Introduction:
Neck dissection (ND) operations are performed to treat known metastatic neck illness. These operations have been associated with chronic neck and shoulder problems. In patients who have had a ND, adhesive capsulitis (AC) is one of the causes of shoulder dysfunction.

Methods:
Forty patients with AC following modified radical neck dissection (MRND) surgeries were chosen at random and divided into two groups of equal size. The low-level laser therapy (LLLT) group (group A) received LLLT with: wavelength – 830 nm, output – 50 mw, maximum frequency – 5000 Hz, pulse duration – 50 ns, and average dose – 9 J/cm² for 20 min, plus traditional physical therapy (mobilisation technique, myofascial release, range of motion (ROM), and strengthening exercises) for 30 min. The proprioceptive neuromuscular facilitation (PNF) group (group B) received PNF for 25–30 min in addition to traditional physical therapy. The treatment period was 3 times each week and lasted for eight weeks. The discomfort in the shoulder was measured using the visual analogue scale (VAS). Shoulder impairment and pain were assessed by the SPADI scale and the shoulder ranges of motion were assessed using the universal goniometer technique. All measures were taken before and after the intervention.

Results:
The findings reveal that there was a significant enhancement in all variables in both groups A and B after therapy compared to before the treatment (p < 0.001). After therapy, there were no obvious changes in the VAS and SPADI values among the groups (p > 0.05). However, statistical analysis showed significant improvement in the PNF group (group B) in shoulder flexion, abduction and external rotation in comparison to that of the LLLT group (group A) after treatment (p < 0.001).

Conclusions:
PNF proved to be more effective than LLLT in increasing ROM but was as effective as LLLT in decreasing shoulder pain and dysfunction in AC post ND surgery.