Wassink S, van den Oever M.  Arthrodesis of the first metatarsophalangeal joint using a single screw:  retrospective analysis of 109 feet.  J Foot Ankle Surg.  2009 Nov-Dec; 48(6): 653-61. (PubMed ID: 19857821)

WHY did the authors undertake this study?
There are a number of options for fixation when considering arthrodesis of the first metatarsophalangeal joint, without a clear consensus or gold standard within the orthopedic and podiatric communities.  The aim of this study was to evaluate clinical outcomes of first metatarsophalangeal joint arthrodesis utilizing the authors’ preferred technique:  planar cuts with single 3.5mm intramedullary lag screw fixation.

HOW did they attempt to answer this question?
The primary outcome measure of the study was a mailed questionnaire consisting of a modified version of the American Orthopedic Foot and Ankle Society Hallux Metatarsophalangeal-Interphalangeal (AOFAS-HMI) foot score.  Further descriptive statistics of the surgical outcomes were also obtained from chart review.      

Inclusion criteria of the population cohort were all patients over a 10-year observation period that underwent 1st MPJ arthrodesis with the specific surgical technique.  Patients with incomplete medical records, co-morbidities that could impact arthrodesis rates, and all other surgical techniques were excluded.

WHAT were the specific results?
One hundred and nine feet in 89 patients were included in the chart review analysis.  Seventy-nine patients (88.8%) returned the questionnaire and were included in the functional outcome measurements.

The average post-operative modified AOFAS-HMI score was 50 points with a standard deviation of 12 and ranging from 10-60.  One hundred and four of the 109 arthrodeses (95.4%) healed uneventfully within 8 weeks of the surgery according to the chart review.  Fifty-seven patients (72%) were completely satisfied with the results of the operation, although hardware removal was performed in 85 feet (78%).

HOW did the authors interpret these results?
From these results, the authors concluded  that their technique of single 3.5mm intramedullary lag screw fixation provided comparable rates of osseous union and patient satisfaction with other techniques.

Franklin GM, Rahman EA, Turner JA, Daniell WE, Fulton-Kehoe D.  Opioid use for chronic low back pain:  a prospective, population-based study among injured workers in Washington state, 2002-2005.  Clin J Pain.  2009 Nov-Dec; 25(9): 743-51.

WHY did the authors undertake this study?
The prescription of long-term opioids for acute and chronic musculoskeletal complaints has dramatically risen over the last 20 years.  As physicians, our threshold for prescribing any opioid, as well as the prescription of stronger opioids, has significantly decreased.  The authors of this study undertook to determine (1) physician patterns of opioid prescription following initial presentation of a patient with an acute musculoskeletal complaint, (2) predictive factors of long-term patient opioid use, (3) the association of opioid use with improvement in patient symptoms, and (4) the quality of physician medical record documentation.

HOW did they attempt to answer this question?
A prospective cohort of patients (n=1843) were identified through workers’ compensation claims of acute back injury in the Washington State Department of Labor and Industries State Fund over a 2-year observation period.   Patient telephone interviews were conducted immediately and 1-year after the claim submission.  Physician medical records and pharmacy data were reviewed for the remainder of the outcome measures.

WHAT were the specific results?
A significant amount of data was extracted from this study including, but not limited to:

1. Most people did not require opioids following their injury, but those that did (42%, 781/1843) required them immediately (89% [694/781] at or near their first visit). Additionally, most patients received opioids for a period of less than 3 months (59%, 410/694), and only 16% (111/694) received them for the entire observation period.


2. The strongest predictor of long-term patient opioid use was the quantity of opioids received during the first 3 months. Workers who received at least 40mg of a morphine equivalent dose (MED) where 6 times as likely to receive long-term opioids.


3. Long term users did not have significant improvement in pain or function with opioids. Only 26% of long-term users reported greater than 30% improvement in pain with the opioids, and only 16% reported greater than 30% improvement in function.


4. Medical records were generally inadequate with respect to appropriate pain management documentation. Pain level was recorded less than 30% of time, functional level was recorded less than 1% of time, and plan of opiate treatment was recorded less than 15% of the time.

HOW did the authors interpret these results
The authors did not draw firm conclusions from their data, but certainly pointed out that much more work needs to be done in both physician and patient education with respect to opioid prescription.

Let’s take a closer look at the topic of validity of outcome measurement. The aim of the Wassink and van den Oever study was to “evaluate the clinical outcome of a technique” for arthrodesis of the 1st metatarsophalangeal joint.  To do this they choose to use the AOFAS Hallux Metatarsophalangeal-Interphalangeal foot score, which is a validated outcome measure.  But what does “validated” mean?  This may seem a little silly, but a validated outcome measure is one that is actually measuring what it is intending to measure.   For example, let’s say I wanted to perform a study on how “happy” people are.  To do this the only data I collect is the gross income of my population cohort.  I then conclude that people who have a higher gross income are “happier”.  Is this accurate?  Most people would agree that a person’s income doesn’t tell you a whole lot of information about how “happy” someone is.  My outcome measure in this situation isn’t really measuring what I intend it to.  Statistics are never that easy of course, but a basic question that I always ask myself when I read an article is “Does the outcome measure actually provide the information that the author’s think that it does?”  Particularly, sensitivity and specificity analyses must be performed to determine if a given outcome measure is valid.