Biomedical subjects

Hagay Amir

Publications and source records attributed to Hagay Amir.

4 recordsLinked to original sources

PubMed2006

Patellofemoral pain syndrome: validity of clinical and radiological features.

Data regarding validity of clinical and radiographic findings in diagnosing patellofemoral pain syndrome are inconclusive. We prospectively assessed how sensitive and specific key patellofemoral physical examination tests are, and evaluated the prevalence of physical examination and radiographic findings. Sixty-one infantry soldiers with patellofemoral pain syndrome and 25 control subjects were evaluated. The sensitivity of the patellar tilt, active instability, patella alta, and apprehension tests was low (less than 50%); specificity ranged between 72% and 100%. Although the prevalence of positive patellar tilt and active instability tests was significantly greater in subjects with patellofemoral pain syndrome, there were no significant differences between the groups in the results of the other two tests. Soldiers with patellofemoral pain syndrome presented with increased quadriceps angle, lateral and medial retinacular tenderness, patellofemoral crepitation, squinting patella, and reduced mobility of the patella. There were no differences between the groups in the prevalence of lower limb and foot posture alignment and knee effusion. Plain radiography showed increased patellar subluxation in soldiers with patellofemoral pain syndrome. Other radiographic measures (sulcus angle, Laurin angle, Merchant angle, and Insall-Salvati index) were similar in both groups. We provide evidence regarding the validity of clinical and radiographic features commonly used for diagnosing patellofemoral pain syndrome. Physical examinations were more useful than plain radiography.

Adolescent↗

PubMed2004

How safe is primary knee replacement surgery? Perioperative complication rates in Northern Illinois, 1993-1999.

OBJECTIVE: To describe inpatient complications for primary total knee replacement (TKR) in a period of rapidly growing orthopedic surgery capacity, declining length of stay, and more frequent discharge to rehabilitation facilities. METHODS: Complication incidence according to published coding algorithms was estimated for 35,531 primary TKR admissions of northern Illinois residents to 65 Illinois hospitals. Complication odds were estimated as a function of patients' clinical and sociodemographic status, hospital volume, residency training, TKR length of stay, International Classification of Diseases, Ninth Revision (ICD-9) coding intensity, and discharges to skilled nursing or rehabilitation facilities. RESULTS: Primary TKR admissions increased 36% between 1993 and 1999, length of stay declined 43%, average ICD-9 code use increased 31%, and rehabilitation discharges increased 68%. Major complication rates declined 44% (12.4% to 6.9%; P < 0.0001) over this period, reflecting a 50% reduction in the adjusted odds of complication between 1993 and 1999. There was no association of procedure volume and outcome. CONCLUSION: It is likely that the reduction in complications reflects true safety improvements as well as reduced length of stay.

Adolescent↗

PubMed2004

Computerized biofeedback knee goniometer: acceptance and effect on exercise behavior in post-total knee arthroplasty rehabilitation.

OBJECTIVE: To assess device accuracy, patient acceptance, and effect of a computerized biofeedback knee goniometer (CBG), on patients' compliance with active range of motion (AROM) exercises after total knee arthroplasty (TKA). DESIGN: Two-stage study: measurement validation on asymptomatic controls and an unblinded, multiple crossover trial. SETTING: Inpatient rehabilitation. PARTICIPANTS: Asymptomatic controls (n=14) and post-TKA inpatients (n=11). INTERVENTIONS: For measurement validation, CBG-angle measurements were compared with manual, clinician-obtained angles. To assess motivational effect, the CBG was worn after TKA; on alternating days, it either monitored AROM silently (no feedback) or provided audiovisual feedback about reaching preset range of motion (ROM) goals and prompted the patients to exercise when idle. MAIN OUTCOME MEASURES: To assess accuracy, the device's readings were compared with manual measurements. Patient satisfaction was determined by a self-report questionnaire; exercise compliance was assessed by calculating activity rate and stratified interactivity intervals. RESULTS: CBG readings reproduced clinician measurements reliably between 0 degrees and 100 degrees (eta(2)=98.5%). Auditory feedback was more helpful than visual feedback for motivating exercise. During feedback-on days, the mean total activity rate +/- standard deviation was 15.1+/-10.9 activity counts per hour, and the interactivity interval was 6.7+/-5.7 minutes. The activity rate was higher on feedback-off days-22.5+/-11.1 counts/hour (P=.11)-and the mean interactivity interval was 3.6+/-2.7 minutes (P=.07). CONCLUSIONS: The CBG provided reliable, unbiased estimates of clinician measurements of joint angle within the range of 0 degrees to 100 degrees. The CBG was accepted well by most patients. Surprisingly, slightly more ROM activity was noted during feedback-off days than feedback-on days.

Analysis of Variance↗

PubMed2003

Do physicians correctly estimate radiation risks from medical imaging?

Proper use of medical imaging tools requires knowledge of their associated radiation risks, as well as their possible benefits. The authors assessed physicians' knowledge of the radiation risks associated with bone scintigraphy (bone scan) during an annual meeting of the Israeli Orthopedic Society. The mortality risk of radiation-induced carcinoma from bone scan was identified correctly by less than 5% of respondents. The most frequent answer (38.4%) was the option that was least correct. Senior orthopedists estimated lower risks than did residents. Overall, respondents grossly underestimated the potential radiation risk from bone scan.

Bone and Bones↗