Postamputation Pain, Lower Limb Amputation, Combat Trauma
Conditions
Keywords
Acute Post-Amputation Pain, BAMS, Early Mobilization, Opioid Consumption, Regional Anesthesia, Military Trauma, Lower Limb Amputation, Combat-Related Injury, Continuous Peripheral Nerve Block, Perineural cetheter, Cryoablation
Brief summary
Acute post-amputation pain remains a significant clinical challenge in patients with combat-related lower limb injuries and may negatively affect early rehabilitation, mobility, and opioid consumption. Various regional analgesia techniques and cryoanalgesia have been proposed to improve pain control; however, evidence regarding their feasibility and clinical utility in military trauma populations remains limited. The aim of this pilot study is to assess the feasibility of conducting a future randomized controlled trial evaluating different approaches to acute post-amputation pain management in patients with combat-related lower limb injuries. This prospective non-randomized pilot study will enroll 36 adult patients undergoing lower limb amputation or reamputation following combat-related trauma. Participants will be allocated to one of three groups according to clinical indications and multidisciplinary team decision: continuous peripheral nerve blocks, preoperative cryoablation, or standard multimodal analgesia. The primary outcomes will assess study feasibility, including recruitment rate, study completion rate, protocol adherence, and completeness of data collection. Secondary outcomes will include pain intensity assessed using the Numeric Rating Scale (NRS), opioid consumption expressed as Morphine Milligram Equivalents (MME), early mobility assessed using the Basic Amputee Mobility Score (BAMS), time to first standing and ambulation, and treatment-related complications. Participants will be followed for 7 days after surgery, with an additional assessment at 1 month.
Detailed description
Combat-related lower limb injuries remain a major cause of limb loss among military personnel. Acute post-amputation pain is highly prevalent following amputation or reamputation procedures and represents a significant barrier to recovery. Inadequate pain control may lead to increased opioid consumption, delayed mobilization, prolonged hospitalization, and impaired participation in rehabilitation programs. Multimodal analgesia remains the standard approach to postoperative pain management; however, opioid requirements often remain substantial despite the use of non-opioid analgesics and adjuvant medications. Regional anesthesia techniques, including continuous peripheral nerve blocks, have demonstrated the potential to improve pain control while reducing opioid exposure. Similarly, cryoablation of peripheral nerves has emerged as a promising technique for prolonged analgesia through reversible interruption of nerve conduction. Despite growing interest in these interventions, evidence regarding their feasibility, safety, and clinical utility in patients with combat-related amputations remains limited. Furthermore, direct comparisons between continuous peripheral nerve blocks, cryoablation, and standard multimodal analgesia in military trauma populations are scarce. The present pilot study is designed to evaluate the feasibility of conducting a future randomized controlled trial investigating different approaches to acute post-amputation pain management. Feasibility outcomes will include recruitment rate, study completion rate, protocol adherence, and completeness of data collection. Secondary objectives include preliminary assessment of pain intensity, opioid consumption, early mobility, and treatment-related complications. The results of this pilot study will provide essential information for the design, sample size calculation, and implementation of a future adequately powered randomized controlled trial. Feasibility criteria for progression to a future randomized controlled trial will be considered achieved if: * Recruitment rate ≥70% * Study completion rate ≥80% * Protocol adherence ≥80% * Missing data \<10% * Serious intervention-related adverse events \<10%
Interventions
PROCEDUREContinuous Peripheral Nerve Blocks
Ultrasound-guided continuous peripheral nerve blocks consisting of a sciatic nerve catheter and a suprainguinal fascia iliaca compartment (SIFI) catheter. Analgesia is provided using 0.25% bupivacaine administered as intermittent boluses according to clinical need.
PROCEDUREPeripheral Nerve Cryoablation
Ultrasound-guided preoperative cryoablation of peripheral nerves selected according to the level of lower limb amputation using the CRYO-S® Painless system.
Standard multimodal analgesia including acetaminophen, non-steroidal anti-inflammatory drugs, pregabalin, optional amitriptyline, and opioid analgesics as needed according to local clinical practice.
Sponsors
Kharkiv National Medical University
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
1. Age 18 to 60 years. 2. Planned or completed lower limb amputation or reamputation due to combat-related trauma. 3. Enrollment before amputation/reamputation or within 24 hours after surgery. 4. Planned or completed lower limb amputation or reamputation requiring postoperative analgesic treatment. 5. Ability to provide written informed consent.
Exclusion criteria
1. Refusal to participate in the study. 2. Inability to provide informed consent. 3. Allergy or hypersensitivity to amide local anesthetics. 4. Infection at the planned site of regional anesthesia or catheter placement. 5. Severe cognitive impairment or psychiatric disorders preventing reliable pain assessment. 6. Decompensated cardiovascular, respiratory, renal, hepatic, or endocrine disease that may affect study outcomes.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Recruitment Rate | 4 months | Proportion of eligible patients successfully enrolled in the study. |
| Study Completion Rate | 1 month | Proportion of enrolled participants who complete the 7-day follow-up and 1-month assessment. |
| Completeness of Data Collection | 1 month | Proportion of completed data points for pain, mobility, opioid consumption, and safety assessments. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain Intensity at Rest (NRS) | Baseline, 24 hours, 48 hours, 72 hours, Day 7, Month 1 | Pain Intensity at Rest measured using the Numeric Rating Scale (NRS). Scores range from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate worse pain intensity. |
| Pain Intensity During Movement (NRS) | Baseline, 24 hours, 48 hours, 72 hours, Day 7, Month 1 | Pain Intensity During Movement measured using the Numeric Rating Scale (NRS). Scores range from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate worse pain intensity. |
| Early Mobility (BAMS) | 24 hours, 72 hours, Day 7, Month 1 | Early mobility will be assessed using the Basic Amputee Mobility Score (BAMS). BAMS is a clinician-administered functional mobility scale that evaluates basic mobility following lower limb amputation. The total score ranges from 0 to 8, with higher scores indicating better mobility performance. |
| Opioid Consumption (MME) | 24 hours, 48 hours, 72 hours, Day 7 | Total opioid consumption expressed as Morphine Milligram Equivalents (MME) during each assessment interval. Higher values indicate greater opioid consumption. |
| Time to First Standing | Up to 7 days | — |
| Treatment-Related Complications | Up to 1 month | — |
Countries
Ukraine
Contacts
CONTACTAndrii Halushko
Outcome results
None listed