Percutaneous ultrasound-guided MANOS carpal tunnel release technique

Ultrasound-guided minimally invasive thread release of carpal tunnel: a cadaveric study

PURPOSE

Thread release of the carpal tunnel is the most recent of several minimally invasive ultrasound-guided carpal tunnel release techniques. The purpose of this article is to provide a step-by-step guide for minimally invasive, ultrasound-guided thread release of the carpal tunnel focused on transecting the transverse carpal ligament with minimal damage to the palmar aponeurosis on anatomical specimens.

METHODS

Fifteen ultrasound-guided carpal tunnel thread releases were performed on the wrists of soft-embalmed anatomical specimens, which were dissected immediately after the intervention. The procedures were performed by two musculoskeletal radiologists with 25 and 8 years of experience, respectively, in interventional radiology. Ultrasound visibility, completeness of transection, and damage to surrounding structures were evaluated on a score from 1 to 3.

RESULTS

We achieved a complete transection of the transverse carpal ligament in 11 of 15 interventions (73%) and an incomplete transection in the remaining four (27%). No neural or vascular structures were harmed. In two cases (13%), there was irrelevant damage to flexor tendons. The ultrasound visibility was rough in five specimens (33.3%), moderate in five (33.3%), and optimal in five (33.3%). Essential structures were delineated in all cases.

CONCLUSION

Thread release of the carpal tunnel leads to only minimal damage to skin, as well as structures within the carpal tunnel and the palmar aponeurosis, promising a low amount of postinterventional complications.

RELEVANCE STATEMENT

Our study showed that minimally invasive ultrasound-guided thread release of the carpal tunnel is a feasible approach in the anatomical model. The results may provide a basis for further research and refinement of this technique.

Ultrasound-guided interventions in primary carpal tunnel syndrome: perineural injection to thread carpal tunnel release

Carpal tunnel syndrome (CTS), the most common entrapment neuropathy, is compression of the median nerve deep to transverse carpal ligament at wrist. Ultrasonography and electrophysiological study are complementary in the diagnosis and grading of CTS in appropriate clinical settings. The initial management of patients with CTS is conservative with medical therapy and splinting. However, surgical interventions are indicated in patients in whom medical management has failed. With evolution of the concept of safe zone on ultrasonography and identification of the sonoanatomical landmarks of carpal tunnel in greater detail, Ultrasonography-guided interventions are safer and preferred over surgical management in CTS. The primary ultrasonography-guided interventions include perineural injection, perineural hydrodissection and ultrasonography-guided release of transverse carpal ligament. This review article presents the principles of ultrasonography-guided perineural injection, perineural hydrodissection in CTS, the merits and demerits of injectant used in perineural injection/ hydrodissection, and percutaneous ultrasonography-guided thread release of transverse carpal ligament utilizing the concept of safe zone of the ultrasonography-guided interventions for CTS.

Long-term Clinical Results of Carpal Tunnel Release Using Ultrasound Guidance

BACKGROUND

The purpose of this study was to determine the long-term safety and efficacy of carpal tunnel release (CTR) using ultrasound guidance in a group of patients treated by a single physician.

METHODS

The study group consisted of 76 consecutive CTRs performed on 47 patients between June 2017 and April 2019 for whom 1-year follow-up was available. All procedures were performed by the same operator using a single CTR technique. Outcomes included complications; Boston Carpal Tunnel Questionnaire symptom severity (BCTQ-SSS) and functional status (BCTQ-FSS) scores; Quick Disabilities of the Arm, Shoulder, and Hand (QDASH) scores; and a 5-point global satisfaction score (4 = satisfied, 5 = very satisfied).

RESULTS

The 47 patients included 27 females and 20 males (ages 31-91 years). Twenty-five patients (50 hands) had simultaneous bilateral CTRs, 4 patients (8 hands) had staged bilateral CTRs, and 18 patients had unilateral CTRs. No complications occurred. Statistically and clinically significant reductions in BCTQ-SSS, BCTQ-FSS, and QDASH scores occurred by 1 to 2 weeks post-CTR and persisted at 1-year (mean 1-year changes vs. pre-CTR -2.11, -1.70, and -44.99, respectively; P < .001 for all). The mean global satisfaction score at 1-year was 4.63.

CONCLUSIONS

CTR using ultrasound (US) guidance is a safe and effective procedure that produces statistically and clinically significant improvements within 1 to 2 weeks postprocedure that persist to 1 year. Furthermore, simultaneous bilateral CTRs using US guidance are feasible and may be advantageous for patients who are candidates for bilateral CTR.

Trial of ultrasound guided carpal tunnel release versus traditional open release (TUTOR)

BACKGROUND

Carpal tunnel release (CTR) is a surgical treatment option for patients with carpal tunnel syndrome (CTS) symptoms that are unresponsive to conservative treatment. Most patients experience symptomatic relief after CTR regardless of the surgical technique. However, direct comparisons of the safety and effectiveness between CTR surgical techniques are limited. The purpose of this randomized controlled trial is to compare the safety and effectiveness of CTR with ultrasound guidance (CTR-US) versus mini-open CTR (mOCTR) in subjects with symptomatic CTS.

DESIGN AND METHODS

TUTOR (Trial of Ultrasound guided CTR versus Traditional Open Release) is a randomized controlled trial in which 120 subjects at up to 12 sites in the United States will be randomized (2:1) to receive CTR-US or mOCTR. The primary endpoint of the study is the percentage of patients who return to normal daily activities within 3 days of the procedure. Secondary endpoints of the study are median time to return to normal daily activities, percentage of patients who return to work within 3 days of the procedure, median time to return to work, Boston Carpal Tunnel Questionnaire Symptom Severity Scale (BCTQ-SSS) change score at 3 months, BCTQ Functional Status Scale (BCTQ-FSS) change score at 3 months, Numeric Pain Scale change score at 3 months, EuroQoL-5 Dimension 5-Level (EQ-5D-5L) change score at 3 months, and the incidence of device- or procedure-related adverse events at 3 months. Patient follow-up in this trial will continue for 1 year.

ETHICS AND DISSEMINATION

This study was approved by a central institutional review board and ongoing trial oversight will be provided by a data safety monitoring board (DSMB). The authors intend to report the results of this trial at medical conferences and peer-reviewed journals. The outcomes of TUTOR will have important clinical and economic implications for all stakeholders involved in treating patients with CTS.

STUDY REGISTRATION

ClinicalTrials.gov (https://clinicaltrials.gov): NCT05405218.

LEVEL OF EVIDENCE

1.

Ultrasound-Guided Partial Plantar Fascia Release with the Use of a Fine Cutting Device for the Treatment of Persistent Plantar Fasciitis: A Case Series

BACKGROUND

Plantar fasciitis is a common cause of musculoskeletal discomfort. Minimally invasive interventions are preferred as second-line treatments following failure of conservative management. We report on a novel technique of ultrasound-guided percutaneous release of the medial third of the plantar fascia with the use of a fine cutting device for the treatment of persistent plantar fasciitis.

METHODS

This is a retrospective case series of all patients treated with the technique between 2013 and 2015. Patients had failed conservative management for a minimum of 6 months. The procedure was performed in an outpatient setting under local anesthesia. Under continuous ultrasound guidance, release of the medial third of the plantar fascia from the calcaneus was performed using an ophthalmic V-Lance knife through a medial stab wound entry point.

RESULTS

Fifteen patients (six men and nine women) with an average age of 54.7 years were included. The mean (standard deviation [SD]) visual analogue scale score for pain improved significantly, from 66.0 (SD, 18.8) preoperatively to each consecutive follow-up point: 29.3 (SD, 25.2) at 2 weeks, 30.0 (SD, 27.8) at 4 weeks, and 34.0 (SD, 26.1) at 12 weeks (P < .001). The mild increase in visual analogue scale score between 4 and 12 weeks was statistically significant (P = .018). Average duration of required analgesia was 5.5 days and average time required to return to usual activities was 5.7 days. Two patients suffered with refractory neuropathic pain over the lateral border of the foot without any obvious abnormality.

CONCLUSIONS

Ultrasound-guided percutaneous release with the use of a fine cutting device could be an alternative option for the treatment of persistent plantar fasciitis. The technique is not without complications, and a mild but statistically significant decline in pain levels from early to short term has been detected. Therefore, the long-term outcomes of this technique need to be investigated before we can advocate its routine use.

Percutaneous Sonographically Guided Release of Carpal Tunnel and Trigger Finger: Biomechanics, Clinical Results, Technical Developments

The interventional use of sonography is growing fast, and percutaneous sonographically guided release is more and more used as minimally invasive treatment of carpal tunnel syndrome as well as trigger finger digit. The benefits of these procedures seem promising in clinical studies, but biomechanical studies comparing these procedures with open classical surgery are scarce. Minimally invasive releases of carpal tunnel and trigger finger could limit the phenomenon of tendon bowstringing observed after open surgery. A new model is presented to compare the biomechanical effects of open and sono-guided carpal tunnel and trigger finger releases.

Cost-Effectiveness of Sonography-Guided Surgery

Percutaneous carpal tunnel release (CTR) is a new surgical technique allowing to cut the transverse carpal ligament under sonography, without skin incision. The technique is safe, offers good functional results and early return to daily activities. This study investigates if percutaneous CTR is also cost-effective. Percutaneous CTR presents many advantages and may be safer than open and endoscopic CTR. This study could not demonstrate that it allows also cheaper surgery, at least as compared to open CTR. However, if it allows earlier return to work, percutaneous CTR could offer a major economic advantage over other techniques, particularly open surgery.

Safe Zones for Percutaneous Carpal Tunnel Release

Carpal tunnel release (CTR) is an effective procedure used in open, endoscopic, or ultrasound-guided methods. The complications are rare but potentially devasting. Most complications come from errors related to intraoperative technique, especially in the minimally invasive approach. An understanding of the "safe zones" is essential to perform percutaneous CTR safely. This article reviews the anatomy of safe zones and the ultrasound-guided CTR (UCTR) techniques in an attempt to prevent intraoperative complications. In strict accordance with the concepts of safe zones, UCTR is an effective and reliable procedure. Substantial experience for ultrasound-guided injection and surgery is required.

Minimally Invasive Ultrasound-Guided Carpal Tunnel Release Improves Long-Term Clinical Outcomes in Carpal Tunnel Syndrome

BACKGROUND. Ultrasound guidance allows performance of carpal tunnel release with smaller incisions and quicker recovery than traditional open or endoscopic surgery. OBJECTIVE. The purpose of this study was to evaluate the long-term effectiveness of ultrasound-guided carpal tunnel release in improving function and discomfort in patients with carpal tunnel syndrome. METHODS. Retrospective review was conducted of 61 ultrasound-guided carpal tunnel release procedures performed on 46 patients (15 bilateral procedures) with clinically diagnosed carpal tunnel syndrome. The procedures were performed with a single-use transection device and local anesthesia at an outpatient radiology office. Patients answered three questionnaires (Quick Disabilities of the Arm, Shoulder, and Hand [QDASH] and two parts of the Boston Carpal Tunnel Syndrome Questionnaire-the symptom severity [BCTSQ-SS] and functional status [BCTSQ-FS] scales) to assess the function of and discomfort in the affected wrist immediately before and 2 weeks and at least 1 year after the procedure. Higher scores indicated increasing disability. Patients also answered a global satisfaction question at follow-up. Preprocedure and postprocedure scores were compared by paired Wilcoxon signed rank tests. RESULTS. The 46 patients (25 women, 21 men; mean age, 60.6 years; range, 21-80 years) had median preprocedure scores of 45.4 for QDASH, 3.2 for BCTSQ-SS, and 2.5 for BCTSQ-FS. The median scores 2 weeks after the procedure were 22.5 for QDASH, 1.7 for BCTSQ-SS, and 1.9 for BCTSQ-FS. All scores decreased (p < .001) from preprocedure scores and surpassed reference standards for clinically important difference in scores. Follow-up questionnaires obtained for 90% (55/61) of wrists a median of 1.7 years (range, 1.0-2.8 years) after the procedure showed further declines (p < .001) in median scores: 2.3 for QDASH, 1.2 for BCTSQ-SS, and 1.1 for BCTSQ-FS. At long-term follow-up evaluation, 96% (52/54) of wrists had lower QDASH and 98% (53/54) had lower BCTSQ (average of BCTSQ-SS and BCTSQ-FS) scores compared with the preprocedure scores. Among the patients who participated in the survey, 93% (37/40) were satisfied or very satisfied with the long-term outcomes. No immediately postoperative complications occurred. Two patients needed surgical intervention 8 and 10 days after surgery, one for infection after injury and one for posttraumatic compartment syndrome. CONCLUSION. Ultrasound-guided carpal tunnel release quickly improves hand function and reduces hand discomfort; improvement persists beyond 1 year. CLINICAL IMPACT. Ultrasound-guided carpal tunnel release may be a safe, effective, and less invasive alternative to traditional surgery.

A Controlled Trial Evaluating the Safety and Effectiveness of Ultrasound-Guided Looped Thread Carpal Tunnel Release

Background: Open carpal tunnel release typically requires several weeks of recovery. A less invasive, ultrasound-guided percutaneous technique of releasing the transverse carpal ligament using a thread (thread carpal tunnel release [TCTR]) has been described. To date, its clinical effectiveness and safety have been evaluated exclusively by the group that developed the technique, using a single outcome measure without a control comparison. The objective of this study was to independently evaluate the safety and effectiveness of TCTR using multiple outcome measures and a control comparison. Methods: A convenience sample of 20 participants with refractory moderate or severe carpal tunnel syndrome underwent TCTR of their most symptomatic hand. Outcome measures included pre-TCTR and 1-, 3-, and 6-month post-TCTR Boston questionnaire; pre-, 3-, and 6-month post-TCTR monofilament sensibility, strength, ultrasound, and electrodiagnostic testing; weekly post-TCTR phone interviews for 1 month; and satisfaction surveys at 3 and 6 months post-TCTR. Results: No complications were reported. During the month post-TCTR, significant prompt improvements in hand pain and dysfunction occurred. The following significant improvements were demonstrated in the treated versus control hand: Boston Questionnaire scores, median nerve distal motor latency, transcarpal tunnel motor and sensory conduction velocities and sensory nerve action potential amplitudes. No significant differences in sensibility, pinch or grip strength, median nerve cross-sectional area (CSA) at the carpal tunnel inlet, or wrist: forearm median nerve CSA ratio were documented between TCTR and control sides. Satisfaction with the TCTR procedure was high (85%-90%). Conclusions: This study supports previous reports that the TCTR procedure is safe and effective.

An Incision-less Ultrasound-guided Carpal Tunnel Release Technique

Ultrasound guidance in the operative treatment of carpal tunnel syndrome is gaining in popularity as it noninvasively provides the surgeon with a real-time high-resolution overview of anatomic structures. A new incision-less approach to achieve a division of the transverse carpal ligament has been developed that combines ultrasound guidance with cannulated needles and a thread. Conceptually, an abrasive thread is looped percutaneously around the ligament while avoiding injury to neurovascular structures, the palmar aponeurosis, and skin. The thread is positioned using 2 puncture sites and a contoured Tuohy needle under ultrasound visualization. With a minimal injury to surrounding structures, this approach is designed to minimize recovery time and decrease pillar pain. This article will provide a step-by-step overview of the technique and includes a review of clinical outcomes published so far.

Clinical Results of Ultrasound-Guided Carpal Tunnel Release Performed by a Primary Care Sports Medicine Physician

OBJECTIVES

The purpose of this study was to determine the safety and efficacy of ultrasound-guided carpal tunnel release (USCTR) in a consecutive group of patients treated by a single primary care sports medicine physician.

METHODS

The study group consisted of 35 USCTRs performed on 22 consecutive patients for whom clinical outcomes were available before USCTR and at 1 to 2 weeks, 1 month, and 3 months after USCTR. All procedures were performed by the same operator using a single USCTR technique. Outcomes included complications, Quick Disabilities of the Arm, Shoulder, and Hand scores, Boston Carpal Tunnel Questionnaire symptom severity and functional status scores, and a 5-point global satisfaction score.

RESULTS

The 22 patients included 13 female and 9 male patients (ages 31-82 years). Eleven patients (22 wrists) had bilateral simultaneous USCTRs; 2 patients (4 wrists) had staged bilateral USCTRs; and 9 patients had unilateral USCTRs. No complications occurred in any patient. Statistically and clinically significant reductions in Quick Disabilities of the Arm, Shoulder, and Hand scores and Boston Carpal Tunnel Questionnaire symptom severity and functional status scores occurred by 1 to 2 weeks after USCTR (mean 1- to 2-week changes, -29.23, -1.74, and -1.18, respectively), and further improvements occurred during the 3-month follow-up period (mean 3-month changes, -51.11, -2.29, and -1.91; P < .0001 for all values versus before USCTR). Mean global satisfaction scores at 1 to 2 weeks and 3 months were 4.63 and 4.66.

CONCLUSIONS

Ultrasound-guided CTR is a safe and effective procedure that can be performed by an experienced primary care sports medicine physician and typically results in significant improvements within the first 2 weeks after the procedure. Furthermore, bilateral simultaneous USCTRs are feasible and may provide significant advantages for patients who are candidates for bilateral CTRs.

Ultrasound-guided percutaneous carpal tunnel release in patients on hemodialysis: early experiences and clinical outcomes

Purpose: The purpose of the current study was to evaluate the effectiveness of ultrasound-guided percutaneous carpal tunnel release in hemodialysis patients with carpal tunnel syndrome.

Methods: From February 2009 to April 2013, a prospective review of 113 consecutive cases of ultrasound-guided percutaneous carpal tunnel release was carried out in 84 hemodialysis patients. Results were analyzed by clinical subjective scale, two self-administered questionnaires, and functional evaluations at seven time points (1 week and 1, 3, 6, 12, 18, and 24 months).

Results: Satisfactory symptom improvement in patients was 82%, 80%, 86%, 89%, 90%, 91%, and 90% at 1 week and 1, 3, 6, 12, 18, and 24 months postoperatively, respectively. Moderate pain was suffered in 11.5% of patients within 1 week, 8.8% within 1 month, 2.7% within 3 months, and none after 12 months postoperatively. Static two-point discrimination and Semmes–Weinstein monofilament examinations presented significant improvements after 1 week and 1 month postoperatively and with time. Postoperative grip power demonstrated recovery and a significant increase after 3 and 6 months postoperatively. Three-jaw chuck-pinch strength showed significant increase after 1 month postoperatively. There were no operative complications.

Conclusion: Ultrasound-guided percutaneous carpal tunnel release is an effective and safe procedure in hemodialysis patients with carpal tunnel syndrome. The advantages include a less invasive procedure, no tourniquet needed, only limited infiltration anesthesia, minimal soft-tissue exploration, and relatively short operation time. Our data suggest this technique can reliably relieve clinical symptoms, with early restoration of grip and pinch strength.

[Carpal tunnel syndrome secondary to a rare anatomical variation of the median nerve]

Carpal tunnel syndrome is one of the the most common reasons for consultation in hand surgery with an annual incidence of 300 per 100 000 inhabitants and, in France, of 80 000 surgical interventions. In most cases, carpal tunnel syndrome is idiopathic occurring without a recognizable cause. However, beyond these forms, the merging of several mechanisms can explain the cause-and-effect relationship of this pathology . This study aimed to highlight an exceptional association of a carpal tunnel syndrome secondary to a rare anatomical variety of the median nerve.

The Effectiveness of Ultrasound-Guided Steroid Injection Combined with Miniscalpel-Needle Release in the Treatment of Carpal Tunnel Syndrome vs. Steroid Injection Alone: A Randomized Controlled Study

Objectives

Carpal tunnel syndrome (CTS) is one of the most common nerve entrapment syndromes, which has a serious impact on patients' work and life. The most effective conservative treatment is steroid injection but its long-term efficacy is still not satisfactory. The aim of this study was to evaluate the effectiveness of steroid injection combined with miniscalpel-needle (MSN) release for treatment of CTS under ultrasound guidance versus steroid injection alone. We hypothesized that combined therapy could be more beneficial.

Methods

Fifty-one patients with CTS were randomly allocated into two groups, namely, steroid injection combined with MSN release group and steroid injection group. The therapeutic effectiveness was evaluated using Boston Carpal Tunnel Questionnaire (BCTQ), cross-sectional area (CSA) of the median nerve, and four electrophysiological parameters, including distal motor latency (DML), compound muscle action potential (CMAP), sensory nerve action potential (SNAP), and sensory nerve conduction velocity (SNCV) at baseline, 4 and 12 weeks after treatment.

Results

Compared with baseline, all the parameters in both groups showed statistically significant improvement at week 4 and week 12 follow-up, respectively (P<0.05). When compared with steroid injection group, the outcomes including BCTQ, DML, CMAP, SNCV, and CSA of the median nerve were significantly better in steroid injection combined with MSN release group at week 12 after treatment (P<0.05).

Conclusions

The effectiveness of steroid injection combined with MSN release for CTS is superior to that of steroid injection alone, which may have important implications for future clinical practice. This Chinese clinical trial is registered with ChiCTR1800014530.

Ultrasound-guided percutaneous compartment release: a novel technique, proof of concept, and clinical relevance

OBJECTIVE

Ultrasound-guided thread release (USGTR) is a minimally invasive technique with excellent clinical outcomes currently used in clinical practice to divide the transverse carpal ligament in carpal tunnel syndrome. The purpose of this study is to determine whether this technique can be modified for use in large anatomical compartments in soft embalmed cadaveric models.

MATERIALS AND METHODS

Two operators adapted the USGTR technique for use in muscular compartments of the forearms and legs in a single soft embalmed cadaver. An iterative approach was used to adapt and improve the technique for use in large compartments, using equipment readily available in most radiology departments.

RESULTS

The USGTR technique was successfully modified and both operators were able to accurately divide fascial layers over distances of up to 30 cm using the modified technique. Fascial division was confirmed with ultrasound and dissection.

CONCLUSIONS

This adapted technique can successfully be used to divide fascial planes over longer distances than is currently achieved in clinical practice. The improved outcomes associated with USGTR at the carpal tunnel may therefore also be achievable in fasciotomy procedures in larger anatomical compartments. Further study is required to investigate the effects of this modified USGTR technique on intracompartmental pressure.

Ultrasound-Guided Surgery for Carpal Tunnel Syndrome: A New Interventional Procedure

Carpal tunnel syndrome (CTS) may be treated surgically if medical treatment fails. The classical approach involves release of the flexor retinaculum by endoscopic or open surgery. Meta-analyses have shown that the risk of nerve injury may be higher with endoscopic treatment. The recent contribution of ultrasound to the diagnosis and therapeutic management of CTS opens new perspectives. Ultrasound-guided carpal tunnel release via a minimally invasive approach enables the whole operation to be performed as a percutaneous radiological procedure. The advantages are a smaller incision compared with classical techniques; great safety during the procedure by visualization of anatomic structures, particularly variations in the median nerve; and realization of the procedure under local anesthesia. These advantages lead to a reduction in postsurgical sequelae and more rapid resumption of daily activities and work. Dressings are removed by the third day postsurgery. Recent studies seem to confirm the medical, economic, and aesthetic benefits of this new approach.

Percutaneous Ultrasound-Guided Carpal Tunnel Release: Study Upon Clinical Efficacy and Safety

Objectives

To evaluate the feasibility and 6 months clinical result of sectioning of the transverse carpal ligament (TCL) and median nerve decompression after ultra-minimally invasive, ultrasound-guided percutaneous carpal tunnel release (PCTR) surgery.

Methods

Consecutive patients with carpal tunnel syndrome were enrolled in this descriptive, open-label study. The procedure was performed in the interventional radiology room. Magnetic resonance imaging was performed at baseline and 1 month. The Boston Carpal Tunnel Questionnaire was administered at baseline, 1, and 6 months.

Results

129 patients were enrolled. Significant decreases in mean symptom severity scores (3.3 ± 0.7 at baseline, 1.7 ± 0.4 at Month 1, 1.3 ± 0.3 at Month 6) and mean functional status scores (2.6 ± 1.1 at baseline, 1.6 ± 0.4 at Month 1, 1.3 ± 0.5 at Month 6) were noted. Magnetic resonance imaging showed a complete section of all TCL and nerve decompression in 100% of patients. No complications were identified.

Conclusions

Ultrasound-guided PCTR was used successfully to section the TCL, decompress the median nerve, and reduce self-reported symptoms.

Sonographic Visualization of Thenar Motor Branch of the Median Nerve: A Cadaveric Validation Study

BACKGROUND

The thenar motor branch (TMB) of the median nerve may be affected in carpal tunnel syndrome and can be injured during carpal tunnel surgery. Although ultrasound has been used to identify small nerves throughout the body, the sonographic evaluation of the TMB has not been investigated formally.

OBJECTIVE

To document the ability of ultrasound to visualize the TMB of the median nerve in an unembalmed cadaveric model.

DESIGN

Prospective laboratory investigation.

SETTING

Procedural skills laboratory at a tertiary medical center.

METHODS

On the basis of anatomical descriptions, dissection and clinical experience, a technique was developed to sonographically identify the presumed TMB of the median nerve at the distal carpal tunnel. A single, experienced examiner then identified the presumed TMB in 10 unembalmed, cadaveric upper limb specimens (4 right, 6 left) obtained from 9 donors (4 male, 5 female) ages 76-85 years with body mass indices of 18.2-29.5 kg/m² with both 12-3 MHZ and 16-7 MHz linear array transducers. The same examiner then injected 0.2-0.3 mL of diluted colored latex into and around the presumed TMB using direct ultrasound guidance. At a minimum of 24 hours postinjection, specimens were dissected under loupe magnification to determine the location of the latex injectate.

MAIN OUTCOME MEASURE

The location of latex injectate relative to the anatomically identified TMB.

RESULTS

A vertical, linear, hypoechogenic region was sonographically identified arising from the median nerve at the distal carpal tunnel in all 10 specimens and was hypothesized to represent the vertical segment of the TMB. Both transducers allowed identification of the TMB, although localization was subjectively facilitated by the higher frequency transducer. All 10 sonographically guided injections placed latex into and around the TMB of the median nerve, confirming that ultrasound had accurately identified the TMB.

CONCLUSIONS

Sonographic evaluation of the TMB of the median nerve is technically feasible and should be considered when clinically indicated. Further research and clinical experience is necessary to define the role of sonographic TMB imaging in the evaluation and management of patients with carpal tunnel syndrome.

LEVEL OF EVIDENCE

IV.

A non-scalpel technique for minimally invasive surgery: percutaneously looped thread transection of the transverse carpal ligament

PURPOSE

This study aims to develop an alternate technique for improving the surgical procedure of carpal tunnel release.

METHOD

The transverse carpal ligament is transected by utilizing a piece of thread looped percutaneously under the visualization of ultrasound. The procedure, the thread carpal tunnel release (TCTR), was performed on 34 hands of 20 patients. Self-administrated Levine-Katz questionnaire was used for assessing the symptom severity and functional status of the outcomes.

RESULTS

TCTR was performed in each case with no unintended consequences. The average duration for a procedure was 7 min, excluding time of preparation. Significant improvements in subjective sensibility were reported within 24 h, and sleep quality improved for all cases. There were no postoperative complications. The scores of questionnaire 3 months postoperatively were comparable to the literature controls.

CONCLUSION

TCTR is a safe and effective minimally invasive surgery performed under local anesthesia in a clinic-based procedure room and results in only one-needle entrance point at the wrist and one-needle exit point in the palm. The feature of the procedure includes the potentials of reduced risk of iatrogenic injury, reduced surgical cost, and reduced patient recovery time. The study has shown encouraging promise for optimizing the technique of carpal tunnel release, and more clinical trials are necessary to confirm the findings.