The effect of a pneumatic leg brace on return to play in athletes with tibial stress fractures.

A total of 18 competitive and recreational athletes were enrolled in a randomized, prospective study looking at the effect of pneumatic leg braces on the time to return to full activity after a tibial stress fracture. All patients had positive bone scans and 15 had positive radiographic findings by Week 12. There were two treatment groups. The traditional treatment group was treated with rest and, after 3 pain-free days, a gradual return to activity. The pneumatic leg brace (Aircast) group had the brace applied to the affected leg and then followed the same return to activity guidelines. The guidelines consisted of a detailed functional progression that allowed pain-free return to play. The brace group was able to resume light activity in 7 days (median) and the traditional group began light activity in 21 days (median). The brace group returned to full, unrestricted activity in 21 +/- 2 days, and the traditional group required 77 +/- 7 days to resume full activity. The Aircast pneumatic brace is effective in allowing athletes with tibial stress fractures to return to full, unrestricted, pain-free activity significantly sooner than traditional treatment.

Foot inversion-eversion and knee kinematics during walking.

The purpose of this study was to monitor selected aspects of the three-dimensional kinematics of the knee during walking with regular shoes and with modified shoes that induced either pronation or supination of the foot. Steinmann traction pins were inserted into the right tibia and femur of five adult men who had apparently normal lower extremities. Target clusters mounted onto the pins were filmed by four cine cameras operating at 100 frames/sec. Two trials per subject were analyzed for each of the three experimental conditions: regular running shoes, running shoes with a 10 degree valgus wedge, and running shoes with a 10 degree varus wedge. The different types of footwear induced only minor kinematic changes at the knee during the stance phase of walking. The angular patterns of the tibiofemoral joint were modified by less than 1 degree, whereas the translatory patterns were altered by 2 mm. Immediately following foot-strike, the valgus-wedge shoes caused the tibia to rotate internally 4 degrees more than the varus-wedge shoes, but at the tibiofemoral joint no consistent differences in the pattern of internal-external rotation between normal and modified footwear were measureable. These findings suggest that, in the healthy lower extremity, increased internal and external tibial rotation is resolved at the hip joint, with changes at the tibiofemoral joint that barely are detectable with the techniques used in this study.

The saphenous nerve: an external method for identifying its exit from the adductor canal.

The saphenous nerve is the largest and longest branch of the femoral nerve. At its proximal origin, it travels with the femoral artery. The nerve passes lateral to medial in the adductor canal to emerge subcutaneously and supply the medial side of the knee. This investigation analyzes the course of the nerve in 24 lower extremities (12 right, 12 left) and offers a standardized measuring system for externally pinpointing the nerve's exit from the canal. This study may benefit physicians who treat patients with knee pain of obscure etiology. It probably will have direct application to saphenous nerve injection by physicians as part of a pain-management program.

A comparison of patient-controlled analgesia and continuous lumbar plexus block after anterior cruciate ligament reconstruction.

Anterior cruciate ligament (ACL) reconstruction is often a painful operation. Fifty-eight patients who underwent ACL reconstruction using patellar tendon autograft received either a lumbar plexus block (LPB) or patient-controlled analgesia (PCA) for pain relief during the first 24 h after surgery. The average total dose of narcotic used was dramatically less for the LPB group (10.1 mg) than for the PCA group (91.9 mg). The common narcotic analgesic side effects of nausea, pruritus, sedation, and urinary retention were significantly less in the LPB group. The LPB is a safe and effective alternative analgesia after ACL reconstruction.

The Ellison iliotibial-band transfer for a torn anterior cruciate ligament of the knee. Long-term follow-up.

We studied the long-term results of the Ellison technique of extra-articular transfer of the iliotibial band, without advancement of the biceps tendon, as the sole operative treatment for a torn anterior cruciate ligament. Thirty-two patients (thirty-two knees) were evaluated an average of eleven years (range, seven to fifteen years) after the operation. The average age at the time of the operation was twenty-two years (range, sixteen to thirty-four years). Eighteen patients (56 per cent) had a modified Lysholm score of less than 84 points, indicating symptoms during the activities of daily living. Only six patients (19 per cent) had a subjectively normal knee (a modified Lysholm score of more than 94 points). The most common reason for a poor subjective score was the presence of symptoms of instability, in twenty-four patients (75 per cent). Twenty-four patients (75 per cent) had a positive pivot-shift test and twenty-nine patients (91 per cent), a positive Lachman test. Twelve patients (38 per cent) had severe (grade 3 or 4) radiographic changes. The radiographs of the knee appeared normal (grade 0) in only eight patients (25 per cent). There was a significant association between a meniscal injury and radiographic changes (p < 0.05). Fourteen patients (44 per cent) had subsequent procedures due to persistent instability or pathological changes in the articular cartilage or in a meniscus. There was a significant decline in the subjective and objective knee scores in the twenty-one patients who were evaluated at both two and eleven years. The number of patients who had a positive pivot-shift test increased from five (24 per cent) to sixteen (76 per cent). Subjectively, the number of patients who had a good result decreased from fourteen (67 per cent) to five (24 per cent). Objectively, nine patients (43 per cent) had a rating of good at two years; this fell to three (14 per cent) at eleven years. Symptomatic instability, pain, and a positive pivot-shift test were the most common reasons for a poor result. Because of the decline in the subjective and objective scores, we no longer recommend the Ellison procedure as the sole operative treatment for a torn anterior cruciate ligament of the knee.

Glenoid dysplasia. A case report and review of the literature.

Glenoid dysplasia is a rare congenital abnormality that may be associated with vague shoulder pain, limitation of motion, and weakness of the upper extremity. In many cases it is an incidental finding on chest roentgenogram, and high-level function is usually possible before the onset of symptoms or degenerative changes. The case of an 18-year-old collegiate football offensive lineman who developed symptoms secondary to previously undetected bilateral glenoid dysplasia is reported. Roentgenograms demonstrated dysplastic scapular necks, and arthrography showed a deformed, constricted shoulder capsule. Magnetic resonance imaging defined the extent of the cartilaginous anlage, and arthroscopy demonstrated progressive articular cartilage degeneration. Although treatment alleviated the shoulder symptoms at low-level activities, the patient was unable to successfully compete under the extreme demands of an American football lineman.

Fibular stress fracture associated with distal tibiofibular synostosis in an athlete. A case report and literature review.

A 19-year-old collegiate football player with progressive ankle syndesmosis ossification developed acute localized fibular tenderness. Roentgenograms demonstrated a fibular stress fracture proximal to the superior extent of the ossific mass. Surgical resection of the mass resulted in uneventful fibular healing, with resolution of acute and chronic symptoms.

Treatment of severe brain ischemia with di- and tri-Calciphor (dimer and trimer of 16,16'-dimethyl prostaglandin B1).

Following 20 min occlusion of both carotid arteries, female gerbils were subjected to treatment with di- or tri-Calciphor (dimer or trimer of 16,16'-dimethyl prostaglandin B1). Dimer was injected i.p. at 5 and 10 mg/kg at 5 min and again at 24 h, 30 min and 24 h, 60 min and 24 h or 180 min and 24 h postischemia (N = 25/group). Trimer was given i.p. at 5, 10 or 15 mg/kg at 5 min and 24 h postischemia (N = 25/group.) The controls (N = 25) were injected with the vehicle. Neurological status and postischemic survival of the animals were monitored for 14 days postischemia. Survival of the treated gerbils was significantly improved following the treatment with either di- or tri-Calciphor administered at 10 mg/kg at 5 min and 24 h postischemia (36 vs. 68% di- and 64% tri-Calciphor, P less than 0.05), and with di-Calciphor at 5 mg/kg at 180 min and 24 h postischemia (64%). All other treatment regimens with either drug resulted in a numerical, statistically insignificant improvement. In addition, treatment with either drug reduced the intensity of postischemic neurological impairment. Treatment with di-Calciphor injected at 10 mg/kg at 5 min and 24 h post 20 min ischemia substantially reduced the period of postischemic locomotor hyperactivity. The drug had no impact on either body temperature or blood pressure. There is evidence that the effects of Calciphor may be mediated via calcium regulatory mechanisms. The results of the present study are discussed in the light of such possibility.

Three-dimensional kinematics of the human knee during walking.

Three-dimensional kinematics of the tibiofemoral joint were studied during normal walking. Target markers were fixed to tibia and femur by means of intra-cortical traction pins. Radiographs of the lower limb were obtained to compute the position of the target markers relative to internal anatomical structures. High-speed cine cameras were used to measure three-dimensional coordinates of the target markers in five subjects walking at a speed of 1.2 m s-1. Relative motion between tibia and femur was resolved according to a joint coordinate system (JCS). The measurements have identified that substantial angular and linear motions occur about and along each of the JCS axes during walking. The results do not, however, support the traditional view that the so-called 'screw home' mechanism of the knee joint operates during gait.

Response of the electrochromic dye, merocyanine 540, to membrane potential in rat liver mitochondria.

Merocyanine binds extensively to rat liver mitochondria in spite of the presence of a sulfonic acid group which would suggest only limited penetration through the membrane. Passive binding shows both tight and weak binding components and is dependent on salt concentration and ionic strength in accord with the Gouy-Chapman theory. The binding of merocyanine to mitochondria is accompanied by both a fluorescence enhancement and a spectral shift. Induction of an electrical field by either respiration or K+ diffusion potential results in a partial reversal of the spectral shift seen on dye binding. At low temperature, the merocyanine spectral response to an electrical field is biphasic, consisting of a fast phase with a t1/2 of less than 1 sec at 15 degrees C and a slower phase which may vary considerably in rate and extent with conditions. The spectral shift during the two phases appears similar, but differ in sensitivity to ionic strength and temperature. The spectral shift during the fast phase at 15 degrees C indicates that the major component is a decrease in bound monomer and an increase in the aqueous dimer, indicating an "on-off" mechanism. It is suggested that the fast and slow phases of the merocyanine response may be due to two different populations of dye, possibly located at the outer and inner surfaces, respectively, of the mitochondrial membrane. The electrophoretic movement of the dye located in the membrane interior would result in the temperature-sensitive slow phase response. Demonstration of the proportionality of the fast phase response to the magnitude of the membrane potential suggests the usefulness of merocyanine in studies with mitochondrial systems.

Repair of peripheral meniscal tears: open versus arthroscopic technique.

Tears in the peripheral vascular zone of 71 menisci in 68 knees were repaired by us from 1978 to 1986. The meniscus repair was done by open arthrotomy in 26 cases and by arthroscopic techniques in 45 cases. We have assessed the relative efficacies of open and arthroscopic repair techniques. The results were compared in knees with and without anterior cruciate laxity. The indications for meniscal repair included unstable peripheral detachments and longitudinal tears of the outer third of the meniscus. Open repair was performed by a posteromedial arthrotomy incision. Arthroscopic repair was done using the double-lumen guide system with a limited posterior incision for retrieval of needles. We have found that the arthroscopic technique is easier to perform than the open repair because some tears are too far inside the rim to lend themselves to open suture. The average follow-up is 4 years, 2 months, with a range of 2-10 years. There have been no neurologic or vascular injuries from either technique. Twenty-five patients have had a repeat arthroscopy. The overall failure rate was 9.8%. The difference between the failure rate of 11% in the open-repair group and 8.8% in the arthroscopic repair group was not statistically significant. The failure rate in anterior cruciate-stable knees was 8% versus a 13% failure in cruciate-deficient knees. We conclude that both open and arthroscopic meniscus repair techniques are safe and effective with few complications in both stable and unstable knees. Anterior cruciate ligament stability is ideal, but it is not mandatory for a successful result.

Meniscus repair in the anterior cruciate deficient knee.

From 1979 to 1986, isolated repair of a peripheral vascular zone meniscal tear was performed in 22 patients (23 menisci) who had ACL insufficiency. For various reasons none of these patients underwent repair or reconstruction of their ACL. The meniscus repair was done by open arthrotomy in 12 cases and by arthroscopic techniques in 11 cases. The purpose of this study was to evaluate the success rate of a meniscal repair in an anterior cruciate deficient knee. The average age of the patients at the time of surgery was 25 years and the average followup was 56 months. Six patients (26%) had mild occasional pain not requiring medication and one patient had moderate pain requiring nonnarcotic pain medication. Eight patients (26%) had occasional giving way episodes and one of them underwent ACL reconstruction 5 years later because of frequent giving way. One patient required a postoperative manipulation for inadequate range of motion, but there were no neurovascular injuries or infections. There were three patients (13%) who had failed repairs or a retear and required subsequent subtotal meniscectomies. None of the other patients had any clinical symptoms or signs of a meniscal tear. There were no significant differences between the results of open or arthroscopic repair. Even though the failure rate of meniscus repair may be greater in an unstable knee, we conclude that meniscus repair is not contraindicated in an anterior cruciate deficient knee.

Isolated avulsion of the biceps femoris insertion. A case report.

The clinical, roentgenographic, and operative findings of an isolated biceps femoris avulsion in a 21-year-old man demonstrated the significance of the static stabilizers about the knee, menisci, and articular cartilage. Examination of the dynamic structures about the knee, however, may present a diagnostic problem. A systematic examination of the musculature (hamstrings, quadriceps, and patellofemoral mechanism) should be included in the evaluation of every acute knee injury. Special attention should be given to the surface anatomy as well as function of the knee.

Arthroscopy update #7. Alternative arthroscopic techniques for meniscus repair. A review.

Several treatment options and surgical techniques have evolved for treating vascular zone tears of the meniscus. The rationale and indications for meniscus repair are discussed, and a review of the various arthroscopic meniscal repair techniques is presented.

Saphenous nerve entrapment at the adductor canal.

A retrospective study of 30 patients who met the clinical criteria for saphenous nerve entrapment at the adductor canal is described. Patients experienced symptoms, usually anterior knee pain, for an average of 36 +/- 7 months. Each patient received an average of 1.9 +/- 0.4 saphenous nerve blocks at the adductor canal during treatment. Baseline pain level (measured by the visual analog scale) was 6.4 +/- 0.3. Final pain level at followup was significantly decreased (2.8 +/- 0.5, P less than 0.001). Eighty percent of patients had improved after a series of blocks. Age, medications taken, number of blocks performed, and length of followup were unrelated to outcome. Length of symptoms did significantly correlate with final pain level (r = 0.39, P less than 0.05). The diagnosis of this syndrome, description of the saphenous nerve block at the adductor canal, and the possible etiology are presented.

A requirement for cholesterol for phorbol ester-induced adhesion of a human monocyte-like cell line.

The human monocyte/macrophage-like cell line U937, which is a cholesterol auxotroph, is nonadherent. However, it becomes adherent after treatment with phorbol 12-myristate 13-acetate (phorbol ester). We investigated the effects of cellular cholesterol depletion and repletion on the effectiveness of phorbol ester to induce adhesion to substratum. Almost 70% of cellular cholesterol is depleted by incubation of the cells for 24 hrs in the growth medium in which delipidated fetal calf serum is substituted for fetal calf serum without affecting viability or the rate of growth. The use of delipidated fetal calf serum inhibited phorbol ester-induced adhesion by 40%. If the cells were preincubated in the medium containing delipidated fetal calf serum 6 hrs prior to addition of phorbol ester, adhesion was inhibited by 90%. Addition of cholesterol to the medium containing delipidated fetal calf serum, which replenishes cellular cholesterol, restored the ability of phorbol ester to induce adhesion to levels seen in cells cultured in the medium containing fetal calf serum. Epicholesterol was not as effective as cholesterol in supporting adhesion. Cholesterol depletion did not inhibit phorbol ester stimulation of superoxide anion production. These observations indicate a function for cholesterol in phorbol ester-induced adhesion that is independent of phorbol ester-induced superoxide anion production. It is proposed that cholesterol is required for synthesis and/or proper orientation and distribution, in the plasma membrane, of macromolecule(s) that mediate phorbol ester-induced adhesion.

Women athletes with menstrual irregularity have increased musculoskeletal injuries.

We have performed a retrospective three-phase study to evaluate the effect of menstrual status upon musculoskeletal injuries in women athletes. Initially, we collected the menstrual and running histories of women participants in a regional 10-km footrace. In this study, 61% of the respondents to our questionnaire reported a continuous running program, and 39% reported an interruption of at least 3 months of their running program. The most common cause for interruption was injury. Those who had interrupted their running were more likely to have had irregular or absent menses and less likely to have been using oral contraceptives than the group of continuous runners. Secondly, we obtained information on the relationship between bone injury and menstrual status by reviewing the sports medicine records of 207 collegiate women athletes. We found that X-ray-documented fractures occurred in 9% of women athletes with regular menses and in 24% of women athletes with irregular or absent menses. Subsequently, we collected data from a larger population of more serious, but still recreational runners, participating in a national 10-km race. Each portion of this study has yielded similar results: those women who had been injured during their running program were more likely to have had absent or irregular menses, were less likely to have used oral contraceptives, and had been running for more years. We conclude that premenopausal women who have absent or irregular menses, while engaged in vigorous exercise programs, are at increased risk for musculoskeletal injury.