The Management of Cubital Tunnel Syndrome

A novel classification of intraoperative ulnar nerve instability to aid transposition surgery

HYPOTHESIS

The purpose of this study was to compare inter- and intraobserver agreement of a novel intraoperative subluxation classification for patients undergoing ulnar nerve surgery at the elbow. We hypothesize there will be strong inter- and intraobserver agreement of the 4-category classification system, and reviewers will have substantial confidence while reviewing the classification system.

METHODS

Four blinded fellowship-trained orthopedic hand surgeons reviewed 25 videos in total on 2 separate viewings, 21 days apart. Variables collected were ulnar subluxation classification (A, B, C, or D) and a confidence metric. Subsequent to primary data collection, classification grading was stratified into A/B or C/D subgroups for further analysis. Cohen κ scores were used to evaluate all variables collected in this study. The interpretation of κ scores included ≤0.0 as no agreement, 0.01-0.20 as none to slight, 0.21-0.40 as fair, 0.41-0.60 as moderate, 0.61-0.80 as substantial, and 0.81-1.0 as almost perfect agreement.

RESULTS

Interobserver agreement of subluxation classification as a 4-category scale demonstrated a moderate agreement on first viewing, second viewing, and when both viewings were combined (κ = 0.51, 0.51, and 0.51 respectively). Seventy-five percent (3 of 4) of reviewers had moderate intraobserver agreement for ulnar nerve subluxation classification, whereas 1 reviewer had substantial intraobserver classification (κ = 0.72). Overall, there was high confidence in 65% of classification scores in the second round of viewing, which improved from 58% in the first viewing round. When ulnar subluxation classification selections were regrouped into classes A/B or C/D, 100% of reviewers had substantial interobserver (κ = 0.74-0.75) and substantial to almost perfect intraobserver (κ = 0.71-0.91) agreement.

CONCLUSIONS

The 4-category classification was reproducible within and between reviewers. Agreement appeared to increase when simplifying the classification to 2 categories, which may provide guidance to surgical decision making. The validation of a reproducible classification scheme for intraoperative ulnar subluxation may aid with decision making and further postoperative outcomes research.

Anterior transposition and positioning via helix sling method in cubital tunnel syndrome: An open-label, retrospective trial of maximum 5-year follow-up

Background

Ulnar nerve transposition is used for cubital tunnel syndrome (CuTS) with nerve instability. The aim is to report a modified technique for ulnar nerve transposition using medial intermuscular septum and Osborne's ligament as a double-strand helix sling to recreate a sliding channel for the ulnar nerve and the functional outcomes at follow-ups.

Methods

Twenty-five patients with persistent CuTS underwent nerve release and subcutaneous transposition from January 2017 to January 2022 in our institute. Among them, 9 patients were excluded due to incomplete medical records, lack of follow-up history, or bilateral limb numbness. The medial intermuscular septum with one end attached was excised to rebuild a tension-free double-strand helix sling by anchoring at the residue of Osborne's ligament. The modified Mc-Gowan classification was applied to evaluate the disease severity preoperatively. The quick disability of arm and shoulder and hand (quickDASH) questionnaire and visual analogue scale (VAS) scores were used to evaluate pre- and postoperative symptoms. Ultrasound imaging was utilized for nerve structure evaluation before surgery and at follow-ups.

Results

Sixteen out of twenty-five patients received follow-ups postoperatively (ranging from 9 to 69 months, 36 months in average). No findings indicated subluxation of ulnar nerve or recompression by ultrasound imaging examination. According to quickDASH and VAS scores and physical examination, 14 out of 16 patients showed postoperative improvement in symptoms and function at final follow-ups.

Interpretation

In this modified technique, the medial intermuscular septum and Osborne's ligament can create tension-free helix sling for stable and smooth sliding and preventing subluxation after nerve transposition, which is highly effective and safe for CuTS treatment.

Post-traumatic recurrent ulnar nerve dislocation at the elbow: a rare case report

Introduction and importance

Several authors have also made reference to a less prevalent condition known in elbow as ulnar nerve subluxation. However, this particular condition tends to manifest primarily in young individuals who engage in professional sports or activities involving extensive use of the forearm. A more severe form of ulnar nerve subluxation, which is ulnar nerve dislocation, gives rise to a characteristic dislocation and relocation of the nerve at the elbow during flexion and extension of the forearm. Due to the rarity of this condition in clinical settings and its predominant occurrence as subluxation in younger patients, there are instances where traumatic ulnar nerve dislocation can be overlooked and misdiagnosed with two commonly encountered pathological conditions as ulnar nerve entrapment or medial epicondylitis.

Case presentation

The authors present a 51-year-old male with chronic pain when moving his right forearm following a fall that caused a direct force injury to his elbow. The patient was misdiagnosed and treated as medial epicondylitis and early-stage ulnar nerve entrapment. However, the symptoms did not improve for a long time. The authors performed the ulnar nerve anterior transposition surgery using the subcutaneous transposition technique and the result is very good without any pain.

Clinical discussion

The ulnar nerve can naturally be subluxed or dislocated if Osborne's ligament is loose or when there are anatomical variations in the medial epicondyle. In some case, this ligament can be ruptured by trauma. The symptoms of ulnar instability are caused by friction neuritis. Dynamic ultrasound of the ulnar nerve in two positions show clearly this condition.

Conclusion

Post-traumatic ulnar nerve dislocation is a rare condition, and the recurrent characteristic of it leads to neuritis or neuropathy. The condition can be overlooked or misdiagnosed as medial epicondylitis or early-stage ulnar nerve entrapment. The nerve transposition surgery will give good result.

Ulnar Nerve Compression at the Elbow Secondary to Intramuscular Lipoma of the Flexor Carpi Ulnaris: A Case Report

CASE

A 62-year-old right-hand-dominant woman presented with 1 year of persistent radiating pain, weakness, and paresthesias in her left forearm and hand. Electromyography findings were significant for ulnar neuropathy distal to the branch innervating the flexor carpi ulnaris (FCU), without superimposed cervical radiculopathy or other focal entrapment neuropathy. During open ulnar nerve neurolysis, an intramuscular lipoma was encountered within the FCU. Lipoma excision and cubital tunnel release with ulnar nerve transposition were performed with complete relief of neuropraxia.

CONCLUSION

We demonstrate full neurologic recovery after intramuscular lipoma excision and cubital tunnel release. Although rare, anomalous anatomy and tissue overgrowth should remain on the differential for patients presenting with atypical neuropraxia.

Modern Treatment of Cubital Tunnel Syndrome: Evidence and Controversy

Cubital tunnel syndrome is the second most common peripheral mononeuropathy in the upper extremity. However, the diagnosis and treatment of cubital tunnel syndrome remains controversial without a standard algorithm. Although diagnosis can often be made from the patient's history and physical examination alone, electrodiagnostic studies, ultrasound, computed tomography (CT), and magnetic resonance image (MRI) can also be useful in diagnosing the disease and selecting the most appropriate treatment option. Treatment options include conservative nonoperative techniques as well as various surgical options, including in situ decompression with or without transposition, medial epicondylectomy, and nerve transfer in advanced disease. The purpose of this review is to summarize the most up-to-date literature regarding cubital tunnel syndrome and propose a treatment algorithm to provide clarity about the challenges of treating this complex patient population.

A complete analysis of the surgical treatment for cubital tunnel syndrome: an umbrella review

BACKGROUND

Numerous original studies have been presented regarding various surgical treatments for cubital tunnel syndrome (CubTS). The results of these analyses regarding the different surgical treatments for CubTS frequently differ and, in some cases, contradict each other, creating confusion. Therefore, our umbrella review aimed to summarize the evidence from meta-analyses and systematic reviews regarding the surgical treatments of CubTS, and along with the new, more detailed outcomes, provide an evidence-based tool for surgeons performing these procedures.

MATERIALS AND METHODS

To perform this umbrella review, a systematic search was conducted for meta-analyses investigating CubTS in PubMed, Scopus, Embase, Web of Science, Google Scholar, Cochrane Library, BIOSIS, and EBSCO medical databases.

RESULTS

Detailed comparison of surgical outcomes, such as clinical improvement, complications, or reoperation rates, of different treatment methods for CubTS was performed. New risk ratios in all categories were established based on all of the primary studies available in the literature.

DISCUSSION

The goal of the present umbrella review was to gather and summarize all data about the surgical treatments for CubTS in the available literature and provide new outcomes and an evidence-based tool for surgeons performing these procedures. Each comparison of the surgical techniques has been discussed, and the present study's results were compared with the outcomes of the previous studies.

Avive Soft Tissue Membrane Improves Outcomes of Revision Upper-extremity Nerve Decompression Surgery

Revision nerve decompression remains a challenge for surgeons. Avive Soft Tissue Membrane is processed human umbilical cord membrane that may reduce inflammation and scarring, thereby improving tissue gliding. Although synthetic conduits have been reported in revision nerve decompression, the use of Avive has not.

Methods

Prospective study of revision nerve decompression with Avive application. VAS pain, two-point discrimination, Semmes-Weinstein, pinch and grip strength, range of motion, Quick Disability of Arm, Shoulder & Hand (QuickDASH), and satisfaction were recorded. Using a propensity-matched cohort, VAS pain and satisfaction were retrospectively collected to compare with cohort outcomes.

Results

In the Avive cohort, 77 patients (97 nerves) were included. Mean follow-up was 9.0 months. Avive was applied to the median nerve in 47.4%, ulnar nerve in 39.2%, and radial nerve in 13.4%. VAS pain was 4.5 preoperatively and 1.3 postoperatively. S4 sensory recovery was achieved in 58% of patients, S3+ in 33%, S3 in 7%, S0 in 2%, and improvement from baseline in 87%. Strength improved in 92%. Mean total active motion was 94.8%. Mean QuickDASH score was 36.1, and 96% reported improved or resolved symptoms. Preoperative pain was not significantly different between Avive cohort and controls (P = 0.618). Postoperative pain was significantly lower in cohort patients (1.3 ± 2.2 versus 2.7 ± 3.0, P = 0.001). In the Avive cohort, more had improved or resolved symptoms (P < 0.0001). Clinically important improvement in pain was reported in 64.9% of Avive group patients versus 40.8% of controls (P = 0.002).

Conclusion

Avive contributes to improved outcomes in revision nerve decompression.

Conservative Treatment of Ulnar Nerve Compression at the Elbow: A Systematic Review and Meta-Analysis

Background  The clinical results of conservative treatment options for ulnar compression at the elbow have not been clearly determined. The aim of this review was to evaluate available conservative treatment options and their effectiveness for ulnar nerve compression at the elbow. Methods  In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, a systematic review and meta-analysis of studies was performed. Literature search was performed using Ovid MEDLINE, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL). Results  Of the 1,079 retrieved studies, 20 were eligible for analysis and included 687 cases of ulnar neuropathy at the elbow. Improvement of symptoms was reported in 54% of the cases receiving a steroid/lidocaine injection (95% confidence interval [CI], 41-67) and in 89% of the cases using a splint device (95% CI, 69-99). Conclusions  Conservative management seems to be effective. Both lidocaine/steroid injections and splint devices gave a statistically significant improvement of symptoms and are suitable options for patients who refuse an operative procedure or need a bridge to their surgery. Splinting is preferred over injections, as it shows a higher rate of improvement.

Intraneural or extraneural ganglion cysts as a cause of cubital tunnel syndrome: A retrospective observational study

Purpose

Cubital tunnel syndrome caused by ganglion cysts has rarely been reported. The purpose of this study was to evaluate the surgical treatment outcomes of a patient diagnosed with cubital tunnel syndrome caused by intraneural or extraneural cysts and to summarize our experience.

Method

In total, 34 patients were evaluated retrospectively from January 2011 to January 2020 with a follow-up of more than 24 months. Preoperative data, such as demographic data, clinical symptoms, physical examination findings, and laboratory tests, were all recorded and pre-operative and post-operative data were compared. The function was evaluated by the modified Bishop scoring system and the McGowan grade at the last follow-up.

Results

Improvement of interosseous muscle strength, the Visual Analog Scale (VAS), 2-point discrimination (2-PD), electromyogram (EMG) result, Wartenberg sign, claw hand, and weakness could be clearly observed in all patients. Extraneural cysts were completely removed and the pedicles of the cysts were ligated. Intraneural cysts were incised and drained, and part of their cyst walls were removed using a microsurgical technique. All patients underwent anterior subcutaneous transposition (AST). At the last follow-up, McGowan's (0-IIa) grade increased from seven patients (20.6%) preoperatively to 27 patients (79.4%); the excellent and good rate according to the modified Bishop scoring system was 82.4% (28 patients), and all patients had no symptoms of recurrence after surgery.

Conclusion

The treatment of cubital tunnel syndrome caused by intraneural or extraneural cysts achieved good long-term results through extraneural cyst resection or intraneural cyst incision and drainage combined with subcutaneous transposition. Early diagnosis and surgical treatment are essential for the patient's postoperative recovery.

Wound Dehiscence Following Cubital Tunnel Surgery

PURPOSE

Cubital tunnel syndrome is the second most common upper-extremity compressive neuropathy, and persistent symptoms can necessitate operative treatment. Surgical options include simple decompression and ulnar nerve transposition. The cause of wound dehiscence after surgery is not well known, and the factors leading to the development of these complications have not been previously described.

METHODS

Patients undergoing ulnar nerve surgery from January 1, 2016, to December 31, 2019, were retrospectively evaluated for the development of wound dehiscence within 3 months of surgery. There were 295 patients identified who underwent transposition and 1,106 patients who underwent simple decompression. Patient demographics and past medical history were collected to evaluate the risk factors for the development of wound dehiscence.

RESULTS

The overall rate of wound dehiscence following surgery was 2.5%. In the simple decompression group, the rate of wound dehiscence was 2.7% (30/1,106), which occurred a mean of 21 days (range, 2-57 days) following surgery. In the transposition group, the rate of wound dehiscence was 1.7% (5/295), which occurred a mean of 20 days (range, 12-32 days) following surgery. The difference in rates of dehiscence between the decompression and transposition groups was not significant. Five patients in the simple decompression group and 1 patient in the transposition group required a secondary surgery for closure of the wound. Age, body mass index, smoking status, and medical comorbidities were not found to contribute to the development of wound dehiscence.

CONCLUSIONS

Wound dehiscence can occur following both simple decompression and transposition, even after postoperative evaluation demonstrates a healed wound. Surgeons should be aware of this possibility and specifically counsel patients about remaining cautious with, and protective of, their wound for several weeks after surgery. Dehiscence may be related to suboptimal vascularity in the soft tissue envelope in the posteromedial elbow. When it occurs, dehiscence can generally be treated by allowing healing by secondary intention.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

A Cadaveric Study of Thread Cubital Tunnel Release with Newly Developed Threads

Objective

The percutaneous thread transection technique is a surgical dissecting method using a dissecting thread inserted through a needle under ultrasound guidance without skin incision. As the new dissecting threads were developed domestically, this cadaver study was conducted to compare the effectiveness and safety between the new threads (ultra V sswire and smartwire-01) and a pre-existing commercial dissecting thread (loop & shear) by demonstrating a modified looped thread cubital tunnel release.

Methods

The percutaneous cubital tunnel release procedure was performed on 29 fresh cadaveric upper extremities. The preexisting commercial thread was used in 5 upper extremities. The two newly developed threads were used in 24 upper extremities. Two practitioners performed the procedures separately. After the modified looped thread cubital release, anatomical and histological analyses were performed by a blinded anatomist. The presence of the dissected cubital tunnel and damaged adjacent soft tissue was assessed.

Results

Out of the 29 cadaveric upper extremities, 27 specimens showed complete dissection of the Osborne ligament and the proximal fascia of the flexor carpi ulnaris muscle. One specimen was incompletely dissected in each of the ultra V sswire and smartwire-01 groups. There were no injuries of adjacent structures including the ulnar nerve, ulnar artery, medial antebrachial cutaneous nerve, or flexor tendon with either the commercial thread or the newly developed threads. The anatomical analysis revealed clear and sharp incisional margins of the cubital tunnel in the Smartwire-01 and loop & shear groups. All three kinds of threads maintained proper linear elasticity for easy handling during the procedure. The smartwire-01 provided higher visibility in ultrasound than the other threads.

Conclusion

The newly developed threads were effective and safe for use in the thread cubital tunnel release procedure.

Angiosomes of the Ulnar Nerve at the Elbow: A Cadaver Trial Using Contrast-Enhanced Ultrasound

Three major arteries supplying the ulnar nerve in the cubital tunnel are commonly known. However, their vascular territories (angiosomes) have not been described yet. Contrast-enhanced ultrasound was used to identify the angiosomes of posterior ulnar recurrent artery, inferior ulnar collateral artery and superior ulnar collateral artery in 20 fresh, non-frozen human body donors. The arteries were cannulated, and physiologic blood flow was simulated. Contrast agent was applied in each vessel in a randomized sequence, and the length of the contrast-enhancing ulnar nerve segment was measured by a radiologist blinded to the sequence. The angiosome of the posterior ulnar recurrent artery overlaps both other angiosomes. It fully covers the cubital tunnel in 63.6% of specimens. In addition, collateral flow via nerve and muscle branches of the arterial anastomotic network around the elbow (rete articulare cubiti) partly maintains the intra-neural blood flow in the absence of a vascular pedicle. The posterior ulnar recurrent artery is the dominant nutrient vessel of the ulnar nerve in the cubital tunnel. A potential watershed zone exists proximal to the Osborne ligament. Knowledge of these angiosomes may advance surgery of the ulnar nerve in the cubital tunnel.

Patient Perspectives on the Cost of Hand Surgery

BACKGROUND

Health-care expenditures in the U.S. are continually rising, prompting providers, patients, and payers to search for solutions to reduce costs while maintaining quality. The present study seeks to define the out-of-pocket price that patients undergoing hand surgery are willing to pay, and also queries the potential cost-cutting measures that patients are most and least comfortable with. We hypothesized that respondents would be less accepting of higher out-of-pocket costs.

METHODS

A survey was developed and distributed to paid, anonymous respondents through Amazon Mechanical Turk. The survey introduced 3 procedures: carpal tunnel release, cubital tunnel release, and open reduction and internal fixation of a distal radial fracture. Respondents were randomized to 1 of 5 out-of-pocket price options for each procedure and asked if they would pay that price. Respondents were then presented with various cost-saving methods and asked to select the options that made them most uncomfortable, even if those would save them out-of-pocket costs.

RESULTS

There were 1,408 respondents with a mean age of 37 years (range, 18 to 74 years). Nearly 80% of respondents were willing to pay for all 3 of the procedures regardless of which price they were presented. Carpal tunnel release was the most price-sensitive, with rejection rates of 17% at the highest price ($3,000) and 6% at the lowest ($250). Open reduction and internal fixation was the least price-sensitive, with rejection rates of 11% and 6% at the highest and lowest price, respectively. The use of older-generation implants was the least acceptable cost-cutting measure, at 50% of respondents.

CONCLUSIONS

The present study showed that most patients are willing to pay a considerable amount of money out of pocket for hand surgery after the condition, treatment, and outcomes are explained to them. Furthermore, respondents are hesitant to sacrifice advanced technology despite increased costs.

Compression Neuropathies of the Upper Extremity: A Review

Compressive neuropathies of the forearm are common and involve structures innervated by the median, ulnar, and radial nerves. A thorough patient history, occupational history, and physical examination can aid diagnosis. Electromyography, X-ray, and Magnetic Resonance Imaging may prove useful in select syndromes. Generally, first line therapy of all compressive neuropathies consists of activity modification, rest, splinting, and non-steroidal anti-inflammatory drugs. Many patients experience improvement with conservative measures. For those lacking adequate response, steroid injections may improve symptoms. Surgical release is the last line therapy and has varied outcomes depending on the compression. Carpal Tunnel syndrome (CTS) is the most common, followed by ulnar tunnel syndrome. Open and endoscopic CTS release appear to have similar outcomes. Endoscopic release appears to incur decreased cost baring a low rate of complications, although this is debated in the literature. Additional syndromes of median nerve compression include pronator syndrome (PS), anterior interosseous syndrome, and ligament of Struthers syndrome. Ulnar nerve compressive neuropathies include cubital tunnel syndrome and Guyon’s canal. Radial nerve compressive neuropathies include radial tunnel syndrome and Wartenberg’s syndrome. The goal of this review is to provide all clinicians with guidance on diagnosis and treatment of commonly encountered compressive neuropathies of the forearm.

Cubital tunnel perfusion in different postures-An anatomical investigation

Introduction/Aims

For cubital tunnel syndrome, the avoidance of predisposing arm positions and the use of elbow splints are common conservative treatment options. The rationale is to prevent excessive stretching and compression of the nerve in the cubital tunnel, as this mechanical stress impedes intraneural perfusion. Data regarding those upper extremity postures to avoid, or whether elbow flexion alone is detrimental, are inconsistent. This study aimed to assess perfusion and size changes of the cubital tunnel during different postures in an experimental cadaver setup.

Methods

Axillary arteries in 30 upper extremities of fresh cadavers were injected with ultrasound contrast agent. High‐resolution ultrasound of the cubital tunnel was performed during five different arm postures that gradually increased tension on the ulnar nerve and caused cubital tunnel narrowing. Contrast enhancement within the tunnel was measured to quantify perfusion. Cubital tunnel cross‐sectional area was measured to detect compression.

Results

Increasing tension significantly reduced perfusion. When isolated, neither shoulder elevation, elbow flexion, pronation, nor extension of wrist and fingers impaired perfusion. However, combining two or more of these postures led to significant decreases. Significant narrowing of the cubital tunnel was seen in full elbow flexion and shoulder elevation.

Discussion

Combinations of some upper extremity joint positions reduce nerve perfusion, but isolated elbow flexion does not have a significant impact. We hypothesize that elbow splints alone may not influence cubital tunnel perfusion but may only prevent direct compression of the ulnar nerve. Advising patients about upper extremity postures that should be avoided may be more effective.

In Situ Neurolysis of Ulnar Nerve for Patients With Failed Anterior Subcutaneous Transposition - A Case Series

BACKGROUND

Various surgical techniques have been attempted to treat patients with failed anterior subcutaneous transposition performed for cubital tunnel syndrome.

OBJECTIVE

To analyze intraoperative findings of failed anterior subcutaneous transposition and to report the outcome of in Situ neurolysis of ulnar nerve.

METHODS

Patients who, under diagnosis of failed anterior subcutaneous transposition of ulnar nerve, underwent in Situ neurolysis between 2001 and 2018 were included in this study. We excluded patients with follow-up of less than one year, records of traumatic ulnar nerve injury, and concomitant double crush syndrome such as cervical spondylosis causing radicular pain, ulnar tunnel syndrome, or thoracic outlet syndrome. Surgical outcomes were evaluated using visual analog scale (VAS) pain score and Disabilities of the Arm, Shoulder, and Hand (DASH) score, which were assessed before and after surgery. A total of 28 elbows in 27 patients whose average age was 58.5 (range, 31-76) yr were enrolled, and the duration of follow-up was 5.8 (range, 1.0-14.9) yr.

RESULTS

The most common pathologic finding identified during operation was severe adhesion of the transposed nerve in all elbows, followed by incomplete decompression of deep flexor-pronator aponeurosis in 26 elbows (93%). The average VAS pain score improved from 4.9 (range, 2-7) to 1.3 (range, 0-5), and the average DASH score from 31.7 (range, 18.1-66.7) to 14.1 (range, 5.0-46.6). Of the 28 elbows, 27 (96.4%) showed improvement of preoperative symptoms.

CONCLUSION

In Situ neurolysis of ulnar nerve for patients with failed anterior subcutaneous transposition resulted in satisfactory outcome.

Ultrasound-Assisted Precise In Situ Decompression for Cubital Tunnel Syndrome

Objective

To explore the effect of locating the ulnar nerve compression sites and guiding the small incision so as to decompress the ulnar nerve in situ on the elbow by high‐frequency ultrasound before operation.

Methods

A retrospective analysis was conducted on 56 patients who underwent ultrasound‐assisted in situ decompression for cubital tunnel syndrome from May 2018 to August 2019. The patients' average age was 51.13 ± 7.35 years, mean duration of symptoms was 6.51 ± 1.96 months, and mean postoperative follow‐up was 6.07 ± 0.82 months. Nine patients had Dellon's stage mild, 39 had stage moderate, and eight had stage severe. Ultrasound and electromyography were completed in all patients before operation. The presence of ulnar nerve compressive lesion, the specific location, and the reason and extent of compression were determined by ultrasound. A small incision in situ surgery was given to decompress the ulnar nerve according to the pre‐defined compressive sites.

Results

All patients underwent in situ decompression. The compression sites around the elbow were as follows: two in the arcade of Struthers, one in the medial intermuscular septum, four in the anconeus epitrochlearis muscle, five beside the cyst of the proximal flexor carpi ulnaris (FCU), and the remaining 44 cases were all from the compression between Osborne's ligament to the two heads of the FCU. The compression localizations diagnosed by ultrasound were confirmed by operations. Preoperative ultrasound confirmed no ulnar nerve subluxation in all cases. The postoperative outcomes were satisfactory. There was no recurrence or aggravation of symptoms in this group of patients according to the modified Bishop scoring system; results showed that 43 cases were excellent, 10 were good, and three were fair.

Conclusions

High‐frequency ultrasound can accurately and comprehensively evaluate the ulnar nerve compression and the surrounding tissues, thus providing significant guidance for the precise minimally invasive treatment of ulnar nerve compression.

Nerve Conduction Studies in Surgical Cubital Tunnel Syndrome Patients

Background: Electrodiagnostic studies (EDX) serve a prominent role in the diagnostic workup of cubital tunnel syndrome (CBTS), but their reported sensitivity varies widely. The goals of our study were to determine the sensitivity of EDX in a cohort of patients who responded well to surgical cubital tunnel release (CBTR), and whether the implementation of the Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) criteria improves the sensitivity. Methods: We identified 118 elbows with clinical CBTS who had preoperative EDX and underwent CBTR. The EDX diagnoses were CBTS, ulnar neuropathy (UN), and normal ulnar nerves. We divided the 118 elbows into those that received above-elbow stimulation (XE group) and those that did not (non-XE group). We calculated the sensitivities for all groups and reinterpreted the results according to the AANEM guidelines. Results: Cubital tunnel release provided significant relief in 93.6% of the elbows. Based on the EDX reports, 11% patients had clear CBTS, 23% had UN, and 66% showed no UN. The sensitivities were 11.7% for CBTS and 34.2% for any UN. In the XE group, the sensitivity of the EDX reports for CBTS and UN climbed to 33.3% and 58.3%, respectively. When we calculated the across-elbow motor nerve conduction velocity, the sensitivity for CBTS and UN was 87.5% and 100%, respectively. The XE and non-XE groups showed no difference except for sex, bilaterality, concomitant carpal tunnel release, and obesity (P < .05). Conclusion: Implementing AANEM guidelines results in significant improvement in correlation of clinical and electrodiagnostic findings of CBTS.

Reporting Outcomes and Outcome Measures in Cubital Tunnel Syndrome: A Systematic Review

PURPOSE

Comparison between studies assessing outcomes after surgical treatment of cubital tunnel syndrome (CuTS) has proven to be difficult owing to variations in outcome reporting. This study aimed to identify outcomes and outcome measures used to evaluate postoperative results for CuTS.

METHODS

We performed computerized database searches of MEDLINE and EMBASE. Studies with 20 or more patients aged 18 and older who were undergoing medial epicondylectomy, endoscopic decompression, open simple decompression, or decompression with subcutaneous, submuscular, or intramuscular transposition for ulnar neuropathy at the elbow were included. Outcomes and outcome measures were extracted and tabulated.

RESULTS

Of the 101 studies included, 45 unique outcomes and 31 postoperative outcome measures were identified. These included 7 condition-specific, clinician-reported instruments; 4 condition-specific, clinician-reported instruments; 8 patient-reported, generic instruments; 11 clinician-generated instruments; and one utility measure. Outcome measures were divided into 6 unique domains. Overall, 60% of studies used condition-specific outcome measures. The frequency of any condition-specific outcome measure ranged from 1% to 37% of included studies.

CONCLUSIONS

There is marked heterogeneity in outcomes and outcome measures used to assess CuTS. A standardized core outcome set is needed to compare results of various techniques of cubital tunnel decompression.

CLINICAL RELEVANCE

This study builds on the existing literature to support the notion that there is marked heterogeneity in outcomes and outcome measures used to assess CuTS. The authors believe that a future standardized set of core outcomes is needed to limit heterogeneity among studies assessing postoperative outcomes in CuTS to compare these interventions more easily and pool results in the form of systematic reviews and meta-analyses.

Cross-Palm Nerve Grafts to Enhance Sensory Recovery in Severe Ulnar Neuropathy

Background: Intrinsic atrophy and debilitating sensory loss are prominent features of severe ulnar neuropathy with limited surgical options to reliably improve recovery. Restoration of sensation is important to provide protection for the vulnerable ulnar border of the hand. Here, we report our experience with side-to-side sensory nerve grafting from the median to ulnar nerve in the palm to enhance ulnar sensory recovery. Methods: A retrospective chart review identified patients with severe ulnar neuropathy who underwent cross-palm nerve grafting. Included patients had objective loss of protective sensation in the ulnar distribution with 2-point discrimination >8 mm, Semmes-Weinstein monofilament testing (SWMT) >4.56, or no sensory response on nerve conduction testing. Cross-palm side-to-side tension-free grafting from median to ulnar sensory components was performed using short-segment allograft or autografts. Analysis included patient etiology, procedures, nerve conduction studies, objective sensory testing, and Disabilities of the Arm, Shoulder, and Hand Disability score. Results: Forty-eight patients with severe ulnar neuropathy underwent cross-palm nerve grafting between 2014 and 2017. Twenty-four patients had adequate follow-up for inclusion. Of the 24 patients, 21 (87%) had return of protective sensation, 16 (66.7%) had return of diminished light touch sensation, and 6 (25%) had return to normal range sensation within 1 year as assessed by SWMT and/or 2-point discrimination. Patients treated with autograft demonstrated referred sensation to the median nerve distribution. Conclusions: Cross-palm nerve grafting may be a useful adjunct to enhance sensory recovery in severe ulnar neuropathy. Further study to quantify differences in sensory recovery between traditional operative techniques and cross-palm nerve grafting is required.

Classification and Treatment of Ulnar Nerve Subluxation Following Endoscopic Cubital Tunnel Release

Purpose

Endoscopic cubital tunnel release (ECuTR) is an effective procedure to alleviate cubital tunnel syndrome. To improve patient outcomes and lessen concerns regarding ulnar nerve subluxation (UNS) after ECuTR, the current study proposes an intraoperative UNS classification system and subsequent treatment protocol. We present a preliminary report of patients treated under these guidelines.

Methods

We retrospectively reviewed 87 patients (100 ECuTRs). Nerve mobility was classified during surgery, in which grade 1 = no movement or partial subluxation; deep retrocondylar groove and/or no generalized hypermobility (no further intervention); grade 2 = partial subluxation; shallow retrocondylar groove and/or inherent generalized hypermobility (required medial epicondylectomy); and grade 3 = complete anterior dislocation (required medial epicondylectomy or anterior transposition). Clinical outcomes at final follow-up (mean ± SD, 34 ± 20.3 weeks; range, 5–89 weeks) were collected and included Disabilities of the Arm, Shoulder, and Hand questionnaires, visual analog scale pain score, grip and pinch strength, 2-point discrimination, and range of motion.

Results

We report 37 patients (42 cases), grade 1 (n = 30), grade 2 (n = 1), and grade 3 (n = 11). Gross grip strength, lateral, 3-jaw chuck, and precision pinch strength recovered 87%, 90%, 105%, and 87%, respectively. Wrist and elbow range of motion returned to normal limits, 2-point discrimination improved to normal scores at final follow-up, Disabilities of the Arm, Shoulder, and Hand scores were reduced from 59.8 before to 29.9 after surgery, and visual analog scale pain score improved from 7.2 before to 2.5 after surgery (P < .001).

Conclusions

To our knowledge, this is the first study to classify UNS after ECuTR and describe a guideline for ensuing treatment. Our preliminary report of patients shows satisfactory outcomes, which suggests that our intraoperative UNS classification system has promise in preventing adverse complications of ulnar nerve hypermobility after ECuTR.

Type of study/level of evidence

Therapeutic IV.

Perineural Dextrose and Corticosteroid Injections for Ulnar Neuropathy at the Elbow: A Randomized Double-blind Trial

OBJECTIVE

To assess the effects of perineural corticosteroid and 5% dextrose water (D5W) injections in patients with mild to moderate ulnar neuropathy at the elbow (UNE).

DESIGN

Prospective, randomized, double-blind, controlled trial (6-month follow-up).

SETTING

Outpatients of local medical center settings.

PARTICIPANTS

Patients (N=36) with mild to moderate UNE were randomized, and 33 participants were included in the final data analysis.

INTERVENTIONS

Patients were administered a single perineural injection with 5 mL D5W and 3 mL corticosteroid (triamcinolone acetonide, 10mg/mL) mixed with 2 mL normal saline under ultrasound guidance in the dextrose and steroid groups, respectively.

MAIN OUTCOME MEASURES

The visual analog scale digital pain or paresthesia/dysesthesia score was the primary outcome. The secondary outcomes were the Disabilities of the Arm, Shoulder, and Hand questionnaire, motor nerve conduction velocity, and cross-sectional area (CSA) of the ulnar nerve. The measurement assessment was conducted before and 1, 3, 4, and 6 months after injection.

RESULTS

Thirty-three patients completed the study. Both injections were found to be equally effective at most measurement points, although the dextrose group experienced larger reductions in symptom severity and CSA of the ulnar nerve from the third month onward.

CONCLUSIONS

We suggest D5W as a more suitable injectate for perineural injection in patients with UNE.

Cubital tunnel syndrome: a surgical modification to in situ decompression to improve results

BACKGROUND

The gold standard for surgical treatment of cubital tunnel syndrome is in situ decompression. However, this procedure does not come without complications. Subluxation of the ulnar nerve and ulnar nerve neuritis from adhesion formation remain 2 potential complications after this procedure. It has been shown in the literature that young, active, male patients are most likely to have these complications postoperatively. We have developed a modification to in situ decompression by developing a fascial turnover flap and using a porcine submucosa extracellular matrix (Axogen) to help reduce both ulnar nerve subluxation and adhesion formation postoperatively.

METHODS

Thirteen patients underwent cubital tunnel surgery by the highlighted technique to prevent postoperative ulnar nerve subluxation and adhesion formation. Patient outcomes including elbow range of motion, functional status, paresthesia, and grip strength were recorded.

RESULTS

Of the 13 patients, 10 had excellent results, 1 had a good result, and 2 required revision with anterior transposition of the nerve. The mean Mayo Elbow Performance Score of the 11 patients not needing revision was 92.7.

CONCLUSION

The described surgical technique provides surgeons with the ability to directly decompress the ulnar nerve while decreasing postoperative complications such as instability and adhesion formation.

In idiopathic cubital tunnel syndrome, ulnar nerve excursion and instability can be reduced by repairing Osborne's ligament after simple decompression

Osborne's modified decompression involves repairing Osborne's ligament beneath the ulnar nerve after simple decompression for idiopathic cubital tunnel syndrome. In this retrospective interrupted time series, 31 patients underwent modified simple decompression and 20 patients underwent conventional simple decompression. In the modified simple decompression group, the ulnar nerve length was measured at operation in full elbow flexion and extension before and after repair of Osborne's ligament. Ulnar nerve instability during elbow motion was measured using ultrasonography before operation and at 12 months after operation. In patients treated by modified simple decompression, the ulnar nerve length in full elbow flexion reduced significantly after repair of Osborne's ligament. At 12 months after surgery, the grade of ulnar nerve instability was lower in the modified simple decompression group than in the conventional simple decompression group. The clinical outcomes did not differ significantly between the groups at 24 months after operation. Level of evidence: III.

Intraoperative Subluxation of the Ulnar Nerve: Use of a Triceps Sling Reconstruction Technique

PURPOSE

To determine whether the triceps sling reconstruction technique is a safe and effective treatment of intraoperative ulnar nerve subluxation after in situ decompression.

METHODS

Twelve patients who underwent a triceps sling reconstruction for intraoperative ulnar nerve subluxation after in situ release were retrospectively reviewed. The triceps sling technique consists of harvesting a small, distally based strip of triceps tendon and suturing the proximal end of the strip to the posterior aspect of the released Osborne ligament. Thus, a sling is created between the medial epicondyle and the olecranon, preventing the nerve from subluxating. Patients were clinically evaluated before and after surgery. Visual analog scale pain scores, static 2-point discrimination, strength, and Disabilities of the Arm, Shoulder, and Hand score were assessed.

RESULTS

At a mean follow-up of 31 months (range, 24-38 months), there was a significant improvement in mean visual analog pain scores from 8.6 to 0.2. Static 2-point discrimination was improved from a mean of 9.1 mm before surgery to 5.7 mm afterward. Strength improved by a mean of 33% and 30% with grip and pinch, respectively. Mean Disabilities of the Arm, Shoulder, and Hand score improved from 45.9 to 3.7. No subluxation of the ulnar nerve was noted after surgery. No other complications were noted. No reoperations were required during the follow-up period.

CONCLUSIONS

Triceps sling reconstruction is a safe treatment in patients with intraoperative ulnar nerve subluxation after in situ decompression.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

A systematic review and meta-analysis comparing open versus endoscopic in situ decompression for the treatment of cubital tunnel syndrome

To examine whether endoscopic in situ decompression (EISD) or open in situ decompression (OISD) would have superior outcomes with lower morbidity in patients with idiopathic cubital tunnel syndrome, we reviewed all studies compared both surgical techniques with regard to postoperative outcomes and complication profile in a systematic review design with meta-analysis. Two independent reviewers conducted a PRISMA-compliant search of PubMed, EMBASE, and the Cochrane Library databases for relevant studies about clinical comparisons of OISD and EISD in cubital tunnel syndrome. We performed all meta-analyses with the Review Manager 5.3 software. For dichotomous variables, the risk ratio (RR) and 95% confidence intervals (CIs) were calculated. For continuous variables, the mean difference (MD) and 95% CIs were calculated. The level of significance was set as p < 0.05. Finally, 8 articles with 582 patients finally were included in this meta-analysis. Pooled analysis showed that the difference in Bishop score, visual analogue scale score reduction, postoperative satisfaction, postoperative hematoma rate and secondary surgical procedures were not statistically significant between the EISD group and the OISD group (p > 0.05). However, pooled results showed that patients who underwent EISD had a greater improvement in the scar tenderness/elbow pain than did those who underwent OISD with statistical significance (p < 0.0001). This meta-analysis demonstrated that EISD and OISD for surgical treating cubital tunnel syndrome had equivalent efficacy regarding postoperative clinical recovery, whereas the incidences of adverse events of EISD were also same as those with the OISD technique.

Associations Between Insurance Type and the Presentation of Cubital Tunnel Syndrome

PURPOSE

In the setting of cubital tunnel syndrome (CuTS), delays in diagnosis can have permanent effects including sensory loss, muscle weakness, and atrophy of intrinsic hand muscles. This study sought to evaluate the association of insurance type on the severity of CuTS. We hypothesized that publicly insured patients will have delayed presentation to the orthopedics office and more significant condition severity.

METHODS

A retrospective chart review was conducted for all patients evaluated for CuTS between December 2013 and January 2018 by a fellowship-trained orthopedic hand and upper extremity surgeon at our tertiary referral center. Insurance type, demographics, and measures of CuTS severity were compared.

RESULTS

Patients presenting with CuTS of severity greater than or equal to McGowan stage 2A had 4.4-fold greater odds of being publicly insured than privately. Motor and sensory velocities across the elbow were diminished at 42.2 ± 13.9m/s and 33.0 ± 20.8m/s in publicly insured patients compared with 47.5 ± 11.3 m/s and 47.0 ± 16.4m/s for privately insured patients. The same trend was present for motor and sensory amplitudes at 6.6 ± 3.8 μV and 16.9 ± 17.8 μV in publicly insured patients compared with 8.5 ± 3.2 μV and 26.0 ± 18.9 μV in privately insured patients. Patients with public insurance were symptomatic for longer prior to their initial visit, on average 82.8 ± 86.5 weeks, compared with 42.4 ± 58.9 weeks for patients with private insurance.

CONCLUSIONS

Publicly insured patients were significantly delayed in seeing an orthopedic surgeon for evaluation and treatment of CuTS and presented with more severe clinical and electrodiagnostic findings compared with privately insured patients. These findings suggest that insurance type, among other socioeconomic factors, may be a barrier to CuTS care.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prevalence IV.

Ultrasound Measurements and Assessments of the Ulnar Nerve at the Elbow and Cubital Tunnel: A Scoping Review

Ulnar neuropathy at the elbow (UNE) is the second most frequent peripheral nerve entrapment neuropathy in the upper extremity. The diagnosis is determined through a combination of history, physical examination, and electrodiagnostic testing. However, the use of high-resolution sonography is increasing, with sonographic measurements of ulnar nerve dimension established as a reliable diagnostic criterion for UNE. Sonographic imaging can describe anatomical features beyond ulnar nerve size, and therefore additional observations could potentially be used in UNE diagnosis and treatment follow-up. This review was a scoping of the literature on different sonographic measurements and assessments that have been reported to evaluate the ulnar nerve and cubital tunnel. This should provide a guide to scanning protocols for sonographers.

Outcomes of ulnar nerve anterior transmuscular transposition and significance of ulnar nerve instability in cubital tunnel syndrome

BACKGROUND

We investigated the experience of a single surgeon with ulnar nerve anterior transmuscular transposition with the patient in the lateral decubitus position for cubital tunnel syndrome.

METHODS

The medical records of all patients who underwent primary or revision ulnar nerve anterior transmuscular transposition were screened to define a cohort of 156 patients (162 limbs) for further study of demographic and disease-specific data and retrospective assessment of short-term outcomes. Ulnar neuropathy severity was stratified by McGowan grade. A prospective cohort composed of 49 patients (51 limbs) with a minimum 2-year follow-up volunteered to complete patient outcome surveys, and some presented for an ulnar nerve-focused examination to assess long-term outcomes.

RESULTS

The overall patient satisfaction rate was 92%, with statistically significant improvements in ulnar sensation and intrinsic strength at short- and long-term follow-up. Outcomes were better for lower McGowan grades than for higher grades and better in primary cases than in revision cases. Ulnar nerve instability was observed in 69 of 162 cases (43%) in this series. A major complication occurred in 7 cases (4.3%), but all were mitigated by contributory patient-related factors. Reoperation for recurrent ulnar paresthesia was required in 4 cases (2.5%). No operations or outcomes were compromised by the lateral decubitus position.

DISCUSSION AND CONCLUSION

Ulnar nerve anterior transmuscular transposition in the lateral decubitus position is a good surgical option for primary or recurrent cubital tunnel syndrome and remains our preferred procedure. The high prevalence of ulnar nerve instability observed in this study is a factor worthy of consideration by surgeons and patients weighing the surgical options for ulnar neuropathy at the elbow.

Retrospective, nonrandomized analysis of subcutaneous anterior transposition versus in situ decompression of the ulnar nerve of military service members

HYPOTHESIS

The objective of this study was to compare the subjective and objective midterm functional clinical outcomes of subcutaneous anterior transposition (SAT) vs. in situ decompression (SD) of the ulnar nerve for the treatment of cubital tunnel syndrome.

METHODS

The US Military Health System was queried to identify all cases of ulnar neuroplasty (Current Procedural Terminology code 64718) between 2006 and 2010. Patient charts were reviewed to identify cases of isolated SAT and SD, and demographic and surgical variables were collected. The primary outcome variable was the Disabilities of the Arm, Shoulder and Hand score. The inclusion criteria were isolated primary SAT or SD and adult active-duty service members with a minimum 6-year telephone follow-up. Terminal follow-up was determined by a telephone interview. The exclusion criteria were revision procedures, trauma, cases that included other procedures (eg, medial epicondylectomy, submuscular transposition, arthroscopy, or fracture fixation), non-active-duty service members, patients without a minimum 6-year telephone follow-up, and patients who had incomplete medical records or could not be reached to complete the survey.

RESULTS

A total of 65 SD and 67 SAT patients met the inclusion and exclusion criteria, with a 72% telephone interview response rate. The average age was 32.3 years for all patients, with an average follow-up period of 6.5 years for SD patients and 6.3 years for SAT patients. SD patients had a lower mean Disabilities of the Arm, Shoulder and Hand score than SAT patients. No difference in reoperation rate was found.

CONCLUSION

The active-duty cohort reported positive outcomes and a low reoperation rate at 6-year follow-up both after SAT and after SD. SD patients had mildly superior clinical outcomes compared with SAT patients.

The Blocking Flap for Ulnar Nerve Instability After In Situ Release: Technique and a Grading System of Ulnar Nerve Instability to Guide Treatment

In situ ulnar nerve release has been gaining popularity as a simple, effective, and low-morbidity procedure for the treatment of cubital tunnel syndrome. One concern with the technique is how to manage the unstable ulnar nerve after release. It is unclear how much nerve subluxation will lead to problems and surprisingly there is no grading system to assess ulnar nerve instability. I propose such a grading system, as well as a new technique to stabilize the unstable ulnar nerve. The blocking flap technique consists of raising a rectangular flap off the flexor/pronator fascia and attaching it to the posterior subcutaneous flap so that it blocks the nerve from subluxation/dislocation.

Prevalence of cubital tunnel syndrome among dock workers, Saint Sebastian, São Paulo, Brazil

Background

Ports play a substantial role in the Brazilian economy.Despite the large number of port workers, few studies report that the most common musculoskeletal disorders among them involve the upper limbs, including carpal tunnel syndrome, rotator cuff syndrome, cervicalgia and cubital tunnel syndrome.The latter is a neuritis caused by compression of the ulnar nerve at the cubital tunnel (CuTS) on the elbow.

Objective

To estimate the prevalence of a suggestive diagnosis of CuTS among port workers.

Method

Seventy-two independent port workers registered with the Labor Management Organ (Órgão Gestor de Mão de Obra - OGMO), Port of Saint Sebastian, were evaluated based on a semi-structured questionnaire and clinical examination, including investigation of pain on palpation of the middle area of the elbow and two maneuvers specific for CuTS, namely, the pressure provocation and maximal flexion tests.

Results

The average age of the participants was 48.49 years old, and their average length in the job 23.13 years.Suggestive diagnosis of CuTS was established for five participants.In only two cases elbow pain had begun before, and in three after starting work at the port.

Conclusion

The prevalence of a suggestive diagnosis of CuTS was 6.9%, and was higher among the participants with longer length in the job (over one year).

Cubital tunnel syndrome: Anatomy, clinical presentation, and management

Cubital tunnel syndrome is the second most common peripheral nerve compression seen by hand surgeons. A thorough understanding of the ulnar nerve anatomy and common sites of compression are required to determine the cause of the neuropathy and proper treatment. Recognizing the various clinical presentations of ulnar nerve compression can guide the surgeon to choose examination tests that aid in localizing the site of compression. Diagnostic studies such as radiographs and electromyography can aid in diagnosis. Conservative management with bracing is typically trialed first. Surgical decompression with or without ulnar nerve transposition is the mainstay of surgical treatment. This article provides a review of the ulnar nerve anatomy, clinical presentation, diagnostic studies, and treatment options for management of cubital tunnel syndrome.

Endoscopic versus Open In Situ Cubital Tunnel Release: A Systematic Review of the Literature and Meta-Analysis of 655 Patients

BACKGROUND

Cubital tunnel syndrome is the second most common peripheral entrapment syndrome. To date, there is no true consensus on the ideal surgical management. A minimally invasive, endoscopic approach has gained popularity but has not been adequately compared to the more traditional, open approach.

METHODS

With compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic review was performed to identify studies published between 1990 and 2016 that compared the efficacy of endoscopic cubital tunnel release to open cubital tunnel release. A meta-analysis was then performed through a random-effects model with inverse variance weighting to calculate I values for heterogeneity analysis. Forest plots were constructed for each analysis group.

RESULTS

Five studies involving 655 patients (endoscopic cubital tunnel release, n = 226; open cubital tunnel release, n = 429) were included. Meta-analysis revealed no significant superiority of open release in achieving an "excellent" or "good" Bishop score (OR, 1.27; 95 percent CI, 0.59 to 2.75; p = 0.54) and reduction in visual analogue scale score (mean difference, -0.41; 95 percent CI, -1.49 to 0.67; p = 0.46). However, in the endoscopic release cohort, lower rates of new-onset scar tenderness/elbow pain were found (OR, 0.19; 95 percent CI, 0.07 to 0.53; p = 0.002), but there was a higher incidence of postoperative hematomas (OR, 5.70; 95 percent CI, 1.20 to 27.03; p = 0.03). The reoperation rate in the endoscopic and open release groups was 4.9 and 4.1 percent, respectively (p = 0.90).

CONCLUSIONS

The authors demonstrated equivalent overall clinical improvement between endoscopic and open cubital tunnel release in terms of Bishop score and visual analogue scale score reduction. Because of the low power of most studies, further investigations with a larger patient population and longer follow-up are needed to better characterize the role of endoscopic cubital tunnel release.

Case-Cohort Studies: Design and Applicability to Hand Surgery

Observational studies are common research strategies in hand surgery. The case-cohort design offers an efficient and resource-friendly method for risk assessment and outcomes analysis. Case-cohorts remain underrepresented in upper extremity research despite several practical and economic advantages over case-control studies. This report outlines the purpose, utility, and structure of the case-cohort design and offers a sample research question to demonstrate its value to risk estimation for adverse surgical outcomes. The application of well-designed case-cohort studies is advocated in an effort to improve the quality and quantity of observational research evidence in hand and upper extremity surgery.

Shear-wave elastography: a new potential method to diagnose ulnar neuropathy at the elbow

Objectives

The primary aim of this study was to verify if shear-wave elastography (SWE) can be used to diagnose ulnar neuropathy at the elbow (UNE). The secondary objective was to compare the cross-sectional areas (CSA) of the ulnar nerve in the cubital tunnel and to determine a cut-off value for this parameter accurately identifying persons with UNE.

Methods

The study included 34 patients with UNE (mean age, 59.35 years) and 38 healthy controls (mean age, 57.42 years). Each participant was subjected to SWE of the ulnar nerve at three levels: in the cubital tunnel (CT) and at the distal arm (DA) and mid-arm (MA). The CSA of the ulnar nerve in the cubital tunnel was estimated by means of ultrasonographic imaging.

Results

Patients with UNE presented with significantly greater ulnar nerve stiffness in the cubital tunnel than the controls (mean, 96.38 kPa vs. 33.08 kPa, p < 0.001). Ulnar nerve stiffness of 61 kPa, CT to DA stiffness ratio equal 1.68, and CT to MA stiffness ratio of 1.75 provided 100% specificity, sensitivity, positive and negative predictive value in the detection of UNE. Mean CSA of the ulnar nerve in the cubital tunnel turned out to be significantly larger in patients with UNE than in healthy controls (p < 0.001). A weak positive correlation was found in the UNE group between the ulnar nerve CSA and stiffness (R = 0.31, p = 0.008).

Conclusions

SWE seems to be a promising, reliable and simple quantitative adjunct test to support the diagnosis of UNE.

Key Points

• SWE enables reliable detection of cubital tunnel syndrome

• Significant increase of entrapped ulnar nerve stiffness is observed in UNE

• SWE is a perspective screening tool for early detection of compressive neuropathies

Effect of dry needling on cubital tunnel syndrome: Three case reports

This case series describes three patients who presented with right medial elbow pain managed unsuccessfully with conservative treatment that included medication, massage, exercise therapy, ultrasound therapy, neurodynamic mobilization, and taping. Diagnosis of cubital tunnel syndrome was based on palpatory findings, a positive elbow flexion test, and a positive Tinel's sign. Conventionally, the intervention for this entrapment has been surgical decompression, with successful outcomes. This is potentially a first-time description of the successful management of cubital tunnel syndrome with dry needling (DN) using a recently published DN grading system. The patients were seen twice a week for 2 weeks with immediate improvements noted in all the outcome measures after the first treatment session. At discharge, they were pain-free and fully functional, which was maintained up to a 6-month follow-up.

Predictors of surgical outcomes after in situ ulnar nerve decompression for cubital tunnel syndrome

Background

In the treatment of cubital tunnel syndrome (CuTS), in situ ulnar nerve decompression is commonly used. This study aims to investigate predictive factors for poor recovery and ulnar nerve instability following this procedure.

Methods

We enrolled 235 patients who underwent in situ ulnar nerve decompression for the treatment of CuTS from January 2010 to December 2014. All patients underwent >2 years' follow-up. The primary outcome was postoperative recovery, which was assessed by Messina's criteria, and the secondary outcome was postoperative ulnar nerve instability. Potential risk factors were collected from demographic data and electrodiagnostic test, which included age, gender, body mass index, history of tobacco or alcohol use, history of major medical comorbidities, disease duration, preoperative severity, motor conduction velocity, and sensory conduction velocity.

Results

A total of 208 patients (88.5%) had satisfactory outcomes, while the other 27 patients (11.5%) had not. There were 25 patients (10.6%) showing postoperative ulnar nerve instability during follow-up. The multivariate analysis showed that only severe preoperative symptom (odds ratio [OR], 3.06; 95% confidence interval [CI], 2.16-4.32) was associated with unsatisfactory postoperative outcomes in patients with CuTS (P<0.001). In the model investigating independent factors associated with postoperative ulnar nerve instability, we found that young age (OR, 2.41; 95% CI, 1.63-3.58) was associated with the incidence of postoperative ulnar nerve instability (P<0.001).

Conclusion

We found that severe preoperative symptom was associated with unsatisfactory postoperative outcomes, and young age was a risk factor for the incidence of postoperative ulnar nerve instability. Patients with these risk factors should be informed of the possibility of worse surgical outcomes.

Diffusion tensor imaging in the musculoskeletal and peripheral nerve systems: from experimental to clinical applications

Magnetic resonance imaging (MRI) is a well-established imaging modality which is used in all districts of the musculoskeletal and peripheral nerve systems. More recently, initial studies have applied multiparametric MRI to evaluate quantitatively different aspects of musculoskeletal and peripheral nerve diseases, thus providing not only images but also numbers and clinical data. Besides ¹H and ³¹P magnetic resonance spectroscopy, diffusion-weighted imaging (DWI) and blood oxygenation level-dependent imaging, diffusion tensor imaging (DTI) is a relatively new MRI-based technique relying on principles of DWI, which has traditionally been used mainly for evaluating the central nervous system to track fibre course. In the musculoskeletal and peripheral nerve systems, DTI has been mostly used in experimental settings, with still few indications in clinical practice. In this review, we describe the potential use of DTI to evaluate different musculoskeletal and peripheral nerve conditions, emphasising the translational aspects of this technique from the experimental to the clinical setting.

[Cubital tunnel syndrome : Diagnostics and therapy]

Cubital tunnel syndrome is the second most common nerve compression syndrome observed in the upper extremity. Mechanical irritation of the ulnar nerve is also found in the upper and the lower arm even though cubital tunnel syndrome is documented most of the time. Apart from clinical examination electrophysiological testing is the most important contributor to the therapy decision. Depending on the clinical manifestation conservative treatment with elbow splinting may be appropriate. In the event of persistent or advanced nerve irritation surgical decompression may be the sensible intervention. Open or endoscopically assisted in situ decompression is currently recommended as the primary intervention while anterior transposition of the ulnar nerve is recommended for revision surgery.

Trends in Open and Endoscopic Cubital Tunnel Release in the Medicare Patient Population

BACKGROUND

Cubital tunnel syndrome (CUT) is the second most common peripheral neuropathy with an annual incidence of 24.7 per 100 000, affecting nearly twice as many men as women. With increasing focus on cost-effectiveness and cost-containment in medicine, a critical understanding of utilization of health care resources for open and endoscopic approaches for cubital tunnel release is of value. The purpose of this study was to evaluate the costs and utilization trends of open and endoscopic cubital tunnel release.

METHODS

We performed a retrospective review of a Medicare database within the PearlDiver Supercomputer (Warsaw, Indiana) for procedures performed from 2005 to 2012. Annual utilization, charges, reimbursement, demographic data, and compound annual growth rate were evaluated.

RESULTS

Our query returned 262 104 patients with CUT, of which 69 378 (26.5%) and 4636 (1.8%) were surgically managed with open and endoscopic release respectively. Average charges were higher in endoscopic release ($3798) than open release ($3197) while reimbursements were higher in open releases ($1041) than endoscopic release, ($866). Both were performed most commonly in the <65 years age range.

CONCLUSIONS

Despite the unexpectedly lower reimbursement rate with endoscopic release, endoscopy utilization is growing faster than open releases in the Medicare population. Lower reimbursement is likely related to lack of a dedicated current procedural terminology code for endoscopic cubital tunnel release.

Muscular atrophy in severe cases of cubital tunnel syndrome: prognostic factors and outcome after surgical treatment

BACKGROUND

Cubital tunnel syndrome (CuTS) is a frequent neuropathy, leading to sensor-motoric dysfunction. Many patients even present with muscular atrophy as a sign for severe and long-lasting nerve impairment, usually suggesting unfavourable outcome. We analysed if those patients benefit from surgical treatment on a long-term basis.

METHODS

Between January 2010 and March 2015, 42 consecutive cases of CuTS with atrophy of the intrinsic hand muscles were surgically treated in our department. Clinical data of the treatment course and postoperative results were collected. Follow-up was prospectively assessed according to McGowen grading and Bishop outcome score. Mean follow-up time was 39.8 (±17.0) months.

RESULTS

All patients were treated with in situ decompression; in 33%, submuscular transposition was performed. Forty-five percent showed improvement of sensory deficits and 57% showed improvement of motor deficits 6 months after the operation. Atrophy improved in 76%. At the time of follow-up, 79% were satisfied with the postoperative result and 77% of patients reached good or excellent outcome according to modified Bishop rating scale. Patients with improvement of atrophy had significantly shorter symptom duration period (7 ± 10 months vs 26 ± 33 months; p < 0.05). In the case of intraoperative pseudoneuroma observation, atrophy improvement was less likely (p < 0.05).

CONCLUSIONS

In severe cases of CuTS with atrophy of the intrinsic hand muscles, surgical treatment enables improvement of sensory function, motor function and atrophy even in cases with muscular atrophy. Atrophy improvement was more likely in cases of short symptom duration and less likely in cases with pseudoneuroma.

Recurrent cubital tunnel syndrome treated with revision neurolysis and amniotic membrane nerve wrapping

BACKGROUND

Perineural scarring of the ulnar nerve is a predominant cause of symptom recurrence after surgical treatment for primary cubital tunnel syndrome (CuTS). We report our preliminary experience in revision ulnar nerve decompression and nerve wrapping with an amniotic membrane allograft adhesion barrier for treatment of recurrent CuTS.

METHODS

We performed a retrospective review with prospective follow-up of patients with recurrent CuTS who were treated with revision neurolysis with amniotic membrane nerve wrapping. Preoperative elbow motion, grip and pinch strengths, pain level on the visual analog scale level, and the 11-item version of the Disabilities of the Arm, Shoulder and Hand functional outcome score were compared with postoperative values using paired t testing. Symptom characteristics, physical examination findings, complications, and level of satisfaction were also obtained.

RESULTS

Eight patients (mean age, 47.5 years) who had undergone at least 2 prior ulnar nerve operations satisfied study inclusion. At mean postoperative follow-up of 30 months, significant improvements were noted across all patients in visual analog scale pain levels (-3.5 vs. preoperatively; P < .0001), 11-item version of the Disabilities of the Arm, Shoulder and Hand scores (-30 vs. preoperatively; P < .0001), and grip strength (+25 pounds vs. preoperatively; P < .0001). Pinch strength and elbow motion were also significantly improved for those patients with comparative preoperative data available. All patients expressed subjective satisfaction with their results. No adverse reactions or complications occurred in any patients.

CONCLUSIONS

Ulnar nerve wrapping with amniotic membrane allograft, when combined with revision neurolysis, was a safe and subjectively effective treatment for patients with debilitating recurrent CuTS.