A cause of ulnar neuropathy in a baseball pitcher

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66653/2/10.1177_036354658601400518.pd

Postoperative pulmonary edema in young, athletic adults

Pulmonary edema secondary to postextubation laryn gospasm is a potentially life-threatening problem, de manding early diagnosis and prompt treatment. We believe that this problem has been grossly underesti mated in its incidence, as only seven adults have been reported in the English literature, whereas seven adults have been observed at our institution in only a 24 month period. All were young, healthy, athletic adult males (average weight, 218 pounds) who underwent relatively minor, uncomplicated surgical procedures under gen eral anesthesia. Five of these patients were collegiate and/or profes sional athletes and had meticulous medical records detailing their clinical course. Clinical laryngospasm was noted immediately following extubation and anesthesia by mask with subsequent pulmonary edema. The di agnoses were confirmed by clinical examination, arterial blood gas determinations or pulse oximetry, and chest roentgenogram. Four adults required reintubation. Six of the seven adults demonstrated very rapid resolution of the pulmonary edema with prompt diagnosis and institution of a therapeutic regimen including oxygen, diuretics, reintubation, and/or positive pressure venti lation. In one patient, the problem was not immediately recognized, and progressed to florid pulmonary edema requiring emergent intubation 14 hours later in the emergency room, and 3 days of mechanical ventilation. The etiology of pulmonary edema following upper airway obstruction represents an interplay between several factors: cardiogenic and neurogenic mecha nisms, as well as hypoxia contribute. In this group, excessive negative intrathoracic pressure generated by forced inspiration against a closed glottis is the most likely, consistent, and logical explanation. This study suggests that young, healthy, athletic males may be at increased risk for this complication. We believe that their enhanced ability to generate ex cessive negative intrathoracic pressures is, at least in part, responsible. A heightened awareness of the prob lem in this at-risk group should invoke special consid erations, including choice of anesthesia, precautions on extubation, prolonged monitoring in the recovery phase if laryngospasm is observed or suspected, and rapid therapeutic intervention.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66519/2/10.1177_036354659101900407.pd

The Effect of Exercise, Prewrap, and Athletic Tape on the Maximal Active and Passive Ankle Resistance to Ankle Inversion

This investigation explored alternatives to the null hy potheses that maximal active and passive resistance to inversion developed by a near-maximally inverted and weightbearing ankle is not altered by 1) the use of prophylactic adhesive athletic tape, 2) the use of non- adhesive prewrap (underwrap), or 3) 40 minutes of vigorous exercise. Ten healthy men and 10 healthy women (mean age, 25 ± 3 years) with no recent ankle injuries underwent testing to determine maximal ankle resistance to inversion under unipedal, weightbearing conditions. Tests were performed with and without the support of athletic tape, and before and after 40 min utes of exercise. Half the testing sessions were per formed with prewrap under the tape. At 15° of inver sion, without any external ankle support, healthy young men and women could maximally resist a mean (SD) inversion moment of 52.9 (6.4) N-m and 28.3 (5.8) N-m, respectively. Although use of ankle tape provided a 10% increase in maximal resistance to inversion moments, this increase diminished to insignificant lev els after 40 minutes of vigorous exercise. Use of pre wrap improved maximal resistance to inversion by more than 10%.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66568/2/10.1177_036354659702500203.pd

Arthroscopic meniscal repair evaluated by second-look arthroscopy

Of 353 arthroscopic peripheral meniscal repairs per formed using the "outside to inside" suturing technique with rasp preparation of the tear region, 74 repairs (50 medial and 24 lateral) were assessed by second-look arthroscopy and are the basis of this report. Results were graded as either healed, incompletely healed, or failed; these findings were correlated with clinical symp toms and associated ACL deficiency. Overall, asymp tomatic healing occurred in 84%, with 65% healed and 19% incompletely healed. The failure rate was 16%. All failures were symptomatic while all healed and incom pletely healed menisci were asymptomatic. Failure was associated with ACL deficiency in all cases. No failures occurred in either an ACL uninjured knee or an ACL reconstructed knee. Failure was also associated with tear location in the posterior horn of the medial menis cus. Eleven of 12 failures (92%) involved posterior medial meniscal tears with only 1 failure located pos terolaterally. Visual evidence of healing required a 4 month time interval.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68119/2/10.1177_036354659101900614.pd

Applying Lean Techniques to Improve the Patient Scheduling Process

A patient's access to healthcare resources often begins with scheduling an appointment with a medical doctor or other provider. An inefficient scheduling system leads to unnecessary delays in providing care for patients and frustration for referring physicians. We used the tools of lean thinking to evaluate our current scheduling system, remove wasteful processes and procedures, and implement a more efficient and effective system. In doing so, we increased the value for our patients, who benefit from more timely access to care and greater satisfaction.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73944/1/j.1945-1474.2009.00025.x.pd

Quantitative analysis of the measuring capabilities of the KT-1000 knee ligament arthrometer

The KT-1000 arthrometer was evaluated in vitro and in vivo to determine accuracy and quantify effects of potential error sources in clinical application. The KT- 1000 arthrometer in vitro accuracy was evaluated by making 30 measurements of 13 known displacements (range, +15 to -15 mm). The effect of applied force on malalignment measurements was evaluated in vitro by making repeated measurements with force applied 5°, 10°, and 15° from the vertical position. The effect of malpositioning the device along the joint line was eval uated in vivo by making repeated measurements 1 cm proximal and 1 cm distal to the joint line. The KT-1000 arthrometer was accurate in vitro (average error, 0.13 mm; SD, 0.12 mm). The range of measurements in creased when the angle of force application was in creased. Positioning the device 1 cm proximal to the joint line produced larger anterior translation measure ments in vivo than those at the joint line (5.8 versus 5.4 mm), while positioning it 1 cm distal produced smaller measurements (4.4 mm). The KT-1000 arthrometer's accuracy indicates great potential for clinical applica tion, but one must ensure that the displacing force is directed properly and the device is positioned accu rately over the joint line.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66953/2/10.1177_036354659302100520.pd

A Statistics Primer

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67032/2/10.1177_036354659702500425.pd

A biomechanical evaluation of taping and bracing in reducing knee joint translation and rotation

We used five randomly selected cadaver specimens to evaluate the Anderson Knee Stabler and the Lenox Hill Knee Brace, individually and in combination with an anterior cruciate ligament protective tape method. Re duction of total laxity, as well as a defined pathologic anterior-posterior translation and internal-external ro tation, was tested after the anterior cruciate and medial collateral ligaments of the specimens had been sec tioned. Displacements were produced pneumatically; loads were applied to the tibia with the knee in 50° of flexion. The tape and Lenox Hill Brace combination showed the greatest reduction in both anterior-posterior trans lation and internal-external rotation. The Lenox Hill Brace and the tape method used individually both re stricted anterior-posterior translation and internal-ex ternal rotation better than the Stabler Brace alone. This study provides objective evidence of the restraining capabilities of these protective systems that may prove to be beneficial in the clinical setting.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67165/2/10.1177_036354659202000409.pd

New perspectives on ACL injury: On the role of repetitive subâ maximal knee loading in causing ACL fatigue failure

In this paper, we review a series of studies that we initiated to examine mechanisms of anterior cruciate ligament (ACL) injury in the hope that these injuries, and their sequelae, can be better prevented. First, using the earliest in vitro model of a simulated singleâ leg jump landing or pivot cut with realistic knee loading rates and transâ knee muscle forces, we identified the worstâ case dynamic knee loading that causes the greatest peak ACL strain: Combined knee compression, flexion, and internal tibial rotation. We also identified morphologic factors that help explain individual susceptibility to ACL injury. Second, using the above knee loading, we introduced a possible paradigm shift in ACL research by demonstrating that the human ACL can fail by a sudden rupture in response to repeated subâ maximal knee loading. If that load is repeated often enough over a short time interval, the failure tended to occur proximally, as observed clinically. Third, we emphasize the value of a physical exam of the hip by demonstrating how limited internal axial rotation at the hip both increases the susceptibility to ACL injury in professional athletes, and also increases peak ACL strain during simulated pivot landings, thereby further increasing the risk of ACL fatigue failure. When training atâ risk athletes, particularly females with their smaller ACL crossâ sections, rationing the number and intensity of worstâ case knee loading cycles, such that ligament degradation is within the ACL’s ability to remodel, should decrease the risk for ACL rupture due to ligament fatigue failure.© 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2059â 2068, 2016.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135588/1/jor23441.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135588/2/jor23441_am.pd

Magnetic resonance imaging of knee hyaline cartilage and intraarticular pathology

Injuries to the hyaline cartilage of the knee joint are difficult to diagnose without invasive techniques. Even though these defects may be the most important prog nostic factors in assessing knee joint injury, they are usually not diagnosed until arthrotomy or arthroscopy. Once injuries to hyaline cartilage are found and/or treated, no technique exists to follow these over time. Plain radiographs, arthrograms, and even computed tomography fail to detail most hyaline cartilage defects. We used magnetic resonance imaging (MRI) to eval uate five fresh frozen cadaver limbs and 10 patients whose pathology was known from arthrotomy or ar throscopic examination. Using a 0.35 Tesla supercon ducting magnet and spin-echo imaging technique with a head coil, we found that intraarticular fluid or air helped to delineate hyaline cartilage pathology. The multiplane capability of MRI proved to be excellent in detailing small (3 mm or more) defects on the femoral condyles and patellar surface. Cruciate ligaments were best visualized on sagittal oblique projections while meniscal pathology was best seen on true sagittal and coronal projections. MRI shows great promise in providing a noninvasive technique of evaluating hyaline cartilage defects, their response to treatment, and detailed anatomical infor mation about cruciate ligaments and menisci.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67078/2/10.1177_036354658701500505.pd