Gliding characteristics between flexor tendons and surrounding tissues in the carpal tunnel: a biomechanical cadaver study.

The purpose of this study was to investigate the gliding characteristics of flexor tendons within the carpal tunnel with varied wrist positions and tendon motion styles, which may help us to understand the relationship between carpal tunnel syndrome (CTS) and repetitive hand motion. Eight fresh human cadaveric wrists and hands were used. The peak (PGR) and mean (MGR) gliding resistance of the middle finger flexor digitorum superficialis tendon were measured with the wrist in 0, 30, and 60 degrees of flexion and extension. While moving all three fingers together, the PGR at 60 degrees flexion was significantly higher than that at 0, 30, or 60 degrees extension. While moving the middle finger alone, the PGR at 60 and 30 degrees flexion was significantly higher than the PGR at 60 degrees extension. The PGR moving the middle finger FDS alone was significantly greater than that for all three digits moving together in 0, 30, and 60 degrees flexion. Differential finger motion with wrist flexion elevated the tendon gliding resistance in the carpal tunnel, which may be relevant in considering the possible role of wrist position and activity in the etiology of CTS.     

Subjective Outcomes of Carpal Tunnel Release in Patients with Diabetes and Patients without Diabetes

Introduction  This study aims to compare the subjective outcomes of carpal tunnel surgery in the patients with diabetes and patients without diabetes, and it tries to determine the difference between insulin-dependent and noninsulin-dependent patients. Materials and Methods  This retrospective cohort study compares subjective outcomes of 35 patients with type 2 diabetes and 35 patients without diabetes who had a unilateral carpal tunnel release. None of the patients with diabetes had neuropathy. All the patients had surgery by a single surgeon with miniopen incision under local anesthesia. The patients were evaluated before surgery and 6 months after surgery using two Brigham and Women''s Carpal Tunnel Questionnaires Results  Carpal tunnel release was improved based on symptom severity scale (SSS) and functional status scale scores in patients with diabetes and nondiabetic patients. However, the mean SSS scores were higher in patients without diabetes 6 months after the surgery. Comparison between the mean SSS scores of the patients with diabetes showed higher scores in noninsulin-dependent patients. In patients with diabetes, SSS scores were positively correlated with carpal tunnel syndrome and diabetes durations. Conclusion  The outcomes of carpal tunnel release were improved in both patients with diabetes and patients without diabetes suffering from median nerve compression at the wrist. However, the duration of diabetes and its treatment can be related to the severity of the disease symptoms after the carpal tunnel releasing surgeries. In some diabetic patients, the severity of the symptoms was persistent. Level of Evidence  This is a prognostic level IV study.     

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.     

Morphologic Analysis of the Carpal Tunnel and Median Nerve Following Open and Endoscopic Carpal Tunnel Release

Background: Endoscopic carpal tunnel release (ECTR) has purported advantages over open release such as reduced intraoperative dissection and trauma and more rapid recovery. Endoscopic carpal tunnel release has been shown to have comparable outcomes to open release, but open release is considered easier and safer to perform. Previous studies have demonstrated an increase in carpal tunnel volume, regardless of the technique used. However, the mechanism by which this volumetric increase occurs has been debated. Our study will determine through magnetic resonance imaging (MRI) analysis the morphologic changes that occur in both open carpal tunnel release (OCTR) and ECTR, thereby clarifying any morphologic differences that occur as a result of the 2 operative techniques. We hypothesize that there will be no morphologic differences between the 2 techniques. Methods: This was a prospective study to compare the postoperative anatomy of both techniques with MRI. Nineteen patients with clinical and nerve conduction study–confirmed carpal tunnel syndrome underwent either open or endoscopic release. Magnetic resonance imaging was performed preoperatively and 6 months postoperatively in all patients to examine the volume of the carpal tunnel, transverse distance, anteroposterior (AP) distance, divergence of tendons, and Guyon’s canal transverse and AP distance. Results: There was no significant difference in the postoperative morphology of the carpal tunnel and median nerve between OCTR and ECTR at 6-month follow-up on MRI. Conclusion: We conclude that there are no morphologic differences in OCTR and ECTR. It is an increase in the AP dimension that appears to be responsible for the increase in the volume of the carpal tunnel.     

Predicting Carpal Bone Kinematics Using an Expanded Digital Database of Wrist Carpal Bone Anatomy and Kinematics

The wrist can be considered a 2 degrees‐of‐freedom joint with all movements reflecting the combination of flexion–extension and radial–ulnar deviation. Wrist motions are accomplished by the kinematic reduction of the 42 degrees‐of‐freedom of the individual carpal bones. While previous studies have demonstrated the minimal motion of the scaphoid and lunate as the wrist moves along the dart‐thrower's path or small relative motion between hamate‐capitate‐trapezoid, an understanding of the kinematics of the complete carpus across all wrist motions remains lacking. To address this, we assembled an open‐source database of in vivo carpal motions and developed mathematical models of the carpal kinematics as a function of wrist motion. Quadratic surfaces were trained for each of the 42‐carpal bone degrees‐of‐freedom and the goodness of fits were evaluated. Using the models, paths of wrist motion that generated minimal carpal rotations or translations were determined. Model predictions were best for flexion–extension, radial–ulnar deviation, and volar–dorsal translations for all carpal bones with R ² > 0.8, while the estimates were least effective for supination‐pronation with R ² < 0.6. The wrist path of motion's analysis indicated that the distal row of carpal bones moves rigidly together (<3° motion), along the anatomical axis of wrist motion, while the bones in the proximal row undergo minimal motion when the wrist moves in a path oblique to the main axes. The open‐source dataset along with its graphical user interface and mathematical models should facilitate clinical visualization and enable new studies of carpal kinematics and function. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2661–2670, 2019     

Wide Awake Open Carpal Tunnel Release: The Effect of Local Anesthetics in the Postoperative Outcome

Introduction  Wide awake open carpal tunnel decompression is a procedure performed under local anesthesia. This study aimed to present the effect of various local anesthetics in peri and postoperative analgesia in patients undergoing this procedure. Materials and Methods  A total of 140 patients, with 150 hands involved, underwent carpal tunnel release under local anesthesia. Patients were divided in five groups according to local anesthetic administered: lidocaine 2%, ropivacaine 0.75%, ropivacaine 0.375%, chirocaine 0.5%, and chirocaine 0.25%. Total 400 mg of gabapentin were administered to a subgroup of 10 cases from each group (50 cases totally), 12 hours before surgery. Patients were evaluated immediately, 2 weeks and 2 months after surgery according to VAS pain score, grip strength, and two-point discrimination. Results  In all patients, pain and paresthesia improved significantly postoperatively, while the use of gabapentin did not affect outcomes. Grip strength recovered and exceeded the preoperative value 2 months after surgery, without any difference between the groups. No case of infection, hematoma, or revision surgery was reported. Conclusion  Recovery after open carpal tunnel release appears to be irrelevant of the type of local anesthetic used during the procedure. Solutions of low local anesthetic concentration (lidocaine 2%, ropivacaine 0.375%, and chirocaine 0.25%) provide adequate intraoperative analgesia without affecting the postoperative course.     

Median nerve deformation in differential finger motions: ultrasonographic comparison of carpal tunnel syndrome patients and healthy controls

We investigated the median nerve deformation in the carpal tunnel in patients with carpal tunnel syndrome and controls during thumb, index finger, middle finger, and a four finger motion, using ultrasound. Both wrists of 29 asymptomatic volunteers and 29 patients with idiopathic carpal tunnel syndrome were evaluated by ultrasound. Cross‐sectional images during motion from full extension to flexion were recorded. Median nerve cross‐sectional area, perimeter, aspect ratio of the minimal enclosing rectangle, and circularity in extension and flexion positions were calculated. Additionally, a deformation index was calculated. We also calculated the intra‐rater reliability. In both controls and patients, the median nerve cross‐sectional area became significantly smaller from extension to flexion in all finger motions (p < 0.05). In flexion and extension, regardless of the specific finger motion, the median nerve deformation, circularity and the change in perimeter were all significantly greater in CTS patients than in controls (p < 0.05). We found excellent intra‐rater reliability for all measurements (ICC > 0.84). With this study we have shown that it is possible to assess the deformation of the median nerve in carpal tunnel syndrome with ultrasonography and that there is more deformation of the median nerve in carpal tunnel syndrome patients during active finger motion. These parameters might be useful in the evaluation of kinematics within the carpal tunnel, and in furthering our understanding of the biomechanics of carpal tunnel syndrome in the future. © 2011 Orthopaedic Research Society. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:643–648, 2012     

Dorsal Wrist Extrinsic Carpal Ligament Injury Exacerbates Volar Radiocarpal Instability After Intra-Articular Distal Radius Fracture

Background: Volar radiocarpal instability is often seen after loss of fixation of volar lunate facet fragments. The pathogenesis of post-traumatic volar radiocarpal instability is poorly understood. The purpose of this study was to determine if injury to the dorsal wrist extrinsic carpal ligaments contributes to volar radiocarpal instability. Methods: Six matched pairs of cadaveric upper extremities were tested using a dynamic hand testing system. In group 1, the intact wrist, the wrist with a volar lunate facet fracture, and the fractured wrist after 500 cycles of grip were tested. In group 2, in addition to the intact and fractured wrist, the fractured wrist with the dorsal extrinsic carpal ligaments cut and the fractured wrist with the dorsal extrinsic carpal ligaments cut after 500 cycles of grip were also tested. Volar-dorsal displacement of the lunate was measured from 45° wrist flexion to 45° wrist extension in 22.5° increments with the wrist flexors/extensors loaded for each condition. Results: Volar lunate translation did not significantly increase after the volar lunate facet fracture alone, and was not evident to a significant extent until the dorsal wrist extrinsic carpal ligaments were cut. Further instability of the lunate occurred after grip cycling only with the dorsal extrinsic capsular ligaments cut. Conclusions: Injury to the dorsal wrist extrinsic carpal ligaments exacerbates volar radiocarpal instability. Unrecognized dorsal sided injury may be a contributing factor to why stable fixation of volar lunate facet fragments remains problematic after volar plating of intra-articular distal radius fractures with displaced volar lunate facet fragments.     

Carpal arch alteration after carpal tunnel release

A retrospective clinical study quantitated postoperative widening of the transverse carpal arch after carpal tunnel release in a group of 50 patients. The relationship of this widening with postoperative pain, forearm circumference, grip strength, and wrist range of motion was evaluated. Mean widening of the transverse carpal arch after carpal tunnel release is 10.4% or 2.7 mm. A direct relationship exists between widening of the transverse carpal arch and loss of grip strength. Residual pain, forearm circumference, and wrist range of motion are not related to widening of the transverse carpal arch.     

Carpal tunnel syndrome in paraplegic patients

Thirty-eight (49 per cent) of seventy-seven paraplegic patients whose level of injury was at or caudad to the second thoracic vertebra were found to have signs and symptoms of carpal tunnel syndrome. The prevalence of carpal tunnel syndrome was found to increase with the length of time after the injury. In the eighteen patients in whom manometric studies were done, the carpal tunnel pressures when the wrist was in the neutral position were higher than those that have been reported in non-paraplegic patients who did not have carpal tunnel syndrome but were lower than the values in non-paraplegic patients who did have the syndrome. When the wrist was in flexion, the pressures were similar to the values that have been reported for non-paraplegic patients. However, in the paraplegic patients, regardless of whether or not they had carpal tunnel syndrome, the pressures that developed when the wrist was in extension were significantly higher than those in non-paraplegic patients, regardless of whether or not they had carpal tunnel syndrome. Most of the activities of daily living of paraplegic patients, including the maneuver to relieve ischial pressure that consists of arising from the seated position using the extended arms, are performed with the wrists locked in maximum extension. The pressure that develops in the carpal canal during this forced extension of the wrist, probably combined with the repetitive trauma to the volar aspect of the extended wrist while propelling a wheelchair, contributes to the high frequency with which carpal tunnel syndrome is found in paraplegic patients.     

Ultrasound assessment of the effectiveness of carpal tunnel release on median nerve deformation

To assess the biomechanical effect of carpal tunnel release (CTR), we evaluated the deformation and displacement patterns of the median nerve before and after CTR in carpal tunnel syndrome (CTS) patients. Sixteen wrists of 14 idiopathic CTS patients who had open CTR and 26 wrists of 13 asymptomatic volunteers were evaluated by ultrasound. Cross‐sectional images of the carpal tunnel during motion from full finger extension to flexion were recorded. The area, perimeter, aspect ratio of a minimum enclosing rectangle, and circularity of the median nerve were measured in finger extension and flexion positions. Deformation indices, determined by the flexion–extension ratio for each parameter, were compared before and after CTR. After CTR, the deformation indices of perimeter and circularity became significantly larger and the aspect ratio became significantly smaller than those before CTR (p < 0.05). Those differences were more obvious when comparing the values between the patients before CTR and the controls. Since the deformation indices after CTR are similar to the patterns of normal subjects, the surrounding structures and environment of the median nerve may be normalized upon CTR. This may be a way to tell how the median nerves recover after CTR. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:726–730, 2015.     

On Resection of the Knee

In 16 patients, where the diagnosis carpal tunnel syndrome was electrophysiologi-cally confirmed, the pressure between the median nerve and the carpal ligament was measured peroperatively.

At rest the pressure was 18-64 mmHg, mean 31 mmHg. Passive volar and dorsal wrist flexion increased the pressure about three times. Isometric or isotonic maximal contractions of wrist and finger muscles, elicited by tetanic nerve stimulation increased the pressure to three to six times the resting value. These high pressures may be one of the causes of the nerve lesion in the carpal tunnel syndrome.     

Median nerve deformation and displacement in the carpal tunnel during index finger and thumb motion

The purpose of this study was to investigate the deformation and displacement of the normal median nerve in the carpal tunnel during index finger and thumb motion, using ultrasound. Thirty wrists from 15 asymptomatic volunteers were evaluated. Cross‐sectional images during motion from full extension to flexion of the index finger and thumb were recorded. On the initial and final frames, the median nerve, flexor pollicis longus (FPL), and index finger flexor digitorum superficialis (FDS) tendons were outlined. Coordinate data were recorded and median nerve cross‐sectional area, perimeter, aspect ratio of the minimal‐enclosing rectangle, and circularity in extension and flexion positions were calculated. During index finger flexion, the tendon moves volarly while the nerve moves radially. With thumb flexion, the tendon moves volarly, but the median nerve moves toward the ulnar side. In both motions, the area and perimeter of the median nerve in flexion were smaller than in extension. Thus, during index finger or thumb flexion, the median nerve in a healthy human subject shifts away from the index finger FDS and FPL tendons while being compressed between the tendons and the flexor retinaculum in the carpal tunnel. We are planning to compare these data with measurements in patients with carpal tunnel syndrome (CTS) and believe that these parameters may be useful tools for the assessment of CTS and carpal tunnel mechanics with ultrasound in the future. Published by Wiley Periodicals, Inc. J Orthop Res 28:1387–1390, 2010     

Postoperative changes of carpal canal pressure in carpal tunnel syndrome: a prospective study with follow-up of 1 year

Carpal canal pressures were measured in 103 patients with idiopathic carpal tunnel syndrome, before and after open release, with a postoperative follow-up of 1 year. Twenty-five normal subjects were used as controls. Pressures were measured with the wrists in three positions: neutral, full passive flexion and full passive extension. At each wrist position, the mean pre-operative pressures in the study group were significantly higher than in the control group. In both groups, the pressures were maximal with full passive extension and minimal in the neutral wrist position. Immediately after surgical release, there was a marked decrease of the carpal canal pressures. However, during the second postoperative month, there was a significant increase of the pressures at each wrist position, although these were still within the normal control range. This rise in pressures persisted to 12 months. These findings suggest that the carpal ligament reconstitutes by normal scar formation, but with lengthening such that the volume of the carpal canal is enlarged, so preventing a rise in pressure with return of the pre-operative problem.     

Median nerve deformation and displacement in the carpal tunnel during finger motion

The objective of this study was to evaluate the correlations between deformation and displacement of median nerve and flexor tendons during finger motion in the carpal tunnel for both carpal tunnel syndrome (CTS) patients and healthy controls. Sixty‐two wrists of 31 asymptomatic volunteers and fifty‐one wrists of 28 idiopathic CTS patients were evaluated by ultrasound. The displacement of the median nerve and the middle finger flexor digitorum superficialis (FDS) tendon, as well as area, perimeter, aspect ratio of a minimum enclosing rectangle, and circularity of the median nerve were measured in finger extension and flexion positions. Deformation indices were defined as the ratios of indices in finger extension and flexion positions. The correlations between displacement and deformation indices were evaluated. There were significant correlations between nerve palmar–dorsal displacement and deformation indices (p < 0.05). The aspect ratio deformation index showed the strongest correlation to palmar–dorsal displacement of the nerve (?0.572, p < 0.01). This study showed that there is a relationship between median nerve deformation indices and nerve palmar–dorsal displacement in the carpal tunnel. Since the highest correlations were between palmar–dorsal nerve displacement direction and aspect ratio deformation index, these parameters may be helpful to understand the pathophysiology of CTS. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1876–1880, 2013

     

Relative motion between the flexor digitorum superficialis tendon and paratenon in zone V increases with wrist flexion angle

Carpal tunnel syndrome is characterized by non‐inflammatory fibrosis of the subsynovial connective tissue (SSCT), a paratenon‐like structure inside the carpal tunnel. This pathology suggests repetitive and/or excessive shear forces are involved in injury development. We assessed relative motion between the flexor digitorum superficialis (FDS) tendon and adjacent paratenon in Zone V using colour Doppler imaging as 16 healthy participants completed three long finger movements (metacarpophalangeal joint flexion, proximal and distal interphalangeal joint flexion, full finger flexion) in three wrist postures (30° extension, 0°, 30° flexion). While the type of finger movement did not affect tendon‐paratenon relative motion, we found a significant main effect of wrist posture (p < 0.001). Relative displacement between the FDS tendon and paratenon (as a percentage of tendon displacement) increased from 27.2% (95%CI = 24.8–29.5%) in 30° wrist extension to 39.9% (95%CI = 37.3–42.4%) in 30° wrist flexion. Optical motion capture confirmed that wrist posture did not affect metacarpophalangeal joint range of motion (p = 0.265) or proximal interphalangeal joint range of motion (p = 0.582). These results indicate that relative motion increased due to paratenon strain when the wrist was flexed. While our findings agree with previous cadaveric research in wrist flexion, we found that relative displacement decreased in 30° wrist extension (compared to 0°). These results differ from cadaveric research, possibly due to challenges maintaining anatomic fidelity of the viscoelastic paratenon tissue in vitro. Overall, our study suggests a greater susceptibility to shear injury during repetitive finger movements, particularly when the wrist is flexed. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1248–1255, 2016.     

Carpal tunnel and transverse carpal ligament stiffness with changes in wrist posture and indenter size

This study investigated the effects of loading and posture on mechanical properties of the transverse carpal ligament (TCL). Ten fresh‐frozen cadaver arms were dissected to expose the TCL and positioned in the load frame of a servo‐hydraulic testing machine, equipped with a load cell and custom made indenters. Four cylindrical indenters (5, 10, 20, and 35 mm) loaded the TCL in three wrist postures (30° extension, neutral and 30° flexion). Three loading cycles with a peak force of 50 N were applied at 5 N/s for each condition. The flexed wrist posture had significantly greater TCL stiffness (40.0 ± 3.3 N/mm) than the neutral (35.9 ± 3.5 N/mm, p = 0.045) and extended postures (34.9 ± 2.8 N/mm, p = 0.025). TCL stiffness using the 10 and 20 mm indenters was larger than the 5 mm indenter. Stiffness was greatest with the 20 mm indenter, which had the greatest indenter contact area on the TCL. The 35 mm indenter covered the carpal bones, compressed the carpal tunnel and produced the lowest stiffness. The complexity of the TCL makes it an important part of the carpal tunnel and the mechanical properties found are essential to understanding mechanisms of carpal tunnel syndrome. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1682–1687, 2011     

小切口治疗腕管综合征14例报告

Objective　To introduce the technique of carpal tunnel release by small incision,and evaluate its outcome in the treatment of carpal tunnel syndrome.Methods　This method was applied in the operations of 14 cases of carpal tunnel syndrome.An incision 1.5 cm in length was made at the level of the proximal transverse wrist crease ulnar to the palmaris longus tendon.The proximal margin of the transverse carpal ligament was visualized and the ligament was cut subcutaneously under direct vision.The flexor digitorum tendons were retracted and the edematous synovium excised.Results　Follow - up of the patients 2 weeks postoperatively showed that the symptoms of numbess and pain disappeared in all 14 cases.Normal 2 - PD in the pulp of the thumb,index finger and long finger was ＜ 4 mm.One year after the operation,muscle atrophy in 5 patients who sustained preoperative thenar muscle atrophy was greatly improved with recovery of normal opponens function of the thumb.No pillar pain and injury of the ulnar nerve and superficial palmar arch was found.Conclusion　Carpal tunnel release under direct vision through a small incision is a new and effective surgical procedure.     

Pressure–morphology relationship of a released carpal tunnel

We investigated morphological changes of a released carpal tunnel in response to variations of carpal tunnel pressure. Pressure within the carpal tunnel is known to be elevated in patients with carpal tunnel syndrome and dependent on wrist posture. Previously, increased carpal tunnel pressure was shown to affect the morphology of the carpal tunnel with an intact transverse carpal ligament (TCL). However, the pressure–morphology relationship of the carpal tunnel after release of the TCL has not been investigated. Carpal tunnel release (CTR) was performed endoscopically on cadaveric hands and the carpal tunnel pressure was dynamically increased from 10 to 120 mmHg. Simultaneously, carpal tunnel cross‐sectional images were captured by an ultrasound system, and pressure measurements were recorded by a pressure transducer. Carpal tunnel pressure significantly affected carpal arch area (p < 0.001), with an increase of >62 mm² at 120 mmHg. Carpal arch height, length, and width also significantly changed with carpal tunnel pressure (p < 0.05). As carpal tunnel pressure increased, carpal arch height and length increased, but the carpal arch width decreased. Analyses of the pressure–morphology relationship for a released carpal tunnel revealed a nine times greater compliance than that previously reported for a carpal tunnel with an intact TCL. This change of structural properties as a result of transecting the TCL helps explain the reduction of carpal tunnel pressure and relief of symptoms for patients after CTR surgery. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 616–620, 2013     

RETRACTED ARTICLE: Carpal tunnel syndrome in patients who are receiving long-term renal hemodialysis

Introduction The development of a carpal tunnel syndrome has become an increasingly recognized problem in patients who are treated by long-term hemodialysis. Arteriovenous fistula has been identified as one of the possible cause for the development of carpal tunnel syndrome. Materials and methods Wrists of 558 hemodialysis patients who had fistula at least 1 year served as the case group and the other intact wrists of the same patients served as the control group. Carpal tunnel syndrome was diagnosed clinically; however, 232 random patients underwent electrodiagnostic studies the day after hemodialysis. Results In 170 (30.5%) wrists with arteriovenous fistula developed carpal tunnel syndrome versus 68 (12.2%) in the contralateral wrist. Three patients had a concurrent diagnosed radial steal syndrome. In all three wrists that had radial steal syndrome developed carpal tunnel syndrome. There was a correlation, however, between the development of the carpal tunnel syndrome, and the side of the longest vascular access. Contrary to the clinical assessment, electrodiagnostic studies did not indicate any significant association between the frequency of carpal tunnel syndrome and arteriovenous fistula or its duration. Conclusion Hemodialysis patients are at considerable risk of developing carpal tunnel syndrome in the wrist with an arteriovenous fistula. Close observation and routine clinical examination is mandatory to prevent further problems.