their use. Further, the use of larger-diameter femoral heads on relatively small femoral neck tapers has caused concern about localized corrosion at this junction, particularly with varus femoral alignment and longer femoral neck and head lengths. Although the advent of modular components offers the surgeon greater intraoperative flexibility, this modularity may prove to be a weak link when coupled with large-diameter femoral heads. This report describes a patient with a history of bilateral metal-on-metal total hip arthroplasty complicated by failure of the right hip as a result of fretting and mechanically assisted crevice corrosion. Notching of the femoral neck and head dissociation occurred 10 years after the primary procedure. The authors describe the patient's presenting symptoms, the possible etiology of the catastrophic failure, and the method of treatment and provide a brief review of metal-on-metal implants that may shed some light on the complications in this case. [Orthopedics.2016; 39(5):e984-e987.].

Bilateral extensor mechanism disruption after total knee arthroplasty in two morbidly obese patients.

Disruption of the extensor mechanism as a result of patellar tendon or quadriceps tendon rupture is an uncommon but devastating complication after total knee arthroplasty. Treating a disrupted extensor mechanism can be challenging, particularly in patients who are morbidly obese, due to an increased risk of postoperative complications. Therefore, despite the debilitating nature of extensor mechanism disruption, many community surgeons do not feel comfortable pursuing more complex cases like revision total knee arthroplasty with extensor mechanism allograft on morbidly obese patients, and consequently many of these patients are referred to tertiary-care centers for reconstruction secondary to the complexity of this patient cohort. The authors report 2 cases of bilateral extensor mechanism disruption after total knee arthroplasty in patients who are morbidly obese. One patient experienced trauma leading to her initial rupture; however, her contralateral atraumatic disruption was subsequently diagnosed at a later date. The second patient did not experience trauma leading to either of her extensor mechanism disruptions. Despite substantial medical comorbidities and morbid obesity, revision total knee arthroplasties with extensor mechanism allografts were recommended in both cases in a staged bilateral fashion. The surgical technique is described and the unique challenges afforded by the marked obesity are detailed. The current literature on this subject is reviewed. Despite early complications related to recumbency, this report serves as an example of successful repairs of extensor mechanism disruptions in patients who are morbidly obese, suggesting that extensor mechanism allograft is viable even in patients with high risk of complications.