Cadera/Hip/Hüfte/Hanche: No sirve la puntuación WOMAC

Can the pre-operative Western Ontario and McMaster score predict patient satisfaction following total hip arthroplasty? 

Rogers, B. A., Alolabi, B., Carrothers, A. D., Kreder, H. J., Jenkinson, R. J.

Bone Joint J 2015;97-B:150–3.

In this study we evaluated whether pre-operative Western Ontario and McMaster Universities (WOMAC) osteoarthritis scores can predict satisfaction following total hip arthroplasty (THA).

Prospective data for a cohort of patients undergoing THA from two large academic centres were collected, and pre-operative and one-year post-operative WOMAC scores and a 25-point satisfaction questionnaire were obtained for 446 patients. Satisfaction scores were dichotomised into either improvement or deterioration. Scatter plots and Spearman’s rank correlation coefficient were used to describe the association between pre-operative WOMAC and one-year post-operative WOMAC scores and patient satisfaction. Satisfaction was compared using receiver operating characteristic (ROC) analysis against pre-operative, post-operative and WOMAC scores.

We found no relationship between pre-operative WOMAC scores and one-year post-operative WOMAC or satisfaction scores, with Spearman’s rank correlation coefficients of 0.16 and –0.05, respectively. The ROC analysis showed areas under the curve (AUC) of 0.54 (pre-operative WOMAC), 0.67 (post-operative WOMAC) and 0.43 ( WOMAC), respectively, for an improvement in satisfaction.

We conclude that the pre-operative WOMAC score does not predict the post-operative WOMAC score or patient satisfaction after THA, and that WOMAC scores can therefore not be used to prioritise patient care.

 

Rodilla/Knne: Van peor las PTR en enfermos con lesiones menos graves

Chronic non-orthopedic conditions more common in patients with less severe degenerative changes that have elected to undergo total knee arthroplasty

Cale A. Jacobs, Christian P. Christensen, Tharun Karthikeyan
J Arthroplasty: Published Online: February 06, 2015

DOI: http://dx.doi.org/10.1016/j.arth.2015.01.051

The purpose of this study was to determine whether the prevalence of chronic non-orthopedic conditions that may play a role in an abnormal pain response differ between patients based on the severity of degenerative changes at the time of surgery.

Of 1,020 OA knees that had undergone primary TKA with a minimum 2 year follow-up, we identified 117 (11.5%) that had less severe degenerative changes. The prevalence of dissatisfaction was significantly greater in less severe group compared to those with moderate or severe changes (18.8% vs. 9.3%, p = .003). Chronic non-orthopedic conditions were significantly more prevalent in the less severe group with 41.9% reporting depression/anxiety, 30.8% with fibromyalgia or low back pathology, and 12.8% with a prior traumatic brain injury or stroke.

General: Entrenamiento virtual para hacerlo bien

Fundamental arthroscopic skill differentiation with virtual reality simulation

Rose K, Pedowitz R.

Arthroscopy. 2015 Feb;31(2):299-305
doi: 10.1016/j.arthro.2014.08.016

Abstract

PURPOSE:
The purpose of this study was to investigate the use and validity of virtual reality modules as part of the educational approach to mastering arthroscopy in a safe environment by assessing the ability to distinguish between experience levels. Additionally, the study aimed to evaluate whether experts have greater ambidexterity than do novices.

METHODS:
Three virtual reality modules (Swemac/Augmented Reality Systems, Linkoping, Sweden) were created to test fundamental arthroscopic skills. Thirty participants-10 experts consisting of faculty, 10 intermediate participants consisting of orthopaedic residents, and 10 novices consisting of medical students-performed each exercise. Steady and Telescope was designed to train centering and image stability. Steady and Probe was designed to train basic triangulation. Track and Moving Target was designed to train coordinated motions of arthroscope and probe. Metrics reflecting speed, accuracy, and efficiency of motion were used to measure construct validity.

RESULTS:
Steady and Probe and Track a Moving Target both exhibited construct validity, with better performance by experts and intermediate participants than by novices (P < .05), whereas Steady and Telescope did not show validity. There was an overall trend toward better ambidexterity as a function of greater surgical experience, with experts consistently more proficient than novices throughout all 3 modules.

CONCLUSIONS:
This study represents a new way to assess basic arthroscopy skills using virtual reality modules developed through task deconstruction. Participants with the most arthroscopic experience performed better and were more consistent than novices on all 3 virtual reality modules. Greater arthroscopic experience correlates with more symmetry of ambidextrous performance. However, further adjustment of the modules may better simulate fundamental arthroscopic skills and discriminate between experience levels.

CLINICAL RELEVANCE:
Arthroscopy training is a critical element of orthopaedic surgery resident training. Developing techniques to safely and effectively train these skills is critical for patient safety and resident education.

Ciencia/Science: ¡Un glioma de tanto hablar por el móvil!

Mobile phone and cordless phone use and the risk for glioma – Analysis of pooled case-control studies in Sweden, 1997–2003 and 2007–2009

Lennart Hardell, Michael Carlberg

Pathophysiology

Available online 29 October 2014, doi:10.1016/j.pathophys.2014.10.001

In Press

Abstract

We made a pooled analysis of two case-control studies on malignant brain tumours with patients diagnosed during 1997–2003 and 2007–2009.

They were aged 20–80 years and 18–75 years, respectively, at the time of diagnosis. Only cases with histopathological verification of the tumour were included. Population-based controls, matched on age and gender, were used. Exposures were assessed by questionnaire. The whole reference group was used in the unconditional regression analysis adjusted for gender, age, year of diagnosis, and socio-economic index.

In total, 1498 (89%) cases and 3530 (87%) controls participated. Mobile phone use increased the risk of glioma, OR = 1.3, 95% CI = 1.1–1.6 overall, increasing to OR = 3.0, 95% CI = 1.7–5.2 in the >25 year latency group. Use of cordless phones increased the risk to OR = 1.4, 95% CI = 1.1–1.7, with highest risk in the >15–20 years latency group yielding OR = 1.7, 95% CI = 1.1–2.5. The OR increased statistically significant both per 100 h of cumulative use, and per year of latency for mobile and cordless phone use. Highest ORs overall were found for ipsilateral mobile or cordless phone use, OR = 1.8, 95% CI = 1.4–2.2 and OR = 1.7, 95% CI = 1.3–2.1, respectively.

The highest risk was found for glioma in the temporal lobe. First use of mobile or cordless phone before the age of 20 gave higher OR for glioma than in later age groups.

Keywords

Ipsilateral25 years latencyTime since first exposureGliomaWireless phones

Rodilla/Knee: Ahorrar reinfusión de sangre con tranexámico

Effect of a Single Injection of Tranexamic Acid on Blood Loss after Primary Hybrid TKA

Yoshinori Ishii, Hideo Noguchi, Junko Sato, Chiduru Tsuchiya, Shin-ichi Toyabe

The Knee
Available online 17 January 2015

Background
Control of perioperative blood loss is important in total knee arthroplasty (TKA), especially cementless or hybrid TKA. There is increasing interest in the use of tranexamic acid (TXA) for this purpose; however, studies to date have mainly evaluated the effects of various TXA administration regimens on patients who underwent cemented TKA. We sought to determine (1) whether administration of TXA reduces blood loss after hybrid TKA, and (2) whether an autologous blood reinfusion system is necessary in TKA patients who are treated with TXA.

Methods
Ninety-five patients (100 knees) who underwent hybrid primary TKA (cemented tibia, uncemented femur) were included in this study. The initial 50 knees were treated without TXA and the following 50 were treated with TXA. Intravenous TXA (1000mg) was administered shortly before deflation of the tourniquet. All continuous variables are expressed as median values.

Results
Total volumes of blood lost at postoperative 1day were 590ml and 150ml and autotransfusion of collected blood was performed in 88 % and 16% of patients in the without and with TXA groups, respectively. A median volume of 400ml of collected blood was returned to the patients in the without TXA group, and 0ml to the patients in the with TXA group. The calculated volumes of blood lost were 761ml and 683ml (p=0.2250), respectively.

Conclusions
One intravenous injection of 1000mg TXA may help to control postoperative blood loss and reduce the need for postoperative autologous blood reinfusion after hybrid TKA.

Levels of evidence: Level II. 

Rodilla/Knee: Se supone que deberíamos avanzar

Are outcomes after total knee arthroplasty worsening over time? A time-trends study of activity limitation and pain outcomes

Singh JA, Lewallen DG

BMC Musculoskelet Disord 2014.:440.

Abstract

BACKGROUND

To examine whether function and pain outcomes of patients undergoing primary total knee arthroplasty (TKA) are changing over time.

METHODS

The Mayo Clinic Total Joint Registry provided data for time-trends in preoperative and 2-year post-operative activity limitation and pain in primary TKA patients from 1993-2005. We used chi-square test and analysis for variance, as appropriate. Multivariable-adjusted analyses were done using logistic regression.

RESULTS

In a cohort of 7,229 patients who underwent primary TKA during 1993-2005, mean age was 68.4 years (standard deviation (SD), 9.8), mean BMI was 31.1 (SD, 6.0) and 55% were women. Crude estimates showed that preoperative moderate-severe overall limitation were seen in 7.3% fewer patients and preoperative moderate-severe pain in 2.7% more patients in 2002-05, compared to 1992-95 (p < 0.001 for both). At 2-years, crude estimates indicated that compared to 1992-95, moderate-severe post-TKA overall limitation was seen in 4.7% more patients and moderate-severe post-TKA pain in 3.6% more patients in 2002-05, both statistically significant (p ≤ 0.018) and clinically meaningful. In multivariable-adjusted analyses that adjusted for age, sex, anxiety, depression, Deyo-Charlson index, body mass index and preoperative pain/limitation, patients had worse outcomes 2-year post-TKA in 2002-2005 compared to 1993-95 with an odds ratio (95% confidence interval (CI); p-value) of 1.34 (95% CI: 1.02, 1.76, p = 0.037) for moderate-severe activity limitation and 1.79 (95% CI: 1.17, 2.75, p = 0.007) for moderate-severe pain.

CONCLUSION

Patient-reported function and pain outcomes after primary TKA have worsened over the study period 1993-95 to 2002-05. This time-trend is independent of changes in preoperative pain/limitation and certain patient characteristics.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4301928/pdf/

Hombro/Shoulder: se gana igual, reparando el manguito a los 50 y a los 70

Comparison of Functional Gains After Arthroscopic Rotator Cuff Repair in Patients Over 70 Years of Age Versus Patients Under 50 Years of Age: A Prospective Multicenter Study
Constantina Moraiti, Pablo Valle, Ali Maqdes, Omar Boughebri, Chourky Dib, Giannis Giakas, B.Sc., Jean Kany, Kamil Elkholti, Jérôme Garret, Denis Katz, Franck Marie Leclère, Philippe Valenti, M.D.correspondenceemail
Received: July 7, 2013; Accepted: August 26, 2014; Published Online: November 11, 2014
Arthroscopy: The Journal of Arthroscopy and Related Surgery
February 2015Volume 31, Issue 2, Pages 184–190
Purpose
To assess rotator cuff rupture characteristics and evaluate healing and the functional outcome after arthroscopic repair in patients older than 70 years versus patients younger than 50 years.

Methods
We conducted a multicenter, prospective, comparative study of 40 patients younger than 50 years (group A) and 40 patients older than 70 years (group B) treated with arthroscopic rotator cuff repair. Patients older than 70 years were operated on only if symptoms persisted after 6 months of conservative treatment, whereas patients younger than 50 years were operated on regardless of any persistent symptoms. Imaging consisted of preoperative magnetic resonance imaging and postoperative ultrasound. Preoperative and postoperative function was evaluated with Constant and modified Constant scores. Patient satisfaction was also assessed. The evaluations were performed at least 1 year postoperatively.

Results
No patient was lost to follow-up. The incidence of both supraspinatus and infraspinatus tears was greater in group B. Greater retraction in the frontal plane and greater fatty infiltration were observed in group B. The Constant score was significantly improved in both groups (51 ± 12.32 preoperatively v 77.18 ± 11.02 postoperatively in group A and 48.8 ± 10.97 preoperatively v 74.6 ± 12.02 postoperatively in group B, P < .05). The improvement was similar in both groups. The modified Constant score was also significantly improved in both groups (57.48 ± 18.23 preoperatively v 81.35 ± 19.75 postoperatively in group A and 63.09 ± 14.96 preoperatively v 95.62 ± 17.61 postoperatively in group B, P < .05). The improvement was greater for group B (P < .05). Partial rerupture of the rotator cuff occurred in 2 cases in group A and 5 cases in group B. Complete rerupture was observed in 2 patients in group B. In group A, 29 patients (72.5%) were very satisfied, 8 (20%) were satisfied, and 3 (7.5%) were less satisfied. In group B, 33 patients (82.5%) were very satisfied, 6 (15%) were satisfied, and only 1 (2.5%) was less satisfied.

Conclusions
Rotator cuff tears are characterized by greater retraction in the frontal plane and greater fatty infiltration in patients older than 70 years compared with patients younger than 50 years. After arthroscopic repair, healing is greater for patients younger than 50 years. Functional gain is at least equal between the 2 groups.
Level of Evidence: Level IV, therapeutic case series.

Rodilla/Knee: en la gonartrosis mejor pinchar, peor el paracetamol

Pharmacologic Interventions for Knee OA

Raveendhara R, Christopher H,  David M, Elizaveta E,  John B,  Timothy E,

Ann Intern Med. 6 January 2015,162(1):46-54

Background: The relative efficacy of available treatments of knee osteoarthritis (OA) must be determined for rational treatment algorithms to be formulated.

Purpose: To examine the efficacy of treatments of primary knee OA using a network meta-analysis design, which estimates relative effects of all treatments against each other.

Data Sources: MEDLINE, EMBASE, Web of Science, Google Scholar, Cochrane Central Register of Controlled Trials from inception through 15 August 2014, and unpublished data.

Study Selection: Randomized trials of adults with knee OA comparing 2 or more of the following: acetaminophen, diclofenac, ibuprofen, naproxen, celecoxib, intra-articular (IA) corticosteroids, IA hyaluronic acid, oral placebo, and IA placebo.

Data Extraction: Two reviewers independently abstracted study data and assessed study quality. Standardized mean differences were calculated for pain, function, and stiffness at 3-month follow-up.

Data Synthesis: Network meta-analysis was performed using a Bayesian random-effects model; 137 studies comprising 33 243 participants were identified. For pain, all interventions significantly outperformed oral placebo, with effect sizes from 0.63 (95% credible interval [CrI], 0.39 to 0.88) for the most efficacious treatment (hyaluronic acid) to 0.18 (CrI, 0.04 to 0.33) for the least efficacious treatment (acetaminophen). For function, all interventions except IA corticosteroids were significantly superior to oral placebo. For stiffness, most of the treatments did not significantly differ from one another.

Limitation: Lack of long-term data, inadequate reporting of safety data, possible publication bias, and few head-to-head comparisons.

Conclusion: This method allowed comparison of common treatments of knee OA according to their relative efficacy. Intra-articular treatments were superior to nonsteroidal anti-inflammatory drugs, possibly because of the integrated IA placebo effect. Small but robust differences were observed between active treatments. All treatments except acetaminophen showed clinically significant improvement from baseline pain. This information, along with the safety profiles and relative costs of included treatments, will be helpful for individualized patient care decisions.

Raquis/Spine: Tras la compresion vertebral el resultado no depende de la ortesis

Comparative Study of the Treatment Outcomes of Osteoporotic Compression Fractures without Neurologic Injury Using a Rigid Brace, a Soft Brace, and No Brace

A Prospective Randomized Controlled Non-Inferiority Trial

Ho-Joong Kim, MD; Je-Min Yi, MD; Hyeon-Guk Cho, MD; Bong-Soon Chang, MD; Choon-Ki Lee, MD; Jee Hyoung Kim, MD; Jin S. Yeom, MD

J Bone Joint Surg Am, 2014 Dec 03; 96 (23): 1959 -1966

Abstract

Background:
The efficacy of brace application for the treatment of osteoporotic compression fractures remains unclear. The purpose of this study was to compare the treatment outcomes in patients with osteoporotic compression fractures with regard to whether the patients had no braces, rigid braces, or soft braces.

Methods:
We randomly assigned sixty patients with acute one-level osteoporotic compression fractures within three days of injury to the no-brace, soft-brace, and rigid-brace groups through 1:1:1 allocation. The primary outcome was the baseline adjusted Oswestry Disability Index score at twelve weeks after compression fracture. The non-inferior margin of the Oswestry Disability Index was set at an average of 10 points.

Results:
The baseline adjusted Oswestry Disability Index score at twelve weeks after compression fracture in the no-brace group was not inferior to that in the soft-brace or rigid-brace groups. The mean adjusted Oswestry Disability Index score was 35.95 points (95% confidence interval, 25.42 to 46.47 points) in the no-brace group and 37.83 points (95% confidence interval, 26.77 to 48.90 points) in the soft-brace group, with a difference of −1.88 points (95% confidence interval, −7.02 to 9.38 points) between the groups. Similarly, the mean adjusted Oswestry Disability Index score was 35.95 points (95% confidence interval, 25.42 to 46.47 points) in the no-brace group and 33.54 points (95% confidence interval, 23.79 to 43.29 points) in the rigid-brace group, with a difference of 2.41 points (95% confidence interval, −7.86 to 9.27 points) between the groups. During the follow-up assessment period, there was no significant difference among the groups for the overall Oswestry Disability Index scores (p = 0.260), visual analog scale for pain scores for back pain (p = 0.292), and anterior body compression ratios (p = 0.237). However, the Oswestry Disability Index scores and the visual analog scale scores for back pain significantly improved with time after the fractures (p < 0.001), and the body compression ratios significantly decreased with time in all three groups (p < 0.001).

Conclusions:
The Oswestry Disability Index scores for the treatment of compression fractures without a brace were not inferior to those with soft or rigid braces. Moreover, the improvement in back pain and progression of anterior body compression were similar among the three groups.

Level of Evidence: Therapeutic Level I

Rodilla/Knee: Las tendencias en las PTR

Trends in Total Knee Arthroplasty Implant Utilization.
Nguyen LC, Lehil MS, Bozic KJ
J Arthroplasty. 2014 Dec 13. pii: S0883-5403(14)00940-1. doi: 10.1016/j.arth.2014.12.009. [Epub ahead of print]

Abstract

The incidence of total knee arthroplasty (TKA) has increased alongside our knowledge of knee physiology, kinematics, and technology resulting in an evolution of TKA implants. This study examines the trends in TKA implant utilization. Data was extracted from The Orthopedic Research Network to evaluate trends in level of constraint, fixed vs. mobile bearing, fixation, and type of polyethylene in primary TKAs. In 2012, 88% used cemented femoral and tibial implants, and 96% involved patellar resurfacing. 38% of implants were cruciate retaining, 53% posterior stabilized or condylar stabilized, 3% constrained. 91% were fixed-bearing, 7% mobile-bearing. 52% of tibial inserts were HXLPE. TKA implant trends demonstrate a preference for cemented femoral and tibial components, patellar resurfacing, fixed-bearing constructs, metal-backed tibial components, patellar resurfacing, and increased usage of HXLPE liners.

KEYWORDS:

Hombro/Shoulder: Los desgarros silentes del manguito crecen y dolerán

A prospective evaluation of survivorship of asymptomatic degenerative rotator cuff tears

Keener JD1, Galatz LM1, Teefey SA2, Middleton WD2, Steger-May K3, Stobbs-Cucchi G1, Patton R1, Yamaguchi K1.

J Bone Joint Surg Am. 2015 Jan 21;97(2):89-98. doi: 10.2106/JBJS.N.00099.

Abstract

BACKGROUND:
The purpose of this prospective study was to report the long-term risks of rotator cuff tear enlargement and symptom progression associated with degenerative asymptomatic tears.

METHODS:
Subjects with an asymptomatic rotator cuff tear in one shoulder and pain due to rotator cuff disease in the contralateral shoulder enrolled as part of a prospective longitudinal study. Two hundred and twenty-four subjects (118 initial full-thickness tears, fifty-six initial partial-thickness tears, and fifty controls) were followed for a median of 5.1 years. Validated functional shoulder scores were calculated (visual analog pain scale, American Shoulder and Elbow Surgeons [ASES], and simple shoulder test [SST] scores). Subjects were followed annually with shoulder ultrasonography and clinical evaluations.

RESULTS:
Tear enlargement was seen in 49% of the shoulders, and the median time to enlargement was 2.8 years. The occurrence of tear-enlargement events was influenced by the severity of the final tear type, with enlargement of 61% of the full-thickness tears, 44% of the partial-thickness tears, and 14% of the controls (p < 0.05). Subject age and sex were not related to tear enlargement. One hundred subjects (46%) developed new pain. The final tear type was associated with a greater risk of pain development, with the new pain developing in 28% of the controls, 46% of the shoulders with a partial-thickness tear, and 50% of those with a full-thickness tear (p < 0.05). The presence of tear enlargement was associated with the onset of new pain (p < 0.05). Progressive degenerative changes of the supraspinatus muscle were associated with tear enlargement, with supraspinatus muscle degeneration increasing in 4% of the shoulders with a stable tear compared with 30% of the shoulders with tear enlargement (p < 0.05). Nine percent of the shoulders with a stable tear showed increased infraspinatus muscle degeneration compared with 28% of those in which the tear had enlarged (p = 0.07).

CONCLUSIONS:
This study demonstrates the progressive nature of degenerative rotator cuff disease. The risk of tear enlargement and progression of muscle degeneration is greater for shoulders with a full-thickness tear, and tear enlargement is associated with a greater risk of pain development across all tear types.

LEVEL OF EVIDENCE:
Prognostic Level II

Hombro/Shoulder: el tendón del supraespinoso más grueso en caso de impingement subacromial

Supraspinatus tendon and subacromial space parameters measured on ultrasonographic imaging in subacromial impingement syndrome

Michener LA1, Subasi Yesilyaprak SS, Seitz AL, Timmons MK, Walsworth MK.

Knee Surg Sports Traumatol Arthrosc. 2015 Feb;23(2):363-9. doi: 10.1007/s00167-013-2542-8. Epub 2013 Jun 5.

Abstract

PURPOSE:
To characterize the supraspinatus tendon thickness, subacromial space, and the relationship between tendon thickness and subacromial space to further elucidate the mechanisms of subacromial impingement syndrome.

METHODS:
In a single-blind cross-sectional study, subjects were recruited with subacromial impingement syndrome (n = 20) and asymptomatic controls (n = 20) matched for age, gender, and hand dominance. Ultrasound images were collected using a 4-12-MHz linear transducer in B-mode of the supraspinatus tendon in the transverse (short axis) and the anterior aspect of the subacromial space outlet. Using image callipers, measurements of tendon thickness were taken at 3 points along the tendon and averaged for a single thickness measure. The subacromial space outlet was measured via the acromiohumeral distance (AHD) defined by the inferior acromion and superior humeral head. The occupation ratio was calculated as the tendon thickness as a percentage of AHD.

RESULTS:
The subacromial impingement syndrome group had a significantly thicker tendon (mean difference = 0.6 mm, p = 0.048) and a greater tendon occupation ratio (mean difference = 7.5 %, p = 0.014) compared to matched controls. There were no AHD group differences.

CONCLUSIONS:
The supraspinatus tendon was thicker and occupied a greater percentage of AHD, supporting an intrinsic mechanism. An extrinsic mechanism of tendon compression is theoretically supported, but future imaging studies need to confirm direct compression with elevation. Treatment to reduce tendon thickness may reduce symptoms, and surgical intervention to increase subacromial space may be considered if tendon compression can be verified.

Rodilla/Knee: Menos muertes tras ptr pero se puede mejorar

45-day mortality after 467,779 knee replacements for osteoarthritis from the National Joint Registry for England and Wales: an observational study.

Hunt LP, Ben-Shlomo Y, Clark EM, Dieppe P, Judge A, MacGregor AJ, Tobias JH, Vernon K, Blom

Lancet. 2014 Oct 18;384(9952):1429-36.

Abstract

BACKGROUND:
Understanding the risk factors for early death after knee replacement could help to reduce the risk of mortality after this procedure. We assessed secular trends in death within 45 days of knee replacement for osteoarthritis in England and Wales, with the aim of investigating whether any change that we recorded could be explained by alterations in modifiable perioperative factors.

METHODS:
We took data for knee replacements done for osteoarthritis in England and Wales between April 1, 2003, and Dec 31, 2011, from the National Joint Registry for England and Wales. Patient identifiers were used to link these data to the national mortality database and the Hospital Episode Statistics database to obtain details of death, sociodemographics, and comorbidity. We assessed mortality within 45 days by Kaplan-Meier analysis and assessed the role of patient and treatment factors by Cox proportional hazards models.

FINDINGS:
 467,779 primary knee replacements were done to treat osteoarthritis during 9 years. 1183 patients died within 45 days of surgery, with a substantial secular decrease in mortality from 0·37% in 2003 to 0·20% in 2011, even after adjustment for age, sex, and comorbidity. The use of unicompartmental knee replacement was associated with substantially lower mortality than was total knee replacement (hazard ratio [HR] 0·32, 95% CI 0·19–0·54, p<0·0005). Several comorbidities were associated with increased mortality: myocardial infarction (HR 3·46, 95% CI 2·81–4·14, p<0·0005), cerebrovascular disease (3·35, 2·7–4·14, p<0·0005), moderate/severe liver disease (7·2, 3·93–13·21, p<0·0005), and renal disease (2·18, 1·76–2·69, p<0·0005). Modifiable perioperative risk factors, including surgical approach and thromboprophylaxis were not associated with mortality.

INTERPRETATION:
Postoperative mortality after knee replacement has fallen substantially between 2003 and 2011. Efforts to further reduce mortality should concentrate more on older patients, those who are male and those with specific comorbidities, such as myocardial infarction, cerebrovascular disease, liver disease, and renal disease.

FUNDING: National Joint Registry for England and Wales.

Rodilla/Knee: aprovechar que la vascularización de la rótula va en parte por medial

Quantitative assessment of patellar vascularity following bone-patellar tendon-bone autograft harvest for ACL reconstruction.

Jones KJ, Lazaro LE, Taylor SA, Pardee NC, Dyke JP, Hannafin JA, Warren RF, Lorich DG

Knee Surg Sports Traumatol Arthrosc. 2015 Jan 22. [Epub ahead of print]

Abstract

PURPOSE: 

Recent anatomic studies have suggested that the dominant arterial supply of the patella enters through the inferior pole. Based upon these findings, we hypothesized that bone-patellar tendon-bone graft harvest can significantly diminish patellar vascularity.

METHODS: 

Nine matched pair cadaveric knee specimens (mean age 47.4 years) were dissected and cannulated. A single knee was selected to undergo routine graft harvest, and the contralateral knee was left intact to serve as a control. Gadolinium was injected, and magnetic resonance imaging (MRI) signal enhancement was quantified to determine differences in uptake. Each matched pair was subsequently injected with a urethane polymer compound and dissected to correlate vessel disruption with MRI findings.

RESULTS: 

We identified two predominating patterns of vessel entry. In one pattern, the vessel entered the inferomedial aspect (five o'clock/right, seven o'clock/left) of the patella and was disrupted by graft harvest in 2/9 (22.2 %) pairs. In the second pattern, the vessel entered further medial (four o'clock/right, eight o'clock/left) and was not disrupted (7/9, 78.8 %). The mean decrease in gadolinium uptake following disruption of the predominant vessel measured 56.2 % (range 42.6-69.5 %) compared to an average decrease of 18.3 % (range 7.1-29.1 %) when the dominant arterial supply to the inferior pole remained intact (p < 0.04).

CONCLUSION: 

Medial entry of the predominant vessel precluded vessel disruption. Disruption of the dominant arterial supply can result in a significant decrease in patellar vascularity. Modification of graft harvest techniques and areas of surgical dissection should be explored to minimize vascular insult. Further correlation with clinical studies/outcomes is necessary to determine a potential association between vascular insult and anterior knee pain.