The Evaluation of Post-Surgical Scar Hypersensitivity in the Hand
Research type
Research Study
Full title
The Evaluation of Post-Surgical Scar Hypersensitivity in the Hand (the ESCHER Study)
IRAS ID
246734
Contact name
Donna L. Kennedy
Contact email
Sponsor organisation
Imperial College London and Imperial College Healthcare NHS Trust
Duration of Study in the UK
1 years, 11 months, 30 days
Research summary
Summary of Research
TITLE
The Evaluation of Post-Surgical Scar Hypersensitivity in the Hand (ESCHER Study)BACKGROUND
Following planned hand surgery, some patients may have an extremely sensitive or hypersensitive surgical scar. Scar hypersensitivity interferes with normal use of the hand in everyday activity and this can last for up to 2 years after surgery. At present, there is not an accepted method for diagnosing a “hypersensitive scar”. Furthermore, there is no standardised method for measuring the severity of scar hypersensitivity or change in scar sensitivity over time or following treatment. Although physical characteristics of scar such as scar thickness or texture are thought to be related to hypersensitivity this has not been proven. It is not clear how a hypersensitive scar differs physically from a normal or non-hypersensitive scar. Treatment for scar hypersensitivity commonly includes scar massage and desensitization techniques such as pressure and vibration however there is very limited evidence these techniques are effective. It is important to develop a standardised method for measuring scar hypersensitivity including the physical aspects of scar and how scars interfere with daily function. A standardised scar hypersensitivity assessment will help us to evaluate hand surgery scar outcomes and to determine what scar treatments are most beneficial for patients.
DESIGN: Longitudinal, non-interventional repeated measures observational studyAIMS: investigate the association of objective and subjective measures of scar outcome including physical characteristics, pain and function with patient-reported scar hypersensitivity in elective hand surgery patients.
DURATION: 24 months
NUMBER of SUBJECTS: 35
OUTCOME MEASURES
Primary outcome measure: Scar Pain & Interference Scale
Secondary outcome measures:
Scar physical characteristics
Hand sensation and strength
Patient-rated scar appearance and interference, hand function and painPOPULATION
Adults who have undergone unilateral elective surgery to the hand or wrist.Summary of Results
The evaluation of hand scars is not standardised and there is no “gold standard” assessment tool. The ESCHER study investigated the relationship of objective measures of hand scar outcome including physical characteristics, sensory function and hand functional ability with patient-reported scar hypersensitivity in elective hand surgery patients with the aim of supporting best clinical practice.
Methods:
ESCHER is a longitudinal repeated-measures observational study. The study was conducted in accordance with the 18th World Medical Assembly, Helsinki 1964 and later revisions. Study ethics approval was received from HRA and Health and Care Research Wales (HCRW) on 20th December 2018 (18/LO/2161). The current Trust pathways for management of patient referral, evaluation, surgery and post-operative care were continued during the trial. The ESCHER study team included two patient-collaborators. Patient-collaborators reviewed all study testing measures, questionnaires and patient-related study documentation (participant information sheet, consent form and study poster) and provided feedback regarding acceptability of study measures and clarity and transparency of all study documentation.
Participants
Number of subjects: 35
Type of subjects: Adults over the age of 18 who have undergone elective orthopaedic or plastic surgery to one hand or wrist Procedure Participants attended two assessment sessions conducted in the Therapy Department, Charing Cross Hospital, London United Kingdom. Initial assessments were completed between 2- and 4-weeks post- surgery; the second assessment between 3- and 4-months post-surgery. Clinician completed measures included demographics and medical history, evaluation of scar physical characteristics including thickness and colour (Observer Scar Assessment Scale (POSAS) (Draaijers LJ et al., 2004), scar temperature, pliability and sensory function (Rolke et al 2006). Standardised, validated patient completed measures included the Palmar Pain Scale (PPS) (Itroshi, I 2011) (primary outcome measure), Patient Scar Assessment Questionnaire (PSAQ) (Durani, P et al., 2009), Michigan Hand Outcomes Questionnaire (MHQ) (Chung K et al 1998); Neuropathic Pain Symptom Inventory NPSI) (Bouhassira, D 2004); Modified STarT Back tool (Hill JC et al 2008) and numerical pain ratings scales.Results: The ESCHER study was due to close on 31st December 2020 but was suspended to recruitment on the 1st of April 2020 due to COVID-19, in keeping with national guidance. Due to the persistence of the pandemic and secondary suspension of planned, non-urgent hand surgery, the ESCHER study was not reopened to recruitment. Twenty-one participants provided informed consent and were included. Two participants dropped out after the initial assessment (one moved away and one became medically unwell). Due to premature study closure, only 13 participants completed 4 month study assessments. Participant median age was 62 years (27-85); 16 (75%) were female. Participants underwent hand surgery including carpal tunnel release (12 [57%]; trigger finger release (3 [14%]) and trapeziectomy (2 [10%]). Wound closure was with prolene (non-absorbable) in 18 (86%) participants; sutures were removed at a mean of days 13.44 (sd 2.2). Surgery was on the dominant hand in 14 (67%) participants. Days to baseline assessment mean 32.6 (sd 14.38); days to follow up assessment 132.15 (sd 18.54). At one month post-surgery, participant rated scar pain on the PPS was none 24%; very mild 19%; mild 29%; moderate 24% and severe 5%. Scar pain was reduced at 4 months with 77% reporting no pain; 8% very mild pain; 8% mild pain and 8% moderate pain. Baseline modified StarT Back total score correlated with PPS (r=.437, p=0.04) and patient reported scar interference (r = .708, p< .001). Patient Scar Assessment Questionnaire (PSAQ) scores for satisfaction with symptoms and scar pain were associated with PPS (r = .760, p< 0.001). On the patient-completed Neuropathic Pain Symptom Inventory the most commonly reported scar symptom was stabbing and this was correlated with the PPS (r= .514, p=0.017). Pressure was the most commonly reported evocative stimuli, and was correlated with the PPS (r =.638, p= 0.002). Participants did not report symptoms consistent with mechanical allodynia. At one month post surgery, participants demonstrated scar mechanical pain sensitivity as tested with pin-prick stimulators; this resolved at 4 months and was not correlated with reported scar pain. At 4 months, participants demonstrated thermal hyperalgesia at the scar, with increased cold pain sensitivity (unaffected hand cold pain detection threshold 7.2 degrees C; scar 24.1 degrees C). The clinician completed Observer Scar Assessment Scale was not correlated with patient reported scar pain (p = 0.74), nor was scar pliability, as measured with tonometry (r =-0.138, p=0.551).
Conclusion: Our findings suggest that patient reported scar pain in the hand and wrist is consistent with hyperaesthesia – an increased sensitivity to stimulation, including touch and thermal stimuli, with OR without pain. Patients demonstrate increased mechanical pain sensitivity and cold hyperalgesia but do not demonstrate dynamic mechanical allodynia. Importantly, clinician evaluated scar morphology and pliability were not associated with patient reported scar pain. This early work would benefit from validation in a larger sample of participants.
REC name
London - Harrow Research Ethics Committee
REC reference
18/LO/2161
Date of REC Opinion
19 Dec 2018
REC opinion
Favourable Opinion