Ten-year phantom limb pain with only four sessions of Fu's subcutaneous needling: A case report and systematic review.

Phantom limb pain (PLP) is a distressing consequence commonly encountered by individuals who have undergone amputations. The efficacy of treatment options for PLP is limited. In this study, we present a case of a 64-year-old male who suffered from PLP for a duration of 10 years following an above-the-knee amputation. Despite unsuccessful attempts with painkillers and neurotrophic drugs over the course of a decade, the patient sought relief through Fu's Subcutaneous Needling (FSN), an innovative acupuncture therapy that specifically targets the subcutaneous tissue for pain management. Remarkably, the patient experienced a significant reduction in PLP and subsequently decreased his reliance on medication, as well as experiencing improved sleep after undergoing one session of FSN per day for four consecutive days. A follow-up conducted three years later demonstrated positive treatment outcomes. FSN demonstrated a significant influence on PLP, resulting in reduced analgesic requirements and enhanced quality of life. Therefore, FSN may be recommended as an additional treatment option for PLP. In order to gain a comprehensive understanding of the effects of acupuncture on PLP, a systematic review of relevant literature was conducted in PubMed, Embase, Cochrane Library and Web of Science in recent 20 years (from January 1, 2003 to October 16, 2023), using different combinations of the following terms: (phantom acrodynia), (residual limb pain), (phantom limb pain), (acupuncture), (electroacupuncture), (auriculoacupuncture), and (needling). 9 articles with 18 cases including one randomized controlled trial (n = 8) were obtained. This review provided additional evidence supporting the efficacy and safety of needling therapies for PLP. This systematic review offers additional evidence supporting the effectiveness and safety of needling therapies for PLP. However, there were no precedent reports using FSN treatment for PLP. Hence, this case may provide some implications for clinicians in practice.

Managing acute phantom limb pain with transcutaneous electrical nerve stimulation: a case report.

INTRODUCTION: Phantom limb pain is characterized by painful sensations in the amputated limb. The clinical presentation of acute phantom limb pain may differ from that of patients with chronic phantom limb pain. The variation observed implies that acute phantom limb pain may be driven by peripheral mechanisms, indicating that therapies focused on the peripheral nervous system might be successful in reducing pain. CASE PRESENTATION: A 36-year-old African male with acute phantom limb pain in the left lower limb, was treated with transcutaneous electrical nerve stimulation. CONCLUSION: The assessment results of the presented case and the evidence on acute phantom limb pain mechanisms contribute to the current body of literature, indicating that acute phantom limb pain presents differently to chronic phantom limb pain. These findings emphasize the importance of testing treatments that target the peripheral mechanisms responsible for phantom limb pain in relevant individuals with acquired amputations.

Peripheral nerve stimulation enables somatosensory feedback while suppressing phantom limb pain in transradial amputees.

To simultaneously treat phantom limb pain (PLP) and restore somatic sensations using peripheral nerve stimulation (PNS), two bilateral transradial amputees were implanted with stimulating electrodes in the proximity of the medial, ulnar and radial nerves. Application of PNS evoked tactile and proprioceptive sensations in the phantom hand. Both patients learned to determine the shape of invisible objects by scanning a computer tablet with a stylus while receiving feedback based on PNS or transcutaneous electrical nerve stimulation (TENS). Оne patient learned to use PNS as feedback from the prosthetic hand that grasped objects of different sizes. PNS abolished PLP completely in one patient and reduced it by 40-70% in the other. We suggest incorporating PNS and/or TENS in active tasks to reduce PLP and restore sensations in amputees.

Neurofeedback Training without Explicit Phantom Hand Movements and Hand-Like Visual Feedback to Modulate Pain: A Randomized Crossover Feasibility Trial.

Phantom limb pain is attributed to abnormal sensorimotor cortical representations, although the causal relationship between phantom limb pain and sensorimotor cortical representations suffers from the potentially confounding effects of phantom hand movements. We developed neurofeedback training to change sensorimotor cortical representations without explicit phantom hand movements or hand-like visual feedback. We tested the feasibility of neurofeedback training in fourteen patients with phantom limb pain. Neurofeedback training was performed in a single-blind, randomized, crossover trial using two decoders constructed using motor cortical currents measured during phantom hand movements; the motor cortical currents contralateral or ipsilateral to the phantom hand (contralateral and ipsilateral training) were estimated from magnetoencephalograms. Patients were instructed to control the size of a disk, which was proportional to the decoding results, but to not move their phantom hands or other body parts. The pain assessed by the visual analogue scale was significantly greater after contralateral training than after ipsilateral training. Classification accuracy of phantom hand movements significantly increased only after contralateral training. These results suggested that the proposed neurofeedback training changed phantom hand representation and modulated pain without explicit phantom hand movements or hand-like visual feedback, thus showing the relation between the phantom hand representations and pain. PERSPECTIVE: Our work demonstrates the feasibility of using neurofeedback training to change phantom hand representation and modulate pain perception without explicit phantom hand movements and hand-like visual feedback. The results enhance the mechanistic understanding of certain treatments, such as mirror therapy, that change the sensorimotor cortical representation.

Virtual and Augmented Reality-based Treatments for Phantom Limb Pain: A Systematic Review.

Objective: To evaluate the literature on the effectiveness of virtual reality (VR)- and augmented reality (AR)-based treatments for phantom limb pain (PLP) in postamputation or brachial plexus avulsion (BPA) populations. Methods: Multiple databases were queried in July 2021 with the keywords "virtual reality," "augmented reality," and "phantom limb pain." Included studies utilized VR or AR to treat PLP with outcome measurement. Two independent reviewers assessed methodological quality using the Physiotherapy Evidence Databsae (PEDro) Scale and the Methodological Index for Nonrandomized Studies (MINORS) scoring. Studies were separated into immersive and nonimmersive AR/VR systems, with further categorization according to the specific methodologies used. Results: Of 110 results from the database queries, 20 publications met the inclusion criteria. There was one unblinded, randomized, control trial (RCT), one single-blinded, randomized, crossover trial (RCxT), three comparative case series, 13 noncomparative case series, and two case reports. Seven of the 20 studies were classified as nonimmersive. Six studies reported decreased PLP after AR/VR treatments, of which four reported significant reductions. One study reported a reduction in PLP with no significant difference from control conditions. Thirteen of the 20 studies were classified as immersive AR/VR. Twelve studies reported decreased PLP after AR/VR treatments, of which eight reported significant reductions. One study found no change in PLP, compared to baseline. Conclusion: The number of studies using AR/VR in PLP treatment has expanded since a 2017 review on the topic. The majority of these studies offer support for the efficacy of treating PLP with AR/VR-based treatments. Research has expanded on the customization, outcome measurements, and statistical analysis of AR/VR treatments. While results are promising, most publications remain at the case series level, and clinical indications should be cautioned. With improvements in the quality of evidence, there remain avenues for further investigations, including increased sampling, randomization, optimization of treatment duration, and comparisons to alternative therapies.

A scoping review of current non-pharmacological treatment modalities for phantom limb pain in limb amputees.

PURPOSE: Phantom limb pain (PLP) is a chronic neuropathic pain condition of a missing limb following amputation. Pain management is multi-modal, including various non-pharmacological therapies. The purpose of this scoping review was to investigate the evidence surrounding current non-pharmacological treatment modalities for PLP and provide insight into their clinical feasibility. METHOD: A systematic search was conducted using four databases (Medline, Embase, PsychInfo, and CINAHL) following the PRISMA-ScR method. Results from papers meeting the inclusion criteria were charted to summarize findings, demographics, and use of neuroimaging. RESULTS: A total of 3387 papers were identified, and full texts of 142 eligible papers were assessed. Eleven treatment modalities for PLP were identified with varying levels of evidence. Overall, there were 25 RCTs, 58 case reports, and 59 a combination of pilot, quasi-experimental, observational, and other study designs. CONCLUSIONS: Currently, the evidence surrounding most treatment modalities is limited and only a fraction of studies are supported by strong evidence. The findings of this review demonstrated a clear need to conduct more rigorous research with diverse study designs to better understand which modalities provide the most benefit and to incorporate neuroimaging to better determine the neural correlates of PLP and mechanisms of various treatments.Implications for RehabilitationPhantom limb pain (PLP) is a prevalent and debilitating condition following amputation and health care professionals should incorporate an evidence-based pain management protocol into their rehabilitation program.There exist a number of different non-pharmacological therapies to address PLP, however the scientific rigor and levels of evidence vary across modalities.Prescription of interventions for PLP should consider individual patient differences, accessibility to the patient, and quite possibly, a multi-modal approach, particularly for those who also experience residual limb pain.Imagery-based therapies provide the highest level of current evidence based on robust and large randomized control trials, are readily accessible, and are thus most recommended for relief of PLP.

Contralateral Acupuncture for the Treatment of Phantom Limb Pain and Phantom Limb Sensation in Oncologic Lower Limb Amputee: A Case Report.

Phantom limb pain (PLP) and phantom limb sensation (PLS) are common and distressing sequelae of amputation. Current pain management following amputation is challenging and unsatisfying. In this case study, a 74-year-old woman underwent above-knee amputation because of the rhabdomyosarcoma in the right leg. Despite several analgesics, pain was poorly controlled. The phantom limb pain and sensation were immediately reduced by the contralateral acupuncture, and abolished after the third session with no side-effects, no relapse during the next 9 months. Contralateral acupuncture showed positive effect on PLP and PLS in this case, but more robust evidence would be needed to support the efficacy of this treatment technique for indication.

Development and Validation of a Graded Motor Imagery Intervention for Phantom Limb Pain in Patients with Amputations (GraMI Protocol): A Delphi Study.

BACKGROUND: Phantom limb pain can be defined as discomfort or pain in a missing part of the limb. The aims of this study were to develop and validate, through a Delphi methodology, a graded motor imagery protocol in order to reduce phantom limb pain. METHOD: Physiotherapists and/or occupational therapists with experience in research and a minimum clinical experience of five years in the field of neurorehabilitation and/or pain were recruited by part of a group of experts to assess the intervention. The study was conducted through an online questionnaire, where experts assessed each aspect of the intervention through a Likert scale. As many rounds as necessary were carried out until consensus was reached among experts. RESULTS: A total of two rounds were required to fully validate the intervention. During the second round, the relative interquartile range of all aspects to be assessed was less than 15%, thus showing a consensus among experts and with good concordance (Kappa index of 0.76). CONCLUSION: Experts validated a graded motor imagery intervention of phantom limb pain in patients with amputations (GraMi protocol). This intervention can help to homogenize the use of graded motor imagery in future studies and in clinical practice.

Effects of mirror therapy on phantom limb sensation and phantom limb pain in amputees: A systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: This systematic review and meta-analysis aimed to evaluate the effects of mirror therapy on phantom limb sensation and phantom limb pain in amputees. DATA SOURCES: Nine electronic databases (PubMed, EMBASE, MEDLINE, Web of Science, the Cochrane Library, CINAHL, PsycInfo, PreQuest, PEDro) were searched from their inception to May 10th, 2021. METHODS: Two authors independently selected relevant studies and extracted the data. The effect sizes were calculated under a random-effects model meta-analysis, and heterogeneity was assessed using the I2 test. The risk of bias was evaluated by the Cochrane risk of bias tool, and the methodological quality was appraised by the PEDro scale. The GRADE approach was applied to assess the confidence of the effect. RESULTS: A total of 11 RCTs involving 491 participants were included in this review and nine RCTs involving 372 participants were included in meta-analysis. The quality of these studies was from poor to good with scores ranging from 2 to 8 points according to PEDro scale. The pooled SMD showed that mirror therapy reduced the pain with a large effect size (-0.81; 95% CI = -1.36 to -0.25; P = 0.005; I2 = 82%; n = 372) compared with other methods (four covered mirror, one phantom exercise, three mental visualization, one sensorimotor exercise, one transcutaneous electrical nerve stimulation, one tactile stimuli). The quality of evidence for the outcome pain intensity was determined to be fair according to GRADE approach. CONCLUSION: There is fair-quality evidence that MT is beneficial for reducing phantom limb pain.

Electroacupuncture For Alleviation Of Phantom Limb Pain.

Phantom limb pain is clinically defined as the perception of pain or discomfort in a limb that no longer exists. Most amputees will experience phantom limb pain, which is associated with a low health-related quality of life. Phantom limb pain represents an important challenge in finding an effective therapy. The scientific evidence for best practice is weak, and is characterized by various clinical reports describing the pragmatic use of drugs and interventional techniques. Recent approaches to restore the sensory motor input have shown promise. One such technique is electroacupuncture. We report here a case study of a male in his 30s who sustained severe injuries, including a high transfemoral amputation, as a result of being hit by a car. An electroacupuncture treatment protocol was used. Over the course of 3 months, electroacupuncture alleviated the patient's phantom limb pain, minimized his use of drugs, and improved his sleep and quality of life. The effect of electroacupuncture treatment lasted for 3-4 months, and successful top-up treatment maintained his pain relief. The results are in line with a study comparing massage and electroacupuncture in patients with spinal cord injury with neurogenic pain; a limited number of patients treated with electroacupuncture were significantly alleviated of their pain for months. This case report suggests that electroacupuncture may be useful in patients with phantom limb pain.

Client buy-in: An essential consideration for graded motor imagery in hand therapy.

STUDY DESIGN: This is a cross-sectional survey research. INTRODUCTION: Current evidence provides efficacy of graded motor imagery (GMI) in chronic pain conditions but also reveals barriers to its implementation. PURPOSE OF THE STUDY: The purpose of this study was to describe current utilization of GMI in hand therapy practice. METHODS: Survey tool, informed by literature and Revised Neurophysiology of Pain Questionnaire (NPQ) was electronically distributed to members of the American Society of Hand Therapists. RESULTS: 132 therapists completed the survey. 65.2% reported they would always or very likely use GMI in clients with central sensitization, but no relationship between the likelihood of therapists using GMI to score achieved on the NPQ was found. Lack of patient buy-in, was the main barrier cited. "Sell it well" with pain neuroscience education the most cited strategy. DISCUSSION: GMI is frequently used in clients with central sensitization but requires client buy-in. CONCLUSIONS: Understanding and explaining pain mechanism is essential for implementing GMI.

Effect of Myofascial Trigger Points Electric Stimulation on Phantom Limb Pain after Lower Limb Amputation / 中国康复理论与实践

Objective:To explore the clinical efficacy of myofascial trigger point electric stimulation based on mirror therapy on phantom limb pain after lower limb amputation. Methods:From May to November, 2020, 50 patients with phantom limb pain after lower limb amputation were randomly divided into control group (n = 25) and experiment group (n = 25). Both groups accepted mirror therapy, while the experiment group received myofascial trigger point electric stimulation before mirror therapy, for four weeks. They were assessed with short-form of McGill Pain Questionnaire (SF-MPQ), Pittsburgh Sleep Quality Index (PSQI), Hamilton Anxiety Scale (HAMA), Timed 'Up & Go' Test (TUGT) and 6-minute walk test (6MWT) before and after treatment. Results:All the indexes improved in both groups after treatment (|t| > 8.210, P < 0.001), and improved more in the experiment group than in the control group (|t| > 5.103, P < 0.001), except the present pain intensity of SF-MPQ. Conclusion:Mirror therapy is effective on phantom limb pain after lower limb amputation in terms of pain, sleep, anxiety and walking, and the effect could be stronger after myofascial trigger point electric stimulation.

The effectiveness of graded motor imagery for reducing phantom limb pain in amputees: a randomised controlled trial.

OBJECTIVE: To investigate whether graded motor imagery (GMI) is effective for reducing phantom limb pain (PLP) in people who have undergone limb amputations. DESIGN: A single-blinded randomised, controlled trial. SETTING: Physiotherapy out-patient departments in three secondary level hospitals in Cape Town, South Africa. PARTICIPANTS: Twenty-one adults (≥18 years) who had undergone unilateral upper or lower limb amputations and had self-reported PLP persisting beyond three months. INTERVENTIONS: A 6-week GMI programme was compared to routine physiotherapy. The study outcomes were evaluated at baseline, 6 weeks, 3 months and 6 months. OUTCOME MEASURES: The pain severity scale of the Brief Pain Inventory (BPI) was used to assess the primary outcome - PLP. The pain interference scale of the BPI and the EuroQol EQ-5D-5L were used to assess the secondary outcomes - pain interference with function and health-related quality of life (HRQoL) respectively. RESULTS: The participants in the experimental group had significantly greater improvements in pain than the control group at 6 weeks and 6 months. Further, the participants in the experimental group had significantly greater improvements than the control group in pain interference at all follow-up points. There was no between-group difference in HRQoL. CONCLUSION: The results of the current study suggest that GMI is better than routine physiotherapy for reducing PLP. Based on the significant reduction in PLP and pain interference within the participants who received GMI, and the ease of application, GMI may be a viable treatment for treating PLP in people who have undergone limb amputations. CLINICAL TRIAL REGISTRATION NUMBER: (PACTR201701001979279).

Comparison of Relative Benefits of Mirror Therapy and Mental Imagery in Phantom Limb Pain in Amputee Patients at a Tertiary Care Center.

OBJECTIVE: To determine the relative benefit of mirror therapy and mental imagery in phantom limb pain. DESIGN: Prospective randomized controlled trial. SETTING: Physical Medicine and Rehabilitation Department, All India Institute of Medical Sciences, Patna. PARTICIPANTS: Amputees (N=92) with no significant difference in baseline characteristics. There was a male predominance in both groups (mirror therapy: 36 men, 10 women; mental imagery: 37 men, 9 women). INTERVENTION: Patients of both groups underwent a conventional amputee rehabilitation program and daily treatment of either mirror therapy or mental imagery on a regular basis, first in a rehabilitation care unit and later at home. MAIN OUTCOME MEASURES: Phantom limb pain (PLP) was measured by visual analog scale (VAS) score at baseline (0) and at 4, 8, and 12 months. RESULTS: This study included 92 patients ranging in age from 12 to 75 years (average, 34.79y). There was no significant difference in VAS score between the groups at baseline, but we found a significant reduction of pain in both groups at follow-up. However, upon comparing the improvement in both groups, we determined that the mirror therapy group had better improvement (from 7.07±1.74 to 2.74±0.77) compared with the mental imagery group (from 7.85±0.76 to 5.87±1.41). CONCLUSIONS: Mirror therapy and mental imagery are both good and cost-effective rehabilitation aids for amputee patients to reduce PLP, but mirror therapy appears to be more effective than mental imagery.

Recent advances in understanding and managing phantom limb pain.

Post-amputation phantom limb pain (PLP) is highly prevalent and very difficult to treat. The high-prevalence, high-pain intensity levels, and decreased quality of life associated with PLP compel us to explore novel avenues to prevent, manage, and reverse this chronic pain condition. This narrative review focuses on recent advances in the treatment of PLP and reviews evidence of mechanism-based treatments from randomized controlled trials published over the past 5 years. We review recent evidence for the efficacy of targeted muscle reinnervation, repetitive transcranial magnetic stimulation, imaginal phantom limb exercises, mirror therapy, virtual and augmented reality, and eye movement desensitization and reprocessing therapy. The results indicate that not one of the above treatments is consistently better than a control condition. The challenge remains that there is little level 1 evidence of efficacy for PLP treatments and most treatment trials are underpowered (small sample sizes). The lack of efficacy likely speaks to the multiple mechanisms that contribute to PLP both between and within individuals who have sustained an amputation. Research approaches are called for to classify patients according to shared factors and evaluate treatment efficacy within classes. Subgroup analyses examining sex effects are recommended given the clear differences between males and females in pain mechanisms and outcomes. Use of novel data analytical approaches such as growth mixture modeling for multivariate latent classes may help to identify sub-clusters of patients with common outcome trajectories over time.

Treatment Strategies and Effective Management of Phantom Limb-Associated Pain.

PURPOSE OF REVIEW: Phantom sensations are incompletely understood phenomena which take place following an amputation or deafferentation of a limb. They can present as kinetic, kinesthetic, or exteroceptive perceptions. It is estimated that phantom limb pain (PLP) affects anywhere from 40 to 80% of amputees. RECENT FINDINGS: Psychiatric illnesses such as depression, anxiety, and mood disorders have higher prevalence in amputees than in the general population. Pharmacologic treatment has been used as first-line therapy for amputees suffering from PLP with agents including gabapentinoids, amitriptyline, and other tricyclic anti-depressants, opioids, and local anesthetics. Non-invasive treatment modalities exist for PLP including sensory motor training, mirror visual therapy, and non-invasive neuromodulation. Non-invasive neuromodulation includes interventions like transcutaneous electrical nerve stimulation (TENS) and transcranial magnetic stimulation. While many promising therapies for PLP exist, more clinical trials are required to determine the efficacy and protocols needed for maximum benefit in patients suffering from PLP.

Targeted muscle reinnervation in oncologic amputees: Early experience of a novel institutional protocol.

BACKGROUND: We describe a multidisciplinary approach for comprehensive care of amputees with concurrent targeted muscle reinnervation (TMR) at the time of amputation. METHODS: Our TMR cohort was compared to a cross-sectional sample of unselected oncologic amputees not treated at our institution (N = 58). Patient-Reported Outcomes Measurement Information System (NRS, PROMIS) were used to assess postamputation pain. RESULTS: Thirty-one patients underwent amputation with concurrent TMR during the study; 27 patients completed pain surveys; 15 had greater than 1 year follow-up (mean follow-up 14.7 months). Neuroma symptoms occurred significantly less frequently and with less intensity among the TMR cohort. Mean differences for PROMIS pain intensity, behavior, and interference for phantom limb pain (PLP) were 5.855 (95%CI 1.159-10.55; P = .015), 5.896 (95%CI 0.492-11.30; P = .033), and 7.435 (95%CI 1.797-13.07; P = .011) respectively, with lower scores for TMR cohort. For residual limb pain, PROMIS pain intensity, behavior, and interference mean differences were 5.477 (95%CI 0.528-10.42; P = .031), 6.195 (95%CI 0.705-11.69; P = .028), and 6.816 (95%CI 1.438-12.2; P = .014), respectively. Fifty-six percent took opioids before amputation compared to 22% at 1 year postoperatively. CONCLUSIONS: Multidisciplinary care of amputees including concurrent amputation and TMR, multimodal postoperative pain management, amputee-centered rehabilitation, and peer support demonstrates reduced incidence and severity of neuroma and PLP.

Pain management in new amputees: a nursing perspective.

Phantom limb pain (PLP) is a widespread and challenging neuropathic pain problem, occurring after both surgical and traumatic amputation of a limb. It may occur immediately after surgery or some months later, however, most cases it presents within the first 7 postoperative days. Patients report a range of pain characteristics in the absent limb, including burning, cramping, tingling and electric shock sensation. The incidence of PLP has been reported to be between 50% and 85% following amputation. Its management is notoriously difficult, with no clear consensus on optimal treatment. It is often resistant to classic balanced analgesia and typical neuropathic pain medications. Taking into account these issues, the authors aimed to improve the management of patients undergoing amputation at their institution, by ensuring accurate and holistic assessment, the selection of suitable interventions through critical analysis and synthesis of available evidence, and the appropriate evaluation and adaptation of treatment plans, to ensure patients achieved their individualised goals.

Phantom limb pain: peripheral neuromodulatory and neuroprosthetic approaches to treatment.

Post-amputation phantom limb pain (PLP) is a widespread phenomenon that can have physical, psychological, and functional impacts on amputees who experience the condition. The varying presentations and mechanisms of PLP make it difficult to effectively provide long-term pain relief. Multiple neuromodulatory approaches to treating PLP have focused on electrical stimulation of the peripheral nervous system, with varying degrees of success. More recently, research has been done to study the effects of neuroprosthetic approaches on PLP. Neuroprosthetics combine the use of a functional prosthetic with stimulation to the peripheral nerves in the residual limb. Although many of the neuroprosthetic studies focus on improving function, several have shown preliminary evidence for the reduction of severity of PLP. In this review we provide an overview of the current understanding of the neurological mechanisms that initiate and sustain PLP, as well as the neuromodulatory and neuroprosthetic approaches under development for treatment of the condition. Muscle Nerve 59:154-167, 2019.

Patient care for postamputation pain and the complexity of therapies: living experiences.

AIM: Limb amputation traumatically alters body image. Sensations rapidly prevail that the limb is still present and 85% of patients portray phantom limb pain. Throughout the testimonies of amputated patients with intense phantom limb pain, we show the difficulty in treating this chronic pain with current pharmacological and nonpharmacological therapies. PATIENTS & METHODS: We qualitatively analyzed the therapeutic choices of five amputees, the effectiveness of the treatments chosen and the impact on patients' quality-of-life. RESULTS & CONCLUSION: In general, patients who are refractory to pharmacological treatments are in favor of trying alternative therapies. It is therefore crucial to design a combined and personalized therapeutic plan under the coordination of a multidisciplinary team for the wellbeing of the patient.