Results

Patient characteristics

Among 21 patients, 85.7% responded to the questionnaire, resulting in a total of 18 patients included into the final analysis. The median age was 39.5 years (IQR 45- 34). The majority of patients was female (71%). Comorbidities were present in 44% of patients. Hypertension was the most frequent comorbidity (present in 22% of patients), followed by diabetes mellitus (17%), hypothyroidism (17%), and obesity (11%).

Among the study participants, three patients had a history of smoking, while the majority (15 out of 18, 83%) had no smoking history. The follow-up assessment was conducted at a median of 1.7 years after the surgical intervention (IQR 0.7-3) (Table 1).

Patient number | 18
Median age in years (IQR) | 39.5 (45-34)
Sex (n) | 72% (13)
Female | 28% (5)
Male | 
Symptoms (n)Motor deficitsSensory deficits-Hypesthesia-Paresthesia-Pain (94%) | 17% (3)
100% (18)
100% (18)
56% (8)
94% (17)
Side of symptoms (n) | 17% (3)
Both | 61% (11)
Right | 39% (7)
Left | 
Median duration of symptoms before surgery in months (IQR) | 48 (96-24)
Anatomical variations (n)-Accessory cervical rib-Accessory muscle-Sibson fascia-Prolonged transverse C7 processus | 28% (5)
61% (11)
11% (2)
5% (1)
nTOS-Classification (n) | 17% (3)
nTOS 1 | 83% (15)
nTOS 2 | 0% (0)
nTOS 3 | 
Presence of comorbidities (n) | 44% (8)
Hypertension | 22% (4)
Hypothyroidism | 17% (3)
Diabetes mellitus, type II | 17% (3)
Obesity | 11% (2)
Work status (n) | 67% (12)
Absent from work | 17% (3)
Retired | 
Increased motion of upper extremities due to (n)-Work-Physical activities | 28% (5)
22% (4)
Preoperative pain medication (n) | 78% (14)
Yes | 22% (4)
No | 
Smoking history (n) | 17% (3)
BMI (IQR) | 23.4 (27.4-21.7)
Median | 23.1 (23.9-21.1)
Female | 27.7 (37.3-24.3)
Male | 

A detailed illustration of the clinical features, nTOS classification, and outcome at follow-up in our nTOS patient cohort is further demonstrated in Table 2.

Pat.-ID | Age | Gender | BMI | Length of symptoms (months) | Smoking | Pain Preop (NRS) | nTOS-class. (n1-3) | Work status preop | Age at surgery | Side | EQ-5D-5L Preop (VAS) | EQ-5D-5L Mob/SC/Act/Pain/Anx | Time of FU (months) | Pain at FU (NRS) | EQ-5D-5L at FU (VAS) | EQ-5D-5LMob/SC/Act/Pain/Anx | WorkStatus at FU
1 | 21 | F | 26.8 | 20 | No | 8 | n2 | Absent | 21 | Left | 80 | 1/4/4/3/2 | 9 | 4 | 95 | 1/2/2/2/1 | Absent
2 | 31 | F | 27.9 | 23 | No | 7 | n2 | Absent | 30 | right | 80 | 1/2/2/2/1 | 18 | 2 | 100 | 1/1/1/1/1 | Working
3 | 31 | F | 19.5 | 23 | No | 8 | n2 | Working | 31 | right | 70 | 4/4/4/4/3 | 15 | 3 | 70 | 2/3/3/3/1 | Working
4 | 37 | F | 28 | 60 | No | 9 | n2 | Retired | 37 | right | 60 | 4/3/4/4/4 | 7 | 6 | 85 | 2/2/3/2/2 | Retired
5 | 67 | F | 22.2 | 18 | No | 6 | n2 | Absent | 66 | right | 80 | 2/1/2/3/3 | 19 | 4 | 90 | 2/1/1/2/2 | Working
6 | 21 | F | 22 | 43 | No | 8 | n2 | Absent | 21 | right | 90 | 2/1/2/3/3 | 25 | 6 | 95 | 2/1/2/1/2 | Absent
7 | 45 | F | 21.7 | 34 | Yes | 9 | n1 | Working | 40 | right | 50 | 2/4/4/4/4 | 82 | 7 | 95 | 1/2/2/2/2 | Working
8 | 35 | F | 18 | 42 | No | 8 | n2 | Absent | 35 | right | 60 | 3/3/4/4/3 | 28 | 7 | 80 | 2/2/2/3/2 | Working
9 | 44 | F | 23.9 | 60 | No | 8 | n2 | Retired | 44 | right | 65 | 3/3/4/4/3 | 58 | 4 | 85 | 1/2/2/1/1 | Retired
10 | 70 | M | 23.1 | 34 | No | 7 | n1 | Absent | 70 | left | 65 | 2/2/3/4/1 | 57 | 8 | 65 | 2/2/3/4/1 | Absent
11 | 41 | M | 24.3 | 67 | No | 8 | n1 | Retired | 37 | left | 60 | 3/4/3/4/3 | 6 | 5 | 85 | 2/3/2/2/1 | Retired
12 | 69 | M | 37.7 | 54 | No | 9 | n2 | Working | 69 | left | 50 | 3/3/4/4/3 | 37 | 2 | 95 | 2/2/2/2/1 | Retired
13 | 44 | M | 27.7 | 55 | No | 8 | n2 | Absent | 54 | right | 40 | 3/3/3/4/4 | 12 | 8 | 70 | 2/2/2/2/2 | Working
14 | 54 | M | 38.1 | 28 | Yes | 9 | n2 | Working | 54 | left | 40 | 2/3/3/3/3 | 36 | 2 | 80 | 1/2/2/1/2 | Working
15 | 40 | F | 19.4 | 40 | Yes | 10 | n2 | Absent | 40 | left | 50 | 4/4/4/3/4 | 2 | 5 | 75 | 2/2/2/2/2 | Absent
16 | 34 | M | 23.5 | 34 | No | 8 | n2 | Working | 34 | left | 60 | 4/3/4/3/3 | 3 | 3 | 80 | 2/3/3/2/3 | Working
17 | 39 | M | 21.1 | 28 | No | 9 | n2 | Working | 42 | right | 65 | 4/3/3/4/3 | 2 | 4 | 80 | 2/2/3/2/2 | Working
18 | 40 | F | 23.3 | 38 | No | 3 | n2 | Absent | 40 | right | 50 | 3/4/4/2/4 | 6 | 3 | 80 | 1/1/2/2/2 | Working

Surgical outcome

In 94.4% of patients a clinical improvement was noted after surgery. Prior to surgery, the median NRS pain score was 8 (IQR 8-9) which significantly decreased at follow-up (FU), to a median pain score of 4 (IQR 3-6) (p < 0.001) indicating substantial benefit from the surgical procedure (Fig. 2 A).

Fig. 2: Surgical outcome with respect to symptom improvement. A) pre-and postoperative pain levels in patients with nTOS using the numerical ratings scale (NRS) from 0 to 10. B) Pre- and postoperative percentage of patients with hypesthesia. (***) stands for a significance level of p < 0.01.

The number of patients with hypesthesia decreased from 18 (86%) preoperatively to 7 (33%) at FU, (p < 0.01) (Fig. 2 B). The number of patients with motor deficits decreased from 3 (14%) to 1 (5%) at FU, (p < 0.01) respectively.

Quality of life

Before surgery, the median QoL score was 65 (IQR 42-80). At FU, a significant improvement to 85 (IQR 75-95) (p < 0.001) was noted, indicating a substantial enhancement in overall well-being and functional status following surgery (Fig. 3). On a scale from 1 (no problems) to 5 (inability to perform tasks) the various dimensions of patient well-being (mobility/self-care/activity/pain/and anxiety) were rated. Before surgery, median scores were 3/3/4/3/3 in the respective dimensions. At FU, all dimension ratings improved to median scores of 2/2/2/2/1, respectively (Fig. 4A–E).

Fig. 3: Quality of life (QoL) in patients surgically treated for nTOS. Comparison of preoperative QoL versus FU using a scale ranging from 0 to 100 presented by a boxplot showing the median as well as the lower and upper quartiles. (***) stands for a significance level of p < 0.01.

Fig. 4: Quality of life in patients surgically treated for nTOS. Dimensions illustrated: A) Mobility, B) Self-care, C) Activities, D) Anxiety and E) Pain. (***) stands for a significance level of p < 0.01.

Work status

Prior to the surgery, a considerable proportion of patients (68%) was absent from work. Among these, 41% were on sick leave, and 17% retired. At FU assessment, a notable reduction in work absenteeism was observed. The percentage of patients absent from work decreased to 44%, with 18% on sick leave and 23% retired (p = 0.02), resulting in an overall return to work of 14%