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Two cases of hypertrophic nonunion of the tibia with deformity for which distraction treatment using an Ilizarov/Taylor Spatial Frame (Smith & Nephew, Memphis, TN) are presented. This frame utilizes a computer program to help plan correction of the deformity.
A case of deformity and shortening after post-traumatic growth arrest treated using the Taylor Spatial Frame (Smith & Nephew, Tennessee, USA) is presented. This is the first report showing the application of the frame for post-traumatic deformity in the distal femur, and successful outcomes promise utilization of the frame even for correction of severe deformity in the distal femur.
INTRODUCTION: The outcomes of 106 total knee arthroplasties implanted using a soft tissue balancing surgical technique at one surgical centre were used to assess the accuracy maintaining the knee's original joint line (JL). The aim of the study was to determine whether there is a shift of the presumed joint line after surgery. MATERIALS AND METHODS: Preoperative and post-operative radiographs were compared to determine any changes in the articulation height. The preoperative distance of the fibular head to the natural joint line was measured and compared with the post-operative measurement of the fibular head to the femoral articulation line (measured on the radiograph and defined as Rxmm). Based on the actual medio-lateral dimension of the tibial metal back, the measured difference (RXmm) could be converted into true distances (in mm). The Blackburn-Peel index was assessed as an additional outcome prior to and following surgery. RESULTS: Preoperatively, the average distance from the fibular head to the joint line was 15.1 Rxmm (SD 4.3) while the post-surgical distance was 15.5 Rxmm (SD 5.6). The average deviation of the post-surgical JL in relation to the original JL amounted to 0.4 Rxmm (SD 3.7). The average deviation of the joint line converted into the true distance was -0.3 mm (with a range of -5.9 mm in distal direction to + 8.3 mm in the proximal direction). Valgus position appeared to generate rather a shift in proximal direction whereas varus deformity favours a shift in distal direction. Seven patients exhibited a deviation of more than 5 mm in either the distal or proximal direction. All of the patients of this subgroup had a preoperative anatomical abnormality including a severe malalignment, serious bone destruction or had previously undergone a high tibial osteotomy. CONCLUSION: An exact reconstruction of the natural Joint Line is achievable when using the described soft tissue balancing surgical technique with the posterior cruciate ligament (PCL) retaining prosthesis design used in this series.
Shortening of the femoral neck and proximal displacement of the greater trochanter are the principal complications following avascular necrosis of the capital epiphysis head in early childhood. We report here the long-term follow-up of a series of osteotomies performed to lengthen the femoral neck and thus to restore the normal anatomy and function of the hip joint. Out of a sample of 24 patients, 15 (62.5%) were reviewed at the end of a mean follow-up of 10 years and 2 months. Fourteen of them (93.3%) had originally complained of pain on walking which varied in severity. After the operation, five were free from pain at the end of the follow-up, 9 still experienced pain on walking, and 1 also reported pain at rest. Before the operation, a positive Trendelenburg's sign was found in 8 of the patients. This was still present in 2 at follow-up. The average perpendicular distance from the center of the femoral head to a horizontal plane passing through the tip of the greater trochanter (the centro-trochanteric distance) was reduced from 33 mm to 7 mm. Apart from correcting the anatomical deformity, it is suggested that this operation may well provide lasting relief from pain and increase the power of the abductor muscles. It may also delay the onset of osteoarthritic change and in this way postpone the necessity for an endoprosthesis.
The purpose of this study was to evaluate the significance of the Q angle with respect to the patella position. Fifty-six knee joints of 34 patients (15 bilateral) with chronic patellofemoral pain were prospectively evaluated. All patients were examined by the same orthopaedic surgeon (R.M.B.) and the Q angle measured clinically and using long radiographs. Additionally, axial computed tomography (CT) scans were obtained through the center of the patellar articular cartilage in 0 degrees of flexion. Three different patellofemoral indices were measured by the second author (K.W.), who was not involved in the clinical examination: lateral patellar displacement (LPD), lateral patellar tilt (LPT), and patella-lateral condyle index (PLCI). These results were compared with the values of the measured Q angle. For statistical analysis, the Pearson correlation coefficient was calculated and the Statistical Package for Social Science (SPSS) used. A pvalue < 0.05 was considered significant. We could not find a significant correlation between the Q angle values and the patellofemoral indices in all patients (bilateral or only right/left). Within the patients with bilateral patellofemoral pain (n = 15), there was a significant correlation between LPD and PLCI (p = 0.015), LPT and PLCI (p = 0.024) left and LPD and LPT(p = 0.011) right. Similar results were found in patients with pain only on one side. In conclusion, there is no significance between the Q angle and the position of patella. The diagnostic relevance of the Q angle could not be established.
Acetabular, femoral and tibial torsion of 50 normal adult male subjects were measured by computerized tomography and the relationship between these angles and foot-progression angle was examined. The mean acetabular anteversion was 15.6 degrees on the right and 15.8 degrees on the left, (range 3 degrees-30 degrees). The mean femoral torsion was 6.5 degrees on the right and 5.8 degrees on the left (range 14 degrees-28 degrees). The mean tibiofibular torsion was 30.9 degrees on the right and 29.1 degrees on the left (range 16 degrees-50 degrees). Although the normal range of torsional measurements of the lower extremity was very broad, subjects usually had out-toeing, with a mean foot-progression angle of 13.7 degrees on the right and 13.0 degrees on the left (range 6 degrees-21 degrees). No correlation was detected on the rotation between different levels of the lower limb. No difference was detected in the lower extremity rotational profile between right and left sides.
BACKGROUND AND AIM: High tibial osteotomies attempt to recreate physiologically normal joint loading. Previous studies have discussed the influence of mal-alignment on the distribution of static loads to the medial and lateral compartments of the knee. The aim of this study was to determine the influence of mal-alignment on the tibio-femoral loading conditions during dynamic activities. MATERIAL AND METHODS: Using a musculo-skeletal model of the lower limb, which had been previously validated with in vivo data, in this study we modified the alignment of the knee in four patients, from a normal position to the extremes of 8 degrees valgus and 10 degrees varus mal-alignment. The resulting tibio-femoral joint contact forces were examined while patients were walking and stair climbing. RESULTS: Varying the mal-alignment resulted in a highly individual response in joint loads. Deviations from the normal alignment produced an increase in loading, with valgus generating a more rapid increase in loading than a varus deformity of the same amount. Varus deformities of 10 degrees resulted in increases in peak contact force from an average of 3.3-times bodyweight (BW) up to a peak of 7.4 BW (+45% to +114%) while patients were walking, whilst increases of 15% up to 35% were determined for stair climbing. Increases of up to 140% were calculated at 8 degrees valgus during walking and up to 53% for stair climbing. CONCLUSION: This study demonstrated a clear dependence of the individual joint loads on axial knee alignment. Based on the sensitivity of joint loading to valgus mal-alignment, more than 3 degrees of over-correction of a varus deformity to valgus should be carefully reconsidered.
In 1995, Eckhoff and colleagues demonstrated a new method for assessing relative rotational alignment of the femoral and tibial components in total knee arthroplasty (TKA). We studied the usefulness of a modified Eckhoff method. Five knee prostheses (Natural Knee, Deltafit, and three different sizes of Press-Fit Condylar) were used in an in-vitro study. A series of lateral radiographs were taken with the femoral component rotated in 1 degrees increments from 15 degrees internal rotation to 15 degrees external rotation. The rotation of the implant was calculated based on the geometric relationship of pegs that were present symmetrically on the medial and lateral sides of the femoral components in all prostheses. In a study of the clinical applications, two independent observers measured the relative rotation of 18 knees in 16 patients after TKA, using this method. In the in-vitro study, the measurement error of rotation averaged 0.27 degrees, and the maximum error was 0.96 degrees. Clinically, the mean difference between the measurements of the two observers in each knee was 0.64 degrees; there was a high correlation between the values measured by the two observers (r = 0.89; P<0.0001). This is a useful method for determining the relative rotation in TKA accurately and reproducibly.
We have recently developed a technique of per-cutaneous multidrilling osteotomy for limb lengthening and deformity correction. The bone is drilled percutaneously, using a special drill guide, and osteotomy is accomplished by connecting the multiple drill holes with a small chisel. The bone segments are subjected to slow progressive distraction with an external fixation device. We have lengthened 33 limbs in 22 patients with congenital or post-traumatic limb shortening and/or bone deformities. All the patients underwent the proposed lengthening and/or correction of the bone deformities through a single-treatment procedure. None of the lengthened segments resulted in nonunion. This technique can prevent undesirable bone cracks and preserve soft tissue around the osteotomy site, and is also applicable to other fields of orthopedic surgery.
The effect of anatomic variations on the operative techniques used in total knee arthroplasty (TKA) was assessed. In 133 Japanese patients with medial osteoarthritis (OA), six parameters were measured on anteroposterior radiographs of the lower extremities taken with the patients in the supine position. The results showed that the characteristics of the knees were bowing of the femoral shaft and proximal tibia vara, with lateral offset of the tibial shaft with respect to the center of the tibial plateau. The angle between a perpendicular to the mechanical axis and the tangent to the distal femoral condyles can be used in determining the external rotation of the femoral component. This angle was more than 3 degrees in 20% of the patients. The femoral component should therefore be externally rotated more than 3 degrees relative to the posterior condylar line in such patients. Because the center of the tibial plateau is located medial to the central line of the tibial shaft in knees with medial OA, the central point of the tibial articular surface should not be used for alignment of the tibial component. The medial offset stem of the tibial component may impinge against the medial wall. Anatomic variations should be evaluated before TKA is attempted.
The aim of the current study was to investigate posteromedial tibiofemoral congruence at full flexion of the knee in control knee joints and those affected by an isolated medial meniscal tear, to examine whether lack of such congruence was a causative factor in isolated medial meniscal tears. In this study, 1677 knee joints in 875 subjects were evaluated. The joints were classified as a control group (1345 joints), an isolated medial meniscal tear group (224 joints), and a contralateral isolated medial meniscal tear group (108 joints). Posteromedial tibiofemoral congruence was examined on a lateral radiograph of the knee joint at full flexion. The tangent touching the anterior and posterior parts of the articular surface of the medial tibial condyle was assumed to be the X-axis. To evaluate posteromedial tibiofemoral congruence, we measured the angle formed by the tangent that maximized the gradient of the tangent on the articular surface of the medial femoral condyle, and the tangent that maximized the gradient of the tangent on the articular surface of the medial tibial condyle. The mean angle differed significantly between the control and the isolated medial meniscal tear groups, regardless of sex. Isolated medial meniscal tears were found to be strongly related to an abnormally decreased angle, and, therefore, incongruence of the posteromedial tibiofemoral articulation at full flexion was considered to be one of the causes of isolated medial meniscal tears.
We performed a clinical and radiological analysis to evaluate the significance of the stem position of cementless CLS components with respect to function and survival. We used patient material from a multi-center study of 3,732 CLS stems with a mean follow-up of 43 months (range: 12-142 months). The clinical outcome was assessed using Merle D'Aubigné Scores and stem alignment was determined as the deviation of the longitudinal stem axis from the longitudinal femur axis. We found no correlation between stem alignment and function, survival, implant migration or periprosthetic radiolucent lines. In patients with rheumatoid arthritis and hip ankylosis the neutral stem position was less often achieved than in patients with other diagnoses. The results of our study cast doubt on whether the varus position of the femoral component of cementless tapered CLS-type stem designs is as critical as in cemented total hip arthroplasty.
In a prospective study, 645 consecutive Colles' fractures treated conservatively were followed until union. The fractures subsequently lost some of their manipulated position during the immobilization period. However, the anatomical end result was significantly improved compared with the initial deformity. The mean shortening of the radius during plaster-cast treatment was 3 mm, and the mean increase of dorsal angulation was 7 degrees. Multiple regression analyses showed that initial dorsal angulation, age, and Older type were important predictor variables for the end result of dorsal angulation. Initial radial length, age and initial dorsal angulation were of importance for the end result of radial length. The strongest linear relationship was found between the end result of radial length and the initial radial length (r = 0.67). This may indicate that the patients who will malunite with radial shortening are those with significant radial axial shortening at the initial presentation. Thus, these patients should be treated with a more stable fixation device.
A 3-dimensional (3D) lower extremity alignment assessment system based on biplanar computed radiography, a camera calibration procedure, and 3D image fitting techniques was developed. The goal of this study was to examine the errors associated with applying this 3D technique to determine component alignment after total knee arthroplasty (TKA). Tibial and femoral component alignment after TKA (varus--valgus, flexion-extension, and internal--external angulations) in 4 patients was determined directly with reconstructions from computed tomography (CT) scans and indirectly with the proposed bone and component image fitting techniques. Mean differences between alignment values from the CT and image fitting techniques ranged from 0.18 degrees to 0.78 degrees, and maximum differences ranged from 0.30 degrees to 0.90 degrees. The proposed 3D method can be reliably used to assess component alignment after TKA.
To compare the alignment after computer-navigated total knee arthroplasty, 52 patients were randomly allocated to 2 groups. Twenty-seven patients received a total knee arthroplasty with the aid of a kinematic computer-navigation system, and 25 patients received a total knee arthroplasty with the conventional method. Both groups were well balanced concerning demographic data and preoperative scores. At 3-month follow-up, the mechanical alignment of the leg reached the desired straight axis in more cases with the computer-navigated implantation. This difference was statistically significant. The femoral and tibial mechanical anteroposterior axis and the femoral and tibial sagittal tilt (slope) measured on sagittal x-rays were not significantly improved in this patient group.
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BACKGROUND: Corrections of combined torsional and angular deformities of long bones may be performed creating a single osteotomy which is oriented so that rotating the two fragments on the created osteotomy plane allows to correct all deformities in one step. A practical geometrical tool is presented to facilitate the difficult preoperative planning of such osteotomies. METHODS: The geometrical tool consists of two limbs connected by a mobile disk representing the osteotomy plane. This allows the two limbs to be deliberately bent and rotated against each other. Thereby, the mobile disk will change orientation in such a way that it will indicate the osteotomy plane needed in order to anatomically align the two limbs. The geometrical principle of the tool has been confirmed mathematically and compared with data from the literature. Five deformed test bones have been used to test the effectiveness of the tool. FINDING: . The geometrical principle of the tool is equivalent with the mathematical data from the literature. The maximal osteotomy angle which can be indicated by the tool is 65 degrees , with an error of +/-3 degrees compared to mathematically calculated values. The five test bones were all aligned anatomically with appropriate accuracy. INTERPRETATION: The presented tool can be easily used and facilitates largely the preoperative planning of a single cut osteotomy for complex deformities of long bones. It allows to avoid sophisticated mathematical calculations and helps to avoid the risk for errors in planning and performing correctional osteotomies.
This article is an introduction to a complex topic on radiographic views as they relate to alignment of the ankle and hindfoot to the lower leg. Patient positioning as it relates to obtaining full-length lower extremity radiograph views are discussed along with contralateral radiographs, which are useful and important for comparative purposes.