30 May 2006

Ossur Scientific E-letter Issue #2 2006

Dear readers,
Welcome to the second issue of the Ossur Scientific E-letter of 2006. In this issue we would like to share some ideas and scientific news.

The Scientific E-letter includes five different scientific papers. The articles cover the subjects of amputation, postoperative treatment, prosthetics/biomechanics, orthotics and quality management. Three of the selected papers have been published in 2006, one 2005 and one 2004.

Amputation

Should Pre-operative Troponin be a Standard Requirement in Patients Undergoing Major Lower Extremity Amputation?
Gibson S.C. Marsh A. Berry C. Payne C. Byrne D.S. Rogers P.N. McKay A.J. Dargie H. Kingsmore D.B.
European Journal of Vascular and Endovascular Surgery. Accepted 18 November 2005. Available online 19 January 2006.

Gibson and colleagues wanted to ascertain the benefits of routinely taking cardiac troponin (cTnI) in patients undergoing lower extremity amputation for critical limb ischemia.

During one year all patients (44) scheduled for lower extremity amputation without unstable coronary disease were recruited to, in addition to routine pre-operative evaluation, also give a blood sample for measurement of serum troponin. The patients were followed up during six weeks after the amputation regarding cardiac events.

It was found that 10 (~22%) of the patients suffered a non-fatal myocardial infarction or died from a cardiac event post-operatively during the follow up time. A raise in pre-operative troponin was associated with two cardiac deaths and one post-operative myocardial infarction. The authors mean that troponin was the only significant predictor of post-operative cardiac events. Further they suggests that routinely pre-operatively measurement of may be of benefits to identify the patients at high risk of cardiac complication, who might benefit from a modified treatment.

Postoperative

Preoperative Clinical Factors Predict Postoperative Functional Outcomes After Major Lower Limb Amputation: An Analysis of 553 Consecutive Patients
Taylor S.M. Kalbaugh C.A. Blackhurst D.W. and et al.
J Vasc Surg 2005;42:227-35

To find the relationship between the preoperative clinical characteristics and postoperative functional outcome after major lower limb amputation Taylor et al performed a retrospective study. They reviewed the files of all patients (553 patients with 627 major amputations) between January 1998 and December 2003 correlating various preoperative factors with postoperative functionality regarding use of prosthesis, survival, maintenance of ambulation and independent living status.

The study group found strong correlation between not wearing a prosthesis postoperatively and not being ambulatory before amputation in decreasing order: above knee amputation, age more than 60, homebound not ambulatory status, dementia, end stage renal disease and coronary artery disease.

Preoperative factors that correlated with postoperative death were in decreasing order: being more than 70 years old, being between 60 and 69 years old and presence of coronal arterial disease.

Preoperative factors that correlated with failure of ambulation were in decreasing order: age over 70 years old, being between 60 and 69 years old, bilateral amputation and end stage of renal disease.

Preoperative factors that independently correlate with failure of maintaining independent living was in decreasing order: more than 70 years old, being between 60 and 69 years old, level of amputation, homebound ambulatory status and presence of dementia.

Present study concluded that persons with limited preoperative ambulatory ability, more than 70 years old, dementia, end stage renal disease and advanced coronal arterial disease have poorer postoperative results. They suggest that those persons with those high risk factors may possible be grouped with bedridden patients. A higher level of amputation affected the possibility to use a prosthesis and living independently negatively. On the other hand the authors found that younger, healthy patients with trans-tibial amputations had postoperative functional outcome similar to what might be expected after a revascularisation of the lower extremity. The authors mean that an amputation in those cases should probably not be considered a failure of therapy, but another option of treatment of extending the patients functionality and independent living.

Prosthetics/biomechanics

Prescription of prosthetic ankle-foot mechanisms after lower limb amputation.
Hofstad C, Van der Linde H, Van Limbeek J, Postema K.
The Cochrane Database of Systematic Reviews 2004, Issue 1. Art. No.: CD003978.pub2. DOI: 10.1002/14651858.CD003978.pub2.

A Cochrane review has been performed to gain information about aspects of prosthetic ankle-foot mechanism and daily functioning of amputees with a prosthesis to achieve appropriate prescription criteria.

The review included 23 studies with 217 participants. The authors found the quality of the studies poor. Only one study was of high quality. All the studies were though using cross-over design allowing sufficient control for confounding.

The review showed that there were benefits of the Flex foot compared to the SACH foot in trans-tibial amputees during decline and inclines walking and increased walking speeds regarding energy cost and gait efficiency.

In the group of high activity trans-femoral amputees, there is limited evidence for the superiority of the Flex foot compared to the SACH foot

The authors mean that there is not enough evidence for the precise prescription criteria for the functional ability related to the prosthetic ankle-foot mechanisms. They suggest that practitioners should consider availability, patient functional needs and cost when prescribing a device.

Orthotics

A systematic review of lateral wedge orthotics-how useful are they in the management of medial compartment osteoarthritis?
Reilly K A. Barker K L. Shamley D.
The Knee. Volume 13, Issue 3, June 2006, Pages 177-183

Reilly et al wanted to gain evidence of the usefulness of lateral wedged foot orthotics. The importance of varus moment in the knee is given in the progression of medial compartment osteoarthritis. Lateral wedges in a shoe have logically been considered to counteract this moment. However the structures and mechanics of the ankle- and subtalar-joint might be disturbed and the wanted effect could be deficient.

The study group performed a comprehensive, systematic review to determine whether evidence exists to support the use of lateral wedges. The included studies assessed the effect of lateral wedges either biomechanically or clinically in a normal or in a patient population. Eleven studies were included.

The authors concluded that reviewed literature did not support the use of lateral wedges. Further they meant that the biomechanics of the foot and ankle during gait has not been taken into consideration in previous research.

Quality management

Advances in Amputee Care
Pasquina P F. Bryant P R. Huang M E. Roberts T L. Nelson V S. Flood K M.
Archives of Physical Medicine and Rehabilitation
Volume 87, Issue 3, Supplement 1 , March 2006, Pages 34-43

The article by Pasquina et al describes the key elements of a successful complete amputee program. The article covers management of, for instance, amputation technique, pain, technical devices and innovations and advancement in the area.

According to the authors the most important key element to success is teamwork. They have to form multidisciplinary teams that should work together with a formulated, integrated and coordinated treatment plan.

Studies have found that teamwork has improved both short- and long- term outcomes. Also activities like vocational rehabilitation, peer support, reintegration in society, sports and recreational activities greatly add to the strength of a treatment program and increase the quality of life of the amputees.

If a program will be successful the members of the team must recognise the importance of the patient's family members have in the entire process and also in the establishment of short and long term goals.

The authors further mean that modern science, advanced technology, and improved material design can be brought together to revolutionize the care for people with amputation. To reach this goal a significant teamwork must be both across and within different disciplines.

Empower Health Care Solutions wish you all the best and is looking forward to provide you interesting scientific news in September 2006!

Best regards,
Louise Klevbo