Kim D. Anderson

Outcome measures in spinal cord injury: Recent assessments and recommendations for future directions

Study design:Review by the spinal cord outcomes partnership endeavor (SCOPE), which is a broad-based international consortium of scientists and clinical researchers representing academic institutions, industry, government agencies, not-for-profit organizations and foundations.Objectives:Assessment of current and evolving tools for evaluating human spinal cord injury (SCI) outcomes for both clinical diagnosis and clinical research studies.Methods:a framework for the appraisal of evidence of metric properties was used to examine outcome tools or tests for accuracy, sensitivity, reliability and validity for human SCI.Results:Imaging, neurological, functional, autonomic, sexual health, bladder/bowel, pain and psychosocial tools were evaluated. Several specific tools for human SCI studies have or are being developed to allow the more accurate determination for a clinically meaningful benefit (improvement in functional outcome or quality of life) being achieved as a result of a therapeutic intervention.Conclusion:Significant progress has been made, but further validation studies are required to identify the most appropriate tools for specific targets in a human SCI study or clinical trial.

Functional Recovery Measures for Spinal Cord Injury: An Evidence-Based Review for Clinical Practice and Research

Abstract Background/Objective: The end goal of clinical care and clinical research involving spinal cord injury (SCI) is to improve the overall ability of persons living with SCI to function on a daily basis. Neurologic recovery does not always translate into functional recovery. Thus, sensitive outcome measures designed to assess functional status relevant to SCI are important to develop. Method: Evaluation of currently available SCI functional outcome measures by a multinational work group. Results: The 4 measures that fit the prespecified inclusion criteria were the Modified Barthel Index (MBI), the Functional Independence Measure (FIM), the Quadriplegia Index of Function (QIF), and the Spinal Cord Independence Measure (SCIM). The MBI and the QIF were found to have minimal evidence for validity, whereas the FIM and the SCIM were found to be reliable and valid. The MBI has little clinical utility for use in the SCI population. Likewise, the FIM applies mainly when measuring burden of care, which is not necessarily a reflection of functional recovery. The QIF is useful for measuring functional recovery but only in a subpopulation of people with SCI, and substantial validity data are still required. The SCIM is the only functional recovery outcome measure designed specifically for SCI. Conclusions: The multinational work group recommends that the latest version of the SCIM (SCIM III) continue to be refined and validated and subsequently implemented worldwide as the primary functional recovery outcome measure for SCI. The QIF may continue to be developed and validated for use as a supplemental tool for the nonambulatory tetraplegic population.

The impact of spinal cord injury on sexual function: concerns of the general population.

Study Design:Secure, web-based survey.Objectives:Obtain information from the spinal cord injured (SCI) population regarding sexual dysfunctions, with the aim of developing new basic science and clinical research and eventual therapies targeting these issues.Setting:Worldwide web.Methods:Individuals 18 years or older living with SCI. Participants obtained a pass-code to enter a secure website and answered survey questions. A total of 286 subjects completed the survey.Results:The majority of participants stated that their SCI altered their sexual sense of self and that improving their sexual function would improve their quality of life (QoL). The primary reason for pursuing sexual activity was for intimacy need, not fertility. Bladder and bowel concerns during sexual activity were not strong enough to deter the majority of the population from engaging in sexual activity. However, in the subset of individuals concerned about bladder and/or bowel incontinence during sexual activity, this was a highly significant issue. In addition, the occurrence of autonomic dysreflexia (AD) during typical bladder or bowel care was a significant variable predicting the occurrence and distress of AD during sexual activity.Conclusion:Sexual function and its resultant impact on QoL is a major issue to an overwhelming majority of people living with SCI. This certainly constitutes the need for expanding research in multiple aspects to develop future therapeutic interventions for sexual health and SCI.Sponsorship:Christopher Reeve Foundation (#36708, KDA); Reeve-Irvine Research Center.

Quantitative assessment of forelimb motor function after cervical spinal cord injury in rats: relationship to the corticospinal tract.

Approximately 50% of human spinal cord injuries (SCI) are at the cervical level, resulting in impairments in motor function of the upper extremity. Even modest recovery of upper extremity function could have an enormous impact on quality of life for quadriplegics. Thus, there is a critical need to develop experimental models for cervical SCI and techniques to assess deficits and recovery of forelimb motor function. Here, we analyze forelimb and forepaw motor function in rats after a lateral hemisection at C5 and assessed the relationship between the functional impairments and the extent of damage to one descending motor system, the corticospinal tract (CST). Female Sprague-Dawley rats were trained on various behavioral tasks that require the forelimb, including a task that measures gripping ability by the hand (as measured by a grip strength meter, GSM), a food reaching task, and horizontal rope walking. After 8 weeks of post-injury testing, the distribution of the CST was evaluated by injecting BDA into the sensorimotor cortex either ipsi- or contralateral to the cervical lesion. Complete unilateral hemisection injuries eliminated the ability to grip and caused severe impairments in food retrieval by the forepaw ipsilateral to the lesion. There was no indication of recovery in either task. In cases in which hemisections spared white matter near the midline, there was some recovery of forelimb motor function over time. Assessment of rope climbing ability revealed permanent impairments in forelimb use and deficits in hindlimb use and trunk stability. Sensory testing using a dynamic plantar aesthesiometer revealed that there was no increase in touch sensitivity in the affected forelimb. For the cases in which both histological and behavioral data were available, spared forelimb motor function was greatest in rats in which there was sparing of the dorsal CST.

The dorsolateral corticospinal tract in mice: An alternative route for corticospinal input to caudal segments following dorsal column lesions

In rodents, the main contingent of corticospinal tract (CST) axons descends in the ventral part of the dorsal column. There is, however, a contingent of CST axons that descends in the dorsolateral column (the “dorsolateral corticospinal tract,” or DLCST). Here, we define some of the features of the DLCST by tracing CST projections following injections of biotinylated dextran amine into the sensorimotor cortex, assessing the distribution of DLCST axons and terminal arborizations in intact mice and in mice in which the main contingent of CST axons in the dorsal column had been transected. Axons of the DLCST diverge from the main tract at the pyramidal decussation, gather in fascicles in the dorsolateral gray matter below the spinomedullary junction, and project in a gradual trajectory laterally toward the dorsolateral column over the first few cervical segments. DLCST axons then project along the dorsolateral column to sacral levels, giving rise to collaterals that project into the gray matter. Labeled DLCST axons were most abundant in cervical segments, where they were often collected in fascicles, and progressively decreased in number in more caudal segments. Tracing of DLCST axons in mice with selective lesions of the dorsal column revealed that DLCST axons arborize extensively throughout the dorsal and ventral horns and that the overall territory that the DLCST axons invade is similar to the territory innervated by the CST axons in the main tract. Some DLCST axon arbors with varicosities are seen near large neurons in the ventral horn (presumed motoneurons). Substantial numbers of DLCST axons project across the midline to the gray matter on the contralateral side. Thus, the DLCST provides an alternate route for CST input to caudal segments, which is of particular relevance for studies of CST distribution and function following partial spinal cord injuries. J. Comp. Neurol. 472:463–477, 2004.

United States (US) multi-center study to assess the validity and reliability of the Spinal Cord Independence Measure (SCIM III)

Study design:Multi-center, prospective, cohort study.Objectives:To assess the validity and reliability of the Spinal Cord Independence Measure (SCIM III) in measuring functional ability in persons with spinal cord injury (SCI).Setting:Inpatient rehabilitation hospitals in the United States (US).Methods:Functional ability was measured with the SCIM III during the first week of admittance into inpatient acute rehabilitation and within one week of discharge from the same rehabilitation program. Motor and sensory neurologic impairment was measured with the American Spinal Injury Association Impairment Scale. The Functional Independence Measure (FIM), the default functional measure currently used in most US hospitals, was used as a comparison standard for the SCIM III. Statistical analyses were used to test the validity and reliability of the SCIM III.Results:Total agreement between raters was above 70% on most SCIM III tasks and all κ-coefficients were statistically significant (P<0.001). The coefficients of Pearson correlation between the paired raters were above 0.81 and intraclass correlation coefficients were above 0.81. Cronbach’s-α was above 0.7, with the exception of the respiration task. The coefficient of Pearson correlation between the FIM and SCIM III was 0.8 (P<0.001). For the respiration and sphincter management subscale, the SCIM III was more responsive to change, than the FIM (P<0.0001).Conclusion:Overall, the SCIM III is a reliable and valid measure of functional change in SCI. However, improved scoring instructions and a few modifications to the scoring categories may reduce variability between raters and enhance clinical utility.

Quantitative assessment of deficits and recovery of forelimb motor function after cervical spinal cord injury in mice

A large proportion of spinal cord injuries (SCIs) in humans are at the cervical (C) level, but there are few tests to quantitatively assess forelimb motor function after cervical spinal cord injury in rodents. Here, we describe a simple and reliable technique for assessing forelimb grip strength over time. Female C57Bl/6 mice were trained on the Grip Strength Meter (GSM, TSE-Systems), then received a lateral hemisection of the spinal cord at level C5, C6, C7, or T1. Gripping ability by each forepaw was then tested for 4 weeks postinjury. Before injury, there was no significant difference in the force exerted by either forepaw. After hemisections at C5, C6, or C7, the forepaw ipsilateral to the injury was initially completely unable to grip (day 2 postinjury), and there was a slight transient decrease in the strength of the contralateral paw compared to presurgical levels. The ipsilateral forepaw exhibited no ability to grip until about 10-14 days postlesion, at which time grip reappeared and strength then recovered over a period of a few days to a level that was about 50% of preinjury levels. Grip strength was minimally and transiently affected by hemisection at T1. The grip strength analysis provides a convenient, quantitative measure of the loss and recovery of forelimb function after cervical injury.

Bilateral cervical contusion spinal cord injury in rats

There is increasing motivation to develop clinically relevant experimental models for cervical SCI in rodents and techniques to assess deficits in forelimb function. Here we describe a bilateral cervical contusion model in rats. Female Sprague-Dawley rats received mild or moderate cervical contusion injuries (using the Infinite Horizons device) at C5, C6, or C7/8. Forelimb motor function was assessed using a grip strength meter (GSM); sensory function was assessed by the von Frey hair test; the integrity of the corticospinal tract (CST) was assessed by biotinylated dextran amine (BDA) tract tracing. Mild contusions caused primarily dorsal column (DC) and gray matter (GM) damage while moderate contusions produced additional damage to lateral and ventral tissue. Forelimb and hindlimb function was severely impaired immediately post-injury, but all rats regained the ability to use their hindlimbs for locomotion. Gripping ability was abolished immediately after injury but recovered partially, depending upon the spinal level and severity of the injury. Rats exhibited a loss of sensation in both fore- and hindlimbs that partially recovered, and did not exhibit allodynia. Tract tracing revealed that the main contingent of CST axons in the DC was completely interrupted in all but one animal whereas the dorsolateral CST (dlCST) was partially spared, and dlCST axons gave rise to axons that arborized in the GM caudal to the injury. Our data demonstrate that rats can survive significant bilateral cervical contusion injuries at or below C5 and that forepaw gripping function recovers after mild injuries even when the main component of CST axons in the dorsal column is completely interrupted.

Spinal cord injury influences psychogenic as well as physical components of female sexual ability

Study design:Secure, web-based survey.Objectives:Elicit specific information about sexual function from women with spinal cord injuries (SCI).Setting:World-wide web.Methods:Individuals 18 years or older living with SCI obtained a pass code to enter a secure website and then answered survey questions.Results:Bladder and/or bowel incontinence during sexual activity and/or sexual intercourse were significant concerns and prevented some women from seeking sexual activity. Autonomic dysreflexia (AD) during sexual activity was interpreted negatively by many and was found to interfere with sexual activity. Most subjects reported difficulty becoming psychologically aroused as well as physically aroused, which were both correlated with feeling that their SCI had altered their sexual sense of self. An inverse relationship existed between developing new areas of arousal above the level of lesion and not having sensation or movement below the lesion. The most commonly reported sexual stimulation leading to the best arousal involved stimulation of the head/neck and torso areas. The majority of subjects reported having experienced intercourse postinjury. Most participants reported difficulty with positioning during foreplay and intercourse, vaginal lubrication, and spasticity during intercourse. Almost half reported experiencing orgasm postinjury and this was positively associated with the presence of genital sensation.Conclusion:SCI significantly impairs psychological and physical aspects of female sexual arousal. In addition, bladder and bowel incontinence as well as AD negatively impact sexual activity and intercourse.Sponsorship:Christopher Reeve Foundation (#36708, KDA); Reeve-Irvine Research Center.

Acceptable benefits and risks associated with surgically improving arm function in individuals living with cervical spinal cord injury.

Study Design:Secure, web-based survey.Objectives:To determine how quadriplegics in the US view tendon transfer surgeries (TTS) and what activities of daily living (ADL) involving arm/hand function are important in improving quality of life (QoL).Setting:World wide web.Methods:Individuals ⩾18 years of age living with a cervical spinal cord injury (SCI). Participants obtained a pass code to enter a secure website and answered survey questions. A total of 137 participants completed the survey.Results:Two-thirds of participants had injury levels between C4/5 and C5/6. Over 90% felt that improving their arm/hand function would improve their QoL. ADL that were ranked most important to regain were dressing, feeding, transferring in/out of bed, and handwriting. Less than half of the participants had never been told about TTS and only 9% had ever had TTS. Nearly 80% reported that they would be willing to spend 2–3 months being less independent, while recovering from surgery, to ultimately become more independent. Over 75% reported that the ideal time preferred to have TTS, if chosen, would be within 5 years post-injury.Conclusion:Regaining arm and hand function is of primary importance to individuals with cervical SCI, in particular, to increase independence in multiple ADL. There is a critical need in the US to improve awareness of TTS as a viable option for improving arm/hand function in some people. This information needs to be provided early after injury so that informed choices can be made within the first 5 years.Sponsorship:Funded by the National Center for Muscle Rehabilitation Research (UCSD-39889) and the Reeve-Irvine Research Center.