OBJECTIVETo observe the long-term outcome of high tibial osteotomy (HTO) in treating medial compartment osteoarthrosis of knees.

METHODSA retrospective study was carried out on 194 patients (215 knees) treated with HTO for medial compartment osteoarthritis at the Orthopaedic Hospital of Kiel University between 1985 and 1996.

RESULTSOne hundred and sixty-one knees (144 patients) were followed up for 1.5-12 years with an average of 7.5 years and their data were reviewed. The proportion of excellent outcome were 97.3%, 93.6% and 78.2% two, five and over five years after HTO, respectively. The revision rate of total knee arthroplasty (TKA) was 11.8% (19 knees retreated with TKA for HTO failure). The survivorship analysis of the 19 knees retreated with TKA showed an expected survival rate of 98.7%, 95.0% and 84.1% 2, 5 and 10 years after HTO, respectively. There were 5.6% complications (12/161), including five superficial wound infections, one deep infection, five delayed bone healing, and one peroneal nerve palsy. Fifty patients (54 knees) missed follow-up, among them 10 patients (11 knees) died.

CONCLUSIONSHTO is an effective method in treating medial compartment osteoarthritis with a varus knee. Appropriate overcorrection of femorotibial alignment is the key for the success of the operation. But as the long-term effect is concerned, there is a trend of deterioration and some of the patients may have a second operation of revision with TKA.

Adult ; Aged ; Bone Malalignment ; complications ; etiology ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Osteoarthritis, Knee ; diagnostic imaging ; surgery ; Osteotomy ; Radiography ; Recurrence ; Tibia ; surgery

BACKGROUND: We hypothesized that a number of clinical and radiologic parameters could influence the reducibility of varus deformity in total knee arthroplasty. The aim of this study was to identify the factors correlated with reducibility of varus deformity and predict more accurately the amount of medial soft tissue release required in varus deformity total knee arthroplasty. METHODS: One hundred forty-three knees with preoperative varus alignment and medial osteoarthritis were included in this retrospective study. The total knee arthroplasties were performed using a navigation system (OrthoPilot) by single surgeon. To assess varus deformity, the authors measured preoperative mechanical axis angles and valgus stress angles. Mechanical tibial angles, mechanical femoral angles, femoral osteophyte sizes, and tibial osteophyte sizes were measured. The Ahlback grading scale was applied for radiologic parameters, and clinical parameters (age, body mass index, sex, duration of pain, and preoperative range of motion) were documented. Correlations between these factors and preoperative valgus stress angle were analyzed. RESULTS: A negative correlation was found between preoperative mechanical axis angle and preoperative valgus stress angle (p < 0.01, r = -0.38), and a positive correlation was found between the preoperative mechanical tibial angle and preoperative valgus stress angle (p = 0.01, r = 0.19). CONCLUSIONS: The present study shows that preoperative varus deformity and proximal tibial vara (measured by preoperative mechanical axis angle and mechanical tibial angle, respectively) are correlated with reducibility of varus deformity (measured by preoperative valgus stress angle), and clinical parameters (age, range of motion, duration of pain and body mass index) and other radiologic parameters (osteophyte size, severity of osteoarthritis and angulation of distal femoral joint surface) were not significantly correlated with reducibility of varus deformity.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/*methods ; Bone Malalignment/radiography/*surgery ; Female ; Humans ; Knee Joint/radiography/*surgery ; Male ; Middle Aged ; Osteoarthritis, Knee/radiography/*surgery ; Retrospective Studies ; Stereotaxic Techniques ; Surgery, Computer-Assisted

PURPOSE: To identify the accuracy of postoperative implant alignment in minimally invasive surgery total knee arthroplasty (MIS-TKA), based on the degree of varus deformity. MATERIALS AND METHODS: The research examined 627 cases of MIS-TKA from November 2005 to December 2007. The cases were categorized according to the preoperative degree of varus deformity in the knee joint in order to compare the postoperative alignment of the implant: less than 5degrees varus (Group 1, 351 cases), 5degrees to less than 10degrees varus (Group 2, 189 cases), 10degrees to less than 15degrees varus (Group 3, 59 cases), and 15degrees varus or more (Group 4, 28 cases). RESULTS: On average, the alignment of the tibial implant was 0.2+/-1.4degrees, 0.1+/-1.3degrees, 0.1+/-1.6degrees, and 0.3+/-1.7degrees varus, and the tibiofemoral alignment was 5.2+/-1.9degrees, 4.7+/-1.9degrees, 4.9+/-1.9degrees, and 5.1+/-2.0degrees valgus for Groups 1, 2, 3, and 4, respectively, in the preoperative stage, indicating no difference between the groups (p>0.05). With respect to the accuracy of the tibial implant alignment, 98.1%, 97.6%, 87.5%, and 86.7% of Groups 1, 2, 3, and 4, respectively, had 0+/-3degrees varus angulation, demonstrating a reduced level of accuracy in Groups 3 and 4 (p<0.0001). There was no difference in terms of tibiofemoral alignment, with 83.9%, 82.9%, 85.4%, and 86.7% of each group, respectively, showing 6+/-3degrees valgus angulation (p>0.05). CONCLUSION: Satisfactory component alignment was achieved in minimally invasive surgery in total knee arthroplasty, regardless of the degree of varus deformity.
Aged ; Arthroplasty, Replacement, Knee/*methods ; Bone Anteversion/complications/*radiography ; Bone Malalignment/etiology/*radiography ; Female ; Humans ; Joint Deformities, Acquired/*surgery ; Knee Joint/radiography/*surgery ; Knee Prosthesis ; Male ; Middle Aged ; Minimally Invasive Surgical Procedures/*methods ; Osteoarthritis, Knee/complications/radiography/*surgery ; Postoperative Period ; Preoperative Period ; Range of Motion, Articular ; Tibia/surgery ; Treatment Outcome