Between June 1993 and December 1994, we performed
total knee arthroplasty (TKA) on 27 knees in 24 patients with spontaneous bony
ankylosis in severe flexion. The mean age at operation was 43.5 years (30 to 60). No patient had preoperative
pain. Three were unable to walk and 21 could manage less than five blocks. The mean duration of the
ankylosis was 18.7 years (13 to 25) and its mean position was 105 degree flexion (75 to 135). The preoperative Hospital for Special Surgery Knee Score of 60 points was improved to 87 at the final follow-up three to five years later. All knees were free from
pain. The mean range of active flexion in 24 knees was 97 degrees (78
to 115) and the mean
arc of movement 91 degrees (78 to 98). The mean fixed flexion
deformity was 6 degrees (0 to 25) and the extension lag 8 degrees (0 to 25). Angular
deformity was corrected to between 0 degrees and 10 degrees of valgus. Four patients were able to walk one block and 20 five to seven blocks. Thirteen knees (48%) showed some
necrosis at the skin edge; one knee required
arthrodesis and another resection
arthroplasty. One had a recurrence of tuberculous
infection requiring
arthrodesis. One patient had a
rupture of the quadriceps tendon. To date no
prosthesis has required revision for loosening. Radiolucency of 1 mm or less about the tibial
prosthesis was observed at follow-up in four of the 24 knees. Our results have shown that one-stage TKA and skeletal
traction after operation can achieve correction of severe flexion
deformity of the knee with marked improvement in the function and quality of life.