Pick a classification on the left and it opens on the right. This page holds the adult elective classifications. Turn on Test me to hide each answer until you tap Show answer, or press Random for a quick quiz. Each entry links to the page it comes from.
| Basis | Types |
|---|---|
| Mechanism | Traumatic, atraumatic, laxity, overuse |
| Direction | Unidirectional, anterior (98%), posterior (2%), inferior (luxatio erecta) Multidirectional, anterior/inferior, posterior/inferior, anterior/posterior/inferior |
| Chronology | Congenital, acute, chronic, locked, recurrent |
| Volition | Involuntary, voluntary |
| Degree | Subluxation, dislocation |
Posterior glenohumeral instability
| Basis | Groups |
|---|---|
| Direction | Unidirectional, posterior (smallest group) Bidirectional, posterior & inferior Multidirectional |
| Cause | Traumatic Atraumatic Acquired (baseball pitching & swimming strokes) |
| Volition | Voluntary Involuntary |
Stanmore (shoulder instability)
| Type | Description |
|---|---|
| 1 | Traumatic structural |
| 2 | Atraumatic structural |
| 3 | Muscle patterning, non-structural |
Snyder and Maffet (SLAP lesions)
| Type | Description | Frequency |
|---|---|---|
| 1 Frayed | Fraying & degeneration of superior labrum. No detachment of labrum or biceps | 11% |
| 2 Detached | Superior labrum & attached biceps tendon stripped off glenoid. Differentiate from normal anatomy, as articular cartilage of glenoid normally extends to the attachment of labrum | 41% |
| 3 Bucket handle tear of superior labrum | Displacement of central rim of labrum into joint. Peripheral labrum & biceps tendon attached to glenoid | 33% |
| 4 Bucket handle involving biceps | Bucket handle tear of superior labrum with extension into biceps tendon, which remains attached but with partial tear |
Original publication Snyder SJ, Karzel RP, Del Pizzo W, Ferkel RD, Friedman MJ. SLAP lesions of the shoulder. Arthroscopy. 1990;6(4):274-9.
| Type | Description | Treatment |
|---|---|---|
| 5 Labral tear + SLAP (extension of type 2 further down labrum) | Anteroinferior Bankart lesion extending superiorly to separate the biceps anchor | Bankart repair extended superiorly to repair the biceps anchor |
| 6 Superior flap tear (like parrot-beak tear of meniscus) | Unstable anterior or posterior flap of superior labrum with biceps anchor separation | Flap debridement and repair of the biceps anchor |
| 7 Capsular tear + SLAP | Biceps anchor separation extending anteriorly beneath the MGHL | Superior labral repair and repair of the MGHL |
Neer (impingement stages)
| Stage | Description | Age |
|---|---|---|
| I | Reversible. Oedema & haemorrhage | < 25 years |
| II | Irreversible change. Fibrosis & tendonitis IIA no tear IIB partial thickness tears | 25-40 years |
| III | Chronic. Partial & full thickness tears | > 40 years |
Original publication Neer Cs 2nd. Anterior acromioplasty for the chronic impingement syndrome in the shoulder: a preliminary report. J Bone Joint Surg Am. 1972;54(1):41-50.
Neer (rotator cuff tears)
| Group | Description |
|---|---|
| 1 | Traumatic tears. < 5% of 340 cases. < 40 years of age and result of microtrauma from overhead sports |
| 2 | Tears with dislocations. Anterior dislocation, > 40 years and in rotator interval. Multidirectional instability. Cleft tear of rotator interval. Extreme violence at any age with large cuff tear, maybe associated nerve injury |
| 3 | Impingement tears. > 40 years. 50% no history of injury |
Uhthoff (calcific tendinopathy)
| Stage | Description |
|---|---|
| Pre-Calcific stage | Fibrocartilaginous Metaplasia |
| Calcific Stage | ~No pain or chronic pain ~”Chalk” appearance ~Well-defined calcification on XR |
| Formative Stage | |
| Resting Phase | No pain or chronic pain |
| Resorptive Stage | ~Acute pain ~”Toothpaste & quot ~Fluffy appearance on XR ~Macrophage resorption |
| Post-Calcific Stage | Area heals to scar |
Frozen shoulder stages
| Phase | Features | Duration |
|---|---|---|
| Freezing | Gradual diffuse onset shoulder pain, lateral to arm at deltoid insertion. Worse at night & lying on that side. If reduce movement the pain reduced | Variable, 2-9 months |
| Frozen | Slowly progressive loss of shoulder movement with gradual subsidence of pain. Affects ADLs usually. Usually characteristic loss of ER & abduction. 10% have negligible glenohumeral movement | 4-12 months |
| Thawing | Gradually regain shoulder movement. Slow ↑ in movement with loss of discomfort | 6-9 months to regain functional ROM |
Walch (glenoid morphology)
| Type | Description |
|---|---|
| A1 | Central minor erosion, centred head |
| A2 | Central major erosion, centred head |
| B1 | Posterior narrowing and subluxation without bony erosion |
| B2 | Biconcave glenoid with posterior erosion |
| B3 | Monoconcave posterior erosion with retroversion and posterior subluxation |
| C | Excessive dysplastic retroversion |
| D | Glenoid anteversion or anterior subluxation |
Original publication Walch G, Badet R, Boulahia A, Khoury A. Morphologic study of the glenoid in primary glenohumeral osteoarthritis. J Arthroplasty. 1999;14(6):756-60.
Mayo (rheumatoid elbow)
| Grade | Description |
|---|---|
| I | Synovitis with normal radiographs |
| II | Joint space narrowing with preserved architecture |
| III | Altered architecture |
| IV | Gross destruction |
Minami (capitellar OCD)
| Grade | Description |
|---|---|
| I | Translucent shadow in mid capitellum |
| II | Clear zone between lesion and adjacent bone |
| III | Loose body |
Palmer (TFCC tears)
| Class | Description |
|---|---|
| 1 | Traumatic |
| 2 | Degenerative |
Original publication Palmer AK. Triangular fibrocartilage complex lesions: a classification. J Hand Surg Am. 1989;14(4):594-606.
Eaton and Littler (thumb CMC arthritis)
| Stage | Radiographic features |
|---|---|
| I | Normal or widened joint |
| II | Osteophytes under 2 mm |
| III | Osteophytes 2 mm or more and sclerosis |
| IV | Scaphotrapeziotrapezoid (STT) involvement |
Original publication Eaton RG, Littler JW. Ligament reconstruction for the painful thumb carpometacarpal joint. J Bone Joint Surg Am. 1973;55(8):1655-66.
SLAC wrist (Watson)
| Stage | Arthritis |
|---|---|
| I | Radial styloid and scaphoid |
| II | Entire radioscaphoid joint |
| III | Capitolunate joint |
| IV | Pancarpal arthritis including the radiolunate joint |
Original publication Watson HK, Ballet FL. The SLAC wrist: scapholunate advanced collapse pattern of degenerative arthritis. J Hand Surg Am. 1984;9(3):358-65.
SNAC wrist
| Stage | Arthritis |
|---|---|
| I | Radial styloid and distal scaphoid fragment |
| II | Scaphocapitate joint |
| III | Capitolunate joint, with the proximal pole articulation usually preserved |
Original publication Vender MI, Watson HK, Wiener BD, Black DM. Degenerative change in symptomatic scaphoid nonunion. J Hand Surg Am. 1987;12(4):514-9.
Lichtman (Kienbock disease)
| Stage | Findings |
|---|---|
| 1 Normal | No radiographic changes. May be possible to see on MRI |
| 2 Sclerosis | Density changes. Sclerosis of proximal pole |
| 3A Fragmentation | May be evidence of compression fracture. Radiolucent or radiodense line |
| 3B Collapse | Collapse of lunate. Flattening |
| 4 Degeneration | Pancarpal arthritis |
Original publication Lichtman DM, Mack GR, MacDonald RI, Gunther SF, Wilson JN. Kienböck’s disease: the role of silicone replacement arthroplasty. J Bone Joint Surg Am. 1977;59(7):899-908.
Carpal instability types
| Type | Description |
|---|---|
| DISI | Dorsi-flexion (Dorsal Intercalated Segment Instability). Most common, where lunate is rotated into dorsi-flexion (zig zag alignment of radiolunatocapitate alignment) |
| VISI | Palmar flexion (Volar Intercalated Segment Instability) |
| Ulnar translocation | Abnormal translocation of lunate ulnarward Type 1 entire carpus is translocated ulnarward Type 2 relationship between radius & scaphoid is normal but scapholunate gap is wide Rheumatoid |
| Dorsal subluxation | Malunion fracture distal radius with reversal of normal palmar tilt |
Original publication Linscheid RL, Dobyns JH, Beabout JW, Bryan RS. Traumatic instability of the wrist. Diagnosis, classification, and pathomechanics. J Bone Joint Surg Am. 1972;54(8):1612-32.
Tubiana (Dupuytren disease)
| Stage | Total flexion deformity |
|---|---|
| N | Nodule without contracture |
| 1 | 0 to 45 degrees |
| 2 | 45 to 90 degrees |
| 3 | 90 to 135 degrees |
| 4 | Over 135 degrees |
Original publication Tubiana R. Evaluation of deformities in Dupuytren’s disease. Ann Chir Main. 1986;5(1):5-11.
Ranawat (rheumatoid neurology)
| Class | Description |
|---|---|
| 1 | Pain, no neurological deficit |
| 2 | Subjective weakness, dysaesthesia and hyperreflexia |
| 3A | Objective weakness and long tract signs, ambulatory |
| 3B | Objective weakness and long tract signs, non-ambulatory |
Original publication Ranawat CS, O’Leary P, Pellicci P, Tsairis P, Marchisello P, Dorr L. Cervical spine fusion in rheumatoid arthritis. J Bone Joint Surg Am. 1979;61(7):1003-10.
mJOA (cervical myelopathy)
| Severity | mJOA score |
|---|---|
| Mild | 15 to 17 |
| Moderate | 12 to 14 |
| Severe | Under 12 |
Modic (endplate changes)
| Type | T1 | T2 | Notes |
|---|---|---|---|
| I | Decreased signal | Increased signal | Found in 4% of cases. Must be distinguished from disc space infection (in disc space infection discs have ↑ signal intensity on T2 weighted images, & in degeneration discs have ↓ T2 signal intensity) |
| II | Increased signal | Isointense or slightly ↑ | Found in 16% of cases. Represents fatty marrow conversion |
| III | Low signal | Low signal | Bony sclerosis seen on plain films |
Original publication Modic MT, Steinberg PM, Ross JS, Masaryk TJ, Carter JR. Degenerative disk disease: assessment of changes in vertebral body marrow with MR imaging. Radiology. 1988;166(1 Pt 1):193-9.
Schizas (lumbar stenosis)
| Grade | Description |
|---|---|
| A | CSF clearly visible |
| B | Rootlets fill the sac but can be individualised |
| C | No CSF, rootlets indistinguishable, posterior fat present |
| D | No CSF and no posterior epidural fat |
Disc herniation by position
| Position | Notes |
|---|---|
| Central | Can affect traversing nerve roots bilaterally, & cauda equina if large enough |
| Posterolateral | Commonest site. Herniation is to one side of PLL. Impingement of nerve root of lower vertebra |
| Foraminal | Impingement of exiting nerve root (vertebra above), 10% |
| Extraforaminal or far lateral |
Wiltse (spondylolisthesis)
| Type | Description |
|---|---|
| I | Dysplastic, congenital deficiency of L5 to S1 facets with intact pars |
| II | Isthmic, pars lesion from stress fracture or elongation |
| III to VI | Degenerative, traumatic, pathological and iatrogenic, mostly adult |
Original publication Wiltse LL, Newman PH, Macnab I. Classification of spondylolisis and spondylolisthesis. Clin Orthop Relat Res. 1976(117):23-9.
Meyerding (slip grade)
| Grade | Slip |
|---|---|
| 1 | 1 to 25% |
| 2 | 26 to 50% |
| 3 | 51 to 75% |
| 4 | 76 to 100% |
| 5 | More than 100%, spondyloptosis |
Key reference (original not indexed in PubMed) Koslosky E, Gendelberg D. Classification in Brief: The Meyerding Classification System of Spondylolisthesis. Clin Orthop Relat Res. 2020;478(5):1125-1130.
Resnick criteria (DISH)
| Criterion | |
|---|---|
| 1 | Flowing ossification along the anterolateral aspect of at least four contiguous vertebral bodies |
| 2 | Relative preservation of disc height |
| 3 | No facet ankylosis and no sacroiliac erosion, sclerosis or fusion |
Original publication Resnick D, Niwayama G. Radiographic and pathologic features of spinal involvement in diffuse idiopathic skeletal hyperostosis (DISH). Radiology. 1976;119(3):559-68.
Basilar invagination
| Type | Causes |
|---|---|
| Primary (congenital) | Associated with vertebral anomalies (atlanto-occipital fusion, hypoplasia of the atlas, Klippel-Feil) Associated with skeletal dysplasias (achondroplasia, spondyloepiphyseal dysplasia, Morquio syndrome) |
| Secondary | Skull softening disorders (severe osteoporosis, osteomalacia, rickets, Paget’s, osteogenesis imperfecta, RA, neurofibromatosis) |
Cervical rib
| Type | Description |
|---|---|
| True neurogenic | Objective neurological deficit |
| Disputed neurogenic | Symptoms and no objective findings |
| Arterial | |
| Venous |
Crowe (adult DDH)
| Type | Subluxation |
|---|---|
| I | Under 50% |
| II | 50 to 75% |
| III | 75 to 100% |
| IV | Over 100% |
Original publication Crowe JF, Mani VJ, Ranawat CS. Total hip replacement in congenital dislocation and dysplasia of the hip. J Bone Joint Surg Am. 1979;61(1):15-23.
Hartofilakidis (adult DDH)
| Type | Description |
|---|---|
| A | Head within the true acetabulum |
| B | Low dislocation, false acetabulum overlapping the true |
| C | High dislocation, no contact with the true acetabulum |
Femoroacetabular impingement
| Type | Description |
|---|---|
| Cam | Aspherical anterosuperior head neck junction, young male athletes, after SCFE or Perthes disease |
| Pincer | Global (coxa profunda, protrusio) or focal (retroversion) overcoverage, more common in women |
| Mixed | The most common pattern |
Original publication Ganz R, Parvizi J, Beck M, Leunig M, Nötzli H, Siebenrock KA. Femoroacetabular impingement: a cause for osteoarthritis of the hip. Clin Orthop Relat Res. 2003(417):112-20.
Hip-spine classification
| Group | Sagittal alignment | Spine mobility |
|---|---|---|
| 1A | Normal alignment, PI − LL ≤10° | Normal mobility |
| 1B | Normal alignment, PI − LL ≤10° | Stiff spine |
| 2A | Flatback deformity, PI − LL >10° | Normal mobility |
| 2B | Flatback deformity, PI − LL >10° | Stiff spine. Highest risk, malaligned spine that cannot compensate |
Ficat and Arlet (femoral head AVN)
| Stage | Clinical | Imaging |
|---|---|---|
| 0 | Preclinical | Radiographs normal, bone scan cold, MRI double line on T2 |
| I | Onset of ischaemia | Radiographs normal, changes on MRI or bone scan only |
| II | Pain | Early cystic and sclerotic change with a preserved head contour |
| III | Structural change | Crescent sign and flattening of the head |
| IV | Degenerative change | Joint space narrowing and secondary osteoarthritis |
Original publication Ficat RP. Idiopathic bone necrosis of the femoral head. Early diagnosis and treatment. J Bone Joint Surg Br. 1985;67(1):3-9.
ARCO (femoral head AVN)
| Stage | Description |
|---|---|
| 0 | Bone biopsy = AVN All other Ix normal |
| 1 | Normal X-ray MRI +ve |
| 2 | Typical X-ray changes no collapse |
| 3 | Collapse For stage 3 collapse on XR subdivided A = 2mm or < 15% B = 2-4mm or 15-30% C = > 4mm or > 30% |
| 4 | Osteoarthritis |
Kellgren and Lawrence (osteoarthritis)
| Grade | Description |
|---|---|
| 0 | None |
| 1 | Doubtful |
| 2 | Minimal |
| 3 | Moderate |
| 4 | Severe |
Original publication Kellgren JH, Lawrence JS. Radiological assessment of osteo-arthrosis. Ann Rheum Dis. 1957;16(4):494-502.
Brooker (heterotopic ossification)
| Grade | Description |
|---|---|
| 1 | Isolated islands of bone |
| 2 | Bone spurs from femur / ilium, >1cm gap |
| 3 | Bone spurs, <1cm gap |
| 4 | Bone spurs with apparent bony ankylosis |
Original publication Brooker AF, Bowerman JW, Robinson RA, Riley Lh Jr. Ectopic ossification following total hip replacement. Incidence and a method of classification. J Bone Joint Surg Am. 1973;55(8):1629-32.
Noyes (varus knee)
| Type | Description |
|---|---|
| Primary varus | Osseous tibiofemoral varus |
| Double varus | Adds lateral tibiofemoral separation from lateral laxity |
| Triple varus | Adds varus recurvatum from posterolateral and posterior capsular insufficiency |
Original publication Noyes FR, Barber-Westin SD, Hewett TE. High tibial osteotomy and ligament reconstruction for varus angulated anterior cruciate ligament-deficient knees. Am J Sports Med. 2000;28(3):282-96.
Watanabe (discoid meniscus)
| Type | Description | Treatment of symptomatic tears |
|---|---|---|
| 1 Complete (stable), most common | Discoid meniscus covers tibial plateau. Lateral ligaments are intact, therefore stable | Saucerization to stable peripheral rim of 6-8 mm |
| 2 Incomplete | Similar to complete, covers less of the plateau | Saucerization to stable peripheral rim of 6-8 mm |
| 3 Wrisberg ligament type (unstable) | Deficiency of posterior horn meniscal tibial ligaments. Unstable and hypermobile posterior horn. On knee extension, abnormal meniscus is pulled posteromedially into the intercondylar notch (instead of gliding forward) due to the action of the meniscofemoral ligaments. Probably responsible for the true “snapping knee” | Try to repair to reattach the posterior horn. Meniscectomy may be needed since it lacks posterior meniscal tibial attachments & has unstable posterior horn. Meniscal transplant not yet shown to be effective in skeletally immature patients |
Plica
| Type | Features |
|---|---|
| Suprapatellar | Five types (midline, medial, lateral, incomplete, complete). Complete type seals off pouch completely |
| Medial patellar | Least common. Originates from medial wall of knee joint and runs obliquely down to insert in medial infrapatellar fat pad. Most likely to be symptomatic, gets caught between patella & femur |
| Infrapatellar (ligamentum mucosum) | From notch to fat pad. Most common. Always asymptomatic |
Outerbridge (cartilage)
| Grade | Description |
|---|---|
| I | Softening |
| II | Fissuring under 1.3 cm |
| III | Fissuring over 1.3 cm |
| IV | Erosion to subchondral bone |
Original publication Outerbridge RE. The etiology of chondromalacia patellae. J Bone Joint Surg Br. 1961;43-B:752-7.
ICRS (cartilage)
| Grade | Description |
|---|---|
| 1 | Superficial |
| 2 | Under half depth |
| 3 | Over half depth |
| 4 | Through subchondral bone |
Original publication Brittberg M, Winalski CS. Evaluation of cartilage injuries and repair. J Bone Joint Surg Am. 2003;85-A Suppl 2:58-69.
SONK staging
| Stage | Description | |
|---|---|---|
| 1 | incipient stage | ~ Severe pain ~ X-ray normal or some focal osteoporosis ~ Bone scan & MRI positive |
| 2 | avascular stage | ~ Pain ~ X-ray: radiolucent oval shadow on the medial femoral condyle with some flattening of the articular surface. ~ Bone scan & MRI positive |
| 3 | collapsed stage | ~ Pain ~ X-ray: collapse of the subchondral bone plate with a calcified plate & clear sclerotic halo |
| 4 | degenerative stage | ~ Severe pain with or without deformity ~ X-ray: shallow concave articular surface with secondary OA changes, a narrowed joint space & varus deformity. |
Berndt and Harty (talar OCD)
| Stage | Description |
|---|---|
| 1 | Compression |
| 2 | Partially detached |
| 3 | Detached in its bed |
| 4 | Displaced |
| 5 (Loomer) | Subchondral cyst |
Original publication Berndt AL, Harty M. Transchondral fractures (osteochondritis dissecans) of the talus. J Bone Joint Surg Am. 1959;41-A:988-1020.
Hepple (talar OCD on MRI)
| Stage | Description |
|---|---|
| 1 | Cartilage damage only |
| 2a | Underlying fracture with oedema |
| 2b | Underlying fracture without oedema |
| 3 | Detached, undisplaced |
| 4 | Displaced |
| 5 | Subchondral cyst |
Original publication Hepple S, Winson IG, Glew D. Osteochondral lesions of the talus: a revised classification. Foot Ankle Int. 1999;20(12):789-93.
Coughlin and Shurnas (hallux rigidus)
| Grade | Dorsiflexion | Radiographs | Clinical |
|---|---|---|---|
| 0 | 40 to 60° (10 to 20% loss) | Normal | Stiffness only |
| 1 | 30 to 40° (20 to 50% loss) | Dorsal osteophyte, minimal joint narrowing | Mild or occasional pain and stiffness at extremes of motion |
| 2 | 10 to 30° (50 to 75% loss) | Mild to moderate narrowing, osteophytes, under a quarter of the dorsal head involved | Moderate to severe, more constant pain and stiffness |
| 3 | Under 10° (75 to 100% loss) | Severe narrowing, cysts, over a quarter of the dorsal head involved | Near constant pain, no pain in mid range |
| 4 | As grade 3 | As grade 3 | Pain in mid range of passive motion |
Original publication Coughlin MJ, Shurnas PS. Hallux rigidus. Grading and long-term results of operative treatment. J Bone Joint Surg Am. 2003;85(11):2072-88.
Tibialis posterior dysfunction
| Stage | Features | Management |
|---|---|---|
| I | Tenosynovitis, no deformity | Orthosis, immobilisation, tenosynovectomy |
| II | Flexible flatfoot | FDL transfer and medialising calcaneal osteotomy, with or without lateral column lengthening and spring ligament repair |
| III | Fixed hindfoot valgus | Triple arthrodesis |
| IV | Valgus tilt of the talus from deltoid failure | Triple or tibiotalocalcaneal arthrodesis, with deltoid reconstruction if the ankle is flexible |
Eichenholtz (Charcot foot)
| Stage | Phase | Description |
|---|---|---|
| 0 | Early | Joint oedema present, bone-scan positive, normal radiographs |
| 1 | Fragmentation | Maximal oedema, osseous fragmentation and joint dislocation |
| 2 | Coalescence | Oedema reducing, fragment coalescence and resorption of fine bone debris |
| 3 | Reconstruction | Oedema resolved, radiographic evidence of remodelling and consolidation of bone fragments |
Key reference (original not indexed in PubMed) Rosenbaum AJ, DiPreta JA. Classifications in brief: Eichenholtz classification of Charcot arthropathy. Clin Orthop Relat Res. 2015;473(3):1168-71.
Smillie (Freiberg disease)
| Stage | Features |
|---|---|
| I | Subchondral fissure fracture through the ischaemic epiphysis |
| II | Central bone resorption with early collapse of the articular surface |
| III | Further collapse with a central projection, plantar cartilage intact |
| IV | Fracture of the projection with loose body formation |
| V | Flattening and deformity of the head with arthrosis |
Coughlin (tailor bunionette)
| Type | Description |
|---|---|
| 1 | Enlarged fifth metatarsal head or lateral condyle |
| 2 | Lateral bowing of the fifth metatarsal shaft with a normal intermetatarsal angle |
| 3 | Increased fourth to fifth intermetatarsal angle, the most common |
Original publication Coughlin MJ. Treatment of bunionette deformity with longitudinal diaphyseal osteotomy with distal soft tissue repair. Foot Ankle. 1991;11(4):195-203.
Enneking (benign tumours)
| Stage | Behaviour | Examples |
|---|---|---|
| 1 Latent | Grows, then stops, with a tendency to spontaneous resolution | Non ossifying fibroma, lipoma |
| 2 Active | Progressive growth, excision leaves tumour in the reactive zone | Aneurysmal bone cyst |
| 3 Aggressive | Locally aggressive, extends through the capsule into the reactive zone, does not metastasise | Giant cell tumour, desmoid |
Enneking (malignant tumours)
| Stage | Grade | Site |
|---|---|---|
| IA | Low | Intracompartmental |
| IB | Low | Extracompartmental |
| IIA | High | Intracompartmental |
| IIB | High | Extracompartmental |
| III | Any grade with metastasis | Any |
Original publication Enneking WF, Spanier SS, Goodman MA. A system for the surgical staging of musculoskeletal sarcoma. Clin Orthop Relat Res. 1980;(153):106-20.
Enneking surgical margins
| Margin | Description |
|---|---|
| Intralesional | Plane through tumour, as in curettage |
| Marginal | Through the reactive zone, which may hold satellite cells |
| Wide | Tumour with reactive zone and normal cuff, skip lesions possible |
| Radical | Entire compartment removed |
Original publication Enneking WF, Spanier SS, Goodman MA. A system for the surgical staging of musculoskeletal sarcoma. Clin Orthop Relat Res. 1980(153):106-20.
| Variable | 1 | 2 | 3 |
|---|---|---|---|
| Site | Upper limb | Lower limb | Peritrochanteric |
| Pain | Mild | Moderate | Functional |
| Lesion | Blastic | Mixed | Lytic |
| Size | Under one third | One third to two thirds | Over two thirds |
Original publication Mirels H. Metastatic disease in long bones. A proposed scoring system for diagnosing impending pathologic fractures. Clin Orthop Relat Res. 1989(249):256-64.
SINS (spinal instability)
| Score | Category |
|---|---|
| 0 to 6 | Stable |
| 7 to 12 | Potentially unstable |
| 13 to 18 | Unstable |
Lodwick (lytic patterns)
| Grade | Description |
|---|---|
| IA | Geographic with sclerotic rim |
| IB | Geographic, well defined, no sclerotic rim |
| IC | Geographic with ill defined margin |
| II | Moth-eaten |
| III | Permeative |
Original publication Lodwick GS, Wilson AJ, Farrell C, Virtama P, Dittrich F. Determining growth rates of focal lesions of bone from radiographs. Radiology. 1980;134(3):577-83.
Campanacci (giant cell tumour)
| Grade | Description |
|---|---|
| 1 | Intramedullary lesion confined to bone |
| 2 | Thinned, expanded cortex |
| 3 | Cortical breakout |
Aneurysmal bone cyst
| Type | Description |
|---|---|
| Primary | Arise de novo |
| Secondary | Arise in pre-existing tumours, frequently GCTs. More than 50% of ABCs arise from preexisting lesions |
Simple bone cyst
| Type | Description |
|---|---|
| A: Active | usually juxta-epiphyseal |
| B: Inactive | cyst lies nearer the diaphysis (is more than 2cm removed from the physis) Inactive cysts are less aggressive & more amenable to treatment |
Osteosarcoma by anatomy
| Type | Subtypes |
|---|---|
| 1. Central | Further subclassified by grade (high grade, 10-20yo, most common, or low grade) and pathology (conventional, telangiectatic, small cell, giant cell) |
| 2. Juxtacortical (surface osteosarcoma) | Low grade (30-40yo, usually low grade) or high grade Parosteal or Periosteal |
| 3. Intra-cortical | |
| 4. Soft tissue | |
| 5. Secondary |
Chondrosarcoma types
| Type | Description |
|---|---|
| Primary | Arise de novo, most |
| Secondary, from pre-existing cartilage lesions | Osteocartilaginous exostosis Enchondroma (Ollier disease, Maffucci syndrome) Periosteal chondroma Chondroblastoma Chondromyxofibroma Synovial chondromatosis Earlier age of presentation than the primary tumours |
| Secondary, from other cause | Pagets Radiation Later presentation than the primary tumours |
Lipomatous tumours
| Tumour | Features |
|---|---|
| Lipoma | Most common soft tissue tumour, superficial, soft and mobile |
| Intramuscular lipoma | Deep, may infiltrate muscle |
| Atypical lipomatous tumour | Deep and large, MDM2 amplification, local recurrence without metastasis |
| Myxoid liposarcoma | Metastasises to unusual sites such as spine and retroperitoneum. Whole spine MRI for staging |
| Dedifferentiated and pleomorphic liposarcoma | High grade, metastatic potential |
Cierny-Mader (osteomyelitis anatomy)
| Anatomic type | Description |
|---|---|
| I | Medullary, endosteal disease confined to the medullary canal |
| II | Superficial, contiguous infection of the outer cortex beneath a soft tissue defect |
| III | Localised, full thickness cortical sequestration that can be excised without loss of stability |
| IV | Diffuse, permeative disease with mechanical instability before or after debridement |
Cierny-Mader (host)
| Host | Description |
|---|---|
| A | Healthy host with normal physiological, metabolic and immune function (for example WCC over 1,500/mm3, albumin over 3.5 g/dL, protein over 6 g/dL, ferritin 10 to 200 ng/mL, transferrin under 200 mg/dL) |
| B | Local or systemic compromise, or both |
| C | Severe compromise, treatment worse than the disease, not a surgical candidate |
Original publication Cierny G 3rd, Mader JT, Penninck JJ. A clinical staging system for adult osteomyelitis. Clin Orthop Relat Res. 2003;(414):7-24.
Tsukayama (periprosthetic infection)
| Type | Description |
|---|---|
| Early postoperative | Within about four weeks |
| Acute haematogenous | Sudden onset in a well functioning joint |
| Chronic | Insidious onset beyond four weeks |
| Positive intraoperative cultures | Positive cultures at presumed aseptic revision |
Original publication Tsukayama DT, Estrada R, Gustilo RB. Infection after total hip arthroplasty. A study of the treatment of one hundred and six infections. J Bone Joint Surg Am. 1996;78(4):512-23.
CRPS stages
| Stage 1 | Stage 2 | Stage 3 | |
|---|---|---|---|
| Acute | Dystrophic | Atrophic | |
| Time | 0-3/12 | 3-6/12 | > 6/12 |
| Symptoms | Continued localised pain Aggravated by stress | Proximal spread of pain | Intractable pain |
| Signs | Skin changes Swollen & warm sensory – allodynia autonomic – wet with excess swelling motor – joints have decreased ROM | Skin changes Cool & dry Mottled & dusky Atrophic with shininess & decreased hair Oedema of limb | Atrophy of skin, muscles & bone Flexion contractures |
| Investigations | XR: normal Bone scan +ve with Periarticular accentuation on delayed scan Highly specific Not predictive | XR: Early osteoporosis | XR: Narrow joint space Diffuse osteoporosis |
Cook and Purdam (tendinopathy)
| Stage | Description |
|---|---|
| Reactive | Thickened tendon with intact collagen, reversible with load reduction |
| Disrepair | Matrix breakdown and early neovascularity |
| Degenerative | Cell death and disordered matrix, prone to rupture |
Original publication Cook JL, Purdam CR. Is tendon pathology a continuum? A pathology model to explain the clinical presentation of load-induced tendinopathy. Br J Sports Med. 2009;43(6):409-16.
ACR 1987 (rheumatoid arthritis)
| Criterion | Requirement |
|---|---|
| Morning stiffness | > 1 hour |
| Symmetrical arthritis | > 6/52 |
| Arthritis affecting 3 joints or more | > 6/52 |
| Arthritis of hand | > 6/52 |
| Rheumatoid nodules | Present |
| Rheumatoid factor | Positive |
| Radiological changes | Present |
Ankylosing spondylitis criteria
| Requirement | Criteria |
|---|---|
| Required | Positive XR sacroiliitis |
| Plus one or more | History of lumbar spine pain Stiff lumbar spine Chest expansion < 1″ at 4th intercostal space |
CPPD
| Type | Notes |
|---|---|
| Idiopathic chondrocalcinosis | By far the most common. Pseudorheumatoid arthritis with continuous attack, pseudo osteoarthritis with acute attacks, pseudo osteoarthritis without acute attacks, lanthanic (asymptomatic) |
| Hereditary | |
| Secondary (“WHIP A DOG”) | Wilson’s, haemochromatosis, hyperparathyroidism, hypothyroidism, hypophosphatasia, idiopathic, pseudogout, pernicious anaemia, acromegaly, diabetes, degenerate, ochronosis (alkaptonuria), gout |
Haemophilia severity
| Factor level | Bleeding risk |
|---|---|
| > 50% | Normal |
| 25-50% | Seldom a problem |
| 5-25% | Severe bleed with surgery (mild) |
| 1-5% | Severe bleed with minor injury (moderate) |
| < 1% | Spontaneous bleed (severe) |
Haemophilic arthropathy (radiological)
| Stage | Description |
|---|---|
| 1 | Acute haemarthrosis Soft tissue swelling |
| 2 | Subacute haemarthrosis Epiphyseal osteoporosis Epiphyseal overgrowth |
| 3 | No significant narrowing of joint Squaring of patella Enlarged femoral condyles Widened intercondylar notch in knee Widened trochlear notch at elbow |
| 4 | Marked narrowing of joint space |
| 5 | Joint destruction Mimics RA / TB |
Ehlers-Danlos 2017
| Type | Features |
|---|---|
| Hypermobile | Most common, no identified gene |
| Classical | COL5A1 or COL5A2 mutations |
| Vascular | COL3A1 mutations |
| Kyphoscoliotic | PLOD1 or FKBP14 mutations |
Neurofibromatosis
| Type | Features |
|---|---|
| NF 1 | 2 or more of the National Institute of Health criteria At least 6 café au lait spots (> 5mm in children, > 15 mm in adults) 2 neurofibromas or 1 plexiform neurofibroma Freckling of the inguinal or axillary region Optical glioma At least 2 Lisch nodules (iris condensations / hamartoma of the iris) A first degree relative with NF A distinctive osseous lesion (sphenoid dysplasia, thinning of long bone cortex with or without pseudarthrosis) |
| NF 2 | Bilateral acoustic neuromas (bilateral vestibular schwannomas). Paucity of peripheral findings |
Wynne-Davies (ligamentous laxity)
| Joint | Laxity |
|---|---|
| Thumb | Touching forearm on flexing wrist |
| Fingers | Parallel to forearm with wrist extension |
| Elbows | Extend past 180° |
| Knees | Extend past 180° |
| Foot | Dorsiflex past 45° |
Muscular dystrophy
| Inheritance | Types |
|---|---|
| X linked | Duchenne, Becker, Emery-Dreifuss |
| Autosomal recessive | Limb girdle, infantile facioscapulohumeral |
| Autosomal dominant | Facioscapulohumeral, distal, ocular, oculopharyngeal |
Seddon (nerve injury)
| Type | Pathology | Recovery |
|---|---|---|
| Neurapraxia | Local conduction block from segmental demyelination, axon intact, no Wallerian degeneration | Full |
| Axonotmesis | Axon and myelin disrupted with the connective tissue framework preserved, Wallerian degeneration follows | By regeneration |
| Neurotmesis | Complete disruption | None without surgery |
Sunderland (nerve injury)
| Grade | Injury | Recovery |
|---|---|---|
| I | Neurapraxia, conduction block | Full |
| II | Axon disrupted, endoneurium intact | Full, at the rate of regeneration |
| III | Endoneurium disrupted, perineurium intact | Incomplete, from axonal misdirection |
| IV | Only epineurium intact | Neuroma in continuity needing resection and repair or grafting |
| V | Complete transection | None without repair |
| VI (Mackinnon) | Mixed injury with different grades in different fascicles | Variable |
Original publication Sunderland S. A classification of peripheral nerve injuries producing loss of function. Brain. 1951;74(4):491-516.
Use the up and down arrow keys to move through the classifications. In Test me mode, press space to show the answer.
Condition pages
Each link opens the condition page, where the classification sits in a table with its original reference.
| Region | Classification | Page |
|---|---|---|
| Shoulder | Neer impingement stages and cuff tear groups | Rotator Cuff Tears |
| Shoulder | Snyder SLAP types | SLAP Lesions |
| Shoulder | Stanmore polar types | Multidirectional Instability of the Shoulder |
| Shoulder | ACJ arthritis patterns | Acromioclavicular (ACJ) Arthritis |
| Elbow | Mayo rheumatoid elbow | Elbow Arthritis |
| Elbow | Minami capitellar OCD | Capitellar Osteochondritis Dissecans |
| Wrist and hand | Lichtman Kienböck stages | Kienbock’s Disease |
| Wrist and hand | SLAC and SNAC | Four-corner Fusion vs Proximal Row Carpectomy |
| Wrist and hand | Tubiana Dupuytren stages | Dupuytren’s Disease |
| Hip | Crowe and Hartofilakidis | Congenital Hip Disease |
| Hip | Hip-spine classification | Hip-Spine Relationship in THR |
| Knee | Outerbridge and ICRS cartilage grades | Articular Cartilage Defects of the Knee |
| Knee | Watanabe discoid meniscus | Discoid Meniscus |
| Knee | Noyes varus knee | Osteotomies for Knee Instability |
| Knee | Hughston and Fanelli posterolateral | Posterolateral Instability of the Knee |
| Foot and ankle | Berndt and Harty, Hepple talar OCL | Osteochondral Lesions of the Talus |
| Cervical spine | Ranawat neurological classification | Rheumatoid Arthritis |
| Cervical spine | mJOA myelopathy severity | Cervical Spondylosis |
| Cervical spine | Cheng torticollis groups | Congenital Muscular Torticollis |
| Thoracolumbar spine | Schizas stenosis grades | Lumbar Canal Stenosis |
| Thoracolumbar spine | Resnick criteria for DISH | Diffuse Idiopathic Skeletal Hyperostosis (DISH) |
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.