nyuuzyou/wikis huggingface dataset:
Post-Herpetic Neuralgia

Post-herpetic neuralgia (PHN) is a chronic neuropathic pain syndrome that occurs as a complication of herpes zoster (shingles), which is caused by the reactivation of the varicella-zoster virus (VZV). PHN is defined as pain that persists in a dermatomal distribution for at least 90 days after the onset of the herpes zoster rash. 
The pathophysiology of PHN involves nerve damage and inflammation caused by the reactivation of VZV, leading to persistent pain that can last for months to years. Risk factors for developing PHN include older age, severe acute pain during the herpes zoster episode, and severe rash. 
The most important treatment in acute Herpes Zoster is antiviral therapy within 72 hours. Management of PHN focuses on symptom control. First-line treatments include topical agents such as lidocaine and capsaicin, tricyclic antidepressants, and gabapentinoids. For refractory cases, interventional techniques are potential options but are controversial and the evidence is poor (epidural injection and pulsed radiofrequency of the dorsal root ganglion).
== Resources ==
== References ==
Category:Miscellaneous
Prepatellar Bursitis

Prepatellar bursitis is inflammation and fluid collection within the prepatellar bursa, located between the patella and the overlying subcutaneous tissue. It has been historically referred to as "housemaid's knee".Deep infrapatellar bursitis | Radiology Reference Article | Radiopaedia.org
== Pathophysiology ==
The main risk factors are compression such as repetitive kneeling and friction. However the clinician should keep in mind the possibility of an underlying rheumatological condition, especially rheumatoid arthritis and gout. Infection is another cause.
== Clinical Features ==
Anterior knee pain and swelling
== Imaging ==
Plain films may show soft tissue swelling and in chronic cases there may be clumps of calcifications.
On ultrasound there is hypoechoic fluid, and debris may be seen anterior to the patellar surface.
On MRI there is an oval shaped fluid-filled sac seen anterior to the patella. It shows up as low T1 and bright T2/fat sat signal intensity. With haemorrhage the T1 signal increases and the T2 GRE signal reduces. There may be an increased wall thickness.
== Treatment ==
Needle entry should only be done with caution due to the risk of infection and the associated morbidity with that.
Bursectomy is sometimes done in resistant cases.
== References ==
Category:Knee and Leg Conditions
Prolotherapy Injection

See Hauser et al for a free open access systematic review from 2016.The most commonly use agent is dextrose usually in concentrations between 5-20%. Some use tetradecyl (2mL 3% tetradecyl diluted in 50mL vial of prilocaine to make 0.11%) or polidocanol for those with sulfate allergies. Dextrose can be obtained by MPSO, while tetradecyl and polidocanol can be obtained from NZ scientific and medical.
== Articles ==
==References==
Category:General Procedure Concepts
Category:Stubs
Proximal Radioulnar Joint

The proximal radioulnar joint is a pivot type synovial joint between the circumference of the head of the radius and the ring formed by the radial notch of the ulna and the annular ligament.Stewart, M., Hacking, C. Proximal radioulnar joint. Reference article, Radiopaedia.org. (accessed on 01 Apr 2022) https://doi.org/10.53347/rID-53632
Category:Elbow and Forearm Anatomy
==References==
Category:Joints
Category:Joints of the Upper Limb
Quadratus Femoris Injection

==Anatomy==
The ischiofemoral space is bounded by the ischial tuberosity medially, the lesser trochanter of the femur laterally, the femoral neck, ischiofemoral ligament, and inferior gemellus muscle cranially, and the inferior edge of the quadratus femoris muscle caudally. This quadrangular muscle originates from the ischial tuberosity and attaches to the femur's intertrochanteric crest. It is innervated by the nerve to the quadratus femoris (L4-S1) and supplied by the inferior gluteal artery.
Beneath the quadratus femoris lies the obturator externus muscle, which originates from the obturator membrane and bony boundaries of the obturator foramen and inserts into the femur's trochanteric fossa. It is innervated by the obturator nerve (L3-L4) and supplied by the obturator and medial femoral circumflex arteries. Both muscles are commonly implicated in ischiofemoral impingement syndrome (IIS).
Notably, the semitendinosus, semimembranosus, and biceps femoris muscles' conjoint tendon has proximal attachments on the ischial tuberosity, and their pathologies can be difficult to distinguish from IIS. Additionally, the sciatic and inferior gluteal nerves traverse the ischiofemoral space, and their entrapment may cause sciatica-like symptoms.
==Indications and Efficacy==
Suspicion for Ischiofemoral Impingement Syndrome. The procedure can be diagnostic and/or therapeutic in nature. There are limited data on efficacy.
==Technique==
===Ultrasound Guided===
The following technique has been described:
* Patient Position: Prone
* Ultrasound Technique: use an 8-4 MHz curvilinear probe in a transverse or axial plane
** Start with ischial tuberosity as initial bony landmark
** Identify hamstring origin in soft-tissue
** Move transducer laterally to find lesser trochanter
** Note gluteus maximus muscle overlaying bony structures
** Visualize quadratus femoris muscle which lies below the sciatic nerve
** Sciatic nerve usually near and lateral to hamstring tendon origin
* Needle Approach: lateral to medial, in-plane with transducer, both laterally and deep relative to sciatic nerve
** Visualize needle tip and sciatic nerve in real time
** Place needle tip in quadratus femoris muscle
* Needle Type: 3.5-inch (8.9 cm), 22-gauge spinal needle
* Injection Solution: 4 mL, containing 1 mL of triamcinolone and 3 mL of 1% lidocaine
An obliquely oriented path with the target in the lower third of the muscle may be the safest and less painful.
===Complications===
Puncture of quadratus, sciatic and posterior femoral cutaneous nerves, and posterior circumflex artery.
==Aftercare==
Assess diagnostic response
==Videos==
https://www.youtube.com/watch?v=-UvZOsrETfY
==See Also==
==External Links==
==References==
Category:Pelvis, Hip and Thigh Procedures
Quadriceps Tendinopathy

Quadriceps tendinopathy has similar symptom provocation patterns to patellar tendinopathy. When the pain radiates it can mimic patellofemoral pain syndrome. 
It is more common in people who do jumping sports as well as in powerlifters and bodybuilders.
Under ultrasound incidental calcific changes are very common in the active population for example in cyclists.https://twitter.com/DrJN_SportsMed/status/1481970017654747141
== References ==
Category:Knee and Leg Conditions
Category:Tendinopathies
Quadrilateral Space Syndrome

Quadrilateral Space Syndrome (QSS) is a relatively uncommon disorder, initially described by Cahill and Palmer in 1983, which involves the compression of the axillary nerve and the posterior humeral circumflex artery (PHCA) within the quadrilateral space. Four distinct features of QSS were originally identified by Cahill: 
# Generalized pain in the shoulder area, 
# Nondermatomal paraesthesia, 
# Point tenderness above the quadrilateral space, and
# Angiogram results indicating positive findings when in a provocative position.
Compression can occur either at rest or during movement, and thus, QSS should be considered in patients presenting with the main symptoms of neck pain, shoulder pain, lateral arm paraesthesia, and/or quadrilateral space tenderness.
== Anatomy Pathophysiology ==
The axillary nerve supplies the teres minor and deltoid muscles, which play vital roles in abduction and external rotation. Characteristic fibrous bands can be found within the quadrilateral space, and these bands may intensify symptoms, particularly pain, triggered by movements involving the deltoid and teres minor muscles. Anatomical variations in glenohumeral joint innervation patterns among patients can complicate the process of distinguishing whether pain arises from suprascapular nerve palsy or axillary nerve compression. The PHCA wraps around the neck of the humerus, rendering it susceptible to repetitive tension and mechanical stress. This stress can lead to thrombosis and aneurysmal degeneration within the PHCA wall.
Although neurovascular compression is responsible for the acute manifestations of QSS, such as pain, paraesthesia, and muscle atrophy, there is ongoing debate as to whether the primary issue stems from neural entrapment or vascular compression.
== Clinical Features ==
QSS typically affects younger patients, who are under forty years of age and generally healthy. These individuals often have a history of engaging in repeated overhead activities, such as playing volleyball, baseball, or swimming. The presentation of symptoms in QSS can be non-specific and involve either neurogenic or vascular features. Neurogenic QSS is characterized by nonspecific patterns of paraesthesia, fasciculations, weakness, or neurogenic pain. Vascular QSS symptoms may indicate acute ischemia (pain, pallor, absent pulses), thrombosis, or embolism (coolness or cyanosis of the hand or digits). In addition to vascular and neurogenic symptoms, QSS patients can also exhibit muscular atrophy and associated weakness, which is believed to result from denervation. Tenderness over the quadrilateral space may also be present in patients.
In severe cases of QSS, thrombosis of the PHCA can obstruct blood flow from the axillary artery, leading to embolization and subsequent cyanosis, digital ischemia, and cold intolerance.
== Resources ==
Category:Shoulder Conditions
==References==
Radial Nerve Block

==Overview==
*Effective method of regional pain control of the forearm.
==Indications==
*Surgical anesthesia along the course of the radial nerve
*Postoperative anesthesia
*Radial Tunnel Syndrome
*Cheiralgia paresthetica or Wartenberg Syndrome
==Contraindications==
*Infection at the site
*Severe coagulopathy
*Allergy to local anesthetic 
==Equipment Needed==
*Alcohol/Betadine/Chlorhexidine
*Syringe, 1 mL, for local anesthetic
*Syringe, 5 mL, for nerve block
*Anesthetic - Lidocaine 1%/2%, bupivacaine 0.5%, or ropivacaine 0.5%
*Sterile Gloves
*Adhesive Bandage
==Procedure==
===Block at humerus level===
#Patient supine with arm abducted to 45 degrees and hand resting on abdomen
#Palpate deeply between the heads of the triceps muscle and brachialis muscle (musculospiral groove)
#Prepare skin with antiseptic solution
#Infiltrate injection site with 1mL of anesthetic 
#Insert a 25-gauge perpendicularly toward the musculospiral groove
#Identify the nerve by parathesia
#Aspirate to ensure you are not intravascular
#Slowly inject anesthetic
===Block at elbow level===
#Patient supine with arm abducted to 45 degrees
#Flex the elbow and identify the lateral margin of the biceps tendon at the elbow crease
#Prepare skin with antiseptic solution
#Infiltrate injection site with 1mL of anesthetic 
#Insert the needle just lateral to the tendon and advance slightly medial and cephalad towards the humerus
#Identify the nerve by parathesia
#Aspirate to ensure you are not intravascular
#Slowly inject anesthetic
===Block at wrist level===
#Prepare skin with antiseptic solution
#Infiltrate injection site with 1mL of anesthetic 
#Insert needle just above radial styloid and aim medially
#Aspirate to ensure you are not intravascular
#Slowly inject anesthetic and extend the infiltration laterally
===Ultrasound Guided===
*Please see Highland EM U/S Guide for videos and tutorials
==Complications==
*Residual Paresthesia due to intraneuronal injection
*Systemic Toxicity due to intravascular injection 
*Local Site infection
*Hematoma
==References==
Category:Elbow and Forearm Procedures
Category:Hand and Wrist Procedures
Radial Neuropathy at the Spiral Groove

Radial neuropathy at the spiral groove is also known as saturday night palsy.
==Clinical Features==
Sensory impairment of dorsal aspect of the lateral hand, part of the thumb, and proximal aspect of the dorsal 2-4 fingers. 
Muscles affected are extensor indicis, extensor digitorum communis, extensor carpi ulnaris, long head of extensor carpi radialis, supinator. The triceps are spared.
Category:Elbow and Forearm Conditions
Category:Mononeuropathies
Radiocarpal Joint

The radiocarpal joint is formed by the articulation between the distal end of the radius, a bone in the forearm, and the proximal row of carpal bones. The carpal bones involved in this joint are the scaphoid, lunate, and triquetrum. The ulna, the other bone in the forearm, is not directly involved in the joint but contributes to its stability through the triangular fibrocartilage complex (TFCC).
== Articular Surfaces ==
# Distal Radius: The distal end of the radius articulates with the proximal row of carpal bones, forming a concave surface that allows for smooth movement.
# Scaphoid: The scaphoid bone is located on the radial (thumb) side of the wrist joint and articulates with the distal radius.
# Lunate: The lunate bone is situated in the middle of the wrist joint and also articulates with the distal radius.
# Triquetrum: The triquetrum is the smallest carpal bone involved in the radiocarpal joint and is found on the ulnar (little finger) side. It does not articulate directly with the radius, but rather with the TFCC.
== Function ==
The radiocarpal joint allows for a wide range of movements, including:
# Flexion: Bending the hand toward the palmar side.
# Extension: Bending the hand away from the palmar side.
# Radial Deviation: Moving the hand toward the thumb side (radius).
# Ulnar Deviation: Moving the hand toward the little finger side (ulna).
Category:Hand and Wrist Anatomy
Category:Joints of the Upper Limb
Rotator Cuff Tendinopathy

== Treatment ==
See physiotherapy protocol by Roberta Ainsworth for massive rotator cuff tears.
==See Also==
*Subacromial Pain Syndrome
*Subacromial Bursa Injection
==Resources==
==Guidelines==
*Rotator Cuff Repair Guidelines
==References==
Category:Shoulder Conditions
Category:Tendinopathies
Sacroiliac Joint Examination

Sacroiliac Joint Provocation Tests
Sacroiliac Joint Provocation Tests	Sacroiliac Joint Provocation Tests	Sacroiliac Joint Provocation Tests	Sacroiliac Joint Provocation Tests	Sacroiliac Joint Provocation Tests	Sacroiliac Joint Provocation Tests
Test 	Sensitivity 	Specificity 	+LR 	-LR 	
3/5 Positive Tests 	0.91 	0.78 	4.16 	-0.12 	
2/4 Positive Tests (no Gaenslen) 	0.88 	0.78 	4.0 	-0.16 	
Distraction 	0.60 	0.81 	3.2 	-0.49 	
Thigh Thrust 	0.88 	0.69 	2.8 	-0.18 	
Sacral Thrust 	0.63 	0.75 	2.50 	-0.50 	
Compression 	0.69 	0.69 	2.2 	-0.46 	
Gaenslen's (R) 	0.53 	0.71 	1.84 	-0.66 	
Gaenslen's (L) 	0.5 	0.77 	2.21 	-0.65 	
==Videos==
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<youtube>szqvDYflAGw</youtube>
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<youtube>T6wq8kB2LCk</youtube>
<youtube>yWOMJKBPE0c</youtube>
<youtube>g8txpsqHYpQ</youtube>
==See Also==
Sacroiliac Joint Dysfunction
==References==
Category:Examination
Category:Sacroiliac Joint
Category:Stubs
Sacroiliac Joint Prolotherapy

Sacroiliac joint prolotherapy is sometimes used to treat sacroiliac joint pain. Protocols vary for this procedure.
==Study Protocols==
Cusi et al (RCT): Dorsal interosseous injection, done under CT guidance, for clinically diagnosed source of pain. 22-g spinal needle. 5mL syringe, 1.8mL of 50% dextrose, 2.3mL bupivacaine 1%, 0.8mL iopamidol contrast. 0.8mL injected into the ligament as it moves up and down the ligament. 
Kim et al (RCT): Intraarticular injections. 25% dextrose solution, done by diluting 50% dextrose in bupivacaine.
Hoffman et al (Retrospective cohort): 15% dextrose in lidocaine monthly three times.
== References ==
Category:Pelvis, Hip and Thigh Procedures
Category:Sacroiliac Joint Procedures
Category:Stubs
Sacroiliac Pain Maps

Sacroiliac Joint Pain can have a variable distribution. Buttock, PSIS pain is present in 94%, lower lumbar pain in 72%, groin pain in 14%, lower extremity pain in 28%, upper lumbar in 6%, abdomen in 2%, and foot in 12%. 
==Sacroiliac Posterior Ligament Pain==
The pain pattern from sacroiliac ligaments depends on which ligamentous section is involved. Patients in this study were diagnosed with sacroiliac joint dysfunction with a fluoroscopically guided periarticular SIJ injection with a >70% relief of pain. This built on their previous work.
File:Aizawa sections.PNG|Sacroiliac sections
File:aizawa section 0.png|Section 0 map
File:aizawa section 1.png|Section 1 map
File:aizawa section 2.png|Section 2 map
File:aizawa section 3.png|Section 3 map
Images Copyright © 2020 Springer Nature Switzerland AG
==Sacroiliac Joint Pain==
Pain maps from double diagnostic fluoroscopically guided intraarticular sacroiliac joint blocks, showing pain maps for responders vs non-responders. The referral pain areas were the same in both groups, but the intensity maps showed differences in pain referral at the buttock in areas overlying the SIJ (100% of the responders vs 80% of the nonresponders) and the ischial tuberosity(10% of the responders vs 100% of the nonresponders). Patients included if pain below L5 over one SIJ, with or without leg pain; several exclusion criteria.
Image Copyright © 2006 by National University of Health Sciences
==References==
Category:Pain Maps
Category:Sacroiliac Joint
Category:Stubs
Sacrum

The sacrum usually has five fused sacral vertebrae. However variations are common such as lumbarisation of S1, sacralisation of L5, fusion of the coccyx, and spina bifida (see Transitional Vertebral Anatomy). The sacrum is wedge shaped with concave anterior and convex posterior surfaces.
== Gross Anatomy ==
===Anterior Aspect===
There is a central mass that is formed by the fused vertebral bodies. This is the floor of the sacral canal. The central mass runs laterally until the four anterior sacral foramina. 
The ventral rami of S1-S4 pass through the foramina. 
===Posterior Aspect===
The posterior convex arch is formed by the fused vertebral arches. This is the roof of the sacral canal. 
There are four posterior sacral foraminae opposite to the anterior foramina where the posterior rami of S1-S4 run. S5 runs between the termination of the sacrum and the coccyx. 
There is a median crest that runs down to the sacral hiatus where there are cornuae on each side. The sacrococcygeal ligament covers the sacral hiatus posteriorly. 
===Lateral Aspects===
The lateral mass reduces in size as it goes distally giving the sacrum its triangular shape. It joins with the ilia forming the sacroiliac joints.
The cranial aspect of the lateral masses form wings called alae on either side. These are crossed by the lumbosacral trunk, L4 and L5.
===Sacral Canal===
The dural sac typically terminates at S2 but can run more distally especially in children. Below the dural sac in the sacral canal there is extradural fat, vertebral venous plexus, lower sacral nerve roots, and the filum terminale.
The mean AP diameter of the sacral hiatus is 4.6 ± 2 mm to 6.1 ± 2.1 mm, and decreases with age.
Tarlov cysts can be found below the S3 level.
===Sacral Hiatus===
This is a triangular gap on the posterior aspect of the caudal end of the sacrum. The hiatus arises due to failure of fusion of the lamina of the S5 segment. It is called spina bifida occulta when the defect is large.
On the lateral aspects of the hiatus are the margins of the deficient S5 laminae. Inferior to these are the sacral cornuae. The sacral cornuae are found about 5cm above the tip of the coccyx at the upper end of the natal cleft.
The S5 body is found anterior to the sacral hiatus. 
The 1-3mm thick sacrococcygeal ligament covers the sacral hiatus. It runs from the cornua to the coccyx. Overlying the ligament is subcutaneous fat and skin.
== Articulations ==
* Sacrococcygeal Joint
* Sacroiliac Joint
* Lumbosacral: L5/S1 intervertebral disc, and L5/S1 zygapophysial joints.
== Muscles ==
* Iliacus: anterosuperiorly
* Piriformis: anteroinferiorly
* Erector spinae: posteriorly
* Gluteus maximus: posteriorly
* Coccygeus 
==See Also==
*Coccyx
*Sacroiliac Joint
*Caudal Epidural Steroid Injection
*Tarlov Cysts
== References ==
Category:Bones
Category:Bones of the Spine
Saddle Joint

A saddle joint is an articulation between two bones that are saddle-shaped, or concave in one direction and convex in another. It is a type of Synovial Joint. This type of joint is biaxial, and one example is the first carpometacarpal joint between the trapezium (carpal) and the first metacarpal bone of the thumb. This arrangement permits the thumb to flex and extend (within the plane of the palm) as well as abduct and adduct (perpendicular to the palm). This dexterity gives humans the characteristic trait of “opposable” thumbs. 
== List of s ==
== References ==
Category:Joint Types
Sagittal Balance of the Spine

Sagittal balance forms part of the plain radiographic assessment of spinal deformity including kyphotic or lordotic deformities and scoliosis.
== Usage ==
There are numerous ways of assessing this, using various bony landmarks and angles to evaluate whether or not a normal distribution of weight and stresses is present through the axial skeleton, some incorporating the position of the head, while others focussing on the pelvis, have been described 1,2:
* C7 plumb line
* sagittal vertical axis
* chin-brow vertical angle
* kyphosis tilt angle 
* pelvic incidence
* pelvic tilt
* sacral slope
* spinopelvic angle
* spinosacral angle
Whilst many methods exist to assess sagittal balance, an abnormal plumb line (in either direction) is predictive of higher rates of micromotion and dysfunction after solid fixation ref as well as adjacent level disease 4.
== Measurement ==
=== C7 plumb line ===
One of the simplest and most widely used methods is performed on lateral standing full-length films and requires a vertical line (plumb line) drawn from the middle of the body of the C7 vertebral body. This line should pass through the superior endplate of S1, or more precisely within 2 cm (some use 1.7 cm) of the posterosuperior corner of the S1 vertebral body 1,2.
The position of this line is can be positive, neutral or negative:
* positive balance: the plumb line passes more than 2 cm in front of the posterosuperior corner of the S1 vertebral body 
* neutral balance: the plumb line passes within 2 cm of the posterosuperior corner of the S1 vertebral body
* negative balance: the plumb line passes more than 2 cm behind the posterosuperior corner of the S1 vertebral body
== Clinical Implications ==
A positive sagittal balance in the lumbar spine is associated with low back pain. (see discussion on page Idiopathic Scoliosis). However a positive balance in the cervical spine is of less importance than commonly thought (so called "head forward posture" or "loss of lordosis"). There is an increased risk of posterior disc herniation only, but there is no correlation with future clinical symptoms over 10 years.Okada E, Matsumoto M, Ichihara D, Chiba K, Toyama Y, Fujiwara H, Momoshima S, Nishiwaki Y, Hashimoto T, Ogawa J, Watanabe M, Takahata T. Does the sagittal alignment of the cervical spine have an impact on disk degeneration? Minimum 10-year follow-up of asymptomatic volunteers. Eur Spine J. 2009 Nov;18(11):1644-51. doi: 10.1007/s00586-009-1095-5. Epub 2009 Jul 17. PMID: 19609784; PMCID: PMC2899405.
== See Also ==
* See Huec et al for a free open access article on this topic, from an orthopaedic surgery perspective. 
* Coronal Balance of the Spine
==References==
Category:General Spine