Superior labral anterior posterior (SLAP) lesions of the glenoid labrum: reliability and accuracy of MR arthrography for diagnosis.

PURPOSE: To determine the reliability and accuracy of magnetic resonance (MR) arthrography for the diagnosis of superior labral anterior posterior (SLAP) tears. MATERIALS AND METHODS: The MR arthrograms in 80 patients who underwent arthroscopy and MR arthrography during a 54-month period were retrospectively reviewed. MR arthrograms were independently scored by three observers for the presence and type of SLAP lesion. Type I SLAP lesions were regarded as negative as they most often are not clinically relevant. Interobserver agreement for detection of SLAP lesions was calculated by using kappa coefficients. The differences in areas under the receiver operating characteristic (ROC) curves were assessed with a univariate z score test. RESULTS: At arthroscopy, there were 25 SLAP tears: type II (n = 22), type III (n = 2), and type IV (n = 1). Sensitivity, specificity, and accuracy of each reader were 92%, 84%, and 86%; 92%, 82%, and 85%; and 84%, 69%, and 74%, respectively. Interobserver agreement for SLAP tears was substantial (kappa = 0.77) to moderate (kappa = 0.52, kappa = 0.44). The areas under the ROC curves for each reader were 0.94, 0.93, and 0.83, which were not significantly different. CONCLUSION: MR arthrography of the shoulder is reliable and accurate for detection of SLAP tears.

Regional anesthesia in knee arthroscopy: a new technique involving femoral and sciatic nerve blocks in knee arthroscopy.

We describe a new anesthetic technique of femoral and sciatic nerve blocks in knee arthroscopy. The sciatic nerve block is administered through a posterior approach, and the block of the femoral and lateral femoral cutaneous nerves in a single anterior approach. This type of regional anesthesia is safe and effective, providing excellent intraoperative and postoperative analgesia as well as minimizing postoperative complications.

Electromyographic analysis of the hip and knee during the golf swing.

As golf increases in popularity, more golfers seek the proper mechanics necessary for the perfect golf swing. Surprisingly little scientific work has been published on the contribution of the hip and knee muscles during the golf swing even though most professionals have recognized their vital contribution. Recent studies have described the electromyographic (EMG) muscle activity of the shoulder, back, and trunk during the golf swing. The purpose of this study was to describe the electrical muscle activity in seven hip and knee muscles of both the left (lead) and right (trail) leg in competitive golfers while performing the golf swing. Sixteen golfers were studied with indwelling electrodes and high-speed cinematography. The EMG was synchronized with the film to discern five phases of the golf swing. Means, SDs, and t-tests were done. The results revealed that the trail hip extensors and abductors in conjunction with the lead adductor magus initiated pelvic rotation during forward swing. The lead hamstrings maintained a flexed knee and provided a stable base on which pelvic rotation took place. The peak EMG muscle activity recorded in the hips and knees occurred in an earlier phase than that measured previously in the trunk and shoulder. This confirmed the sequential firing pattern of the hip and knee muscles that takes place during the competitive golf swing. Information gained from this study can be used by players and coaches to optimize performance and to minimize injury.

The effect of intraarticular injection of morphine and bupivacaine on postarthroscopic pain control.

This study sought to compare the effects of morphine, bupivacaine, and saline injected into the knee after arthroscopic surgery. In a double-blind, randomized trial, 124 patients received either bupivacaine, morphine, bupivacaine and morphine, or saline at the completion of surgery. Postoperative pain was assessed with a 100-mm visual analog pain scale. Analgesic requirements were calculated, and weightbearing status was recorded. We found that morphine alone injected intraarticularly at the completion of arthroscopic knee surgery had no significant effect on postoperative pain, need for supplemental analgesia, or weightbearing status. Patients receiving morphine in combination with bupivacaine did not demonstrate any statistically significant improvement over those receiving bupivacaine alone. Therefore, our results failed to show any beneficial effect of morphine used for postoperative analgesia, either alone or in combination with bupivacaine. The overall pattern in all patients demonstrated decreased pain scores, decreased analgesic use, and increased weightbearing status as the observation period progressed. Finally, preoperative pain was correlated with pain at discharge, indicating that the most significant predictor of postoperative pain was preoperative level of discomfort.

The normal and the painful shoulders during the breaststroke. Electromyographic and cinematographic analysis of twelve muscles.

The purpose of this study was to describe and compare electrical activity patterns in 12 shoulder muscles during the breaststroke in 25 competitive swimmers who had normal shoulders and in 14 who had painful shoulders while they performed this stroke in a pool. The electromyographic analysis was synchronized with high-speed cinematography to discern phases of the breaststroke. Means, standard deviations, and t-tests were done for each phase. The differences in muscle activity between the two groups of swimmers demonstrated an increase in the internal rotators in the group with painful shoulders. They also demonstrated a decrease in the teres minor, supraspinatus, and the upper trapezius muscles. These factors increase the risk of impingement. Both the serratus anterior and teres minor muscles in the swimmers with normal shoulders consistently fired at or above 15% manual muscle test throughout the breaststroke cycle and were thus subject to fatigue. Based on these results, exercises for the breaststroke swimmer should be directed toward endurance training of the serratus anterior and teres minor muscles while balancing the internal and external rotators of the shoulder as well as the deltoid and supraspinatus muscles.

Cost effectiveness of magnetic resonance imaging of the knee.

When compared to diagnostic arthroscopy in patients with knee complaints consistent with internal derangement, MR imaging emerges as a cost effective diagnostic supplement to clinical examination. This article concludes that the results of MR imaging can be used as a guide for the management of knee pain.

Pilon fractures of the distal tibia.

Pilon fractures are relatively rare fractures of the distal metaphysis of the tibia resulting from axial and/or rotational forces. They involve varying degrees of metaphyseal disruption, articular damage, and malleolar displacement. When severe, these injuries represent a tremendous challenge to the orthopaedic trauma surgeon. Traditional treatment of high-grade pilon fractures by closed means has led to unsatisfactory results. Open reduction and internal fixation in accordance with AO/ASIF principles has greatly improved the outcome in these often disabling fractures. Surgical technique involves anatomic restoration of fibular length, reconstruction of the plafond, bond grafting of the metaphyseal defect, and buttress plating of the medial tibia. Thorough preoperative planning and meticulous surgical technique produce predictably good results in the majority of cases.

Clinical determination of femoral anteversion. A comparison with established techniques.

We evaluated femoral anteversion preoperatively in fifty-nine patients (ninety-one hips), using a clinical method that we developed, Magilligan radiographs, and computed tomographic scans. These measurements were then compared with values for anteversion that were obtained intraoperatively. To determine femoral anteversion clinically, the patient was placed in the prone position and the maximum lateral trochanteric prominence was related to the degree of internal rotation of the hip. Compared with computed tomographic scanning and Magilligan radiographic determination, the clinically determined anteversion correlated most closely (to within 4 degrees) with the amount measured at the time of the operation. The clinical method was found to be superior to radiographic techniques for determination of the degree of femoral anteversion in children who have not had a previous operation about the hip.

Can MR imaging effectively replace diagnostic arthroscopy?

A study was performed to determine whether magnetic resonance (MR) imaging is cost-effective and reduces the need for diagnostic arthroscopy of the knee. During a 9-month period, 103 consecutive patients with knee injury that justified diagnostic arthroscopy underwent MR imaging. The MR images were interpreted by means of consensus of three radiologists and reviewed with the referring sports medicine orthopedists. After the examination, 44 patients (42.7%) underwent immediate arthroscopy. The 59 other patients (57.3%) did not undergo arthroscopy; follow-up was performed in 55 of these 59 patients (93%) at a mean of 22 months. The outcome was successful in 49 of 55 patients (89%); 40 patients had normal function and no limitation in activity, six patients with chronic injury of the anterior cruciate ligament underwent reconstruction, and three patients underwent arthroscopy with negative findings. Without the use of MR imaging, all patients in this study would have undergone diagnostic arthroscopy. Because of the diagnoses based on MR images, 53 patients (51.4%) avoided a potentially unnecessary diagnostic arthroscopy, and, as a result, the net savings was $103,700 in the 103 patients.

Effect of maternal fasting on fetal and placental lipid metabolism in swine.

This experiment was designed to determine whether mobilizing maternal energy stores by fasting pregnant gilts would promote fetal energy storage by altering placental and fetal lipid metabolism. Pregnant gilts were fed a 15% tallow diet from d 80 to 99 and then fed a basal high-carbohydrate diet (control) or fasted from d 100 to 110 of gestation. Caesarean section was performed on d 110. Fasting caused maternal nonesterified fatty acid (NEFA) levels to increase 7.5-fold, beta-hydroxybutyric acid (beta-HBA) levels to increase 4.8-fold triglyceride (TG) levels to decrease 1.8-fold, and no change in plasma glucose concentration compared with controls. Fasted fetuses had a 1.3-fold increase in NEFA, 1.9-fold decrease in TG, 1.5-fold decrease in glucose, and no change in beta-HBA levels compared with control fetuses. Distribution of NEFA in fetal plasma was different from distribution of NEFA in maternal plasma. Esterification of [14C]-palmitate by maternal placenta and fetal adipose tissue was reduced by fasting, but other parameters of fatty acid metabolism were unaffected. Fasting decreased lipoprotein lipase activity per milligram of protein by 33% in maternal placenta and by 44% in fetal adipose tissue. Glycogen content of fetal liver and skeletal muscle was reduced by fasting pregnant gilts, but there was no detectable effect on percentage of carcass lipid of the fetus. These data suggest that fasting mobilizes maternal fuel stores but that these stores are not effectively used by the placenta or transported to the fetus for storage.

Familial incidence of Paget's disease and secondary osteogenic sarcoma. A report of three cases from a single family.

This report describes a family of three siblings with a long history of polyostotic Paget's disease. Because of the severe osseous involvement with Paget's disease, all three patients had problems that required orthopedic surgery. Subsequent to these surgeries, two patients developed osteogenic sarcoma at sites unrelated to their past procedures, one in the sacrum and one in the calvarium. Both patients died shortly after their diagnosis because of the aggressive spread of the tumor. Although the etiology of Paget's disease and its complication of osteogenic sarcoma still remain to be clarified, this and other case reports suggest a possible environmental or hereditary contribution to developing osteogenic sarcoma in Paget's disease. Patients with a familial clustering of polyostotic Paget's disease may benefit from more thorough screening tests to detect malignant transformation.

Comparison of the effects of dietary glucose versus galactose on porcine feto-placental glucose metabolism.

The present study was conducted to determine whether dietary galactose can be used to improve glycogen and lipid accretion in fetal pigs. Pregnant gilts were fed diets containing either 24% glucose (control) or 24% galactose from d 98 to 110 of gestation. Gilts underwent abdominohysterotomy on d 110 of gestation. Slices of fetal subcutaneous adipose tissue and placenta were examined for metabolic capacity for glucose and for galactose utilization. No effects of maternal diet were evident upon glycogen content or enzyme activity of fetal semitendinosus muscle and liver. Maternal dietary galactose had no direct effects upon placental glucose oxidation or use for lipid synthesis. However, galactose supplementation of the incubation medium caused reductions in glucose oxidation (15%) and total lipid synthesis (24%) by the maternal placenta. Maternal dietary galactose caused an increase in total lipid (50%) and fatty acid synthesis (200%) from glucose in fetal subcutaneous adipose tissue; direct supplementation of galactose to the incubation medium had no effect on these parameters. The results of the present study suggest that feeding galactose to the pregnant gilt does not have direct effects upon placental metabolism or fetal glycogen storage. However, these data indicate that use of galactose in the maternal diet can result in an increase in the utilization of glucose for lipogenesis by fetal adipose tissue in swine. This effect is not a direct effect of galactose because transport across the placenta was not apparent.

A functional evaluation of cryopreserved peripheral nerve autografts.

This study compared the functional return following the repair of a 2.0-cm defect in the rat sciatic nerve with frozen (with or without treatment with a cryoprotectant, dimethyl sulfoxide [DMSO]) or fresh nerve grafts. In addition, a control group in which the defect was left ungrafted was evaluated. Recovery was assessed by functional studies (sensory testing, gait analysis, joint contractures, and tibialis anterior muscle weight), biochemical analysis (muscle hydroxyproline concentration), and histologic studies (axonal counts and fiber density). Sensory testing and gait analysis were not helpful because of cross-over innervation of the saphenous nerve and lack of recovery of the foot intrinsic muscles, respectively. The hind-limb contractures of the group with fresh nerve grafts (18 degrees +/- 3 degrees) were similar to those with DMSO-cryopreserved grafts (14 degrees +/- 4 degrees). Both of these groups had statistically smaller contractures than the non-DMSO-cryopreserved group (45 degrees +/- 8 degrees) and the gap control group (49 degrees +/- 6 degrees), (p less than 0.01). The tibialis anterior (TA) muscle-weight ratio (MWR) and the muscle-hydroxyproline-concentration ratio (MHPCR) showed a similar pattern, with no significant difference between the fresh (MWR, 0.5785 +/- 0.068 and MHPCR, 1.527 +/- 0.405) and DMSO-cryopreserved (MWR, 0.5675 +/- 0.0989 and MHPCR, 1.660 +/- 0.456) groups; both of these groups showed greater neurologic recovery when compared to the non-DMSO-cryopreserved (MWR, 0.3364 +/- 0.0266 and MHPCR, 3.441 +/- 0.300) and gap control (MWR, 0.2134 +/- 0.0775 and MHPCR, 4.869 +/- 2.351) groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Paget's disease in the hand: correlation of magnetic resonance imaging with histology.

A 62-year-old white woman was seen initially with a 4-month history of swelling over the dorsum of her wrist and thumb pain at the basal joint. Radiographs revealed pantrapezial arthritis and a marked increase in the radiodensity of the capitate. Tomograms showed slight enlargement of the capitate, and magnetic resonance imaging revealed a dramatic decrease in the signal intensity on T1- and T2-weighted images. A biopsy of the capitate was done at the time of thumb carpometacarpal joint arthroplasty. Active Paget's disease was diagnosed. It is postulated that loss of marrow fat in active Paget's disease decreased the T1- and T2-weighted signals in a manner similar to processes, such as Gaucher's disease and osteonecrosis.

The effect of tourniquet pressure on muscle function.

The adverse effects of excessive tourniquet pressure on underlying muscle were studied using a cat model. A direct effect of the magnitude of tourniquet pressure on the degree of muscle disability was observed. The effect of direct pressure on the muscle may contribute to the postoperative weakness seen in the quadriceps muscle. Our data, in conjunction with the results of other studies that correlate certain tourniquet times and pressures with potential adverse effects, suggest that the selection of an appropriate tourniquet pressure and duration will minimize the development of clinically significant complications.

Refracture of bones of the forearm after the removal of compression plates.

Of thirty-seven patients who had sixty-two diaphyseal plates removed from the forearm after fixation of a fracture, seven patients had a refracture, two of whom refractured both bones of the forearm. Six of the seven refractures were in patients who initially had had a fracture of both bones, and all were in patients in whom the original fracture had been caused by major trauma. The interval from the time of removal of the plate to refracture ranged from forty-two to 121 days. Only one of the seven patients who had a refracture had had adequate compression of the original fracture. The average interval from the time of the original trauma to internal fixation was two days in six patients who had a refracture and who originally had had primary plating, compared with 8.5 days in the patients who did not have a refracture. One of the seven patients who had a refracture had originally had delayed plating after closed treatment had failed. In retrospect, radiolucency at the site of the original fracture was seen in most patients when the plate was removed.