The goal of our study was to estimate the effect of receiving inpatient rehabilitation on SRUs compared with generalized consultation rehabilitation on general medical/surgical units. We found that for veterans after LE amputation, there were incremental benefits of receiving specialized compared with generalized during the acute postoperative period. Veterans receiving specialized rehabilitation were more likely to be discharged home from the hospital and to receive a prescription for a prosthetic limb within 1 year post amputation. Most noticeably, these patients had a 33% greater improvement in physical functioning at rehabilitation discharge. It is noteworthy that only 20.5% of patients who received inpatient rehabilitation during the acute postoperative period received rehabilitation on a SRU, and only 28% of the amputees in this sample had evidence of inpatient rehabilitation during that time period.
If we consider 2 patients with different clinical characteristics, the patient more likely to be discharged home based on these clinical variables is also less likely selected for specialized rehabilitation. The fact that selection bias seems to be operating in favor of generalized suggests that rehabilitation professionals are preferentially selecting those amputees for more intensive services with circumstances that complicate discharge planning. Factors that confound home discharge need to be recognized by rehabilitation professionals and policy makers alike as being legitimate determinants of rehabilitation need on par with traditional concepts of medical necessity.
Persons with dysvascular amputations rarely receive a prosthetic limb during inpatient rehabilitation because the residual limb is not fully healed.31
It may be that specialized rehabilitation better prepares amputees for the training and use of a prosthesis in the follow-up period. The relationship between type of rehabilitation and receipt of a prosthetic limb needs to be studied further.
Similar to our findings of improvement in physical functioning, Turney et al found that the majority (63%) of lower limb amputees who were appropriately referred to intensive inpatient rehabilitation were able to ambulate independently after rehabilitation.32
There is a great deal of interaction among patients and staff on SRUs because treatment occurs in a designated area. Patients may benefit from reinforcement and encouragement as they watch other patients improve their functional status. This interaction, along with more opportunity to focus on functional goals and more aggressive therapy, is part of the intentional process of specialized rehabilitation, which applies treatments in a supportive and hopefully empowering setting. These differences may account for some of the incremental improvements in physical functioning.
In our previous work, we found that patients who received inpatient rehabilitation during the acute postoperative period were 1.5 times more likely to survive compared with patients with no inpatient rehabilitation.2
In this study, we found that once inpatient rehabilitation is made available, there is no strong evidence of incremental benefit of receiving specialized over generalized rehabilitation in terms of survival. The greatest incremental benefit of specialized over generalized inpatient rehabilitation seems in improving quality of life (functional status, receipt of a prosthetic limb, and the chance of home discharge). Rehabilitation clinicians on a SRU may have opportunity to focus on achieving optimal rather than the minimally necessary outcomes. With the known short life spans among this population,11
focus on quality of life outcomes seems vital.
This study had several limitations. Our p score analysis properly controlled for selection bias due to measured patient- and facility-level characteristics, but could not control for selection bias due to unmeasured characteristics. We attempted to measure all relevant characteristics, but further research is needed on additional clinical differences that might not have been available to us in the data. Certain findings in this VHA amputee population may not generalize to patients in the private sector. The majority of veterans are males, and it is unknown if findings can be applied to females. Race and ethnicity were not included because of the large amount of missing or unknown information. Moreover, although the acute postoperative inpatient rehabilitation care pattern used in this study was the most common among veteran amputees, it comprises less than half the veterans who received inpatient rehabilitation. Future studies will need to be directed towards studying the outcome implications of different rehabilitation care patterns, for example, inpatient rehabilitation after discharge from the index surgical stay or as outpatients.
Our observational study provides evidence that rehabilitation on an SRU during the acute postoperative period has incremental benefits after LE amputation compared with receiving rehabilitation on general medical/surgical units. Confidence in our findings is bolstered by the results of our sensitivity analysis, which showed that that our findings would remain the same even if there was an unmeasured characteristic that had a moderately strong effect on both receiving specialized rehabilitation and the outcome. We acknowledge that the results of observational studies must be interpreted cautiously and that only randomized controlled trials (RCT) can definitively determine causal relationships. However, as noted during a December 2007 Institute of Medicine meeting, RCTs are not always optimal or possible because of timing, cost, etc.33
That meeting called for “comparative effectiveness research” defined as a process “comparing biologically focused interventions controlling for patient and system attributes.”34
The p score risk-adjustment methods applied in this study meet this definition. RCTs cannot be undertaken for all interventions in which benefit is unknown, particularly when strong beliefs about the advantages of services make randomization ethically difficult.
To our knowledge, our study was the first study that examined outcomes of different types of rehabilitation after LE amputation. Care of persons after LE amputation is gaining more attention due to the increased media attention of soldiers returning from the conflicts in Afghanistan and Iraq. In July 2007, CARF published new accreditation standards for amputation specialty programs effective January 2008.35
These new standards reflect consensus among rehabilitation professionals that persons with new amputations benefit from intensive, organized interdisciplinary rehabilitation services. Future outcome studies are needed not only to identify those patients who will benefit most from rehabilitation interventions but also to determine which levels of rehabilitation are cost-effective with respect to the outcomes attained.