Devitalized Autograft Associated with the Vascularized Fibula Graft: Irradiation versus Freezing Methods.

BACKGROUND: Among the alternatives for the management of malignant bone tumors is the "devitalized autograft associated with vascularized fibula graft." The devitalization process is achieved by pasteurization, irradiation, or freezing. The combination of these grafts has been broadly researched for more than 25 years. However, there is no research currently published comparing the various methods or their respective outcomes. METHODS: A retrospective study was compiled of 26 devitalized autografts associated with vascularized fibula performed to limb salvage of malignant bone tumors. They were divided into two groups according to the devitalization method: either freezing (12 procedures) or irradiation (14 procedures). Clinical, radiographic, and scintigraphic results were assessed at least 24 months after surgery. RESULTS: The union rates reached 83.3% in the freezing group and 92.8% in the irradiated group but did not express different outcomes. Scintigraphic viability was observed in all the grafts that achieved radiographic union (Mann-Whitney U-test: p = 0.005). Three patients had nonunion, with only one having no viability in the scintigraphy (Mann-Whitney U-test: p = 0.001). There was no malignant recurrence in the autograft, only in surrounding soft tissues. Local recurrence was statistically higher in larger tumors (Mann-Whitney U-test: p = 0.025). CONCLUSION: Both groups presented similar union rates and are considered safe to devitalize bone graft despite different outcomes observed. The survivor rates observed could be limited by the existence of the techniques.

Leprosy with ulnar nerve abscess: ultrasound findings in a child.

We report the ultrasound findings of a typical case of nerve abscess due to leprosy in an 11-year-old boy. The patient had previously undergone pediatric multibacillary leprosy multidrug therapy (MDT) in accordance with World Health Organization guidelines. He presented to our service with bilateral ulnar neuritis with no response to prednisone (1 mg/kg). Right ulnar nerve ultrasound revealed nerve hypoechogenicity, fascicular pattern disorganization, marked fusiform thickening, and a round anechoic area suggestive of intraneural abscess. Intense intraneural power Doppler signal was detected, indicating active neuritis. Intravenous methylprednisolone had a poor response and the patient was submitted to ulnar nerve decompression, which confirmed nerve abscess with purulent discharge during surgery. As the patient weighed more than 40 kg, treatment with a pediatric dose was considered insufficient and adult-dose MDT was prescribed, with improvement of nerve pain and function. Although leprosy is rare in developed countries, it still exists in the USA and it is endemic in many developing countries. Leprosy neuropathy is responsible for the most serious complications of the disease, which can lead to irreversible impairments and deformities. Nerve abscess is an uncommon complication of leprosy and ultrasound can efficiently demonstrate this condition, allowing for prompt treatment. There is scant literature about the imaging findings of nerve abscess in leprosy patients. Radiologists should suspect leprosy in patients with no other known causes of neuropathy when detecting asymmetric nerve enlargement and nerve abscess on ultrasound.

Evaluation of the COVID-19 Infection Rate in the Perioperative Period of Elective Surgeries of the Hand and Microsurgery.

BACKGROUND: After the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic (coronavirus disease 2019 [COVID-19]), the world started reducing the number of elective surgeries to reduce the transmission of the coronavirus. Some priority elective surgeries were performed, and there was no increase in contagion rates due to safety protocols and protection measures. The study aims to present the coronavirus infection rate of elective hand surgeries and microsurgery performed during pandemics. METHODS: A retrospective study evaluating 188 patients submitted to elective surgical procedures. The exclusion criteria were patients infected by COVID-19 before the surgery and patients who submitted to trauma surgery. Only 108 patients were eligible for this study. The mean age was 47.8 years (range: 15 days-81 years). There were 63 females and 45 males. They were divided into 2 groups: outpatient (n = 49) and inpatient (n = 59) procedures. RESULTS: The overall COVID infection rate was 6.48%. The outpatient infection rate was 2.08%, whereas the inpatient infection rate was 10.17% (Student t test: P = .089). The main factor correlated with infection in the postoperative period was the number of postoperative outpatient visits (Student t test: P = .089). No statistical differences were observed between the variables studied, but there was a tendency for patients who submitted to inpatient surgery to get infected by COVID-19 (P = .089). The statistical power was 0.8 (Cohen's d test), showing that large samples are needed to analyze the correlation better. CONCLUSION: We concluded that the safety of performing elective hand surgery during the pandemic remains unclear, and more studies with larger samples are needed.

Impact of COVID-19 on the Work, Health, and Quality of Life of Brazilian Hand Surgeons.

BACKGROUND: To evaluate the impact of coronavirus disease 2019 (COVID-19) on the clinical practice, health, and quality of life of Brazilian hand surgeons when only essential services and emergency procedures were being provided. METHOD: A questionnaire of 50 questions was sent to members of the Brazilian Society of Hand Surgery addressing work and life routines before the pandemic and during the initial quarantine period from April to August 2020. RESULTS: Two hundred ten hand surgeons answered the questionnaire; 55.2% lived in the southeast region and worked in the capital and metropolitan regions, in both the private and public systems. Thirty-eight percent of the sample had other sources of income besides medicine, and due to a drop of 50% or more in the volume of consultations and surgeries, one-third had to apply for financial loans or access personal savings, and 69% made financial cuts in their domestic and life routines. More than 40% gained weight and stopped doing physical activities, while 20% lost weight and started physical activities. Approximately 30% were diagnosed with COVID-19, 92% of whom had mild symptoms and quarantined at home, and 89% had psychological symptoms such as anxiety, fear, insecurity, and insomnia. CONCLUSIONS: Coronavirus disease 2019 had a significant impact on the lives of Brazilian hand surgeons by drastically reducing the number of consultations and surgical procedures, generating not only financial difficulties but also changes in the exercise routine, changes in body weight, associated psychological symptoms, and changes in the family/life routine.

Total Wrist Arthrodesis: A Preoperative Test to Predict Functional Outcomes.

Objective The study aims to demonstrate an evaluation method to predict the functional success of total wrist arthrodesis (TWA) and assist its indication. Methods A prospective study including ten patients submitted to (TWA) posttraumatic arthritis. Exclusion criteria were patients who lost postoperative follow-up or incomplete information in the medical record. The objective functional assessment (handgrip strength, three-point pinch, lateral pinch and pulp-pulp pinch) and the subjective functional assessment (DASH, PRWE, EVA) were evaluated in 3 different periods: (1) Before surgery without articular anesthesia, (2) Before surgery under articular anesthesia and (3) 12 weeks after the surgical procedure. Results There was an increase in handgrip strength in all three pinches measurements after pain relief, both after joint anesthesia and after the consolidation of the arthrodesis (p < 0.05). In the comparisons between the subjective evaluations (DASH, PRWE and VAS), the patients had better scores in the postoperative evaluation after 12 weeks (p < 0.05). There was no statistical difference when comparing the mean strength values found after anesthesia and after 12 weeks of TWA. Conclusion the outcomes could propose an assessment protocol for patients with indication for TWA, in which patients with good response to intra-articular anesthetic infiltration would benefit from the effects of the surgical procedure.

Trigger Finger or De Quervain Tenosynovitis after Surgical Treatment for Carpal Tunnel Syndrome.

Objective To evaluate the open surgical treatment for carpal tunnel syndrome as a risk factor for the development of stenosing tenosynovitis that results in trigger finger and De Quervain disease. Materials and Methods A retrospective study analyzing the medical records of patients submitted to open surgical release of carpal tunnel syndrome between 2010 and 2021 in a secondary- and tertiary-level hospital. The following data were collected: pathological history, duration of the follow-up after the surgical treatment for carpal tunnel syndrome, development of trigger finger or De Quervain tenosynovitis, affected fingers, and the interval between the end of surgery and symptom onset. Results We evaluated 802 patients of both genders and with a mean age of 50.1 (±12.6) years. The mean follow-up was of 13 (±16.4) months. The mean time until the development of trigger finger was of 61.4 months, and of 73.7 months for De Quervain disease. The incidence of development of De Quervain disease was of 4.12%, and for trigger finger it was of 10.2%. The most affected digits were the thumb (47.6%), the middle (24.4%), and the ring finger (8.54%). Age was the only factor that showed an association with the risk of developing trigger finger, with an increase of 2% for each increase in age of 1 year. Conclusion The incidence rates for the development of De Quervain disease (4.12%) and trigger finger (10.2%) after the surgical treatment for carpal tunnel syndrome were like those described in the literature. Only age was a factor that influenced the development of trigger finger.

Effectiveness of low-level laser therapy for patients with carpal tunnel syndrome: design of a randomized single-blinded controlled trial.

BACKGROUND: Carpal tunnel syndrome is the most common neuropathy in the upper extremity, resulting from the compression of the median nerve at wrist level. Clinical studies are essentials to present evidence on therapeutic resources use at early restoration on peripheral nerve functionality. Low-level laser therapy has been widely investigated in researches related to nerve regeneration. Therefore, it is suggested that the effect of low-level laser therapy associated with other conservative rehabilitation techniques may positively affect symptoms and overall hand function in compressive neuropathies such as carpal tunnel syndrome. The aim of this study is to evaluate the effectiveness of low-level laser therapy in addition to orthoses therapy and home orientations in patients with carpal tunnel syndrome. METHODS/DESIGN: Patients older than 18 years old will be included, with clinical diagnosis of carpal tunnel syndrome, excluding comorbidies. A physiotherapist will conduct intervention, with a blinding evaluator. Randomization will be applied to allocate the patients in each group: with association or not to low-level laser therapy. All of them will be submitted to orthoses therapy and home orientations. Outcome will be assessed through: pain visual analogic scale, Semmes Weinstein monofilaments™ threshold sensibility test, Pinch Gauge™, Boston Carpal Tunnel Questionnaire and two point discrimination test. DISCUSSION: This paper describes the design of a randomized controlled trial, which aim to assess the effectiveness of conservative treatment added to low-level laser therapy for patients with carpal tunnel syndrome. TRIAL REGISTRATION: Brazilian Clinical Trials Registry (ReBec) - 75ddtf / Universal Trial Number: U1111-1121-5184.

Arthroscopic Management for Carpometacarpal Boss of Third Joint and Synovectomy: Technique and Case Report.

The carpometacarpal boss (CMCB) is painful bony prominence in the dorsum of the hand that can lead to functional and aesthetic impairment. Nonoperative methods are the management of choice, achieving good outcomes. However, operative management could be an alternative in the absence of improvement. Nevertheless, open procedures are more likely to be done, but there are complications, and it is more aggressive to the soft tissue. The use of arthroscopic techniques has increased in the last decade, being a safe alternative for CMCB management. It has the advantage of being a minimally invasive technique, allowing the early range of motion. This minimally invasive method allows synovectomy and preserves tendon attachments, achieving good functional outcomes. This case report presents an arthroscopic technique for managing the middle finger CMCB.

Corrective Fifth Metacarpal Neck Osteotomy and Intramedullary Screw Fixation Technique: Technique and Case Report.

Malunion of metacarpal fractures can result in severe functional and esthetic impairment to the patient, thus requiring surgical correction. Traditionally, the fixation methods most commonly used for these fractures are the Kirschner wires or the plates and screws. However, one of the options for the fixation of metacarpal fractures is intramedullary fixation with a headless screw. This minimally invasive method can also be used for corrective metacarpal osteotomies. It has the advantages of being a minimally invasive technique and allowing the early range of motion. This minimally invasive method can also be used to stabilize the corrective metacarpal osteotomies for malunion. This case report presents a minimally invasive technique for corrective dorsal metacarpal osteotomy and fixation with a headless intramedullary screw. This alternative fixation method has the advantage of low damage to soft tissues and good functional outcomes.

SURGICAL TREATMENT FOR RHIZARTHROSIS: A SYSTEMATIC REVIEW OF THE LAST 10 YEARS.

Introduction: Comparison of different surgical techniques to treat patients with rhizarthrosis or carpometacarpal osteoarthritis of the thumb. Materials and Methods: A systematic review was conducted using three electronic databases. Randomized, controlled trials in patients who underwent surgery for the treatment of rhizarthrosis were included. The literature review followed the PRISMA protocol. Results: A total of 15 articles involving a total population of 958 patients were selected. Seven different surgical techniques were compared. Conclusions: We conclude that no procedure is superior to another in terms of pain, physical function, overall patient assessment, range of motion, or strength. Outcome measurements should be standardized to enable better comparison between surgical techniques. Level of evidence II, Systematic Review.

Introdução: Comparação de diferentes técnicas cirúrgicas em pacientes com rizartrose ou osteoartrite carpometacárpica do polegar. Materiais e Métodos: A revisão sistemática foi conduzida em três bancos de dados eletrônicos. Foram incluídos estudos clínicos randomizados e controlados com pacientes submetidos ao tratamento cirúrgico para tratamento de rizartrose. A revisão da literatura seguiu o protocolo PRISMA. Resultados: Foram selecionados 15 artigos, envolvendo uma população total de 958 pacientes. Foram comparadas sete técnicas cirúrgicas distintas. Conclusões: Concluímos que nenhum procedimento é superior a outro em termos de dor, função física, avaliação geral do paciente, amplitude de movimento ou força. A mensuração dos desfechos obtidos devem ser padronizadas a fim de possibilitar melhor comparação entre as técnicas cirúrgicas assim como, permitir uma análise estatística fidedigna. Nível de Evidência II; Revisão Sistemática.

Evaluations of Repaired Artery Patency in Forearm Wounds Using the Allen Test, Handheld Doppler and Doppler Ultrasonography.

Objective The purpose of the present study was to evaluate the rate of patency in the postoperative period of arterial injuries of the forearm secondary to penetrating trauma. The injuries were subjected to primary repair and examined with the Allen test and a handheld Doppler device, and the results were later confirmed with Doppler ultrasonography. Methods Eighteen patients were included, with a total of 19 arterial lesions, 14 ulnar lesions, and 5 radial lesions; one patient had lesions on both forearms. All patients underwent surgery and three clinical evaluations: the Allen test and assessment of arterial blood flow by a handheld Doppler device at 4 and 16 weeks after surgery and Doppler ultrasonography performed at 12 weeks after surgery. Results At the first clinical evaluation, 77% of the patients had patency based on the Allen test, and 72% had a pulsatile sound identified by the handheld Doppler device. In the second evaluation, 61% of the patients had patency based on the Allen test, and the rate of pulsatile sound by the handheld Doppler device was 72%, similar to that observed 2 months earlier. Based on the Doppler ultrasonography evaluation (∼12 weeks after surgery), the success rate for arteriorrhaphy was 88%. Regarding the final patency (Doppler ultrasonography evaluation) and trauma mechanism, all patients with penetrating trauma had patent arteries. Conclusion We conclude that clinical evaluation using a handheld Doppler device and the Allen test is reliable when a patent artery can be palpated. However, if a patent artery cannot be located during a clinical examination, ultrasonography may be required.

External Delta Fixator in the Postoperative Management of Microsurgical Flaps in the Lower Limb: Experience of a Tertiary Hospital.

Objective To evaluate the use of external fixators in the delta-type kickstand configuration as an adjuvant method in the postoperative period of patients submitted to free flaps in the lower limbs. Methods A total of 17 external delta fixators were used in patients submitted to free flaps in the lower limbs. The surgical technique was performed in a standardized manner, with the distal pin located 6 cm proximally to the anastomosis, and the proximal pin, 6 cm distally to the anterior tuberosity of the tibia. Results The mean age of the sample was of 34.76 years (range: 15 to 66 years). In total, 11 men and 6 women were selected. The posterior tibial artery was used in 14 cases, and the anterior tibial artery, in 3 cases. The mean time of use of the external fixators was of 3.88 weeks. The rate of reoperation was of 17.64%; that of retail loss was of 11.76%; that of success rate was of 88.23%; and the rate of infection was of 5.9%. Conclusion The use of delta-type fixators as an adjunct method in the postoperative period is reliable; however, more studies are needed to evaluate its true role in the postoperative period.

Internal Fixation of Scaphoid Nonunion with Humpback Deformity Using Iliac Graft and Volar Plate: Series of Eight Cases.

Objectives The aim of the present article is a clinical and radiographic evaluation of scaphoid nonunion with humpback deformity using an iliac graft and a volar plate. Methods Eight patients were followed-up prospectively, all male, with a mean age of 39.6 years old, with scaphoid waist nonunion, with an average of 19 months of trauma without previous surgery. The patients were treated with a graft removed from the iliac crest and a 1.5 mm blocked volar scaphoid plate (Medarthis AG, Basel, Switzerland). The patients were followed-up with radiographic evaluations and computed tomography (CT) scans in the preoperative period and 1 month, 3 months, 6 months and 1 year after the operation. The carpal height and the scaphosemilunar and intrascaphoid angles were measured preoperatively, 3 months, and 1 year postoperatively. The function was assessed preoperatively and repeated 1 year postoperatively using the Disabilities of the Arm, Shoulder, and Hand (DASH) and Patient-related Wrist Evaluation (PWRE scores), as well as by measurement of forceps clamp and wrist and thumb range of motion. Results All cases were consolidated, with an average time of 3.38 months. Two complications were observed: an infection of the iliac surgical wound and a plaque element placed in the scapholunate space. Two patients opted to remove the implant because they had a painful click at maximum wrist flexion. There was improvement in the parameters of wrist and thumb range of motion and pinch strength in all measurements, with statistical significance for the PRWE and the scapholunate angle. Conclusion Although our sample was small, we achieved consolidation in all cases; the complications were expected in the literature and there were improvements in the radiographic patterns, in the functional assessment, and in the pain scale of our patients.

Diagnostic Failure Rate in Detecting Perilunate Carpal Fractures and Dislocations Using Plain Wrist X-Rays.

Objectives The present study aimed to evaluate the diagnostic failure rate in detecting perilunate fractures and dislocations using plain wrist radiographs by orthopedists and orthopedic residents. A secondary objective was to identify possible groups with a greater or lesser chance of establishing a correct diagnosis. Methods An online questionnaire was sent to several orthopedists through e-mail, social networks, and smartphone-based communication applications to assess the rate of diagnostic failure in detecting perilunate fractures and dislocations using plain radiographs. Results A total of 511 responses was obtained, with a diagnostic error rate of 8.81% for simple dislocations and 1.76% for trans-scaphoid perilunate fractures. Group stratification showed that residents presented the highest error rates in simple perilunate dislocations (23.91%), whereas hand surgeons presented the lowest error rates (1.74%). Conclusion Compared with the literature, the failure rates found were lower, suggesting that plain radiography is effective and that the error rate may not be as high as reported.

Distal radius fracture fixation using volar plate: A comparative study evaluating the biomechanical behavior of uni and bicortical distal screws.

Extensor tendon ruptures caused by bicortical screws impingement following distal radius fracture fixation with volar plates are extensively reported in the literature. Thus, a biomechanical study comparing unicortical and bicortical fixations in intra-articular distal radius fracture models is critical in decision-making regarding distal radius fracture management. Forty-two synthetic radius models were fixed using a variable angle volar distal locking plate with seven screws. They were divided into 6 groups (n = 7): G1/G3/G4 unicortical fixation (75% of anteroposterior distal radius lenght); G2/G4/G6 bicortical fixation. Each group underwent a different mechanical test: axial compression (G1/G2), dorsal flexion (G3/G4), and volar flexion (G5/G6). The load application rate was 5 mm/min and 1000 cycles of 50 to 250 N at 1 Hz were performed between both static tests. Comparative results in the first static test, in the second static test, and in failure generally showed a very similar behavior. Models depicted similar behavior in the second static test when cyclic load was performed. Therefore, one can realize that stiffness differed during dorsal flexion only in the first static test. Maximum force to break the model in axial compression was greater in bicortical than in unicortical construct. Since biomechanical properties are similar, we recommend using unicortical distal locking screws in distal radius fracture fixation with volar plates to prevent extensor tendon ruptures.

Comparative effects of wavelengths of low-power laser in regeneration of sciatic nerve in rats following crushing lesion.

Peripheral nerves are structures that, when damaged, can result in significant motor and sensory disabilities. Several studies have used therapeutic resources with the aim of promoting early nerve regeneration, such as the use of low-power laser. However, this laser therapy does not represent a consensus regarding the methodology, thus yielding controversial conclusions. The objective of our study was to investigate, by functional evaluation, the comparative effects of low-power laser (660 nm and 830 nm) on sciatic nerve regeneration following crushing injuries. Twenty-seven Wistar rats subjected to sciatic nerve injury were divided into three groups: group sham, consisting of rats undergoing simulated irradiation; a group consisting of rats subjected to gallium-aluminum-arsenide (GaAlAs) laser at 660 nm (10 J/cm(2), 30 mW and 0.06 cm(2) beam), and another one consisting of rats subjected to GaAlAs laser at 830 nm (10 J/cm(2), 30 mW and 0.116 cm(2)). Laser was applied to the lesion for 21 days. A sciatic functional index (SFI) was used for functional evaluation prior to surgery and on days 7, 14, and 21 after surgery. Differences in SFI were found between group 660 nm and the other ones at the 14th day. One can observe that laser application at 660 nm with the parameters and methods utilised was effective in promoting early functional recovery, as indicated by the SFI, over the period evaluated.

Reliability, validity and responsiveness of Brazilian version of QuickDASH.

OBJECTIVE: To analyse the construct validity, test-retest reliability and responsiveness of the Brazilian version of Quick-DASH (QD-Br) in patients with upper limb disorders. METHOD: Participants completed the full Brazilian DASH, the QD-Br and the SF-12 Brazil questionnaires at the beginning of treatment, after 48-72h and the after 2-12 months. Construct validity was analysed by Pearson's correlation coefficient (r). To evaluate the test-retest reliability we used the Intraclass Correlation Coefficient (ICC) and the Cronbach's alpha coefficient to test the internal consistency. Responsiveness was analysed by Standardized Response Mean (SRM) and Effect Size (ES). The Minimal detectable change (MDC) score was based upon calculations of the standard error of measurement (SEM), confidence interval of 95%. RESULTS: The construct validity presented strong direct correlation with the total QD-Br score and the Brazilian DASH (r = 0.91), a moderate inverse correlation between the total QD-Br score and the physical component of the SF- 12 Brazil (r = -0.55) and weak inverse correlation between the QD-Br and the mental component of SF-12 Brazil (r = -0.49). The ICC test-retest showed good reliability of 0.81 (0.72-0.87). QD-BR presented high responsiveness, with ES of 1.06 and SRM of 0.94. The MDC was 17.27 points. CONCLUSION: These results provide evidence that the QD-Br was a valid, reliable and responsive instrument when utilized in patients with upper limb traumatic and no-traumatic disorders in the Brazilian population.

Morphologic and morphometric evaluation of experimental acute crush injuries of the sciatic nerve of rats.

In order to qualify and quantify nerve fiber lesion following an acute crush injury, a morphologic and morphometric study was carried out in 25 Wistar rats divided into five groups of five animals each according to the crushing load applied, i.e., 500, 1,000, 5,000, 10,000, and 15,000 g. The injury was produced under general anesthesia on a 5mm-long intermediate segment of the right sciatic nerve for 10 min using a dead-weight machine. The animals were killed with an excessive dose of anesthetics 72 h later and submitted to perfusion with a fixing solution through the abdominal aorta immediately after death. Both the right and left sciatic nerves were removed and prepared for histologic and morphometric examinations; 5 microm-thick sections stained with 1% Toluidine blue were examined under a light microscope equipped with a video camera linked to a computer loaded with a graphic program (KS 400). The morphometric studies included measuring total number of fibers, fiber density, fiber diameter, myelin fiber area, axon diameter, axon area and G ratio. The results showed that damage to the nerve fibers began to appear as early as with the 500 g load and was similar in all groups despite the load applied, increasing with the 10,000 and 15,000 g loads, although the external supporting tissues and small diameter fibers were preserved. The predominant type of lesion produced was axonotmesis.

Is the Sciatic Functional Index always reliable and reproducible?

The Sciatic Functional Index (SFI) is a quite useful tool for the evaluation of functional recovery of the sciatic nerve of rats in a number of experimental injuries and treatments. Although it is an objective method, it depends on the examiner's ability to adequately recognize and mark the previously established footprint key points, which is an entirely subjective step, thus potentially interfering with the calculations according to the mathematical formulae proposed by different authors. Thus, an interpersonal evaluation of the reproducibility of an SFI computer-aided method was carried out here to study data variability. A severe crush injury was produced on a 5 mm-long segment of the right sciatic nerve of 20 Wistar rats (a 5000 g load directly applied for 10 min) and the SFI was measured by four different examiners (an experienced one and three newcomers) preoperatively and at weekly intervals from the 1st to the 8th postoperative week. Three measurements were made for each print and the average was calculated and used for statistical analysis. The results showed that interpersonal correlation was high (0.82) in the 3rd, 4th, 5th, 7th and 8th weeks, with an unexpected but significant (p<0.01) drop in the 6th week. There was virtually no interpersonal correlation (correlation index close to 0) on the 1st and 2nd weeks, a period during which the variability between animals and examiners (p=0.24 and 0.32, respectively) was similar, certainly due to a poor definition of the footprints. The authors conclude that the SFI method studied here is only reliable from the 3rd week on after a severe lesion of the sciatic nerve of rats.

SPRING PLATES IN DISTAL RADIO FRACTURES: "IN VITRO" MECHANICAL PROPERTIES.

BACKGROUND: Distal radius fractures are one of the most common orthopedic injuries and appear in various patterns. Volar plate fixation is not always considered the gold standard treatment. OBJECTIVE: To measure the resistance of a fragment-specific fixation assembly model obtained by plate fixation associated with different K-wire sizes. METHOD: In this original experimental study, novel II, axial compression of bone materials was tested. RESULTS: In both groups, the maximum force supported by the fixation method in our study was ten times greater than the physiological load to which the wrist was subjected under physiological conditions. DISCUSSION: In this study, we obtained encouraging results when compared to results reported in the literature. Our study showed that our bone fixating system was mechanically adequate for articular fractures of the intermediate column of the radius (Melone classification). The results were similar or superior to the results of pressure resistance and stiffness when data from the literature was used as reference. CONCLUSION: The proposed fixation method demonstrated adequate resistance for fixation of the intermediate column of the distal radius. Increasing K wire size caused augmented resistance of the fixation. Level of Evidence II, Prospective comparative study.

INTRODUÇÃO: A fratura da extremidade distal do rádio é uma afecção frequente, com variedade de apresentações e nem sempre são passíveis de fixação volar única. OBJETIVO: Quantificar a resistência obtida no modelo experimental de fixação do fragmento específico, utilizando fio de Kirschner pré moldado, associado a fixação proximal com placa e parafuso. MÉTODOS: Estudo experimental original, nível II, no qual foram realizados ensaios mecânicos com objetivo de avaliar a resistência a compressão axial. RESULTADOS: Os valores de força máxima suportada pelo método de fixação foram pelo menos 10x maiores do que a carga fisiológica a qual o punho é submetido. DISCUSSÃO: A fixação do tipo fragmento específico vem se mostrando útil e segura, permitindo uma mobilidade precoce segura. Os resultados analisados demonstraram que a montagem proposta em nosso estudo foi mecanicamente adequada para a fixação das fraturas articulares da borda volar ulnar (classificação de Melone) do rádio, tendo resultados semelhantes ou superiores quando comparados a literatura, avaliando a rigidez e a pressão o qual o sistema foi submetido. CONCLUSÃO: O método de fixação proposto demonstrou resistência adequada para fixação das fraturas da coluna intermediária do rádio. O aumento da espessura do fio provocou um aumento da força resistida da montagem. Nível de Evidência II, Estudo prospectivo comparativo.