Ariel A. Williams

Correlation Between Changes in Tibial Tuberosity–Trochlear Groove Distance and Patellar Position During Active Knee Extension on Dynamic Kinematic Computed Tomographic Imaging

PURPOSE The purpose of this study was to evaluate changes in tibial tuberosity-trochlear groove (TTTG) distance with knee flexion in patients with patellar instability and correlate it with patellar position. METHODS Patients with symptomatic patellar instability underwent dynamic kinematic computed tomography (CT) during a cycle of knee extension from flexion. Knee flexion angles and corresponding TTTG distances, bisect offset, and patellar tilt were measured. Of the 51 knees, 37 had data available for interpolation between 5° and 30°. Results were interpolated to standardized intervals between 5° and 30° of knee flexion. Repeated-measures analysis (to identify differences between TTTG measurements at various knee flexion angles) and linear regression models (to assess for correlations between TTTG distance and bisect offset and between TTTG distance and patellar tilt) were used. RESULTS Fifty-one symptomatic knees in 38 patients were available for analysis. Bisect offset and patellar tilt correlated significantly (P < .001) with TTTG distance over all flexion angles. Interpolated results for comparison resulted in 37 knees in which the mean TTTG distance of 17.2 ± 5.8 mm at 5° decreased to 15.5 ± 5.7, 13.0 ± 5.5, and 11.5 ± 4.9 mm at 10°, 20°, and 30° of knee flexion, respectively. Mean TTTG at 5° was 1.5 times greater than that at 30° (P < .001). At 5°, 70.3% (26 of 37) of knees had a TTTG distance of more than 15 mm; at 30°, only 24.3% (9 of 37) exceeded this threshold. CONCLUSIONS Knee flexion angle during imaging is a critical factor when measuring TTTG distance to evaluate patellofemoral instability. We found that the mean TTTG distance varied by 5.7 mm between 5° and 30° of flexion in patients with symptomatic instability, although this relationship was not completely linear. Bisect offset and patellar tilt measurements mirrored this pattern, suggesting that TTTG distance influences patellar tracking in these patients. LEVEL OF EVIDENCE Level IV, prognostic case series.

The Relationship Between Tibial Tuberosity-Trochlear Groove Distance and Abnormal Patellar Tracking in Patients With Unilateral Patellar Instability.

PURPOSE To evaluate the role of tibial tuberosity-trochlear groove (TT-TG) distance in patellofemoral kinematics by retrospectively reviewing the dynamic computed tomography scans of patients with unilateral patellofemoral instability and comparing unstable and contralateral asymptomatic knees. METHODS We reviewed all dynamic computed tomography scans obtained at one tertiary care hospital from 2008 through 2013 and identified 25 patients with a history of recurrent unilateral patellofemoral instability. During the scans, subjects performed active knee extension against gravity. Both knees were imaged simultaneously. Lateral patellar tilt (LPT) and bisect offset (BO) were measured to assess tracking. TT-TG distance was measured to assess alignment. Measurements were made in full extension, maximum flexion, and approximately 10° increments in between. The significance level was set at P < .05. RESULTS LPT, BO, and TT-TG distance were highest in extension and decreased with flexion. Measurements were higher in symptomatic than in asymptomatic knees, with significant differences identified for LPT, BO, and TT-TG distance at 5° and 15° and for TT-TG distance at 25° and 35° (P < .05). TT-TG distance was associated with LPT and BO, with r(2) values in symptomatic knees of 0.55 for TT-TG distance and LPT and of 0.45 for TT-TG distance and BO. CONCLUSIONS In patients with unilateral patellar instability, LPT, BO, and TT-TG distance are higher on the unstable side. An association exists between TT-TG distance and the tracking parameters studied, suggesting that TT-TG distance relates to patellar tracking, and a laterally positioned tibial tuberosity may predispose to instability episodes. LEVEL OF EVIDENCE Level IV, diagnostic study.

Trapezium Trabecular Morphology in Carpometacarpal Arthritis

PURPOSE In thumb carpometacarpal osteoarthritis, current evidence suggests that degenerative, bony remodeling primarily occurs within the trapezium. Nevertheless, the pathomechanics involved and the most common sites of wear remain controversial. Quantifying structural bone morphology characteristics with high-resolution computed tomography CT (micro-CT) infer regions of load transmission. Using micro-CT, we investigated whether predominant trabecular patterns exist in arthritic versus normal trapeziums. METHODS We performed micro-CT analysis on 13 normal cadaveric trapeziums and 16 Eaton stage III to IV trapeziums. We computationally divided each specimen into 4 quadrants: volar-ulnar, volar-radial, dorsal-radial, and dorsal-ulnar. Measurements of trabecular bone morphologic parameters included bone volume ratio, connectivity, trabecular number, and trabecular thickness. Using analysis of variance with post hoc Bonferroni/Dunn correction, we compared osteoarthritic and normal specimen quadrant measurements. RESULTS No significant difference existed in bone volume fraction between the osteoarthritic and normal specimens. Osteoarthritic trapeziums, however, demonstrated significantly higher trabecular number and connectivity than nonosteoarthritic trapeziums. Comparing the volar-ulnar quadrant of osteoarthritis and normal specimens collectively, this quadrant in both consistently possessed significantly higher bone volume fraction, trabecular number, and connectivity than the dorsal-radial and volar-radial quadrants. CONCLUSIONS The significantly greater trabecular bone volume, thickness, and connectivity in the volar-ulnar quadrant compared with the dorsal-radial and dorsal-ulnar quadrants provides evidence that the greatest compressive loads at the first carpometacarpal joint occur at the volar-ulnar quadrant of the trapezium, representing a consistently affected region of wear in both normal and arthritic states. CLINICAL RELEVANCE These findings suggest that trapezial trabecular morphology undergoes pathologic alteration. This provides indirect evidence that changes in load transmission occur with thumb carpometacarpal joint arthritis development.

Correction of humoral derangements from mutant superoxide dismutase 1 spinal cord

We sought to define molecular and cellular participants that mediate motor neuron injury in amyotrophic lateral sclerosis using a coculture system.

Imaging characteristics of contralateral asymptomatic patellofemoral joints in patients with unilateral instability.

PURPOSE To test the hypothesis that in patients with unilateral patellofemoral instability ( PI patellofemoral instability ), the contralateral asymptomatic joints have abnormal morphology and imaging features of osteoarthritis ( OA osteoarthritis ) at four-dimensional ( 4D four-dimensional ) computed tomography (CT). MATERIALS AND METHODS The institutional review board approved this HIPAA-compliant retrospective study. Informed consent was waived. Radiology records were reviewed to identify 25 patients (male-female ratio, 0.56; median age, 20 years; range, 13-43 years) with unilateral PI patellofemoral instability undergoing 4D four-dimensional CT and 25 age- and sex-matched control patients undergoing multidetector CT. Trochlear groove depth ( TGD trochlear groove depth ), tibial tuberosity-trochlear groove ( TT-TG tibial tuberosity-trochlear groove ) distance, and patellar height ratio ( PHR patellar height ratio ) were determined to compare morphology, and bisect offset ( BO bisect offset ) measurements were obtained to compare lateral displacement of the patella between the two groups by using the Wilcoxon rank-sum test. All images were interpreted by trained observers. Tracking patterns of the patellae were determined by obtaining BO bisect offset measurements at various flexion angles with 4D four-dimensional CT. RESULTS In the contralateral asymptomatic joints, TGD trochlear groove depth (median, 3.0 mm; 95% confidence interval [ CI confidence interval ]: 2.5, 4.6; P < .0001), TT-TG tibial tuberosity-trochlear groove (median, 15 mm; 95% CI confidence interval : 12.7, 18; P = .008), PHR patellar height ratio (median, 1.17; 95% CI confidence interval : 1.09, 1.2; P = .002), and patellar lateral displacement ( BO bisect offset , 85%; 95% CI confidence interval : 76.2%, 98.2%; P < .0001) were different from measurements obtained in the control group: TGD trochlear groove depth median, 5.0 mm (95% CI confidence interval : 2.2, 7.6); TT-TG tibial tuberosity-trochlear groove median, 10.9 mm (95% CI confidence interval : 3.4, 20.7); PHR patellar height ratio median, 0.92 (95% CI confidence interval : 0.67, 1.36); and BO bisect offset median, 63% (95% CI confidence interval : 59%, 68.4%). OA osteoarthritis was detected in 40% of asymmetrical contralateral joints (10 of 25). By using 4D four-dimensional CT data, multiple regression analysis demonstrated that TGD trochlear groove depth (P = .026) and BO bisect offset measurements obtained at 30° of knee flexion (P = .047) had an association with the presence of OA osteoarthritis . CONCLUSION Abnormal morphology and imaging features of OA osteoarthritis are relatively common in contralateral asymptomatic joints of young patients with unilateral PI patellofemoral instability .

Chondral Injuries and Irreparable Meniscal Tears Among Adolescents With Anterior Cruciate Ligament or Meniscal Tears Are More Common in Patients With Public Insurance

Background: Access to health care services is a critical component of health care reform and may differ among patients with different types of insurance. Hypothesis/Purpose: The purpose was to compare adolescents with private and public insurance undergoing surgery for anterior cruciate ligament (ACL) and/or meniscal tears. We hypothesized that patients with public insurance would have a delayed presentation from the time of injury and therefore would have a higher incidence of chondral injuries and irreparable meniscal tears and lower preoperative International Knee Documentation Committee (IKDC) scores than patients with private insurance. Study Design: Cross-sectional study; Level of evidence, 3. Methods: This was a retrospective study of patients under 21 years of age undergoing ACL reconstruction and/or meniscal repair or debridement from January 2013 to March 2016 at a single pediatric sports medicine center. Patients were identified by a search of Current Procedural Terminology (CPT) codes. A chart review was performed for insurance type; preoperative diagnosis; date of injury, initial office visit, and surgery; preoperative IKDC score; intraoperative findings; and procedures. Results: The study group consisted of 119 patients (mean age, 15.0 ± 1.7 years). Forty-one percent of patients had private insurance, while 59% had public insurance. There were 27 patients with isolated meniscal tears, 59 with combined meniscal and ACL tears, and 33 with isolated ACL tears. The mean time from injury to presentation was 56 days (range, 0-457 days) in patients with private insurance and 136 days (range, 0-1120 days) in patients with public insurance (P = .02). Surgery occurred, on average, 35 days after the initial office visit in both groups. The mean preoperative IKDC score was 53 in both groups. Patients with meniscal tears with public insurance were more likely to require meniscal debridement than patients with private insurance (risk ratio [RR], 2.3; 95% CI, 1.7-3.1; P = .02). Patients with public insurance were more likely to have chondral injuries of grade 2 or higher (RR, 4.4; 95% CI, 3.9-5.0; P = .02). Conclusion: In adolescent patients with ACL or meniscal tears, patients with public insurance had a more delayed presentation than those with private insurance. They also tended to have more moderate-to-severe chondral injuries and meniscal tears, if present, that required debridement rather than repair. More rapid access to care might improve the prognosis of young patients with ACL and meniscal injuries with public insurance.

Characterizing Patterns In Patellar Maltracking On Dynamic Kinematic CT Imaging

Objectives: Patellar maltracking has been traditionally difficult to assess due to its dynamic component. Unlike the assessment of malalignment, which relies on static radiographic measurements, maltracking is a dynamic phenomenon described subjectively with the J sign. The advent of dynamic, kinematic computed tomographic imaging (DKCT) has allowed for the dynamic assessment of the patellofemoral joint. We used DKCT to visualize and quantify patterns of patellar maltracking and correlated these findings with the presence or absence of symptoms of patellar instability. Methods: 76 knees in 38 subjects were analyzed using DKCT. Measurements of bisect offset at 10° intervals of knee flexion were performed for each knee during active flexion/extension cycles. Patterns in bisect offset were assessed and graded in terms of 1, 2 or 3 quadrants of lateral patellar motion, based on 75-100, 100-125, and >125% bisect offset. The presence or absence of symptomatic patellar instability were recorded for each knee, and ratios of patients with symptoms were calculated for J sign tracking patterns of grades 1, 2 and 3. Differences in ratios between Grades 1, 2 and 3 were calculated using chi squared analysis. Results: 76 knees were available for analysis, of which 51 had symptomatic patellar instability. 9 knees demonstrated normal patterns of tracking. 58 knees demonstrated increased lateral translation in extension. 7 knees showed persistent lateralization of the patella throughout range of motion, and 2 knees showed increased translation in flexion. In the 58 knees that showed maximal lateral translation in extension (J sign), the J sign was graded as 1(N=24), 2 (N=20) and 3 (N=14). The sensitivities of J sign grades in predicting patellar instability were 45.8% (J1), 80% (J2), and 92.9% (J3) (p<0.01), with statistically significant differences between Grades 1 and 2/3 (0=0.018). Conclusion: On DKCT imaging, we noted additional patterns of patellar maltracking besides the standard J sign. Of those with maltracking in extension (J sign), Grade 2 and 3 J signs with > 2 quadrants of patellar lateralization in extension were predictive of symptomatic patellar instability. Further understanding of patellar maltracking patterns can provide the clinician with information regarding the pathoanatomy and pathophysiology of patellar instability, and allow us to better plan for surgical stabilization.

Concomitant compressive neuropathy of the ulnar and median nerves in the hand by midpalmar ganglion

Ganglia are the most common benign tumor lesions affecting the hand [4,12]. They are typically asymptomatic but can be associated with peripheral nerve compression in the upper extremity. Volar wrist ganglia are the most common cause of ulnar neuropathy originating at or below the wrist [8]. Ganglia of the carpometacarpal joints are also common but typically do not cause ulnar neuropathy [6]. Even more rare is a ganglion causing a concomitant compressive neuropathy of the median and ulnar nerve. Here, we describe a case of a ganglion cyst of the third carpometacarpal joint simultaneously associated with compression of both the deep motor branch of the ulnar nerve and the median nerve.

The Scleroderma Hand: Manifestations of Disease and Approach to Management

Scleroderma is a rare autoimmune connective tissue disorder that often affects the hands. Manifestations in the hands include calcium deposits within the soft tissues that cause pain and may ulcerate through the skin, digital ischemia resulting in chronic wounds and digital gangrene, and joint contracture. Because of the underlying disease, patients with scleroderma have poorly vascularized tissue and a deficient soft tissue envelope, which make surgery particularly challenging. However, when undertaken with care, surgical intervention is often the best option for addressing the disabling hand conditions that so often accompany this disease.

Calcific Tendinitis of the Gluteus Maximus in a Golfer.

Calcific tendinitis is a relatively rare condition in which calcium is inappropriately deposited in tendons, resulting in a local inflammatory reaction that can cause severe symptoms in certain cases. The cause of this disease process is not completely understood, although repetitive microtrauma likely plays a role in its development. Although the disorder most often involves the rotator cuff, it can affect other structures throughout the body, such as the tendons about the ankle and hip-including the rectus femoris and gluteus maximus. Nonoperative management typically involves using an anti-inflammatory medication and activity modification and can be augmented with formal physical therapy and modalities. Although nonoperative management provides adequate relief for many patients, sometimes operative debridement of the calcific deposit with or without repair of the involved tendon is required. The authors report an unusual case of calcific tendinitis of the gluteus maximus insertion in a golfer. The patient had tried nonoperative treatment for approximately 2 years with no real relief, and a recent exacerbation of the pain was significantly delaying his return to sport. Although plain radiographs did not show abnormalities, magnetic resonance imaging showed a calcific deposit in the insertion of the gluteus maximus tendon. After discussing further treatment options with the patient, the decision was made to remove the deposit and repair the insertion. He recovered completely and was able to return to play. The frequency, pathogenesis, and treatment of this condition are discussed in this case report, as well as the possible link to golf in this patient. [Orthopedics.2016; 39(5):e997-e1000.].