Carpal tunnel release: do we understand the biomechanical consequences?

Volar Lunate Dislocation Causing Secondary Carpal Tunnel Syndrome: A Case Report

Background  Failure of carpal tunnel release is an uncommon occurrence with unique pathologies that may impede proper diagnosis and treatment. Symptoms are most often attributed to an inadequate release of the transverse carpal ligament or pathologic scar tissue resultant of the primary decompression. Case Description  In this report, we describe the case of a 79-year-old male with a history of scaphoid lunate advanced collapse and a prior carpal tunnel decompression presenting with worsening right wrist function and new right palmar mass. The patient had no significant antecedent trauma, and clinical workup revealed volar dislocation of the lunate. After failed conservative treatment and multiple ultrasound-guided corticosteroid injections, the patient was successfully treated surgically with carpal tunnel release, tenosynovectomy, and lunate excision. Literature Review  Volar lunate dislocation without a traumatic mechanism is rare. Progressive carpal destabilization and volar subluxation is not a commonly reported cause of secondary carpal tunnel symptoms. Isolated reports in the literature have been published with nearly identical presentations. Kamihata et al reported a patient, with a history of carpal tunnel decompression, presenting with numbness and tingling in her right hand without traumatic injury. A displaced lunate was found to abut the flexor tendons and median nerve. Ott et al further reported an atraumatic lunate dislocation and palmar swelling 4 weeks after a carpal tunnel release. Clinical Relevance  In the setting of existing arthritic degeneration, carpal tunnel release may destabilize the carpus and predispose patients to carpal dislocation. Further research is required to understand the risks associated with this instability leading to lunate dislocations secondary to carpal tunnel release.

Identifying anatomic landmarks and median nerve characteristics for the analysis of persistent carpal tunnel syndrome using magnetic resonance imaging (MRI)

OBJECTIVE

Carpal tunnel syndrome (CTS) is the most common nerve entrapment neuropathy in the USA. In this study, we define anatomical landmarks to assess symptomatic and asymptomatic cohorts with persistent CTS using MRI imaging.

MATERIALS AND METHODS

Distal vs proximal incomplete release was determined using the distal most aspect of the hook of hamate and the distal wrist crease. An incomplete release showed the transverse carpal ligament (TCL) intact at either boundary. Twenty-one patients with persistent CTS were analyzed for incomplete release, median nerve enlargement and T2 signal hyperintensity, and flattening ratio using postoperative wrist MRI. These findings were compared to a ten-patient asymptomatic persistent CTS control group. Fisher's exact and a Student's two-tailed t-tests were used to determine statistical significance.

RESULTS

In the symptomatic persistent CTS group, 13 (61.9%) incomplete releases were identified, 5 (38.5%) incomplete distally, and 1 (7.7%) incomplete proximally. There was no statistical significance in the rate of incomplete releases when compared to the asymptomatic group (p = 1.00). T2 signal hyperintensity and enlargement at the site of release showed no statistical significance, (p = 0.319 and p = 0.999, respectively). The mean flattening ratio at the site of release in the symptomatic group (2.45 ± 0.7) was statistically significant compared to the asymptomatic group (1.48 ± 0.46), (p = 0.007).

CONCLUSION

Utilizing the established landmarks, the full length of the TCL can be assessed via MRI. Additionally, evaluation of the median nerve flattening ratio at the level of the incomplete release may be utilized as an aid to the clinical management of persistent CTS.

Carpal Dimensions by Plain Wrist Radiography in Patients with Severe Carpal Tunnel Syndrome

In this study, we evaluated the diagnostic value of carpal dimensions in wrist plain radiography for the screening of carpal tunnel syndrome (CTS). This is a case-control diagnostic probe in which patients with severe CTS documented by electrodiagnostic study and healthy subjects as controls were enrolled. In the posteroanterior view of the wrist plain radiography in both groups, we defined and measured the carpal ratio, and the results were analyzed deploying statistical software. In this study, 119 participants, including 50 patients and 69 healthy subjects, were recruited. According to the ROC chart, the cutoff points, positive and negative predictive values, and the diagnostic accuracy for the cutoff points were calculated.

Presentation and outcome of carpal tunnel syndrome with mini incision open carpal tunnel release

Background: To document the clinical presentation of carpal tunnel syndrome (CTS) and evaluate the outcome of mini-incision open carpal tunnel release in terms of surgical complications, relief/persistence of symptoms at 4 months, and recurrence at 1 year. Methods: This prospective case series included patients of all genders and ages who presented with CTS. They underwent release of transverse carpal ligament (TCL) under local anesthesia and tourniquet control on day care basis. Mini-incision of 2 cm to 2.5 cm was employed. The data were subjected to statistical analysis using SPSS version 21 (SPSS Inc). The percentages of key categorical variables were compared by employing the chi square test, and a P value of less than.05 was regarded as statistically significant. Results: There were 67 patients with 77 CTS affected wrists. A Significant majority of the patients (n = 54; 80.59%) were females, whereas 13 (19.40%) patients were males. The age range was 26 to 69 years, with a mean age of 41.01 ± 11.70 years. The CTS was found to be moderate among 34 (44.15%) and severe among 43 (55.84%) patients. The majority of patients had no operative complications. At 4 months follow-up, the majority of patients (n = 74; 96.10%) reported symptomatic relief, whereas 3 (3.89%) patients continued to have persistent severe symptoms. All the cases with persistent symptoms had diabetes mellitus of more than 5 years duration. There was no case of recurrence at one year follow-up. Conclusion: CTS predominantly affected women aged 30 to 45 years. The open carpal tunnel release with mini-incision yielded good results in terms of relieving symptoms among the majority of patients and was associated with no critical complications or recurrence at 1 year.

The Influence of Transverse Carpal Ligament Thickness on Treatment Decisions for Idiopathic Mild to Moderate Carpal Tunnel Syndrome

PURPOSE

The main cause of carpal tunnel syndrome (CTS) is pathological changes in the flexor synovium, which is a known cause of pressure elevation in the carpal tunnel. The importance of the transverse carpal ligament (TCL) in the pathogenesis of CTS has hitherto been overlooked. However, the TCL significantly affects carpal biomechanics; the TCL is known to affect the carpal bone to a greater extent when intra carpal tunnel pressure is high. In addition, the effect of TCL properties on the progression course of idiopathic CTS is unknown.Therefore, we hypothesized that TCL thickness, measured using ultrasonography, would influence the results of conservative treatment for CTS patients with mild to moderate symptoms. We aimed to investigate the relationship between the ultrasound-measured TCL thickness and idiopathic carpal tunnel conservative treatment surgery rate.

MATERIALS AND METHODS

We analyzed the wrists of 127 patients with mild to moderate symptoms of CTS. The patients were diagnosed on the basis of electrophysiological assessment outcomes, median nerve cross-sectional area in the carpal tunnel, and clinical symptoms. The Boston carpal tunnel questionnaire score was also measured. Patients with a TCL thinner than 1.5 mm were classified into group A (n = 62), and those with a TCL thicker than 1.5 mm were classified into group B (n = 65). Patients with severe symptoms or other diseases were excluded. The patients were initially treated with night splinting after diagnosis. If symptoms were not ameliorated, steroid injection and surgical treatment were performed consecutively. The procedures were determined by a single surgeon.

RESULTS

The mean TCL thickness was 1.51 mm: 0.98 mm in group A and 2.28 mm in group B. The percentages of patients who underwent surgery were 43.0% in group A and 67.7% in group B. Group B was 1.77 times more likely to have surgery, and the interval between diagnosis and surgery and/or steroid injection was shorter. The TCL thickness in group B was also related to cross-sectional area and symptom duration.

CONCLUSIONS

Transverse carpal ligament thickness affects disease progression and may affect treatment efficacy, depending on the treatment method. Transverse carpal ligament thickness may be a criterion for deciding between surgical and conservative treatments based on a thickness threshold of 1.5 mm.

Surgical intervention for carpal tunnel syndrome in individuals with spinal cord injuries-patient characteristics, diagnostic considerations, and treatment outcomes

STUDY DESIGN

A retrospective chart audit.

OBJECTIVES

To characterize SCI patients with carpal tunnel syndrome (CTS) and evaluate the diagnostic rationale for surgical decision-making.

SETTING

Swiss Paraplegic Centre, Nottwil, Switzerland.

METHODS

Retrospective investigation of medical history, diagnostics, surgeries, and outcomes of surgical treatments of CTS in patients with para- and tetraplegia.

RESULTS

We identified a total of 77 surgeries for CTS in 55 patients: 16 females (25 surgeries) and 39 males (52 surgeries) with spinal cord injury. The majority (47 persons, 68 surgeries) were paraplegic (level of lesion Th2 and below); 8 persons (9 surgeries) were tetraplegic (level of lesion Th1 and above). ASIA scores in the tetraplegic group were A: 0, B: 1, C: 4, D: 3 while complete lesions predominated in the paraplegic group (A: 32, B: 4, C: 5, D: 6). Sixty-six out of 77 patients reported total relief of symptoms. Neither nerve conduction velocity nor motor amplitude correlated well with the severity of CTS. Co-morbidity and specific risk factors were rare.

CONCLUSIONS

SCI patients with CTS respond well to surgical decompression of median nerve regardless of level and type of spinal cord lesion and risk factors. Nerve conduction parameters and clinical findings can provide additional diagnostic support of CTS although nocturnal hand paresthesia, wrist pain at and after loading as well as failed conservative treatment are the main indications for surgical interventions. Based on symptomatology, clinical findings, and nerve conduction studies, we propose a decision-making tree for suggesting surgery or not.

Modification of intra-carpal tunnel pressure after Z-lengthening of the transverse carpal ligament

Background Flexor retinaculum reconstruction techniques or simply Flexor Retinaculum Z-lengthening have been proposed to preserve Flexor Retinaculum continuity after carpal tunnel release. Their effectiveness is based solely on symptom relief. There has been no analysis of the effects on intra-carpal tunnel pressure of Flexor Retinaculum-lengthening techniques. Objective was to compare intra-carpal tunnel pressure outcomes between complete division and Z-lengthening of the Retinaculum in a cadaveric model of carpal tunnel release. Methods Experimental study of carpal tunnel pressure after surgical Flexor Retinaculum modification in 10 fresh-frozen forearm and hand cadaveric specimens. The Kyphon™ Balloon Kyphoplasty system was used to measure the pressure before and after infusing 1, 2, 3, 4 and 5 ml of saline solution when untreated (Flexor Retinaculum continuity stage I), when Z-lengthened (Flexor Retinaculum continuity stage II), and after complete Flexor Retinaculum division (Flexor Retinaculum continuity stage III). Finding Intra-carpal tunnel pressure increased with larger volume of infused saline solution, although mean pressures were lower after Z lengthening or complete division of the Retinaculum than at baseline. Analysis of linear regression coefficients indicated significant differences as a function of FR continuity stage (F(2,18) = 18.38, p < 0.001), while the Bonferroni test revealed significant differences in slopes between stages I and III (p = 0.003), between stages I and II (p < 0.02), but not between stages II and III (p > 0.05). Interpretation The effectiveness of carpal tunnel release and the reduction in intra-carpal tunnel pressures obtained by Z-lengthening of the FR were similar to those observed after its complete division, while preserving FR continuity.

'INSIGHT-PRECISION': a new, mini-invasive technique for the surgical treatment of carpal tunnel syndrome

Objective

To describe a new mini-invasive surgical technique for carpal tunnel release and to present clinical findings associated with using this technique.

Methods

Patients with idiopathic carpal tunnel syndrome without prior surgical treatment, who underwent a new minimally-invasive surgical technique using a specific surgical tool-kit developed by the author, were included. Prospective data were collected, including preoperative electrodiagnostic testing. The subjective condition of all patients was evaluated pre- and postoperatively with a five-level Likert-type scale (LS) and muscular strength was tested using a JAMAR dynamometer and pinch gauge.

Results

A total of 116 patients (157 hands/cases) underwent surgery performed by the author, and were followed for a mean of 40 months (range, 6 months–7 years). Of these, preoperative electrodiagnostic testing was performed in 112 patients (96.6%). No significant complications were reported. By three months, patients reported that they were satisfied or very satisfied in 147/149 cases (98.7%; LS grade I and II). Strength recovery at three months, based on the average of four measures, was 99.17% (range, 97.43–100.97%).

Conclusions

The described technique is minimally invasive, safe and simple to perform, and provides good results.

A Clinical Study of the Modified Thread Carpal Tunnel Release

BACKGROUND

Previous studies have indicated that the thread carpal tunnel release (TCTR) is a safe and effective technique. Through a study on 11 cadaveric wrists, the TCTR procedure was modified and the needle control accuracy was improved to 0.15 to 0.2 mm, which is precise enough to preserve superficial palmar aponeurosis (SupPA), Berrettini branch, and common digital nerves. The aim of the present study was to verify the modified TCTR clinically.

METHODS

The modified TCTR was performed on 159 hands of 116 patients. The Boston Carpal Tunnel Syndrome Questionnaire was used for assessing the outcomes. Statistical analyses were used to compare the outcomes with the available data from the literature for the open and endoscopic techniques.

RESULTS

TCTR led to significant improvement in the short-term results, and the outcomes were better in long-term results compared with the open or endoscopic release. The SupPA, Berrettini branch, and common digital nerves were protected. There was no neurovascular complication for any case. Significant relief of symptoms was observed 3 to 5 hours post procedure. Most patients used their hands on the day of the procedure for simple daily activity. Patients reported their sleep quality was improved on the surgical day. Most patients with office jobs were able to return to work on postoperative day 1, and those with repetitive jobs returned to work in about 2 weeks. The statistical evidence proves that the modified TCTR procedure results in improved clinical outcomes as compared with open carpal tunnel release (CTR) and endoscopic CTR.

CONCLUSIONS

The TCTR procedure has been shown to be a safe and effective technique for CTR. The modified TCTR procedure minimizes postoperative complications, such as pillar pain, scar tenderness, or functional weakness, by avoiding unnecessary injuries to the surrounding structures around the transverse carpal ligament during the procedure.

Carpal arch and median nerve changes during radioulnar wrist compression in carpal tunnel syndrome patients

The purpose of this study was to investigate the morphological changes of the carpal arch and median nerve during the application of radiounlarly directed compressive force across the wrist in patients with carpal tunnel syndrome. Radioulnar compressive forces of 10 N and 20 N were applied at the distal level of the carpal tunnel in 10 female patients diagnosed with carpal tunnel syndrome. Immediately prior to force application and after 3 min of application, ultrasound images of the distal carpal tunnel were obtained. It was found that applying force across the wrist decreased the carpal arch width (p < 0.001) and resulted in increased carpal arch height (p < 0.01), increased carpal arch curvature (p < 0.001), and increased radial distribution of the carpal arch area (p < 0.05). It was also shown that wrist compression reduced the flattening of the median nerve, as indicated by changes in the nerve's circularity and flattening ratio (p < 0.001). This study demonstrated that the carpal arch can be non-invasively augmented by applying compressive force across the wrist, and that this strategy may decompress the median nerve providing symptom relief to patients with carpal tunnel syndrome. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1234-1240, 2016.