Subjective outcome, neurophysiological investigations, postoperative complications and recurrence rate of partial medial epicondylectomy in cubital tunnel syndrome

Anconeus epitrochlearis muscle (epitrochlearisanconeus muscle; Musculus epitrochleoanconeus) with cubital tunnel syndrome - a rare but relevant clinical entity

BACKGROUND

Compression of the ulnar nerve at the elbow within the cubital tunnel is related to the anatomical structures and is generally believed to be caused by Osborne's ligament (also known as the cubital retinaculum). However, in rare cases an anatomical variation of the developmental peculiarity of a remaining anconeus epitrochlearis muscle may be responsible for the disease.

METHODS

We present a series of five cases in which an anconeus epitrochlearis muscle was found as the cause of illness.

RESULTS

All patients presented with typical symptoms of numbness and tingling in the hand and ulnar fingers, and recurring pain as well as weakness of the ulnar innervated muscles. With neurophysiologically confirmed diminished nerve conduction velocity and unsuccessful conservative treatment, surgical decompression revealed an anconeus epitrochlearis muscle as the reason of compression. Full symptom relief was achieved immediately after the procedure in all cases.

CONCLUSIONS

This article strives to call attention to this entity when diagnosing ulnar nerve compression. Myectomy and medial epicondylectomy is the preferred treatment option in such cases.

The management of failed cubital tunnel decompression

Cubital tunnel decompression is a commonly performed operation with a much higher failure rate than carpal tunnel release.

Failed cubital tunnel release generally occurs due to an inadequate decompression in the primary procedure, new symptoms due to an iatrogenic cause, or development of new areas of nerve irritation.

Our preferred technique for failed release is revision circumferential neurolysis with medial epicondylectomy, as this eliminates strain, removes the risk of subluxation, and avoids the creation of secondary compression points.

Adjuvant techniques including supercharging end-to-side nerve transfer and nerve wrapping show promise in improving the results of revision surgery.

Limited quality research exists in this subject, compounded by the lack of consensus on diagnostic criteria, classification, and outcome assessment.

Cite this article: EFORT Open Rev 2021;6:735-742. DOI: 10.1302/2058-5241.6.200135

Treatment of Peripheral Nerve Compression Syndromes of the Upper Extremities: a Systematic Review

BACKGROUND

Nerve compression syndromes are referred to as chronic irritation or pressure palsies of peripheral nerves in areas of preformed anatomical constriction. Carpal tunnel syndrome is the most common nerve compression syndrome, followed by cubital tunnel syndrome. In addition, less frequent nerve compression syndromes of the upper extremities that affect the median, ulnar or radial nerves have been described. This review provides an overview of current treatment options for nerve compression syndromes of the upper extremities.

STUDY DESIGN

Systematic overview.

METHODS

Based on established national (AWMF) and international guidelines as well as the Cochrane Library, we performed a systematic literature search on PubMed (NLM), focusing on randomised controlled trials.

RESULTS

Over the research period (2012 - 2020), there were 43 randomised trials that investigated surgical carpal tunnel release methods, 68 that compared different conservative therapies and 12 that compared surgical versus conservative treatments. Furthermore, eight studies analysed surgical techniques and four analysed conservative techniques for cubital tunnel syndrome. No randomised trials were conducted on the less common peripheral nerve compression syndromes, but case reports and observational studies were conducted.

CONCLUSION

For carpal and cubital tunnel syndromes, there are evidence-based diagnostic methods as well as therapeutic recommendations based on randomised and controlled trials. When diagnosis is made after clinical examination and supported by radiological and electrophysiological evaluation, surgical treatment is considered superior to conservative treatment. In particular, excellent long-term results can be achieved by surgery for carpal and cubital tunnel syndromes. More controlled studies are needed to establish evidence-based therapeutic recommendations for the less common nerve compression syndromes, which are somewhat controversially and inconsistently defined.

A novel local adipofascial flap for the management of recalcitrant ulnar tunnel syndrome

Ulnar tunnel syndrome is the second most common upper-limb peripheral nerve compression syndrome. Recurrence or persistence of symptoms after primary surgery is found in 9.9%-21% of cases. The main cause of failure is peri- and endo-neural fibrosis, and management is difficult and controversial. Revision of nerve neurolysis combined with freestyle adipofascial flap provides nerve decompression and coverage with vascularized tissue, which prevents scar tissue formation around the nerve and restores glide. We performed a preliminary vessel-injected cadaver study. The perforating vessels from the posterior recurrent ulnar artery vascularize the medial adipose and fascial tissues of the elbow, allowing elevation of an adipofascial flap which is able to reach the ulnar nerve. Eight patients with neuropathic ulnar nerve pain in recalcitrant ulnar tunnel syndrome due to peri- and/or endo-neural fibrosis were treated by neurolysis, and the nerve was covered with an ulnar adipofascial flap. All patients were evaluated by percussion test, visual analog scale for pain, electromyography, electroneurography and ultrasound, and were classified according to the McGowan classification as modified by Goldberg. The study was approved by the review board. All patients had good 4-year outcome, with complete return to daily activity, work and sports 4 months after surgery. The results of this novel surgical technique were encouraging, without complications or donor site morbidity. Adipofascial flap combined with neurolysis could be a valid solution in the treatment of recalcitrant ulnar tunnel syndrome.

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.

Symptom Recurrence After Endoscopic Cubital Tunnel Release

Purpose

To evaluate the recurrence of symptoms after an endoscopic cubital tunnel release using the technique of Hoffmann and Siemionow.

Methods

We retrospectively reviewed 286 consecutive patients who underwent Hoffmann and Siemionow’s technique of endoscopic cubital release by a single surgeon during an 8-year period. Inclusion criteria were adult patients without previous elbow surgery, pathology, or trauma, and patients with a minimum 3-months’ postoperative follow-up. We evaluated symptom recurrence rate and assessed risk factors that would affect recurrence.

Results

A total of 223 patients met inclusion criteria, 204 of whom (91.5%) had improvement at 3 months after surgery. Eleven patients (4.9%) had persistent symptoms and 8 (3.6%) had recurrent symptoms at a mean of 16 months (range, 3–93 months) after the primary surgery. Intraoperative ulnar nerve subluxation had a statistically significant relationship with symptom recurrence.

Conclusions

Symptoms recurred at a rate of 3.6% after Hoffmann and Siemionow’s endoscopic cubital tunnel release. This is comparable to other endoscopic or open techniques for cubital tunnel release. The procedure has the added advantage of less tissue dissection. Intraoperative ulnar nerve subluxation seems to be associated with symptom recurrence.

Type of study/level of evidence

Therapeutic IV.

Management of cubital tunnel syndrome by anterior trans-muscular transposition of the ulnar nerve

Background

Various surgical options are used for the treatment of ulnar nerve entrapment at the elbow. In this study, anterior trans-muscular transposition of the ulnar nerve was used for the treatment of cubital tunnel syndrome.

Objectives

To evaluate the surgical results of anterior trans-muscular transposition technique for the treatment of cubital tunnel syndrome with particular emphasis on clinical outcome.

Methods

Forty patients with cubital tunnel syndrome were operated using anterior trans-muscular transposition technique. Patients were classified into post-operative clinical outcome grades according to the Wilson & Krout criteria, and they were followed up by visual analog scale (VAS), the Disability of Arm Shoulder and Hand (DASH) questionnaire, electrophysiological study, and post-operative clinical evaluation.

Results

Forty patients with cubital tunnel syndrome who underwent anterior trans-muscular transposition of the ulnar nerve show a significant clinical improvement at 24 months post-surgery regarding visual analog scale (VAS), the Disability of Arm Shoulder and Hand (DASH) questionnaire, electrophysiological study, and the Wilson & Krout grading as 87.5% of the patients recorded excellent and good outcome.

Conclusion

Anterior transmuscular transposition of the ulnar nerve is a safe and effective treatment for ulnar nerve entrapment at the elbow.

A systematic review of medial epicondylectomy as a surgical treatment for cubital tunnel syndrome

The aim of this study was to review the literature of decompression of the cubital tunnel with medial epicondylectomy and to assess outcomes and complications. Twenty-one case series reported on 886 medial epicondylectomies. The mean percentage of patients obtaining improvement of one or more McGowan grade was 79%. The mean percentage obtaining a good/excellent Wilson Krout grade of outcome was 83%. Of six comparative studies, two showed no significant differences in outcomes between medial epicondylectomy and transposition procedures, and three reported better outcomes with medial epicondylectomy. One reported similar outcomes with medial epicondylectomy and simple decompression. The existing literature on medial epicondylectomy is of limited methodological quality and does not allow for firm conclusions to be drawn regarding its efficacy compared with other surgical techniques. Further studies should aim for high methodological quality, randomized comparison with simple decompression or anterior transposition and should utilize standardized outcome measures.

LEVEL OF EVIDENCE

II.

Ulnar nerve entrapment at the elbow. A surgical series and a systematic review of the literature

Chronic compression of the ulnar nerve at the elbow is the second most common entrapment neuropathy. Various surgical options have been described. Timing of surgery is also debated. In this study we report the long-term results of a consecutive surgical series of anterior subcutaneous transpositions and review the pertinent literature. Sixty consecutive patients underwent anterior subcutaneous transposition at our Institution to treat ulnar nerve compression at the elbow. McGowan scale was used in the neurological exam before surgery. Bishop rating system was used to assess outcome. Seventy-eight% of patients scored good-excellent. None of the patients worsened. No complications and no recurrences were reported. Young age and good pre-operative neurological status (McGowan grade 1) were predictive of favorable outcome both at univariate and at multivariate analysis. No differences in outcome were observed between patients with intermediate (McGowan grade 2) and severe (McGowan grade 3) neuropathy. Thirty-four studies assessing outcome of different surgical techniques were reviewed. Anterior subcutaneous transposition had the lowest recurrence rate with an excellent effectiveness and safety profile. The favorable predictive role for outcome of preoperative neurological status was confirmed. The good long-term clinical results of the present series and the results of literature analysis confirm the value of anterior subcutaneous transposition of the ulnar nerve at the elbow. This technique has a particular effectiveness in most severe compressions, where outcomes are comparable with intermediate neuropathy cases. Moreover, our results suggest an aggressive attitude towards ulnar nerve compression at the elbow, particularly in younger patients.

IS RDW A PREDICTIVE PARAMETER FOR CUBITAL TUNNEL SYNDROME PATIENTS REQUIRING SURGERY?

OBJECTIVE

The aim of this study was to investigate whether haemogram parameters are predictive factors for both the severity of the disease and a decision in favor of surgical treatment in patients with an established diagnosis of cubital tunnel syndrome (CuTS) .

METHODS

The medical files of patients with a diagnosis of CuTS who were followed-up conservatively (n=92) or surgically treated (n=92) were retrospectively screened and the haemogram parameters were recorded .

RESULTS

The receiver operating characteristic (ROC) curve analysis revealed an area of 0.665 under the curve, with 76.3% sensitivity and 84.8% specificity at the cut-off of a red cell distribution width (RDW) level grater than 15.45%. RDW levels higher than 15.5%, electromyography (EMG) severity, and a clinical score higher than three were found to be independently associated with surgery .

CONCLUSION

An elevated RDW value was related to the severity of the electromyogram. RDW may, therefore, be a useful independent predictor for the decision to surgical treatment of CuTS. Level of Evidence III, Retrospective Study.

Postoperative improvement in DASH score, clinical findings, and nerve conduction velocity in patients with cubital tunnel syndrome

We investigated a recovery pattern in subjective and objective measures among 52 patients with cubital tunnel syndrome after anterior subcutaneous transposition of the ulnar nerve. Disabilities of the Arm, Shoulder and Hand (DASH) score (primary outcome), numbness score, grip and pinch strength, Semmes-Weinstein (SW) score, static 2-point discrimination (2PD) score, and motor conduction velocity (MCV) stage were examined preoperatively and 1, 3, 6, 12, and ≥24 months postoperatively. Statistical analyses were conducted to evaluate how each variable improved after surgery. A linear mixed-effects model was used for continuous variables (DASH score, numbness, grip and pinch strength), and a proportional odds model was used for categorical variables (SW and 2PD tests and MCV stages). DASH score significantly improved by 6 months. Significant recovery in numbness and SW test scores occurred at 1 month. Grip and pinch strength, 2PD test scores, and MCV stage improved by 3 months. DASH scores and numbness recovered regardless of age, sex, or disease severity. It was still unclear if both subjective and objective measures improved beyond 1-year postoperatively. These data are helpful for predicting postoperative recovery patterns and tend to be most important for patients prior to surgery.

Risk factors predicting revision surgery after medial epicondylectomy for primary cubital tunnel syndrome

BACKGROUND

Medial epicondylectomy (ME) is one of several accepted surgical options for the treatment of cubital tunnel syndrome (CuTS). Although reported outcomes after ME are generally favorable, few data exist regarding which patients are prone to poorer outcomes requiring revision surgery. The goal of this study was to identify risk factors predicting the need for revision surgery after ME for the treatment of CuTS.

METHODS

We conducted a retrospective chart review of all patients treated at our institution with ME for CuTS from 2006 through 2011. We identified patients who underwent additional operations for recurrent or persistent ulnar nerve symptoms as the revision cohort. We performed bivariate analysis to determine which variables had a significant influence on the need for revision surgery. We examined qualitative factors associated with revision, including the degree of bony resection performed during the index ME, and intraoperative findings at the time of revision surgery.

RESULTS

Revision surgery was required in 13.3% of cases (11 of 83). On bivariate analysis, younger age, associated workers' compensation claims, lesser disease severity, and preoperative opioid use were all significant predictors of the need for revision surgery. Perineural scarring and heterotopic bone formation about the elbow were the 2 most common findings at the time of revision.

CONCLUSIONS

For patients with CuTS, the risk of revision surgery after ME is higher in younger patients, patients with less severe disease, patients taking opioid medications preoperatively, and patients with associated workers' compensation claims.

LEVEL OF EVIDENCE

Level IV; Case Series; Treatment Study.

Anterior subcutaneous transposition of the ulnar nerve improves neurological function in patients with cubital tunnel syndrome

Although several surgical procedures exist for treating cubital tunnel syndrome, the best surgical option remains controversial. To evaluate the efficacy of anterior subcutaneous transposition of the ulnar nerve in patients with moderate to severe cubital tunnel syndrome and to analyze prognostic factors, we retrospectively reviewed 62 patients (65 elbows) diagnosed with cubital tunnel syndrome who underwent anterior subcutaneous transposition. Preoperatively, the initial severity of the disease was evaluated using the McGowan scale as modified by Goldberg: 18 patients (28%) had grade IIA neuropathy, 20 (31%) had grade IIB, and 27 (42%) had grade III. Postoperatively, according to the Wilson & Krout criteria, treatment outcomes were excellent in 38 patients (58%), good in 16 (25%), fair in 7 (11%), and poor in 4 (6%), with an excellent and good rate of 83%. A negative correlation was found between the preoperative McGowan grade and the postoperative Wilson & Krout score. The patients having fair and poor treatment outcomes had more advanced age, lower nerve conduction velocity, and lower action potential amplitude compared with those having excellent and good treatment outcomes. These results suggest that anterior subcutaneous transposition of the ulnar nerve is effective and safe for the treatment of moderate to severe cubital tunnel syndrome, and initial severity, advancing age, and electrophysiological parameters can affect treatment outcome.

A simple, safe and reliable surgical landmark for medial epicondylectomy

BACKGROUND

Various surgical strategies have been described for the treatment of cubital tunnel syndrome, including medial epicondylectomy. This aims to decompress the ulnar nerve and allow a 'mini anterior transposition'. The major concern over medial epicondylectomy is the potential for postoperative iatrogenic valgus instability.

METHODS

We utilized a surgical landmark for medial epicondylectomy based on the medial aspect of the ulnar nerve with the elbow in 90° of flexion in 12 cadaveric upper limbs. The size of the resultant fragment was measured and, subsequently, the medial collateral ligament was dissected and the elbow stressed to assess its integrity.

RESULTS

This technique resulted in the excision of a fragment of mean width 8 mm (range 6 mm to 11 mm) and allowed the ulnar nerve to smoothly translate anteriorly in flexion. The anterior band of the ulnar collateral ligament was macroscopically preserved in all cases and there was no valgus instability.

CONCLUSIONS

The medial border of the ulnar nerve is a simple, safe and reliable surgical landmark for medial epicondylectomy. This technique offers advantages over other described methods of assessing the location at which to perform a medial epicondylectomy.

Ulnar neuropathy at the elbow: an evidence-based algorithm

Ulnar neuropathy at the elbow is the second most common compression neuropathy of the upper extremity and poses a challenge for treating physicians. Lack of a standardized grading system, outcome measures, or surgical indications can make treatment decisions difficult to justify. Conclusions drawn from the available literature include similar rates of good to excellent outcomes for in situ decompression; transposition in the subcutaneous, submuscular, or intramuscular planes; and endoscopic decompression. Outcomes for revision surgery are generally less favorable. Development of standardized outcomes measures will be important in improving the quality and comparability of the literature on this subject.

Effect of partial, distal epicondylectomy on reduction of ulnar nerve strain: a cadaver study

PURPOSE

To compare the decrease in ulnar nerve strains using a modification of medial epicondylectomy by removing the distal half of the medial epicondyle with in situ decompression and partial medial epicondylectomy.

METHODS

Using 20 elbows of 10 fresh human cadavers, we measured the strain on the ulnar nerve using a microstrain gauge before and after in situ decompression. Then, we repeated the measurements after partial medial epicondylectomy on left elbows, and after distal medial epicondylectomy on right elbows. We compared the mean strain values with 2-way analysis of variance.

RESULTS

The decrease in mean ulnar nerve strain with in situ decompression from 5.4% to 5.2% on the right side and 5.4% to 5.0% on the left was not statistically significant. The decrease to 2.9% on the left elbows after partial and to 1.9% on the right elbows after distal medial epicondylectomy was statistically significant. In addition, the remaining ulnar nerve strain after distal medial epicondylectomy was significantly less compared with that after partial medial epicondylectomy. We observed nerve subluxation only with partial medial epicondylectomy.

CONCLUSIONS

In situ decompression alone does not change ulnar nerve strains. The significant change in ulnar nerve strain with partial or distal medial epicondylectomy underlines the role of medial epicondyle on stretching of the ulnar nerve. Excision of the distal half of the medial epicondyle sets the contact point of the nerve with the bone proximally and decreases the strain on ulnar nerve more effectively than partial epicondylectomy. However, its efficacy and complications need to be studied clinically.

CLINICAL RELEVANCE

The results of the present cadaveric study suggest that excision of the distal half of the medial epicondyle in cubital tunnel syndrome may decrease ulnar nerve strain effectively. The clinical effect of decrease in nerve strain and the indications for the procedure need to be investigated.

Distal medial epicondylectomy. A modification of partial medial epicondylectomy for cubital tunnel syndrome: preliminary results

INTRODUCTION

The medial epicondyle behaves as a fulcrum and a pulley that tethers the ulnar nerve during flexion. Excision of the distal half of the medial epicondyle sets the point of contact of the bone with the nerve proximally and decreases the traction effect of the medial epicondyle on the ulnar nerve. In this study, we aim to investigate the surgical and clinical results of excision of the distal half of the medial epicondyle in cubital tunnel syndrome (CuTS).

PATIENTS AND METHODS

Cubital tunnel release with excision of the distal half of the medial epicondyle was performed in 19 patients. The patients were evaluated preoperatively and postoperatively with clinical examinations, McGowan and Wilson-Krout scores, Semmes-Weinstein monofilament and two-point discrimination tests, and grip and pinch strength measurements.

RESULTS

A one-grade improvement in McGowan classification was observed in 79 % of patients and a two-grade improvement in 21 % of patients at the time of the first postoperative examination. At 24 months after surgery, 18 patients reported the Wilson-Krout scores as excellent (95 %). Statistically significant improvements in sensory and motor strength measurements were achieved at all postoperative examinations.

CONCLUSION

The objective and subjective outcome measures achieved with distal medial epicondylectomy are comparable with other epicondylectomy techniques. The complication rates seem to be lower than those of total or partial medial epicondylectomy. This procedure is an acceptable and safe alternative for the surgical treatment of CuTS.