Role of collateral ligaments in metatarsophalangeal stability: a cadaver study.

BACKGROUND: Lesser metatarsophalangeal joint (MTPJ) instability is a common complaint. The role each of the collateral structures play in maintaining joint stability is unknown. METHODS: Twenty-six fresh-frozen cadaver lesser MTPJ's were tested for instability with the amount of force necessary to translate the joint 3 mm dorsally. Specimens were tested with 1) intact collateral ligaments, 2) transected accessory collateral or proper collateral ligaments (ACL or PCL), 3) repaired ACL or PCL, 4) transected ACL and PCL, 5) repaired ACL and PCL, and 6) transferred interosseous (IO) tendon. Student t-tests were performed to test for statistical significance (p value less than 0.05). RESULTS: The mean force required for 3 mm of dorsal displacement was 25 ± 13 N (range, 11 to 52 N) in the 26 specimens. Transecting either the ACL alone or the ACL and PCL led to the most instability versus transecting the PCL alone. Repairing both ligaments improved stability. The IO tendon transfer was comparable to the direct repair of the PCL but was inferior to the direct repair of the ACL. CONCLUSION: Both ACL and PCL have a stabilizing effect on the MTPJ. However, the ACL was more important since primary transection of the ACL led to more instability and additional transection of the PCL in an ACL deficient model did not lead to significantly more instability. CLINICAL RELEVANCE: Direct repairs of both structures improved the stability of the joint but not back to normal. IO tendon transfer is a possible adjunct to collateral ligament repairs, but in itself is not sufficient to restore stability.

Cost-effectiveness of preoperative nasal mupirocin treatment in preventing surgical site infection in patients undergoing total hip and knee arthroplasty: a cost-effectiveness analysis.

OBJECTIVE: To perform a cost-effectiveness analysis to evaluate preoperative use of mupirocin in patients with total joint arthroplasty (TJA). DESIGN: Simple decision tree model. SETTING: Outpatient TJA clinical setting. PARTICIPANTS: Hypothetical cohort of patients with TJA. INTERVENTIONS: A simple decision tree model compared 3 strategies in a hypothetical cohort of patients with TJA: (1) obtaining preoperative screening cultures for all patients, followed by administration of mupirocin to patients with cultures positive for Staphylococcus aureus; (2) providing empirical preoperative treatment with mupirocin for all patients without screening; and (3) providing no preoperative treatment or screening. We assessed the costs and benefits over a 1-year period. Data inputs were obtained from a literature review and from our institution's internal data. Utilities were measured in quality-adjusted life-years, and costs were measured in 2005 US dollars. MAIN OUTCOME MEASURE: Incremental cost-effectiveness ratio. RESULTS: The treat-all and screen-and-treat strategies both had lower costs and greater benefits, compared with the no-treatment strategy. Sensitivity analysis revealed that this result is stable even if the cost of mupirocin was over $100 and the cost of SSI ranged between $26,000 and $250,000. Treating all patients remains the best strategy when the prevalence of S. aureus carriers and surgical site infection is varied across plausible values as well as when the prevalence of mupirocin-resistant strains is high. CONCLUSIONS: Empirical treatment with mupirocin ointment or use of a screen-and-treat strategy before TJA is performed is a simple, safe, and cost-effective intervention that can reduce the risk of SSI. S. aureus decolonization with nasal mupirocin for patients undergoing TJA should be considered. LEVEL OF EVIDENCE: Level II, economic and decision analysis.

Is total ankle arthroplasty a cost-effective alternative to ankle fusion?

BACKGROUND: Total ankle arthroplasty (TAA) implantation is increasing, as the potential for pain relief and restoration of function and risks are compared with those for ankle fusion. A previous analysis with a simple decision tree suggested TAA was cost-effective compared with ankle fusion. However, reevaluation is warranted with the availability of newer, more costly implants and longer-term patient followup data. QUESTIONS/PURPOSES: Considering all direct medical costs regardless of the payer, we determined if TAA remains a cost-effective alternative to ankle fusion when updated evidence is considered. PATIENTS AND METHODS: Using a Markov model, we evaluated expected costs and quality-adjusted life years (QALY) for a 60-year-old hypothetical cohort with end-stage ankle arthritis treated with either TAA or ankle fusion. Costs were estimated from 2007 diagnosis-related group (DRG) and current procedural terminology (CPT) codes for each procedure. Rates were extracted from the literature. The incremental cost-effectiveness ratio (ICER), a measure of added cost divided by QALY gained for TAA relative to ankle fusion, was estimated. To identify factors affecting the value of TAA, sensitivity analyses were performed on all variables. RESULTS: TAA costs $20,200 more than ankle fusion and resulted in 1.7 additional QALY, with an ICER of $11,800/QALY gained. Few variables in the sensitivity analyses resulted in TAA no longer being cost-effective. CONCLUSION: Despite more costly implants and longer followup, TAA remains a cost-effective alternative to ankle fusion in a 60-year-old cohort with end-stage ankle arthritis.

Early prediction of posttraumatic in-hospital mortality in pediatric patients.

BACKGROUND: The purpose of this study was to develop a triaging tool to predict pediatric in-hospital mortality from data available soon after emergency department (ED) presentation. METHODS: The study group consisted of patients of less than 18 years of age from the National Trauma Data Bank with a reported in-hospital mortality status. Variables analyzed were (1) patient demographics, (2) Glasgow Coma Scale (GCS) values, (3) ED vital signs, (4) injury mechanism, and (5) number of days from trauma until admission. Chi-square-assisted interaction detection (CHAID) profiled patient subgroups. The final cohort was randomly divided into 2 equal sets: a training set to subgroup patients and a testing set to validate the prediction accuracy. RESULTS: The cohort consisted of 224,628 patients with 2.29% in-hospital mortality. Sixteen of 19 potential variables were associated with increased risk of in-hospital mortality. The relative risk of dying was 61.7 times greater (95% confidence interval 57.5-66.1) when CHAID predicted mortality relative to when the model predicted survival (P<0.0001). The most powerful variables of the CHAID model were low total GCS scores and systolic blood pressure in the ED. The CHAID model had an improved relative risk and a better combination of sensitivity and positive predictive value compared with GCS and systolic blood pressure in predicting mortality. CONCLUSIONS: The risk of in-hospital mortality for injured children may be identified soon after arrival in the ED. This information may be used by frontline providers to appropriately triage patients to pediatric trauma centers quickly, to guide resuscitation, and for teaching purposes.

Case report: Bone metastases from fallopian tube carcinoma.

Fallopian tube carcinoma is a rare gynecologic tumor that has metastasized to bone in only one documented case. This case report is of a 56-year-old woman with a primary fallopian tube cancer metastasizing to her right femur and rib cage. This patient was referred to our orthopaedic department from her gynecologic oncologist. A total abdominal hysterectomy and bilateral salpingectomy and oophorectomy revealed fallopian tube cancer. After surgery, the patient had progressive right thigh pain with activity. Radiographs of the femur showed a lytic lesion in the right proximal femur diaphysis with erosion of the medial cortex. We did an open biopsy and curettage of the lesion and intramedullary rod placement. The biopsy confirmed a metastatic lesion arising from the primary fallopian tube cancer. Currently, the patient is recovering and is receiving radiation and chemotherapy. In this case report, we discuss the presentation and treatment course of the patient and summarize the available literature on fallopian tube carcinomas.