Primary Anterolateral Ligament Rupture in Patients Requiring Revision Anterior Cruciate Ligament Reconstruction: A Retrospective Case-Control Magnetic Resonance Imaging Review.

PURPOSE: To compare the initial rate of anterolateral ligament (ALL) injury at the time of anterior cruciate ligament (ACL) rupture in patients who subsequently experienced ACL reconstruction graft failure versus patients who did not experience subsequent ACL reconstruction graft failure. METHODS: Our institution's electronic medical record database was queried for patients who underwent primary ACL reconstruction with subsequent ACL graft rupture. Exclusion criteria included unavailable MRI scan, chronic ACL injury, multi-ligamentous injury, previous ACL reconstruction, and age younger than 13 or older than 50 years. Each patient was paired with an age-, gender-, and graft-matched control who underwent ACL reconstruction without subsequent graft rupture. Each patient was diagnosed with an intact, partially injured, or fully ruptured ALL on initial MRI. The location of ALL injury was also noted. The incidence and location of ALL rupture were compared using χ2 analysis. RESULTS: 1,967 patients underwent primary ACL reconstruction. 128 patients experienced ACL graft rupture, and 55 patients (43%) had MRI scans available for review. 39 of these patients fulfilled inclusion criteria and were matched with a control patient. In the revision group, the ALL was diagnosed as intact, partially torn, and completely torn in 17, 14, and 8 patients, respectively, compared to 18, 13, and 8 patients, respectively in the control group. No difference was found in frequency of ALL rupture (Pearson χ2 = 0.066; P = .968) or rupture location (Pearson χ2 = 4.00, P = 0.135). CONCLUSIONS: The incidence of initial ALL injury as documented on MRI was not different in patients who experienced subsequent ACL graft rupture compared with patients who did not experience ACL graft rupture after primary ACL reconstruction. The ALL was more commonly injured on the tibial side in patients with ACL graft rupture and femoral-sided lesions were more common in control patients. LEVEL OF EVIDENCE: Level III, prognostic case-control study.

Postoperative Shoulder Imaging: Rotator Cuff, Labrum, and Biceps Tendon.

Imaging interpretation of the postoperative shoulder is a challenging and difficult task for both the radiologist and the orthopedic surgeon. The increasing number of shoulder rotator cuff, labrum, and biceps tendon repairs performed in the United States also makes this task a frequent occurrence. Whether treatment is surgical or conservative, imaging plays a crucial role in patient care. Many imaging findings can be used to predict prognosis and functional outcomes, ultimately affecting treatment. In addition, evolving surgical techniques alter the normal anatomy and imaging appearance of the shoulder such that accepted findings proved to be pathologic in the preoperative setting cannot be as readily described as pathologic after surgery. An understanding of common surgical procedures of the shoulder can aid in recognizing normal expected postoperative findings and discerning common complications. Although magnetic resonance (MR) imaging and MR arthrography are widely used, implementing a multimodality imaging approach for evaluation of the postoperative shoulder can provide additional imaging information that may be decisive and vital to diagnosis. The high spatial resolution of both computed tomography with arthrography and ultrasonography makes them additional modalities to consider, especially when dealing with metal artifact. To provide an accurate radiologic interpretation of high clinical value, radiologists should approach the postoperative shoulder comprehensively with knowledge of the anatomy, surgical techniques and complications, clinical outcomes, and imaging pitfalls. ©RSNA, 2016.

Tip-of-the-Iceberg Fractures: Small Fractures That Mean Big Trouble.

OBJECTIVE: Several small and seemingly unimportant fractures are associated with other more serious injuries, usually to adjacent soft tissues. The purpose of this article is to discuss 11 of these injuries, in each case describing the fracture (the tip) and the injuries that lie beneath the surface (the iceberg). CONCLUSION: Some fractures should be considered analogous to the tip of an iceberg. Their recognition is important because the commonly associated injuries, which are often more serious than the fracture itself, are typically not evident on radiographs and require advanced imaging for accurate diagnosis and treatment.

An alternative injection technique for performing MR ankle arthrography: the lateral mortise approach.

OBJECTIVES: This study evaluates whether the recently described lateral mortise (LM) approach to therapeutic ankle injections can also be used to inject the ankle prior to magnetic resonance arthrography (MRA) without impairing the evaluation of the anterior talofibular ligament (ATFL). MATERIALS AND METHODS: An IRB-approved, retrospective review of ankle MRAs performed using the LM approach between April 2009 and April 2011 was conducted. The MRAs were independently evaluated by three musculoskeletal radiologists for: ATFL assessment (well assessed, limited or unable to assess), amount of fluid in the anterolateral soft tissues (none to large), and capsular distention (underdistended to overdistended). Patient age, gender, fluoroscopy time, injection location, degree of ankle arthritis, and ankle joint narrowing on radiographs were recorded. Statistical analysis was performed using exact binomial confidence limits. RESULTS: Fifteen MRAs were successfully performed on 13 patients (mean age: 27 years, 11 male, 2 female). Mean fluoroscopic time was 39 s (range 9­108) and mean volume injected was 7 mL (range 5­9 mL). The ATFL was well assessed on all MRAs. A moderate to large amount of fluid was noted in the anterolateral soft tissues on 5 out of 15 MRAs. No ankle joints were underdistended, but 3 out of 15 were overdistended. CONCLUSION: Since the ATFL is inferior to the location used for the LM injection, the interpretation of the ankle MRA, specifically ATFL evaluation, was not compromised in any patient. Therefore, the LM approach can be used as an alternative to the anteromedial approach for ankle MRA without sacrificing diagnostic quality.

Recognizing detachment-mode seafloor spreading in the deep geological past.

Large-offset oceanic detachment faults are a characteristic of slow- and ultraslow-spreading ridges, leading to the formation of oceanic core complexes (OCCs) that expose upper mantle and lower crustal rocks on the seafloor. The lithospheric extension accommodated by these structures is now recognized as a fundamentally distinct "detachment-mode" of seafloor spreading compared to classical magmatic accretion. Here we demonstrate a paleomagnetic methodology that allows unequivocal recognition of detachment-mode seafloor spreading in ancient ophiolites and apply this to a potential Jurassic detachment fault system in the Mirdita ophiolite (Albania). We show that footwall and hanging wall blocks either side of an inferred detachment have significantly different magnetizations that can only be explained by relative rotation during seafloor spreading. The style of rotation is shown to be identical to rolling hinge footwall rotation documented recently in OCCs in the Atlantic, confirming that detachment-mode spreading operated at least as far back as the Jurassic.

MRI of the elbow: techniques and spectrum of disease: AAOS exhibit selection.

BACKGROUND: Magnetic resonance imaging (MRI) of the elbow allows for high-resolution evaluation of osseous and soft-tissue structures, including ligaments, tendons, nerves, and muscles. Multiple imaging techniques and pulse sequences exist. The purpose of this article is to update orthopaedic surgeons on current MRI techniques and illustrate the spectrum of elbow pathology detectable by MRI. METHODS: We searched MEDLINE with use of the keywords "MRI" and "elbow" for studies less than five years old evaluating MRI techniques. These papers, our experience, and textbooks reviewing elbow MRI provided the information for this article. RESULTS: We discuss the essentials and applications of the following techniques: (1) conventional, non-gadolinium-enhanced MRI; (2) gadolinium-enhanced MRI; and (3) magnetic resonance arthrography. The classic MRI appearances of occult fractures, loose bodies, ulnar collateral ligament injuries, lateral collateral ligament complex injuries, biceps tendon injuries, triceps tendon injuries, lateral epicondylitis, medial epicondylitis, septic arthritis, osteomyelitis, osteochondritis dissecans, compression neuropathies, synovial disorders, and various soft-tissue masses are reviewed. CONCLUSIONS: MRI is a valuable, noninvasive method of elbow evaluation. This article updates orthopaedic surgeons on the various available MRI techniques and facilitates recognition of the MRI appearances of the most commonly seen pathologic elbow conditions.

Talofibular interval changes after acute ankle sprain: a stress ultrasonography study of ankle laxity.

INTRODUCTION: Quantifying talocrural joint laxity after ankle sprain is problematic. Stress ultrasonography (US) can image the lateral talocrural joint and allow the measurement of the talofibular interval, which may suggest injury to the anterior talofibular ligament (ATFL). The acute talofibular interval changes after lateral ankle sprain are unknown. METHODS: Twenty-five participants (9 male, 16 female; age 21.8 ± 3.2 y, height 167.8 ± 34.1 cm, mass 72.7 ± 13.8 kg) with 27 acute, lateral ankle injuries underwent bilateral stress US imaging at baseline (<7 d) and on the affected ankle at 3 wk and 6 wk from injury in 3 ankle conditions: neutral, anterior drawer, and inversion. Talofibular interval (mm) was measured using imaging software and self-reported function (activities of daily living [ADL] and sports) by the Foot and Ankle Ability Measure (FAAM). RESULTS: The talofibular interval increased with anterior-drawer stress in the involved ankle (22.65 ± 3.75 mm; P = .017) over the uninvolved ankle (19.45 ± 2.35 mm; limb × position F1,26 = 4.9, P = .035) at baseline. Inversion stress also resulted in greater interval changes (23.41 ± 2.81 mm) than in the uninvolved ankles (21.13 ± 2.08 mm). A main effect for time was observed for inversion (F2,52 = 4.3, P = .019, 21.93 ± 2.24 mm) but not for anterior drawer (F2,52 = 3.1, P = .055, 21.18 ± 2.34 mm). A significant reduction in the talofibular interval took place between baseline and week 3 inversion measurements only (F1,26 = 5.6, P = .026). FAAM-ADL and sports results increased significantly from baseline to wk 3 (21.9 ± 16.2, P < .0001 and 23.8 ± 16.9, P < .0001) and from wk 3 to wk 6 (2.5 ± 4.4, P = .009 and 10.5 ± 13.2, P = .001). CONCLUSIONS: Stress US methods identified increased talofibular interval changes suggestive of talocrural laxity and ATFL injury using anterior drawer and inversion stress that, despite significant improvements in self-reported function, only marginally improved during the 6 wk after ankle sprain. Stress US provides a safe, repeatable, and quantifiable method of measuring the talofibular interval and may augment manual stress examinations in acute ankle injuries.

Lateral mortise approach for therapeutic ankle injection: an alternative to the anteromedial approach.

OBJECTIVE: The purpose of this study was to evaluate the lateral mortise approach for performing therapeutic ankle injections. MATERIALS AND METHODS: Fluoroscopically guided ankle joint injections performed from November 2009 through June 2011 using the lateral ankle mortise approach were retrospectively reviewed. Data recorded included age, sex, fluoroscopic time, person performing the procedure, injection location, and preprocedure and postprocedure pain levels. Radiographs were reviewed for arthritis on a modified Kellgren-Lawrence scale, and the degree of anterior tibiotalar and lateral mortise narrowing was graded from none to severe. Univariate and multivariate statistical analyses were performed. RESULTS: Fifty-three injections were performed on 46 patients (mean age, 50.2 years; mean fluoroscopic time, 44.3 ± 47.3 seconds). Fifty injections in 44 patients were successful with the lateral mortise approach. The degrees of arthritis and anterior tibiotalar joint narrowing were moderate in 22.6% and 20.8% of cases and severe in 39.6% and 32.1% of cases. Lateral mortise narrowing was moderate in 9.4% and severe in 1.9% of cases. Average pre-procedure and postprocedure pain levels were 5.3/10 ± 2.4/10 and 1.7/10 ± 2.3/10. Multivariate analysis showed that increased fluoroscopic time was associated with moderate to severe lateral mortise narrowing (p = 0.011) but that arthritis score (p = 0.811) and degree of anterior tibiotalar joint narrowing (p = 0.416) were not. Pain reduction was associated with a higher preinjection pain score (p ≤ 0.001). CONCLUSION: The lateral mortise approach is an effective alternative to the anterior medial approach for performing therapeutic ankle injections. It is especially useful when moderate to severe ankle arthritis or anterior tibiotalar joint narrowing is present.

Imaging evaluation of the rotator cuff.

The rotator cuff is a complex network of interwoven tendons that plays a key role in glenohumeral movement and stability. Cuff abnormality is a common source of shoulder pain, but the clinical presentation is often nonspecific and, as a result, diagnostic imaging, especially magnetic resonance imaging, plays a key role in evaluating these patients. This article reviews imaging modalities available for evaluating the cuff, normal cuff anatomy, and common pathologic conditions that affect it.

Differences in lateral ankle laxity measured via stress ultrasonography in individuals with chronic ankle instability, ankle sprain copers, and healthy individuals.

STUDY DESIGN: Cross-sectional. OBJECTIVE: To use stress ultrasonography to measure the change in anterior talofibular ligament length during the simulated anterior drawer and ankle inversion stress tests. BACKGROUND: In approximately 30% of individuals, ankle sprains may eventually develop into chronic ankle instability (CAI) with recurrent symptoms. Individuals with CAI and those who have a history of ankle sprain (greater than 1 year prior) without chronic instability (copers) may or may not have mechanical laxity. METHODS: Sixty subjects (n=60 ankles) were divided into 3 groups: 1) Control subjects without ankle injury history (n=20; mean ± SD age; 24.8 ± 4.8 years; height, 173.7 ± 9.4 cm; weight, 77.2 ± 19.5 kg), ankle sprain copers (n=20; 22.3 ± 2.9 years; 172.8 ± 11.3 cm; 72.4 ± 14.3 kg), and subjects with CAI (n=20; 23.5 ± 4.2 years; 174.6 ± 9.6 cm; 74.8 ± 17.3 kg). Ligament length change with the anterior drawer and end range ankle inversion was calculated from ultrasound images. The Foot and Ankle Ability Measure (FAAM) was used to quantify self-reported function on activities-of-daily living (ADL) and sports. RESULTS: The anterior drawer test resulted in length changes that were greater (F2,57=6.2, P=.004) in the CAI (mean ± SD length change, 15.6 ± 15.1%, P=.006) and the coper groups (14.0 ± 15.9%, P=.016) compared to the control group (1.3 ± 10.7%); however the length change for the CAI and coper groups were not different (P=.93). Ankle inversion similarly resulted in greater ligament length change (F2,57=6.5, P=.003) in the CAI (25.3 ± 15.5%, P=.003) and coper groups (20.2 ± 19.6%, P=.039) compared to the control group (7.4 ± 12.9%); with no difference in length change between the copers and CAI groups (P=.59). The CAI group had a lower score on the FAAM-ADL (87.4 ± 13.4%) and FAAM-Sports (74.2 ± 17.8%) when compared to the control (98.8 ± 2.9% and 98.9 ± 3.1%, P<.0001) and coper groups (99.4 ± 1.8% and 94.6 ± 8.8%, P<.0001). CONCLUSION: Stress ultrasonography identified greater length changes of the anterior talofibular ligament in both the coper and CAI groups compared to the control group. Only subjects with CAI had reductions in self-reported function.

Contrast-enhanced magnetic resonance imaging positively impacts the management of some patients with rheumatoid arthritis or suspected RA.

OBJECTIVE: Early diagnosis of rheumatoid arthritis (RA) is important given the availability of highly effective disease-modifying antirheumatic (DMARD) medications, including biologics. However, because of associated risks and cost, accurately assessing disease activity is critical. Because magnetic resonance imaging (MRI) can detect synovitis and bone marrow edema, both of which may precede erosion development, we sought to determine the impact of enhanced MRI on patient management in a group of patients referred for MRI by rheumatologists. MATERIALS AND METHODS: After institutional review board approval, we evaluated all hand MRI examinations referred by the rheumatology department for synovitis evaluation between September 2007 and May 2009. The magnetic resonance images were classified as positive or negative and later reviewed by 2 musculoskeletal radiologists. A musculoskeletal radiologist and rheumatologist jointly reviewed the patients' medical records to determine the following: (1) Did the MRI findings alter treatment? (2) Were the treatment alterations beneficial? RESULTS: The study included 48 patients (39 women and 9 men) with a mean age of 51 years (range, 18-79 years). Significant management changes initially occurred in 79% (23/29) of the positive (DMARDs added in 20) and in 11% (2/19) of the negative MR examinations with average follow-up of ~300 days. Eighty percent (16/20) of the patients with DMARDs added experienced symptom improvement, none of the patients whose medications were discontinued experienced symptom relapse, and 18% (4/22) of patients without initial therapeutic changes required delayed treatment modifications. CONCLUSIONS: Enhanced MRI significantly altered clinical management in 50% of these patients with RA or suspected RA. Therefore, when the clinical picture in a patient with RA or suspected RA is unclear, enhanced MRI can provide useful guidance for treatment modifications.

Shoulder MR arthrography: intraarticular anesthetic reduces periprocedural pain and major motion artifacts but does not decrease imaging time.

PURPOSE: To prospectively determine whether the addition of an intraarticular anesthetic to the magnetic resonance (MR) arthrography solution has an effect on periprocedural pain, motion artifacts, and imaging time. MATERIALS AND METHODS: This study was approved by the institutional review board, and written informed consent was obtained from all patients. From September 2009 to March 2010, 127 patients, most imaged for shoulder pain, were randomized into two groups. The first group (group A, 63 patients) received intraarticular injection of gadopentetate dimeglumine, ropivacaine 0.5%, and normal saline in a ratio of 1:100:100. The second group (group B, 64 patients) received intraarticular injection of gadopentetate dimeglumine and normal saline in a ratio of 1:200. Pain was assessed before and after injection and immediately after 1.5-T MR imaging and rated on a scale of 0 to 10. Motion artifact was assessed by two musculoskeletal radiologists and two fellows by using a scale of 0 to 3 (0=no artifact, 1=artifact present but not affecting diagnostic image quality, 2=artifact present and diminishing diagnostic image quality, and 3=artifact present and rendering image nondiagnostic). MR imaging time and examinations with repeated sequences were recorded. Wilcoxon rank sum, analysis of covariance, and permutation data analyses were performed. RESULTS: The mean pain levels before injection, after injection, and after MR imaging were 3.5, 2.3, and 2.5, respectively, for group A and 3.6, 3.1, and 3.2 for group B. After adjusting for age, sex, and preinjection pain level, the mean differences in pre- and postinjection pain and preinjection pain and post-MR imaging pain between the two groups were -0.9 (P=.017) and -0.8 (P=.056), respectively. No significant difference in mean total MR imaging time or number of patients with repeat sequences was noted. Radiologists 1 and 2 recorded grade 2 or 3 motion in six and five patients, respectively, in group A and 15 and 14 patients, respectively, in group B (P=.047 and .048, respectively). Radiologists 3 and 4 recorded grade 2 or 3 motion in 13 and 23 patients, respectively, in group A and 23 and 33 patients, respectively, in group B (P=.093 and .110, respectively). CONCLUSION: The use of an intraarticular anesthetic significantly reduces periprocedural pain and major motion artifacts associated with MR shoulder arthrography; however, total MR imaging time is not reduced.

Overhead throwing injuries of the shoulder and elbow.

Injuries to the shoulder and elbow are common in athletes involved in sporting activities that require overhead motion of the arm. An understanding of the forces involved in the throwing motion, the anatomic structures most at risk, and the magnetic resonance imaging appearances of the most common associated injuries can help to improve diagnostic accuracy when interpreting imaging studies in these patients.

Assessment of scaphoid viability with MRI: a reassessment of findings on unenhanced MR images.

OBJECTIVE: The purpose of this article is to evaluate the accuracy of unenhanced T1-weighted MR images in predicting the vascular status of the proximal pole of the scaphoid in patients with chronic scaphoid fracture nonunions. MATERIALS AND METHODS: A database search identified 29 patients with chronic scaphoid nonunions who underwent a preoperative MRI examination and intraoperative assessment of scaphoid viability from 2004 to 2009. T1-weighted MR images were evaluated by two musculoskeletal radiologists. If the proximal pole demonstrated diffusely decreased T1-weighted signal (less than or equal to that of skeletal muscle), the patient was placed in a moderate-to-high risk for avascular necrosis (AVN) category. Otherwise, the patient was placed in a viable-to-low risk for AVN category. Scaphoid viability or necrosis was diagnosed intraoperatively depending on whether punctate bleeding was present. After the patients were classified according to the T1-weighted appearance, the appearance on STIR images was recorded. RESULTS: There were 29 patients (25 male) with a mean age of 21 years. When we compared the MRI results, using only the T1-weighted images, with the surgical findings, unenhanced MRI had a sensitivity, specificity, and accuracy of 55%, 94%, and 79%, respectively, for diagnosing AVN. Increased proximal pole STIR signal was noted with similar frequencies in patients with and without AVN. CONCLUSION: T1-weighted unenhanced MRI is an acceptable alternative to delayed contrast-enhanced MRI in the preoperative assessment of the vascular status of the proximal pole of the scaphoid in patients with chronic fracture nonunions. STIR images were not beneficial in determining proximal pole viability.

Massive rotator cuff tear in an adolescent athlete: a case report.

Full-thickness rotator cuff tears in the young athlete are a rare injury. These injuries typically result from an acute traumatic event in a contact athlete, as opposed to overuse injuries more commonly seen in throwing athletes. Acute tears may be initially overlooked, with the symptoms attributed to other, more common causes, such as cuff contusion or brachial plexus neuropraxia ("stinger" or "burner"). If undiagnosed, the tear may progress to an irreparable state at the time of eventual diagnosis. Therefore, rotator cuff tear must be included in the differential for acute shoulder injuries in the young athlete. This article presents a case of an adolescent athlete with a traumatic, massive rotator cuff tear that was diagnosed and managed promptly with excellent outcome.

Focal partial tears of the long head of the biceps brachii tendon at the entrance to the bicipital groove: MR imaging findings, surgical correlation, and clinical significance.

PURPOSE: The purpose of the study was to depict a subset of focal partial tears of the biceps brachii tendon, occurring at the entrance to the bicipital groove, which can be difficult to detect with MRI. SUBJECTS AND METHODS: The institutional review board approved this HIPAA-compliant study; informed consent was waived. The authors retrospectively reviewed imaging and medical records in 16 consecutive patients (12 men, 4 women; mean age, 57 years) who had prospective MRI diagnoses of tendinopathy and/or partial tearing of the intra-articular segment of the long head of the biceps brachii tendon (LHBT) at the entrance to the bicipital groove (restricted to within 1 cm of the groove entrance) and who also had surgical correlation within 4 months of imaging. RESULTS: Focal intrasubstance signal abnormality was noted in the tendons of 16 out of 16 (100%) patients. Focal tendon enlargement was noted in 8 out of 16 patients (50%). Fifteen out of 16 biceps partial tears (94%) were treated surgically. Shoulder pathology was restricted to the groove entrance in 4 out of 16 patients (25%). CONCLUSIONS: We depict a subset of focal partial tears of the biceps tendon, which can be difficult to detect on MRI because of their anatomical location at the entrance to the bicipital groove. Although they may coexist with other causes of shoulder pain, these lesions can also occur in isolation. In either case, they are potential causes of pain that can be addressed surgically.

Little Leaguer's shoulder (proximal humeral epiphysiolysis): MRI findings in four boys.

BACKGROUND: Shoulder pain is a common problem among adolescent athletes. A possible cause of such pain that can be diagnosed on MRI is a stress injury to the proximal humerus known as Little Leaguer's shoulder (proximal humeral epiphysiolysis). OBJECTIVE: Our objective was to describe the MRI appearance of Little Leaguer's shoulder. MATERIALS AND METHODS: Four patients (all boys; age range 11-15 years; median 13 years) with clinical, plain radiographic, and MR imaging findings of Little Leaguer's shoulder were studied retrospectively. RESULTS: MRI demonstrated focal physeal widening in all four boys with extension of physeal signal intensity into the metaphysis on T1-weighted and gradient echo coronal and sagittal sequences. T2-weighted sequences were of limited use in demonstrating the physeal widening, which is critical to the diagnosis. Abnormal high T2-signal intensity was seen in the metaphysis adjacent to the focal physeal widening in all the boys. CONCLUSION: Focal extension of normal physeal T1-weighted and gradient echo signal intensity into the adjacent metaphysis is a sign of stress injury in the proximal humeral physis (Little Leaguer's shoulder). Children should suspend the offending sport to allow healing.

Magnetic resonance imaging of the elbow: update on current techniques and indications.

The utility of magnetic resonance imaging of the elbow has noticeably improved over the past decade. Advances in equipment and refinement of pulse sequences has allowed for superior visualization of many pathologic processes involving the elbow joint and its surrounding structures. At this time, magnetic resonance imaging is most valuable in detecting occult fractures, osteochondritis dissecans, collateral ligament tears, nonossified intra-articular loose bodies, and soft tissue masses. It may also aid in the diagnosis of tendinous injuries, compression neuropathies, and synovial disorders. This article serves as an educational update for hand surgeons and illustrates the features of normal anatomy and specific disorders of the elbow.

Imaging of upper extremity stress fractures in the athlete.

Although it is much less common than injuries in the lower extremities, an upper extremity stress injury can have a significant impact on an athlete. If an accurate and timely diagnosis is to be made, the clinician must have a high index of suspicion of a stress fracture in any athlete who is involved in a throwing, weightlifting, or upper extremity weight-bearing sport and presents with chronic pain in the upper extremity. Imaging should play an integral role in the work-up of these patients; if initial radiographs are unrevealing, further cross-sectional imaging should be strongly considered. Although a three-phase bone scan is highly sensitive in this regard, MRI has become the study of choice at most centers.