The effects of graded motor imagery and its components on phantom limb pain and disability in upper and lower limb amputees: a systematic review protocol

Feasibility study of a home-based graded motor imagery intervention (GraMI protocol) for amputees with phantom limb pain

INTRODUCTION

Phantom limb pain affects 64% of amputees. Graded Motor Imagery comprises three consecutive application techniques designed to reorganize maladaptive changes that have occurred after the amputation.

OBJECTIVE

To assess the feasibility of a home-based Graded Motor Imagery intervention, the GraMI protocol, for amputee people with phantom limb pain.

METHODS

Twenty individuals over 18 years of age with upper or lower limb amputation, experiencing phantom limb pain, who were pharmacologically stable, and had been discharged from the hospital were recruited. The experimental group followed the GraMI protocol. Primary outcomes included study processes, such as recruitment time and rate, adherence, compliance, and the acceptability of digital technologies as a treatment tool. Secondary outcomes assessed the impact on phantom limb pain, quality of life, functionality, and depressive symptoms.

RESULTS

On average, seven participants were recruited monthly over a three-month period. No losses were recorded throughout the nine weeks of intervention. Treatment adherence averaged 89.32%, and all participants demonstrated familiarity with the usability of digital technologies. No significant differences were observed between groups (p = .054). However, within the experimental group, intragroup analysis revealed a significant (p = .005) and clinically relevant reduction (>2 points) with a large effect size (0.89) in phantom limb pain.

CONCLUSION

Conducting a multicenter study with a home-based intervention using the GraMI protocol is feasible. Future clinical trials are needed to verify its effectiveness in managing phantom limb pain.

Case Report: Phantom limb pain relief after cognitive multisensory rehabilitation

Introduction

Relieving phantom limb pain (PLP) after amputation in patients resistant to conventional therapy remains a challenge. While the causes for PLP are unclear, one model suggests that maladaptive plasticity related to cortical remapping following amputation leads to altered mental body representations (MBR) and contributes to PLP. Cognitive Multisensory Rehabilitation (CMR) has led to reduced pain in other neurologic conditions by restoring MBR. This is the first study using CMR to relieve PLP.

Methods

A 26-year-old woman experienced excruciating PLP after amputation of the third proximal part of the leg, performed after several unsuccessful treatments (i.e., epidural stimulator, surgeries, analgesics) for debilitating neuropathic pain in the left foot for six years with foot deformities resulting from herniated discs. The PLP was resistant to pain medication and mirror therapy. PLP rendered donning a prosthesis impossible. The patient received 35 CMR sessions (2×/day during weekdays, October-December 2012). CMR provides multisensory discrimination exercises on the healthy side and multisensory motor imagery exercises of present and past actions in both limbs to restore MBR and reduce PLP.

Results

After CMR, PLP reduced from 6.5-9.5/10 to 0/10 for neuropathic pain with only 4-5.5/10 for muscular pain after exercising on the Numeric Pain Rating Scale. McGill Pain Questionnaire scores reduced from 39/78 to 5/78, and Identity (ID)-Pain scores reduced from 5/5 to 0/5. Her pain medication was reduced by at least 50% after discharge. At 10-month follow-up (9/2013), she no longer took Methadone or Fentanyl. After discharge, receiving CMR as outpatient, she learned to walk with a prosthesis, and gradually did not need crutches anymore to walk independently indoors and outdoors (9/2013). At present (3/2024), she no longer takes pain medication and walks independently with the prosthesis without assistive devices. PLP is under control. She addresses flare-ups with CMR exercises on her own, using multisensory motor imagery, bringing the pain down within 10-15 min.

Conclusion

The case study seems to support the hypothesis that CMR restores MBR which may lead to long-term (12-year) PLP reduction. MBR restoration may be linked to restoring accurate multisensory motor imagery of the remaining and amputated limb regarding present and past actions.

The effectiveness of graded motor imagery and its components on phantom limb pain in amputated patients: A systematic review

BACKGROUND

Phantom limb pain (PLP) can be defined as pain in a missing part of the limb. It is reported in 50%-80% of people with amputation.

OBJECTIVES

To provide an overview of the effectiveness of graded motor imagery (GMI) and the techniques which form it on PLP in amputees.

STUDY DESIGN

Systematic review.

METHODS

Two authors independently selected relevant studies, screened the articles for methodological validity and risk of bias, and extracted the data. Inclusion criteria used were clinical studies, written in English or Spanish, using GMI, laterality recognition, motor imagery, mirror therapy, or a combination of some of them as an intervention in amputated patients, and one of the outcomes was PLP, and it was assessed using a validated scale. The databases used were PubMed, Scopus, Web of Science, CINAHL, and PEDro.

RESULTS

Fifteen studies were included in the review. After the intervention, all the groups in which the GMI or one of the techniques that comprise it was used showed decrease in PLP.

CONCLUSION

The 3 GMI techniques showed effectiveness in decreasing PLP in amputees, although it should be noted that the application of the GMI showed better results.

Does graded motor imagery benefit individuals with knee pain: A systematic review and meta-analysis

OBJECTIVE

Evaluate how Graded Motor Imagery (GMI) may be used in those with knee pain, if individuals with knee pain present with a central nervous system (CNS) processing deficit, and if GMI is associated with improved outcomes.

METHODS

An electronic database search was conducted of PubMed, SPORTDiscus, CINHAL, MEDLINE, Google Scholar, and Sports Medicine Education Index using keywords related to GMI and knee pain. This review was reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Out of the 13,224 studies reviewed, 14 studies were included that used GMI for knee pain. Effect sizes were reported with standardized mean differences (SMD).

RESULTS

Individuals with knee osteoarthritis demonstrated poor performance with correctly identifying images of left or right knees, and GMI improved performance. In contrast, individuals with an anterior cruciate ligament injury demonstrated no evidence of CNS processing deficit and mixed outcomes with GMI. Meta-analysis was limited to individuals post total knee arthroplasty showing low certainty that GMI can improve quadriceps force production [SMD 0.64 (0.07,1.22)], but evidence of no effect to reduce pain or improve Timed up and Go performance and self-reported function.

CONCLUSIONS

Graded motor imagery may be an effective intervention for individuals with knee osteoarthritis. However, there was limited evidence that GMI was effective for an anterior cruciate ligament injury.

The Efficacy of Graded Motor Imagery and Its Components on Phantom Limb Pain and Disability: A Systematic Review and Meta-Analysis

Introduction

Graded Motor Imagery (GMI) is a non-invasive and inexpensive therapy used to treat Phantom Limb Pain (PLP) by sequentially activating motor networks in such a way that movement and pain are unpaired. The objective of this systematic review was to critically appraise relevant data on the efficacy of GMI and its components for reducing PLP and disability in amputees.

Methods

We searched 11 electronic databases for controlled trials investigating GMI and its components in amputees with PLP from inception until February 2023. Two reviewers independently screened studies and extracted relevant data. Study-level data were entered using the inverse variance function of the Review Manager 5 and pooled with the random effects model.

Results

Eleven studies with varying risk of bias were eligible. No eligible study considered left/right judgement tasks in isolation. Studies showed no effect for imagined movements, but positive effects were seen for GMI [weighted mean difference: -21.29 (95%CI: -31.55, -11.02), I2= 0%] and mirror therapy [weighted mean difference: -8.55 (95%CI: -14.74, -2.35, I2= 61%]. A comparison of mirror therapy versus sham showed no difference [weighted mean difference: -4.43 (95%CI: -16.03, 7.16), I2= 51%].

Conclusion

Our findings suggest that GMI and mirror therapy may be effective for reducing PLP. However, this conclusion was drawn from a limited body of evidence, and the certainty of the evidence was very low. Therefore, rigorous, high-quality trials are needed to address the gap in the literature and inform practice.

Relationship between phantom limb pain, function, and psychosocial health in individuals with lower-limb loss

INTRODUCTION

The adverse influence of chronic pain on function and psychological health in the general population is well understood. However, the relationship between phantom limb pain (PLP) after limb loss with function and psychological health is less clear. The study purpose was to assess the influences of PLP presence and intensity on function and psychosocial health in individuals with lower-limb loss (LLL).

METHODS

One hundred two individuals with major LLL completed a study-specific questionnaire on the presence and intensity of their PLP. The Patient-Reported Outcomes Measurement Information System -29 questionnaire was also administered.

RESULTS

Of 102 participants, 64% reported PLP, with a mean intensity of 4.8 ± 2.3 out of 10. Individuals with vs. without PLP demonstrated significantly greater sleep disturbances ( p = 0.03), whereas the differences in function, fatigue, pain interference, depressive symptoms, anxiety, or ability to participate in social roles and activities were not statistically different between groups ( p > 0.05). Of note, mean scores for many of the Patient-Reported Outcomes Measurement Information System-29 short forms among the current sample were similar to the mean of the general population, minimizing the potential clinical impact of PLP on these domains.

CONCLUSIONS

Our findings indicate a lack of meaningful associations between PLP presence or intensity with function, and psychosocial health among individuals with LLL. These findings conflict with previous research suggesting an adverse relationship between PLP, function, and psychosocial health after limb loss.

The effects of motor imagery on trapeziometacarpal osteoarthritis in women during the post-surgical immobilisation period: A protocol for a randomised clinical trial

Background:

Trapeziometacarpal osteoarthritis is the second most frequent degenerative hand disease and is the most functionally debilitating. The condition presents in 66% of women over 55. Motor imagery (MI) training post-surgery could help reduce rehabilitation times.

Method:

It is an experimental, prospective, longitudinal, parallel arm randomised clinical trial. Participants were women over 50 years old on the surgical waiting list. The experimental group will undergo MI training during the 3-week post-surgical immobilisation period. The control group will receive standard rehabilitation treatment. Outcomes will be assessed four times throughout the study using the Disabilities of the Arm, Shoulder and Hand questionnaire, the Cochin Hand Function Scale questionnaire, the Visual Analogue Scale, goniometry, baseline pinch gauge, circumferential measurement (cm), the Modified Kapandji Index and the Kinaesthetic and Visual Imagery questionnaire.

Discussion:

Early MI could improve hand function leading to improvements in recovery times.

Trial registration:

Clinical Trials registration: NCT03815734. Ethics Committee approval: 17155. Project funded in 2021.

Role of Occupational Therapy in Pain Management

This new position statement from the American Occupational Therapy Association (AOTA) describes occupational therapy's role in pain management. AOTA asserts that occupational therapy practitioners are distinctly prepared to work independently and to contribute to interprofessional teams in the treatment of pain. Practitioners strive to ensure active engagement in meaningful occupations for clients at risk for and affected by pain.

Role of Occupational Therapy in Pain Management

The American Occupational Therapy Association (AOTA) asserts that occupational therapists and occupational therapy assistants, collectively referred to as occupational therapy practitioners (AOTA, 2020b), are distinctly prepared to work independently and to contribute to interprofessional teams in the treatment of pain. Occupational therapy practitioners work to ensure active engagement in meaningful occupations for "persons, groups, or populations (i.e., the client)" (AOTA, 2020b, p. 1) at risk for and affected by pain.

Effectiveness of mental simulation practices after total knee arthroplasty in patients with knee osteoarthritis: A systematic review and meta-analysis of randomized controlled trials

Mental simulation practices, such as motor imagery, action observation, and guided imagery, have been an intervention of interest in neurological and musculoskeletal rehabilitation. Application of such practices to postoperative patients in orthopedics, particularly after total knee arthroplasty, has resulted in favorable physical function outcomes. In this systematic review and meta-analysis, we wish to determine the effectiveness of mental simulation practices with standard physical therapy compared to standard physical therapy alone in patients who underwent total knee arthroplasty in terms of postoperative pain, physical functions, and patient-reported outcome measures. We identified randomized controlled trials from inception to August 28, 2021, by using the PubMed, Cochrane Library, EMBASE, and Scopus databases. Data collection was completed on August 28, 2021. Finally, eight articles (249 patients) published between 2014 and 2020 were included. The meta-analysis revealed that mental simulation practices caused more favorable results in pain [standardized mean difference = -0.42, 95% confidence interval (CI) (-0.80 to -0.04), P = 0.03], range of motion [0.55, 95% CI (0.06-1.04), P = 0.03], maximal strength of quadriceps [1.21, 95% CI (0.31-2.12), P = 0.009], and 36-Item Short-Form Survey [0.53, 95% CI (0.14-0.92), P = 0.007]. Our data suggest that mental simulation practices may be considered adjunctive to standard physiotherapy after total knee arthroplasty in patients with knee osteoarthritis.

Motor Imagination of Lower Limb Movements at Different Frequencies

Motor imagination (MI) is the mental process of only imagining an action without an actual movement. Research on MI has made significant progress in feature information detection and machine learning decoding algorithms, but there are still problems, such as a low overall recognition rate and large differences in individual execution effects, which make the development of MI run into a bottleneck. Aiming at solving this bottleneck problem, the current study optimized the quality of the MI original signal by “enhancing the difficulty of imagination tasks,” conducted the qualitative and quantitative analyses of EEG rhythm characteristics, and used quantitative indicators, such as ERD mean value and recognition rate. Research on the comparative analysis of the lower limb MI of different tasks, namely, high-frequency motor imagination (HFMI) and low-frequency motor imagination (LFMI), was conducted. The results validate the following: the average ERD of HFMI (−1.827) is less than that of LFMI (−1.3487) in the alpha band, so did (−3.4756 < −2.2891) in the beta band. In the alpha and beta characteristic frequency bands, the average ERD of HFMI is smaller than that of LFMI, and the ERD values of the two are significantly different (p=0.0074 < 0.01; r = 0.945). The ERD intensity STD values of HFMI are less than those of LFMI. which suggests that the ERD intensity individual difference among the subjects is smaller in the HFMI mode than in the LFMI mode. The average recognition rate of HFMI is higher than that of LFMI (87.84% > 76.46%), and the recognition rate of the two modes is significantly different (p=0.0034 < 0.01; r = 0.429). In summary, this research optimizes the quality of MI brain signal sources by enhancing the difficulty of imagination tasks, achieving the purpose of improving the overall recognition rate of the lower limb MI of the participants and reducing the differences of individual execution effects and signal quality among the subjects.

Sequential neural activity in sensorimotor area and mirror neural system for graded mirror therapy with imagined hand movements

BACKGROUND

Graded motor imagery (GMI) therapy is a neural rehabilitative physiotherapy that has been shown to alleviate the severity of complex regional pain syndrome, phantom limb pain and disability.

OBJECTIVE

To identify neural networks associated with the use of graded mirror therapy (MT) while imagining hand movements.

METHODS

We made a block-design functional magnetic resonance imaging study of MT included three experiments: (1) immobile unimanual MT (IU-MT), in which the right hand flexed and made a fist, which then remained immobile; (2) mobilization unimanual MT (MU-MT), in which the right hand performed a flexion-extension movement; and (3) mobilization bimanual MT (MB-MT), in which both hands performed a flexion-extension movement. When subjects started their hand movements, they gazed at the mirror and imagined the same movement behind the mirror.

RESULTS

We discovered that the sensorimotor area of the left brain, superior temporal gyrus/middle temporal gyrus (STG/MTG) of the right brain and visual areas were activated by IU-MT. In MU-MT, only the STG/MTG was activated. Furthermore, MB-UT mostly activated the sensorimotor area and STG of the right brain. However, there were no brain areas activated by MU-MT compared with IU-MT or MB-MT; but, MB-MT activated more motor areas than IU-MT. Importantly, we determined that the level of mirror imagery was negatively correlated with signals in the mirror neuron system (MNS) and positively related with the signals in the sensorimotor areas.

CONCLUSIONS

We suggest that graded MT might be a sequential therapeutic program that can enhance the sensorimotor cortex. The MNS might have an initiating role in graded MT. Thus, there is the possibility that graded MT is a helpful treatment strategy for the rehabilitation of dysfunctional patients.

How Children with Congenital Limb Deficiencies Visually Attend to Their Limbs and Prostheses: Eye Tracking of Displayed Still Images and Visuospatial Body Knowledge

Purpose: This study aimed to clarify how children with congenital limb deficiencies visually attend to their bodies, particularly their limbs and prostheses.Methods: Participants included children with and without congenital limb deficiencies. They were shown photographs of themselves and their visual attention was measured using an eye tracker.Results: Six children with lower limb deficiencies (age [mean ± SD]: 8.8 ± 2.9; 2 girls and 4 boys), six children with upper limb deficiencies (age: 7.0 ± 2.3; 2 girls and 4 boys), and ten control children (age: 7.7 ± 1.9; 5 girls and 5 boys) were included. Children with congenital upper/lower limb deficiencies looked at their upper/lower limbs as often or more than the control children. Prompts to direct their visual attention to their limbs had limited efficacy.Conclusions: To improve the body knowledge of limbs, approaches other than visual recognition prompting, such as improving linguistic understanding, might be considered.

Mental Imagery as a Rehabilitative Therapy for Neuropathic Pain in People With Spinal Cord Injury: A Randomized Controlled Trial

BACKGROUND

Pain of neuropathic origin in spinal cord injury (SCI) is unbearable and challenging to treat. Research studies conducted in the past have shown that mental imagery (MI) techniques have a significant impact on the reduction of symptoms of central neuropathic pain in people with SCI.

OBJECTIVES

The objective of this study was to evaluate the effect of MI training on pain intensity, neuropathic pain symptoms, and interference of pain with function in SCI.

METHODS

A total of 42 SCI participants with central neuropathic pain (duration 6-12 months) were recruited and randomly allocated to MI or control groups. A MI training protocol was administered to MI group and for 30 min/d for 5 days. Outcome measures were assessed at baseline and at the end of 4 weeks.

RESULTS

There was significant reduction in differences of mean [95% CI] scores of numeric rating scale (-2.1 [CI -2.78 to -1.41]; P < .001) between groups. Mean [95% CI] total scores of Neuropathic Pain Symptom Inventory declined in MI group as compared with control group (-4.52 [CI -5.86 to -3.18]; P < .001). Similarly, Brief Pain Inventory interference scale total dropped significantly (P < .001) in MI group. Majority of participants in the MI group (55%) reported improvement in scores of Patients' Global Impression of Change scale as compared with control group where most of the participants (52%) reported no change.

CONCLUSIONS

This study shows the effectiveness of the MI protocol developed as a rehabilitative approach in improving central neuropathic pain in SCI. Trial Registration. Clinical Trials Registry-India under Indian Council of Medical Research; CTRI/2018/07/014884. Registered July 16, 2018.

Comparative study of observed actions, motor imagery and control therapeutic exercise on the conditioned pain modulation in the cervical spine: a randomized controlled trial

Aim: The aim of this study was to compare the effects of cervical exercise, motor imagery (MI) and action observation (AO) of cervical exercise actions on conditioned pain modulation and pressure pain thresholds. The second objective was to assess the effects of these interventions on cervical motor activity (ranges of motion and muscle endurance), attention, and the ability to generate motor images.Study design: Single-blinded randomized controlled trial.Materials and methods: Fifty-four healthy subjects were randomly assigned to each group. Response conditioned pain modulation, pressure pain threshold, were the main variables. The secondary outcome measures included, cervical range of motion, Neck flexor endurance test, mental movement representation associated and psychosocial variables.Results: All groups showed significant differences in time factor for all evaluated variables (p < .01) except pressure pain threshold over the tibial region. The post hoc analysis revealed significant within-group differences in the AE and AO groups in conditioned pain modulation (p < .05), with medium effect size in time [AE (d -0.61); AO (d -0.74)].Conclusion: The results showed that within-group changes in conditioned pain modulation, cervical muscle endurance, and attention where founded only in the AE and AO groups. Variations in pain thresholds at pressure in the trapezium area were also obtained in the three groups. Changes in the ranges of flexion-extension and rotation movement were presented exclusively in the exercise group, and in the capacity to generate motor images only in the AO group. However, there was no difference in the pressure pain threshold over the tibial region.

Effectiveness of the graded motor imagery to improve hand function in patients with distal radius fracture: A randomized controlled trial

STUDY DESIGN

Single-blinded randomized controlled trial.

INTRODUCTION

Pain management is essential in the early stages of the rehabilitation of distal radius fractures (DRFx). Pain intensity at the acute stage is considered important for determining the individual recovery process, given that higher pain intensity and persistent pain duration negatively affect the function and cortical activity of pain response. Graded motor imagery (GMI) and its components are recent pain management strategies, established on a neuroscience basis.

PURPOSE OF THE STUDY

To investigate the effectiveness of GMI in hand function in patients with DRFx.

METHODS

Thirty-six participants were randomly allocated to either GMI (n = 17; 52.59 [9.8] years) or control (n = 19; 47.16 [10.5] years) groups. The GMI group received imagery treatment in addition to traditional rehabilitation, and the control group received traditional rehabilitation for 8 weeks. The assessments included pain at rest and during activity using the visual analog scale, wrist and forearm active range of motion (ROM) with universal goniometer, grip strength with the hydraulic dynamometer (Jamar; Bolingbrook, IL), and upper extremity functional status using the Disability of the Arm, Shoulder and Hand Questionnaire, and the Michigan Hand Questionnaire. Assessments were performed twice at baseline and at the end of the eighth week.

RESULTS

The GMI group showed greater improvement in pain intensity (during rest, 2.24; activity, 6.18 points), wrist ROM (flexion, -40.59; extension, -45.59; radial deviation, -25.59; and ulnar deviation, -26.77 points) and forearm ROM (supination, -43.82 points), and functional status (Disability of the Arm, Shoulder and Hand Questionnaire, 38.00; Michigan Hand Questionnaire, -32.53 points) when compared with the control group (for all, P < .05).

CONCLUSION

The cortical model of pathological pain suggests new strategies established on a neuroscience basis. These strategies aim to normalize the cortical proprioceptive representation and reduce pain. One of these recent strategies, GMI appears to provide beneficial effects to control pain, improve grip strength, and increase upper extremity functions in patients with DRFx.

Functional rehabilitation of a person with transfemoral amputation through guided motor imagery: a case study

Background: Motor imagery (MI) is a mental technique, absent of physical movement, to foster movement patterns and relieve pain via a training model enacting the brain before the body. This case study assessed MI's efficacy in decreasing phantom limb pain and attaining functional gait and balance after lower extremity amputation. Description: The participant was a 71-year-old female with a transfemoral amputation seven years prior. She required a standard walker for ambulation. The participant underwent three sessions per week for four weeks of MI intervention, with immediate, post-test, and 1-week retention testing involving subjective and functional assessments. Intervention sessions involved quiet sitting with eyes closed while listening to the MI script. The scripts focused on functional movement patterns and tasks that were relevant to the participant, such as walking, balancing, and reaching. Each session's script focused on a different task. These scripts guided her through proper action and biomechanics of the skills to imagine herself moving safely and functionally. Outcomes: Short Form Berg Balance Scale and Tinetti Performance Oriented Mobility Assessment scores demonstrated clinically important and sustained improvement. Further, the participant reported decreased phantom limb pain and could walk a short distance independently for the first time in seven years. Discussion: MI is a time- and cost-effective, low-risk treatment option that decreased phantom pain and improved balance and functional gait in an individual with an amputation. The use of MI as an intervention for the rehabilitation of persons with amputation must be further examined.

Body knowledge in children with congenital lower limb deficiency

BACKGROUND

In order to effectively improve motor function, a sound understanding of one's body - for example, relative spatial position, relationships, names and functions of body parts - is essential. The aim of this study was to explore how children with congenital lower limb deficiency (LLD) perceive their bodies, particularly their legs.

METHODS

Six children with congenital LLD and 14 controls, aged 5-12 years, were recruited for this study. They drew self-portraits and answered questions about names of body parts. These body part-related questions consisted of a production test, in which an examiner pointed to body parts on each child and asked the child to name them, and a comprehension test, in which the examiner mentioned body parts and asked the child to point to them on their own body.

RESULTS

No differences were found between the self-portraits of children with LLD and those of the control children. In the verbal tests, children with LLD responded correctly at lower rates to questions on body trunk, upper limbs, arms, hands and feet than the control children.

CONCLUSION

Children with LLD have diminished lexical-semantic body knowledge of the upper limbs and feet compared with children without LLD.

Management of lower limb amputations

The most common reason for lower limb amputations in the UK is peripheral arterial disease. A thoughtful approach to surgery, with consideration of optimal amputation level and residual limb shape, can improve prosthetic use and functional outcomes. Prosthesis socket design and fit, as well as use of appropriate components, must be considered in accordance with the patient's activity level and potential. Major developments in prosthetics over the past 20 years, particularly in the area of joint design, including microprocessor knees, have increased options to improve ambulation. This is particularly significant among those with more proximal amputations, for whom energy expenditure on walking is even greater. Management of post-amputation pain syndromes including phantom limb pain can prove challenging, although there are novel options for pain control. Long-term care of both the residual and contralateral limbs is paramount to reduce risk of further amputation surgery, and optimize longer term function and quality of life.