Socioeconomic Status Is Associated with Risk of Above-knee Amputation After Periprosthetic Joint Infection of the Knee.

BACKGROUND: Above-knee amputation (AKA) is a severe but rare complication of TKA. Recent evidence suggests there are sex and racial disparities with regard to AKA after TKA. However, whether lower socioeconomic status is associated with an increased risk of AKA after TKA has not been conclusively established. QUESTIONS/PURPOSES: (1) Is low socioeconomic status or use of public health insurance plans associated with an increased risk of AKA after periprosthetic joint infection (PJI) of the knee? (2) Is race or sex associated with an increased risk of AKA after PJI of the knee? METHODS: This cross-sectional study screened the National Inpatient Sample (NIS) between 2010 and 2014 using the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) procedure and diagnosis codes to identify 912 AKAs (ICD 84.17) among 32,907 PJIs of the knee. The NIS is a large national database of inpatient hospitalizations frequently used by researchers to study outcomes and trends in orthopaedic procedures. The NIS was selected over other databases with more complete followup data such as the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) due to its unique ability to examine income levels and insurance type. Cases were identified by taking all patients with an ICD diagnosis code related to PJI of the knee and limiting that cohort to patients with an ICD procedure code specific to TKA. A total of 912 AKAs after PJI were identified (912 of 32,907, [3%] of all PJIs of the knee) with males comprising 52% of the AKA sample (p = 0.196). Multivariate logistic regression was used to compare risk of AKA after PJI of the knee after controlling for patient demographics, hospital characteristics, and comorbidities. RESULTS: Compared with the wealthiest income quartile by ZIP code, patients in the lowest income quartile by ZIP code were more likely to sustain an AKA (OR = 1.58; 95% confidence interval [CI] 1.25-1.98; p < 0.001). Compared with patients with private insurance, patients with Medicare (OR = 1.94; 95% CI, 1.55-2.43; p < 0.001) and Medicaid (OR = 1.86; 95% CI, 1.37-2.53; p < 0.001) were at higher risk of AKA. There were no differences with regard to risk of AKA for white patients (670 of 24,004 [3%]; OR = 0.99; 95% CI, 0.77-1.26; p = 0.936) and black patients (95 of 3178 [3%], OR = 0.95; 95% CI, 0.69-1.30; p = 0.751) when compared with others (reference, 83 of 3159 [3%]). When compared with female patients, male patients did not have a greater risk of undergoing AKA (OR = 1.02; 95% CI, 0.88-1.29; p = 0.818). CONCLUSIONS: This study did not observe any racial or sex disparities with regard to risk of AKA after PJI. However, there was a greater risk of AKA after PJI for poorer patients and patients participating in Medicare or Medicaid insurance plans. Surgeons should be cognizant when treating PJI in patients from lower income backgrounds as these patients may be at greater risk for AKA. Future research should explore the role of physician attitudes or preconceptions about predicted patient followup in treating PJI, as well as the effect of concurrent peripheral vascular disease on the risk of AKA after PJI. LEVEL OF EVIDENCE: Level III, therapeutic study.

The Cost Effectiveness of Dilute Betadine Lavage for Infection Prophylaxis in Total Joint Arthroplasty.

BACKGROUND: This article presents a break-even analysis for intraoperative Betadine lavage for the prevention of infection in total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: Protocol costs, baseline infection rates after arthroplasty, and average revision costs were obtained from institutional records and the literature. The break-even analysis determined the absolute risk reduction (ARR) in infection rate required for cost effectiveness. RESULTS: At our institutional price of $2.54, dilute (0.35%) Betadine lavage would be cost effective if initial infection rates of both TKA (1.10%) and THA (1.63%) have an ARR of 0.01%. At a hypothetical lowest cost of $0.50, the ARR is so low as to be immediately cost effective. At a hypothetical high price of $40.00, Betadine is cost effective with ARRs of 0.16% (TKA) and 0.13% (THA). CONCLUSION: Intraoperative Betadine lavage, at typical institutional prices, can be highly cost effective in reducing infection after joint arthroplasty.

The Cost-Effectiveness of Preoperative Staphylococcus aureus Screening and Decolonization in Total Joint Arthroplasty.

BACKGROUND: This article presents a break-even analysis for preoperative Staphylococcus aureus colonization screening and decolonization protocols in total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: Protocol costs, baseline infection rates after arthroplasty, and average revision costs were obtained from institutional records and the literature. The break-even analysis determined the absolute risk reduction (ARR) in infection rate required for cost-effectiveness. RESULTS: S aureus nasal screening ($144.07) was cost effective when initial infection rates of TKA (1.10%) and THA (1.63%) had an ARR of 0.56% and 0.45%, respectively. The most inexpensive decolonization treatment ($5.09) was cost effective with an ARR of 0.02% for both TKA and THA. The most expensive decolonization option ($37.67) was cost effective with ARRs of 0.15% (TKA) and 0.12% (THA). CONCLUSION: Preoperative S aureus decolonization can be highly cost effective, whereas colonization screening requires excessively high reductions in infection rate.

Total Knee Arthroplasty in Obesity: In-Hospital Outcomes and National Trends.

BACKGROUND: Both the prevalence of obesity and the utilization rate of total knee arthroplasty are increasing. The rate and proportion of total knee arthroplasty (TKA) performed in the setting of obesity/morbid obesity is increasing significantly over time. METHODS: Using International Classification of Diseases-Ninth Revision codes, we searched the National Hospitals Discharge Survey national database for patients admitted for primary TKA between 2001 and 2010. We then used International Classification of Diseases-Ninth Revision codes for obesity (body mass index = 30-40 kg/m2) and morbid obesity (body mass index, ≥ 40 kg/m2) to select the obese cohorts. RESULTS: We found 29,694 nonobese, 2645 obese, and 1150 morbidly obese patients. There was an increase in each group over time. The rate of obesity/morbid obesity was strongly correlated with time. Obese and morbidly obese patients were more likely to be younger, female, diabetic, and have Medicaid than nonobese patients. Obese and morbidly obese patients had shorter hospital stays and higher home discharge rates than nonobese patients. Obese and morbidly obese patients had lower transfusion rates, shorter hospital stays, and no increase in inpatient wound infection or venous thromboembolic complications than nonobese patients. The Midwest region saw a greater burden of obese TKA patients. CONCLUSION: With the right measures and precautions, satisfactory inhospital outcomes are possible in the obese patient after primary TKA. A limitation of this study is short inhospital stay of the index procedure as complications may present later after discharge.

Impact of close surgical margin on local recurrence and survival in osteosarcoma.

PURPOSE: Whether neoadjuvant chemotherapy safely allows close margins in osteosarcoma patients is still unknown. This study investigates the impact of close margins on local recurrence (LR) and overall survival (OS) for osteosarcoma patients treated with neoadjuvant chemotherapy. METHODS: We retrospectively reviewed 47 cases of conventional osteosarcoma who were treated at our institution. Patient and treatment factors such as age, gender, MSTS stage, tumour site, surgery type, pathological type, tumour size, surgical margin, tumour necrosis rate, chemotherapy regimens and cycles were recorded. A close margin was defined as tumour present less than 5 mm from the closest resection margin. The average followup was 87.6 months (range, 25-135 months). RESULTS: Twenty-five patients were alive, 22 patients had died, and eight had LR. Twenty-eight patients had wide margins, seven had positive margins and 12 had close margins. Positive margins had a greater risk of LR (57.1%) than wide margins and close margins. There was no difference in LR (8.3% vs 10.7%) between close margins and wide margins. Margin status was not correlated with OS. CONCLUSION: Compared with wide margins, close margins did not lead to increased local recurrence in our study group. Whether close margins, as defined in our study, are just as acceptable as wide margins in terms of patient outcomes for osteosarcoma patients with neoadjuvant chemotherapy needs to be further confirmed in the future.

Perioperative infection rate in patients with osteosarcomas treated with resection and prosthetic reconstruction.

BACKGROUND: The incidence of perioperative infection after segmental tumor endoprosthetic replacement in previous reports varies from a high of 7.4% to a low of 2.6%. Appropriate antibiotic use for this group is unknown and controversial, whereas the relationship of antibiotic use and perioperative infection is unclear. QUESTIONS/PURPOSES: We determined the incidence of perioperative infection in patients with osteosarcoma treated with segmental prosthetic replacement using a standard perioperative antibiotic regimen and the incidence of late infections and wound complications. PATIENTS AND METHODS: We retrospectively reviewed the records of 53 patients with osteosarcoma undergoing segmental prosthetic replacements from 1993 to 2008. There were 30 males and 23 females ranging from 10 to 78 years of age. All patients were given intraoperative antibiotics (intravenous cefazolin), continued for 3 days postoperatively and then given orally for 5 days. Patients who were allergic to penicillin or cefazolin were given vancomycin followed by clindamycin. A perioperative infection was defined as a deep infection within 2 months after prosthetic reconstruction. The minimum followup was 1 year (range, 1-15 years). RESULTS: We identified one confirmed perioperative prosthetic infection (1/53; 1.9%) (Enterobacter cloacae and methicillin-resistant Staphylococcus) in a 78-year-old woman after proximal tibial replacement, gastrocnemius flap, and skin graft. Her infection was controlled with débridement, drainage, and intravenous antibiotics. Three patients had late infections, two of which were culture negative. Four patients had wound complications that required further surgery. CONCLUSION: The antibiotic regimen we used is longer than that recommended for patients having routine total joint arthroplasty. Its appropriateness will require comparison with alternate regimens, including those of shorter duration. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Curettage and graft alleviates athletic-limiting pain in benign lytic bone lesions.

BACKGROUND: Solitary bone cysts (SBC), nonossifying fibromas (NOF), and fibrous dysplasia (FD) create benign intramedullary lytic bone lesions. They are typically asymptomatic and treated conservatively. We present a series of lesions that caused performance-limiting pain in young athletes, a symptom phenomenon and possible treatment indication that has been poorly described in the literature. QUESTIONS/PURPOSES: We asked whether intralesional curettage and defect grafting of these lesions would alleviate pain in young athletes and permit their return to unrestricted athletic activities. PATIENTS AND METHODS: We retrospectively identified 29 patients (30 lesions) who underwent curettage and grafting for SBC (12 patients), NOF (nine), or FD (eight). All patients had pain predominantly with athletic involvement. The mean age of the patients was 18 years (range, 12-31 years). Tumor locations were the femur (eight lesions), humerus (seven), tibia (six), fibula (five), pubic ramus (two), ulna (one), and calcaneus (one). Signs/symptoms were pain alone (24 patients) and pain plus fracture (five). Surgery involved curettage and packing with allograft cancellous chips, bone substitute, or demineralized bone matrix. Two patients required internal fixation. The mean followup was 21 months (range, 2-114 months). RESULTS: Twenty-four patients had no pain and five had occasional mild pain at last followup. All patients resumed full activity at a mean of 3.3 months (range, 1.5-8.3 months), excluding two who required repeat surgery. CONCLUSIONS: Our observations suggest curettage and packing with bone graft/substitute can provide pain relief and allow full athletic recovery for young athletes with benign lytic bone lesions. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

The relation of tumour necrosis and survival in patients with osteosarcoma.

PURPOSE: We investigated whether tumour necrosis was associated with disease-free survival (DFS) and overall survival (OS) of osteosarcoma patients treated in our institution. METHODS: We retrospectively studied the predictive value of percentage of necrosis in 40 cases of IIB osteosarcoma treated from 1999 to 2008 in our institution. Patient and treatment factors such as age, gender, tumour site, surgery type, pathological type, tumour size, margin status, percentage of tumour necrosis, chemotherapy regimens and cycles were recorded. The average follow-up was 85.9 months (range, 25-135 months). RESULTS: Two patients had local recurrence (LR) alone, five patients had both LR and metastasis, 14 patients had metastasis alone. Twenty-four patients were alive and 16 had died. The five-year DFS and OS were 47.8% and 65.9%, respectively. Tumour necrosis grouped by 90% was not associated with DFS and OS. Patients with greater than 70% necrosis rate had a significantly higher DFS than those with less than 70%. CONCLUSION: We found no survival advantage at 90% tumour necrosis in our study. Further study with more patients should be performed to evaluate the predictive value of necrosis rate at the cutoff of 70%.

The Cost of Robot-assisted Total Hip Arthroplasty: Comparing Safety and Hospital Charges to Conventional Total Hip Arthroplasty.

INTRODUCTION: Utilization of robotic assistance is increasing for total hip arthroplasty (THA). However, few studies have directly examined the efficacy of this technique at reducing complications. This research aims to compare the rates of perioperative complications of robotic-assisted THA (RA-THA) with conventional THA (C-THA). METHODS: This study screened more than 35 million hospital discharges between 2010 to 2014 using the National Inpatient Sample. The International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) procedure codes were used to identify 292,836 patients who underwent C-THA (ICD 81.51) and 946 patients who underwent RA-THA (ICD 81.51 and ICD 17.41, 17.49). Perioperative complications were identified using ICD-9-CM diagnosis codes. Patient mortality was determined using the Uniform Bill patient disposition. The RA-THA cohort was statistically matched 1:1 to C-THA about patient age, sex, race, comorbidities, hospital type, and calendar year. Mean cost and length of stay (LOS) for each cohort were calculated and compared using the Kruskal-Wallis H test. Logistic regression was used to compare the risks of major and minor complications between the cohorts. RESULTS: We matched 758 (80.13%) RA-THA patients with 758 patients who underwent C-THA. No patient in our sample died. When compared with the conventional group, multivariate analysis revealed that the risk of major complications was similar in RA-THA patients (odds ratio = 0.698, 95% confidence interval = 0.282 to 1.727). In addition, although the rate of minor complications was higher in the RA-THA cohort (21.6% versus 12.5%, P = 0.004), no difference was observed on multivariate analysis (odds ratio = 1.248, 95% confidence interval = 0.852 to 1.829). The average inpatient hospital cost of a RA-THA was $20,046 (SD = 6,165) compared with $18,258 (SD = 6,147) for C-THA (P < 0.001). The average LOS was for RA-THA was 2.69 days (SD = 1.25) compared with 2.82 days for C-THA (SD = 1.18, P < 0.001). DISCUSSION: In a statistically matched cohort, the risk of perioperative complication in patients who underwent RA-THA versus C-THA patients were similar. However, RA-THA was costlier despite shorter LOS. LEVEL OF EVIDENCE: Level III, retrospective cohort analysis.

The Cost-Effectiveness of Vancomycin Powder in Lumbar Laminectomy.

STUDY DESIGN: Break-even cost analysis. OBJECTIVE: The goal of this study is to examine the cost-effectiveness of vancomycin powder for preventing infection following lumbar laminectomy. METHODS: The product cost of vancomycin powder was obtained from our institution's purchasing records. Infection rates and revision costs for lumbar laminectomy and lumbar laminectomy with fusion were obtained from the literature. A break-even analysis was then performed to determine the absolute risk reduction (ARR) in infection rate to make prophylactic application of vancomycin powder cost-effective. Analysis of lumbar laminectomy with fusion was performed for comparison. RESULTS: Costing $3.06 per gram at our institution, vancomycin powder was determined to be cost-effective in lumbar laminectomy if the infection rate of 4.2% decreased by an ARR of 0.015%. Laminectomy with fusion was also determined to be cost-effective at the same cost of vancomycin powder if the infection rate of 8.5% decreased by an ARR of 0.0034%. The current highest cost reported in the literature, $44.00 per gram of vancomycin powder, remained cost-effective with ARRs of 0.21% and 0.048% for laminectomy and laminectomy with fusion, respectively. Varying the baseline infection rate did not influence the ARR for either procedure when the analysis was performed using the product cost of vancomycin at our institution. CONCLUSIONS: This break-even analysis demonstrates that prophylactic vancomycin powder can be highly cost-effective for lumbar laminectomy. At our institution, vancomycin powder is economically justified if it prevents at least one infection out of 6700 lumbar laminectomy surgeries.

Socioeconomic Status Is Associated With the Risk of Girdlestone Resection Arthroplasty After Periprosthetic Infection of the Hip.

INTRODUCTION: Girdlestone resection arthroplasty (GRA) is a radical but sometimes necessary treatment of periprosthetic joint infection (PJI) of the hip. The purpose of this of this study was to identify the independent risk factors for GRA after PJI of the hip. METHODS: This is a retrospective, cross-sectional analysis of the National (Nationwide) Inpatient Sample from 2010 to 2014. The International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) was used to identify 27,404 patients with PJI of the hip, including 889 patients who underwent GRA (ICD-9-CM 80.05). A multivariate model was created to examine the association between GRA and patient characteristics such as age, sex, race, primary payer, median household income, and location and teaching status of the hospital where the procedure was performed. Furthermore, the model controlled for patient comorbidities, including diabetes, anemias, hypertension, congestive heart failure, chronic pulmonary disease, peripheral vascular disease, and drug abuse. RESULTS: The strongest independent risk factor for GRA was Medicare insurance (odds ratio [OR], 1.859, 95% confidence interval [CI], 1.500 to 2.304). Medicaid insurance was also associated with GRA (OR, 1.662, CI, 1.243 to 2.223). Compared with the wealthiest quartile for household income, patients in the poorest quartile (OR, 1.299, CI, 1.046 to 1.614) and second poorest quartile (OR, 1.269, CI, 1.027 to 1.567) were significantly more likely to have a GRA. Furthermore, patients older than 80 years old were at a higher risk of GRA than all other age groups (P < 0.05). No statistical differences were seen regarding patient race or sex. CONCLUSIONS: This study demonstrates that poorer patients, patients with government health insurance plans, and elderly patients are each at independently heightened risk of undergoing a GRA for the treatment of PJI of the hip. LEVEL OF EVIDENCE: III, retrospective cohort study.

Case report: hemosiderotic fibrohistiocytic lipomatous lesion: a clinicopathologic characterization.

BACKGROUND: A hemosiderotic fibrohistiocytic lipomatous lesion, also called hemosiderotic fibrolipomatous tumor, is a rare and recently described fibrolipomatous entity. Initially considered the result of a reactive inflammatory process from trauma or vascular disease, newer evidence suggests it may be neoplastic in origin. CASE REPORT: We report the case of a 56-year-old woman with a painful mass in the dorsal aspect of the foot diagnosed as a hemosiderotic fibrohistiocytic lipomatous lesion. LITERATURE REVIEW: We reviewed all 31 published cases of hemosiderotic fibrohistiocytic lipomatous lesions looking for common clinical, imaging, and histologic patterns. Hemosiderotic fibrohistiocytic lipomatous lesions occur predominantly in the fifth and sixth decades of life (average age, 49.5 years; range, 0.67-74 years). Females predominate 22 to 9. Thirteen of 28 patients had histories of trauma or vasculopathy. Twenty-six of 31 lesions were in the foot. The MRI signal of a hemosiderotic fibrohistiocytic lipomatous lesion follows fat in all sequences. Stranding or septations also frequently are seen. Histologically, the lesions are composed of three main elements in varying proportions: mature adipocytes, spindle cells, and hemosiderin pigment. Ten of 27 resected lesions recurred. Resection types are not reported in many cases. Four of 15 lesions recurred after marginal/intralesional excision, whereas none of three lesions treated by wide excision recurred. PURPOSE AND CLINICAL RELEVANCE: The high recurrence rate may be related to the difficulty in determining intraoperatively that a resection is complete, secondary to the lack of anatomic boundaries such as a pseudocapsule. Any attempt at wide resection must weigh the morbidity of this surgery against that of a recurrence after a resection which seemed complete intraoperatively. There have been no reports of metastasis.

Surgical Approaches for Total Hip Arthroplasty.

Total hip arthroplasty (THA) has become one of the most reliable and patient-requested surgical interventions in all medicine. The procedure can be performed using a variety of surgical approaches, but the posterior approach, direct lateral approach, and direct anterior approach are by far the most common across the globe. This article highlights the history and technique for each of these common approaches. A review of outcomes and complications for each approach are also provided. Each approach has its own unique advantages and disadvantages, but all can be safely and successful utilized for THA. Strong, convincing, high-quality studies comparing the different approaches are lacking at this time. Surgeons are therefore recommended to choose whichever approach they are most comfortable and experienced using. Though not described here, THA can also be done using the anterolateral approach (also known as the Watson Jones approach) as well as the two-incision approach. In addition, recently, some surgeons are utilizing the so-called direct superior approach for THA. While these approaches are far less commonly utilized, they are recognized as viable alternatives to traditional approaches.

Total Hip Arthroplasty and Hemiarthroplasty: US National Trends in the Treatment of Femoral Neck Fractures.

There is controversy regarding whether total hip arthroplasty (THA) or hemiarthroplasty (HA) is the treatment preferred for displaced intracapsular femoral neck fractures (FNFs). Using the US National Hospital Discharge Survey, we found that, of 12,757 patients admitted for FNF between 2001 and 2010, 4.6% underwent THA and 52.5% underwent HA. More of both procedures were performed over time. Mean age was higher for HA patients. Hospitalization duration and blood transfusion rates were higher for THA. There were region-based differences in frequency of THA and significant hospital-size-based differences in frequency of HA, possibly because of differences in regional training and subspecialist availability. In addition, a larger proportion of THA patients was covered by private insurance.

The Evolution of Image-Free Robotic Assistance in Unicompartmental Knee Arthroplasty.

Semiautonomous robotic technology has been introduced to optimize accuracy of bone preparation, implant positioning, and soft tissue balance in unicompartmental knee arthroplasty (UKA), with the expectation that there will be a resultant improvement in implant durability and survivorship. Currently, roughly one-fifth of UKAs in the US are being performed with robotic assistance, and it is anticipated that there will be substantial growth in market penetration of robotics over the next decade. First-generation robotic technology improved substantially implant position compared to conventional methods; however, high capital costs, uncertainty regarding the value of advanced technologies, and the need for preoperative computed tomography (CT) scans were barriers to broader adoption. Newer image-free semiautonomous robotic technology optimizes both implant position and soft tissue balance, without the need for preoperative CT scans and with pricing and portability that make it suitable for use in an ambulatory surgery center setting, where approximately 40% of these systems are currently being utilized. This article will review the robotic experience for UKA, including rationale, system descriptions, and outcomes.

Repair techniques for acute distal biceps tendon ruptures: a systematic review.

BACKGROUND: There is a lack of consensus regarding the optimal surgical approach and fixation method for distal biceps tendon ruptures. The purpose of this study was to conduct a systematic review comparing the results of the various surgical approaches and repair techniques for acute distal biceps tendon ruptures. METHODS: We searched the MEDLINE, Cochrane, and Embase databases for all published randomized controlled trials, prospective cohort studies, or case series that involved primary repairs of acute distal biceps tendon ruptures with use of a cortical button, intraosseous screws, suture anchors, or bone tunnels for fixation. Exclusion criteria included case reports, cadaveric studies, repairs of partial ruptures, revision repairs, and multiple methods of fixation in the same patient. Statistical analysis was performed with use of the chi-square test. RESULTS: Twenty-two studies met the inclusion criteria. The total number of patients was 494 (498 elbows). The complication rate was 24.5% (122 of 498 elbows) overall, and it was 23.9% (seventy-eight of 327) for one-incision procedures and 25.7% (forty-four of 171) for two-incision procedures (p = 0.32). The complication rate was 26.4% (seventy-five of 284) for suture anchors, 20.4% (thirty-four of 167) for bone tunnels, 44.8% (thirteen of twenty-nine) for intraosseous screws, and 0% (zero of eighteen) for cortical button fixation. The complication rate for use of bone tunnels was significantly lower than that for intraosseous screws (p < 0.01). Similarly, the cortical button method proved superior to intraosseous screws (p = 0.01). The most common complication was lateral antebrachial cutaneous nerve neurapraxia (9.6% across all studies, 11.6% for one incision, and 5.8% for two incisions). CONCLUSIONS: The complication rate did not differ significantly between one and two-incision distal biceps repairs; however, the bone tunnel and cortical button methods had significantly lower complication rates compared with suture anchors and intraosseous screws. Further studies are needed to determine the optimal number of incisions.

Tendon sheath fibroma in the thigh.

Tendon sheath fibromas are rare, benign soft tissue tumors that are predominantly found in the fingers, hands, and wrists of young adult men. This article describes a tendon sheath fibroma that developed in the thigh of a 70-year-old man, the only known tendon sheath fibroma to form in this location. Similar to tendon sheath fibromas that develop elsewhere, our patient's lesion presented as a painless, slow-growing soft tissue nodule. Physical examination revealed a firm, nontender mass with no other associated signs or symptoms. Although the imaging appearance of tendon sheath fibromas varies, our patient's lesion appeared dark on T1- and bright on T2-weighted magnetic resonance imaging. It was well marginated and enhanced with contrast.Histologically, tendon sheath fibromas are composed of dense fibrocollagenous stromas with scattered spindle-shaped fibroblasts and narrow slit-like vascular spaces. Most tendon sheath fibromas can be successfully removed by marginal excision, although 24% of lesions recur. No lesions have metastasized. Our patient's tendon sheath fibroma was removed by marginal excision, and the patient remained disease free 35 months postoperatively. Despite its rarity, tendon sheath fibroma should be included in the differential diagnosis of a thigh mass on physical examination or imaging, especially if it is painless, nontender, benign appearing, and present in men.

Early outcomes for malignant peripheral nerve sheath tumor treated with chemotherapy.

OBJECTIVES: Malignant peripheral nerve sheath tumors (MPNST) are rare soft-tissue sarcomas with a tendency for recurrence and metastasis. Treatment using chemotherapy is controversial, but benefit with some agents has been described. This study aimed to analyze early survival outcomes using doxorubicin and ifosfamide chemotherapy for MPNST. METHODS: Pathology records at our musculoskeletal tumor center were searched for patients with a new diagnosis of MPNST between 2003 and 2008. Treatment involved surgical resection, radiation, and chemotherapy with doxorubicin and ifosfamide. Ten patients met inclusion criteria, with mean age 40 years (range, 20-70). Four patients had metastatic disease on presentation. Four patients had neurofibromatosis type I (NF1). RESULTS: Of 6 patients with nonmetastatic disease on presentation, 5 had no evidence of disease post-treatment. The sixth had positive margins after surgery and initially received no further treatment due to noncompliance. Three from this subgroup developed local recurrence, but none developed distant metastases and 1 died of disease at last follow-up. One- and 2-year disease-free survival (DFS) for this subgroup was 80% and 60%, respectively. One- and 2-year overall survival (OS) for the subgroup was 100%. Of 4 patients with metastatic disease on presentation, 2 had no evidence of disease post-treatment. One of these 2 developed local recurrence, but none from the subgroup developed new metastatic disease. Two of these 4 died of disease at last follow-up. One- and 2-year DFS for this subgroup was 100% and 50%, respectively. One- and 2-year OS was 75% and 50%, respectively. Two of the 4 patients presenting with metastatic disease had NF1. All 3 local recurrences and 2 of the 3 deaths in this study occurred in NF1 patients. CONCLUSIONS: For all patients, when combined with surgery and radiation, chemotherapy using doxorubicin and ifosfamide yielded 57% DFS and 80% OS at 2 years. NF1 patients appeared to have worse outcomes, with a statistically significantly lower DFS than non-NF1 patients. Limitations of this study include a small sample size, retrospective design, and use of different chemotherapy regimens.

Spindle-cell hibernoma: a clinicopathologic comparison of this new variant.

Spindle-cell hibernoma is 1 of 4 histologic variants of hibernomas, which are rare lipomatous tumors distinguished from other lipomas by their brown fat component. This article presents a case of a spindle-cell hibernoma that developed in the groin of a 58-year-old man, and is 1 of only 5 known cases of spindle-cell hibernoma published in the scientific literature. Minimal information is available regarding the clinicopathologic characteristics of the 4 hibernoma variants: typical, lipoma-like, myxoid, and spindle-cell. Spindle-cell hibernoma is believed to be the rarest variant, accounting for approximately 2% of hibernomas. The spindle-cell variant predominantly develops in the fourth and fifth decades, with an average age at diagnosis of 42.5 years (range, 28-59 years). It has a male predilection of 4:1. Previously reported only in the posterior neck and scalp, the groin is now added to the sites of spindle-cell hibernoma occurrence. Our patient's tumor demonstrated low-attenuation on computed tomography and contained moderately-attenuating internal septae. Histologically, in addition to the multivacuolated brown fat component common to all hibernomas, spindle-cell hibernoma has a spindle-cell element without vacuolization that is CD34 positive. No prior treatment details are available on this particular variant. Our patient was treated by marginal excision and was disease free through 13 months of follow-up.

Recurrent lipoma-like hibernoma.

This is the fifth report of the rare lipoma-like variant of hibernoma, the 19th case reported, and the first documented as recurring after excision. Our patient was a 56-year-old man whose painful lipoma-like hibernoma (LLH) in the pelvis/buttock was initially treated with marginal excision 15 years earlier. Nine years after treatment, the LLH recurred locally. The recurrence was treated with partial excision and embolization, which alleviated symptoms. The disease was stable 26 months after repeat excision and 202 months after initial treatment. LLH is 1 of the 4 histologic variants of hibernomas, which are rare benign lipomatous tumors distinguished from other lipomas by their brown-fat component. Only minimal information is available regarding the clinicopathologic characteristics of the individual variants. Reviewing the literature, we found that LLH predominantly develops in the fifth and sixth decades, and mean age at diagnosis is 41 years (age range, 2-66 years). LLH has a slight male predilection of 10:9. It most commonly develops in the thigh, with other occurrences reported in the hip, trunk, knee, and calf. The magnetic resonance imaging signal of LLH mirrors fat in all sequences. Presence of internal septations and enhancement with contrast are variable. Histologically, LLH is defined as a hibernoma composed predominantly of univacuolated white-fat cells and only scattered granular or pale hibernoma cells. The literature provides only a few treatment details regarding this variant.