Activator Methods Chiropractic Technique (AMCT) has based its methods on a systematic protocol developed to determine the functional short leg or the “pelvic deficient side” Relative changes in leg length must be observed accurately by the examiner in order to be certain that the diagnosis and correction of subluxation were effective. Research has been conducted in the past to evaluate interexaminer reliability of prone leg-length assessment, with findings that reliability can be fair to good. Motion palpation and misalignment palpation have been determined to have poor to moderate reproducibility. However, these remain the gold standard of analysis at chiropractic colleges. The objective of this study was to determine if the AMCT procedures for determining leg-length discrepancy could be taught effectively by observing for reproducibility between examiners in a student population.
In a chiropractic college technique classroom setting, prior to training in AMCT procedures, 80 student patients were instructed to lie in the prone extended position. Each was instructed to wear shoes with welts or surgical boots and to remain motionless throughout all evaluative procedures. A chiropractor rated at advanced proficiency in AMCT used leg-length analysis to evaluate each student patient for leg- length discrepancy. The procedure includes observation of the shoe welt in the prone extended position; cupping the lateral malleoli with the examiner’s palms; and a “6-point landing” which involves positioning the index and middle fingers of the examiner around the lateral malleoli and the thumbs on the patient’s heels. Each student patient was assessed to have a right short leg, a left short leg, or even leg lengths. The results were recorded by the examiner and concealed. Immediately following, 80 untrained student doctors evaluated each of the student patients based on their prior knowledge of leg-length analysis. Results for each were recorded on a ballot and concealed from the next student doctor in an envelope as they rotated to the next student patient until all 80 were evaluated. The envelopes and ballots were collected and the student doctors’ results were compared to the AMCT doctor. Approaching the end of the Basic AMCT course, the procedure above was repeated by both the AMCT doctor and the trained student doctors. The data were analyzed and interexaminer reliability was calculated based on the student doctors’ results compared to the AMCT doctor’s results pre- and post- training
Pre-training analysis revealed an average of 69.9% between the students and the AMCT examiner in the 80 subjects, whereas post-training analysis revealed an average of 82.2% agreement. Overall improvement was found in 67% of the cases upon post-training analysis. Results were consistent in both pre- and post-training analysis in 14% of the cases and agreement declined in 19% of cases. Forty-three percent of students were in 100% agreement with the AMCT examiner after course training, compared to only 14% prior to course training. Sixty-six percent were at or above 80% agreement post-training, compared to 45% pre-training; 78% were at or above 70% agreement post-training, compared to 57% pre training; and only 10% were below 50% agreement after being trained in AMCT leg-length analysis, compared to 24% prior to being trained in AMCT leg checks.
The data collected indicate that leg-length analysis utilizing the AMCT protocol can be effectively taught in order to generate reproducible results. When a standard procedure is utilized, the results of interexaminer reliability remain most consistent. Therefore if leg-length analysis is going to be used in practice, it should be recommended that AMCT leg checks be taught in chiropractic colleges to improve reliability in the field. Although leg-length evaluation is used only for functional deficiencies, there was no exclusion of student patients who have a structural short leg, as every student is a class participant. This inclusion may have skewed results. Students or doctors in training of leg-length analysis must be made aware of the need to evaluate for a structural short leg using Allis’ test, tape measure, or X-ray analysis of femur head heights during their initial examination. They should also know that patient history of childhood epiphyseal disease or fracture could indicate an existing structural problem. The reproducibility of AMCT is dependent on some variables, and in this particular study footwear was controlled. However, inappropriate tables and patient positioning could have resulted in lower reliability. It is standard with AMCT to utilize a hi-lo elevation table to eliminate active positioning; therefore, weight bearing distortions and postural asymmetries are preserved. This study does not address the validity or clinical significance of prone leg checks. Many field practitioners value leg-length assessment to determine pelvic obliquity, assuming abnormal loading results and affects spinal alignment.
Pre-training analysis revealed an average of 69.6% agreement between the students and the AMCT examiner in the 80 subjects, whereas post-training analysis revealed an average of 82.2% agreement. Overall improvement was found in 67% of the cases upon post-training analysis. Results were consistent in both pre- and post-training analysis in 14% of cases and The AMCT leg check protocol appears to offer promise in consistency and interexaminer reliability. The results of this classroom study are encouraging and suggest that with further controlled studies, uniformity in leg-length analysis could be reached within the chiropractic profession.
Author information: Janeen Wallace, DC, New York Chiropractic College