The one-leg standing radiograph: An improved technique to evaluate the severity of knee osteoarthritis.
OBJECTIVE
The purpose of this study was to compare the joint space width between one-leg and both-legs standing radiographs in order to diagnose a primary osteoarthritis of the knee.


METHODS
Digital radiographs of 100 medial osteoarthritic knees in 50 patients were performed. The patients had undergone one-leg standing anteroposterior (AP) views by standing on the affected leg while a both-legs standing AP view was undertaken while standing on both legs. The severity of the osteoarthritis was evaluated using the joint space width and Kellgren-Lawrence (KL) radiographic classification. The t-test was used for statistical analysis.


RESULTS
The mean medial joint space width found in the one-leg and in the both-legs standing view were measured at 1.8 mm and 2.4 mm, respectively (p < 0.001, 95% CI 0.5 to 0.7). 33%, 47.4% and 23.1% of the knees diagnosed with a KL grade of I, II and III in the both-legs standing views were changed to KL grade II, III and IV in the one-leg standing views, respectively. No changes for KL IV osteoarthritis diagnoses have been found between both- and one-leg standing views.


CONCLUSIONS
One-leg standing radiographs better represent joint space width than both-legs standing radiographs. 32% of both-legs standing radiographs have changed the KL grading to a more severe grade than that in the one-leg standing radiographs.Cite this article: P. Pinsornsak, K. Naratrikun, S. Kanitnate, T. Sangkomkamhang. The one-leg standing radiograph: An improved technique to evaluate the severity of knee osteoarthritis. Bone Joint Res 2016;5:436-441. DOI: 10.1302/2046-3758.59.BJR-2016-0049.R1.
Department of Orthopaedics, Thammasat University, Pathum Thani, Thailand pinpiya2003@yahoo.com.
P
P
Pinsornsak
Department of Orthopaedics, Thammasat University, Pathum Thani, Thailand.
K
K
Naratrikun
Department of Orthopaedics, Thammasat University, Pathum Thani, Thailand.
S
S
Kanitnate
Khonkaen Hospital, Khonkaen, Thailand.
T
T
Sangkomkamhang
Knee osteoarthritis; One-leg standing; Radiography
Ann Rheum Dis. 1957 Dec;16(4):494-502
13498604
J Rheumatol. 1996 Oct;23 (10 ):1756-64
8895154
Arthritis Res Ther. 2011;13(6):247
22136179
Knee Surg Sports Traumatol Arthrosc. 2010 Oct;18(10 ):1356-9
20532478
J Arthroplasty. 1995 Dec;10 (6):790-2
8749762
J Rheumatol. 1999 Dec;26(12 ):2664-74
10606380
Arthritis Rheum. 1986 Aug;29(8):1039-49
3741515
J Bone Joint Surg Am. 1988 Dec;70(10 ):1479-83
3198672
J Bone Joint Surg Br. 1999 Jul;81(4):632-5
10463735
J Bone Joint Surg Br. 1990 Jul;72 (4):639-40
2380220
Osteoarthritis Cartilage. 1998 Jul;6(4):252-9
9876394
Osteoarthritis Cartilage. 2011 May;19(5):550-6
21396469
Arthritis Rheum. 2003 Feb;48(2):378-84
12571846
Radiology. 1970 Nov;97(2):265-8
5481130
Skeletal Radiol. 2003 Jan;32(1):28-34
12525941
Acta Orthop. 2010 Jun;81(3):344-6
20450420