Experience of endoscopic transcapsular axillary nerve decompression: а series of clinical cases

Background: Posttraumatic axillary nerve neuropathy is a widely spread pathology, more often seen after a shoulder joint trauma. It can also appear as a complication after orthopedic surgeries, for example, after the Latarjet procedure for shoulder stabilization. The technique of open axillary nerve decompression is very popular but has a number of disadvantages: a large trauma of soft tissue, severe bleeding, a high rate of complications, and also a poor cosmetic effect. The endoscopic surgical technique of decompression is an effective and less traumatic alternative to open procedures.

Clinical case description: We present the results of endoscopic transcapsular axillary nerve decompression in 5 patients with a clinical picture of neuropathic pain syndrome, hypoesthesia in the deltoid area, hypotrophy of the deltoid muscle, who were operated from 2018 to 2021. The mean age of patients was 44.4±14.9. An original surgical technique of decompression was developed and applied to all the patients which included arthroscopy of the shoulder joint with diagnostic and treatment components and transcapsular endoscopic axillary nerve decompression in the beach-chair position. The statistical analysis was performed using the Mann–Whitney U test. According to the VAS-scale, the severity of pain syndrome before the surgery was 6±4.6 points, while 6 months after the surgery it decreased to 1.4±0.5 points (p <0.05). According to the DASH scale, the function of the shoulder joint before the surgery was 77.6±6.9 points, and 6 months after surgery it increased to 12±5.2 points (p <0.05). According to the BMRC scale (M0–M5), the strength of the deltoid muscle before the surgery was 2±0.4 points, and after the surgery it increased to 4.4±0.5 points (p <0.05). The range of motion in the shoulder joint was as follows: before the surgery — flexion 107±45.6°, extension 102±49°, external rotation 22±13.6°; 6 months after the surgery — flexion 154±25.6°, extension 156±22.4°, external rotation 50±8° (p <0.05). The thickness of the middle portion of the deltoid muscle according to the US was 7.2±1.04 mm before the surgery, 11.8±1.44 mm after the surgery (p <0.05). All the patients (100%) at a long-term follow-up noticed complete relief of pain and regression of the neurological symptoms.

Conclusion: The achieved results allow us to characterize the method of endoscopic transcapsular decompression as a reproducible, minimally invasive and highly effective technique, providing pain relief to patients, curing neurological and intraarticular pathology, thus promoting early restoration of the upper limb function in the treated group of patients.