Avoiding Iatrogenic Nerve Injury in Endoscopic Carpal Tunnel Release

Aesthetic and Functional Outcomes of Open Carpal Tunnel Release and Thread Carpal Tunnel Release: A Randomized Clinical Trial

Background and Objectives  Surgical techniques for carpal tunnel release (CTR) have gradually become less invasive. No substantial evidence supports replacing the open carpal tunnel release (OCTR) with novel minimally invasive approaches. Thread carpal tunnel release (TCTR) is a new minimally invasive CTR method associated with promising results. This study aimed to compare the aesthetic and functional outcomes of OCTR with TCTR. Materials and Methods  This study was a randomized clinical trial conducted in a hospital in Tehran, Iran, in 2022. Patients were randomized to OCTR and TCTR groups through simple randomization. Data such as demographics, nerve conduction study, electromyography, pain, and sensory evaluation by monofilament test were recorded in patients at baseline and after 3 months. Aesthetic evaluation was conducted by assessing the scar length and patients' satisfaction 3 months after the surgery. Results  Twenty patients (10 in each group) entered the final analysis. Nerve conduction study, electromyography, and sensory evaluation were similar between groups 3 months after the operation. The TCTR group had lower postsurgical pain ( p  < 0.001) and lower scar length ( p  < 0.001) compared to the OCTR group. Overall satisfaction was not statistically different between TCTR and OCTR. Conclusion  The TCTR method is safe in patients with CTS, and its efficacy is similar to OCTR. It can be a good alternative for OCTR, with a better aesthetic outcome.

Causes of Iatrogenic Median Nerve Injury after Endoscopic Carpal Tunnel Release

Background: Endoscopic carpal tunnel release (ECTR) is a less invasive procedure but has a higher risk of complications. We analysed ECTR cases dividing them into three periods according to a single surgeon's experience when the ECTR was performed: the initial, midterm and late period. Cases of iatrogenically induced median nerve injuries that occurred after ECTR were then noted and evaluated. Methods: We reviewed 195 ECTRs done with the 2-portal technique and divided the patients into three groups according to periods of when ECTR was done. The indications for ECTR surgery were limited to severe CTS cases. These groups of patients were similar in terms of age, duration of disease, electrophysiological study results and severity of the disease. The patients were evaluated for median neuropathy pre- and postoperatively using Semmes-Weinstein monofilament test (SWT), Disabilities of the arm, shoulder and hand (DASH) Score, Coin-flip test (CFT), postoperative paraesthesias and complications, such as pillar pain, and so on. Electrophysiological evaluation was performed only preoperatively. Results: Postoperative median nerve recovery was overall good. Normal recovery was noted in 181 cases (93%). SWT, DASH and CFT were all significantly improved upon follow-up in all three groups. In terms of iatrogenic neuropathy, median nerve palsy worsened (including those transiently worsened) after ECTR in 11 cases (5.6%), even in the later period. The sensory disturbance was equally worsening from the radial to the ulnar side. Conclusions: The fact that there were neurologically worsened cases even in the later period, when the operator is higher skilled in the technique, suggests that the surgical technique itself may be the one posing higher risk than the level of surgical skill. The most likely causes of aggravated nerve palsy were a direct injury by cannula insertion at the proximal portal, or additional median nerve compression during cannula insertion into the carpal tunnel. Level of Evidence: Level IV (Therapeutic).

Iatrogenic Nerve Injuries of the Upper Extremity: A Critical Analysis Review

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Iatrogenic nerve injuries may occur after any intervention of the upper extremity.

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Causes of iatrogenic nerve lesions include direct sharp or thermal injury, retraction, compression from implants or compartment syndrome, injection, patient positioning, radiation, and cast/splint application, among others.

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Optimal treatment of iatrogenic peripheral nerve lesions relies on early and accurate diagnosis.

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Advanced imaging modalities (e.g., ultrasound and magnetic resonance imaging) and electrodiagnostic studies aid and assist in preoperative planning.

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Optimal treatment of iatrogenic injuries is situation-dependent and depends on the feasibility of direct repair, grafting, and functional transfers.

Our 15-year experience of complications of Chow's technique for endoscopic carpal tunnel releasing

PURPOSE

Our objective in this study was to summarize our 15-year experience treating carpal tunnel syndrome released with Chow technique, focusing on the complications and how to avoid them.

METHOD

We systematically evaluated the postoperative complications in 211 patients who underwent endoscopic carpal tunnel release (ECTR) with Chow technique. We recorded the incidence of complex regional pain syndrome type I (CRPS I), median nerve and digital nerve injury, superficial palmar arch injury, and tendon injury.

RESULT

The overall incidence of complications was 5.6%, and involved 10 cases of CRPS I, 1 case of median nerve trunk injury, and 1 case of superficial palmar arch injury. No other complication occurred. We used oral pregabalin and neurotropin to relieve CRPS I symptoms, and performed second operations for the other two complications.

CONCLUSIONS

Our study revealed that ECTR could reduce structural and cutaneous complications, but increase the incidence of nerve injury. we speculated that the incidence of CRPS I may be higher in the Asian population.

Effectiveness and safety of surgical treatment of carpal tunnel syndrome via a mini-transverse incision and a bush hook versus a mid-palmar small longitudinal incision

Background

Minimally invasive surgery for carpal tunnel syndrome has been consistently the mainstay of treatment. In this study, we developed a novel bush hook via a mini-transverse incision at proximal wrist crease to surgically treat carpal tunnel syndrome and our aim was to compare the results with those of mid-palmar small longitudinal incision in carpal tunnel release.

Methods

This is a retrospective study on patients who received a mini-transverse incision and a novel bush hook or a mid-palmar small longitudinal incision for treatment of carpal tunnel syndrome. The decision to receive either technique was made mainly based on patients' choice. The clinical results were evaluated at 1 week, 1 month, 3 and 6 months postoperatively and compared.

Results

In total, 58 patients in mini-transverse incision group and 74 in mid-palmar longitudinal incision group were include. The follow-up period was 6.8 ± 1.6 months. The mini-transverse incision group had a significantly smaller incision (4.3 ± 0.4 mm vs. 26.2 ± 1.6 mm), shorter surgical time (7.8 ± 2.6 min vs. 19.7 ± 2.8 min), but not for hospital stay (3.2 ± 1.9 vs. 3.6 ± 2.2 days). Both groups showed significant improvement from baseline level at any time points postoperatively (all P < 0.001). At 1 month and 3 months, the mini-transverse incision group showed a significantly better improvement of VAS, SSS and FSS score (P < 0.05). At 6 months, the differences were no longer significant (P > 0.05). In addition, the mini-transverse incision group showed a significantly reduced time to return to the work and activities, tendency to higher rate of excellence and good outcomes and fewer complications.

Conclusions

This novel technique via a mini-transverse incision and bush hook showed better clinical effectiveness and safety, and can be considered as an alternative for wrist tunnel release after the results are validated by higher-level evidence studies.

Evidence level: III.

Iatrogenic nerve injuries: a potentially serious medical and medicolegal problem. About a series of 42 patients and review of the literature

OBJECTIVE

To analyze the management of iatrogenic nerve injuries (iNI) in 42 patients.

METHODS

Retrospective analysis of the charts.

RESULTS

The iNI occurred mostly during a surgical procedure (n = 39), either on a nerve or plexus (n = 13), on bone, joint, vessel or soft tissue (n = 24) or because of malpositioning (n = 2). The most commonly injured nerves were the brachial plexus, radial, sciatic, femoral, or peroneal nerves. 42.9% of the patients were referred later than 6 months. A neurological deficit was present in 37 patients and neuropathic pain in 17. Two patients were lost to follow-up. Conservative treatment was applied in 23 patients because of good spontaneous recovery or compensation or because of expected bad prognosis whatever the treatment. Surgical treatment was performed in 17 patients because of known nerve section (n = 2), persistent neurological deficit (n = 12) or invalidating neuropathic pain (n = 3); nerve reconstruction with grafts (n = 8) and neurolysis (n = 8) were the most common procedures. Outcome was satisfactory in 50%. Potential reasons of poor outcome were a very proximal injury, placement of very long grafts, delayed referral and predominance of neuropathic pain. According to the literature delayed referral of iNI for treatment is frequent. We provide an illustrative case of a young girl operated on at 6.5 months for femoral nerve reconstruction with grafts while nerve section was obvious from the operative note and pathological tissue analysis. Litigation claims (n = 10) resulted in malpractice (n = 2) or therapeutic alea (n = 5) (3 unavailable conclusions). i CONCLUSIONS: NI can result in considerable disability, pain and litigation. Optimal management is required.

Neurologic complications in common wrist and hand surgical procedures

Nerve dysfunction after upper extremity orthopedic surgery is a recognized complication, and may result from a variety of different causes. Hand and wrist surgery require incisions and retraction that necessarily border on small peripheral nerves, which may be difficult to identify and protect with absolute certainty. This article reviews the rates and ranges of reported nerve dysfunction with respect to common surgical interventions for the distal upper extremity, including wrist arthroplasty, wrist arthrodesis, wrist arthroscopy, distal radius open reduction and internal fixation, carpal tunnel release, and thumb carpometacarpal surgery. A relatively large range of neurologic complications is reported, however many of the studies cited involve relatively small numbers of patients, and only rarely are neurologic complications included as primary outcome measures. Knowledge of these neurologic outcomes should help the surgeon to better counsel patients with regard to perioperative risk, as well as provide insight into workup and management of any adverse neurologic outcomes that may arise.

Iatrogenic lesions of peripheral nerves

Iatrogenic nerve lesions (INLs) are an integral part of peripheral neurology and require dedicated neurologists to manage them. INLs of peripheral nerves are most frequently caused by surgery, immobilization, injections, radiation, or drugs. Early recognition and diagnosis is important not to delay appropriate therapeutic measures and to improve the outcome. Treatment can be causative or symptomatic, conservative, or surgical. Rehabilitative measures play a key role in the conservative treatment, but the point at which an INL requires surgical intervention should not be missed or delayed. This is why INLs require close multiprofessional monitoring and continuous re-evaluation of the therapeutic effect. With increasing number of surgical interventions and increasing number of drugs applied, it is quite likely that the prevalence of INLs will further increase. To provide an optimal management, more studies about the frequency of the various INLs and studies evaluating therapies need to be conducted. Management of INLs can be particularly improved if those confronted with INLs get state-of-the-art education and advanced training about INLs. Management and outcome of INLs can be further improved if the multiprofessional interplay is optimized and adapted to the needs of the patient, the healthcare system, and those responsible for sustaining medical infrastructure.

Carpal and cubital tunnel and other, rarer nerve compression syndromes

BACKGROUND

Carpal tunnel syndrome is by far the most common peripheral nerve compression syndrome, affecting approximately one in every six adults to a greater or lesser extent. Splitting the flexor retinaculum to treat carpal tunnel syndrome is the second most common specialized surgical procedure in Germany. Cubital tunnel syndrome is rarer by a factor of 13, and the other compression syndromes are rarer still.

METHODS

This review is based on publications retrieved by a selective literature search of PubMed and the Cochrane Library, along with current guidelines and the authors' clinical and scientific experience.

RESULTS

Randomized controlled trials have shown, with a high level of evidence, that the surgical treatment of carpal tunnel syndrome yields very good results regardless of the particular technique used, as long as the diagnosis and the indication for surgery are well established by the electrophysiologic and radiological findings and the operation is properly performed. The success rates of open surgery, and the single-portal and dual-portal endoscopic methods are 91.6%, 93.4% and 92.5%, respectively. When performed by experienced hands, all these procedures have complication rates below 1%. The surgical treatment of cubital tunnel syndrome has a comparably low complication rate, but worse results overall. Neuro-ultrasonography and magnetic resonance imaging (neuro-MRI) are increasingly being used to complement the diagnostic findings of electrophysiologic studies.

CONCLUSION

Evidence-based diagnostic methods and treatment recommendations are now available for the two most common peripheral nerve compression syndromes. Further controlled trials are needed for most of the rarer syndromes, especially the controversial ones.

Perioperative upper extremity peripheral nerve traction injuries

Peripheral nerve traction injuries may occur after surgical care and can involve any of the upper extremity large peripheral nerves. In this review, injuries after shoulder or elbow surgical intervention are discussed. Understanding the varying mechanisms of injury as well as classification is imperative for preoperative risk stratification as well as management.

Technical difficulties and their prediction in 2-portal endoscopic carpal tunnel release for idiopathic carpal tunnel syndrome

PURPOSE

This study aimed to identify technical difficulties encountered during 2-portal endoscopic carpal tunnel release (ECTR) and to determine their incidence. Furthermore, we assessed the possibility of preoperatively predicting such technical difficulties.

METHODS

We retrospectively reviewed the records of 311 hands of 311 patients with idiopathic carpal tunnel syndrome who underwent ECTR with our modified Chow 2-portal technique. Any technical difficulties during the procedure were reviewed and correlated with preoperative physical findings, nerve conduction studies, and magnetic resonance imaging findings, by use of the t test, χ(2) test, and binary regression analysis.

RESULTS

One or more difficulties were encountered in 139 of 311 hands (44.7%), whereas surgery in the remaining 172 hands (55.3%) was performed without any difficulties. Technical difficulties encountered were as follows: tight access in 61 hands, difficulty in identifying the distal part of the transverse carpal ligament through the exit portal in 35 hands, synovial tissue being caught at the cannula tip when pulling it out of the carpal tunnel in 39 hands, steep angle of the cannula assembly with difficulty in emerging from the exit portal in 29 hands, and other difficulties. Postoperative worsening of symptoms was observed in 8 hands (2.6%), in all of which technical difficulties were encountered. Tight access was noted in younger patients and those with a small cross-sectional area at the hook-of-hamate level. The entire ECTR procedure for older female patients was more likely to be easily performed.

CONCLUSIONS

The surgeon may face a variety of technical difficulties during ECTR. Technical difficulties were most often encountered during introduction of the cannula assembly into the carpal tunnel and pulling it out of the exit portal. Older female patients may be the best candidates for 2-portal ECTR.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Outcome prediction value of nerve conduction studies for endoscopic carpal tunnel surgery

OBJECTIVE

Carpal tunnel syndrome is the most common entrapment neuropathy. We explore the clinical use of nerve conduction study in the outcome prediction and preoperative selection for endoscopic carpal tunnel syndrome surgery.

METHODS

Sixty-seven patients with carpal tunnel syndrome were prospectively enrolled. Each patient's clinical symptomatic score at baseline and 3 months postsurgery was compared with nerve conduction study parameters of distal motor latency, motor amplitude, motor conduction velocity, distal sensory latency, sensory amplitude, and sensory conduction velocity. A statistical logistic regression model was used to ascertain outcomes.

RESULTS

Endoscopic surgery resulted in significant improvement for all four major symptoms pain, numbness, paresthesia, and weakness. From multivariate logistic regression, a shorter distal sensory latency is associated with a higher likelihood of a good outcome (P = 0.058; odds ratio, 0.912; 95% confidence interval, 0.828-1.0) only for paresthesia. The other factors were not found to be significant (all P > 0.10). The area under the curve (AUC) was 0.69 (95% confidence interval for AUC, 0.50-0.88). A cutoff of 6.0 ms or lower for sensory latency predicts for good outcome (in terms of paresthesia score) with the sensitivity/certainty of 84.6% and positive predictive value of 86.8%. A receiver operating characteristic analysis of baseline paresthesia score for good outcome of the paraesthesia domain showed that the AUC was 0.967 (95% confidence interval for AUC, 0-1.0). At a cutoff of baseline paraesthesia score of 4 or above, prediction for good outcome achieved a sensitivity of 87.2% and positive predictive value of 97.1%.

CONCLUSIONS

A shorter distal sensory latency is associated with a higher likelihood of a good outcome for paraesthesia. In addition, patients with baseline of 4 or above had correlated with better surgical outcome than those with less severe symptoms. Our data thus suggest that surgical benefit is best seen in patients with moderate symptoms, in combination with electrophysiological evidence of early demyelination, as a possible therapeutic window.

Position Change of the Neurovascular Structures around the Carpal Tunnel with Dynamic Wrist Motion

OBJECTIVE

The purpose of this study was to determine the anatomic relationships between neurovascular structures and the transverse carpal ligament so as to avoid complications during endoscopic carpal tunnel surgery.

METHODS

Twenty-eight patients (age range, 35-69 years) with carpal tunnel syndrome were entered into the study. We examined through wrist magnetic resonance imaging in three different positions (neutral, radial flexion, and ulnar flexion) and determined several anatomic landmark (distance from the hamate hook to the median nerve, ulnar nerve, and ulnar vessel) based on the lateral margin of the hook of the hamate. The median nerve and ulnar neurovascular structure were studied with the wrist in the neutral, ulnar, and radial flexion positions.

RESULTS

The ulnar neurovascular structures usually passed just over or ulnar to the hook of the hamate. However, in 12 hands, a looped ulnar artery coursed 0.6-3.3 mm radial to the hook of the hamate and continued to the superficial palmar arch. The looped ulnar artery migrates on the ulnar side of Guyon's canal (-5.2-1.8 mm radial to the hook of the hamate) with the wrist in radial flexion. During ulnar flexion of the wrist, the ulnar artery shifts more radially beyond the hook of the hamate (-2.5-5.7 mm).

CONCLUSION

It is appropriate to transect the ligament greater than 4 mm apart from the lateral margin of the hook of the hamate without placing the edge of the scalpel toward the ulnar side. We would also recommend not transecting the transverse carpal ligament in the ulnar flexed wrist position to protect the ulnar neurovascular structure.

Single portal endoscopic carpal tunnel release: modification of Menon's technique and data from 65 cases

The purpose of our study is to make a follow-up evaluation of endoscopic carpal tunnel release under focal anesthesia using the Wolf single portal system. A total of 65 patients with a mean age of 50 years undergoing 79 procedures were retrospectively studied. Preoperative complaints, intraoperative findings, and postoperative results of all the patients were recorded. Follow-up was conducted at 1, 5, 12, and 24 weeks and at 1 year postoperatively. Wound pain, analysis of satisfaction, Levine functional status scales, and surgical complications were included. No patients sustained iatrogenic neurovascular injury or hematoma formation. The average Levine functional severity score decreased from 2.82 points preoperatively to 1.2 points at the most recent survey. One case recurred at 1 year after the surgery and subsequently underwent open release. Surgery using the Wolf single portal system under focal anesthesia is a safe and efficacious option for endoscopic carpal tunnel release.

Carpal tunnel syndrome: treatment with small transverse incision

OBJECTIVE: To evaluate the application of a limited transverse incision technique to treat the carpal tunnel syndrome, with concern to its safety and efficacy in the opening of the flexor retinaculum (FR). METHOD: A prospective analysis of thirty FR release procedures performed on twenty-eight patients subjected to the proposed incision technique. Safety and total opening of the FR were evaluated through a questionnaire and an endoscopic inspection respectively. RESULTS: No major complications were observed. Two cases presented small local hematoma. One patient presented with transient neuropraxia of digital branch. In two of the first five cases, incomplete FR opening was identified during endoscopic revision with need of complementary opening. All patients reported relief of paresthesias and nocturnal pain symptoms. CONCLUSION: The technique was safely performed on the prospection group, no major complications were detected and the opening of FR was observed in the majority of the patients.