Sensory Distribution of Lateral Femoral Cutaneous Nerve Block - A Randomized, Blinded, Paired Trial in Healthy Volunteers
Trial Snapshot
- Phase
- Phase 4
- Status
- Completed
- Sponsor
- Zealand University Hospital
- Enrollment
- 20
- Locations
- 1
- Primary Endpoint
- Difference in the percentage coverage of the incision (posterior approach) assessed by cold sensation
Study Overview
Brief Summary
The purpose of this study is to investigate and describe the anatomical distribution of the sensory outcome following LFCN block (LFCN = lateral femoral cutaneous nerve) in relation to the incisional lines after Total Hip Arthroplasty (THA). Furthermore, is the aim to examine whether there is a motorial outcome corresponding to the Femoral nerve. The trial will be conducted in healthy volunteers in a blinded, randomized paired study.
Detailed Description
Background:
Total hip arthroplasties may be associated with moderate to intense postoperative pain. It is essential that pain treatment, besides being analgesic, has a minimum of side effects, especially those opioid-related, in order to achieve low morbidity, high patient satisfaction and to encourage the functional rehabilitation.
Currently, there is no "gold standard" for pain treatment after THA, and there exists a large variety of treatment options. Some patients who have undergone THA, can be difficult to sufficiently treat with conventional analgesics without reaching additional morphine doses where side effects are unacceptable. It is therefore important to explore other treatment options, including nerve blockade.
Nerve blocks have previously been used after THA operations, but have been hampered by the fact, that the nerve blocks have an effect on the motorial nerve, inhibiting early mobilization and possibly increasing tendencies to fall when mobilized. LFCN is purely sensorial and can therefore relieve the patient of pain without influencing the early mobilization. In addition, the application of nerve blocks is very easy and virtually without complications.
In two previous trials, the investigators have studied the effect of LFCN blocks in pain treatment after THA. In the recent study, the LFCN block was applied in patients after THA, who still had visual analogue scale (VAS) mobilization pain > 40 mm when lifting their leg stretched. The LFCN block alleviated significantly the average pain at group level. Meanwhile 42% of patients in the study had no or limited effect of the block. The reason for this may be due to the fact, that LFCN block does not cover all types of pain after THA, but also the fact, that the nerve innervation area has individual differences in the anatomical distribution. It is therefore relevant to describe the anatomical distribution of a LFCN block in order to determine whether the variations in anatomy is a contributing factor of the high number of patients with no effect of the blockade.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Treatment
- Masking
- Triple (Participant, Investigator, Outcomes Assessor)
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Participants who have given their written consent after understanding the content and limitations og the study.
- •BMI ≥18 and ≤ 30
Exclusion Criteria
- •Participants who can not cooperate in the study.
- •Participant who can not speak or understand danish.
- •Allergies to the drugs used in the study.
- •Alcohol consumption that exceeds 21 units per week.
- •Drug abuse by the investigators judgement.
- •Daily consumption of prescription required analgesic drugs within the last four weeks.
- •Consumption of over the counter analgesic drugs within the last 48 hours.
- •Neuromuscular defects, former surgery or trauma to the lower extremities.
- •Diabetes mellitus.
- •Pregnant women (women in the fertile age must have used safe contraception and test negative with a urine-HCG to be able to participate in the study).
Arms & Interventions
Treatment A
Injection around the lateral femoral cutaneous nerve:
8 ml Ropivacaine 0.75 %.
Intervention: Ropivacaine (Drug)
Treatment B
Injection around the lateral femoral cutaneous nerve:
8 ml isotonic Saline.
Intervention: Isotonic Saline (Drug)
Outcomes
Primary Outcomes
Difference in the percentage coverage of the incision (posterior approach) assessed by cold sensation
Time Frame: 1 hour post-block
Difference in the percentage coverage of the incision (posterior approach) between the side given Ropivacaine versus the side given saline assessed by cold sensation with alcohol soaked gauze.
Secondary Outcomes
- Difference in the percentage coverage of the incision (anterior-lateral approach) assessed by cold sensation(1 hour post-block)
- Difference in the percentage coverage of the incision (posterior approach) assessed by pin-prick(1 hour post-block)
- Difference in the percentage coverage of the incision (anterior-lateral approach) assessed by pin-prick(1 hour post-block)
- The percentage of participants with no sensory function (VAS = 0) assessed by Maximum pain during tonic heat stimulation test on the most superior part of the incision (posterior approach)(1 hour post-block)
- The percentage of participants with no sensory function (VAS = 0) assessed by Maximum pain during tonic heat stimulation test on the most inferior part of the incision (posterior approach)(1 hour post-block)
- The percentage of participants with no sensory function (VAS = 0) assessed by Maximum pain during tonic heat stimulation test on the most superior part of the incision (anterior-lateral approach)(1 hour post-block)
- The percentage of participants with no sensory function (VAS = 0) assessed by Maximum pain during tonic heat stimulation test on the most inferior part of the incision (anterior-lateral approach)(1 hour post-block)
- The percentage of participants with no sensory function (no pain detection) assessed by Heat pain detection threshold test on the most superior part of the incision (posterior approach)(1 hour post-block)
- The percentage of participants with no sensory function (no pain detection) assessed by Heat pain detection threshold test on the most inferior part of the incision (posterior approach)(1 hour post-block)
- The percentage of participants with no sensory function assessed (no pain detection) by Heat pain detection threshold test on the most superior part of the incision (anterior-lateral approach)(1 hour post-block)
- The percentage of participants with no sensory function (no pain detection) assessed by Heat pain detection threshold test on the most inferior part of the incision (anterior-lateral approach)(1 hour post-block)
- Estimation of the area with sensory loss assessed by cold sensation(1 hour post-block)
- Estimation of the area with sensory loss assessed by pin-prick(1 hour post-block)
- The difference in MVIC (maximal voluntary isometric contraction) of the leg(1 hour post-block)