Minimal-incision in situ ulnar nerve decompression at the elbow

The Unpredictable Ulnar Nerve-Ulnar Nerve Entrapment from Anatomical, Pathophysiological, and Biopsychosocial Aspects

Peripheral nerves consist of delicate structures, including a rich microvascular system, that protect and nourish axons and associated Schwann cells. Nerves are sensitive to internal and external trauma, such as compression and stretching. Ulnar nerve entrapment, the second most prevalent nerve entrapment disorder after carpal tunnel syndrome, appears frequently at the elbow. Although often idiopathic, known risk factors, including obesity, smoking, diabetes, and vibration exposure, occur. It exists in all adult ages (mean age 40-50 years), but seldom affects individuals in their adolescence or younger. The patient population is heterogeneous with great co-morbidity, including other nerve entrapment disorders. Typical early symptoms are paresthesia and numbness in the ulnar fingers, followed by decreased sensory function and muscle weakness. Pre- and postoperative neuropathic pain is relatively common, independent of other symptom severity, with a risk for serious consequences. A multimodal treatment strategy is necessary. Mild to moderate symptoms are usually treated conservatively, while surgery is an option when conservative treatment fails or in severe cases. The decision to perform surgery might be difficult, and the outcome is unpredictable with the risk of complications. There is no consensus on the choice of surgical method, but simple decompression is relatively effective with a lower complication rate than transposition.

Percutaneous ultrasound-guided ulnar nerve release technique compared to open technique: A cadaveric study

OBJECTIVES

To evaluate the outcomes of a novel percutaneous ultrasound-guided technique for release of ulnar nerve entrapment at the elbow when compared to standard open release Methods: One single surgeon performed an ultrasound-guided percutaneous release of the cubital tunnel on a group of five cadaveric elbows and open release on five others. All procedures were timed, and incision lengths were recorded. Meticulous anatomic dissection was then performed to assess the complete release of the carpal tunnel and iatrogenic injuries.

RESULTS

No significant difference was found between the two groups in terms of complete release and iatrogenic injury, whereas Operative time was significantly shorter for the US-guided technique. Incomplete releases of the nerve were found only during the first two trials in each group, while the third, fourth, and fifth trials showed a complete ulnar nerve release in both series, highlighting a fast learning curve for both techniques. All of this through a significantly smaller incision in the US-guided technique.

CONCLUSIONS

This study highlights the similar effects of these two techniques in terms of complete release of the ulnar nerve, with no clear superiority of one over the other in terms of morbidity rate. Both have a fast learning curve for an ultrasound-trained surgeon, with the US-guided technique being a less traumatic and quicker alternative procedure.

Cubital Tunnel Syndrome: Review of Diagnosis and Management

Cubital tunnel syndrome is one of the most common upper extremity nerve entrapment conditions. Clinical examination and electrodiagnostic studies assist in the diagnosis. Mild cases can be successfully treated conservatively, aiming to reduce traction and compression on the nerve. Surgical management of cubital tunnel syndrome is increasing in frequency. Multiple surgical options exist ranging from simple decompression to decompression and anterior transposition of the nerve. There is no preferred surgical technique. It is critical to reduce the risk of recurrent cubital tunnel syndrome. Revision surgical procedures have worse outcomes than primary surgical procedures.

Curved skin incision for Ulnar nerve transposition in Cubital Tunnel Syndrome: Cadaveric and clinical study to avoid injury of medial cutaneous nerve

INTRODUCTION

Medial skin incision is obligatory for ulnar nerve transposition in cubital tunnel syndrome. However, inadvertent surgical damage to the terminal branches of both the medial antebrachial cutaneous nerve (MACN) and the medial brachial cutaneous nerve (MBCN) has been a concern in the current surgical approach.

HYPOTHESIS

We hypothesized a modified curved skin incision to avoid the damage to the medial cutaneous nerve.

MATERIALS AND METHODS

The numbers and locations of MACN and MBCN terminal branches were investigated; also, the location of the posterior branch of MACN in ten fresh frozen cadaveric upper extremities. Using modified incision which is more anterior than classic approach and includes antegrade dissection of the cutaneous branches, same measurement was performed in clinical cases. We described the techniques.

RESULTS

The average number of MACN posterior terminal branches was 2.6±1.6 and 4.4±2.4 branches in the cadaveric specimens and clinical cases, respectively. The average number of MBCN terminal branches was 2.1±0.87 branches. The MACN posterior terminal branches were located at an average of 19mm proximal and 45mm distal from the medial epicondyle. In clinical cases, we could preserve all MBCN terminal branches and posterior terminal branches of MACN using the indexed skin incision.

DISCUSSION

Our modified medial skin incision technique with antegrade subcutaneous dissection exposed all the terminal branches of MACN and thus, could reduce the risk of inadvertent injury. The medial epicondyle and the basilic vein are reliable anatomical landmarks to identify the posterior branch of the MACN.

LEVEL OF PROOF

IV, Cadaveric and Therapeutic study.

Features of the Ulnar Nerve Predicting Postoperative Prognosis in Idiopathic Cubital Tunnel Syndrome: Three Distinct Features of the Ulnar Nerve

PURPOSE

This retrospective case-control study was performed to determine the relationships between features of the ulnar nerve and postoperative outcomes following in situ decompression in idiopathic cubital tunnel syndrome (CuTS).

METHODS

The study population consisted of 86 patients who had undergone surgery for CuTS. We evaluated demographic factors, hand dominance, symptom onset time, time from diagnosis to surgery, findings of electrodiagnosis (nerve conduction velocity/electromyography), and preoperative clinical status. Intraoperatively, the ulnar nerve was defined as a definitively compressed, abnormally enlarged, or inflammatory lesion. Clinical improvements were evaluated at least 2 years after surgery.

RESULTS

Fifty-four patients showed improvement after surgery in terms of the modified McGowan grade and were designated as group 1. Meanwhile, 32 patients with unchanged or aggravated status were classified as group 2. Preoperative status, as determined by the modified McGowan grade, Boston Symptom Severity Scale score, severity of electrodiagnosis, and predominant symptoms were similar between the groups (all, P > 0.05). On regression analysis, only the classification of nerve lesions and the time from diagnosis to surgery had an impact on postoperative outcome (all, P < 0.05). Especially, enlarged ulnar lesion predicted poor prognosis (P = 0.003).

CONCLUSIONS

Ulnar nerve enlargement, grossly detected intraoperatively, and long interval between diagnosis and surgery were independently associated with poor prognosis of CuTS. Among the anatomic structures involved in the generation of CuTS, the medial epicondyle showed a strong association with enlarged nerve lesions.

Comparing endoscopic and open decompression of the ulnar nerve in cubital tunnel syndrome: a prospective randomized study

BACKGROUND

Prospective randomized data is currently lacking which compares endoscopically assisted surgery with open surgical techniques in the treatment of cubital tunnel syndrome (CUTS). The aim of this study is to compare patient outcome in both techniques.

METHOD

This prospective study comprised of 45 patients who, between October 2014 and February 2017, were randomly assigned to undergo either endoscopic or open surgery (22 and 23 patients respectively) for decompression of the ulnar nerve. Patients were followed up at 3 and 12 months postoperation. McGowan classification was used to determine the severity of symptoms. Surgical outcome was evaluated by Bishop classification. Pain levels were monitored according to gender from 0 to 10 days postoperation. Other factors investigated were chronic scar pain, working status, operation duration, and patient satisfaction regarding postoperative scarring and the procedure itself.

RESULTS

Both methods are equally effective in the treatment of CUTS (Bishop score excellent or good 90% vs 96%). Postoperative pain is significant particularly in the first few days following surgery, but with no significant difference depending on procedure. In the open group, postoperative pain was significantly higher in women than in men; pain did not differ between the sexes in the endoscopic group. The tendency to lower levels of pain among endoscopically operated women in comparison with women in the open group was not statistically notable. Patients who underwent open decompression experienced notably higher levels of postoperative chronic scar pain. Although working status and satisfaction with the surgical outcome were the same in both groups, satisfaction with scarring was higher in the endoscopy group. Operation time was significantly longer by endoscopy.

CONCLUSIONS

Both studied methods produced equal satisfactory outcomes in the treatment of CUTS. Endoscopy has the potential to minimize chronic scar pain and improve scarring esthetics, at the expense of longer operating time.

CLINICAL TRIAL REGISTRATION NUMBER

Supported by Ministry of Health, Czech Republic-conceptual development of research organization (FNOs/2014, project number 20). Graphical abstract Median postoperative pain from 0 to 10 days by group.

Can We Make Simple In Situ Decompression of the Ulnar Nerve at the Elbow Still Easier?

BACKGROUND

In situ decompression and transposition are equally effective in cubital tunnel syndrome treatment. Both are traditionally performed in the supine position.

OBJECTIVE

To validate our surgical technique for in situ decompression in the lateral decubitus position, comparing results with other techniques used in our institutions.

METHODS

A retrospective study was performed from January 2009 to February 2016, of 188 patients with cubital tunnel syndrome 115 males, 73 females; mean age, 53.44 ± 12.12 years standard deviation (range, 18-84 years) treated with in situ decompression in the lateral or supine positions or transposition (subcutaneous or submuscular). The lateral decubitus group received local anesthesia and the remainder received a brachial plexus block. Clinical and electrophysiologic results between these 4 groups were compared.

RESULTS

There were no statistically significant demographic differences between groups. Results were better in in situ decompression groups compared with transpositions. Mean follow-up was 1511.1 ± 770.57 days standard deviation (range, 310-4203 days). There were no recurrences or residual elbow pain/dysesthesia/anesthetic scar/hyperesthesia/neuroma in the lateral decubitus group. Complication and recurrence rates were in direct correlation to incision size. The worst results were seen in transpositions, particularly in the submuscular group. In situ decompression in the supine position had better results than transpositions but worse than those performed in lateral decubitus. Smaller surgical wound correlates with a reduction in operating time, costs, complication rates, and time out of work.

CONCLUSIONS

In situ decompression is equally as effective as ulnar nerve transpositions but with fewer complications and recurrences. In the lateral decubitus position, the retroepicondylar tunnel is more accessible, allowing smaller incisions and better results.

Osborne's Ligament: A Review of its History, Anatomy, and Surgical Importance

When discussing the pathophysiology of ulnar neuropathy, Geoffrey Vaughan Osborne described a fibrous band that can be responsible for the symptoms seen in this disorder. In this paper, we take a glimpse at the life of Osborne and review the anatomy and surgical significance of Osborne’s ligament. This band of tissue connects the two heads of the flexor carpi ulnaris and thus forms the roof of the cubital tunnel. To our knowledge, no prior publication has reviewed the history of this ligament, and very few authors have studied its anatomy in any detail. Therefore, the aim of the present paper is to elucidate this structure that is often implicated and surgically transected to decompress the ulnar nerve at the elbow.

Minimally Invasive In Situ Cubital Tunnel Decompression

The purpose of this study is to describe a modified technique for a minimally invasive approach to in situ ulnar nerve decompression and to provide long-term follow-up. Thirty-one patients were included. DASH and MHQ scores were measured. Mean postoperative DASH score was 10. Eighty percent of patients achieved a postoperative DASH score under 10. Average postoperative MHQ scores were as follows: overall hand function 89, activities of daily living 93, work 92, pain 7, esthetics 95, and satisfaction 84. There were no postoperative neurological complications. No patient required open decompression or transposition. There were no wound complications. This technique addresses all points of possible compression, results in outcomes similar to those reported in the literature, and results in excellent cosmesis. It is a simple and safe technique that avoids the complexities of endoscopy and transposition and has proven to be successful.

Autogenous Vein Wrapping versus In Situ Decompression for Management of Secondary Cubital Tunnel Syndrome after Surgical Fixation of Elbow Fractures: Short-Term Functional and Neurophysiological Outcome

PURPOSE

The aim of this study was to compare the functional and neurophysiological outcome of in situ decompression versus in situ decompression augmented with autogenous vein wrapping in management of secondary cubital tunnel syndrome at the elbow following fixation of elbow fractures.

METHODS

A prospective comparative randomized study was performed on 29 patients who were divided into two groups: group I (in situ decompression) and group II (in situ decompression augmented with autogenous vein wrapping). We measured the patients' demographics, subjective reports of symptoms, and objective evaluation of the functional and neurophysiological outcomes of both groups.

RESULTS

Group II patients achieved statistically better results in both neurophysiological scoring and clinical sensory rating but not in all other parameters.

CONCLUSION

Autogenous vein wrapping for secondary cubital tunnel syndrome after elbow fracture fixation only provides a better sensory outcome.

LEVEL OF EVIDENCE

Level II, therapeutic prospective comparative study.

Endoscopic vs Open Decompression of the Ulnar Nerve in Cubital Tunnel Syndrome: A Prospective Randomized Double-Blind Study

BACKGROUND

Prospective randomized data for comparison of endoscopic and open decompression methods are lacking.

OBJECTIVE

To compare the long- and short-term results of endoscopic and open decompression in cubital tunnel syndrome.

METHODS

In a prospective randomized double-blind study, 54 patients underwent ulnar nerve decompression for 56 cubital tunnel syndromes from October 2008 to April 2011. All patients presented with typical clinical and neurophysiological findings and underwent preoperative nerve ultrasonography. They were randomized for either endoscopic (n = 29) or open (n = 27) surgery. Both patients and the physician performing the follow-up examinations were blinded. The follow-up took place 3, 6, 12, and 24 months postoperatively. The severity of symptoms was measured by McGowan and Dellon Score, and the clinical outcome by modified Bishop Score. Additionally, the neurophysiological data were evaluated.

RESULTS

No differences were found regarding clinical or neurophysiological outcome in both early and late follow-up between both groups. Hematomas were more frequent after endoscopic decompression (P = .05). The most frequent constrictions were found at the flexor carpi ulnaris (FCU) arch and the retrocondylar retinaculum. We found no compressing structures more than 4 cm distal from the sulcus in the endoscopic group. The outcome was classified as "good" or "excellent" in 46 out of 56 patients (82.1%). Eight patients did not improve sufficiently or had a relapse and underwent a second surgery.

CONCLUSION

The endoscopic technique showed no additional benefits to open surgery. We could not detect relevant compressions distal to the FCU arch. Therefore, an extensive far distal endoscopic decompression is not routinely required. The open decompression remains the procedure of choice at our institution.

ABBREVIATION

Dig, digitFCU, flexor carpi ulnarisNAS, numeric analog scale.

Ulnar neuropathy: evaluation and management

Ulnar neuropathy is commonly encountered, both acutely after elbow trauma and in the setting of chronic compression neuropathy. Careful clinical evaluation and discerning evaluation of electrodiagnostic studies are helpful in determining the prognosis of recovery with nonoperative and operative management. Appreciation of the subtleties in clinical presentation and thoughtful consideration of the timing and type of surgical intervention are critical to optimizing outcomes after treatment of ulnar neuropathy. The potential need for decompression at both the cubital tunnel and Guyon's canal must be appreciated. Supplementation of decompression with supercharged end-to-side nerve transfer can expedite motor recovery of the ulnar intrinsic muscles in the appropriately selected patient. The emergence of nerve transfer techniques has also changed the management of acute ulnar nerve injuries.

Predicting Revision Following In Situ Ulnar Nerve Decompression for Patients With Idiopathic Cubital Tunnel Syndrome

PURPOSE

To determine the incidence of revision and potential risk factors for needing revision surgery following in situ ulnar nerve decompression for patients with idiopathic cubital tunnel syndrome (CTS).

METHODS

We conducted a retrospective chart review of all patients treated at 1 specialty hand center with an open in situ ulnar nerve decompression for idiopathic CTS from January 2006 through December 2010. Revision incidence was determined by identifying patients who underwent additional surgeries for recurrent or persistent ulnar nerve symptoms. Bivariate analysis was performed to determine which variables had a significant influence on the need for revision surgery.

RESULTS

Revision surgery was required in 3.2% (7 of 216) of all cases. Age younger than 50 years at the time of index decompression was the lone significant predictor of need for revision surgery. Other patient factors, including gender, diabetes, smoking history, and workers' compensation status were not predictive of the need for revision surgery. Disease-specific variables including nerve conduction velocities, McGowan grading, and predominant symptom type were also not predictive of revision.

CONCLUSIONS

For patients with idiopathic CTS, the risk of revision surgery following in situ ulnar nerve decompression is low. However, this risk was increased in patients who were younger than 50 years at the time of the index procedure. The findings of this study suggest that, in the absence of underlying elbow arthritis or prior elbow trauma, in situ ulnar nerve decompression is an effective, minimal-risk option for the initial surgical treatment of CTS.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic III.

Endoscopic ulnar nerve release at the elbow: Indications and outcomes

BACKGROUND

Ulnar nerve entrapment at the elbow is the second most common nerve entrapment syndrome at the upper limp, after carpal tunnel syndrome. Many surgeons feel that ulnar nerve instability contra-indicates endoscopic nerve release. Published studies, however, found no evidence that pre-operative or intra-operative ulnar nerve instability adversely affected clinical outcomes. The objective of this prospective study was to define the indications and describe the outcomes of endoscopic ulnar nerve release at the elbow.

HYPOTHESIS

Endoscopic ulnar nerve release at the elbow is a valid option even in patients with ulnar nerve instability and regardless of the severity of the compression.

MATERIAL AND METHODS

We conducted a prospective single-centre study of patients scheduled for surgery based on clinical and electromyographic manifestations of ulnar nerve entrapment at the elbow. Ulnar nerve instability (incomplete dislocation, i.e., Childress A) before or during surgery was not a contra-indication to the procedure. The patients were re-evaluated 12 months after surgery.

RESULTS

Seventeen patients were included in the statistical analysis. The modified Bishop's score indicated excellent or good outcomes in 15 (88%) patients (excellent in 4 and good in 11) and a fair outcome in 2 patients. Functional outcomes were not associated with the presence of ulnar nerve instability before surgery.

DISCUSSION

We elected to include patients with Childress A ulnar nerve instability. Clinical outcomes in these patients were similar to those in patients without ulnar nerve instability.

LEVEL OF EVIDENCE

IV, open prospective study of treatment outcomes.

Surgical Treatment of Cubital Tunnel Syndrome: Trends and the Influence of Patient and Surgeon Characteristics

PURPOSE

To examine trends in and determinants of the use of different procedures for treatment of cubital tunnel syndrome.

METHODS

We performed a retrospective cross-sectional analysis of the Healthcare Cost and Utilization Project Florida State Ambulatory Surgery Database for 2005 to 2012. We selected all patients who underwent in situ decompression, transposition, or other surgical treatments for cubital tunnel syndrome. We tested trends in the use of these techniques and performed a multivariable analysis to examine associations among patient characteristics, surgeon case volume, and the use of different techniques.

RESULTS

Of the 26,164 patients who underwent surgery for cubital tunnel syndrome, 80% underwent in situ decompression, 16% underwent transposition, and 4% underwent other surgical treatment. Over the study period, there was a statistically significant increase in the use of in situ release and a decrease in the use of transposition. Women and patients treated by surgeons with a higher cubital tunnel surgery case volume underwent in situ release with a statistically higher incidence than other techniques.

CONCLUSIONS

In Florida, surgeon practice reflected the widespread adoption of in situ release as the primary treatment for cubital tunnel syndrome, and its relative incidence increased during the study period. Patient demographics and surgeon-level factors influenced procedure selection.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.

Ulnar nerve stability-based surgery for cubital tunnel syndrome via a small incision: a comparison with classic anterior nerve transposition

OBJECTIVE

The purpose of this study was to compare the clinical outcomes of ulnar nerve stability-based surgery via a small incision with those of classic anterior transposition of the ulnar nerve for cubital tunnel syndrome.

METHODS

From March 2008 to December 2013, 107 patients with cubital tunnel syndrome underwent simple decompression or anterior transposition via a small incision, according to an ulnar nerve stability-based decision based on an assessment of intraoperative ulnar nerve stability (group A, n = 51), or anterior transposition via a classic incision (group B, n = 56). Clinical outcome was assessed using grip and pinch strength, two-point discrimination, the mean of the disabilities of arm, shoulder, and hand (DASH) survey, and the modified Bishop scale.

RESULTS

At the final follow-up, all outcome measures improved significantly in both groups and there were no significant differences between the two groups. However, there were fewer operation-related complications in group A (one revision surgery) than in group B (one superficial infection, two painful scars, and five cases of numbness at the medial elbow).

CONCLUSIONS

Outcomes after the ulnar nerve stability-based approach and anterior transposition were similar, although more patients experienced operation-related complications after anterior transposition via a classic incision. Making an ulnar nerve stability-based decision to perform either simple decompression or anterior transposition via a small incision seems to be a better strategy for patients with cubital tunnel syndrome.