Osteotomy of the tibia for correction of complex deformity. (1/220)

Twenty complex tibial deformities due to anterior poliomyelitis in 18 patients were corrected by a modified O'Donoghue osteotomy. This technique allowed correction of the deformity in three planes. This was achieved by widening the rectangular window distally to correct both rotation and valgus and by trimming the anterior edges of the step cuts to correct flexion deformity. An above-knee cast was applied for eight to 13 weeks and the patients followed up for a mean of 3.2 years. One of the 18 patients developed delayed union because of fracture of the medial limb of the step cut. The results showed excellent correction of the three-plane deformity and there was no recurrence. This method of osteotomy is a safe and simple procedure which does not require internal fixation and allows correction of torsional and angular deformity.  (+info)

The mechanism of the effect of obesity in knee osteoarthritis: the mediating role of malalignment. (2/220)

OBJECTIVE: Obesity is most strongly linked to osteoarthritis (OA) at the knee. Varus malalignment was examined as a possible local mediator that may increase the impact of body weight at the knee, versus the hip or ankle. Compartment load distribution is more equitable in valgus than in varus knees, and valgus knees may better tolerate obesity. We therefore tested whether 1) body mass index (BMI) is correlated with OA severity in varus knees, 2) the BMI-OA severity correlation is weaker in valgus than in varus knees, 3) BMI is correlated with the severity of varus malalignment, and 4) the BMI-medial tibiofemoral OA severity relationship is reduced after controlling for varus malalignment. METHODS: In 300 community-recruited patients with knee OA, 2 groups (varus and valgus) were identified based on dominant knee alignment on a full-limb radiograph, i.e., the angle formed by the intersection of the femoral and tibial mechanical axes. Severity of knee OA was assessed by measurement of the narrowest joint space width on radiographs of knees in a fluoroscopy-confirmed semiflexed position. RESULTS: Alignment direction was symmetric (or neutral in 1 limb) in 87% of patients. One hundred fifty-four patients had varus knees and 115 had valgus knees. BMI correlated with OA severity in the varus group (r = -0.29, P = 0.0009) but not in the valgus group (r = -0.13, P = 0.17). BMI correlated with malalignment in those with varus knees (r = 0.26) but not in those with valgus knees (r = 0.16). The partial correlation of BMI and OA severity, controlling for sex, was reduced from 0.24 (P = 0.002) to 0.04 (P = 0.42) when varus malalignment was added to the model. CONCLUSION: BMI was related to OA severity in those with varus knees but not in those with valgus knees. Much of the effect of BMI on the severity of medial tibiofemoral OA was explained by varus malalignment, after controlling for sex. Whether it precedes or follows the onset of disease, varus malalignment is one local factor that may contribute to rendering the knee most vulnerable to the effects of obesity.  (+info)

Open-wedge osteotomy by hemicallotasis or the closed-wedge technique for osteoarthritis of the knee. A randomised study of 50 operations. (3/220)

We describe the results of 50 operations carried out on 46 patients with medial osteoarthritis of the knee of Ahlback grade 1 to 3. Patients were randomised either to a closed-wedge high tibial osteotomy (HTO) or an open-wedge procedure based on the hemicallotasis technique (HCO). Their median age was 55 years (38 to 68). The preoperative median hip-knee-ankle (HKA) angle was 171 degrees (164 to 176) in the HTO group and 173 degrees (165 to 179) in the HCO group. After six weeks, the median HKA angle was 185 degrees (176 to 194) in the HTO group and 184 degrees (181 to 188) in the HCO group. In the HTO group, seven patients were within the range of 182 degrees to 186 degrees compared with 21 in the HCO group (p < 0.001). One year later, ten HTO patients were within this range while the HKA angulation in the HCO group was unchanged. At two years the numbers were 11 and 18, respectively. We evaluated the clinical results on the Hospital for Special Surgery, Lysholm and Wallgren-Tegner activity scores, and patients completed part of the Nottingham Health Profile questionnaire. An impartial observer at the two-year follow-up concluded that all scores had improved, but found no clinical differences between the groups.  (+info)

Hemicallotasis open-wedge osteotomy for osteoarthritis of the knee. Complications in 308 operations. (4/220)

We studied the complications after open-wedge osteotomy by hemicallotasis in 308 consecutive patients, most of whom had osteoarthritis of the knee. The participating surgeons, who worked at 17 hospitals, used their discretion in selecting patients, operating techniques and external fixators. The general complications included 11 cases of deep-vein thrombosis (4%), six of nonunion (2%) and one of septic arthritis of the knee. There were technical complications in 13 patients (4%). In 157 patients (51%) pin-site infections were recorded; of these, 96% were minor and responded to wound toilet and antibiotic treatment. A total of 18 revision procedures was carried out.  (+info)

The sulcus angle and malalignment of the extensor mechanism of the knee. (5/220)

Anterior knee pain due to dysplasia of the extensor mechanism is common. We have studied 137 knees (103 patients) in order to identify a rapid and reproducible radiological feature which would indicate the need for further analysis. Overall, 67 knees (49%) had at least one radiological abnormality; 70 (51%) were considered normal. There were five cases of Dejour type-3 dysplasia of the femoral trochlea, nine of type-2 and 12 of type-1. There were 49 cases of patella alta and five of patella infera. Four knees had an abnormal lateral patellofemoral angle (patellar tilt), and in 15 knees there was more than one abnormality. Classification of trochlear dysplasia was difficult and showed poor reproducibility. This was also true for the measurement of the lateral patellofemoral angle. Patellar height was more easily measured but took time. The sulcus angle is an easily and rapidly measurable feature which was reproducible and was closely related to other features of dysplasia of the extensor mechanism. The finding of a normal sulcus angle suggested that seeking other radiological evidence of malalignment of the extensor mechanism was unlikely to reveal additional useful information. The severity of other features of dysplasia of the extensor mechanism correlated with increasing sulcus angle.  (+info)

MRI study of talonavicular alignment in club foot. (6/220)

We studied in vivo the talonavicular alignment of club foot in infants using MRI. We examined 26 patients (36 feet) with congenital club foot. The mean age at examination was 9.0 months (4 to 12). All analyses used MRI of the earliest cartilaginous development of the tarsal bones in the transverse plane, rather than the ossific nucleus. The difference in the mean talar neck angle (44.0 +/- 8.1 degrees) in club foot was statistically significant (p < 0.001) when compared with that of the normal foot (30.8 +/- 5.5 degrees). The difference between the mean angles in the group treated by operation (47.9 +/- 6.7 degrees) and those treated conservatively (40.1 +/- 7.5 degrees) was also statistically significant. The anatomical relationship between the head of the talus and the navicular was divided into two patterns, based on the position of the mid-point of the navicular related to the long axis of the head. In the operative group, 18 feet were classified as having a medial shift of the navicular and none had a lateral shift. In the conservative group, 12 showed a medial shift of the navicular and six a lateral shift. All nine unaffected normal feet in which satisfactory MRI measurements were made showed a lateral shift of the navicular. Club feet had a larger talar neck angle and a more medially deviated navicular when compared with normal feet. This was more marked in the surgical group than in the conservative group.  (+info)

Computerised measurement of tibiofemoral alignment. (7/220)

Tibiofemoral alignment has a direct correlation with the survival of total knee arthroplasty. Traditionally, it has been measured using a goniometer on radiographs. We describe new software which measures this alignment on scanned radiographs by automatically detecting bones in the image. Two surgeons used conventional methods and two clerical officers used the computerised routine to assess 58 radiographs of the knee on two occasions. There were no significant differences between any of the paired comparisons. The largest mean difference detected was 1.19 degrees. Across all comparisons, the mean correlation was 0.755. A standardised routine for measuring tibiofemoral alignment was the greatest factor in reducing error in our study. These results show that non-medical staff can reliably use the software to measure tibiofemoral alignment. It has the potential to measure all the parameters recommended by the Knee Society.  (+info)

Fracture of the proximal tibia six months after Fulkerson osteotomy. A report of two cases. (8/220)

The Fulkerson osteotomy has proved to be a reliable treatment for subluxation of the patella due to malalignment. Aggressive rehabilitation in the early postoperative period is unwise since the proximal tibia is weakened by the oblique osteotomy. Early weight-bearing and unrestricted activity have caused fractures in a few patients. Even late in the postoperative period the osteotomy may adversely influence the biomechanical properties of the proximal tibia. We describe two athletes who sustained a fracture of the proximal tibia, during recreational activities, six months after a Fulkerson osteotomy. Both had been bearing full weight for about ten weeks without complaint. Bony healing of the osteotomy had been demonstrated on plain radiographs at ten and at 12 weeks. After a Fulkerson osteotomy, jogging and activities which impose considerable impact force should be discouraged for at least nine to 12 months.  (+info)