The assessment of work-related activities and limitations in knee disorders

The success of knee treatment programs and surgery must be assessed, in part, by both the ability to return patients to work and the documentation of any work-related limitations. Existing occupational rating scales do not rate, in a valid manner, the effect of altered knee function on work activities. We performed a prospective randomized clinical trial in which two different occupational rating systems were tested on 50 patients. One system used job titles and an arbitrary numeric scale for rating occupations; the other used specific criteria for rating job functions according to the intensity, frequency, and duration of certain tasks. The results showed that an effective and valid rating format should consist of five specific objectives: 1) evaluation of different knee functions that typically occur in the work environment; 2) evaluation of work activities separately from sports activities; 3) detection of patients who may have remained at an occupation but who have significantly modified work activities because of knee symptoms; 4) identification of patients who continue to work despite experiencing moderate to severe symptoms; and 5) identification of patients whose work activities decrease because of nonknee-related factors. Furthermore, the results showed that an effective rating system should identify common data reduction errors that can bias the results in analyzing knee-related occupational limitations. The rating system developed circumvents the bias introduced by these anomalies. This system, if adopted by other researchers, would allow for the comparison of treatment results among studies.

Partial tears of the anterior cruciate ligament. Progression to complete ligament deficiency

In a prospective seven-year study, we treated 32 patients with partial ruptures of the anterior cruciate ligament (ACL) verified by arthroscopy. Twelve knees (38%) progressed to complete ACL deficiency with positive pivot shift tests and increased anteroposterior translation on tests with the KT-1000 arthrometer. Patients with partial ACL tears frequently had limitation for strenuous sports, while those developing ACL deficiency had additional functional limitations involving recreational activities. Three factors were statistically significant in predicting which partial tears would develop complete ACL deficiency: the amount of ligament tearing--one-fourth tears infrequently progressed, one-half tears progressed in 50% and three-fourth tears in 86%; a subtle increase in initial anterior translation; and the occurrence of a subsequent re-injury with giving-way.

A rationale for assessing sports activity levels and limitations in knee disorders

Existing published knee rating systems that assess sports participation, knee function, and subjective symptomatology following ligamentous surgical procedures were analyzed. Major errors in questionnaire design and data reduction have led to invalid conclusions. A questionnaire containing a minimum set of rating criteria was formulated to validly assess athletic participation before and after treatment or surgery. Select questions and a data reduction format were established to assess the intensity of sports participation, changes in sports participation, the variables that produced the changes, self-assessed functional limitations, and the ability to participate in different types of sports. A clinical trial of the questionnaire was performed on 59 patients. An interview conducted upon completion of the questionnaire enabled the authors to detect difficulties or inconsistencies in the responses to the questions. The design format described in this report forms the basis for a subjective evaluation of ligamentous surgery. A standard format for analysis of sports participation and knee function is proposed to aid investigators in comparing variations in clinical results.

Functional disability in the anterior cruciate insufficient knee syndrome. Review of knee rating systems and projected risk factors in determining treatment

The complete tear of the anterior cruciate ligament initiates the clinical syndrome represented by continued functional disability. The precise degree of functional disability is highly debated. Agreement is elusive due to the lack of uniform and scientific methodology. An historical review and analysis of functional and subjective rating systems is reported, and the strengths of previous systems are identified. A subjective and functional rating system is proposed in which 6 activity levels are related to pain, swelling, giving-way and overall activity. This is important because of the marked dependence of the functional disability of the anterior cruciate insufficient knee on the activity level of the patient. Thus, activity levels must be rigorously and comprehensively defined. In addition, we propose the utilisation of a risk factor checklist, based on the statistics drawn from our previous articles, to identify those patients at significant risk for future joint arthrosis. Risk factors are grouped under the categories of activity level, symptoms, clinical laxity, meniscal damage, lower limb alignment, tibiofemoral crepitus, patellofemoral factors, rehabilitation and patient compliance. Thirdly, we examine controversial aspects of the anterior cruciate ligament syndrome existing in the literature today and demonstrate why contrasting opinions are not mutually exclusive. Finally we propose our treatment guidelines for management of the acute and chronic anterior cruciate ligament insufficient knee.

Knee sprains and acute knee hemarthrosis: misdiagnosis of anterior cruciate ligament tears

A retrospective study and a prospective study comprising 186 patients with "typical knee sprains" were conducted at the University of Cincinnati Sports Medicine Institute. We concluded that the commonly encountered mild knee sprain may actually be a serious knee injury whose severity is easy to underestimate. Traumatic hemarthrosis indicates a serious knee injury. Arthroscopy showed that a surprising 72 percent of the patients in the prospective study had disruption of the anterior cruciate ligament (partial tear in 28%, complete tear in 44%). In addition of the 72 percent of anterior cruciate ligament tears, associated injuries included meniscus tears (62%), osteochondral fractures or fissures to the joint surface (20%), and other significant ligament disruptions (20%). Any joint effusion within 24 hours of knee injury, no matter how trivial, suggests a need for further diagnostic tests beyond the initial examination. In our study, our clinical examination alone consistently underestimated the extent of injury, resulting in inadequate information for treatment descisions. Conversely, arthroscopy and examination under anesthesia provided information on the extent of injury, allowing an accurate diagnosis and formulation of a rational treatment program.