Complete resorption of the humerus in metastatic thyroid carcinoma: a case report.

BACKGROUND: Thyroid carcinoma is the most common endocrinological malignancy, but its spread to bone is rare. Particularly, bone metastases leading to complete resorption of the humerus are extremely uncommon. We aimed to explore factors affecting treatment decision in humeral metastasis by presenting a case and analyze the possible treatments via conducting a literature review. CASE PRESENTATION: We described a case of a 68-year-old woman experiencing chronic pain in her right upper arm for six years. Clinical, radiological, and pathological evaluations confirmed humeral metastasis from thyroid carcinoma. Surgical treatments like tumor removal or limb amputation were suggested for prolonging life and pain relief, but the patient refused them and pursued conservative managements such as herbal medicine, radioactive iodine (131I) therapy, and Levothyroxine Sodium(L-T4). The humeral destruction aggravated gradually, ultimately leading to complete resorption of her right humerus. The patient could not move her right shoulder, but her forearm motion was almost normal; thus, she could complete most of her daily living activities independently. Surgical treatments such as limb amputation were advised but she still refused them for preservation of the residual limb function and preferred conservative managements. CONCLUSION: A personalized multidisciplinary approach is important for patients with bone metastasis. The balance between limb amputation for life-prolonging and pain relief and limb salvage for preservation of residual function and social and psychological well-being should be considered. Our literature review revealed that some novel surgical treatments and techniques are available for bone metastases. This case adds to our current understanding of bone metastases and will contribute to future research and treatments.

Microwave-induced hyperthermia in situ in the treatment of tumors of proximal humerus: long-term results with functionary sparing surgery.

BACKGROUND: The present study aimed to evaluate the indications, feasibility, clinical effectiveness and complications of the treatment with microwave in situ inactivation followed by curettage and bone grafting assisted with internal fixation, for the proximal humerus tumors. METHODS: The clinical data of 49 patients with primary or metastatic tumor of the proximal humerus who received intraoperative microwave inactivation in situ with curettage and bone grafting in our hospital from May 2008 to April 2021 were retrospectively analyzed. RESULTS: There were 25 males and 24 females, with an average age of 57.6 ± 19.9 years (range, 20-81). All patients were followed up for 7 to 146 months, with an average period of 69.2 ± 39.8 months. Up to the last follow-up, 14 patients died. The 5-year overall survival was 67.3%, and 5-year tumor-specific survival was 71.4%. The 5-year tumor-specific survival rates were 100% for aggressive benign tumors or low potential malignancy tumors, 70.1% for primary malignancies, and 36.9% for metastatic tumors. The average preoperative MSTS, constant-Murley and VAS scores were 16.81 ± 3.85, 62.71 ± 12.56 and 6.75 ± 2.47, which were all significantly improved at 6 weeks after operation and at the final follow-up (P < 0.05). CONCLUSIONS: Microwave inactivation in situ and curettage and bone grafting are a feasible treatment for tumors of proximal humeral, especially for malignant tumors and metastases, without the necessity of the replacement of the shoulder, with little trauma and good upper limb function, and with low local recurrence and distant metastasis.

Functional results and unfavorable events after treatment of proximal humerus fractures using a new locking plate system.

BACKGROUND: Proximal humerus fractures are often treated with a fixed-angle titanium plate osteosynthesis. Recently, plates made of alternative materials such as carbon fibre-reinforced polyetheretherketone (CFR-PEEK) have been introduced. This study presents the postoperative results of patients treated with a CFR-PEEK plate. METHODS: Patients with proximal humerus fractures treated with a CFR-PEEK plate (PEEKPower™ Humeral Fracture Plate (HFP)) were included. In follow-up examination, age and gender adjusted Constant-Murley Score (ACS), Subjective Shoulder Value (SSV), Quick Disabilities of the Arm, Shoulder and Hand Score (QDASH) and pain score (Visual Analog Scale (VAS)) were analyzed. General condition at follow-up was measured by European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L). Range of motion was recorded. In addition, radiographs at follow-up, unfavorable events and revision rate were analyzed. RESULTS: In total, 98 patients (66.0 ± 13.2 years, 74 females, 24 males) were reexamined. Mean follow-up was 27.6 ± 13.2 months. There were 15 2-part, 28 3-part and 55 4-part fractures. The functional scores showed good results: SSV 83.3 ± 15.6%, QDASH 13.1 ± 17.0 and ACS 80.4 ± 16.0. A 4-part-fracture, head split component, nonanatomic head shaft reposition and preoperative radiological signs of osteoarthritis were significant negative predictors for poorer clinical scores. Unfavourable events were observed in 27 patients (27.6%). Revision surgery was performed in 8 (8.2%) patients. Risk factors for an unfavourable event were female gender, age of 50 years and older, diabetes, affected dominant hand, 4-part fracture, head split and preoperative radiological signs of osteoarthritis. CONCLUSION: There are several advantages of the CFR-PEEK plate (PEEKPower™ Humeral Fracture Plate (HFP)) such as the polyaxial screw placement and higher stability of locking screws. In summary, the CFR-PEEK plate osteosynthesis is a good alternative with comparable clinical results and some biomechanical advantages. Proximal humerus fractures show good clinical results after treatment with a CFR-PEEK plate. The revision rate and the risk of unfavorable events are not increased compared to conventional titanium plate osteosynthesis. LEVEL OF EVIDENCE: IV.

Reverse Total Shoulder Arthroplasty Is the Most Cost-effective Treatment Strategy for Proximal Humerus Fractures in Older Adults: A Cost-utility Analysis.

BACKGROUND: Proximal humerus fractures are the second-most common fragility fracture in older adults. Although reverse total shoulder arthroplasty (RTSA) is a promising treatment strategy for proximal humerus fractures with favorable clinical and quality of life outcomes, it is associated with much higher, and possibly prohibitive, upfront costs relative to nonoperative treatment and other surgical alternatives. QUESTIONS/PURPOSES: (1) What is the cost-effectiveness of open reduction internal fixation (ORIF), hemiarthroplasty, and RTSA compared with the nonoperative treatment of complex proximal humerus fractures in adults older than 65 years from the perspective of a single-payer Canadian healthcare system? (2) Which factors, if any, affect the cost-effectiveness of ORIF, hemiarthroplasty, and RTSA compared with nonoperative treatment of proximal humerus fractures including quality of life outcomes, cost, and complication rates after each treatment? METHODS: This cost-utility analysis compared RTSA, hemiarthroplasty, and ORIF with the nonoperative management of complex proximal humerus fractures in adults older than 65 years over a lifetime time horizon from the perspective of a single-payer healthcare system. Short-term and intermediate-term complications in the 2-year postoperative period were modeled using a decision tree, with long-term outcomes estimated through a Markov model. The model was initiated with a cohort of 75-year-old patients who had a diagnosis of a comminuted (three- or four-part) proximal humerus fractures; 90% of the patients were women. The mean age and gender composition of the model's cohort was based on a systematic review conducted as part of this analysis. Patients were managed nonoperatively or surgically with either ORIF, hemiarthroplasty, or RTSA. The three initial surgical treatment options of ORIF, hemiarthroplasty, and RTSA resulted in uncomplicated healing or the development of a complication that would result in a subsequent surgical intervention. The model reflects the complications that result in repeat surgery and that are assumed to have the greatest impact on clinical outcomes and costs. Transition probabilities and health utilities were derived from published sources, with costs (2020 CAD) sourced from regional costing databases. The primary outcome was the incremental cost-utility ratio, which was calculated using expected quality-adjusted life years (QALYs) gained and costs. Sensitivity analyses were conducted to explore the impact of changing key model parameters. RESULTS: Based on both pairwise and sequential analysis, RTSA was found to be the most cost-effective strategy for managing complex proximal humerus fractures in adults older than 65 years. Compared with nonoperative management, the pairwise incremental cost-utility ratios of hemiarthroplasty and RTSA were CAD 25,759/QALY and CAD 7476/QALY, respectively. ORIF was dominated by nonoperative management, meaning that it was both more costly and less effective. Sequential analysis, wherein interventions are compared from least to most expensive in a pairwise manner, demonstrated ORIF to be dominated by hemiarthroplasty, and hemiarthroplasty to be extendedly dominated by RTSA. Further, at a willingness-to-pay threshold of CAD 50,000/QALY, RTSA had 66% probability of being the most cost-effective treatment option. The results were sensitive to changes in the parameters for the probability of revision RTSA after RTSA, the treatment cost of RTSA, and the health utilities associated with the well state for all treatment options except ORIF, although none of these changes were found to be clinically realistic based on the existing evidence. CONCLUSION: Based on this economic analysis, RTSA is the preferred treatment strategy for complex proximal humerus fractures in adults older than 65 years, despite high upfront costs. Based on the evidence to date, it is unlikely that the parameters this model was sensitive to would change to the degree necessary to alter the model's outcome. A major strength of this model is that it reflects the most recent randomized controlled trials evaluating the management of this condition. Therefore, clinicians should feel confident recommending RTSA for the management of proximal humerus fractures in adults older than 65 years, and they are encouraged to advocate for this intervention as being a cost-effective practice, especially in publicly funded healthcare systems wherein resource stewardship is a core principle. Future high-quality trials should continue to collect both clinical and quality of life outcomes using validated tools such as the EuroQOL-5D to reduce parameter uncertainty and support decision makers in understanding relevant interventions' value for money. LEVEL OF EVIDENCE: Level III, economic and decision analysis.

Distal humerus hemiarthroplasty for trauma: a systematic review of the outcomes and complications.

BACKGROUND: In patients with distal humerus fractures that are unreconstructible, total elbow arthroplasty is an established alternative to open reduction-internal fixation. Distal humerus hemiarthroplasty is a further alternative to avoid the significant lifestyle limitations associated with total elbow arthroplasty. Distal humerus hemiarthroplasty is an increasingly popular treatment option for unreconstructible distal humeral fractures not amenable to reconstruction. The aim of this systematic review was to assess the literature regarding the functional outcomes and complications of the use of distal humerus hemiarthroplasty for acute trauma. METHODS: A systematic review of the PubMed, Embase, and Scopus databases was performed. The search terms included "distal humerus fracture" OR "elbow fracture" AND "hemiarthroplasty" OR "arthroplasty" OR "replacement." Studies were limited to those published in the English language with reported functional outcome measures and complications. Patient demographic characteristics, implant systems, clinical outcomes (range of motion and functional outcome scores), and complications were extracted. RESULTS: Thirteen studies with a total of 207 patients met the inclusion criteria. The average age ranged from 44 to 79 years, with the mean length of follow-up ranging from 11 to 82 months postoperatively. A mean range-of-motion arc ≥ 93° was achieved in all studies, with 11 of 13 studies achieving mean functional range of motion ≥ 100°. All studies reported good to excellent mean outcome scores. Heterotopic ossification, ulnar cartilage wear, stiffness, and ulnar neuropathy were the most commonly encountered complications. The reoperation rate and revision rate were 17% and 3%, respectively. CONCLUSIONS: Distal humerus hemiarthroplasty is a viable option in the treatment of unreconstructible distal humerus fractures, with good to excellent outcomes expected. Long-term outcome data and the use of distal humerus hemiarthroplasty in younger patients are yet to be fully defined.

Diagnosis and management of medial epicondyle avulsion fracture in a 27-year-old female: A case report.

OBJECTIVE: The purpose of this case report is to describe the diagnosis and management of an adult patient presenting with a rarely reported avulsion fracture of the medial epicondyle of the humerus. CLINICAL PRESENTATION: A 27-year-old female sought care following an injury sustained when the elbow gave out on an attempted back flip. The clinical assessment found an indication of elbow fracture with a diagnosis of medial epicondyle avulsion fracture made on radiographic examination. INTERVENTION AND OUTCOME: Following in-house imaging, the patient was referred for an orthopedic consultation. An MRI was ordered and revealed numerous internal joint derangements. The orthopedist prescribed a hinged brace and followed up in 4 weeks. Physical therapy was ordered by the surgeon with follow-up again in 4 more weeks. CONCLUSION: Medial epicondyle avulsion fractures are extremely rare in adults, and in this case, were accompanied by extensive internal joint derangements in the elbow. Chiropractors should be able to diagnose this condition from x-ray and can be of assistance with rehabilitation therapies.

[Functional results after shoulder hemiarthroplasty for proximal humerus fracture: experience in our center]. / Resultados funcionales tras hemiartroplastía de hombro por fractura de húmero proximal: experiencia en nuestro centro.

INTRODUCTION: shoulder hemiarthroplasty is being relegated as a treatment for non-osteosynthetic proximal humerus fractures. Our objective is to analyze the functional results of patients treated with hemiarthroplasty for this reason in our hospital. MATERIAL AND METHODS: cross-sectional descriptive study that includes patients operated between February 2016 and November 2021; 24 patients, with an average follow-up of 44.6 months. Active joint balance, the Constant-Murley test, the DASH questionnaire and current pain (VAS) were collected. The radiographic parameters analyzed were the number of fracture fragments and the consolidation of the tuberosities. RESULTS: a mean of 71.65 ± 13.75 was obtained in the Constant-Murley and 18.14% ± 13.92 in the DASH. For shoulder flexion, the mean was 108.75° ± 41.26; 104.5° ± 43.68 for abduction and 33° ± 14.73 for external rotation. About internal rotation, 60% of the patients reached the scapular plane. Average VAS was 1.25 ± 1.74. Consolidated tuberosities in 90.5%. There were no significant differences comparing the Constant-Murley test, DASH or rotations between both, over and under 65 years old group of patients. Those over 65 years of age obtained a mean flexion of 125.91° ± 26.82 whereas those under 87.78° ± 26.82 (p = 0.038). The mean abduction in those over 65 was 125.45 ± 28.94 vs 78.89 ± 46.29 in the young group (p = 0.012). CONCLUSION: hemiarthroplasty provides quality of life with acceptable functionality and good pain control, therefore it should continue to be an alternative to consider in selected patients.

INTRODUCCIÓN: la hemiartroplastía de hombro está siendo relegada como tratamiento de fracturas de húmero proximal no osteosintetizables. Nuestro objetivo es analizar los resultados funcionales de los pacientes tratados con hemiartroplastía por este motivo en nuestro centro. MATERIAL Y MÉTODOS: estudio descriptivo transversal que incluye a los pacientes intervenidos entre Febrero de 2016 y Noviembre de 2021; 24 pacientes, con un seguimiento medio de 44.6 meses. Fueron recogidos el balance articular activo, el test de Constant-Murley, el cuestionario DASH y el dolor actual (EVA). Como parámetros radiográficos se analizó el número de fragmentos de fractura y la consolidación de las tuberosidades. RESULTADOS: se obtuvo una media de 71.65 ± 13.75 en el Constant-Murley y de 18.14% ± 13.92 en el DASH. Para flexión de hombro la media fue de 108.75° ± 41.26; 104.5° ± 43.68 para abducción y 33° ± 14.73 para rotación externa. En rotación interna 60% llegaba hasta plano interescapular. EVA medio de 1.25 ± 1.74. Tuberosidades consolidadas en 90.5%. No hubo diferencias significativas entre el Constant-Murley, DASH ni rotaciones de pacientes mayores y menores de 65 años. Los mayores de 65 años obtuvieron flexión media de 125.91° ± 26.82 y los menores de 87.78° ± 26.82 (p = 0.038). La abducción media en mayores de 65 fue de 125.45 ± 28.94 versus 78.89 ± 46.29 en el grupo joven (p = 0.012). CONCLUSIÓN: la hemiartroplastía otorga calidad de vida con aceptable funcionalidad y buen control del dolor, por lo que debe continuar siendo una alternativa a tener en cuenta en pacientes seleccionados.

Reconstruction using a frozen autograft for a skull and humeral lesion of synchronous multicentric osteosarcoma after undergoing successful neoadjuvant chemotherapy: a case report and review of the literature.

BACKGROUND: Synchronous multicentric osteosarcoma (SMOS) is a rare disease characterized by simultaneous multicentricity of intraosseous osteosarcoma without visceral involvement. SMOS, including a skull lesion, which occurs relatively rarely, and reconstruction using a frozen autograft after the excision of a lesion of SMOS has been infrequently reported previously. CASE PRESENTATION: We report an 18-year-old girl with SMOS, with lesions located in the left distal femur, right proximal humerus, and left occipital bone. Her major complaint was pain and swelling around the left knee joint. Asymptomatic lesions of the humerus and skull bone were detected on a systemic bone scan. No visceral organ metastasis was observed. A biopsy of the distal femoral lesion revealed osteosarcoma. Based on the histological findings, multiple bone lesions, and absence of visceral lesion, the clinical diagnosis of SMOS was made. After five courses of neoadjuvant chemotherapy with a regimen of doxorubicin and cisplatin, reconstruction using a tumor prosthesis following wide excision of the left distal femur was performed, and total necrosis was histologically observed in the retracted specimen. Following three cycles of adjuvant chemotherapy, tumor excision and reconstruction with a frozen autograft treated with liquid nitrogen was conducted for both lesions of the humerus and skull, rather than tumor prosthesis or synthetics, in order to retain a normal shoulder function, and to obtain a good cosmetic and functional outcome after treatment of the skull lesion. Further adjuvant chemotherapy could not be administered after the completion of the surgical treatment for all lesions because the adverse events due to chemotherapy were observed. At over 5 years after the diagnosis, she remains clinically disease-free. CONCLUSIONS: An early correct diagnosis, the proper management of chemotherapy, and surgical treatment for all lesions are essential for achieving a good clinical outcome, even in SMOS including a skull lesion. By performing reconstruction using a frozen autograft for a proximal humeral lesion and a skull lesion after confirming the good histological efficacy of neoadjuvant chemotherapy for the primary lesion, the excellent function of the shoulder joint and a good cosmetic outcome at the site of the skull lesion was acquired without complications or recurrence.

Composite reverse shoulder arthroplasty can provide good function and quality of life in cases of malignant tumour of the proximal humerus.

PURPOSE: Management of proximal humeral tumours remains a surgical challenge. No study to date has assessed the quality of life scores following the composite reverse shoulder arthroplasty for this indication. We, therefore, evaluated function and quality of life following reconstruction with allograft for malignant tumour of the humerus. METHODS: A series of six cases of humeral tumour treated by a single surgeon in a single centre was reviewed after a mean follow-up of 5.9 years. The tumours included two chondrosarcomas, one plasmocytoma and three metastases. Resection involved bone epiphysis, metaphysis and diaphysis in five cases (S3S4S5A) and epiphysis and metaphysis in one case (S3S4A). For reconstruction, an allograft composite reverse shoulder arthroplasty was used in all the cases. Outcomes were assessed with range of motion, the QuickDash score and the Short Form 12 (SF-12) Health Survey. Radiographs assessed osseointegration and complications. RESULTS: At the final follow-up, the mean shoulder range of motion were respectively 95°, 57° and 11° for forward flexion, abduction and external rotation. Mean QuickDASH score improved from 28 to 41 and VAS-pain scores improved from 5.1 to 2.3. The post-operative MSTS score was 73% and the Constant score was 46.1/100. The SF-12 PCS and MCS scores were also improved, respectively from 44.4 and 39.7 to 45.5 and 56.1. The mean satisfaction score was 8.1/10. CONCLUSIONS: Composite reverse shoulder arthroplasty is a viable alternative for reconstruction after resection of malignant humeral tumour. Although total tumour resection was the most important objective, the functional and quality of life scores were satisfactory.

Cathodic Voltage-controlled Electrical Stimulation Plus Prolonged Vancomycin Reduce Bacterial Burden of a Titanium Implant-associated Infection in a Rodent Model.

BACKGROUND: Cathodic voltage-controlled electrical stimulation (CVCES) of titanium implants, either alone or combined with a short course of vancomycin, has previously been shown to reduce the bone and implant bacterial burden in a rodent model of methicillin-resistant Staphylococcus aureus (MRSA) implant-associated infection (IAI). Clinically, the goal is to achieve complete eradication of the IAI; therefore, the rationale for the present study was to evaluate the antimicrobial effects of combining CVCES with prolonged antibiotic therapy with the goal of decreasing the colony-forming units (CFUs) to undetectable levels. QUESTIONS/PURPOSES: (1) In an animal MRSA IAI model, does combining CVCES with prolonged vancomycin therapy decrease bacteria burden on the implant and surrounding bone to undetectable levels? (2) When used with prolonged vancomycin therapy, are two CVCES treatments more effective than one? (3) What are the longer term histologic effects (inflammation and granulation tissue) of CVCES on the surrounding tissue? METHODS: Twenty adult male Long-Evans rats with surgically placed shoulder titanium implants were infected with a clinical strain of MRSA (NRS70). One week after infection, the rats were randomly divided into four groups of five: (1) VANCO: only vancomycin treatment (150 mg/kg, subcutaneous, twice daily for 5 weeks); (2) VANCO + 1STIM: vancomycin treatment (same as the VANCO group) coupled with one CVCES treatment (-1.8 V for 1 hour on postoperative day [POD] 7); (3) VANCO + 2STIM: vancomycin treatment (same as the VANCO group) coupled with two CVCES treatments (-1.8 V for 1 hour on POD 7 and POD 21); or (4) CONT: no treatment. On POD 42, the implant, bone, and peripheral blood were collected for CFU enumeration and histological analysis, where we compared CFU/mL on the implants and bone among the groups. A pathologist, blinded to the experimental conditions, performed a semiquantitative analysis of inflammation and granulation tissue present in serial sections of the humeral head for animals in each experimental group. RESULTS: The VANCO + 1STIM decreased the implant bacterial burden (median = 0, range = 0-10 CFU/mL) when compared with CONT (median = 5.7 × 10(4), range = 4.0 × 10(3)-8.0 × 10(5) CFU/mL; difference of medians = -5.6 × 10(4); p < 0.001) and VANCO (median = 4.9 × 10(3), range = 9.0 × 10(2)-2.1 × 10(4) CFU/mL; difference of medians = -4.9 × 10(3); p < 0.001). The VANCO + 1STIM decreased the bone bacterial burden (median = 0, range = 0-0 CFU/mL) when compared with CONT (median = 1.3 × 10(2), range = 0-9.4 × 10(2) CFU/mL; difference of medians = -1.3 × 10(2); p < 0.001) but was not different from VANCO (median = 0, range = 0-1.3 × 10(2) CFU/mL; difference of medians = 0; p = 0.210). The VANCO + 2STIM group had implant CFU (median = 0, range = 0-8.0 × 10(1) CFU/mL) and bone CFU (median = 0, range = 0-2.0 × 10(1) CFU/mL) that were not different from the VANCO + 1STIM treatment group implant CFU (median = 0, range = 0-10 CFU/mL; difference of medians = 0; p = 0.334) and bone CFU (median = 0, range = 0-0 CFU/mL; difference of medians = 0; p = 0.473). The histological analysis showed no deleterious effects on the surrounding tissue as a result of the treatments. CONCLUSIONS: Using CVCES in combination with prolonged vancomycin resulted in decreased MRSA bacterial burden, and it may be beneficial in treating biofilm-related implant infections. CLINICAL RELEVANCE: CVCES combined with clinically relevant lengths of vancomycin therapy may be a treatment option for IAI and allow for component retention in certain clinical scenarios. However, more animal research and human trials confirming the efficacy of this approach are needed before such a clinical recommendation could be made.

Biomechanical effects of calcar screws and bone block augmentation on medial support in locked plating of proximal humeral fractures.

BACKGROUND: The objective of this study was to investigate the biomechanical effects of medial fracture gap augmentation in locked plating of an unstable 2-part proximal humeral fracture with calcar screws and insertion of a corticocancellous bone block. Furthermore the mechanical behavior of dynamic locking screws in the non-parallel arrangement of a proximal humeral plate was of interest. METHODS: Thirty-two fresh frozen humeri were randomized in four equal groups. An unstable 2-part fracture was fixed by locked plating in all specimens. The basic screw setup was supplemented by additional calcar screws in one group. Humeral head screws were replaced by dynamic locking screws in a second group. The third group featured an additional corticocancellous femoral head allograft. Assessment of stiffness was followed by cyclic loading and load to failure tests. Resulting stiffness, fracture gap deflection and ultimate load were compared utilizing Bonferroni corrected t-test for independent samples. FINDINGS: The mechanical effect of additional calcar screws was non-significant as compared to the basic screw configuration whereas bone block insertion significantly increased construct stiffness and failure load. The use of dynamic locking screws did not significantly reduce construct stiffness when compared to conventional locking screws. INTERPRETATION: Additional calcar screws alone did not improve the initial biomechanical properties of an unstable 2-part proximal humeral fracture model. However bone block augmentation appeared to be a reliable alternative of additional bony support by raising stiffness and failure load. Dynamic locking screws did not show their expected dynamic component when used in a non-parallel arrangement.

Electromyogram-based neural network control of transhumeral prostheses.

Upper-limb amputation can cause a great deal of functional impairment for patients, particularly for those with amputation at or above the elbow. Our long-term objective is to improve functional outcomes for patients with amputation by integrating a fully implanted electromyographic (EMG) recording system with a wireless telemetry system that communicates with the patient's prosthesis. We believe that this should generate a scheme that will allow patients to robustly control multiple degrees of freedom simultaneously. The goal of this study is to evaluate the feasibility of predicting dynamic arm movements (both flexion/extension and pronation/supination) based on EMG signals from a set of muscles that would likely be intact in patients with transhumeral amputation. We recorded movement kinematics and EMG signals from seven muscles during a variety of movements with different complexities. Time-delayed artificial neural networks were then trained offline to predict the measured arm trajectories based on features extracted from the measured EMG signals. We evaluated the relative effectiveness of various muscle subsets. Predicted movement trajectories had average root-mean-square errors of approximately 15.7° and 24.9° and average R(2) values of approximately 0.81 and 0.46 for elbow flexion/extension and forearm pronation/supination, respectively.

Biomechanical evaluation of a new fixation technique for internal fixation of three-part proximal humerus fractures in a novel cadaveric model.

BACKGROUND: The optimal surgical treatment for displaced proximal humeral fractures is still controversial. A new implant for the treatment of three-part fractures has been recently designed. It supplements the existing Expert Humeral Nail with a locking plate. We developed a novel humeral cadaveric model and the existing implant and the prototype were biomechanically compared to determine their ability in maintaining interfragmentary stability. METHODS: The bone mineral density of eight pairs of cadaveric humeri was assessed and a three-part proximal humeral fracture was simulated with a Greater Tuberosity osteotomy and a surgical neck wedge ostectomy. The specimens were randomly assigned to either treatment. A bone anchor simulated part of a rotator cuff tendon pulling on the Greater Tuberosity. Specimens were initially tested in axial compression and afterward with a compound cyclic load to failure. An optical 3D motion tracking system continuously monitored the relative interfragmentary movements. FINDINGS: The specimen stabilized with the prototype demonstrated higher stiffness (P=0.036) and better interfragmentary stability (P values<0.028) than the contralateral treated with the existing implant. There was no correlation between the bone mineral density and any of the investigated variables. INTERPRETATION: The convenience of this new IM-nail and locking plate assembly must be confirmed in vivo but the current study provides a biomechanical rationale for its use in the treatment of three-part proximal humeral fractures. The improved stability could be advantageous in particular when medial buttress is missing, even in osteoporotic bone.

Intraosseous calcium migration in calcifying tendinitis: a rare cause of single sclerotic injury in the humeral head (2010: 2b).

Intratendinous deposits of hydroxyapatite crystals are very common, particularly in the rotator cuff. In rare cases, the calcium located in the thickness of the supraspinatus tendon can suffer intraosseous migration into the greater tuberosity. We present a case of this rare entity: a 28-year-old patient who attended with pain and functional weakness in the left shoulder. The plain radiograph showed a sclerotic lesion in the greater tuberosity of the humeral head with a radiolucent halo. The MRI showed a lytic lesion containing the calcium inside and associated with an extensive pattern of oedema of the accompanying bone marrow. A plain radiograph taken 6 months before showed a calcifying tendinitis in the thickness of the supraspinatus tendon. A large number of entities can present as single sclerotic lesions of the humeral head. The diagnostic key lies in the existence of the calcifying tendinitis in the earlier study. The treatment of this disease consists of surgical removal of the calcium. The recognition of this entity is important to avoid unnecessary complementary tests and aggressive surgery, given that the surgical treatment is curative and leads to disappearance of the symptoms.

Tratamiento de la pseudoartrosis séptica y recalcitrante de la diáfisis humeral mediante impactación intramedular / Treatment of the septic and recalcitrant humeral shaft nounion by means intramedullary impactation

Se presenta un caso de una fractura de la diáfisis humeral complicada con una pseudoartrosis recalcitrante, infección y parálisis radial. Se propone una alternativa de tratamiento que, por su sencillez y aplicabilidad, puede incluirse en el arsenal terapéutico para solucionar esta grave patología (AU)

We present a case of humeral shaft fracture complicated with recalcitrant nonunion, infection and radial nerve paralisys. A treatment alternative sets out that, by its simplicity and applicability, deserves to have it in account within the therapeutic arsenal which we arrange to the solution of this serious pathology (AU)

Bone response to a Ca- and P-enriched titanium surface obtained by anodization.

This study evaluated bone response to a Ca- and P- enriched titanium (Ti) surface treated by a multiphase anodic spark deposition coating (BSP-AK). Two mongrel dogs received bilateral implantation of 3 Ti cylinders (4.1 x 12 mm) in the humerus, being either BSP-AK treated or untreated (machined - control). At 8 weeks postimplantation, bone fragments containing the implants were harvested and processed for histologic and histomorphometric analyses. Bone formation was observed in cortical area and towards the medullary canal associated to approximately 1/3 of implant extension. In most cases, in the medullary area, collagen fiber bundles were detected adjacent and oriented parallel to Ti surfaces. Such connective tissue formation exhibited focal areas of mineralized matrix lined by active osteoblasts. The mean percentages of bone-to-implant contact were 2.3 (0.0-7.2 range) for BSP-AK and 0.4 (0.0-1.3 range) for control. Although the Mann-Whitney test did not detect statistically significant differences between groups, these results indicate a trend of BSP-AK treated surfaces to support contact osteogenesis in an experimental model that produces low bone-to-implant contact values.

Bone response to a Ca- and P-enriched titanium surface obtained by anodization

This study evaluated bone response to a Ca- and P- enriched titanium (Ti) surface treated by a multiphase anodic spark deposition coating (BSP-AK). Two mongrel dogs received bilateral implantation of 3 Ti cylinders (4.1 x 12 mm) in the humerus, being either BSP-AK treated or untreated (machined - control). At 8 weeks postimplantation, bone fragments containing the implants were harvested and processed for histologic and histomorphometric analyses. Bone formation was observed in cortical area and towards the medullary canal associated to approximately 1/3 of implant extension. In most cases, in the medullary area, collagen fiber bundles were detected adjacent and oriented parallel to Ti surfaces. Such connective tissue formation exhibited focal areas of mineralized matrix lined by active osteoblasts. The mean percentages of bone-to-implant contact were 2.3 (0.0-7.2 range) for BSP-AK and 0.4 (0.0-1.3 range) for control. Although the Mann-Whitney test did not detect statistically significant differences between groups, these results indicate a trend of BSP-AK treated surfaces to support contact osteogenesis in an experimental model that produces low bone-to-implant contact values.

O objetivo desse estudo foi avaliar a resposta do tecido ósseo à superfície de titânio (Ti) enriquecida com Ca e P obtida por anodização (BSP-AK). Três cilindros de Ti (4,1 x 12 mm) BSP-AK ou usinado (controle) foram implantados bilateralmente nos úmeros de dois cães de raça indefinida. Oito semanas após a implantação, os fragmentos ósseos contendo os implantes foram removidos e processados para análises histológica e histomorfométrica. A formação óssea foi observada na região cortical e no canal medular até aproximadamente um terço da extensão do implante. Na maioria dos casos, feixes de fibras colágenas dispostos paralelamente à superfície do implante foram observados na região medular. Nessa região observaram-se também áreas focais de formação de matriz mineralizada e osteoblastos ativos. Os implantes do grupo BSP-AK apresentaram média de contato osso-implante 2,3 por cento, com medidas variando de 0,0 a 7,2 por cento e os do grupo controle tiveram média 0,4 por cento, com medidas variando de 0,0 a 1,3 por cento. Apesar do teste de Mann-Whitney não mostrar diferença estatisticamente significante entre os grupos, nossos resultados indicaram uma tendência para a ocorrência de osteogênese de contato na superfície BSP-AK em um modelo experimental que resulta em baixos valores de contato osso-implante.

Infraclavicular brachial plexus block versus humeral block in trauma patients: a comparison of patient comfort.

In this prospective randomized study, we compared humeral block (HB) and infraclavicular brachial plexus block (ICB) with pain caused by the block as a primary outcome, assuming that ICB would cause less pain than HB. Patients undergoing emergency upper limb surgery were included in this study and received either ICB (group I, n = 52 patients) or HB (group H, n = 52 patients). Patients were asked to quantify the severity of the pain during the procedure using a visual analog scale from 0 to 100 mm and to identify which of the 4 components of the procedure was most unpleasant (skin transfixion, needle redirection in search of the nerves, local anesthetic injections, or electrical stimulation). The block was assessed every 5 min for 30 min after completion of the block. Overall visual analog scale scores for the block were 35 +/- 27 mm in group H versus 19 +/- 18 mm in group I (P < 0.0011). Electrical stimulation was the most unpleasant part of the block (group H, 29 +/- 15 mm versus group I, 15 +/- 10 mm) (P < 0.019). Time to perform the block was significantly shorter in group I (ICB, 6 +/- 4 min versus HB, 10 +/- 4 min; P < 0.0001). The onset time was 13 +/- 7 min for ICB and 9 +/- 3 min for HB (P < 0.05). No serious complications were observed. In summary, ICB is less painful, compared with HB, with a similar success rate.

Percutaneous intramedullary decompression, curettage, and grafting with medical-grade calcium sulfate pellets for unicameral bone cysts in children: a new minimally invasive technique.

Several treatment options exist for unicameral bone cysts (UBCs), including observation, steroid injection, bone marrow injection, and curettage and bone grafting. These are all associated with high recurrence rates, persistence, and occasional complications. Newer techniques have been described, most with variable success and only short follow-up reported. Because of these factors, a new minimally invasive percutaneous technique was developed for the treatment of UBCs in children. Twenty-eight children with UBCs who underwent percutaneous intramedullary decompression, curettage, and grafting with medical-grade calcium sulfate (MGCS) pellets by the senior author (J.P.D.) between April 2000 and April 2003 were analyzed as part of a pediatric musculoskeletal tumor registry at a large tertiary children's hospital. Four patients were lost to follow-up, and the remaining 24 patients had an average follow-up of 21.9 months (range 4-48 months). Twelve patients were followed for at least 24 months. Six of the 24 children had received previous treatment of their UBC, most often at an outside institution. Follow-up was performed through clinical evaluation and radiographic review. Postoperative radiographs at most recent follow-up showed complete healing, defined as more than 95% opacification, in 22 of 24 patients (91.7%). One patient (4.2%) demonstrated partial healing, defined as 80% to 95% opacification. One patient had less than 80% radiographic healing (4.2%). All 24 patients returned to full activities and were asymptomatic at most recent follow-up. The only complication noted was a superficial suture abscess that occurred in one patient; this resolved with local treatment measures. The new minimally invasive technique of percutaneous intramedullary decompression, curettage, and grafting with MGCS pellets demonstrates favorable results with low complication and recurrence rates compared with conventional techniques. The role of intramedullary decompression as a part of this percutaneous technique is discussed.