Mortality rates at 10 years after metal-on-metal hip resurfacing compared with total hip replacement in England: retrospective cohort analysis of hospital episode statistics

Objectives To compare 10 year mortality rates among patients undergoing metal-on-metal hip resurfacing and total hip replacement in England.

Design Retrospective cohort study.

Setting English hospital episode statistics database linked to mortality records from the Office for National Statistics.

Population All adults who underwent primary elective hip replacement for osteoarthritis from April 1999 to March 2012. The exposure of interest was prosthesis type: cemented total hip replacement, uncemented total hip replacement, and metal-on-metal hip resurfacing. Confounding variables included age, sex, Charlson comorbidity index, rurality, area deprivation, surgical volume, and year of operation.

Main outcome measures All cause mortality. Propensity score matching was used to minimise confounding by indication. Kaplan-Meier plots estimated the probability of survival up to 10 years after surgery. Multilevel Cox regression modelling, stratified on matched sets, described the association between prosthesis type and time to death, accounting for variation across hospital trusts.

Results 7437 patients undergoing metal-on-metal hip resurfacing were matched to 22 311 undergoing cemented total hip replacement; 8101 patients undergoing metal-on-metal hip resurfacing were matched to 24 303 undergoing uncemented total hip replacement. 10 year rates of cumulative mortality were 271 (3.6%) for metal-on-metal hip resurfacing versus 1363 (6.1%) for cemented total hip replacement, and 239 (3.0%) for metal-on-metal hip resurfacing versus 999 (4.1%) for uncemented total hip replacement. Patients undergoing metal-on-metal hip resurfacing had an increased survival probability (hazard ratio 0.51 (95% confidence interval 0.45 to 0.59) for cemented hip replacement; 0.55 (0.47 to 0.65) for uncemented hip replacement). There was no evidence for an interaction with age or sex.

Conclusions Patients with hip osteoarthritis undergoing metal-on-metal hip resurfacing have reduced mortality in the long term compared with those undergoing cemented or uncemented total hip replacement. This difference persisted after extensive adjustment for confounding factors available in our data. The study results can be applied to matched populations, which exclude patients who are very old and have had complex total hip replacements. Although residual confounding is possible, the observed effect size is large. These findings require validation in external cohorts and randomised clinical trials.

 BMJ 2013;347:f6549

 http://www.bmj.com/content/347/bmj.f6549

Post-traumatic ulna plus variance associated with poor outcomes for distal radius fractures

Post-traumatic ulna plus variance associated with poor outcomes for distal radius fractures

Researchers in this study found that post-traumatic ulna plus variance greater than 2 mm was the only factor significantly associated with poor outcome when analyzing a cohort of young patients with unilateral distal radius fractures who were not yet at risk for osteoporosis.

“The present study showed that post-traumatic ulna [plus variance] is the most important factor in predicting bad outcome in non-osteoporotic patients, but that especially intra-articular fractures and to a lesser extent dorsal tilt may be of importance too,” the researchers wrote in the study abstract.

The researchers evaluated pre-reduction anteroposterior and lateral wrist radiographs from 66 patients with a median age of 42 years, according to the abstract. They measured fracture pattern, radial length, inclination, joint surface tilt, ulnar variance and measured outcomes using the Gartland and Werley score.

Although not statistically significant, the researchers noted that intra-articular fracture pattern may also be a strong marker for a poor outcome.

Beumer A. BMC Musculoskelet Disord. 2013. doi:10.1186/1471-2474-14-170.

Distal Radius Fractures: Is the use of locking plates justified?

Surgical Treatment of Distal Radial Fractures with a Volar Locking Plate Versus Conventional Percutaneous Methods: A Randomized Controlled Trial

Background:  The aim of this study was to compare the outcomes of displaced distal radial fractures treated with a volar locking plate with the results of such fractures treated with a conventional method of closed reduction and percutaneous wire fixation with supplemental bridging external fixation when required. Our aim was to ascertain whether the use of a volar locking plate improves functional outcomes.

Methods:  A single-center, pragmatic, randomized controlled trial was conducted in a tertiary care institution. One hundred and thirty patients (eighteen to seventy-three years of age) who had a displaced distal radial fracture were randomized to treatment with either a volar locking plate (n = 66) or a conventional percutaneous fixation method (n = 64). Outcome assessments were conducted at six weeks, twelve weeks, and one year. Outcomes were measured on the basis of scores on the Patient Evaluation Measure (PEM) and QuickDASH questionnaire (a shortened version of the Disabilities of the Arm, Shoulder and Hand, or DASH, Outcome Measure), EuroQol-5D (EQ-5D) scores, wrist range of motion, grip strength, and radiographic parameters.

Results:  The rate of follow-up at one year was 95%. Patients in the volar locking-plate group had significantly better PEM and QuickDASH scores and range of motion at six weeks compared with patients in the conventional-treatment group, but there were no significant differences between the two groups at twelve weeks or one year. Grip strength was better in the plate group at all time points. The volar locking plate was better at restoring palmar tilt and radial height. Significantly more patients in the plate group were driving at the end of six weeks, but this did not translate to a significant difference between groups in terms of those returning to work by that time.

Conclusions:  Use of a volar locking plate resulted in a faster early recovery of function compared with use of conventional methods. However, no functional advantage was demonstrated at or beyond twelve weeks. Use of the volar locking plate resulted in better anatomical reduction and grip strength, but there was no significant difference in function between the groups at twelve weeks or one year. The earlier recovery of function may be of advantage to some patients.


Karantana A et al. Surgical Treatment of Distal Radial Fractures with a Volar Locking Plate Versus Conventional Percutaneous Methods. J Bone Joint Surg Am 2013; 95: 1737–44; doi: 10.2106/JBJS.L.00232

More myths busted: Copper and magnet therapy are useless in rheumatoid arthritis

Folklore remedies for pain and inflammation in rheumatoid arthritis include the application of magnets and copper to the skin. Despite the popular use of devices containing magnets or copper for this purpose, little research has been conducted to evaluate the efficacy of such treatments.

Objective

To investigate whether the practice of wearing magnetic wrists straps, or copper bracelets, offers any specific therapeutic benefit for patients with rheumatoid arthritis.

Design

Randomised double-blind placebo-controlled crossover trial.

Methods

70 patients, aged 33 to 79 years and predominantly female (n = 52), with painful rheumatoid arthritis were recruited from general practices within Yorkshire. Participants were randomly allocated to wear four devices in a different order. Devices tested were: a standard (1502 to 2365 gauss) magnetic wrist strap, a demagnetised (<20 gauss) wrist strap, an attenuated (250 to 350 gauss) magnetic wrist strap, and a copper bracelet. Devices were each worn for five weeks, with treatment phases being separated by one week wash-out periods. The primary outcome measured was pain using a 100 mm visual analogue scale. Secondary pain measures were the McGill Pain Questionnaire and tender joint count. Inflammation was assessed using C-reactive protein and plasma viscosity blood tests and by swollen joint count. Physical function was assessed using the Health Assessment Questionnaire (Disability Index). Disease activity and medication use was also measured.

Results

65 participants provided complete self-report outcome data for all devices, four participants provided partial data. Analysis of treatment outcomes did not reveal any statistically significant differences (P>0.05) between the four devices in terms of their effects on pain, inflammation, physical function, disease activity, or medication use.

Principal findings

The results of this trial indicate that participants with rheumatoid arthritis obtained little if any specific therapeutic benefit from magnet therapy, involving the use of a 2200 gauss magnetic wrist strap for just over one month. The experimental wrist strap, which was typical of other commonly available devices as regards its magnetic properties and method of application, did not appear to outperform: (a) a very weak (300 gauss) magnetic wrist strap; (b) a non-magnetic wrist strap; or (c) a copper bracelet. Whilst estimated 95% confidence intervals for the individual comparison of experimental and control devices indicate that use of the standard magnetic wrist strap may have resulted in a modest reduction in pain, equivalent to 12 mm on a 100 mm pain VAS, they also indicate the possibility that use of this device may have resulted in a slight increase in pain. Despite such uncertainty, these differences may be viewed as small in terms of potential clinical relevance, and further results obtained for secondary pain measures failed to indicate any analgesic benefit whatsoever resulting from magnet therapy. No overall statistically significant differences were found between experimental and control devices for the primary pain outcome measure (i.e. pain VAS), the McGill Pain Questionnaire, self-assessed measures of tender and swollen joints, disease activity status, physical function, feelings of helplessness, or for two different blood tests used for monitoring levels of acute phase reactants as indicators of bodily inflammation, even when controlling for medication use, local rather than systemic inflammation, and non-compliance. Similarly, we did not observe any evidence, of statistical significance or likely clinical importance, to suggest superiority of the copper bracelet over other control devices.

Conclusions

Wearing a magnetic wrist strap or a copper bracelet did not appear to have any meaningful therapeutic effect, beyond that of a placebo, for alleviating symptoms and combating disease activity in rheumatoid arthritis.

 Richmond JS et al. Copper Bracelets and Magnetic Wrist Straps for Rheumatoid Arthritis – Analgesic and Anti-Inflammatory Effects: A Randomised Double-Blind Placebo Controlled Crossover Trial. PLoS ONE 20138(9): e71529

Decompression for cervical spondylotic myelopathy has potential to reverse neurological damage

At the 1-year follow-up, researchers who performed surgical decompression in patients with cervical spondylotic myelopathy found significantly improved disability-related, functional and quality-of-life outcomes, according to a study recently published in Journal of Bone & Joint Surgery.

“The results of this trial support the use of decompression surgery as a viable treatment for cervical spondylotic myelopathy and could lead to a change in practice to treat this condition,” neurosurgeon Michael G. Fehlings, who is medical director of the Krembil Neuroscience Centre at Toronto Western Hospital, stated in a press release. “With few existing interventions available for these patients, it is encouraging to have data showing improvements in quality of life as a result of surgery, in some cases, even reversing serious neurological damage that could have resulted in paralysis.”

 

Fehlings and colleagues analyzed results from a trial with 278 patients who had mild, moderate or severe cervical spondylotic myelopathy (CSM) conducted between 2005 and 2007 at 12 centers in the United States and Canada. Of the patients enrolled, 222 patients had 1-year follow-up data available.

The researchers found improved modified Japanese Orthopaedic Association, Neck Disability Index, SF-36 version 2 and Nurick grade scores in all patients between baseline and 1-year postoperative, according to the abstract. The rate of improvement did not depend upon preoperative CSM severity, and after a multivariate analysis, the results were unchanged when they adjusted for confounders.

“Although all patients experienced improvement in their condition after surgery, the challenge now is to ensure patients suffering from CSM receive surgical intervention in the earlier stages of the disease,” Fehlings said. “This approach ensures patients avoid permanent neurological impairment, and will reduce costs to the healthcare system over the long term.”

Reference:
Fehlings MG. J Bone Joint Surg Am. 2013;doi:10.2106/JBJS.L.00589.

5 Myth busters in Orthopaedivcs

Five Things Physicians and Patients Should Question

According to the AAOS, there are 5 myths that do not bring a substantial EBM based benefit for the orthopaedc patient. 

1

Avoid performing routine post-operative deep vein thrombosis ultrasonography screening in patients who undergo elective hip or knee arthroplasty.

Since ultrasound is not effective at diagnosing unsuspected deep vein thrombosis (DVT) and appropriate alternative screening tests do not exist, if there is no change in the patient’s clinical status, routine post-operative screening for DVT after hip or knee arthroplasty does not change outcomes or clinical management.

2

Don’t use needle lavage to treat patients with symptomatic osteoarthritis of the knee for long-term relief.

The use of needle lavage in patients with symptomatic osteoarthritis of the knee does not lead to measurable improvements in pain, function, 50-foot walking time, stiffness, tenderness or swelling.

3

Don’t use glucosamine and chondroitin to treat patients with symptomatic osteoarthritis of the knee.

Both glucosamine and chondroitin sulfate do not provide relief for patients with symptomatic osteoarthritis of the knee.

4

Don’t use lateral wedge insoles to treat patients with symptomatic medial compartment osteoarthritis of the knee.

In patients with symptomatic osteoarthritis of the knee, the use of lateral wedge or neutral insoles does not improve pain or functional outcomes. Comparisons between lateral and neutral heel wedges were investigated, as were comparisons between lateral wedged insoles and lateral wedged insoles with subtalar strapping. The systematic review concludes that there is only limited evidence for the effectiveness of lateral heel wedges and related orthoses. In addition, the possibility exists that those who do not use them may experience fewer symptoms from osteoarthritis of the knee.

5

Don’t use post-operative splinting of the wrist after carpal tunnel release for long-term relief.

Routine post-operative splinting of the wrist after the carpal tunnel release procedure showed no benefit in grip or lateral pinch strength or bowstringing. In addition, the research showed no effect in complication rates, subjective outcomes or patient satisfaction. Clinicians may wish to provide protection for the wrist in a working environment or for temporary protection. However, objective criteria for their appropriate use do not exist. Clinicians should be aware of the detrimental affects including adhesion formation, stiffness and prevention of nerve and tendon movement.

American Academy of Orthopedic Surgeons. Choosing Wisely®. Five Things Physicians and Patients Should Question. Online 11. September 2013

Incidence of displacement after nondisplaced distal radial fractures in adults.

BACKGROUND:

It is standard practice to closely monitor distal radial fractures treated nonoperatively to ensure that there is no fracture displacement. Patients are often asked to initially return weekly for radiographs. To our knowledge, nondisplaced distal radial fractures in adults have not been specifically evaluated to determine if this level of vigilance is required. If this subset of fractures is unlikely to displace, the cost, radiation exposure, and inconvenience of weekly office visits could be spared.

METHODS:

Using our billing database, we identified 642 closed distal radial fractures among the patients who presented to our institution during the four-year period from the beginning of 2006 to the end of 2009. Radiographs of the injuries were reviewed to identify fractures for which radiographic measurements were within predefined radiographic norms. Only those fractures that were believed to be nondisplaced by all reviewers were classified as nondisplaced for the purposes of this study. Radiographic measurements were made at the time of injury and at the time of fracture union to evaluate for displacement over time. The total number of clinic visits and radiographs that were received were calculated from the longitudinal medical record for each patient.

RESULTS:

Eighty-two fractures were identified as nondisplaced. None displaced or required operative intervention. The largest measured difference from injury to fracture union for radial inclination was 3.6° (average 0.8°); for radial height, 2.1 mm (average 0.5 mm); and for palmar tilt, 3.1° (average 1.0°). These numbers are all within the error of measurement.

CONCLUSIONS:

Nondisplaced distal radial fractures in adults appear to be inherently stable, and it may be appropriate to treat this subset of distal radial fractures with cast immobilization (when swelling allows) and a single follow-up visit with radiographs to document union at the time of cast removal.

LEVEL OF EVIDENCE:

Prognostic Level III.

Roth KM, Blazar PE, Earp BE, Han R, Leung A: Incidence of displacement after nondisplaced distal radial fractures in adults.J Bone Joint Surg Am. 2013 Aug 7;95(15):1398-402. doi: 10.2106/JBJS.L.00460.