Ambiguous Nomenclature in Musculoskeletal Magnetic Resonance Imaging.

INTRODUCTION: Medical vocabulary that conveys different meanings to different groups of readers can lead to confusion and potential misinterpretation of diagnoses. This article reviews words used by radiologists that convey information to the orthopedic surgeon and patient that is different from what the radiologist intended. These terms include meniscal tears, ligament sprains, partial tendon tears, bone bruises, bone contusions, articular cartilage injury, disc bulges, disc herniations, and joint subluxation. These words can, for example, suggest a traumatic etiology when in fact the condition is atraumatic, and they can imply a surgical treatment where none is indicated. This problem is further magnified in the arena of personal injury litigation. MATERIALS AND METHODS: The terms tear, bruise, contusion, injury, sprain, bulge, herniation, and subluxation are defined and analyzed for their ambiguous use, i.e., their actual versus intended meaning or other interpretation. RESULTS: Abnormalities and variations observed on musculoskeletal magnetic resonance (MR) images are often multi-factorial and may not be the source of any given patient's symptoms. The same MR image findings can have a congenital, traumatic, or degenerative source. CONCLUSIONS: Radiology vocabulary that invokes a singular traumatic event as a cause of an MRI finding can significantly mislead patients (as well as judges and juries). We propose that some terms be either avoided entirely when the findings are of uncertain etiology. At the very least, the various meanings of the terms need to be spelled out. Greater cooperation between orthopedic surgeons and radiologists on this matter would be beneficial to patient care.

Approach to the Patient with Disproportionate Pain.

Faced with a patient who presents with unexplained disproportionate pain, a surgeon may be tempted to diagnose a low pain threshold, malingering, poor coping, anxiety, or other emotional condition. However, a variety of conditions must be ruled out before the orthopedist can prescribe watchful waiting. Computed tomography and magnetic resonance imaging can detect occult fractures, acute spinal conditions or vascular occlusions, but early on are inadequate to diagnose a compartment syndrome, necrotizing fasciitis, or reflex sympathetic dystrophy (RSD). These diagnoses underpin a pain-out-of-proportion situation whereby the patient presents with disproportionate pain following a sometimes minor trauma with normal imaging studies and otherwise nonspecific presentations. Though these conditions are well described in the literature, investigations of malpractice data reveal a non-negligible prevalence of missed diagnoses for each of these entities. Determining that a patient exhibits otherwise unexplained pain-out-of-proportion situation is the first step in making a timely diagnosis.

Lawsuits After Primary and Revision Total Hip Arthroplasties: A Malpractice Claims Analysis.

BACKGROUND: As the prevalence of total hip arthroplasty (THA) expands, so too will complications and patient dissatisfaction. The goal of this study was to identify the common etiologies of malpractice suits and costs of claims after primary and revision THAs. METHODS: Analysis of 115 malpractice claims filed for alleged neglectful primary and revision THA surgeries by orthopedic surgeons insured by a large New York state malpractice carrier between 1983 and 2011. RESULTS: The incidence of malpractice claims filed for negligent THA procedures is only 0.15% per year in our population. In primary cases, nerve injury ("foot drop") was the most frequent allegation with 27 claims. Negligent surgery causing dislocation was alleged in 18 and leg length discrepancy in 14. Medical complications were also reported, including 3 thromboembolic events and 6 deaths. In revision cases, dislocation and infection were the most common source of suits. The average indemnity payment was $386,153 and the largest single settlement was $4.1 million for an arterial injury resulting in amputation after a primary hip replacement. The average litigation cost to the insurer was $61,833. CONCLUSION: Nerve injury, dislocation, and leg length discrepancy are the most common reason for malpractice after primary THA. Orthopedic surgeons should continue to focus on minimizing the occurrence of these complications while adequately incorporating details about the risks and limitations of surgery into their preoperative education.

The Contribution of Different Femur Segments to Overall Femoral Torsion.

BACKGROUND: Femoral torsion is a critical parameter in hip and knee disorders. The unproven assumption is that the femoral neck exclusively contributes to the overall torsion of the femur. PURPOSE/HYPOTHESIS: The aim of this study was to measure femoral torsion at different levels in patients with abnormally high or low femoral torsion and to compare the results with healthy volunteers. Our hypothesis was that the pattern of torsion distribution among the different femoral levels varies between patients with abnormal torsion and healthy volunteers. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Magnetic resonance images of patients with a history of patellar instability and torsion of the femur ≥25° (11 patients, 16 femurs) and ≤0° (14 patients, 22 femurs) were analyzed. Our controls were 30 healthy volunteers (60 femurs). To assess femoral torsion, 4 lines were drawn: a first line through the center of the femoral head and neck, a second line through the center of the femur at the top of the lesser trochanter, a third line tangent to the posterior aspect of the distal femur just above the attachment of the gastrocnemius, and a fourth line tangent to the posterior condyles. Three investigators performed the measurements; 1 performed the measurements twice. RESULTS: All femur segments showed significantly different torsion among the high-torsion, low-torsion, and control groups. Regarding the pattern of torsion distribution, on average, all levels contributed to the torsion. The ratio between the average neck and shaft torsion shifted toward a higher value in the high-torsion group, mostly because of a lack of external torsion in the shaft, and toward a lower value in the low-torsion group, owing to both a lack of internal torsion of the neck and increased external torsion in the shaft. CONCLUSION: We established a difference between neck, mid, and distal femoral torsion with reproducible measurements. Our data suggest that all 3 levels of the femur contribute to the total femoral torsion, with a different pattern among patients with high torsion and patellar instability.

Prevalence of modifiable surgical site infection risk factors in hip and knee joint arthroplasty patients at an urban academic hospital.

Surgical site infections after hip and knee arthroplasty can be devastating if they lead to periprosthetic joint infection. We examined the prevalence of the modifiable risk factors for surgical site infection described by the American Academy of Orthopaedic Surgery Patient Safety Committee. Our study of 300 cases revealed that only 20% of all cases and 7% of revision cases for infection had no modifiable risk factors. The most common risk factors were obesity (46%), anemia (29%), malnutrition (26%), and diabetes (20%). Cases with obesity or diabetes were associated with all histories of remote orthopedic infection, 89% of urinary tract infections, and 72% of anemia cases. The high prevalence of several modifiable risk factors demonstrates that there are multiple opportunities for perioperative optimization of such comorbidities.

Congruous versus incongruous patellar tilt--a preliminary study.

UNLABELLED: Although the presence of patellar tilt usually implies a tight lateral retinaculum and unhealthy pressure distributions within the patellar cartilage, it is possible for the bony portion of the patella to appear tilted while the articular cartilage is in fact fully congruous in a medial-lateral direction. We call this "congruous tilt." In such cases, a patient may not suffer from an excessive lateral pressure phenomenon, despite the presence of tilt. MATERIALS AND METHODS: One hundred and forty-nine knee MRIs were evaluated with respect to patellar tilt and Wiberg morphology. RESULTS: Thirty-one patellae were tilted (tilt angle > 10°). Twenty-five of 31 patellae demonstrated normal morphology in the axial plane (Wiberg 2). One of these 25 tilted patellae demonstrated congruous tilt. Three of 31 patellae were of the Wiberg type 3(a long lateral facet, a very short medial facet). In two out three of these, the tilt was deemed to be congruous. CONCLUSION: Based on this preliminary study, a tilted patella of the Wiberg 3 variety is likely to demonstrate congruous tilt. It remains to be determined whether patients with congruous tilt are less prone to pain but more prone to instability than their incongruous counterparts.

The intra- and inter-observer reliability of the physical examination methods used to assess patients with patellofemoral joint instability.

BACKGROUND: An accurate physical examination of patients with patellar instability is an important aspect of the diagnosis and treatment. While previous studies have assessed the diagnostic accuracy of such physical examination tests, little has been undertaken to assess the inter- and intra-tester reliability of such techniques. The purpose of this study was to determine the inter- and intra-tester reliability of the physical examination tests used for patients with patellar instability. METHODS: Five patients (10 knees) with bilateral recurrent patellar instability were assessed by five members of the International Patellofemoral Study Group. Each surgeon assessed each patient twice using 18 reported physical examination tests. The inter- and intra-observer reliability was assessed using weighted Kappa statistics with 95% confidence intervals. RESULTS: The findings of the study suggested that there were very poor inter-observer reliability for the majority of the physical tests, with only the assessments of patellofemoral crepitus, foot arch position and the J-sign presenting with fair to moderate agreement respectively. The intra-observer reliability indicated largely moderate to substantial agreement between the first and second tests performed by each assessor, with the greatest agreement seen for the assessment of tibial torsion, popliteal angle and the Bassett's sign. CONCLUSIONS: For the common physical examination tests used in the management of patients with patellar instability inter-observer reliability is poor, while intra-observer reliability is moderate. Standardization of physical exam assessments and further study of these results among different clinicians and more divergent patient groups is indicated.

The female knee: anatomic variations and the female-specific total knee design.

UNLABELLED: The concept and need for a gender-specific or female-specific total knee prosthesis have generated interest and discussion in the orthopaedic community and the general public. This concept relies on the assumption of a need for such a design and the opinion that there are major anatomic differences between male and female knees. Most of the information regarding this subject has been disseminated through print and Internet advertisements, and through direct-to-patient television and magazine promotions. These sources and a recent article in a peer-reviewed journal, which support the need for a female-specific implant design, have proposed three gender-based anatomic differences: (1) an increased Q angle, (2) less prominence of the anterior medial and anterior lateral femoral condyles, and (3) reduced medial-lateral to anterior-posterior femoral condylar aspect ratio. We examined the peer-reviewed literature to determine whether women have had worse results than men after traditional TKAs. We found women have equal or better results than men. In addition, we reviewed the evidence presented to support these three anatomic differences. We conclude the first two proposed differences do not exist, and the third is so small that it likely has no clinical effect. LEVEL OF EVIDENCE: Level IV, systematic review. See the Guidelines for Authors for a complete description of levels of evidence.

The pathophysiology of patellofemoral arthritis.

Faced with a patient suffering from patellofemoral arthritis, the surgeon must determine the pathophysiology of the condition, because different causes demand different treatments. Possible causes include malalignment, patellofemoral dysplasia, patellofemoral instability, patellofemoral trauma, obesity, osteoarthritis, inflammatory arthritis, and a genetic predisposition. Arthritis secondary to malalignment, dysplasia, instability, or trauma is less likely than arthritis secondary to the other causes to progress to femorotibial arthritis.

Patellar tilt: the physical examination correlates with MR imaging.

Patella malalignment is a recognized cause of knee pain, tilt being one of its more common forms. Although patellar tilt has been described both on the physical examination and on computerized imaging, to date the correlation between the two has not been established. A strong correlation would strengthen the value of each. Moreover, in situations where tilt cannot be clinically assessed (e.g. obesity), CT or MR imaging could be an adequate substitute for the clinical determination of tilt. We propose to correlate the physical examination with the magnetic resonance examination by way of an MR Tilt Angle. This angle is measured in a manner similar to the assessment of tilt on the physical examination, in that a line is drawn across the medial and lateral borders of the patella and referenced off the posterior femoral condyles. Most tilt angles use the slope of the lateral facet as a measure of tilt. These tilt angles paradoxically diminish as patellar tilt increases, a potential source of confusion. In this study, we use an MRI tilt angle that increases in the same direction as the actual tilt, which is more intuitive. We examined 30 patients with tilt and 51 patients without tilt. Patients with significant tilt on the physical examination can be expected to have an MRI Tilt Angle that is 10 degrees or greater whereas an angle of less than 10 degrees is associated with the absence of significant tilt on the physical examination. This MRI Tilt Angle fills the need for an easy, objective, intuitive measure of tilt and is an excellent adjunct to the physical examination.

Patellar nomenclature: the Tower of Babel revisited.

Because we communicate mainly through words, it is important that terms be understood in the same manner by all readers. Unfortunately, the study of the patellofemoral joint is complicated by the use of expressions that hold different meanings for different readers. Ideally, the community of musculoskeletal physicians should agree on a single definition of terms, but until then, authors and speakers should define their terms clearly. Some terms, such as chondromalacia and patellofemoral syndrome, should be abandoned altogether. I propose a glossary of confusing terms pertaining to the patellofemoral joint, the various interpretations of these terms, and possible resolutions of these conflicts. Words and terms included in this review include chondromalacia, patellofemoral syndrome, anterior knee pain, subluxation, malalignment, proximal realignment, Roux procedure, and "normal."