Video analysis of trunk and knee motion during non-contact anterior cruciate ligament injury in female athletes: lateral trunk and knee abduction motion are combined components of the injury mechanism.

BACKGROUND: The combined positioning of the trunk and knee in the coronal and sagittal planes during non-contact anterior cruciate ligament (ACL) injury has not been previously reported. HYPOTHESIS: During ACL injury female athletes demonstrate greater lateral trunk and knee abduction angles than ACL-injured male athletes and uninjured female athletes. DESIGN: Cross-section control-cohort design. METHODS: Analyses of still captures from 23 coronal (10 female and 7 male ACL-injured players and 6 female controls) or 28 sagittal plane videos performing similar landing and cutting tasks. Significance was set at p < or = 0.05. RESULTS: Lateral trunk and knee abduction angles were higher in female compared to male athletes during ACL injury (p < or = 0.05) and trended toward being greater than female controls (p = 0.16, 0.13, respectively). Female ACL-injured athletes showed less forward trunk lean than female controls (mean (SD) initial contact (IC): 1.6 (9.3) degrees vs 14.0 (7.3) degrees, p < or = 0.01). CONCLUSION: Female athletes landed with greater lateral trunk motion and knee abduction during ACL injury than did male athletes or control females during similar landing and cutting tasks. CLINICAL RELEVANCE: Lateral trunk and knee abduction motion are important components of the ACL injury mechanism in female athletes as observed from video evidence of ACL injury.

Retrospective report on the effectiveness of a polyurethane football helmet cover on the repeated occurrence of cerebral concussions.

This report reviews the literature and unpublished data and presents survey results related to the use of a polyurethane football helmet cover. Two hundred forty-five individuals, identified by the helmet manufacturer as having purchased at least one device, were sent a survey after the 1992, 1993, and 1994 football seasons; 155 (63.3%) of the surveys were returned. The questionnaire, designed to be completed by the athlete, required a detailed history of concussions occurring both prior to and during the period the device was used. Individuals used the device as a result of having incurred at least one concussion. Rates of concussion reoccurrence while the device was worn were grouped by the number of previous concussions (1, 2, 3, or 4+) that occurred over a 4year period prior to use of the device. The rate of concussion reoccurrence was 2.4%, 7.3%, 15.8%, and 33.3%, respectively, over a 4-year period. The range appeared to reflect a parallel relationship between pre- and post-device concussion experiences: the more concussions experienced prior to adopting the device, the higher the rate of concussion reoccurrence while using the device. The natural history of repeated occurrences of concussive events may not be affected by the use of a polyurethane football helmet cover. We suggest that such a device not be routinely used prophylactically, but instead be reserved for individuals with 1 to 2 prior concussion injuries. However, at this time, we neither recommend nor discommend the device.

The search for the Holy Grail: a century of anterior cruciate ligament reconstruction.

A perspective on the history of the development of anterior cruciate ligament reconstruction is presented. The lack of critical analyses establishing the relative effectiveness of many previously described procedures is documented.

Cervical cord neurapraxia: classification, pathomechanics, morbidity, and management guidelines.

One hundred ten cases of the transient neurological phenomenon, cervical cord neurapraxia (CCN), are presented. The authors established a classification system for CCN, developed a new computerized measurement technique for magnetic resonance (MR) imaging, investigated the relationship of the cervical cord to the canal, and analyzed clinical, x-ray, and MR data. One hundred nine males and one female were included in the study; the average age of the participants was 21 years (range 13-33 years). All episodes occurred during sports participation; 87% occurred while the patient was playing football. Follow-up review lasting an average of 3.3 years was available for 105 patients (95%). Narrowing of the sagittal diameter of the cervical canal in the adult spine was confirmed to be a causative factor. Cervical cord neurapraxia was not associated with permanent neurological injury and no permanent morbidity occurred in patients who returned to contact activities. Of the patients returning to contact activities, 35 (56%) experienced a recurrent episode. The risk of recurrence was increased with smaller spinal canal/vertebral body ratio (p < 0.05), smaller disc-level canal diameter (p < 0.05), and less space available for the cord (p < 0.05). There was no correlation between either the classification of the CCN episode or the disease noted on MR imaging and x-ray films and the risk of recurrence. The authors conclude that: 1) CCN is a transient neurological phenomenon and individuals with uncomplicated CCN may be permitted to return to their previous activity without an increased risk of permanent neurological injury; 2) congenital or degenerative narrowing of the sagittal diameter of the cervical canal is a causative factor; 3) the overall recurrence rate after return to play is 56%; and 4) the risk of recurrence is strongly and inversely correlated with sagittal canal diameter and it is useful in the prediction of future episodes of CCN (p < 0.001). These data will enable the physician to counsel individuals regarding a predicted risk of recurrence based on canal measurements.

Management guidelines for participation in collision activities with congenital, developmental, or postinjury lesions involving the cervical spine.

OBJECTIVE: Conditions involving the cervical spine in athletes requiring a management decision are numerous. This report presents appropriate guidelines for return to collision activities in those with congenital, developmental, or postinjury lesions. DATA SOURCES: Information was compiled from > 1,200 cervical spine lesions documented by the National Football Head and Neck Injury Registry and an extensive literature review. DATA SYNTHESIS: Available data as well as a clinical understanding of injury mechanisms have resulted in the development of reasonable management guidelines. Each of the congenital, developmental, and posttraumatic conditions presented are determined to present either no contraindication, relative contraindication, or an absolute contraindication to sport participation on the basis of a variety of parameters. Conditions included in the discussion are odontoid anomalies; spina bifida occulta; atlanto-occipital fusion; Klippel-Feil anomalies; cervical canal stenosis; spear tackler's spine; traumatic conditions of the upper, middle, and lower cervical spine, including ligamentous injuries and fractures; intervertebral disc injuries; and postcervical spine fusion. CONCLUSION: The proposed guidelines should be used in the decision-making process in conjunction with other such factors as the age, experience, ability of the individual, level of participation, and position played, as well as the attitude and desires of the athlete and his or her parents following an informed discussion of the problem with particular regard to potential risk.

Management guidelines for participation in collision activities with congenital, developmental, or post-injury lesions involving the cervical spine.

We believe that the aforementioned management guidelines for participation in collision activities for individuals with congenital, developmental, or postinjury lesions involving the cervical spine have been formulated on the basis of the best information available to date. It is recognized that modifications may occur as more data are collected. We emphasize that these proposed guidelines should be used in the decision-making process in conjunction with such other factors as age, experience, ability of the individual, level of participation, and position played. A most important consideration is the attitude and desire of the individual and his parents following an informed discussion of the problem with particular regard to potential risks.

Suggested management guidelines for participation in collision activities with congenital, developmental, or postinjury lesions involving the cervical spine.

Many conditions involving the cervical spine in the athlete require a management decision. The purpose of this paper is to present appropriate guidelines for return to collision activities in those with congenital, developmental, or post-injury lesions. Information compiled from over 1200 cervical spine lesions documented by the National Football Head & Neck Injury Registry, an extensive literature review, as well as an understanding of injury mechanisms have resulted in reasonable management guidelines. Each of the congenital, developmental, and post-traumatic conditions presented are determined to present either no contraindication, relative contraindication, or an absolute contraindication on the basis of a variety of parameters. Conditions included in the discussion are: odontoid anomalies; spina bifida occulta; atlanto-occipital fusion; Klipple-Feil anomalies; cervical canal stenosis; spear tackler's spine; and traumatic conditions of the upper, middle, and lower cervical spine, including ligamentous injuries and fractures, intervertebral disc injuries, and post-cervical spine fusion. Emphasized is the fact that the proposed guidelines should be used in the decision-making process in conjuction with other factors such as the age, experience, ability of the individual, level of participation, position played, as well as the attitude and desires of the athlete and his parents after an informed discussion of the problem with particular regard to potential risk.

The pathomechanics of chronic, recurrent cervical nerve root neurapraxia. The chronic burner syndrome.

This study defined chronic recurrent cervical nerve root neurapraxia, the chronic burner syndrome, characterized the clinical findings, and described the responsible pathomechanics. We studied a subset of 55 athletes (mean age, 22 years) for evaluation of recurrent burners. Eleven subjects were professional athletes. The mechanism of injury was extension combined with ipsilateral-lateral deviation in 46 patients (83%). Spurling's sign was positive in 39 patients (70%). Twenty-nine patients (53%) had developmentally narrowed cervical canals, and 48 patients (87%) had evidence of disk disease by magnetic resonance imaging. The disk disease was in the form of a disk bulge, disk protrusion, or a frank disk herniation deforming the cord. Fifty-one patients (93%) had disk disease or narrowing of the intervertebral foramina secondary to degenerative disk disease. Although burners may be the result of a brachial plexus stretch injury in high school and collegiate football players seen with acute symptoms, nerve root compression in the intervertebral foramina secondary to disk disease is a more common cause in collegiate and professional players who have recurrent or chronic burner syndromes. There is a high incidence of cervical canal stenosis in football players with recurrent burner syndrome. The combination of disk disease and cervical spinal canal stenosis may lead to an alteration in normal cervical spine mechanics that may make these athletes more prone to chronic burner syndromes.

Cervical Spine and Brachial Plexus Injuries: Return-to-Play Recommendations.

Great care is required in managing cervical spine and brachial plexus injuries. Athletes who suffer one or more burners (transient brachial plexus injuries) may return to contact activity when they are asymptomatic and neurologically normal and have full cervical motion. A vertebra displaced horizontally more than 3.5 mm or rotated more than 11 degrees is an absolute contraindication to contact sports. Cervical cord neurapraxia is generally benign, but patients should be counseled about the probability of recurrence, depending on the spinal canal/vertebral body ratio. Unresolved spear tackler's spine is an absolute contraindication to collision sports, as are axial-load teardrop fracture and cervical spine fusion of more than three levels. Spinal cord resuscitation can include blood pressure maintenance and timely methylprednisolone.

Management guidelines for participation in collision activities with congenital, developmental, or post-injury lesions involving the cervical spine.

Conditions involving the cervical spine in the athlete requiring management decisions are numerous. The purpose of this paper is to present appropriate guidelines for return to collision activities in those with congenital, developmental, or post-injury lesions. Collision activities include boxing, football, ice hockey, lacrosse, rugby and wrestling. Information compiled from over 1200 cervical spine lesions documented by the National Football Head and Neck Injury Registry, an extensive literature review, as well as an understanding of injury mechanisms have resulted in reasonable management guidelines. Each of the congenital, developmental and post-traumatic conditions presented are identified as either no contraindication, relative contraindication, or an absolute contraindication on the basis of a variety of parameters. Conditions involved in the discussion include: odontoid anomalies, spina bifida occulta, atlanto-occipital fusion, K1ippel-Feil syndrome, cervical canal stenosis, spear tackler's spine; and traumatic conditions of the upper, middle and lower cervical spine including ligamentous injuries and fractures, intervertebral disc injuries and post-cervical spine fusion. It should be emphasized that the proposed guidelines should be used in the decision making process and in conjunction with other such factors as age, experience, ability of the individual, level of participation, position played, as well as the attitude and desires of the athlete and his parents, where applicable following an informed discussion of the problem with particular regard to potential risk.

Long-term evaluation of the Elmslie-Trillat-Maquet procedure for patellofemoral dysfunction.

We evaluated 55 knees in 51 patients after Elmslie-Trillat-Maquet procedures. The procedure involves medialization of the tibial tubercle on a distal pedicle and elevating the tibial tubercle anteriorly 10 mm with a local bone graft. At a mean followup of 74.2 months (range 13 to 196), all patients completed postoperative surveys and 38 underwent postoperative examinations. Subjectively, 9 knees (16%) had excellent results, 24 knees (44%) obtained good results, and 13 knees (24%) had fair results for a total of 84% improvement overall. Using Fulkerson's functional knee score, 19 knees (35%) had excellent results, 10 knees (18%) had good results, and 11 knees (20%) had fair results for a total of 73% improvement overall. A total of 24 knees (44%) required later screw removal. The most significant findings of this study include 1) an 84% overall subjective improvement in symptoms; 2) the findings that young patients without evidence of progressive osteoarthrosis and with patella instability as a primary symptom tend to have the most favorable outcome; and 3) 24 knees (44%) required later screw removal.

The relationship of developmental narrowing of the cervical spinal canal to reversible and irreversible injury of the cervical spinal cord in football players.

An evaluation of forty-five athletes who had had an episode of transient neurapraxia of the cervical spinal cord revealed a consistent finding of developmental narrowing of the cervical spinal canal. The purpose of the present epidemiological study was to determine the relationship, if any, between a developmentally narrowed cervical canal and reversible and irreversible injury of the cervical cord with use of various cohorts of football players as well as a large control group. Cohort I comprised college football players who were asymptomatic and had no known history of transient neurapraxia of the cervical cord. Cohort II consisted of professional football players who also were asymptomatic and had no known history of transient neurapraxia of the cervical cord. Cohort III was a group of high-school, college, and professional football players who had had at least one episode of transient neurapraxia of the cervical cord. Cohort IV comprised individuals who were permanently quadriplegic as a result of an injury while playing high-school or college football. Cohort V consisted of a control group of male subjects who were non-athletes and had no history of a major injury of the cervical spine, an episode of transient neurapraxia, or neurological symptoms. The mean and standard deviation of the diameter of the spinal canal, the diameter of the vertebral body, and the ratio of the diameter of the spinal canal to that of the vertebral body were determined for the third through sixth cervical levels on the radiographs for each cohort. In addition, the sensitivity, specificity, and positive predictive value of a ratio of the diameter of the spinal canal to that of the vertebral body of 0.80 or less was evaluated. The findings of the present study demonstrated that a ratio of 0.80 or less had a high sensitivity (93 per cent) for transient neurapraxia. The findings also support the concept that symptoms may result from a transient reversible deformation of the spinal cord in a developmentally narrowed osseous canal. The low positive predictive value of the ratio (0.2 per cent) however, precludes its use as a screening mechanism for determining the suitability of an athlete for participation in contact sports. Developmental narrowing of the cervical canal in a stable spine does not appear to predispose an individual to permanent catastrophic neurological injury and therefore should not preclude an athlete from participation in contact sports.

Analysis of failed surgical management of fractures of the base of the fifth metatarsal distal to the tuberosity: the Jones fracture.

Failure of surgical management of fractures of the base of the fifth metatarsal distal to the tuberosity is uncommon. Only one such failure has been reported in the literature to date. The purpose of this article is to present the clinical course of 11 patients with failure of surgically managed jones fractures reviewed by the senior author (J.S.T.). Surgical management was complicated by delayed union in three patients, refracture in seven patients, and nonunion in one patient. The 11 procedures were divided between two established techniques: (1) intramedullary screw fixation (N = 6) and (2) inlaid corticocancellous bone graft (N = 5). In the six intramedullary fixation procedures, using other than a 4.5-mm ASIF malleolar screw for internal fixation correlated with failure. In the five inlaid bone graft procedures, undersized corticocancellous grafts and incomplete reaming of the medullary canal correlated with failure. Also, after both procedures, early return to vigorous physical activity is believed to have played a role in delayed union and refracture.

The effect of ambient temperature on the shoe-surface interface release coefficient.

Previous studies of the shoe-surface interface correlated foot fixation with cleat length, configuration, and material composition as well as turf type and surface conditions. Our study examined the effect of temperature on the rotational torsion resistance of artificial turf football shoes. Five football shoe models, a flat-soled basketball-style turf shoe, a natural grass soccer-style shoe, and three multistudded turf shoes, were studied on dry Astro Turf at five temperatures (range, 52 degrees F to 110 degrees F). An assay device, a prosthetic foot mounted on a loaded stainless steel shaft, was used to determine the force necessary to release a shoe from the turf's surface. We used a torque wrench to apply a rotational force so that each shoe was pivoted counterclockwise through an arc of 60 degrees. Our results indicated that release coefficients differ within and among the shoe models at various turf temperatures. We also found that an increase in turf temperature, in combination with cleat characteristics, affects shoe-surface interface friction and potentially places the athlete's knee and ankle at risk of injury. Based on an established risk criterion, which correlated shoe-surface interface combinations in the laboratory with documented clinical occurrences, only the flat-soled basketball-style turf shoe could be designated "safe" or "probably safe" at all five temperatures.

Magnetic resonance imaging of knee disorders. Clinical value and cost-effectiveness in a sports medicine practice.

To prospectively evaluate the clinical value of magnetic resonance imaging of the knee in a referral sports medicine practice, we performed a three-part study. First, we asked 72 consecutive patients a series of clinically relevant questions regarding the ordering of their magnetic resonance imaging scans. Second, we asked the treating physicians at our center if the magnetic resonance imaging findings changed the diagnosis or treatment. Third, we compared the clinical evaluation with the findings on magnetic resonance imaging scans for 37 patients who had arthroscopic confirmation. From the physician's perspective, in only three cases would the results of the scan have changed the diagnosis. Information from the scans was judged to contribute to patient treatment in only 14 of 72 patients. Finally, comparison of clinical evaluation and magnetic resonance imaging findings with findings during arthroscopic procedures showed that clinical evaluation had a sensitivity and specificity of 100% for diagnosis of anterior cruciate ligament injuries, whereas magnetic resonance imaging was 95% sensitive and 88% specific. For isolated meniscal lesions, the clinical assessment had a sensitivity and specificity of 91% compared with 82% and 87%, respectively, for magnetic resonance imaging. For evaluation of articular surface damage, the predictive value of a positive test was 100% for clinical assessment and 33% for the magnetic resonance imaging. We conclude that magnetic resonance imaging is overused in the evaluation of knee disorders and not a cost-effective method for evaluating injuries when compared with a skilled examiner. Clinical assessment equals or surpasses the magnetic resonance imaging in accuracy.

The Nicolas Andry Award. The pathomechanics and pathophysiology of cervical spinal cord injury.

Cervical cord injuries caused during American football games have resulted in reversible, incompletely reversible, and irreversible neurologic deficits. An explanation for this variable response to injury has been obtained from the study of the histochemical responses of a squid axon injury model to mechanical deformation. Data obtained indicate that recovery or lack thereof is directly proportional to the intracellular calcium concentration which in turn is directly proportional to the amount and rate of tension applied to the axon. It is concluded that in most instances of acute spinal injury, disruption of cord function is a result of the effects of local cord anoxia and the increased concentration of intracellular calcium. It is proposed that implementation of therapeutic measures that restore blood flow and reduce cytosolic calcium will increase neurologic recovery.

Cervical spinal stenosis with cord neurapraxia and transient quadriplegia.

Cervical cord neurapraxia is a transient, totally reversible phenomenon that results from compressive deformation of the spinal cord. It occurs as a result of developmental narrowing of the cervical canal, either as isolated entity or in combination with degenerative changes, instability or congenital abnormalities. Uncomplicated stenosis of the cervical canal in an individual with a stable spine does not predispose to permanent neurological injury. Our data does not indicate a correlation between developmental narrowing and permanent neurological sequelae in a spine rendered unstable by football-induced trauma. However, there are data indicating that the occurrence of an episode of cervical cord neurapraxia is not a harbinger, or an indication of susceptibility to permanent neurological sequelae. Nevertheless, we recommended that continued participation in collision activities be restricted in individuals who have a documented episode of cervical cord neurapraxia associated with (i) ligamentous instability; (ii) intervertebral disc disease with cord compression; (iii) significant degenerative changes; (iv) magnetic resonance imaging evidence of cord defect or swelling; (v) symptoms of positive neurological findings lasting more than 36 hours; and (vi) more than one recurrence.

Tibial chondral fissures associated with the lateral meniscus.

This article describes a relatively common lesion of the lateral tibial plateau that has not been reported in the literature. This lesion is a fissure of the articular cartilage parallel to the lateral meniscal rim. Sometimes asymptomatic, this articular fissure was noted in 10 of 61 consecutive patients (16%) undergoing knee arthroscopy in an outpatient surgery unit. This chondral fissure often demarcates an abrupt transition between firm and healthy articular cartilage, which is covered by the lateral meniscus, and exposed articular cartilage, which is soft and fibrillated. Progressive articular degeneration of knees with this lesion has not been documented; therefore, the clinical significance of these chondral fissure is not yet known.

Arthroscopically assisted placement of a supracondylar intramedullary nail: operative technique.

The use of retrograde interlocking intramedullary nails has been described for the treatment of selected supracondylar fractures. A medial parapatellar incision and arthrotomy with its attendant morbidity is generally used for nail placement. Although a closed technique of nail placement has been described, the risks of damaging intra-articular structures with a blind approach have precluded the widespread use of this method. In this article, we present a simple, arthroscopically assisted method for the retrograde intramedullary nailing of supracondylar femoral fractures. This technique affords the potential benefits of intramedullary fixation of these fractures while avoiding the morbidity and complications associated with an arthrotomy. Potential benefits over the standard placement using an arthrotomy include earlier ambulation and soft tissue healing, decreased risk of damage to the knee joint, earlier convalescence with decreased hospitalization time, and better cosmesis.