Considering the cost and complexity of transtibial amputation (TTA) rehabilitation, high-quality literature should inform clinical practice. However, a team of multidisciplinary researchers said that systematic reviews (SRs) suggest this is not the case.
To reach that conclusion, they reviewed the highest-quality evidence available to guide clinical practice for TTA in five prosthetic intervention areas: alignment, feet and ankles, interface, postoperative care, and pylons. Their results were published in Volume 53, Number 2, 2016, of the Journal of Rehabilitation Research & Development.
The following six databases were searched for high-quality SRs and prospective clinical trials that had published between January 1, 1997, and January 1, 2013: PubMed, CINAHL, RECAL Legacy, Cochrane Database of Systematic Reviews, PubMed Central-National Institutes of Health (NIH) Research Publication Database, and Web of Science. Reviewers screened, sorted, rated, and extracted article data. Meta-analyses were conducted when possible. Thirty-one references were included (25 random clinical trials (RCTs) and six SRs), and 23 evidence statements were supported by level 2 evidence and eight by level 1 evidence. Analysis revealed that all RCTs reported randomization and reasonable data presentation; concealed allocation and blinding were not widely used; mean attrition was 11 percent; SRs included no meta-analyses; functional level was poorly reported; grouping feet and ankle components by functional classification enabled meta-analyses, though variance was considerable given the small sample sizes; in 31 total articles, 32 funding disclosures were made; and the most represented sponsor was the U.S. Department of Veterans Affairs, with 30 percent of the government sponsorships and 19 percent of total sponsorships.
The research team concluded that:
- It seems that transverse plane malalignment alters the biomechanics in the joints of both lower limbs. Component malalignment in the sagittal and coronal planes are detectable by the patient at an established magnitude.
- Regarding prosthetic feet and ankle systems, the single axis foot offers an advantage in terms of sagittal kinematics compared with multiaxial (MA) and energy storing and release (ESAR) feet. Adding MA function to a foot, however, seems to improve involved-side kinetics. Use of ESAR feet seems to improve bioenergetics and prosthetic-side kinetics on both flat ground and stairs compared with SACH, flexible keel, and MA feet; however, greater benefit in many of these areas may be experienced with the further addition of a vertical shock pylon function to an ESAR foot.
- Regarding interfaces, use of gel liners compared with specific weight bearing sockets improves load distribution, comfort, ambulatory independence, and suspension. Use of a vacuum-assisted suspension system relative to a total surface bearing system reduces pistoning and time for prosthetic fitting but may come with reduced step activity. Of the topics studied, the interface topic had the highest attrition and bias risk, identifying this as an area to which greater research focus may be needed.
- Post-operatively, the use of rigid removable dressings (RRDs) and semi-RRDs reduce post-amputation edema more effectively than elastic compression alone, and the use of RRDs offers further improvements in terms of wound infection rates, healing times, and time to prosthetic fitting.
- Use of teletorsion pylons and torsion adapters results in comparable spatiotemporal and biomechanical gait parameters in overground walking, stepping down, and turning maneuvers relative to rigid pylons.
Prosthetic interventions are generally safe for patients with TTAs. High-quality literature enabled formulation of evidence statements to support select clinical practice areas, though quantity was lacking. Thus, numerous topics related to TTA care lack rigorous evidence, according to the researchers. Although blinding in prosthetic research requires increased funding and effort, it could greatly improve the methodologic quality of prosthetic research.
