The shoulder's own point. Jianzhen (SI-9) sits right behind the shoulder joint and is one of the most direct, reliable points for releasing pain, stiffness and restricted movement in the shoulder — whether from an old injury, Wind-Cold invasion, or simple overuse.
Contraindications
Jianzhen (SI-9) is a straightforward and safe local point. No special contraindications are recorded in the sources; use standard clean needle technique and respect the stated depth.
Name & story
The name 肩贞 Jianzhen is often translated as "Shoulder Integrity" or "Shoulder Chastity" — both pointing to the same idea: uprightness, soundness, wholeness. It is essentially an anatomical name, marking this as the point that belongs to the shoulder itself, the one that keeps it upright and functional. When the shoulder loses its integrity — when it aches, stiffens or can no longer rise — Jianzhen is where the channel calls for attention.
Point family & character
Jianzhen (SI-9) belongs to the Small Intestine Meridian (SI), the Tai Yang channel of the arm. It is a local point on the posterior shoulder, lying just below and close to Naoshu SI-10, which is a meeting point of the Yang Motility and Yang Linking vessels. Together these two points give strong access to the entire posterior and superior shoulder region.
Five-element dynamics
The Small Intestine Meridian (SI) is a Yang channel belonging to the Fire element. Its pathway sweeps up the back of the arm, over the shoulder blade and up the neck — making it the natural channel to address the posterior shoulder and scapular region. Jianzhen (SI-9) sits right at the heart of this pathway, where Wind, Cold and Dampness most easily lodge and where Qi Stagnation and Blood Stasis accumulate after injury. By invigorating the channel here, the point restores the free flow that keeps the shoulder mobile and pain-free.
Location
Find the posterior crease of the armpit (the posterior axillary fold) with the arm hanging naturally at the side. Jianzhen (SI-9) is located 1 Cun directly above the posterior end of that crease, on the back of the shoulder joint. The nearby point Naoshu SI-10 is found by sliding a finger straight upward from SI-9 until it drops into the depression just below the scapular spine.
Anatomy & fascia
The point lies in the posterior and inferior aspect of the shoulder joint, in the soft tissue just above the posterior end of the axillary fold.
Needling
The needle is inserted perpendicularly, straight into the posterior shoulder.
Safe depth
The golden tip
For shoulder stiffness or aching at the back of the joint, try pressing or massaging the point: reach the opposite hand around and feel for the tender spot just above the back of the armpit crease. Firm, circular pressure for 1–2 minutes can help ease tension. Applying a warm pack to the posterior shoulder over this area — especially if the pain worsens with cold or damp — is a comfortable and effective home support between treatments.
For education only — not medical advice. Consult a qualified practitioner.