Ann Rheum Dis: first published as 10.1136/ard.28.4.359 on 1 July 1969. Downloaded from Ann. rheum. Dis. (1969), 28, 359 LONG LEG ARTHROPATHY* BY A. ST. J. DIXON AND S. CAMPBELL-SMITH Bath There are now abundant examples of the way in Thus Coste and Forestier (1935) showed that hemi- which mechanical factors concerned with the use of plegia protected against the development of Heber- a limb influence the pattern and severity of subse- den's nodes and Glyn, Sutherland, Walker, and quent joint disease irrespective of diagnosis, both in Young (1966) that the joints of the paralysed limb inflammatory arthritis and non-inflammatory arth- in poliomyelitis had less tendency to arthrosis than rosis. For example, Jacqueline (1953) noted that, the non-paralysed joints. Similarly over-use of a in hemiplegic patients who subsequently developed joint with arthrosis increases the size of osteophytic rheumatoid arthritis, the paralysed side did not outgrowths. develop the clinical or radiological changes of This paper describes a common mechanical altera- rheumatoid arthritis, although biopsy (Thompson tion in the use of the knee which predisposes this and Bywaters, 1963) showed the synovium to be joint to more severe disease. This disordered gait affected. Similarly, disuse of a limb because of a occurs when a patient walks for a number of years copyright. lower motor neurone lesion such as poliomyelitis with an uncorrected inequality of leg length and will also protect against the subsequent development results in selective damage to the knee of the longer of rheumatoid arthritis (Secondo, Barboso, and leg. We have observed this whether the inequality Mellini, 1967). Kamermann (1966) showed that of leg length is apparent (due to hip contracture) disuse due to previous trauma will have the same or real (due to a true reduction in leg length) and effect. Courtright and Kuzell (1965) confirmed this whether it is due to damage to one hip from previous sparing effect of disuse in another patient and also infection, arthritis, congenital dysplasia, or trauma. in experimental adjuvant arthritis in rats. Con- Whatever the predisposing cause, the knee in the http://ard.bmj.com/ versely, increased use of a joint increases the fre- seemingly longer leg is then used abnormally. This quency and severity of arthritis. Thus, by using brings about more severe arthritis of the knee if the careful grading systems, Rotes Querol and patient is affected by rheumatoid arthritis, or more Roig-Escofet (1968) showed that there is usually precocious arthrosis of the knee if the patient is a more severe arthritis in the joints of the right than affected by osteoarthrosis. We refer to this as of the left hand. Van Dam (1964) and Soila (1963) "long leg arthropathy". published similar findings with regard to radiological on October 2, 2021 by guest. Protected erosions of articular bone in rheumatoid arthritis. Case Reports Castillo, El Sallab, and Scott (1965) noted that Brief case histories illustrate the association: manual workers developed larger, more "cystic" (1) A 45-year-old woman developed tuberculosis of the erosions compared with non-manual workers left hip when she was 14 years old. This healed, but she affected by rheumatoid arthritis. We have observed thereafter walked without correction of the short left that, when patients develop ulnar deviation of the leg. At the age of 40 she noted a painful right knee. Fig. 1 (overleaf) shows the problem. There is about 5 fingers, it more frequently affects the right hand cm. of difference in leg length. The right knee shows before the left. Lindsay (1913) found involvement destruction of the lateral tibial compartment characteris- of the small joints of the hand to be more frequent on tic of long leg arthropathy. Clinically the knee was the right than on the left side in gout. slightly swollen and laterally hypermobile and showed In arthrosis similar observations have been made. some valgus and flexion deformity. Clinical and cinematographic studies have shown * Paper presented at a meeting of the Heberden Society on May 17 1968. that such patients walk with the "longer" leg flexed 359 360 ANNALS OF THE RHEUMATIC DISEASES Ann Rheum Dis: first published as 10.1136/ard.28.4.359 on 1 July 1969. Downloaded from Fig. I .-Case 1, a woman aged 45. Tuberculosis of left hip at age 14. Subsequently walked with uqcorrected inequality of leg length. Note changes in knee of longer leg. copyright. and externally rotated at the hip and flexed at the (4) A 62-year-old woman with congenital dislocation of knee. During walking a strain is thrown on the the hips, developed generalized osteoarthrosis at the age http://ard.bmj.com/ knee so that it tries to bend into a valgus position. of 40 and shortening of the left hip at the age of 52 years. This repeated valgus strain may be the cause of the She now complains of more pain in the right (contra- damage we are describing. lateral) knee which has become subject to repeated effusions. This knee already shows increased lateral Four further patients show illustrative cases of mobility compared with the left. Fig. 4 (overleaf) con- varied aetiology. trasts the radiological appearance of the lateral tibio- femoral compartments of the two knees. (2) A 69-year-old woman has bilateral coxarthrosis. A (5) A 67-year-old woman had osteoarthrosis of the left on October 2, 2021 by guest. Protected Smith-Peterson cup arthroplasty had been inserted on hip with an abduction deformity causing an apparent the left without correction of 4-5 cm. inequality of leg left leg lengthening of 4-5 cm. In this instance it was length. She has arthrosis in both knees, but the left the ipsilateral knee of the longer left leg which became knee does not trouble her while the right knee is painful painful and swollen and showed the radiological changes and shows more severe changes in the lateral compart- of osteoarthrosis. ment (Fig. 2, opposite). Merely to select certain patterns of joint disease (3) A 60-year-old woman gave a 10-year history of does not prove their significance. Therefore two rheumatoid arthritis with symmetrical involvement of further studies have been done to discover whether the knees until there was destruction of the right hip the association is true or due to selection. with protrusio acetabuli and shortening of the right leg if there were no association of by 4 cm. This has been associated with the subsequent We have argued development of valgus instability and increased radiolo- knee arthropathy with the longer leg, patients who gical change in the left knee, which is now much more have primary shortening of one leg and who sub- painful than the right (Fig. 3, overleaf). sequently developed knee pain should do so with Ann Rheum Dis: first published as 10.1136/ard.28.4.359 on 1 July 1969. Downloaded from LONG LEG ARTHROPATHY 361 copyright. Fig. 2.-Case 2, a woman aged 69. Bilateral coxarthrosis. Left Smith Peterson cup arthroplasty without correction of unequal leg length. Arthrosis is present in both knees, but only the right is painful and swollen. equal frequency in either knee. This proposition knees and had minor bilateral patello-femoral osteo- http://ard.bmj.com/ was tested in two separate surveys. arthrosis. Eight complained of pain in the knee of the shorter leg, so casting doubt on the validity of I. The first survey was done at the Winford our thesis. However, on examination, these knees Orthopaedic Hospital. 224 case histories of patients were all clinically normal and the pain was anterior known to haveunilateral hip disease in childhood and thigh pain referred from the damaged hip. One now over the age of 20 years were found in the of these eight patients had had two episodes of were hospital records and nineteen other patients locking in the ipsilateral knee. Nine of the eighteen on October 2, 2021 by guest. Protected seen in an appliance clinic attending for raised shoes. patients complained of pain in the contralateral knee From amongst these, by means of a questionnaire, and only three of these knees were clinically normal, we found 33 patients who fulfilled the following six showing painful valgus deformity with or without criteria: instability and three of these six knees showed radio- logical damage. In two of these this was confined (i) They had real or apparent leg inequality of leg length to the lateral tibio-femoral compartment. None of 2 5 cm. or more. of these patients had rheumatoid arthritis. (ii) They had subsequently walked with this uncorrected To summarize this first survey, in patients who had inequality of leg length for at least a year. shortening of 2 5 cm. of leg length or more and who (iii) They had subsequently developed symptoms (pain, subsequently developed pain in the knees, objective swelling, stiffness) in the knees. changes were almost always confined to the knee of the longer leg. Of these 33, eighteen accepted re-examination and fifteen refused or lived too far away. Of the eigh- II. The next survey was a 6-month period-of- teen re-examined, one complained of pain in both time study of all consecutive in-patients and out- Ann Rheum Dis: first published as 10.1136/ard.28.4.359 on 1 July 1969. Downloaded from 362 ANNALS OF THE RHEUMATIC DISEASES copyright. Fig. 3.-Case 3, a woman aged 60. Rheumatoid arthritis with symmetrical knee involvement until development of destructive shortening of right hip. Subsequently the left knee was more severely affected. patients at the Royal National Hospital for Rheu- http://ard.bmj.com/ matic Diseases, Bath, and all patients of certain orthopaedic and geriatric wards in neighbouring hospitals.