Superficial Radial Sensory Nerve Research Articles

De Quervain's Tenosynovitis Release With Excision of the First Dorsal Compartment: Novel Surgical Technique and a Case Series.

Incision of the dorsal side of the tendon sheath in release of De Quervain's tenosynovitis has traditionally been advocated to prevent the risk of volar tendon subluxation. We describe a novel technique of complete excision, rather than simple incision, of the first dorsal compartment tendon sheath. Over a 10-year period, 147 patients (154 wrists) underwent first dorsal compartment release using this technique of complete excision of the sheath. No postoperative immobilization is used. Patients were followed for a mean of 7.0 months. Records were assessed for any complications including reoperation, tendon subluxation, recurrence, wound complications, scar tenderness, and superficial radial sensory nerve paresthesias. There were no cases of recurrence, reoperation, or tendon subluxation after release with this technique. Postoperatively, 7 (4.5%) patients had scar tenderness and 5 (3.2%) of these patients also had superficial radial sensory nerve parasthesias, which all resolved at the time of final follow-up. Mean range of motion was 73±11 degrees of flexion and 69±10 degrees of extension. In contrast to simple incision, we propose that this technique provides a more complete release of the compartment without risk of symptomatic subluxation or bowstringing and provides a complete release of a separate extensor pollicis brevis subsheath or any concomitant retinacular cysts associated with the tendonitis. There is an immediate removal of the symptomatic swelling and visible, painful bump associated with the thickened retinaculum with this technique. Furthermore, no immobilization is required after surgery.

Clinical, Electrophysiological, and Sonographic Findings in Patients With Nerve Injury After Vessel Puncture.

This study aimed to describe the clinical, electrophysiological, and ultrasonographic findings of patients with nerve injury after vessel puncture. Data on ten patients (three males and seven females) with nerve injury after vessel puncture were reviewed. Demographic and clinical data were analyzed retrospectively. Bilateral electrophysiological studies were performed based on clinical findings. Ultrasonographic examinations were performed on both the affected and unaffected sides of the injured nerve. The nerves of nine patients were injured following vein puncture, and injury occurred following arterial sampling in one patient. Seven patients had superficial radial sensory nerve injury: five medial, one lateral, and one at both branches. One patient had injury to the dorsal ulnar cutaneous nerve, one to the lateral antebrachial cutaneous nerve, and one to the median nerve. Nerve conduction studies produced abnormal findings in 80% of patients, whereas ultrasonographic examinations produced abnormal findings in all of the patients. Spearman's coefficient for the correlation between the amplitude ratio and nerve cross-sectional area ratio was not significant, at -0.127 (95% confidence interval=-0.701 to 0.546, p=0.721). Ultrasonography supported by electrodiagnosis was found to be a useful method for identifying the lesion location and structural abnormalities of vessel-puncture-related neuropathy.

Cryoneurolysis for Digital Neuralgia in Professional Baseball Players: A Case Series

We describe a non-surgical approach to refractory digital neuralgia using cryoneurolysis in a series of 3 professional baseball players. Thumb injuries are common in baseball players and can sometimes be challenging to effectively manage. Depending on the injury, current treatments include anti-inflammatories, immobilization, physical therapy, corticosteroid injections, and/or surgery. A subset of patients, however, fail nonoperative management yet do not have a clear indication for surgery. Cryoneurolysis or cyroanalgesia is an FDA-approved form of neuromodulation, which has been used safely and effectively on a variety of peripheral nerves. The mechanism of action involves percutaneous introduction of a small probe under local anesthetic to nerve tissue using ultrasound guidance. The probe is then cooled to -88°C using nitrous oxide, which results in secondary Wallerian degeneration. Axonal and myelin regeneration occurs completely in 3-6 months. Visualization of the superficial radial sensory and ulnar digital nerve were obtained under ultrasound. The skin was prepared in sterile fashion. A 22-gauge 1-½ inch needle was then advanced with ultrasound guidance, and local anesthetic was applied. Both treatment sites were marked with skin marker. Cryoneurolysis was employed using a 5 mm tip. 60-second treatment cycles were performed at each site. Each of the cycles resulted in a 5 × 7 mm lesion visible as hypoechoic signal. All 3 players endorsed significant and prolonged relief and were able to return to an elite level of play. This manuscript is subject to all of the limitations of a case series, and larger rigorous studies are needed to illuminate causal inferences. Novel, complex technologies may also be more susceptible to placebo effect. Nonetheless, we are able to report marked efficacy and safety from cryoneurolysis of the ulnar digital nerve and the superficial radial sensory nerve in a small group of elite baseball players with refractory digital neuralgia.

Cross-sectional area reference values for high-resolution ultrasonography of the upper extremity nerves in healthy Asian adults.

In this study, multiple-site, cross-sectional area (CSA) reference values were established for major peripheral nerves, including small branches, in the upper extremity of a healthy Asian population.This study included 107 prospectively recruited age-matched, healthy subjects with a mean age of 46 years (range, 24–75 years). All subjects underwent standardized nerve conduction studies for the median, ulnar, peroneal, posterior tibial, and sural nerves. CSA was measured unilaterally at 21 sites of the median, ulnar, radial, posterior interosseous, superficial radial sensory, musculocutaneous, lateral antebrachial cutaneous, and medial antebrachial cutaneous nerves.According to their age, the subjects were assigned to the younger group (20–40 years, n = 40), the middle group (40–59 years, n = 40), and the older group (60–80 years, n = 27). The significant differences of CSA values between age groups were found only at certain sites, such as the median (wrist, P = .003), ulnar (medial epicondyle, P = .031; forearm, P = .022), radial (antecubital fossa, P = .037), and superficial radial sensory nerve (P = .028). The CSA significantly correlated with gender, height, weight, and body mass index.This study provides CSA reference values for nerves, including small sensory nerves in the upper extremity, which can be useful in the ultrasonographic investigation of various peripheral neuropathies in the upper extremity.

Effect of Fascia Penetration on Sensory Nerve Conduction in the Superficial Radial Nerve.

The aim of this study was to identify the effects of fascia penetration on superficial radial sensory nerve action potential amplitude. The penetration point (PP) at which the nerve penetrated the brachioradialis fascia and became superficial was observed using ultrasonography. The sensory nerve action potential amplitude was measured at five points: the penetration point, 2 and 4 cm proximal to the PP, and 2 and 4 cm distal to the PP. The sensory nerve action potential amplitude at the penetration point and at 2 and 4 cm distal to the PP was significantly larger than that at 2 and 4 cm proximal to the PP. The largest amplitude was obtained 2 cm distal to the PP. The sensory nerve action potential of the superficial radial nerve changes significantly around the fascia penetration point.

Superficial radial sensory neuropathy: Medial and lateral branch injury.

Superficial radial sensory nerve (SRN) injury may involve the main nerve or its distal medial or lateral branch. We investigated the utility of SRN conduction studies on the medial and lateral branches in patients with suspected SRN injury. Fifteen patients with symptoms of SRN neuropathy were studied. Their clinical and electrophysiological findings were assessed according to sensory symptom areas. Three active recording electrode positions were used: snuff box (position A); medial branch (position B); and lateral branch (position C). In 7 patients with medial area symptoms, abnormal findings were seen in position B (100%) and position A (71%). In 3 patients with medial and lateral area symptoms, abnormal findings were seen in all positions. In 5 patients with lateral symptoms, abnormal findings were seen in position C only. Nerve conduction studies for each branch of the SRN are useful in patients with suspected SRN neuropathy.

Poster 287 The Value of Combined Electrodiagnosis and Ultrasound in the Assessment of a Superficial Radial Sensory Nerve Compression from a Complex Ganglion Cyst: A Case Report

Poster 287 The Value of Combined Electrodiagnosis and Ultrasound in the Assessment of a Superficial Radial Sensory Nerve Compression from a Complex Ganglion Cyst: A Case Report

Unique Occurrence of Mucosa-Associated Lymphoid Tissue Lymphoma Disseminated to Peripheral Nerves

Lymphomatous spread to peripheral nerves is a rare but long recognized complication, most commonly involving aggressive B-cell lymphomas. A 67-year-old woman with a history of a low-grade, gastric mucosa-associated lymphoid tissue (MALT) lymphoma, which was in remission, presented with a left-sided forearm mass and numbness over the dorsolateral aspect of the thumb. Magnetic resonance imaging revealed a mass associated with the superficial radial sensory nerve in the distal forearm, which demonstrated fluorodeoxyglucose avidity on positron emission tomography. An ultrasound-guided needle biopsy was performed yielding a diagnosis of low-grade lymphoma, consistent with extranodal marginal zone lymphoma. Subsequently, she was found to have bilateral sciatic nerve involvement. This case describes the first known reported spread of MALT lymphoma to peripheral nerves in the limbs.

Treatment of Distal Radial Fractures with an Intramedullary Nail

This paper will describe the surgical technique for the treatment of unstable distal radial fractures with use of the MICRONAIL Intramedullary Distal Radius System (Wright Medical Technology, Arlington, Tennessee). The fracture must be adequately reduced and pinned prior to nail insertion. Protect the branches of the superficial radial sensory nerve at all times. Insert the nail to a depth to place the most distal screw just proximal to the radiocarpal joint line; confirm fluoroscopically that the screw does not penetrate the articular surface. Confirm that the proximal interlocking screws are bicortical for adequate fixation but are not too long. Use of a splint is followed by active and then passive range-of-motion exercises. We reported a prospective analysis of patients treated for an unstable distal radial fracture with an intramedullary nail. IndicationsContraindicationsPitfalls & Challenges.

Documenting the Density of Innervation in a Sensate Radial Forearm Flap Based on the Lateral Antebrachial Cutaneous Nerve

Sir: A left radial forearm innervated flap was elevated for a hemitongue reconstruction but was not needed. The flap, still attached by its vascular pedicle and the lateral antebrachial cutaneous nerve, was returned to the forearm. One month later, we subjected it to sensory testing to see whether (1) the flap retained normal and evenly distributed sensation (demonstrating its suitability as a sensate flap) and (2) the division of overlapping contributions from the superficial radial sensory nerve and the medial antebrachial cutaneous nerve reduced the flap's sensory acuity. The flap measured 10 × 6 cm. It lay to the radial side of the distal forearm, with its lateral border overlying the cephalic vein and its medial third lying medial to the midline of the forearm. By its position, overlapping sensory contributions from the medial antebrachial cutaneous nerve and the DRCN would be expected.1–4 A mirror image of the flap was drawn on the opposite (right) forearm. Each was divided into longitudinal and transverse thirds (Fig. 1) and tested for pain (sharp/dull), temperature (hot/cold), light pressure (Semmes-Weinstein monofilament 10-g, 5.07 strand), and static and moving two-point discrimination.Fig. 1.: Postoperative day 30: the left innervated radial forearm flap is healing satisfactorily. Its image has been marked on the contralateral (right) forearm as a control. Each is divided into nine mirror-image zones.Light pressure, vibration, hot, and cold sensation were present equally in all nine segments of both the flap and control. One-centimeter static two-point discrimination was present in all nine segments of both flap and control. Eight-millimeter static two-point discrimination was equally variable bilaterally (Fig. 2).Fig. 2.: Eight-millimeter static two-point discrimination (+, present; 0, absent).Six-millimeter moving two-point discrimination was present in all nine segments of both flap and control groups. Five-millimeter moving two-point discrimination was equally variable bilaterally (Fig. 3). Sharp-dull discrimination was present bilaterally in all segments except the flap's zone 9.Fig. 3.: Five-millimeter two-point moving discrimination (+, present; 0, absent). Six and 8 mm were present in all zones.The lateral antebrachial cutaneous nerve is the dominant sensory nerve of the lateral forearm, with overlap from the medial antebrachial cutaneous nerve and superficial radial sensory nerve.1–4 The tiny area of sensory loss when the superficial radial sensory nerve is cut suggests a fairly extensive overlap. Because this forearm flap was designed to capture the primary territory of the lateral antebrachial cutaneous nerve and include the cephalic vein, it was centered on a line running between the radial artery and the cephalic vein in the distal forearm.1 Boutros et al. stated that although the lateral antebrachial cutaneous nerve is the dominant sensory nerve of the forearm, 40 percent of the flap is unrepresented by the nerve.4 However, the flap reported by Boutros et al. had its skin paddle extending from the brachioradialis laterally to the flexor carpi ulnaris medially. Boutros et al. stated that for ideal sensation, all three sensory nerves of the forearm should be raised and anastomosed to the lingual nerve stump.4 This is unnecessary: the lateral antebrachial cutaneous nerve flap clearly carries normal sensation. Furthermore, overlapping sensory contributions from the medial antebrachial cutaneous nerve and the superficial radial sensory nerve do not summate in providing normal sensation: the flap is adequately innervated by the lateral antebrachial cutaneous nerve alone. Because the removal of nerves supplying overlapping territory results in no diminution of sensation, we must conclude that this redundancy may have some survival advantages, and that the neurons carrying sensation from overlapping areas by means of different nerves simply project onto the same relay cells in the dorsal column nuclei.1 J. Brian Boyd, M.D. Sarah Sung Kim, B.S. Joachim Granzow, M.D. Tom Liu, M.D. Division of Plastic and Reconstructive Surgery Harbor–University of California, Los Angeles Medical Center David Geffen School of Medicine at University of California, Los Angeles Los Angeles, Calif.

Superficial radial sensory nerve potentials in immune-mediated and diabetic neuropathies

Superficial radial sensory nerve potentials in immune-mediated and diabetic neuropathies

Sural/radial nerve amplitude ratio: Reference values in healthy subjects

The sural/radial nerve amplitude ratio (SRAR) has been proposed as a sensitive indicator of early-stage axonal polyneuropathy. However, previous studies did not take into account the effect of sex differences or different calculating methods. To obtain reference values and information on the variability of the SRAR in daily practice, we measured amplitudes of sural and superficial radial sensory nerve action potentials in 106 healthy adults, correlated them with epidemiological variables, and calculated the SRAR in several ways. Our results show that the SRAR is a robust measure, independent of age, weight, sex, or method of calculation. The use of bilateral measurements is recommended. The cut-off value (5th percentile) of 0.2 in these healthy subjects is much lower than found previously, especially compared to defining cut-off values by comparing patients with matched controls. Further study is needed to establish the clinical value of this SRAR in the early detection of axonal polyneuropathies.

Superficial radial sensory nerve potentials in immune-mediated and diabetic neuropathies

Objective The pattern of abnormal median-normal sural sensory nerve action potential (SNAP) is frequently found in acute/chronic inflammatory demyelinating polyneuropathy (AIDP/CIDP), whereas sural/radial SNAP amplitude ratio is sensitive to detect dying-back degeneration. To investigate whether radial SNAP and its amplitude ratio to median or sural SNAP provide additional particular patterns of sensory nerve involvement. Methods Superficial radial, median, and sural SNAPs were recorded in 63 normal subjects and in 132 patients with AIDP/CIDP ( n=22), diabetic neuropathy ( n=83), or other axonal polyneuropathy ( n=27). Median/radial and sural/radial amplitude ratios were examined. Results In normal subjects, median/radial ratio was 0.96±0.05 (mean±SEM), and sural/radial ratio was 0.50±0.03. Compared with normal controls, the median/radial ratio was lower in patients with AIDP/CIDP (0.64±0.11; P<0.001) or diabetic neuropathy (0.75±0.04; P=0.08), but similar in those with other neuropathy (0.94±0.10). The sural/radial ratio was higher in the AIDP/CIDP group (0.71±0.08; P=0.10), and lower in the diabetic (0.36±0.03; P<0.001) and other axonal neuropathy groups (0.40±0.07; P=0.08). Conclusions AIDP/CIDP is associated with a reduced median/radial ratio and increased sural/radial ratio, probably reflecting demyelination predominant in the distal nerve terminals. Diabetic neuropathy is characterized by decreases in both median/radial and sural/radial ratios, presumably due to coexistence of carpal tunnel pathology and dying-back degeneration. Significance Comparison of multiple SNAP amplitudes provides information about characteristic distribution patterns of sensory nerve involvement in peripheral neuropathies.

Slowed Conduction Velocity of the Median Sensory Nerve Across the Carpal Tunnel in Normal Adults

To examine the difference of using onset or peak latency in the segmental conduction study of the median nerve in normal adults without carpal tunnel syndrome. We investigated 60 hands of 30 young healthy adults (15 men and 15 women; mean age, 27.1 yrs; range, 18-36 yrs). We performed the mid-palm segmental conduction study using antidromic and orthodromic techniques in the median sensory nerves of the second and third digits and the onset and peak latencies of the proximal (wrist-palm) and distal (palm-digit) segments were measured. The distoproximal latency ratios were compared between onset and peak latencies and were compared with the ratios of the superficial radial sensory nerve. Distoproximal peak latency ratios in the median and superficial radial sensory nerves were always >1.0 in both the antidromic and orthodromic conduction studies. However, distoproximal onset latency ratios in the median sensory nerve were >1.0 in only 35% and 21.7% of second digits and in only 25% and 11.7% of third digits in orthodromic and antidromic studies, respectively (P < 0.05). The results of distoproximal onset latency ratios in the superficial radial sensory nerve were 93.3% in the orthodromic study and 86.7% in the antidromic study (P < 0.05). Prolongation of onset latency across the carpal tunnel during segmental conduction study of the median sensory nerve was common in healthy adults. When comparing proximal and distal segments for diagnosis of carpal tunnel syndrome, using onset latency as a diagnostic variable may cause greater reporting of false positives.

Referred Pain Pattern of the Abductor Pollicis Longus Muscle

To determine the referred pain pattern of the abductor pollicis longus muscle. Intramuscular hypertonic saline was injected into the abductor pollicis longus of 15 healthy adults to induce muscle pain. Subjects completed pain drawings depicting the pain distribution. The drawings were transferred into the Pain Chart System for analysis. Referred pain distributions were as follows: the radial aspect of the wrist (61.9%), the dorsal aspects of the third and fourth fingers (14.3%), and a combination of the two distribution patterns (23.8%). Referred pain patterns of the abductor pollicis longus resemble the C6, 7, and 8 dermatomes, the superficial radial sensory nerve distribution, and are very similar to the area of pain experienced in de Quervain's tenosynovitis. Thus, identification of the abductor pollicis longus trigger point should be considered in pain of the radial aspect of the wrist and thumb, especially when no other neurologic abnormalities or inflammatory conditions are present.

Effect of Fluidotherapy on Superficial Radial Nerve Conduction and Skin Temperature

Cross-sectional study. The purpose of this study was to examine the effects of the superficial heating modality, Fluidotherapy, on skin temperature and on sensory nerve action potential (SNAP) conduction latency and amplitude of the superficial radial nerve in healthy individuals. Fluidotherapy is a dry, superficial heating modality, which also provides tactile stimulation through the bombardment of air-fluidized cellulose particles. Previous literature has documented a direct relationship between skin temperature and neural conduction velocity; however, there is an absence of published research examining the effects of Fluidotherapy, and of tactile stimulation specifically, on neural conduction. Twenty-one subjects between the ages of 22 and 31 years (mean+/-SD, 25.5+/-0.7 years) and without prior history of diabetes, alcoholism, renal or metabolic dysfunction, current pregnancy, or heat sensitivity were invited to participate. Subjects completed an upper quarter screening exam and medical history form prior to participation. One group underwent heat (46.7 degrees C-48.9 degrees C) and tactile stimulation, a second group underwent tactile stimulation alone, while a third served as controls. Dependent variables were assessed at 3 intervals: before the intervention, immediately after the intervention, and 20 minutes after the intervention. All interventions were 20 minutes in length. A mixed 2-way analysis of variance indicated a significant interaction between time of neural conduction velocity assessment and treatment group for the dependent variables of sensory nerve action potential latency (P< .001) and skin temperature (P< .001). Appropriate post hoc tests were performed for simple effect comparisons. An inverse linear relationship existed between skin temperature and latency (r2 = .65; Pearson product coefficient, -.81). Fluidotherapy treatment, which combines the effects of heat and tactile stimulation, significantly elevated superficial skin temperature, while tactile stimulation alone and no treatment (control group) did not bring about a temperature change. As the superficial skin temperature increased, there was a concomitant decrease in the distal sensory latency of the superficial radial sensory nerve action potential. These results should be an important consideration for the clinician using superficial heating modalities.

Neural anatomy of the radial forearm flap.

Typically the lateral antebrachial cutaneous nerve alone is used to innervate the radial forearm free flap when a sensate flap is required. The authors desired, by means of fresh cadaveric microdissections and by means of local anesthetic injections in living subjects, to map the sensory nerve territories of this flap. Eight radial forearm flaps were elevated and the medial antebrachial cutaneous nerve (MABC), lateral antebrachial cutaneous nerve (LABC), and superficial radial sensory nerve (SRSN) were dissected with the aid of an operating microscope (2.5-10x) and traced to their dermal insertions. In the injection study, the MABC, LABC, and SRSN in eight forearms of 4 subjects were blocked sequentially with 2% lidocaine injections. The resulting sensory deficit from each injection was mapped on the skin and superimposed on the marked radial forearm flap territory. Distribution of the three dissected nerve regions and the sensory deficit after injection were determined by digital images and computer analysis. During flap dissections, mean nerve distributions of total flap area were as follows: LABC, 61.8% (range, 48.3-71.6%); MABC, 33.8% (range, 30.5-38.9%); and SRSN, 34.6% (range, 26.8-44.1%). After nerve block the mapped sensory areas were as follows: LABC, 62.3% (range, 44.5-88.5%); MABC, 19.6% (range, 8.0-35.8%); and SRSN, 19.5% (range, 9.9-26.3%). At least 40% of the total flap area was not innervated by the LABC as identified both by nerve dissection and sensory local anesthetic blockade. By including the LABC, MABC, and SRSN in the radial forearm flap, both the theoretical and the clinically determined useful sensory innervation of the radial forearm flap potentially would be increased.

The usefulness of minimal F-wave latency and sural/radial amplitude ratio in diabetic polyneuropathy.

The possibility of whether minimal F-wave latency and a simple ratio between the sural and superficial radial sensory response amplitudes may provide a useful electrodiagnostic test in diabetic patients was investigated in this report. To evaluate the diagnostic sensitivity of minimal F-wave latency, the Z-scores of the minimal F-wave latency, motor nerve conduction velocity (MCV), amplitude of compound muscle action potentials (CMAP), and distal latency (DL) of the median, ulnar, tibial, and peroneal nerve were compared in 37 diabetic patients. For the median, ulnar, and tibial nerves, the Z scores of the minimal F-wave latency were significantly larger than those of the MCV. In addition for all four motor nerves, the Z scores of the minimal F-wave latency were significantly larger than those for the CMAP amplitude. Furthermore, 19 subjects showing abnormal results in the standard sensory nerve conduction study had a significantly lower sural/radial amplitude ratio (SRAR), and 84% of them had an SRAR of less than 0.5. In conclusion, minimal F-wave latency and the ratio between the amplitudes of the sural and superficial radial sensory nerve action potential are sensitive measures for the detection of nerve pathology and should be considered in electrophysiologic studies of diabetic polyneuropathy.

Low-Profile Dynamic Wrist Splint

A low-profile dynamic wrist splint has been designed for use by patients who have undergone simultaneous de Quervain's release and basal joint arthroplasty. The splint allows gentle postoperative gliding of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) tendons while stabilizing the basal joint arthroplasty. Excursion of APL and EPB tendons over the basal joint area is vital to prevent adherence of the tendons or the superficial radial sensory nerve in this area. The splint is for daytime use only. A forearmbased thumb spica splint should be used at night and during high-risk activities . The splint may be placed as early as 24 hours postoperatively .