General: Células madre adipocíticas montadas en armazones de PRP

Adipose-derived stem cells incorporated into platelet-rich plasma improved bone regeneration and maturation in vivo
Ariadne Cristiane Cabral Cruz, Thiago Caon, Alvaro Menin, Rodrigo Granato, Fernanda Boabaid, Cláudia Maria Oliveira Simões
Dental Traumatology: 2014 October 21

BACKGROUND/AIM: Some cases of tooth loss related to dental trauma require bone-grafting procedures to improve the aesthetics before prosthetic rehabilitation or to enable the installation of dental implants. Bone regeneration is often a challenge and could be largely improved by mesenchymal stem cells therapy. However, the appropriate scaffold for these cells still a problem. This study evaluated the in vivo effect of human adipose-derived stem cells incorporated into autogenous platelet-rich plasma in bone regeneration and maturation.

MATERIAL AND METHODS: Adipose-derived stem cells were isolated from lipoaspirate tissues and used at passage 4. Immunophenotyping and multilineage differentiation of cells were performed and mesenchymal stem cells characteristics confirmed. Bicortical bone defects (10 mm diameter) were created in the tibia of six beagle dogs to evaluate the effect of adipose-derived stem cells incorporated into platelet-rich plasma scaffolds, platelet-rich plasma alone, autogenous bone grafts, and clot. Samples were removed 6 weeks postsurgeries and analyzed by quantification of primary and secondary bone formation and granulation tissue.

RESULTS: Adipose-derived stem cells incorporated into platelet-rich plasma scaffolds promoted the highest bone formation (primary + secondary bone) (P < 0.001), the highest bone maturation (secondary bone) (P < 0.001), and the lowest amount of granulation tissue (P < 0.001).

CONCLUSIONS: Adipose-derived stem cells incorporated into platelet-rich plasma scaffolds promote more bone formation and maturation, and less granulation tissue in bone defects created in canine tibia. Therefore, platelet-rich plasma can be considered as a candidate scaffold for adipose-derived stem cells to promote bone regeneration.

Tobillo/Ankle/Knöchel/Cheville: Microfracturas por artroscopia en jóvenes con lesiones pequeñas

Functional and MRI Outcomes After Arthroscopic Microfracture for Treatment of Osteochondral Lesions of the Distal Tibial Plafond
Keir A. Ross, Charles P. Hannon, Timothy W. Deyer, Niall A. Smyth, MaCalus Hogan, Huong T. Do,  John G. Kennedy,
J Bone Joint Surg Am, 2014 Oct 15;96(20):1708-1715.

Abstract

Background: Osteochondral lesions of the distal tibial plafond are uncommon compared with talar lesions. The objective of this study was to assess functional and magnetic resonance imaging (MRI) outcomes following microfracture for tibial osteochondral lesions.

Methods: Thirty-one tibial osteochondral lesions in thirty-one ankles underwent arthroscopic microfracture. The Foot and Ankle Outcome Score (FAOS) and Short Form-12 (SF-12) general health questionnaire were used to obtain patient-reported functional outcome scores preoperatively and postoperatively. MRI scans were assessed postoperatively with use of the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score for twenty-three ankles.

Results: The average age was thirty-seven years (range, fifteen to sixty-eight years), and the average lesion area was 38 mm2 (range, 7.1 to 113 mm2). Twelve ankles had a kissing lesion on the opposing surface of the talus, and two ankles had a concomitant osteochondral lesion elsewhere on the talus. FAOS and SF-12 scores were significantly improved (p < 0.01) at the time of follow-up, at an average of forty-four months. The average postoperative MOCART score was 69.4 (range, 10 to 95), with a lower score in the ankles with kissing lesions (62.8) than in the ankles with an isolated lesion (73.6). Increasing age negatively impacted improvement in SF-12 (p < 0.01) and MOCART (p = 0.04) scores. Increasing lesion area was negatively correlated with MOCART scores (p = 0.04) but was not associated with FAOS or SF-12 scores. Lesion location and the presence of kissing lesions showed no association with functional or MRI outcomes.

Conclusions: Arthroscopic microfracture provided functional improvements, but the optimal treatment strategy for tibial osteochondral lesions remains unclear. The repair tissue assessed on MRI was inferior to normal hyaline cartilage. The MRI outcomes appeared to deteriorate with increasing lesion area, and both functional and MRI outcomes appeared to deteriorate with increasing age.

Level of Evidence: Therapeutic Level IV

Cadera/Hip/Hüfte/Hanche: Vástagos cortos con mucho cuidado

Short Bone-Conserving Stems in Cementless Hip Arthroplasty
Harpal S. Khanuja, Samik Banerjee, Deepak Jain,  Robert Pivec,  Michael A. Mont
J Bone Joint Surg Am, 2014 Oct 15; 96(20):1742-1752

Abstract

➤ Short bone-conserving femoral stems in total hip arthroplasty were designed to preserve proximal bone stock.
➤ Given the distinct fixation principles and location of loading among these bone-conserving stems, a classification system is essential to compare clinical outcomes.
➤ Due to the low quality of currently available evidence, only a weak recommendation can be provided for clinical usage of certain stem designs, while some other designs cannot be recommended at this time.
➤ A high prevalence of stem malalignment, incorrect sizing, subsidence, and intraoperative fractures has been reported in a subset of these short stem designs.
➤ Stronger evidence, including prospective multicenter randomized trials comparing standard stems with these newer designs, is necessary before widespread use can be recommended.

General: No se infectan las protesis por infiltrar antes la articulación

Do Intra-Articular Steroid Injections Increase Infection Rates in Subsequent Arthroplasty? A Systematic Review and Meta-Analysis of Comparative Studies

Charalambos P. Charalambous, Apostolos D. Prodromidis, Tariq A. Kwaees

J of Arthroplasty Published Online: August 02, 2014

Abstract

Intra-articular steroid injections are widely used in joint arthritis. The safety of such injections has been questioned as they may increase infection rates in subsequent arthroplasty. We carried out a meta-analysis of studies examining the relation between intra-articular steroid injections and infection rates in subsequent joint arthroplasty. A literature search was undertaken. Eight studies looking at hip and knee arthroplasties were analyzed. Meta-analysis showed that steroid injection had no significant effect on either deep (risk ratio = 1.87; 95% CI 0.80–4.35; P = 0.15) or superficial infection rates (risk ratio = 1.75; 95% CI 0.76–4.04; P = 0.19) of subsequent arthroplasty. Further large cohort studies would be of value in further examining whether steroid injections close to the time of arthroplasty are safe.

Hombro/Shoulder/Schulter/Épaule: anestésicos citotóxicos para el hombro

Cytotoxic Effects of Ropivacaine, Bupivacaine, and Lidocaine on Rotator Cuff Tenofibroblasts.
Sung CM, Hah YS, Kim JS, Nam JB, Kim RJ, Lee SJ, Park HB.
Am J Sports Med. 2014 Oct 8 [Epub ahead of print]

Abstract

BACKGROUND:
Concern has recently arisen over the safety of local anesthetics used on human tissues.

HYPOTHESIS:
Aminoamide local anesthetics have cytotoxic effects on human rotator cuff tenofibroblasts.

STUDY DESIGN:
Controlled laboratory study.

METHODS:
Cultured human rotator cuff tenofibroblasts were divided into control, phosphate buffered saline (PBS), and local anesthetic study groups; the PBS study group was further subdivided by pH level (pH 7.4, 6.0, and 4.4). The 6 local anesthetic subgroups (0.2% and 0.75% ropivacaine, 0.25% and 0.5% bupivacaine, and 1% and 2% lidocaine) were also studied at 10% dilutions of their original concentrations. Exposure times were 5, 10, 20, 40, or 60 minutes for the higher concentrations and 2, 6, 12, 24, 48, or 72 hours for the lower concentrations. Cell viability was evaluated through live, apoptotic, and necrotic cell rates using the annexin V-propidium iodide double-staining method. Intracellular reactive oxygen species (ROS) and the activity of mitogen-activated protein kinases (MAPKs) and caspase-3/7 were investigated.

RESULTS:
The control and PBS groups showed no significant differences in cell viability (P > .999). In the local anesthetic study groups, cell viability decreased significantly with increases in anesthetic concentrations (P < .001) and exposure times (P < .001), with the exception of the lidocaine subgroups, where this effect was masked by the very high cytotoxicity of even low concentrations. Among the studied local anesthetic subgroups, 0.2% ropivacaine was the least toxic. The levels of intracellular ROS of each local anesthetic subgroup also increased significantly (P < .05). The studied local anesthetics showed increases in the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38 as well as in levels of caspase-3/7 activity (P < .001).

CONCLUSION:
The cytotoxicity of the anesthetics studied to tenofibroblasts is dependent on exposure time and concentration. Of the evaluated anesthetics, ropivacaine is the least toxic in the clinically used concentration. The studied anesthetics induce tenofibroblast cell death, mediated by the increased production of ROS, by the increased activation of ERK1/2, JNK, and p38 and by the activation of caspase-3/7.

CLINICAL RELEVANCE:
This study identified the cytotoxic mechanisms of aminoamide local anesthetics acting on rotator cuff tenofibroblasts. The greatest margin of safety was found in lower anesthetic concentrations in general and more specifically in the use of ropivacaine.


KEYWORDS:

Hombro/Shoulder/Schulter/Èpaule: donde pones el ojo sueles poner la aguja

Accuracy of Palpation-Directed Intra-articular Glenohumeral Injection Confirmed by Magnetic Resonance Arthrography
Scott E Powell, Shane M Davis, Emily H Lee, Robert K Lee, Ryan M Sung, Claire McGroder, Shalen Kouk, Christopher S Lee
Arthroscopy: the Journal of Arthroscopic & related Surgery 2014 October 8 [Epub ahead of print]

PURPOSE: The aim of this study was to determine the accuracy of anatomic palpation-directed injections in the office setting.

METHODS: Two hundred twenty-six shoulders in 208 patients were studied using a 0.2-Tesla extremity scanner after the injection of gadolinium-diethylene triamine pentaacetic acid-saline. All patients were injected in a sterile fashion by a single board-certified shoulder surgeon using an anterior approach by palpating the rotator interval anterior to the acromioclavicular joint and angling the needle 45° lateral and 45° caudad. All injections, successful or otherwise, were single injections. Magnetic resonance (MR) arthrograms were retrospectively read by 2 musculoskeletal fellowship-trained, board certified radiologists to determine whether the injection was in the glenohumeral joint.

RESULTS: Two hundred one of the 226 injections were successful (88.9%). Of the 25 unsuccessful injections, the contrast material extravasated out of the capsule in 5 cases and into the subscapularis tendon in 10 cases. The contrast material was injected into the subacromial space in 9 cases, into the rotator interval fat in 9 cases, and into extracapsular tissue in 6 cases. There was insufficient volume of contrast material in 10 cases. The accuracy rate was 88.9%. There were no complications.

CONCLUSIONS: The palpation-directed rotator interval anterior approach technique for intra-articular glenohumeral MR arthrogram injections performed by a single surgeon was 88.9% accurate.

LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Rodilla/Knee/Knie/Genou: ¿Un remedio milagroso para la rodilla lesionada?

Platelet Rich Plasma and Knee Surgery
Mikel Sánchez, Diego Delgado, Pello Sánchez, Nicolás Fiz, Juan Azofra, Gorka Orive, Eduardo Anitua, Sabino Padilla
Biomed Res Int. 2014; 2014: 890630.
Published online Sep 2, 2014

Abstract

In orthopaedic surgery and sports medicine, the knee joint has traditionally been considered the workhorse. The reconstruction of every damaged element in this joint is crucial in achieving the surgeon's goal to restore the knee function and prevent degeneration towards osteoarthritis. In the last fifteen years, the field of regenerative medicine is witnessing a boost of autologous blood-derived platelet rich plasma products (PRPs) application to effectively mimic and accelerate the tissue healing process. The scientific rationale behind PRPs is the delivery of growth factors, cytokines, and adhesive proteins present in platelets and plasma, as well as other biologically active proteins conveyed by the plasma such as fibrinogen, prothrombin, and fibronectin; with this biological engineering approach, new perspectives in knee surgery were opened. This work describes the use of PRP to construct and repair every single anatomical structure involved in knee surgery, detailing the process conducted in ligament, meniscal, and chondral surgery.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4167644/

Cadera/Hip/Hüfte/Hanche: Cerámica contra polietileno: ¿combinación aceptable?

The case for ceramic-on-polyethylene as the preferred bearing for a young adult hip replacement

David J.W. Cash, Vikas Khanduja

Hip Int 2014; 24(5): 421 - 427

Article Type: REVIEW

Abstract

The optimum choice of bearing surfaces in total hip arthroplasty, particularly in the younger and more active patient, remains controversial. Despite several studies demonstrating good long-term results for the metal-on-polyethylene articulation, there has been a recent vogue towards the utilisation of hard-on-hard bearings for younger patients due, in part, to concerns regarding polyethylene induced osteolysis. However, well-documented complications concerning metal-on-metal bearings and the risk of fracture in ceramic-on-ceramic bearings have raised concerns regarding the principle of the hard-on-hard bearing in the active patient. With recent technological advancements in the manufacture of both polyethylene and alumina ceramics, the in vitro properties of each material with regards to strength and toughness have been significantly improved. In addition, ceramic femoral heads have consistently been shown to produce less in vivo polyethylene wear than similar sized metal heads. This paper aims to critically review the biomechanical, in vivo and clinical studies related to the use of the ceramic on polyethylene bearing, and highlights its potential use as the preferred bearing for a young adult hip replacement.

Rodilla/Knee/Knie/Genou: Abrir o cerrar la osteotomía de tibia; hay diferencias

Comparison of Closing-Wedge and Opening-Wedge High Tibial Osteotomy for Medial Compartment Osteoarthritis of the Knee: A Randomized Controlled Trial with a Six-Year Follow-up.

Duivenvoorden T, Brouwer RW, Baan A, Bos PK, Reijman M, Bierma-Zeinstra SM, Verhaar JA.
J Bone Joint Surg Am. 2014 Sep 3;96(17)

Abstract

BACKGROUND:

Varus deformity increases the risk of progression of medial compartment knee osteoarthritis. The aim of this study was to investigate the clinical and radiographic mid-term results of closing-wedge and opening-wedge high tibial osteotomy when used to treat this condition.

METHODS:

From January 2001 to April 2004, ninety-two patients were randomized to receive either a closing-wedge or an opening-wedge high tibial osteotomy. The clinical outcome and radiographic results were examined preoperatively; at one year; and, for the present study, at six years postoperatively. The outcomes that we reviewed included maintenance of the achieved correction, progression of osteoarthritis (based on the Kellgren and Lawrence classification), severity of pain (as assessed on a visual analog scale [VAS]), knee function (as measured with the Hospital for Special Surgery [HSS] score and Knee injury and Osteoarthritis Outcome Score [KOOS]), walking distance, complications, and survival with conversion to a total knee arthroplasty as the end point. The results were analyzed on the basis of the intention-to-treat principle.

RESULTS:

Six years postoperatively, the mean hip-knee-ankle (HKA) angle (and standard deviation) was 3.2° ± 4.1° of valgus after a closing-wedge high tibial osteotomy and 1.3° ± 5.0° of valgus after an opening-wedge high tibial osteotomy (p = 0.343). In both groups, the six-year postoperative HKA angles did not differ from the respective one-year postoperative angles. No difference in the severity of pain or in knee function was found between the two groups. Four complications (9%) occurred in the closing-wedge group and seventeen (38%), in the opening-wedge group. Ten (22%) of the patients in the closing-wedge group and three (8%) in the opening-wedge group needed conversion to a total knee arthroplasty within the six-year period (p = 0.05). The difference in the percentage of cases with conversion to total knee arthroplasty was 14% (95% confidence interval [CI] = 21.7 to 0.2).

CONCLUSIONS:

In the group of patients without conversion to a total knee arthroplasty, there was no difference between the high tibial closing-wedge and opening-wedge osteotomies in terms of clinical outcomes or radiographic alignment at six years postoperatively. Opening-wedge osteotomy was associated with more complications, but closing-wedge osteotomy was associated with more early conversions to total knee arthroplasty.

LEVEL OF EVIDENCE:

Therapeutic Level I

Pie /Foot/Fuss/Tarte: Osteotomías del primer metacarpiano para el juanete

Proximal opening wedge osteotomy with wedge-plate fixation compared with proximal chevron osteotomy for the treatment of hallux valgus: a prospective, randomized study
Mark Glazebrook, Peter Copithorne, Gordon Boyd, Timothy Daniels, Karl-André Lalonde, Patricia Francis, Michael Hickey
Journal of Bone and Joint Surgery. American Volume 2014 October 1, 96 (19): 1585-92

BACKGROUND:
Hallux valgus with an increased intermetatarsal angle is usually treated with a proximal metatarsal osteotomy. The proximal chevron osteotomy is commonly used but is technically difficult. This study compares the proximal opening wedge osteotomy of the first metatarsal with the proximal chevron osteotomy for the treatment of hallux valgus with an increased intermetatarsal angle.

METHODS:
This prospective, randomized multicenter (three-center) study was based on the clinical outcome scores of the Short Form-36, the American Orthopaedic Foot & Ankle Society forefoot questionnaire, and the visual analog scale for pain, activity, and patient satisfaction. Subjects were assessed prior to surgery and at three, six, and twelve months postoperatively. Surgeon preference was evaluated based on questionnaires and the operative times required for each procedure.

RESULTS:
No significant differences were found for any of the patients' clinical outcome measurements between the two procedures. The proximal opening wedge osteotomy was found to lengthen, and the proximal chevron osteotomy was found to shorten, the first metatarsal. The intermetatarsal angles improved (decreased) significantly, from 14.8° ± 3.2° to 9.1° ± 2.9 (mean and standard deviation) after a proximal opening wedge osteotomy and from 14.6° ± 3.9° to 11.3° ± 4.0° after a proximal chevron osteotomy (p < 0.05 for both). Operative time required for performing a proximal opening wedge osteotomy is similar to that required for performing a proximal chevron osteotomy (mean and standard deviation, 67.1 ± 16.5 minutes compared with 69.9 ± 18.6 minutes; p = 0.510).

CONCLUSIONS:
Opening wedge and proximal chevron osteotomies have comparable radiographic outcomes and comparable clinical outcomes for pain, satisfaction, and function. The proximal opening wedge osteotomy lengthens, and the proximal chevron osteotomy shortens, the first metatarsal. The proximal opening wedge osteotomy was subjectively less technically demanding and was preferred by the orthopaedic surgeons in this study.

LEVEL OF EVIDENCE: Therapeutic Level I

Trauma: Abordaje modificado de Stoppa para las fracturas acetabulares

Treatment of acetabulum fractures through the modified stoppa approach: strategies and outcomes
Mark J Isaacson, Benjamin C Taylor, Bruce G French, Attila Poka
Clinical Orthopaedics and related Research 2014, 472 (11): 3345-52

BACKGROUND:
Since the original description by Letournel in 1961, the ilioinguinal approach has remained the predominant approach for anterior acetabular fixation. However, modifications of the original abdominal approach described by Stoppa have made another option available for reduction and fixation of pelvic and acetabular fractures.

QUESTIONS/PURPOSES:
We evaluated our results in patients with acetabulum fractures with the modified Stoppa approach in terms of (1) hip function as measured by the Merle d'Aubigne hip score; (2) complications; and (3) quality of fracture reduction and percentage of fractures that united.

METHODS:
Between September 2008 and August 2012, 289 patients with acetabular fractures were treated at our Level I trauma center. Twelve percent (36 of 289) of patients were treated operatively using the modified Stoppa approach. Ninety-seven percent (35 of 36) of our patients had fracture patterns involving displacement of the posterior column. Six (17%) were converted early to a total hip arthroplasty, and 14 (39%) were lost to final followup, leaving 22 of 36 for subjective clinical outcome analysis at a mean of 32 months (range, 9-59 months). Our general indications for this approach during the period in question were fractures of the anterior column and anterior wall, anterior column with posterior hemitransverse fractures, both column fractures, transverse fractures, and T-type fractures. Followup included regularly scheduled office visits with radiographs (AP pelvis, Judet views) that were graded by the treating surgeon and by the authors of this study (MJI, BCT) and patient outcome surveys.

RESULTS:
Merle d'Aubigne hip scores were very good in 55% (12 of 22), good in 9% (two of 22), medium in 18% (four of 22), fair in 5% (one of 22), and poor in 14% (three of 22), and 70% (23 of 33) of patients were able to ambulate without any assistive devices. Complications included one superficial infection and three deep infections, two patients with temporary lateral thigh numbness, no obturator nerve palsies, and one inguinal hernia. Three deaths in the cohort were seen in followup as a result of unrelated causes. Radiographic grading of fracture reductions after surgery revealed that 27 (75%) were anatomic, six (17%) were satisfactory, and three (8%) were unsatisfactory. A total of 94% of the fractures united.

CONCLUSIONS:
In agreement with prior published data, our results show good functional outcomes with minimal complications using the modified Stoppa approach for a variety of acetabular fractures. Our results highlight the difficulty but feasibility in treating posterior column displacement through an anterior approach. Consideration for dual approaches with posterior column involvement may be warranted to optimize fracture reduction and functional outcomes.

LEVEL OF EVIDENCE: Level IV, therapeutic study

Cadera/Hip/Hüfte/Hanche: Tras la artroscopia de cadera, habría que cerrar bien la cápsula

Anterior hip dislocation 5 months after hip arthroscopy
Daniel C Austin, John G Horneff, John D Kelly
Arthroscopy: the Journal of Arthroscopic & related Surgery 2014, 30 (10): 1380-2

Hip dislocation subsequent to hip arthroscopy is a rare complication. We report on a case of low-energy anterior hip dislocation that occurred 5 months after hip arthroscopy, a period notably longer than any previously reported event. The patient was a track and field athlete who presented and received treatment for a labral tear and cam lesion. The athlete then dislocated her hip postoperatively during competitive jumping, a motion that requires significant hip flexion and extension. The most likely cause of the anterior dislocation was failure to close the capsule at the completion of surgery, lending credibility to recent trends in the literature suggesting routine capsular closure. We believe that a partial psoas release also contributed to dynamic hip instability because of increased femoral anteversion in this patient. This case suggests that hip capsule closure should be considered at the completion of every procedure and that a psoas release should be avoided in patients with significant anteversion. Furthermore, the biomechanics of competitive jumping may make these athletes more prone to dislocation and require more conservative return-to-sport recommendations.

Cadera/Hip/Hüfte/Hanche: Bloquear el dolor de la cadera con necrosis avascular

Bloqueo intraarticular y de ramas sensoriales del nervios obturador y femoral en cuadro de osteonecrosis y artrosis de la cabeza femoral
M. Cortiñas-Sáenz, G. Salmerón-Vélez, I.A. Holgado-Macho
Rev Esp Cir Ortop Traumatol. 2014; 58(5):319-342

RESUMEN
La inervación sensitiva de la articulación de la cadera es compleja. El bloqueo intraarticular y de las ramas sensitivas de los nervios obturador y femoral es eficaz para tratar el dolor producido por diversas enfermedades de cadera, y pudiera ser una opción a considerar en determinadas circunstancias. Estas circunstancias pueden ser alto riesgo quirúrgico-anestésico por el estado basal del paciente o la existencia de sobrepeso importante, en otras ocasiones el médico traumatólogo considera que es mejor retrasar la artroplastia, al menos durante algún tiempo.

General: Proteger las manos y los ojos del traumatólogo, incluso corazón y cerebro

Radiation safety in orthopedic operating theaters: What is the current situation?
Radioprotección en quirófanos de traumatología: ¿en qué situación estamos?
M. Torres-Torres, J. Mingo-Robinet, M. Moreno Barrero, J.Á. Rivas Laso, I. Burón Álvarez, M. González Salvador
Rev Esp Cir Ortop Traumatol 2014;58(5):309-313

Abstract

Objective
To analyze the exposure of two Orthopedic Surgeons to ionizing radiations in their daily work, and to review the main national and international recommendations on this subject.

Material and methods
A retrospective study was conducted on the surgical treatments that use fluoroscopy performed by two orthopedic surgeons during a one year period. An evaluation was made of the radiation received, based on measurements of the processes published in the bibliography section. A literature review of international recommendations and regulations is also presented.

Results
The radiation received by the two orthopedic surgeons during one year did not exceed the limits of present-day legislation or the new European and international recommendations. The exposure was asymmetrical, with the hands being the most radiated part. The new recommendations reduce the permitted level of radiation on eyes.

Discussion
The evaluation of the radiation received demonstrates the need for radiation protection, paying particular attention to the hands and eyes. Good knowledge of operating a fluoroscope and radiation safety measures are also essential.

Nivel de evidencia IV

Cadera/Hip/Hüfte/ Hanche: Intoxicación metálica, por los pelos

Detection of metal ions in hair after metal–metal hip arthroplasty
Detección de iones metálicos en cabello tras artroplastia de cadera metal-metal
D. Hernandez-Vaquero, M. Rodríguez de la Flor, J.M. Fernandez-Carreira, C. Sariego-Muñiz
Rev Esp Cir Ortop Traumatol. 2014;58(5):267-273

Abstract

Objective
There is an increase in the levels of metals in the serum and urine after the implantation of some models of metal–metal hip prosthesis. It has recently been demonstrated that there is an association between these levels and the levels found in hair. The aim of this study is to determine the presence of metals in hair, and to find out whether these change over time or with the removal of the implant.

Materials and methods
The levels of chromium, cobalt and molybdenum were determined in the hair of 45 patients at 3, 4, 5, and 6 years after a hip surface replacement. The mean age was 57.5 years, and two were female. Further surgery was required to remove the replacement and implant a new model with metal–polyethylene friction in 11 patients, 5 of them due to metallosis and a periarticular cyst.

Results
The mean levels of metals in hair were chromium 163.27 ppm, cobalt 61.98 ppm, and molybdenum 31.36 ppm, much higher than the levels found in the general population. A decrease in the levels of chromium (43.8%), molybdenum (51.1%), and cobalt (91.1%) was observed at one year in the patients who had further surgery to remove the prosthesis.

Conclusions
High concentrations of metals in the hair are observed in hip replacements with metal–metal friction, which decrease when that implant is removed. The determination of metal ions in hair could be a good marker of the metal poisoning that occurs in these arthroplasty models.


Nivel de evidencia 3

Hombro/Shoulder/Schülter/Épaule: parálisis en la silla de playa

Lateral femoral cutaneous nerve palsy following shoulder surgery in the beach chair position: a report of 4 cases.
Satin AM, DePalma AA, Cuellar J, Gruson KI1.
Am J Orthop (Belle Mead NJ). 2014 Sep;43(9)

Abstract

Neuropathy of the lateral femoral cutaneous nerve can present as pain, decreased sensation, and/or burning or tingling on the anterolateral thigh. We present 4 cases of lateral femoral cutaneous nerve palsy following shoulder surgery in the beach chair position, all of which occurred in obese patients. This complication, to our knowledge, has never been reported in conjunction with the beach chair position. We believe that the neurapraxia was due to external compression by the patients' abdominal pannus. Full resolution of symptoms can be expected within 6 months following conservative management. A preoperative discussion regarding this complication should occur with obese patients undergoing shoulder surgery in the beach chair position.