BL31 (Upper Bone Hole)

Location

On the sacrum at the midpoint between posterior superior iliac spine and posterior midline just at the 1st posterior sacral foramen.

Indications

Conditions for which BL31 is listed as indicated. An indication list is a reference index, not a prescription – see the protocols below for sourced treatments.

Protocols using BL31

• Back Pain, Sciatica Pain, Herniated Nucleus Pulposus – BL23, BL24, BL25, BL26, BL31, BL32, BL33, BL34, BL40, BL57, BL60, GB30 (doi:10.1093/ecam/nep085 ↗)
• Back Low Pain, Acute Pain, Referred Pain – LI04, BL29, BL30, BL31, BL32, BL40, BL54, BL58, BL62, KD03, GB30, LV03, GV03, GV04 (doi:10.1186/1745-6215-12-241 ↗)
• Fever, Anhidrosis – LU06, BL31 (doi:10.1155/2012/268237 ↗)
• Incontinence Urinary Stress, Incontinence Urinary Mixed, Incontinence Urinary Urgency – SP03, SP06, BL14, BL18, BL20, BL23, BL28, BL31, BL32, BL33, BL34, KD03, KD07, PC06, LV03, CV03, CV04, CV06, GV04, GV20 (doi:10.1136/acupmed-2015-010828 ↗)
• Urinary Retention Post-stroke, Bladder Dysfunction Incomplete Emptying – BL31, BL32, BL33, BL34 (doi:10.1186/s13063-016-1315-3 ↗)
• Spinal Cord Injury, Bladder Dysfunction Neurogenic, Urinary Retention Chronic – SP06, SP09, BL23, BL28, BL31, BL32, BL33, BL34, CV02, CV03, CV04, CV06 (doi:10.1155/2016/9245186 ↗)
• Diarrhea, Abdominal Pain, Ulcerative Colitis, Blood In Stool – BL31, BL32, BL33, BL34 (doi:10.1186/s12906-020-03101-4 ↗)
• Insufficient Lactation, Urinary Retention Postpartum, Uterine Contraction Postpartum Pain, Depression Postpartum – BL31, BL32, BL33, BL34, KD01, CV08 (doi:10.1001/jamanetworkopen.2022.13261 ↗)
• Fatigue, Nausea, Diarrhea, Waist Pain, Dysmenorrhea Primary, Menstrual Pain, Lower-abdomen Pain – SP06, BL31, BL32, BL33, BL34, CV04 (doi:10.1155/2022/1281336 ↗)
• Chronic Pain, Low Back Pain, Disability Low Back – SP06, BL23, BL31, BL32, BL33, BL60 (doi:10.1016/j.jams.2018.02.002 ↗)
• Depression Postpartum, Mood Disorder Postpartum, Anxiety Postpartum, Insomnia Postpartum, Postpartum Mood Changes – BL31, BL32, BL33, BL34, KD01, CV08 (doi:10.1159/000543477 ↗)
• Fecal Incontinence, Sleep Disturbance, Defecation Frequent, Evacuation Incomplete, Bowel Urgency – BL31, BL32, BL33, BL34, GV01 (doi:10.3389/fmed.2025.1517325 ↗)
• Fracture Coccyx, Sacrococcygeal Pain, Subluxation Coccyx, Difficulty Sitting – BL31, BL32, BL33, BL34 (doi:10.1097/MD.0000000000044068 ↗)
• Urinary Incontinence Stress, Pelvic Floor Dysfunction – ST36, SP06, BL23, BL24, BL31, BL32, BL33, BL34, BL35, CV03, CV04 (doi:10.11817/j.issn.1672-7347.2025.240242 ↗)
• Premature Ejaculation, Sexual Dysfunction – ST36, SP12, SP13, BL23, BL27, BL28, BL29, BL30, BL31, BL32, BL33, BL34, BL47, KD01, KD03, CV04, CV06 (doi:10.4103/0973-6131.113408 ↗)
• Childbirth Pain, Labor Pain – LI04, BL31, BL32, BL33, BL34, GB30, LV03 (doi:10.2147/JPR.S46693 ↗)
• Leg Pain, Leg Numbness, Leg Weakness, Radiculopathy Lumbar, Lower-back Pain – BL22, BL23, BL24, BL25, BL26, BL27, BL31, BL32, BL33, BL34, BL54, GB30, GV03, GV04 (doi:10.3831/KPI.2025.28.4.269 ↗)
• Dysuria, Urinary Frequency, Urinary Urgency, Benign Prostatic Hyperplasia, Lower Urinary Tract Symptoms – BL31, BL32, BL33, BL34 (doi:10.27465/d.cnki.gzzyc.2024.000579 ↗)
• Urinary Tract Infection, Urinary Retention, Neurogenic Bladder – ST36, SP06, BL31, BL32, BL33, BL34, BL57, KD01, CV03, CV04, CV06, CV08, GV20 (doi:10.16821/j.cnki.hsjx.2014.16.027 ↗)
• Depression Post-stroke, Urinary Retention Post-stroke – SP06, BL31, BL32, BL33, BL34, PC06, GV20 (doi:10.27026/d.cnki.ggszc.2023.000230 ↗)
• Urinary Incontinence Stress Postpartum – BL31, BL32, BL33, BL34, CV08 (doi:10.13359/j.cnki.gzxbtcm.2022.10.021 ↗)
• Urinary Incontinence Stress Postpartum – BL31, BL32, BL33, BL34 (doi:10.13359/j.cnki.gzxbtcm.2022.10.021 ↗)
• Lumbar Pain, Herniation Lumbar Disc Acute, Restricted Lumbar Mobility – ST43, BL31, BL65, GB41 (doi:10.13703/j.0255-2930.20240411-0001 ↗)
• Spinal Cord Injury, Neurogenic Bladder, Urinary Dysfunction Retention – ST36, SP06, SP09, BL23, BL28, BL31, BL32, BL33, BL34, CV03, CV04, CV06 (doi:10.16294/j.cnki.1007-659x.2020.02.006 ↗)
• Fecal Incontinence, Bowel Urgency, Bowel Dysfunction, Rectal Cancer – BL23, BL31, BL32, BL33, BL34, GV04 (doi:10.3389/fmed.2026.1815559 ↗)
• Urinary Retention, Spinal Cord Injury, Bladder Neurogenic – ST36, SP09, BL31, BL32, BL33, BL34, CV03, CV04 (doi:10.13703/j.0255-2930.20221027-k0005 ↗)
• Erectile Dysfunction – BL31, BL32, BL33, BL34 (doi:10.13703/j.0255-2930.20240924-0001 ↗)
• Incontinence Urinary Stress, Pelvic Floor Weakness – ST36, SP06, BL23, BL31, BL32, BL33, BL34, BL35, CV03, CV04, CV06 (doi:10.11817/j.issn.1672-7347.2025.240242 ↗)
• Labour Prolonged, Labour Prolonged, Labour Delayed, Labour Induce – LI04, SP06, BL31, BL32, BL60, BL67, GB21, LV03, LV05 (Deadman, Al-Khafaji & Baker, A Manual of Acupuncture — point group actions)
• Heat Bladder, Damp Bladder, Heat Bladder, Damp Bladder – ST28, SP11, SP12, HT08, BL22, BL27, BL28, BL31, BL35, BL36, BL39, KD10 (Yang Yong-Xuan, clinical point-selection notes)
• Liver Qi Stagnation, Liver Qi Stagnation – LI17, LI18, ST09, ST15, ST16, ST18, ST25, ST26, ST27, SP13, SP18, HT03, HT04, SI11, BL14, BL16, BL18, BL31, KD21, XB02T9 (Yang Yong-Xuan, clinical point-selection notes)
• Dysmenorrhea Primary – ST28, BL20, BL31, BL32, BL33, BL34, LV03 (LIU Yong-jiu, et al. cited in ZHAO Li & LI Pei. A Survey of Acupuncture Treatment for Primary Dysmenorrhea. Journal of Traditional Chinese Medicine, 2009, 29(1): 71-73)
• Leg Pain, Prolapse Of The Lumbar Intervertebral Disc, Low Back Pain – BL23, BL25, BL31, BL32, BL33, BL34, BL40, BL54 (ZHAO Bin-xiu et al. Clinical Effects of Acupuncture after Surgical Operation in Patients with Prolapse of the Lumbar Intervertebral Disc. Journal of Traditional Chinese Medicine, 2008, 28(4): 250-254)
• Sciatica, Intervertebral Disc Displacement, Sciatic Radiculopathy – BL23, BL24, BL25, BL26, BL31, BL32, BL54, GB30 (The Effectiveness of Doin (Conduction Exercise) of the Pelvic Joint for HLD With Radiating Leg Pain. ClinicalTrials.gov NCT03571503)
• PCOS, Kidney-yang Deficiency – BL31, BL32, BL33, BL34 (王任阳陈培芳夏德鹏陈燕军张雪飞高楠. 针刺结合隔姜灸八髎穴治疗肾阳虚证多囊卵巢综合征疗效观察. 亚太传统医药 ., 2023 [CNKI])

Other points on the Bladder Meridian