Radiographic systems to classify osteoarthritis vary by which joint is being investigated. In osteoarthritis, the choice of treatment is based on pain and decreased function, but radiography can be useful before surgery in order to prepare for the procedure.
Vertebral column
There are many grading systems for degeneration of intervertebral discs and facet joints in the cervical and lumbar vertebrae, of which the following radiographic systems can be recommended in terms of interobserver reliability:[1]
Kellgren grading of cervical disc degeneration
Kellgren grading of cervical facet joint degeneration
Lane grading of lumbar disc degeneration
Thompson grading of lumbar disc degeneration (by magnetic resonance imaging)
Pathria grading of lumbar facet joint degeneration (by computed tomography)
Weishaupt grading of lumbar facet joint degeneration (by MRI and computed tomography)
Kellgren grading of cervical disc degeneration[2]
I
Minimal anterior osteophytosis
II
Definite anterior osteophytosis
Possible disc space narrowing
Some endplate sclerosis
III
Moderate disc space narrowing
Definite endplate sclerosis
Osteophytosis
IV
Severe disc space narrowing
Endplate sclerosis
Multiple large osteophytes.
Lane grading of lumbar disc degeneration[1]
Grade
Joint space narrowing
Osteophytes
Sclerosis
0
None
None
None
1
Definite but mild narrowing
Small
Present
2
Moderate
Moderate
–
3
Severe (complete joint space loss)
Large
–
The Thomson grading system is regarded to have more academic than clinical value.[1]
Thomson grading of lumbar disc degeneration[1]
Grade
Nucleus
Anulus
Endplate
Vertebral body
I
Bulging gel
Discrete fibrous laminae
Hyaline, uniform thickness
Rounded margins
II
Peripheral white fibrous tissue
Mucinous material between laminae
Irregular thickness
Pointed margins
III
Consolidated fibrous tissue
Extensive mucinous infiltration; loss of annular-nuclear demarcation
Focal defects in cartilage
Small chondrophytes or osteophytes at margins
IV
Horizontal clefts parallel to endplate
Focal disruptions
Fibrocartilage extending from subchondral bone; irregularity and focal sclerosis in subchondral bone
Osteophytes smaller than 2 mm
V
Clefts extended through nucleus and annulus
Diffuse sclerosis
Osteophytes greater than 2 mm
Shoulder
The Samilson–Prieto classification is preferable for osteoarthritis of the glenohumeral joint.[3]
Samilson–Prieto classification[4]
Grade
Description
Mild
Exostosis of inferior humerus and/or glenoid measuring less than 3 mm
Moderate
Exostosis of inferior humerus and/or glenoid measuring 3–7 mm, and slight irregularity of the joint
Severe
Exostosis of inferior humerus and/or glenoid measuring more than 7 mm in height as well as sclerosis and narrowing of the joint space (normal joint space is 4–5 mm).[5]
Hip
The most commonly used radiographic classification system for osteoarthritis of the hip joint is the Kellgren–Lawrence system (or KL system).[6] It uses plain radiographs.
Osteoarthritis of the hip joint may also be graded by Tönnis classification. There is no consensus whether it is more or less reliable than the Kellgren-Lawrence system.[8]
severe joint space narrowing, or joint space obliteration
severe deformity of the head
Knee
For the grading of osteoarthritis in the knee, the International Knee Documentation Committee (IKDC) system is regarded to have the most favorable combination of interobserver precision and correlation to knee arthroscopy findings.[10] It was formed by a group of knee surgeons from Europe and America who met in 1987 to develop a standard form to measure results of knee ligament reconstructions.[11]
The Ahlbäck system has been found to have comparable interobserver precision and arthroscopy correlation to the IKDC system, but most of the span of the Ahlbäck system focused at various degrees of bone defect or loss, and it is therefore less useful in early osteoarthritis.[10] Systems that have been found to have lower interobserver precision and/or arthroscopy correlation are those developed by Kellgren and Lawrence, Fairbank, Brandt, and Jäger and Wirth.[10]
International Knee Documentation Committee (IKDC) system[10]
Grade
Findings
A
No joint space narrowing, defined in this system as at least 4 mm joint space
B
At least 4 mm joint space, but small osteophytes, slight sclerosis, or femoral condyle flattening
C
2–4 mm joint space
D
< 2 mm joint space
Ahlbäck classification[12]
Grade
Findings
I
Joint space narrowing, with or without subchondral sclerosis. Joint space narrowing is defined by this system as a joint space less than 3 mm, or less than half of the space in the other compartment, or less than half of the space of the homologous compartment of the other knee.
II
Obliteration of the joint space
III
Bone defect/loss < 5 mm
IV
Bone defect/loss between 5 and 10 mm
V
Bone defect/loss > 10 mm, often with subluxation and arthritis of the other compartment
For the patellofemoral joint, a classification by Merchant 1974 uses a 45° "skyline" view of the patella:[13]
Merchant system
Stage
Description
1 (mild)
Patellofemoral joint space > 3 mm
2 (moderate)
Joint space < 3 mm but no bony contact
3 (severe)
Bony surfaces in contact over less than one quarter of the joint surface
4 (very severe)
Bony contact throughout the entire joint surface
Other joints
In the temporomandibular joint, subchondral sclerosis of the mandibular condyle has been described as an early change, condylar flattening as a feature of progressive osteoarthritis, and narrowing of the temporomandibular joint space as a late stage change.[14] A joint space of between 1.5 and 4 mm is regarded as normal.[15]
For the ankle, the Kellgren–Lawrence scale, as described for the hip, has been recommended.[16] The distances between the bones in the ankle are normally as follows:[17]
Talus - medial malleolus: 1.70 ± 0.13 mm
Talus - tibial plafond: 2.04 ± 0.29 mm
Talus - lateral malleolus: 2.13 ± 0.20 mm
See also
WOMAC, a non-radiographic classification system of osteoarthritis, taking into account pain, stiffness and functional limitation.[18]
References
^ abcdKettler, Annette; Wilke, Hans-Joachim (2005). "Review of existing grading systems for cervical or lumbar disc and facet joint degeneration". European Spine Journal. 15 (6): 705–718. doi:10.1007/s00586-005-0954-y. ISSN 0940-6719. PMC 3489462. PMID 16172902.
^Ofiram, Elisha; Garvey, Timothy A.; Schwender, James D.; Denis, Francis; Perra, Joseph H.; Transfeldt, Ensor E.; Winter, Robert B.; Wroblewski, Jill M. (2009). "Cervical degenerative index: a new quantitative radiographic scoring system for cervical spondylosis with interobserver and intraobserver reliability testing". Journal of Orthopaedics and Traumatology. 10 (1): 21–26. doi:10.1007/s10195-008-0041-3. ISSN 1590-9921. PMC 2657349. PMID 19384631.
^Brox, Jens; Lereim, Paul; Merckoll, Else; Finnanger, Anne Marie (2009). "Radiographic classification of glenohumeral arthrosis". Acta Orthopaedica Scandinavica. 74 (2): 186–189. doi:10.1080/00016470310013932. ISSN 0001-6470. PMID 12807327. S2CID 36730645.
^Page 117 in Barbara N. W. Weissman (2009). Imaging of Arthritis and Metabolic Bone Disease. Elsevier Health Sciences. ISBN 9780323041775.
^"Glenohumeral joint space". radref.org., in turn citing: Petersson, Claes J.; Redlund-Johnell, Inga (2009). "Joint Space in Normal Gleno-Humeral Radiographs". Acta Orthopaedica Scandinavica. 54 (2): 274–276. doi:10.3109/17453678308996569. ISSN 0001-6470. PMID 6846006.
^Zdravko Jotanovic, Radovan Mihelic, Gordan Gulan, Branko Sestan, Zlatko Dembic (2015). "Osteoarthritis of the hip: An overview". Periodicum Biologorum. 117 (1).{{cite journal}}: CS1 maint: multiple names: authors list (link)
^ abLequesne, M (2004). "The normal hip joint space: variations in width, shape, and architecture on 223 pelvic radiographs". Annals of the Rheumatic Diseases. 63 (9): 1145–1151. doi:10.1136/ard.2003.018424. ISSN 0003-4967. PMC 1755132. PMID 15308525.
^Terjesen, Terje; Gunderson, Ragnhild B (2012). "Radiographic evaluation of osteoarthritis of the hip". Acta Orthopaedica. 83 (2): 185–189. doi:10.3109/17453674.2012.665331. ISSN 1745-3674. PMC 3339535. PMID 22329668.
^"Tönnis Classification of Osteoarthritis by Radiographic Changes". Society of Preventive Hip Surgery. Retrieved 2016-12-13.
^ abcdWright, RW (2014). "Osteoarthritis Classification Scales: Interobserver Reliability and Arthroscopic Correlation". The Journal of Bone and Joint Surgery. American Volume. 96 (14): 1145–1151. doi:10.2106/JBJS.M.00929. ISSN 0021-9355. PMC 4083772. PMID 25031368.
^Hefti F, Müller W, Jakob RP, Stäubli HU (1993). "Evaluation of knee ligament injuries with the IKDC form". Knee Surg Sports Traumatol Arthrosc. 1 (3–4): 226–34. doi:10.1007/bf01560215. PMID 8536037. S2CID 22344987.
^Hernández-Vaquero, Daniel; Fernández-Carreira, José Manuel (2012). "Relationship between radiological grading and clinical status in knee osteoarthritis. a multicentric study". BMC Musculoskeletal Disorders. 13 (1): 194. doi:10.1186/1471-2474-13-194. ISSN 1471-2474. PMC 3520822. PMID 23046837.
^Page 722 in Gary S. Firestein, Ralph Budd, Sherine E Gabriel, Iain B. McInnes, James R O'Dell (2012). Kelley's Textbook of Rheumatology E-Book. Elsevier Health Sciences. ISBN 9781455737673.{{cite book}}: CS1 maint: multiple names: authors list (link)
^Massilla Mani, F.; Sivasubramanian, S. Satha (2016). "A study of temporomandibular joint osteoarthritis using computed tomographic imaging". Biomedical Journal. 39 (3): 201–206. doi:10.1016/j.bj.2016.06.003. ISSN 2319-4170. PMC 6138784. PMID 27621122.
^Nicolas Holzer, Davide Salvo, Anne Karien Marijnissen, Aminudin Che Ahmad, Emanuele Sera, Pierre Hoffmeyer, Anne Lübbeke Wolff, Mathieu Assal (2017-09-14). "How to assess ankle osteoarthritis: comparison of the Kellgren and Lawrence scale with functional outcome and digital image analysis". Orthopaedic Proceedings. 94-B.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^Imai, Kan; Ikoma, Kazuya; Kido, Masamitsu; Maki, Masahiro; Fujiwara, Hiroyoshi; Arai, Yuji; Oda, Ryo; Tokunaga, Daisaku; Inoue, Nozomu; Kubo, Toshikazu (2015). "Joint space width of the tibiotalar joint in the healthy foot". Journal of Foot and Ankle Research. 8 (1): 26. doi:10.1186/s13047-015-0086-5. ISSN 1757-1146. PMC 4490633. PMID 26146520.
^Quintana, José M.; Escobar, Antonio; Arostegui, Inmaculada; Bilbao, Amaia; Azkarate, Jesús; Goenaga, J. Ignacio; Arenaza, Juan C. (2006). "Health-Related Quality of Life and Appropriateness of Knee or Hip Joint Replacement". Archives of Internal Medicine. 166 (2): 220–6. doi:10.1001/archinte.166.2.220. ISSN 0003-9926. PMID 16432092.