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Inclination of the joint line in supracondylar osteotomy of the femur for valgus deformity
The Knee 11 (2004) 319–321
Inclination of the joint line in supracondylar osteotomy of the femur for valgus deformity Ricardo Navarro, Mario Carneiro* ˜ Paulo, Escola Paulista de Medicina, Rua Macau 300, Sao ˜ Paulo, Department of Orthopedics and Traumatology, Universidade Federal de Sao SP, 04032-020, Brazil Received 14 June 2003; received in revised form 7 July 2003; accepted 9 September 2003
Abstract The inclination of the joint line after supracondylar osteotomy of the femur for valgus deformity was studied in 22 patients and 26 knees. The patients (four males and 18 females) were 17–77 years old (mean, 49.5 years). The obliquity of the joint line was measured in positive degrees (medial inclination) and negative degrees (lateral inclination). Mean obliquity was q3.18 in the pre-operative study and y2.08 in the post-operative study. A more horizontal joint line was obtained following surgical treatment (mean correction: 5.08). 䊚 2003 Elsevier B.V. All rights reserved. Keywords: Valgus deformity; Supracondylar osteotomy; Joint line
1. Introduction
mity leads to a more horizontal joint line when the patient is weightbearing.
Several investigators consider evaluation of the obliquity of the joint line to be important in the study of genu valgum w5x. Closing wedge tibial osteotomy for valgus deformity frequently causes an increase in inferomedial inclination w1,2,6,8–11,15x. In computerized biomechanical studies, Coventry w12x demonstrated that tibial osteotomy for deformity causes an increase in joint obliquity, thus transferring most of the load from the lateral compartment to the intercondylar eminence of the tibia, with a consequent damaging affect on the joint. Maquet w9x stated that the resultant of the forces that act on the joint line will act in a perpendicular manner only after supracondylar osteotomy for valgus deformity, with an even distribution through the tibial condyles. The objective of the present study was to show that supracondylar osteotomy of the femur for valgus defor-
2. Methods
*Corresponding author. E-mail address: [email protected] (M. Carneiro).
Twenty-two adult patients were submitted to 26 interventions for the correction of valgus axial deviation associated or not with other pathologies. The patients are registered in the Departament of Orthopedics and ˜ PauloTraumatology of Universidade Federal de Sao Escola Paulista de Medicina. Four patients (18.2%) were males and eighteen (81.8%) were females, aged 17–77 years (mean ages 49.5 years). Knees were involved in 4 patients (18.2%), the right knee was involved in 18 (72.7%), and the left knee in 6 (27.3%). All patients were submitted to correction of the deformity by supracondylar medial closing wedge osteotomy of the femur using an anterior approach and lateral fixation with a 908 angle self-compressing plate. The valgus deformity was calculated for all patients using the femoral–tibial anatomical axis. Radiographic measurements were made through weight bearing films
0968-0160/04/$ - see front matter 䊚 2003 Elsevier B.V. All rights reserved. doi:10.1016/j.knee.2003.09.007
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R. Navarro, M. Carneiro / The Knee 11 (2004) 319–321
Fig. 1. Weight bearing radiograph showing pre-operative obliquity of the joint line. a – line parallel to the ground. b – line parallel to the tibial condyles determines the joint line obliquity. Medial obliquity determines a positive angle.
on bi-pedal stance. After the degree of deformity was measured, the wedge was calculated so as to yield a 58 valgus femoro–tibial anatomical axis. The obliquity of the joint line was measured in positive degrees to medial inclination and negative degrees to lateral inclination (Fig. 1). Mean pre-operative obliquity ranged from y3 to q188 (meansq3.18) (Table 1). Data were analyzed statistically by the non-parametric Wilcoxon test (T satistic) for two dependent samples according to Siegel w7x to compare the pre-operative and post-operative periods in terms of the variable under study. The level of significance was set at aF0.05. 3. Results Post-operative obliquity ranges from y7 to q78 (meansy28); the Wilcoxon test showed that the postoperative values significantly lower compared to preoperative values (Table 1) (Fig. 2)
Fig. 2. Weight bearing radiograph showing post-operative obliquity of the joint line. a – line parallel to the ground. b – line parallel to the tibial condyles determines the joint line obliquity.
4. Discussion In the past, osteotomy for the correction of genu valgum was preferentially performed on the tibia. However, starting in the 1960s, biochemical studies and the evaluation of long-term results led surgeons to begin to indicate osteotomy in the supracondylar region of the femur w1,13,14,16–18x. Our objective was to achieve a correction that would provide a femoro-tibial angle with valgus of approximately 58, as recommended by Shoji and Insall w4x and Coventry w3,12x. Mean pre-operative obliquity was q3.18 and mean post-operative obliquity was y2.08. The mean difference between the pre-operative and post-operative periods was 5.18, i.e. a lateral rotation of the joint line occurred. The Wilcoxon test showed that post-operative values were significantly lower than pre-operative values, confirming the facts that supracondylar osteotomy of the femur for valgus deformity produced horizontally
R. Navarro, M. Carneiro / The Knee 11 (2004) 319–321
of the joint line. This results in proportional redistribution of the forces that act on the medial and lateral compartments of the knee and represents one of the favorable consequences of this type of surgery.
Table 1 Patients submitted to supracondylar osteotomy of the femur for valgus deformity according to number of order and valgus (degree) of joint line obliquity during the pre-operative and post-operative periods and differences between periods Patient number
Pre-operative obliquity
Post-operative Obliquity
D
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Mean
0 q2 0 q3 q4 q2 q3 0 q4 q4 y3 0 q12 q2 q8 q3 q3 0 q18 0 q3 q2 0 q3 q4 q4 q3.1
y2 y2 0 0 q1 y3 y3 y4 y3 0 y6 y4 q7 y2 0 y2 y4 y2 y7 0 y2 y4 0 y5 y1 y4 y2.0
2 4 0 3 3 5 6 4 7 4 3 4 5 4 8 5 7 2 25 0 5 6 0 8 5 8 5.1
Wilcoxon test: calculated T O*; critical T 73 before-after.
321
References w1x Jackson JP, Waugh W. Tibial osteotomy for osteoarthritis of the knee. J Bone Jt Surg 1961;43-B:746 –750. w2x Bauer GCH, Insall JN, Koshino T. Tibial osteotomy in gonarthrosis (osteoarthritis of the knee). J Bone Jt Surg 1969;51A:1545 –1563. w3x Coventry MB. Osteotomy about the knee for degenerative and rheumatoid arthritis. J Bone Jt Surg 1973;55-A:33 –48. w4x Shoji H, Insall JN. High tibial osteotomy for osteoarthitis of the knee with valgus deformity. J Bone Jt Surg 1973;55A:963 –973. w5x Insall JN, Shoji H, Mayer V. High tibial osteotomy. J Bone Jt Surg 1974;56-A:1397 –1405. w6x Kettemkamp DB, Leach RE, Nasca R. Pitfalls of proximal tibial osteotomy. Clin Orthop 1975;106:232 –241. w7x Siegel S. Estadistica no parametrica. Mexico, Trillas, 1975, 346 pp. w8x Harding ML. A fresh appraisal of tibial osteotomy for osteoarthritis of the knee. Clin Orthop 1976;114:223 –233. w9x Maquet P. The biomecanics of the knee and surgical possibilities of healing osteoarthritic knee joints. Clin Orthop 1980;146:102 –110. w10x Well D, Schneider M, Simon G. Les osteotomies ´ du genou dans le traitement de la gonartrose. Rev Chir Orthop 1981;67:119 –122. w11x Frederici A, Albanese L, Nasciuti M. Osteotomie del ginochio. Revisione critica delle tecniche e dei resultati. Minerva Ortoped 1982;33:541 –556. w12x Coventry MB. Current concepts review upper tibial osteotomy for osteoarthritis. J Bone Jt Surg 1985;67-A:1136 –1140. w13x Maquet P. The treatment of choice in osteoarthritis of the knee. Clin Orthop 1985;192:108 –112. w14x Aglietti P, Stringa G, Buzzi R, Pisaneschi A, Windsor RE. Correction of valgus knee deformity with a supracondylar osteotomy. Clin Orthop 1987;217:214 –220. w15x Coventry MB. Proximal tibial varus osteotomy for osteoarthritis of the lateral compartment of the knee. J Bone Jt Surg 1987;69-A:32 –38. w16x McDermoth AGP, Finklestein JA, Farine I, Boyton EL, McIntosh DL, Gross A. Distal femoral varus osteotomy for varus deformity of the knee. J Bone Jt Surg 1988;70-A:110 –116. w17x Learmonth ID. A simple technique for varus supracondylar osteotomy in genu valgum. J Bone Jt Surg 1990;72-B:235 – 237. w18x Insall JN. Osteotomy. In: Insall JN, Windsor RE, Scott WN, Kelly MA, Aglietti P, editors. 2nd ed. Surgery of the knee. New York: Churchill Livingstone, 1993. p. 635 –676.
Inclination of the joint line in supracondylar osteotomy of the femur for valgus deformity Ricardo Navarro, Mario Carneiro* ˜ Paulo, Escola Paulista de Medicina, Rua Macau 300, Sao ˜ Paulo, Department of Orthopedics and Traumatology, Universidade Federal de Sao SP, 04032-020, Brazil Received 14 June 2003; received in revised form 7 July 2003; accepted 9 September 2003
Abstract The inclination of the joint line after supracondylar osteotomy of the femur for valgus deformity was studied in 22 patients and 26 knees. The patients (four males and 18 females) were 17–77 years old (mean, 49.5 years). The obliquity of the joint line was measured in positive degrees (medial inclination) and negative degrees (lateral inclination). Mean obliquity was q3.18 in the pre-operative study and y2.08 in the post-operative study. A more horizontal joint line was obtained following surgical treatment (mean correction: 5.08). 䊚 2003 Elsevier B.V. All rights reserved. Keywords: Valgus deformity; Supracondylar osteotomy; Joint line
1. Introduction
mity leads to a more horizontal joint line when the patient is weightbearing.
Several investigators consider evaluation of the obliquity of the joint line to be important in the study of genu valgum w5x. Closing wedge tibial osteotomy for valgus deformity frequently causes an increase in inferomedial inclination w1,2,6,8–11,15x. In computerized biomechanical studies, Coventry w12x demonstrated that tibial osteotomy for deformity causes an increase in joint obliquity, thus transferring most of the load from the lateral compartment to the intercondylar eminence of the tibia, with a consequent damaging affect on the joint. Maquet w9x stated that the resultant of the forces that act on the joint line will act in a perpendicular manner only after supracondylar osteotomy for valgus deformity, with an even distribution through the tibial condyles. The objective of the present study was to show that supracondylar osteotomy of the femur for valgus defor-
2. Methods
*Corresponding author. E-mail address: [email protected] (M. Carneiro).
Twenty-two adult patients were submitted to 26 interventions for the correction of valgus axial deviation associated or not with other pathologies. The patients are registered in the Departament of Orthopedics and ˜ PauloTraumatology of Universidade Federal de Sao Escola Paulista de Medicina. Four patients (18.2%) were males and eighteen (81.8%) were females, aged 17–77 years (mean ages 49.5 years). Knees were involved in 4 patients (18.2%), the right knee was involved in 18 (72.7%), and the left knee in 6 (27.3%). All patients were submitted to correction of the deformity by supracondylar medial closing wedge osteotomy of the femur using an anterior approach and lateral fixation with a 908 angle self-compressing plate. The valgus deformity was calculated for all patients using the femoral–tibial anatomical axis. Radiographic measurements were made through weight bearing films
0968-0160/04/$ - see front matter 䊚 2003 Elsevier B.V. All rights reserved. doi:10.1016/j.knee.2003.09.007
320
R. Navarro, M. Carneiro / The Knee 11 (2004) 319–321
Fig. 1. Weight bearing radiograph showing pre-operative obliquity of the joint line. a – line parallel to the ground. b – line parallel to the tibial condyles determines the joint line obliquity. Medial obliquity determines a positive angle.
on bi-pedal stance. After the degree of deformity was measured, the wedge was calculated so as to yield a 58 valgus femoro–tibial anatomical axis. The obliquity of the joint line was measured in positive degrees to medial inclination and negative degrees to lateral inclination (Fig. 1). Mean pre-operative obliquity ranged from y3 to q188 (meansq3.18) (Table 1). Data were analyzed statistically by the non-parametric Wilcoxon test (T satistic) for two dependent samples according to Siegel w7x to compare the pre-operative and post-operative periods in terms of the variable under study. The level of significance was set at aF0.05. 3. Results Post-operative obliquity ranges from y7 to q78 (meansy28); the Wilcoxon test showed that the postoperative values significantly lower compared to preoperative values (Table 1) (Fig. 2)
Fig. 2. Weight bearing radiograph showing post-operative obliquity of the joint line. a – line parallel to the ground. b – line parallel to the tibial condyles determines the joint line obliquity.
4. Discussion In the past, osteotomy for the correction of genu valgum was preferentially performed on the tibia. However, starting in the 1960s, biochemical studies and the evaluation of long-term results led surgeons to begin to indicate osteotomy in the supracondylar region of the femur w1,13,14,16–18x. Our objective was to achieve a correction that would provide a femoro-tibial angle with valgus of approximately 58, as recommended by Shoji and Insall w4x and Coventry w3,12x. Mean pre-operative obliquity was q3.18 and mean post-operative obliquity was y2.08. The mean difference between the pre-operative and post-operative periods was 5.18, i.e. a lateral rotation of the joint line occurred. The Wilcoxon test showed that post-operative values were significantly lower than pre-operative values, confirming the facts that supracondylar osteotomy of the femur for valgus deformity produced horizontally
R. Navarro, M. Carneiro / The Knee 11 (2004) 319–321
of the joint line. This results in proportional redistribution of the forces that act on the medial and lateral compartments of the knee and represents one of the favorable consequences of this type of surgery.
Table 1 Patients submitted to supracondylar osteotomy of the femur for valgus deformity according to number of order and valgus (degree) of joint line obliquity during the pre-operative and post-operative periods and differences between periods Patient number
Pre-operative obliquity
Post-operative Obliquity
D
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Mean
0 q2 0 q3 q4 q2 q3 0 q4 q4 y3 0 q12 q2 q8 q3 q3 0 q18 0 q3 q2 0 q3 q4 q4 q3.1
y2 y2 0 0 q1 y3 y3 y4 y3 0 y6 y4 q7 y2 0 y2 y4 y2 y7 0 y2 y4 0 y5 y1 y4 y2.0
2 4 0 3 3 5 6 4 7 4 3 4 5 4 8 5 7 2 25 0 5 6 0 8 5 8 5.1
Wilcoxon test: calculated T O*; critical T 73 before-after.
321
References w1x Jackson JP, Waugh W. Tibial osteotomy for osteoarthritis of the knee. J Bone Jt Surg 1961;43-B:746 –750. w2x Bauer GCH, Insall JN, Koshino T. Tibial osteotomy in gonarthrosis (osteoarthritis of the knee). J Bone Jt Surg 1969;51A:1545 –1563. w3x Coventry MB. Osteotomy about the knee for degenerative and rheumatoid arthritis. J Bone Jt Surg 1973;55-A:33 –48. w4x Shoji H, Insall JN. High tibial osteotomy for osteoarthitis of the knee with valgus deformity. J Bone Jt Surg 1973;55A:963 –973. w5x Insall JN, Shoji H, Mayer V. High tibial osteotomy. J Bone Jt Surg 1974;56-A:1397 –1405. w6x Kettemkamp DB, Leach RE, Nasca R. Pitfalls of proximal tibial osteotomy. Clin Orthop 1975;106:232 –241. w7x Siegel S. Estadistica no parametrica. Mexico, Trillas, 1975, 346 pp. w8x Harding ML. A fresh appraisal of tibial osteotomy for osteoarthritis of the knee. Clin Orthop 1976;114:223 –233. w9x Maquet P. The biomecanics of the knee and surgical possibilities of healing osteoarthritic knee joints. Clin Orthop 1980;146:102 –110. w10x Well D, Schneider M, Simon G. Les osteotomies ´ du genou dans le traitement de la gonartrose. Rev Chir Orthop 1981;67:119 –122. w11x Frederici A, Albanese L, Nasciuti M. Osteotomie del ginochio. Revisione critica delle tecniche e dei resultati. Minerva Ortoped 1982;33:541 –556. w12x Coventry MB. Current concepts review upper tibial osteotomy for osteoarthritis. J Bone Jt Surg 1985;67-A:1136 –1140. w13x Maquet P. The treatment of choice in osteoarthritis of the knee. Clin Orthop 1985;192:108 –112. w14x Aglietti P, Stringa G, Buzzi R, Pisaneschi A, Windsor RE. Correction of valgus knee deformity with a supracondylar osteotomy. Clin Orthop 1987;217:214 –220. w15x Coventry MB. Proximal tibial varus osteotomy for osteoarthritis of the lateral compartment of the knee. J Bone Jt Surg 1987;69-A:32 –38. w16x McDermoth AGP, Finklestein JA, Farine I, Boyton EL, McIntosh DL, Gross A. Distal femoral varus osteotomy for varus deformity of the knee. J Bone Jt Surg 1988;70-A:110 –116. w17x Learmonth ID. A simple technique for varus supracondylar osteotomy in genu valgum. J Bone Jt Surg 1990;72-B:235 – 237. w18x Insall JN. Osteotomy. In: Insall JN, Windsor RE, Scott WN, Kelly MA, Aglietti P, editors. 2nd ed. Surgery of the knee. New York: Churchill Livingstone, 1993. p. 635 –676.