[Translated article] Current situation of robotics in knee prosthetic surgery: A technology that has come to stay?

Robotic surgery is a surgical technique that is on the rise. The goal of robotic-assisted total knee arthroplasty (RA-TKA) is to provide the surgeon with a tool to accurately execute bone cuts according to previous surgical planning to restore knee kinematics and balance of soft tissue, being able to precisely apply the type of alignment that we choose. In addition, RA-TKA is a very useful tool for training. Within the limitations, there is the learning curve, the need for specific equipment, the high cost of the devices, the increase in radiation in some systems and that each robot is linked to a specific type of implant. Current studies show, with RA-TKA, variations in the alignment of the mechanical axis are reduced, postoperative pain is improved and earlier discharge is facilitated. On the other hand, there are no differences in terms of range of motion, alignment, gap balance, complications, surgical time or functional results.

Current situation of robotics in knee prosthetic surgery, a technology that has come to stay? / Situación actual de la robótica en cirugía protésica de rodilla, ¿una tecnología que ha venido para quedarse?

Robotic surgery is a surgical technique that is on the rise. The goal of robotic-assisted total knee arthroplasty (RA-TKA) is to provide the surgeon with a tool to accurately execute bone cuts according to previous surgical planning to restore knee kinematics and balance of soft tissue, being able to precisely apply the type of alignment that we choose. In addition, RA-TKA is a very useful tool for training. Within the limitations, there is the learning curve, the need for specific equipment, the high cost of the devices, the increase in radiation in some systems and that each robot is linked to a specific type of implant. Current studies show, with RA-TKA, variations in the alignment of the mechanical axis are reduced, postoperative pain is improved and earlier discharge is facilitated. On the other hand, there are no differences in terms of range of motion, alignment, gap balance, complications, surgical time or functional results.

Mortality Rates of Patients with Proximal Femoral Fracture in a Worldwide Pandemic: Preliminary Results of the Spanish HIP-COVID Observational Study.

BACKGROUND: The outbreak of coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), in December 2019 in Wuhan, People's Republic of China, has developed into an unprecedented pandemic with enormous pressure on health-care providers around the world. A higher mortality rate has been described in older infected individuals. Patients with hip fracture are a particularly vulnerable population during this pandemic because older age is associated with a higher mortality rate. Our aim was to describe the early mortality rate and demographic variables in a hip fracture sample population in Spain during the coronavirus pandemic. METHODS: This is a multicenter, observational, retrospective, descriptive study. We collected data from 13 major hospitals in Spain from the beginning of the national state of alarm (declared on March 14, 2020, by the Spanish government) until the end of our study period on April 4, 2020. All patients who were ≥65 years of age, presented to the Emergency Department of the participating hospitals during this period with a diagnosis of proximal femoral fracture, and had a minimum follow-up of 10 days were included in the cohort. In addition to mortality, demographic and other potential prognostic variables were also collected. RESULTS: In this study, 136 patients with a hip fracture were included. Of these patients, 124 underwent a surgical procedure and 12 were managed nonoperatively. The total mortality rate was 9.6%. Sixty-two patients were tested for COVID-19, with 23 patients being positive. The mortality rate for these 23 patients was 30.4% (7 of 23 patients) at a mean follow-up of 14 days. The mortality rate was 10.3% (4 of 39) for patients who had been tested and had a negative result and 2.7% (2 of 74) for patients who had not been tested. Of the 12 patients who were managed nonoperatively, 8 (67%) died, whereas, of the 124 patients who were surgically treated, 5 (4%) died. Results differed among centers. CONCLUSIONS: There is a higher mortality rate in patients with a hip fracture and an associated positive test for COVID-19. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Teaching Patients How to Reduce a Shoulder Dislocation: A Randomized Clinical Trial Comparing the Boss-Holzach-Matter Self-Assisted Technique and the Spaso Method.

BACKGROUND: There are many different techniques for reducing acute anterior dislocations of the shoulder, and their use depends on surgeon preference. The objective of this study was to compare the pain experienced by a patient performing a self-reduction technique with the pain felt during a reduction performed by a trained physician. METHODS: The study was carried out at the emergency department of a tertiary referral center. Patients between 18 and 60 years of age with an acute anterior shoulder dislocation were randomly allocated into 2 groups. In 1 group the emergency doctor actively guided the reduction process with the Spaso technique (Sp group), and in the other group the patient used the Boss-Holzach-Matter (also known as Davos or Aronen) self-reduction technique (BHM group). The pain experienced by the patient during the reduction was recorded by means of a visual analogue scale (VAS) ranging from 0 to 10. Other recorded data included demographic characteristics, reduction time, and success rate. RESULTS: Of 378 patients assessed for eligibility from May 2015 until February 2017, 197 did not meet the inclusion criteria, 58 met exclusion criteria, 22 declined to participate, and 41 withdrew before randomization. Sixty acute anterior shoulder dislocations were randomized into the Sp group (n = 30) or the BHM group (n = 30). The BHM group experienced significantly less pain during reduction than the Sp group (p = 0.047), with mean pain scores of 3.57 (standard deviation [SD] = 2.1]) and 5.26 (SD = 2.9), respectively. No significant difference between groups was found with respect to reduction time (105 seconds [range, 10 to 660 seconds] in the Sp group and 90 seconds [range, 5 to 600 seconds] in the BHM group; p = 0.6) or success rate (67% and 77%, respectively; p = 0.39). CONCLUSIONS: The self-reduction technique results in less pain than, and is as efficient in achieving reduction of anterior shoulder dislocations as, the Spaso technique. These findings favor the use of the self-assisted method as an effective first-line treatment for shoulder dislocations seen in the emergency department as well as its use by patients with recurrent dislocation. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Cross-linked polyethylene does not reduce wear in total knee arthroplasty. / El polietileno de alto entrecruzamiento no reduce el desgaste en la artroplastia total de rodilla.

AIM: To compare two different types of inserts: Ultra-high molecular weight polyethylene (UHMWPE) and cross-linked polyethylene with a quantitative and qualitative study of polyethylene wear particles in synovial fluid 3 years after total knee arthroplasty. MATERIAL AND METHODS: A prospective, randomized, controlled cohort study with blinded evaluation was carried out on 25 patients undergoing staged bilateral total knee replacement, 6 months apart. Knee arthrocentesis was performed on 12 patients 3 years after surgery, and the polyethylene particles were analyzed. RESULTS: No significant differences were found in the number of particles generated by the two different types of inserts at 3 years from total knee arthroplasty (3,000×: x¯ cross-linked=849.7; x¯ UHMWPE=796.9; P=.63; 20,000×: x¯ cross-linked=66.3; x¯ UHMWPE=73.1; P=.76). Likewise, no differences in the probability of finding elongated (χ2=0.19; P=.66) or rounded (χ2=1.44; P=.23) particles in both types of inserts were observed. However, the probability of finding fibrillar particles is 3.08 times greater in UHMWPE. CONCLUSIONS: Cross-linked polyethylene does not significantly reduce the generation of polyethylene particles in patients with total knee arthroplasty, 3 years after the surgical procedure.

Home-based intravenous analgesia with elastomeric pump as an outpatient procedure for pain control after anterior cruciate ligament repair. / Analgesia intravenosa domiciliaria mediante bomba elastomérica como procedimiento ambulatorio de control del dolor en la reparación del ligamento cruzado anterior.

OBJECTIVE: To follow up pain in the immediate postoperative period, using an elastomeric pump in anterior cruciate ligament surgery. MATERIAL AND METHODS: 309 patients who had undergone anterior cruciate ligament repair with bone-tendon-bone allograft. Pain control was assessed with a visual analogue scale (VAS) during the immediate postoperative period, in the postoperative care unit, in the recovery room, and after the first 24-48-72hours following home discharge. The need for rescue medication, adverse effects observed and emergency visits were also registered. RESULTS: 309 patients were assessed (264 males, 45 females), mean age 33 (range: 18 - 55). Postoperative pain was mild in 44.7% of patients, and 38.5% were pain-free. At discharge, 41.1% of patients reported mild pain and 57% were pain-free. At home, mild to moderate levels of pain were maintained and over 97% of patients presented VAS values ≤ 3. Fewer than 3% had adverse effects, 8.7% had to use analgesic medication at some point. Pruritus occurred in less than 1% of patients receiving intravenous analgesia at home, and fewer than 2% had device-related complications. DISCUSSION: There is no consensus regarding the postoperative management of anterior cruciate ligament lesions, although most surgeons use multimode anaesthesia and different combinations of analgesics to reduce postoperative pain. CONCLUSIONS: The use of an intravenous elastomeric pump as postoperative analgesia for anterior cruciate ligamentoplasty has yielded good results.

Transcultural adaptation, validation and assessment of the psychometric properties of the spanish version of the Western Ontario Shoulder Instability Index questionnaire. / Adaptación transcultural, validación y valoración de las propiedades psicométricas, de la versión española del cuestionario Western Ontario Shoulder Instability Index.

OBJECTIVE: The aim of the present study is to present a transcultural adaptation and validation of the Western Ontario Shoulder Instability Index questionnaire into Spanish (Spain), and to assess its psychometric properties. MATERIAL AND METHODS: The transcultural adaptation was conducted according to sequential forward and backward translation approach. A pilot study was subsequently performed to ensure acceptable psychometric properties. The Western Ontario Shoulder Instability Index questionnaire was administered to 79 patients twice within a period of 2 months, and patients were stratified into 3 groups (cohorts). RESULTS: CONCLUSIONS: The Spanish version of the Western Ontario Shoulder Instability Index questionnaire is a valid, reliable tool, and highly sensitive to change to assess patients with shoulder instability.

SECOT-GEDOS consensus on pre-surgical pain management in knee and hip arthrosis.

OBJECTIVE: To develop recommendations, based on best evidence and experience, on pain management in patients undertaking total knee or hip replacement. METHODS: Nominal group methodology was followed. A group of experts was selected (5 orthopedics, 1 anesthesiologist), who defined the scope, users, topics, preliminary recommendations, and 3 systematic reviews: efficacy and safety of pre-surgical analgesia regarding to post-surgical pain, efficacy and safety of pre-emptive analgesia and pre-operative factors of post-operative pain. The level of evidence and grade of recommendation was established using the Oxford Centre for Evidence Based Medicine, and the level of agreement with the Delphi technique (2 rounds). The Delphi was extended to 39 orthopedics and anesthesiologists. The whole document was reviewed by all the experts. RESULTS: A total of 21 recommendations were produced. They include specific pharmacological treatment, as well as the evaluation and monitoring of patients on this treatment, and post-operative pre-emptive treatment. Agreement above 70% was reached in 19 recommendations. CONCLUSIONS: In patients undergoing total knee or hip replacement, a proper evaluation, follow-up, pharmacological and non-pharmacological treatment of predictors of poor surgical outcomes should be performed, especially those related to pre-operative pain. This can improve post-operative pain and surgery outcomes.

Secondary patellar resurfacing in the treatment of patellofemoral pain after total knee arthroplasty.

PURPOSE: This paper reports a prospective review of patients who, between 2004 and 2007, underwent secondary patellar resurfacing (SPR) due to anterior knee pain after a primary total knee arthroplasty (TKA). The aim was to evaluate the clinical outcomes obtained with the SPR and to compare them with radiological findings. METHODS: A total of twenty-seven consecutive patients met the inclusion criteria. There were twenty-three (85%) women and four (15%) men with a median age of 70 years. The patients were evaluated before and after the surgery with the same functional scores and radiological parameters. Bone scintigraphy was also used in the assessment, and a CT-scan was performed in order to evaluate the femoral component rotation. The median time between TKA and SPR was 18 months. RESULTS: With a median follow-up of 23 months, seventeen patients (63%) reported a clear subjective improvement after SPR, and patellofemoral scores (primary outcome measure), KSS and WOMAC (secondary outcome measures) showed a statistically significant improvement following the procedure. There were no significant changes after SPR in the Insall-Salvati ratio, the lateral patellar displacement or the lateral patellar tilt. The mean time between TKA and SPR had no statistically significant effect on outcome. The bone scintigraphy revealed increased patellar uptake in seven cases, but this was not related to subsequent improvement after SPR. Rotational computed tomography showed a median internal rotation of the femoral component of 1º. The complications observed were a patellar component loosening and an acute post-infection. CONCLUSION: No clinical or radiological parameter was found to be related to the final outcome after SPR. There was a discrepancy between functional scale scores and the patient's subjective satisfaction.

Intramedullary versus extramedullary tibial cutting guide in severely obese patients undergoing total knee replacement: a randomized study of 70 patients with body mass index >35 kg/m2.

BACKGROUND: Patients with obesity have an increased risk of osteoarthritis of the knee, which can lead to the need for total knee replacement (TKR). TKR may be more complex in obese patients and the correct orientation of the implant is more difficult. We selected patients with body mass index (BMI) >35 kg/m(2) undergoing TKR and studied the utility of an intramedullary tibial cutting guide in facilitating the correct orientation of the tibial implant. METHODS: Seventy patients with BMI >35 kg/m(2) were selected for a prospective, randomized study. Patients were divided into two groups: In group 1 (n=31), the tibial component was implanted using the aid of a intramedullary tibial guide. In group 2 (n=39), the tibial component was implanted using the aid of an extramedullary tibial cutting guide. RESULTS: The two groups were comparable with respect to age, BMI, and degree of preoperative deformity. Mean age was 69.35 in group 1 and 70.06 in group 2. Group 1 had a mean BMI of 39.84 kg/m(2) and group 2 of 40.05 kg/m(2). Postoperative orientation of the femur and tibia and the mechanical axis were within the normal range in both groups. A statistically significant difference between the two groups was observed in tourniquet time, which was longer in group 2 than in group 1 (p=0.038). CONCLUSION: Two types of guide were compared in correctly orienting the tibial component of the TKR in patients with a BMI >35 kg/m(2). The lesser tourniquet time in the group in which the intramedullary guide was used suggest its usefulness because the positioning and orientation of the tibial cut was carried out more rapidly and anatomical references were not needed for correct orientation, as it is guided by the anatomical axis of the tibia. The use of the intramedullary guide reduces surgical time in these patients.

Knee osteotomy: navigation guided and arthroscopy assisted.

The aim of this work is to describe the procedure used, which combines navigation, arthroscopy and fluoroscopic control, and to evaluate its usefulness in complex osteotomies around the knee. The consolidation of the osteotomy was obtained without complications by obtaining a correct axis of the limb in three spatial planes. This is a precise and reproducible technique. It does not need computer support, associated with specific navigation. Simultaneous arthroscopy also allows the correction of certain intra-articular defects in the same operation, and the precise evaluation of the cartilage's state.

Use of bone allograft in tibial plateau fractures.

To determine the behaviour of bone allografts in the treatment of tibial plateau fractures, 20 recipients of frozen bone allograft for a depressed tibial plateau fracture were studied. Incorporation of grafts took place in all cases, and no complication secondary to the allograft use has been detected. To avoid donor site morbidity associated with harvesting iliac crest, the use of frozen bone allograft is a good alternative in the treatment of depressed tibial plateau fractures.

[Image of pseudocapture caused by micro-dislodgment of the electrode in a VDD pacemaker]. / Imagen de seudocaptura por microdesplazamiento del electrodo en un marcapasos VDD.

The new AV sequential pacemakers have improved the suitability for the election of the best pacing mode for each patient. The complexity of the systems may mask some dysfunctions. In the presented case, a failure to capture due to micro-dislodgment, may have been missed in a simple pacemaker control, because of the combination of several factors: the presence of normal AV conduction at that moment, the concordance between the pacemaker stimulus and the conducted QRS complex and the similar morphology of the conducted and paced QRS complex.

[Mechanisms favoring and triggering atrial fibrillation]. / Mécanismes favorisant et déclenchant la fibrillation auriculaire.

Many experimental and clinical studies have demonstrated that it is possible to trigger atrial fibrillation (AF) by vagal stimulation which reduces and disperses the atrial refractory periods and decreases the threshold of fibrillation. In order to induce fibrillation, it is necessary to deliver a stimulation near to the refractory period. It has also been shown that, in these conditions, there is a delay in atrial conduction. A temporal relationship between the preceding diastole and the coupling interval increases atrial vulnerability and plays an equally important role. The decrease in the effective atrial refractory period, especially when the values are widely dispersed, and the delay in conduction predisposing to atrial reentry, may be considered to be the two most important electrophysiological mechanisms of AF. However, in order to maintain AF, the atrium must be dilated, especially when there is a concurrent cardiac disease. The presence of a shorter "wave length" of activation allowing multiple reentry circuits is an essential condition for sustaining AF. All conductions of induction and maintenance of AF may be observed without participation of S.N.A.. When no cause of AF (atrial pathology, etc.) is apparent, a short atrial refractory period with dispersion of its values and slowing of atrial conduction in presence of an extrastimulus are the probable inducing factors.

Atrial fibrillation in patients with an accessory pathway: importance of the conduction properties of the accessory pathway.

To investigate how the electrophysiologic properties of the accessory pathway affect the occurrence of atrial fibrillation in the Wolff-Parkinson-White syndrome, programmed stimulation data of 57 patients with overt pre-excitation and 33 patients with a concealed accessory pathway with documented circus movement tachycardia were reviewed. Atrial fibrillation had occurred spontaneously in 31 (54%) of the 57 patients with the Wolff-Parkinson-White syndrome and in 1 (3%) of the 33 with a concealed accessory pathway (p less than 0.001). Sustained atrial fibrillation was induced in 23 of 31 patients with the Wolff-Parkinson-White syndrome and spontaneous atrial fibrillation (Group A), in 7 of 26 patients with the Wolff-Parkinson-White syndrome without spontaneous atrial fibrillation (Group B) and in 5 of 33 patients with a concealed accessory pathway (Group C). The anterograde effective refractory period of the accessory pathway was shorter in Group A than in Group B (252 versus 297 ms, p less than 0.001). There were no differences among groups in PA interval, right to left atrium conduction time, cycle length of tachycardia and atrial and retrograde accessory pathway effective refractory period. Atrial fibrillation is more frequent in patients with the Wolff-Parkinson-White syndrome than in those with a concealed accessory pathway. Patients with overt pre-excitation and atrial fibrillation have a shorter anterograde accessory pathway refractory period. It seems therefore that the anterograde rather than the retrograde conduction properties of the accessory pathway are the critical determinants of atrial fibrillation in the Wolff-Parkinson-White syndrome.

Study of the evolution of masked bifascicular block.

Masked bifascicular block (MBB) (absent or minimal S in I and VL, high R in Vi and AQRS approximately -60 degrees) is a rare condition. We have found 16 such cases in the last 12 years, thirteen male and three female, mean age 70 +/- 9 years. The conventional electrocardiogram was tabulated and the clinical features and evolution of the patients were followed over 39.1 +/- 32 months. Ten patients required pacemakers, nine because of complete atrioventricular (AV) block or increase in the previous AV block. Seven patients died (follow-up 27.3 +/- 32 months), five from heart failure. This study shows: (1) MBB is a subgroup of patients with a high risk of advanced atrioventricular block; (2) a pacemaker implant does not significantly reduce the high mortality in this group because of the severity of the underlying disease; (3) these results should be evaluated in a larger series of patients in order to confirm our provisional results.

Interatrial conduction block and retrograde activation of the left atrium and paroxysmal supraventricular tachyarrhythmia.

We studied 16 patients with electrocardiographic evidence of advanced interatrial block and retrograde activation of the left atrium (P greater than or equal to 0.12 s, and diphasic (+/-) P waves in leads II, III, and VF). Eight patients had valvular heart disease, four had dilated cardiomyopathy and four had other forms of heart disease. Patients with valvular heart disease and cardiomyopathy were compared with a control group of 22 patients with similar clinical and echocardiographic characteristics, but without this type of interatrial block. Patients with advanced interatrial block and retrograde activation of the left atrium had a much higher incidence of paroxysmal supraventricular tachyarrhythmias (93.7%) during follow-up than did the control group, (27.7%) (P less than 0.001). Eleven of 16 patients (68.7%) with advanced interatrial block and retrograde activation of left atrium had atrial flutter (atypical in seven cases, typical in two cases, and with two or more morphologies in two cases). Six patients from the control group (27.7%) had sustained atrial tachyarrhythmias (five atrial fibrillation and one typical atrial flutter). The atrial tachyarrhythmias were due more to advanced interatrial block and retrograde activation of left atrium and frequent atrial extrasystoles than to left atrial enlargement, because the control group with a left atrium of the same size, but without advanced interatrial block and retrograde activation of left atrium and with less incidence of atrial extrasystoles, had a much lower incidence of paroxysmal tachycardia.

[Electrophysiologic characteristics of the transplanted heart]. / Características electrofisiológicas del corazón trasplantado.

The electrophysiologic characteristics of the denervated human heart were assessed in 20 cardiac transplants recipient from the Cardiology Department, at the Hospital of San Pablo, Barcelona, Spain. We studied the donor and the recipient sinus node function at rest and exercise test. Holter recording of 24 hours was performed in a few cases. At rest, in 14 patients the intrinsic heart rate of the donor atrium was slower when we used the technique of José. When we analyzed all the results we did not find statistical differences in the heart rate of either: the donor or the recipient atria (r = 0.58, p less than 0.01). However we observed a marked increase in heart rate of the donor with exercise test and normal activity (Holter), probably reflecting an increase in circulating catecholamines (exercise test: base-line 116 +/- 16 vs maximum exercise 140 +/- 10, p less than 0.001; Holter: minimal rate 64 +/- 9.66 vs maximal rate 112 +/- 23, p less than 0.001). We also describe the cardiac arrhythmias including two sudden deaths associated with ventricular tachyarrhythmias and in five patients sinus node disfunction in relation with episodes of acute rejection. We concluded that is important to perform a standard 12 lead electrocardiogram, exercise testing, Holter recording and electrophysiologic study as part of the ongoing routine evaluation of surviving cardiac transplant patients.