Rhabdomyolysis and acute renal failure following arthroscopic knee surgery in a college football player taking creatine supplements

We describe a college football player and weight-lifter who unexpectedly developed rhabdomyolysis and nonoliguric acute renal failure (ARF) following arthroscopic knee surgery. There was swelling and pain without evidence of a compartment syndrome postoperatively. The patient reported that he was an avid weight-lifter and that he was taking up to 10 g/d of a creatine supplement during the 6 weeks prior to this surgery. His ARF resolved over several days, with a peak serum creatinine of 2.3 mg/dl and peak creatine kinase (CK) of 194,000 U/l, following administration of intravenous fluids, mannitol, and sodium bicarbonate. Given the rarity of clinically significant rhabdomyolysis with this type of operation, we suggest that the patient's use of creatine increased the risk of skeletal muscle injury due to ischemia from intra-operative tourniquet application.

Dynamic measurements of three-dimensional scapular kinematics: a validation study

The validation of two noninvasive methods for measuring the dynamic three-dimensional kinematics of the human scapula with a magnetic tracking device is presented. One method consists of simply fixing a sensor directly to the acromion and the other consists of mounting a sensor to an adjustable plastic jig that fits over the scapular spine and acromion. The concurrent validity of both methods was assessed separately by comparison with data collected simultaneously from an invasive approach in which pins were drilled directly into the scapula. The differences between bone and skin based measurements represents an estimation of skin motion artifact. The average motion pattern of each surface method was similar to that measured by the invasive technique, especially below 120 degrees of elevation. These results indicate that with careful consideration, both methods may offer reasonably accurate representations of scapular motion that may be used to study shoulder pathologies and help develop computational models.

Comparison of 3-dimensional scapular position and orientation between subjects with and without shoulder impingement

STUDY DESIGN

Nonrandomized 2 group post-test only.

OBJECTIVE

To compare scapular position and orientation between subjects with and without impingement syndrome.

BACKGROUND

Abnormal scapular motion is commonly believed to be a contributing factor to shoulder impingement syndrome.

METHODS AND MEASURES

Twenty nonimpaired subjects with a mean age of 34.3 (+/- 7.5 years) and 17 patients with impingement syndrome with a mean age of 45.8 (+/- 11.0) participated. A 3-dimensional electromechanical digitizer was used to measure scapular position and orientation in 3 planes. Measurements were taken with the arm at the side, elevated in the scapular plane to horizontal, and at maximum elevation. One-way analysis of variance was used to compare nonimpaired subjects to the impingement group and the symptomatic and asymptomatic sides within the impingement group. Five scapular kinematic variables were assessed at each arm position. Orientation was described by posterior tilting angle, upward rotation angle, and internal rotation angle. Position was described by medial-lateral position and superior-inferior position and determined by the distance from the scapula centroid to the seventh cervical vertebra (C7).

RESULTS

During scapular plane elevation of the arm, the scapula showed a general pattern of increasing posterior-tilt angle, increasing upward-rotation angle, and decreasing internal-rotation angle in both impingement and nonimpaired groups. Also, the scapula moved to a more superior position and a slightly more medial position with increasing arm elevation. Compared to nonimpaired subjects (34.6 degrees +/- 9.7), those with impingement demonstrated a significantly lower posterior tilting angle of the scapula in the sagittal plane (25.1 degrees +/- 9.1). Subjects with impingement also demonstrated higher superior-inferior scapular position with maximal arm elevation (5.2 cm +/- 1.6 below the first thoracic vertebrae) compared to nonimpaired subjects (7.5 cm +/- 1.5).

CONCLUSIONS

These results suggest that altered scapular kinematics may be an important aspect of the impingement syndrome.

The three-dimensional passive support characteristics of ankle braces

Studies of the passive support provided by ankle braces have focused primarily on inversion support. The goal of this study was to develop a technique to measure the support provided by ankle braces in all rotational directions and to use this technique to compare four common braces (Ascend, Swede-O, Aircast, and Active Ankle). For this purpose, a 6 degrees-of-freedom linkage was used to measure the flexibility of the ankle complex in 10 healthy subjects. Each subject was tested without brace support and with each of the four braces. Testing was repeated on each subject on two different occasions. The angular displacement at specified moment values and the four segmental flexibility values obtained from the loading portion of the moment-angular displacement data were used in the data analysis. Repeated measure analysis of variance followed by a Student Neuman-Keuls test at p < 0.05 was performed. This statistical analysis was used to identify significant differences among the braces and differences between each brace and the no brace condition. Each of the four braces provided significant support in inversion, eversion, and internal rotation, but the amount of support varied significantly among the braces. In external rotation, only the stirrup braces provided significant support. The braces also varied significantly in the amount of interference with dorsiflexion and plantar flexion. Clinicians may be assisted by objective data on the amount and nature of passive support when prescribing braces to their patients.

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.

Spear tackler's spine. An entity precluding participation in tackle football and collision activities that expose the cervical spine to axial energy inputs

We describe spear tackler's spine, a clinical entity that constitutes an absolute contraindication to participation in tackle football and other collision activities that expose the cervical spine to axial energy inputs. A subset of football players were identified who demonstrated: 1) developmental narrowing (stenosis) of the cervical canal; 2) persistent straightening or reversal of the normal cervical lordotic curve on erect lateral roentgenograms obtained in the neutral position; 3) concomitant preexisting posttraumatic roentgenographic abnormalities of the cervical spine; and 4) documentation of having employed spear tackling techniques. From data obtained by the National Football Head and Neck Injury Registry and the senior author's practice, 15 cases of spear tackler's spine were identified during 1987 to 1990. All 15 cases were evaluated because of complaints referable to the cervical spine or brachial plexus resulting from football injuries. Of these, 11 had complete neurologic recovery without permanent sequelae. Four cases resulted in permanent neurologic deficits: quadriplegia, 2; incomplete hemiplegia, 1; and residual long track signs, 1. Permanent neurologic injury occurred as the result of axial loading of a persistently straightened cervical spine from use of head-impact playing techniques. We suggest that individuals who possess the aforementioned characteristics of spear tackler's spine be precluded from participation in collision activities that expose the cervical spine to axial energy inputs.

The axial load teardrop fracture. A biomechanical, clinical and roentgenographic analysis

The anteroinferior cervical vertebral body corner fracture was originally described by Schneider and Cann as the "teardrop" fracture. This report analyzes the biomechanical, clinical, and roentgenographic features of 55 such fractures obtained from the National Football Head and Neck Injury Registry. Teardrop fractures resulting from tackle football characteristically occurred in players attempting to make a tackle in which initial contact was made with the top or crown of the helmet. There were two fracture patterns associated with the anteroinferior corner (teardrop) fracture fragment: 1) the isolated fracture, which is usually not associated with permanent neurologic sequelae; and 2) the three-part, two-plane fracture in which there is an associated sagittal vertebral body fracture as well as fracture of the posterior neural arch. This latter pattern was almost always associated with permanent neurologic sequelae, specifically quadriplegia. Axial loading of the cervical spine was clearly identified as a mechanism of injury for both fracture patterns. Roentgenographic examination must include both anteroposterior and lateral views with computed tomography or tomography as necessary to determine the presence of the sagittal vertebral body fracture and the integrity of the posterior neural arch.

Axial loading injuries to the middle cervical spine segment. An analysis and classification of twenty-five cases

Injuries to the cervical spine at the C3-C4 level involving the bony elements, intervertebral disks, and ligamentous structures are rare. We present 25 cases of traumatic C3-C4 injuries sustained by young athletes and documented by the National Football Head and Neck Injury Registry. Review of the cases reveals that the response of energy inputs at the C3-C4 level differ from those involving the upper (C1-C2) and lower (C4-C5-C6-C7) cervical segments. Specifically, the C3-C4 lesions appear to be unique with regard to the infrequency of bony fracture, difficulty in effecting and maintaining reduction, and a more favorable recovery following early, aggressive treatment. In the majority of instances, injury at this level results from axial loading of the cervical spine. Lesions were distributed into specific categories: 1) acute intervertebral disc herniation (N = 4), 2) anterior subluxation of C3 on C4 (N = 4), 3) unilateral facet dislocation (N = 6), 4) bilateral facet dislocation (N = 7), and 5) fracture of vertebral body C4 (N = 4). Analysis of these 25 cases suggests that traumatic lesions of the cervical spine in general can be classified as involving the upper (C1-C2), middle (C3-C4), or lower (C4-C7) segments. This is based on our observations from this series that C3-C4 lesions 1) generally do not involve fracture of the bony elements; 2) acute intervertebral disc herniations are frequently associated with transient quadriplegia; 3) reduction of anterior subluxation of C3 on C4 is difficult to maintain; 4) reduction of unilateral facet dislocation is difficult to obtain by skeletal traction and is best managed by closed manipulation and reduction under general anesthesia; and 5) reduction of bilateral facet dislocation is difficult to obtain by skeletal traction and is best managed by open methods. The more favorable results observed in this series of immediate reduction of both unilateral and bilateral facet dislocations deserves emphasis. In two cases of unilateral facet dislocation reduced within 3 hours of injury and subsequently fused anteriorly, significant neurologic recovery occurred. The other four patients, two who underwent an open reduction and laminectomy and two treated closed with skeletal traction, remained quadriplegic. In the four instances of bilateral facet dislocation where reduction was achieved by either closed or open methods, although there was no neurologic recovery, all four patients survived their injuries. However, the three patients who were not successfully reduced died.

Treatment of chronic osteomyelitis complicating nonunion and segmental defects of the tibia with open cancellous bone graft, posterolateral bone graft, and soft-tissue transfer

Forty-two consecutive patients with chronic osteomyelitis complicating persistent tibial nonunion and chronic osteomyelitis complicating tibial fracture with segmental bone loss were treated from January 1979 through December 1986 using a protocol including either open cancellous bone grafting (Friedlaender-Papineau technique), posterolateral bone grafting (Harmon technique), or local or microvascular soft-tissue transfer before cancellous bone grafting. Each patient had undergone surgical debridement and intravenous antibiotic therapy before inclusion in this study. Patients were classified using a staging system which included consideration of anatomic location of the infection within the bone; extent of bone involvement; quality of soft-tissue envelope and vascular integrity; and generalized host status. The overall success rate for arresting the osteomyelitis and healing the nonunion was 62% (26/42). If the six patients who refused additional bone graft surgery, the one patient who represented poor patient selection, and the patient who refused ankle arthrodesis are eliminated, the success rate for healing of the nonunion and resolving the osteomyelitis in this difficult patient population is: open bone cell graft, 66% (12/18); soft-tissue transfer 87.5%, (7/8); and posterolateral bone grafting, 87.5% (7/8). Use of a standardized classification system allows comparison of treatment results. Adequate debridement is crucial in treating osteomyelitis complicating established long bone fractures and nonunions. Determining the extent of debridement has proven to be the single most difficult aspect technically. Patient selection and pretreatment education are crucial. Caring for these patients is not only labor intensive and demanding of personnel and hospital resources, but demanding of the patients as well.

The epidemiologic, pathologic, biomechanical, and cinematographic analysis of football-induced cervical spine trauma

Epidemiologic, pathologic, biomechanical, and cinematographic data on head and neck injuries occurring in tackle football have been compiled since 1971 by the National Football Head and Neck Injury Registry. Preliminary analysis performed in 1975 indicated that the majority of serious cervical spine football injuries were caused by axial loading. Based on this observation, the National Collegiate Athletic Association (NCAA) and National Federation of High School Athletic Associations (NFHSAA) implemented rule changes banning "spearing" and the use of the top of the helmet as the initial point of contact in striking an opponent during a tackle or block. Between 1976 and 1987, as a result of these rule changes, the Registry has documented a dramatic decrease in both the total number of cervical spine injuries and those resulting in quadriplegia at both the high school and college level. It is suggested that development and implementation of similar preventative measures based on clearly defined injury mechanisms would decrease injury rates in diving, rugby, ice hockey, trampolining, wrestling, and other high-risk sports as well.

Spinal injury at the level of the third and fourth cervical vertebrae resulting from the axial loading mechanism: an analysis and classification

The traumatic C3-C4 level injuries sustained by young athletes and documented by the National Football Head and Neck Injury Registry are discussed. Twenty-eight of 885 (2.8 per cent) injuries involved the C3-C4 vertebrae. Review of these cases reveals that the response to energy inputs at the C3-C4 level differ from that of those involving the upper (C1-C2) and lower (C5-C6) cervical segments. Specifically, these lesions appear unique with regard to infrequency of bony fracture, difficulty in effecting and maintaining reduction, and their more favorable response to early aggressive treatment. It is the authors' belief that these lesions resulting from athletic activity are due to axial loading.

The National Football Head and Neck Injury Registry: 14-year report on cervical quadriplegia (1971-1984)

The specter of catastrophic cervical neurotrauma resulting from athletic participation, although infrequent, has been consistently associated with football, water sports, gymnastics, rugby, and ice hockey. Injury involving intracranial hemorrhage can result in death or permanent neurologic impairment, whereas certain fractures and dislocations of the cervical spine are associated with quadriplegia. Athletic injuries to both the central nervous system and spinal cord demand our attention as an active area of clinical and basic injury. A review of the available literature reveals changing injury patterns as well as current concepts regarding the mechanism responsible for most athletic injuries to these structures. Accurate descriptions of the mechanism(s) responsible for a particular injury transcend simple academic interest. In order that preventive measures be implemented, the manner in which injury occurs must be accurately defined. The purpose of this article is to describe how the application of this principle resulted in the significant reduction of cervical spine injuries associated with quadriplegia that have occurred in tackle football since 1976.

Neurapraxia of the cervical spinal cord with transient quadriplegia

The purpose of this study was to define as a distinct clinical entity the syndrome of neurapraxia of the cervical spinal cord with transient quadriplegia. The sensory changes include burning pain, numbness, tingling, and loss of sensation, while the motor changes range from weakness to complete paralysis. The episodes are transient and complete recovery usually occurs in ten to fifteen minutes, although in some patients gradual resolution occurs over a period of thirty-six to forty-eight hours. Except for burning paresthesia, pain in the neck is not present at the time of injury and there is complete return of motor function and full, pain-free motion of the cervical spine. In our series, routine roentgenograms of the cervical spine were negative for fractures or dislocations in all patients. However, the roentgenographic findings did include developmental spinal stenosis in seventeen patients, congenital fusion in five patients, cervical instability in four patients, and intervertebral disc disease in six patients. Spinal stenosis was determined by two different roentgenographic methods. The first was the standard method, and the second was a ratio method devised by us. Both measurements were made at the level of the third through the sixth vertebral body on a routine lateral roentgenogram of the cervical spine that was available for twenty-four of the thirty-two patients and for a control group of forty-nine male subjects of similar age who did not have any neurological complaints. Using the ratio method, a measurement of less than 0.80 indicated significant spinal stenosis in the group of twenty-four patients for whom roentgenograms were available, as compared with a ratio of approximately 1.00 or more in the control group. There was statistically significant spinal stenosis (p less than 0.0001) in all of the patients as compared with the control subjects by both methods of determining spinal stenosis. A survey of 503 schools participating in National Collegiate Athletic Association (NCAA) football in the 1984 season found that 1.3 per 10,000 athletes had a history that was suggestive of neurapraxia of the cervical spinal cord. The phenomenon of neurapraxia of the cervical spinal cord occurs in individuals with developmental stenosis of the cervical spine, congenital fusion, cervical instability, or protrusion of an intervertebral disc in association with a decrease in the anteroposterior diameter of the spinal canal. We postulate that in athletes with diminution of the anteroposterior diameter of the spinal canal the spinal cord can, on forced hyperextension or hyperflexion, be compressed, causing transitory motor and sensory manifestations.(ABSTRACT TRUNCATED AT 400 WORDS)

The National Football Head and Neck Injury Registry. 14-year report on cervical quadriplegia, 1971 through 1984

Data on cervical spine injuries resulting from participation in football have been compiled by a national registry. Analysis of epidemiologic data and cinematographic documentation clearly demonstrated that the majority of cervical fractures and dislocations were due to axial loading. On the basis of this observation, rule changes banning both deliberate "spearing" and the use of the top of the helmet as the initial point of contact in making a tackle were implemented at the high school and college level. Subsequently, a marked decrease in cervical spine injury rates has occurred. The occurrence of permanent cervical quadriplegia decreased from 34 in 1976 to five in the 1984 season. It is suggested that axial loading of the cervical spine is also responsible for the catastrophic injuries in diving, rugby, ice hockey, and gymnastics. Implementation of appropriate changes in playing techniques and/or equipment modifications could possibly reduce the incidence of cervical spine injuries in these activities.