The application of human reliability analysis to carpal tunnel decompression

INTRODUCTION

Many surgical procedures are prone to human error, particularly in the learning phase of skills acquisition. Task standardisation has been suggested as an approach to reducing errors, but it fails to account for the human factors associated with learning. Human reliability analysis (HRA) is a structured approach to assess human error during surgery. This study used HRA methodologies to examine skills acquisition associated with carpal tunnel decompression.

METHODS

The individual steps or subtasks required to complete a carpal tunnel decompression were identified using hierarchical task analysis (HTA). The systematic human error reduction and prediction approach (SHERPA) was carried out by consensus of subject matter experts. This identified the potential human errors at each subgoal, the level of risk associated with each task and how these potential errors could be prevented.

RESULTS

Carpal tunnel decompression was broken down into 46 subtasks, of which 21 (45%) were medium risk and 25 (55%) were low risk. Of the 46 subtasks, 4 (9%) were assigned high probability and 18 (39%) were assigned medium probability. High probability errors (>1/50 cases) included selecting incorrect tourniquet size, failure to infiltrate local anaesthetic in a proximal-to-distal direction and completion of the World Health Organization (WHO) surgical sign-out. Three (6%) of the subtasks were assigned high criticality, which included failure to aspirate before anaesthetic injection, whereas 21 (45%) were assigned medium criticality. Remedial strategies for each potential error were devised.

CONCLUSIONS

The use of HRA techniques provides surgeons with a platform to identify critical steps that are prone to error. This approach may improve surgical training and enhance patient safety.

A Systematic Review of the Outcomes of Carpal Ligament Release in Severe Carpal Tunnel Syndrome

PURPOSE

Indications for surgical treatment of severe carpal tunnel syndrome (CTS) are controversial. The aim of this study was to review the outcomes reported in the literature of carpal tunnel release in patients with severe CTS.

METHODS

A systematic review of the outcomes of carpal tunnel release in patients with severe CTS was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Outcome measures included change in symptoms, sensation (2-point discrimination, light touch), thenar atrophy, strength (power and pinch grip), electrophysiology, median nerve morphology, and patient-reported outcome measures. Outcomes are reported by ranges of the percentage of patients/hands improved in the included studies.

RESULTS

Thirty-eight papers were selected, representing 2,531 patients and 2,712 hands. Demographic information on age and sex were available for a total of 1,542 patients. Mean age ranged from 49.8 to 83 years and 72% were female. All studies that assessed patient-reported outcome measures before and after surgery reported significant improvements. Complete resolution of paresthesia occurred in 55%-98% of hands across different studies. Resolution of numbness occurred in between 39% and 94% of hands. Pain completely resolved in 64%-100% and weakness in 60%-75% of hands. Two-point discrimination and light touch improved postoperatively. Power grip, key, tripod, index-thumb pulp pinch, and thumb opposition increased. Motor and sensory amplitudes, distal motor latencies, and sensory conduction velocities improved. Patient-reported outcomes indicated symptomatic improvement and reduced disability.

CONCLUSIONS

Symptomatic improvement following carpal tunnel release in patients with severe CTS can occur. Patients should be counseled about the unpredictability of the outcomes and factors that might affect outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Comorbid status influences quality of life following carpal tunnel decompression

The aim of this study was to characterize the change in health-related quality of life following carpal tunnel decompression. Pre- and postoperative Euroqol 5 Dimensions scores were collected prospectively over three years. Outcomes were available for 435 of 563 patients (77%); mean age was 62 years. Comorbid status was described using the Charlson Comorbidity Index. Change in Euroqol 5 Dimensions scores declined with increasing age and Charlson Comorbidity Index: the greatest improvement in quality of life occurred in the youngest group (+0.07 vs. -0.07 in the oldest group; p < 0.001) and patients with the lowest Comorbidity Index (+0.05 vs. -0.07 in the highest comorbidity group; p < 0.001). Charlson Comorbidity Index was an independent predictor of worse change in Euroqol 5 Dimensions scores on regression analysis. Carpal tunnel decompression results in significant improvement in health-related quality of life in younger patients with minimal comorbidities, but not in older patients with more comorbidities. We advise interpreting the Euroqol 5 Dimensions scores with caution in this patient cohort. LEVEL OF EVIDENCE: III (cohort study).

The relationship of mental health status to functional outcome and satisfaction after carpal tunnel release

We studied whether mental health status is significantly correlated to patient reported functional outcomes and satisfaction after carpal tunnel release. Over a 7-year period, 809 patients completed Short Form-12 (SF-12) questionnaires which allowed calculation of the SF-12 mental component summary 1 year postoperatively, 780 (96%) completed a satisfaction questionnaire and 777 (96%) completed a QuickDisabilities of the Arm, Shoulder, and Hand (DASH) questionnaire. Median QuickDASH score was 55 preoperatively (interquartile range [IQR] 28) and 14 postoperatively (IQR 32). A total of 674 patients were satisfied. Patients with mental disability had worse QuickDASH scores (median 34, IQR 41) and a higher incidence of dissatisfaction (52/245, 21%) than those without mental disability (n = 9, IQR 20, 10%, both p < 0.001). Regression analyses indicated scores in the SF-12 mental component summary were significantly related to postoperative QuickDASH score (p < 0.001) and satisfaction (p = 0.02). We concluded that patients with mental disability report poorer outcomes and lower satisfaction rates; however, the majority still exhibit significant improvements and are satisfied. Level of evidence: II.

Carpal tunnel decompression in primary care: what is the infection risk and is it safe and effective?

INTRODUCTION

The demand for elective hand surgery in England is predicted to double by 2030 compared with 2011. With such increase in demand, the UK must seek strategies to reduce costs of treatment while still maintaining standards of care. Carpal tunnel decompression performed in a treatment room rather than in theatre may provide a safe alternative setting. As yet, there are no UK-based studies that identify the risk of infection following surgery performed in a treatment room and there are no studies whatsoever assessing the qualitative outcomes of patients undergoing hand surgery outside a theatre environment. Our aim was to assess whether carpal tunnel decompression performed in the community is safe, in terms of infection risk, and effective.

MATERIALS AND METHODS

Patient outcome measures were prospectively recorded following carpal tunnel decompression in one single primary care centre performed by one surgeon from 2012 to 2017. Infection following surgery was evaluated for retrospectively.

RESULTS

A total of 460 patients underwent carpal tunnel decompression within the study time period. There were three superficial infections identified, giving an infection rate of 0.65%. There were no deep infections identified. There was a statistically significant improvement in both symptom and functional outcomes following surgery, with results comparable to other studies where surgery was performed in theatre.

DISCUSSION

We believe that carpal tunnel decompressions performed in a treatment room is both safe, in terms of infection risk, and effective. Surgeons should consider this location as an alternative setting to the main operating theatre.

The Net Promoter Scores with Friends and Family Test after four hand surgery procedures

The Friends and Family Test, a variant of the Net Promoter Score, was adapted for the National Health Service to evaluate overall patient satisfaction and how likely patients are to recommend an intervention. It ranges from -100 to 100. Positive scores indicate good performance. This study quantifies the scores in 810 patients at a mean of 14 months following four common procedures. The score was 83 for trigger finger release ( n = 103), 68 for carpal tunnel decompression ( n = 467), 62 for surgery for Dupuytren's disease ( n = 224) and 44 for ganglia excision ( n = 16). Our study indicates that these procedures are highly valued and are recommended by patients according to the Friends and Family Test. The results of the Friends and Family Test correlated well with postoperative functional improvement and satisfaction. We conclude from this study that a compound score based on the Friends and Family Test is a useful addition to traditional measures of patient satisfaction. Level of evidence: II.

Tendencies in the Post-surgical Approach for Carpal Tunnel Syndrome. Current Clinical Practice

BACKGROUND AND OBJECTIVES

Evidence and specific interventions after carpal tunnel release are limited. The main purpose of this study was to elucidate the current practice patterns of professionals from around the world after carpal tunnel release.

MATERIAL AND METHODS

A 15-item English survey was designed and distributed via email and through social networks to professionals from different countries. A descriptive study of the items was carried out comparing them with the published evidence.

RESULTS

In our study, we identified a great variety in the post-surgical approach of carpal tunnel syndrome in 23 different countries.

DISCUSSION AND CONCLUSIONS

There are no common criteria in the techniques used after surgical decompression of the median nerve.

Pain and outcomes of carpal tunnel release under local anaesthetic with or without a tourniquet: a randomized controlled trial

We conducted a prospective randomized controlled trial to investigate carpal tunnel decompression under local anaesthesia. Carpal tunnel decompression was performed in 37 wrists using local anaesthesia and an arm tourniquet and 36 without tourniquet but with a local anaesthetic mixture containing adrenaline. Patients who underwent carpal tunnel decompression using a tourniquet experienced a significantly greater degree of pain when compared with those who did not have a tourniquet. Pain and hand function improved to a similar degree in both groups. We conclude that carpal tunnel decompression performed with a tourniquet causes patients unnecessary pain with no additional benefit as compared with the wide-awake carpal tunnel decompression without use of a tourniquet.

LEVEL OF EVIDENCE

I.

Incidental finding of a persistent median artery (palmar type) during a routine carpal tunnel decompression: a case report

Carpal tunnel syndrome is characterised by compression of the median nerve. The mainstay of treatment is surgical decompression. This case report highlights the occurrence of a persistent median artery, which could complicate surgery. A 55-year-old woman underwent carpal tunnel decompression. An incidental finding of a large-calibre persistent median artery, which was superficial to the flexor sheath, could have been damaged. This was carefully retracted and the procedure was completed, without any complications. Several studies have shown the prevalence of persistent median artery to range from 1.1-27.1%. It is usually found deep to the flexor retinaculum but in this case it was found to be just beneath the palmar fascia. There is increased chance of iatrogenic injury with this particular variant. Surgeons performing the procedure should be mindful of this variation, because accidental damage could result in devastating consequences to the hand.

Injection versus Decompression for Carpal Tunnel Syndrome-Pilot trial (INDICATE-P)-protocol for a randomised feasibility study

Background

Carpal tunnel syndrome (CTS) is the commonest peripheral nerve disorder in the UK, with over 52,996 carpal tunnel decompressions performed in 2011. By 2030, this figure is estimated to double. Whilst evidence supports conservative measures for mild symptoms, and early surgery for severe symptoms, controversy remains over the most appropriate management for patients that present with moderate disease, with regard to early surgery or late surgery following steroid injection. Injection versus Decompression for Carpal Tunnel Syndrome-Pilot trial (INDICATE-P) is a feasibility study for a multicentre, randomised controlled trial (INDICATE) to determine whether patients over the age of 18 with moderate CTS should undergo early surgical decompression of the median nerve or a single steroid injection (followed by later surgery if required).

Methods/design

INDICATE-P is a feasibility study for an open (non-blinded) randomised controlled pilot trial. Eligible participants will be adults with a clinical diagnosis of moderate CTS. This is defined as symptoms disturbing sleep or restricting activities of daily living or work, despite a 2-week trial of night splints. Participants will be randomised to one of two possible interventions: surgical decompression or a single steroid injection (followed by surgery later if required). Clinical outcome measures will be captured by postal questionnaire at 1, 3, 6 and 12 months post-randomisation. In order to improve the study design for the main INDICATE trial, feasibility data will also be collected to identify difficulties in recruitment and retention, to gain patient feedback on questionnaires and to confirm the suitability of the proposed outcome measures.

Discussion

The INDICATE-P feasibility study will contribute to the design and execution of the INDICATE trial, which will seek to assess the safety and effectiveness of two approaches to treatment for patients over 18 years of age with moderate CTS: early carpal tunnel decompression or a single steroid injection (followed by later surgery).

Arm versus forearm tourniquet for carpal tunnel decompression - Which is better? A randomized controlled trial

Tourniquet pain is a common source of complaint for patients undergoing carpal tunnel decompression and practice varies as to the tourniquet position used. There is little evidence to suggest benefit of one position over another. Our aim was to compare patient and surgeon experience of forearm and arm tourniquets. Following a power calculation, 100 patients undergoing open carpal tunnel decompression under local anaesthetic were randomized to either an arm or a forearm tourniquet. Measurements of blood pressure, heart rate and pain were taken at 2.5 min intervals. The operating surgeon also provided a visual analogue scale rating for the extent of bloodless field achieved and for any obstruction caused by the tourniquet. There was no statistically significant inter-group difference in patient pain or physiological response, tourniquet time, bloodless field or length of procedure. The degree of obstruction caused by the tourniquet was significantly higher in the forearm group.

LEVEL OF EVIDENCE

I. Prospective Randomized Controlled Trial.

Pictorial essay: Role of ultrasound in failed carpal tunnel decompression

USG has been used for the diagnosis of carpal tunnel syndrome. Scarring and incomplete decompression are the main causes for persistence or recurrence of symptoms. We performed a retrospective study to assess the role of ultrasound in failed carpal tunnel decompression. Of 422 USG studies of the wrist performed at our center over the last 5 years, 14 were for failed carpal tunnel decompression. Scarring was noted in three patients, incomplete decompression in two patients, synovitis in one patient, and an anomalous muscle belly in one patient. No abnormality was detected in seven patients. We present a pictorial review of USG findings in failed carpal tunnel decompression.