Sacroiliac Joint Dysfunction.pptx

si joint dysfunction

1. Sacroiliac Joint Dysfunction Dr Bharat Timilsina Spine fellow 1 st year

2. Sacroiliac Joint Dysfunction is a degenerative condition of the sacroiliac joint resulting in lower back pain Hidden cause of low back pain

3. Goals EPIDEMIOLOGY ETIOLOGY ANATOMY Clinical PRESENTATION Diagnostic modality TREATMENT

4. EPIDEMIOLOGY Incidence : - up to 15% to 30% of cases of lower back pain in the outpatient setting Risk factors previous lumbar spine fusion especially when there is >3 levels involved   considered analogous to adjacent segment disease pregnancy and vaginal delivery previous trauma to the pelvis prior iliac crest bone graft harvesting

5. ETIOLOGY Pathophysiology:- 1) idiopathic :- the most common believed to be a result of repetitive trauma to the SI joint can begin insidiously or acutely pain is hypothesized to be generated from ligamentous/capsule tension extraneous compression or shear forces hypomobility or hypermobility increased levels of estrogen or relaxin during third trimester of pregnancy leading to hypermobility of the SI joint aberrant joint mechanics myofascial or kinetic chain imbalances inflammation

6. Pathophysiology contd : intra-articular mechanisms arthritis inflammation and degeneration of the SI joint occurs in nearly 100% of patients with spondyloarthropathies ankyklosing spondylitis Reiter's syndrome results in subchondral sclerosis, subchondral cyts , osteohytes , joint space narrowing, intra-articular gas and ankylosis

7. intra-articular mechanisms 2) Infection usually the result of hematogenous spread typically unilateral involvement organisms: Staphylococcus aureus Pseudomonas aeruginosa Cryptococcus organisms Mycobacterium tuberculosis predisposing factors: immunosuppression endocarditis IV drug abuse

8. Pathophysiology:- intra-articular mechanisms 3) Metabolic leads to early degeneration of the joint diseases: calcium pyrophosphate crystal deposition( cppd - abnormal deposit of cppd crystal in cartilage assoicated with hyperparathyridism / hypophospatimia / hypothyroidsm gout Ochronosis ( Alkaptonuria –rare genetic dis. Homogenestic oxidase is difficient –blue black discoloration of skin an cartilage hyperparathyroidism renal osteodystrophy (metabolic bone disease-seen in CRF) acromegaly

9. Pathophysiology:- intra-articular mechanisms Tumors primary very rare for SI joint most common types: giant cell tumor synovial villoadenomas chondrosarcomas secondary (metastatic) most common pelvis accounts for 40% of all oseous metastasis (2nd to spine)

10. Pathophysiology: extra-articular mechanisms ethesopathy inflammation of the ligamentous attachements to the SI joint frequently occurs with spondyloarthropathies more frequently the posterior ligaments insufficency fractures osteoporotic fractures in elderly patients repetitive trauma in athletes and military recruits post-traumatic more common after lateral compression pelvic ring injuries

11. ANATOMY Osteology   articulation of the ilium and the sacrum largest axial joint in the body considered synovial even though the superior 75% is not synovial joint surface area of 17.5 cm^2 articular surface changes with age flat until puberty by age 30 ridges form on the the iliac articular surface synovial surface begins to erode by age 50 ankylosis is common in men by age 50

12. Muscles gluteus maximus has fibrous extensions that attach to the anterior and posterior joint capsule has attachments into the sacrotuberous ligament Origin:- Ilium,scrum & coccyx Insertion :- Iliotibial tract and GT gluteus medius :- O :- gluteal surface of ilium I: - lat. Aspect of GT erector spinae :- O: - Lumabr and Lower thoracic region I:- upper thoracic and cervical region latissimus dorsi :- O: - spinous process of T7-12, Thoraco Lumbar fascia , iliac crest,inf . 3-4 ribs inf angle of scapula I:- floor of intertubercular grove of humerus biceps femoris :- O:- Iscial tuberosity & short head from linea aspara of femur : Insertion :- lat. Head of fibula has attachments to the sacrotuberous ligament oblique and transverse abdominus :- O: - costal margin,TL fascia, iliac crest and inguinal ligament Insertion: - linea alba, pubic symphysis & xyphoid process

13. Ligament anterior joint capsule and ligaments are relatively thin posterior interosseous ligament forms the posterior border of the joint capsule there is usually a rudimentary or absent posterior joint capsule sacrotuberous ligament attaches from the anterior sacrum and SI joint to the ishcial tuberosity sacrospinous ligament attaches from the anterior sacrum and SI joint to the ischial spine

14. Innervation anterior innervation L2-S2 ventral rami and sacral plexus posterior innervation L4-S4 dorsal rami Predominiently innervated by post. Rami of S1-2 & occ S3 lateral branch & associated dorsal ligament but rarely by S4 root

15. Biomechanics SI joint functions as a  triplanar shock absorber dissipates loads of the upper trunk and faciliates parturition can withstand a medial directed load six times greater than the lumbar spine fails in 1/20th the axial load of the lumbar spine sacral compression with weightbearing results creates "keystone in arch" effect muscles with fibers perpendicular to SI joint also generate compression loss of SI joint motion hinders ability to dissipate forces Types of arch in body eg : Talus:- Keystone in med. Long. Arch of foot Cuboid : in lat. Longitiudnal arch Intermediate cuniform :- transverse arch of foot Capitate :- in carpal arch of hand

16. complex motion at the SI joint: gliding rotation tilting nodding ( nutation ) most common form of motion described as the backward rotation of the ilium on the sacrum counternutation is the forward rotaton of the ilium on the sacrum translation joint motion is limited to <4° of rotation and 1.6 mm of translation motion of the joint progressively decreased with age age 40-50 for men greater than 50 for women

17. PRESENTATION Symptoms pain patterns pain usually present just inferior to the posterior superior iliac spine frequent pain referral area of other spine pathologies only 4% of patients will complain of pain above L5 can radiate past the knee and into the foot wearing a tight fitting belt may improve symptoms

18. Physical exam inspection patients may have an antalgic gait palpation identify focal areas of tenderness sacral sulcus  (most tender location)  posterior superior iliac spine (second most tender location)  motion evaluate hip and knee for underlying pathologies neurovascular in isolated SI joint dysfunction patients are neurovascularly intact pain-inhibited weakness may be present Dematomal pattern study by : slipmann at all shoes the distirbution of symptoms as showen in pic .

19. provocative tests based on a battery of tests, no single test has 100% diagnostic accuracy  >3 positive tests is highly suggestive of the diagnosis Patrick's test (FABER)  also called flexion, abduction and external rotation test (FABER) patient will report pain in the SI joint with this maneuver groin pain suggests iliopsoas tendonitis or internal hip pathology Fortin's finger test  considered positive if patient localizes pain twice to region inferomedial to PSIS Gaenslen's test  performed with the affected side hip extended off examination table and unaffected side hip and knee flexed and held by patient shearing across SI joint causes pain

20. 4) SI compression test  performed with patient laying lateral on exam table medial directed force applied over the iliac crest on the affected side reproduction of pain is considered positive 5) anterior sacral thrust test  performed with patient positioned prone on the examination table anteriorly directed force is applied to the sacrum test is considered positive if pain is reproduced in the SI joint 6) SI distraction test  with the patient supine on the examination table a posteriorly directed force over the ASIS test is considered positive when pain is reproduced in the SI joint 7) straight leg raise  used to detect radiculopathy due to herniated disc usually negative in setting of SI joint dysfunction may be positive if leg brought above 60° of elevation caused by increased SI joint motion at this level of elevation Pelvic torsion test :-

21. Associated conditions Genetics HLA-B27 associated with  ankylosing spondylitis Associated conditions orthopaedic conditions lumbar spinal fusion post-traumatic arthritis metastatic tumors medical conditions & comorbidities anklyosing spondylitis gout pseudogout infections

22. IMAGING Radiographs recommended views :- AP , lateral, internal oblique, external oblique, inlet, and outlet views of the pelvis to rule out other pelvic pathology :- flamingo views Indicated when there is suspicion of pelvic instability alternating single leg standing films of the pelvis SI joint views  AP, lateral, flexion and extension views of the lumbar spine:- to identify other spinal pain generators findings joint space narrowing subchondral sclerosis subchondral cysts osteophytes ankylosis sensitivity and specificity :- up to 25% of asymptomatic patients over the age of 50 will have abnoraml SI joints in radiographs

23. IMAGING CT :- indications has poor diagnostic power compared to SI joint injections deformity correction or surgical intervention is planned views pelvis and sacrum sagittal and coronal views 3D reconstructions MRI :- indications done to exclude other diagnoses identification of tumors, infectious process, or soft tissue components

24. IMAGING Bone scan indications studies have reported on the predictive power of SI joint pathology with SI joint injections sensitivity and specificity specificity - 90 %(identify individual With disease + ve ) sensitivity - 12 % (identify person who has no disease) positive predictive value - 86 %(person who is + ve and has disease) negative predictive valuae - 72 %( person who is – ve has no disease)

25. DIFFERENTIAL Key differential (top 5) lumbar spinal stenosis  degenerative disc disease hip osteoarthritis  hip labral tear  lumbar disc herniation  

26. TREATMENT Nonoperative :- oral medication, physical therapy, pelvic belt, and prolotherapy Indications :- first line of treatment modalities oral medications mainly involve NSAIDS to reduce inflammatory process associated with pain opioid medications should be used sparingly minimum of 4 week of non-operative modalities trial before proceeding with SI joint injection physical therapy +/- hot/cold therapy treatment focuses on addressing core muscle strengthening, proprioception , and flexibility to correct lumbopelvic and hip biomechanics

27. TREATMENT pelvic belt belt that applies medial directed force on greater trochanters   4 to 8 inch wide belt that is applied around the greater trochanters external device that mimics the function of ligaments limits the motion and shear forces across the SI joint by providing compression prolotherapy (controversial) phenol or glucose-based solutions (15% dextrose )injected at the base of ligamentous complexes to induce scarring generates inflammatory response resulting in fibroblastic migration and resultant scar that stabilizes joint (chemical Neurolysis :- rarely used- alcohole -30%-100%(95%ethyl alcohol) Painful paresthesia and formation of neuroma is complication so rarely used.

28. outcomes most effective in the acute phase of pain pelvic belt more effective for SI joint pain following pregnancy prolotherapy more effective in the setting of ligamentous laxity

29. SI joint corticosteroid injections indications second line of treatment outcomes 60% success rate in pain relief at 6 months >75% reduction in SI joint pain following a single injection is confirmatory of the diagnosis  >50% reduction in SI joint pain following two injections lower success rate in patients with previous lumbar fusion

30. radiofrequency ablation indications third line of treatment technique targets lateral branches of the sacral nerve roots Types: Thermal (tem. 42*)/ Pulsed/Cooled RF(better, less neuroma chances) outcomes efficacy is limited due to the inability to denervate the anterior neural structues of the SI joint

31. Others treatment modality Hylourenic Acid: for joints lubrication; decrease friction on joints+ mixed with steroid PRP + Local+ steroid: Local+ steroid: immediate acction PRP long action Bone marrow mesenchymal stem exosomes :- ( could relieve pain of OA via abrogation of aberrant CGRP-positive nerve and abnormal H-type vessel formation in the subchondral bone of SI joints) membrane-umbilical cord and sarapin ( plant-derived suspension obtained by Sarraceniaceae pupurin , and acts on pain pathways by obliterating the potential of C- fibers )

32. Operative open SI joint arthrodesis indications confirmed diagnosis of SI joint dysfunction as primary pain generator poor response to nonoperative treatment options patients with aberrant SI anatomy, sacral dysmorphism , or revision surgery previously infection was the only indication for arthrodesis outcomes new literature with favorable outcomes in appropriately selected patients

33. minimally Invasive SI joint arthrodesis indications confirmed diagnosis of SI joint dysfunction as primary pain generator poor response to nonoperative treatment normal SI joint anatomy outcomes vs. open shorter hospital stay smaller incision theoretical decrease in surgical site infections decreased limitation of postoperative weight bearing quicker return to full weight bearing than open arthrodesis decreased blood loss

34. TECHNIQUES SI joint corticosteroid injections technique performed under fluoroscopy or ultrasound guidance studies have shown that without imaging the injection is in the SI joint only 22% of the time can be used as both a diagnostic and therapeutic injection no more than 3 injections in a 6 month prior or 4 injections in 1 year Due to short lived life of steroid repeat injection required; works for about 6 months Radiofrequency ablation technique targets lateral branches of the sacral nerve roots dorsal nerve ramus ablation L5-S3 dorsal rami innervate SI joint Nerve Regeneration & ant. Ramus not blocked- works 9-12 months Open SI joint arthrodesis approach performed through posterior approach (anterior is limited by vital neurovascular structures) technique cartilage is removed and bone graft is packed into the obliterated space stabilized with posterior plate and screws, iliosacral screws, or cage construct made protected weight bearing for 12 weeks following surgery

35. Minimally invasive SI joint arthrodesis approach percutaneous placement of implants technique newer techniques involve triangular titanium porous coated implants "fusion" occurs by bone growth onto the implant rather than direct fusion of the joint requires multiple implants placed across SI joint to achieve stability complications patients with a dysmorphic sacrum have a higher risk of iatrogenic nerve injury

36. COMPLICATIONS Surgical site infections risk factors immunocompromised smoking diabetes Wound complications risk factors open surgical technique (wound is located in the dependent position) Nerve injury risk factors minimally invasive technique sacral dysmorphism injury to the L5, S1, or S2 nerve roots Pseudoarthrosis occurs in up to 5% of cases revision arthrodesis with open surgical technique

37. PROGNOSIS Natural history of disease quality of life of patients with SIS is more affected than patients with chronic obstructive pulmonary disease and mild heart failure equivalent to patients with hip and knee arthritis