The Prevalence and Impact of Pain Associated With Upper-limb Amputation
The prevalence of MSCs among those with limb absence was twice that observed in the general population, reported at 57 percent over the last four weeks and at 65 percent for at least four consecutive weeks during the past year.
In 2011, The O&P EDGE published an article, "Losses Beyond the Limb" (December 2011), that addressed some of the challenges observed after an upper-limb amputation that, while not immediately related to the amputation event, had a collective impact on the health and well-being of the individual. Chief among these considerations was pain in its various forms, including phantom limb pain, limb pain persisting beyond the acute healing of the amputation site, and pain associated with overuse of the remaining limb. Recent years have seen an expansion of the literature in this area, inviting further consideration of the prevalence and impact of pain among individuals with congenital upper-limb deficiencies and acquired upper-limb amputations. This article reviews the key findings of these publications and better defines the overall phenomena in these populations.
In a study by Dutch researchers, complaints of the arms, neck, and/ or shoulders not immediately caused by acute trauma or by any systemic disease were deemed to constitute musculoskeletal complaints (MSCs) that develop as a result of repetitive movements, awkward postures, and forces.1 Seeking to determine if such MSCs would be equally observed in both those with acquired amputations as well as congenital limb deficiencies, how these prevalence rates would compare to those observed in the general public, and whether such MSCs are negatively associated with overall self-reported health, researchers sent out postal surveys to a convenience sample of adults with unilateral upper-limb absence at or proximal to the carpal level. The surveys were centered on the question, "Did you have regular complaints of the muscles, tendons, and/or bones during the last four weeks, which were not caused by an accident, sports injury, infection, or joint disease?" The survey also included a similar question regarding any such complaints that persisted for at least four consecutive weeks at any time during the prior year. The nature of any pain and its associated disability were subsequently reported.
Of the 627 solicited surveys, 263 usable surveys were returned from 110 individuals with congenital deficiencies and 153 individuals with acquired upper-limb amputations. A convenience sample of 108 age- and gender-matched healthy controls was also surveyed.
The control sample provided a reminder that, while MSCs are common among individuals with upper-limb deficiencies, they are also reasonably prevalent among the general population. In this sample, 27 percent of the control population reported MSCs over the prior four-week period, and 34 percent reported an episode of MSC over the prior year. However, the prevalence of MSCs among those with limb absence was twice that observed in the general population, reported at 57 percent over the last four weeks and at 65 percent for at least four consecutive weeks during the prior year.
Among those with upper-limb amputations or congenital deficiencies, MSCs were most commonly experienced in the upper back and/ or neck (46 percent), followed by the sound side shoulder (33 percent) and the sound side hand (24 percent). The prevalence of MSCs in various locations is listed in Table 1 alongside similar published datasets.
An elevated prevalence of MSCs was reported both by individuals with acquired limb loss and those with congenital limb absences. While the differences observed between the two populations failed to reach statistical significance, the prevalence of MSCs among individuals with acquired amputations (59 percent) was slightly higher than that reported by those with congenital upper-limb deficiencies (54 percent). However, further analysis of the cohort suggests some additional considerations.
For example, assuming the level of limb loss affects the likelihood of eventual overuse injury, among those with congenital limb deficiencies, the level of limb loss was often distal, reported at the transradial (75 percent) and wrist disarticulation (14 percent) levels, preserving the anatomic elbow joint and some level of upper-limb function. The more debilitating limb deficiencies experienced at the transhumeral level were only observed in 12 subjects (11 percent). By contrast, among those with acquired amputations, transhumeral limb loss was predominant (47 percent), followed by transradial limb loss (30 percent) and wrist disarticulations (23 percent). This discrepancy might help explain the higher prevalence observed among those with acquired limb loss.
In addition, 70 percent of the acquired amputations were traumatic in their etiologies. That many of these were associated with blue-collar work environments is suggested by the disparate current employment rates and educational trends in the two cohorts. A lower education level was reported for nearly half of those with acquired amputations, but for only 29 percent of those with congenital absences. And, a higher education level was reported by 33 percent of those with congenital limb deficiencies, but by only 21 percent of those with acquired amputations. A corroborative finding is suggested by the fact that 65 percent of those with congenital limb deficiencies were currently employed, compared to 42 percent of those with traumatic amputations. Thus, disparities in education levels and subsequent work environments may have also contributed to the observations of the study.
Viewed collectively, despite the commonality of upper-limb absence, the two cohorts were far from matched, with marked differences in the distributions of educational attainment and levels of limb loss. Somewhat surprisingly, time since amputation appeared to be unrelated to the presence of MSCs. Additionally, within this study, neither the prevalence of MSCs nor the associated pain scores varied significantly between users and nonusers of prostheses.
When considering those individuals with limb absence who reported MSCs against those who did not, a few variables emerged. With respect to general health perceptions, those subjects who did not report MSCs reported mean general health values that were equivalent to those of the control population. By contrast, those who reported experiencing MSCs reported comparatively reduced general health. Identical trends were observed with regard to mental health. Thus, the presence and experience of painful MSCs may have more bearing on an individual's perception of his or her mental and overall general health than his or her limb absence does, a theme that will be supported by a second publication discussed later in this article.
The relationship between MSCs and employment received greater scrutiny in a second study drawn from a data subset of the Dutch cohort that included only those 207 people of employment age.2 The inclusion of some additional data points gathered in the same survey effort provides modest additional insight into the relationships between limb absence, employment rates, employment type, and MSCs.
Among this subcohort of individuals between the ages of 18 and 65, employment rates were substantially higher for those with congenital limb deficiencies (74 percent) than for those with acquired amputations (44 percent). Data analysis suggests that education, employment, and overuse MSCs are further implicated.
Reduced to those subjects of employable age, lower education levels were predominant among those with acquired amputations (44 percent), while higher education levels were predominant among those with congenital deficiencies (also 44 percent). By contrast, higher education levels were less commonly observed among those with acquired amputations (23 percent), and lower education levels were observed infrequently in those with congenital deficiencies (25 percent).
Given this distribution, it may be assumed that those with acquired amputations would largely perform physically demanding work and those with congenital deficiencies would perform more mentally demanding work. The latter assumption is borne out by the data, with 71 percent of those employed individuals with congenital limb loss working in mentally demanding vocations. However, the assumptions break down among employed individuals with acquired amputations, with 67 percent also reporting employment in mentally demanding vocations.
One speculative explanation is that those individuals with acquired amputations and medium to high education levels (n = 60) likely comprised the majority of those working in mentally demanding vocations (n = 42), while those with little or limited education (n = 48) comprised those with physically demanding vocations (n = 12) or those who had become unemployed (n = 47). This theory appears to be substantiated in an analysis of the educational levels of the unemployed individuals, where 58 percent reported limited education and only 19 percent reported a higher education level.
In addition to the role of educational differences, overuse MSCs also appeared to play a role, as the prevalence of MSCs was modestly higher among the unemployed versus employed individuals (64 percent versus 56 percent). Additionally, among the unemployed individuals, average pain levels were 17 percent greater and disability levels were 72 percent greater than for the employed individuals. Whether pain and disability precipitated unemployment or resulted from failed attempts to persist in physically demanding vocations remains a matter of speculation.
A related study from a rehabilitation center in Ljubljana, Slovenia, sought to characterize the pain experience of those patients with upper-limb absences who reported the presence of overuse injuries and compromise.3 In contrast to the postal survey methods of the previous study, the data for this report came from two years of outpatient clinic visits with a physiatrist. A smaller sample size of 65 individuals was reported upon, composed predominantly of individuals with transradial amputations (68 percent) and transhumeral amputations (17 percent). Congenital deficiencies accounted for about 20 percent of the limb absences.
The most observed overuse injury in this cohort was carpal tunnel syndrome (43 percent), followed by shoulder pain (40 percent), neck pain (29 percent), and elbow pain (20 percent). This data is summarized against similar published datasets in Table 1 above. Of note, the etiology of limb absence, whether congenital or acquired, did not appear to affect the prevalence of overuse symptoms.
Prosthetic use was generally high among the study participants, with 60 percent reporting use of their prostheses all day and an average hourly usage of more than nine hours per day. An intriguing observation was found in an analysis of the presence of carpal tunnel syndrome against the type of prostheses worn by the subjects. Carpal tunnel syndrome was not observed among those who used a myoelectric prosthesis, and only observed in one-third of those using a body-powered device.
The prevalence of carpal tunnel syndrome was higher among those with passive aesthetic devices, reported at 50 percent, and universal among those who chose not to wear a prosthesis. However, given the low numbers of both nonusers and myoelectric users, this data must be interpreted with caution.
Pain Reported During Adulthood by Those With Congenital Deficiencies
In contrast to acquired amputations, where considerations of pain include elements of phantom limb pain and persistent post-operative, limb-related pain, the pain experienced by those with congenital deficiencies appears to be primarily due to overuse injuries to the trunk and sound side limb. Against this backdrop, data from a recent Norwegian study provides additional insight into the impacts of pain for those with congenital, unilateral upper-limb deficiencies.6
Culling data from a larger survey effort of patients with any limb reduction deficiency, researchers identified 77 adult subjects with unilateral upper-limb deficiencies. Transradial-level deficiencies were predominant (53 percent), followed by hand deficiencies (22 percent), finger deficiencies (16 percent), and transhumeral-level deficiencies (9 percent).
Averaging 43 years of age, these adults were asked to complete the Short Form-36 Health Survey (SF-36) as a measure of their health-related quality of life. The instrument is made up of four mental subscales and four physical subscales. The scores of those adults with congenital limb deficiencies were compared against age- and gender-matched peers taken from the general population of Norway.
While the average scores of those with congenital deficiencies lagged significantly behind those of the general population, the discrepancy was most pronounced in the realm of bodily pain, where those with limb deficiencies scored, on average, 26 percent lower than the control group.
This observation is meaningful not only in its assertion that pain is highly prevalent in this population, but that the disparities in pain experience compared to the general population are more pronounced than those disparities associated with physical function and general health.
In addition, the authors articulate the mechanism by which such pain influences other elements of health and well-being: "We know from clinical practice that pain from overuse after several years of work may lead to both fear of worsening and further loss of function. This may explain why adults with unilateral upper-limb deficiencies ask for disability benefits and quit work before the ordinary retirement age."
The collective insights gained from these studies expand our understanding of the prevalence and impact of pain among those with upper-limb absence. While painful overuse injuries appear to be common among people with acquired amputations and with congenital deficiencies, the mechanism of development may differ between the two. Those with congenital differences are likely to have compensated for their limb differences for much longer than their peers with acquired injuries, with greater cumulative exposure to overuse. By contrast, those with acquired amputations generally have reduced educational resources and may be driven to physically demanding vocations that lead to a quicker overuse experience. In either case, available data suggests that the pain associated with overuse symptoms may be more disruptive to the overall health and well-being of the individual than the functional limitations associated with limb absence.
Phil Stevens, MEd, CPO, FAAOP, is in clinical practice with Hanger Clinic, Salt Lake City. He can be reached at .
- Postema, S. G., R. M. Bongers, M. A. Brouwers, H. Burger, L. M. Norling-Hermansson, M. F. Reneman, P. U. Dijkstra, and C. K. van der Sluis. 2016. Musculoskeletal complaints in transverse upper limb reduction deficiency and amputation in the Netherlands: Prevalence, predictors, and effect on health. Archives of Physical Medicine and Rehabilitation 97 (7):1137-45.
- Postema, S. G., R. M. Bongers, M. A. Brouwers, H. Burger, L. M. Norling-Hermansson, M. F. Reneman, P. U. Dijkstra, and C. K. van der Sluis. 2016. Upper limb absence: Predictors of work participation and work productivity. Archives of Physical Medicine and Rehabilitation 97 (6):892-9.
- Burger, H. and G. Vidmar. 2016. A survey of overuse problems in patients with acquired or congenital upper limb deficiency. Prosthetics and Orthotics International 40 (4):497-502.
- Hanley, M. A., D. M. Ehde, M. Jensen, J. Czerniecki, D. G. Smith, and L. R. Robinson. 2009. Chronic pain associated with upper-limb loss. American Journal of Physical Medicine & Rehabilitation 88 (9):742-51.
- Datta, D., K. Selvarajah, and N. Davey. 2004. Functional outcome of patients with proximal upper limb deficiency-acquired and congenital. Clinical Rehabilitation 18 (2):172-7.
- Johansen, H., K. Østlie, L. Ø. Andersen, and S. Rand-Hendriksen. 2016. Health-related quality of life in adults with congenital unilateral upper limb deficiency in Norway. A cross-sectional study. Disability and Rehabilitation 38 (23):2305-14.
- Ostlie, K., P. Magnus, O. H. Skjeldal, B. Garfelt, and K. Tambs. 2011. Mental health and satisfaction with life among upper limb amputees: A Norwegian population-based survey comparing adult acquired major upper limb amputees with a control group. Disability and Rehabilitation. 33:1594-607.