Epicondylar Line Research Articles

Determination of Standard Values for Knee Version in a Healthy Population

Background: Different measures are used to describe relevant anatomic variations that can result in patellofemoral instability and disorders. Knee version, the relative rotational alignment between the femur and tibia in the axial plane at the level of the knee, may have a decisive effect on the kinematics of the patellofemoral joint. However, data regarding the values of knee version are currently lacking. Purpose: This study aimed to determine standard values for knee version in a healthy population. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 100 healthy volunteers (50 male and 50 female) without patellofemoral disorders or lower extremity malalignment were included in this study and underwent knee magnetic resonance imaging. The torsion values of the femur and tibia were independently measured using the Waidelich and Strecker method. Knee version, defined as static rotation of the tibia with respect to the femur in full extension, was determined by measuring the angle between the tangent lines to the dorsal femoral condyle (DFC) and the dorsal tibial head (DTH; defined by the posterior point of the proximal tibial plateau). Supplementary measurements were obtained as follows: (1) femoral epicondylar line (FEL), (2) tibial ellipse center line (TECL), (3) tibial tuberosity–trochlear groove (TT-TG) distance, and (4) tibial tuberosity–posterior cruciate ligament (TT-PCL) distance. Results: In 200 analyzed legs of 100 volunteers (mean age, 26.5 ± 5.8 years [range, 18 to 40 years]), we identified a mean internal femoral torsion of −23.8°± 9.7° (range, −46.2° to 1.6°), external tibial torsion of 33.2°± 7.4° (range, 16.4° to 50.3°), and external knee version (DFC to DTH) of 1.3°± 3.9° (range, −8.7° to 11.7°). Other measurements were as follows: FEL to TECL, −0.9°± 4.9° (range, −16.8° to 12.1°); FEL to DTH, −3.6°± 4.0° (range, −12.6° to 6.8°); and DFC to TECL, 4.0°± 4.9° (range, −12.7° to 14.7°). The mean TT-TG distance was 13.4 ± 3.7 mm (range, 5.3-23.5 mm), and the mean TT-PCL distance was 11.5 ± 3.5 mm (range, 6.0-20.9 mm). Female participants had significantly greater external knee version than male participants. Conclusion: Coronal- and sagittal-plane alignments of the knee have a well-known effect on the biomechanics of this joint. Additional information about the axial plane may result in new decision-making algorithms for managing knee disorders. This study is the first to report standard values of knee version in a healthy population. As a subsequent step building on this work, we advocate for the measurement of knee version in patients with patellofemoral disorders, as this parameter may assist with new treatment guidelines in the future.

Variations in the Terminal Branches of Brachial Artery- A Cadaveric Cross-sectional Study

Introduction: Brachial Artery (BA) begins as a continuation of axillary artery at the distal border of teres major, it appears in the cubital fossa, where it ends at the level of the neck of radius by dividing into radial and ulnar arteries. Common Interosseous Artery (CIA) is the largest branch of Ulnar Artery (UA) and arises in the cubital fossa. The terminal branches of BA at elbow are clinically important since they are responsible for the arterial supply to the forearm and hand. These arteries may get damaged during fractures of the elbow. Aim: To know the variations in the terminal branches of the BA at elbow. Materials and Methods: The present cross-sectional cadaveric study was done on 40 upper limbs from embalmed adult human cadavers in the Department of Anatomy, Kamineni Institute of Medical Sciences, Narketpally, Telangana, India, from August 2017 to August 2019. Dissection of BA in arm and cubital fossa was carried out according to Cunningham’s manual of practical anatomy. The distance of division of BA into radial and UA and distance of origin of CIA from Inter Epicondylar Line (IEL) of humerus were noted. Results: In present study, 20 right-side specimens and 20 left- side specimens were obtained. Among 20 cadavers used, 16 were male cadavers and four were female cadavers. The mean distance (D1) of normal division of BA into the Radial Artery (RA) and UA at elbow was 2.8 cm below the imaginary line joining the medial and IEL. The mean distance (D2) of normal origin of CIA was 6.8 cm below the imaginary line joining the medial and lateral epicondyles of the humerus (IEL). CIA arising from the UA was present in 37 specimens (92.5%) and in the rest three specimens Anterior Interosseous Artery (AIA) and Posterior Interosseous Artery (PIA) arose directly from the UA. Conclusion: The present study has found variations in site of division of terminal branches of the BA at elbow in three specimens

Safe Arthroscopic Approaches for Epicodilitis: Topographic-Anatomical Study

Background. Arthroscopic methods of diagnosis and treatment of elbow diseases have not yet become widespread due to the small volume of the joint, the close location to neurovascular bundles and the manipulation difficulty.
 The aim of the study was to determine the safe zones for the minimally invasive approaches to the elbow in patients with lateral and medial epicondylitis.
 Methods. A complex anatomical and clinical study was performed. The anatomical part was carried out on 30 non-fixed anatomical preparations of the upper limb. The features of the tendon-muscular and neurovascular structures surrounding the elbow were studied, depending on the angle of elbow flexion at three different levels: level I 5 cm above the articular gap, level II the articular gap, level III the neck of the radius. In the clinical part of the study, the these structures were studied by MRI in 30 patients.
 Results. The brachial artery at the level I is located from the bone at a distance 28.6 (28.4-28.7) mm at the elbow flexion to 90. The radial nerve at level II is located at a distance of 15.8 (15.6-16.0) mm from the nominal medial epicondylar line (NMEL). From the NMEL the median nerve is located at a distance of 17.5 (16.6-18.1) mm, the brachial artery 22.4 (20.5-22.8) mm. The anterior bundle of the medial collateral ligament has the following average width throughout: the proximal part 6.21.4 mm; the middle part 6.51.5 mm; the distal part 9.31.4 mm. The average area of the medial collateral ligament attachment to the medial condyle of the humerus was 45.59.3 mm2 and has a rounded shape. The average length of the radial collateral ligament was 20.51.9 mm; width 5.20.8 mm, the average area of its attachment to the humerus was 13.61.4 mm2. The average area of the extensor carpi radialis brevis on the lateral condyle of the humerus was 53.13.7 mm2. The average distance from the entrance of the deep branch of the radial nerve into the supinator canal to the articular gap 28 (25.5-29.6) mm.
 Conclusion. The results of the study make it possible to choose the safe arthroscopic approaches to the elbow with minimal risk of damage to neurovascular structures in the treatment of patients with lateral and medial epicondylitis.

Anatomical study of the anterior interosseous nerve.

The aim of this study is to investigate the location of nerves that innervate the flexor digitorum profundus (FDP), the flexor pollicis longus (FPL) and the pronator quadratus muscles. It also investigates the change in nerve location with hand movement. We studied 30 adult cadavers (17 males and 13 females) with a mean age of 69.5 years (range: 60-95 years). The reference line was from the humeral epicondylar line to the styloid process line of both the radius and ulnar bones. This study measured the anterior interosseous nerve (AIN) branch outpoint and the innervated muscle nerve entry point to the muscle belly. It also examines nerve position changes as related to making a fist. The reference line mean distance was 24.1 ± 1.2 cm. The median nerve branched into the AIN at 18.0 ± 4.0%. We found the most densely distributed section of the nerves' entry point to the muscle belly to be at a distance of 30% to 40% for the FDP and from 30% to 40% for the FPL. Except for the FPL, the nerve branch outpoints and the FDP moved by 3.0%, depending upon hand movements. The results of this study show that it will be necessary to consider the anatomy of the nerve location as it enters the muscle belly as well as how it changes with movement.

Ultrasonographic anatomy of posterior antebrachial cutaneous nerve in healthy subjects.

The posterior antebrachial cutaneous nerve (PACN) is one of the cutaneous branches of the radial nerve, and receives sensory input from the posterior arm and forearm. The aim of this study is to describe the ultrasonographic anatomy of the PACN. PACN and its branches were scanned using ultrasonography in 30 healthy volunteers. The distances between the epicondylar line and the bifurcation site of each branch of PACN (A) point of separation of the radial nerve and the PACN, (B) point of separation of the anterior and posterior divisions, (C) point of bifurcation of the posterior division into the epicondylar and anconeus branches), cross-sectional areas and depths from the skin surface to each nerve at positions A, B, and C were measured. The mean distance from the epicondylar line to A, B, and C was 10.01 ± 0.82 cm, 7.46 ± 0.98 cm, and 4.02 ± 1.16 cm, respectively. The mean depth from the skin surface at A, B, and C was 1.00 ± 0.19 cm, 0.72 ± 0.19 cm, and 0.51 ± 0.12 cm, respectively. Ultrasonographic visualization of the PACN and its major branches was feasible. The reference values in this study may be helpful for more accurate sonographic assessment and electrophysiologic study, and contribute to safer interventions around the elbow region.

English

BACKGROUND Arcade of Frohse (AF) is a tendinous superior margin of superficial layer of supinator muscle which was first described by Frohse and Frankel in 1908. Since then it has been studied by many authors and held accountable as one of the essential components for compression of deep branch of radial nerve (DBRN) which leads to radial tunnel syndrome. Considering AF as an important element of compression, we made an attempt to classify it on the basis of its shape and to find out if any particular shape has a predominant role in compression of the nerve. We also observed the structure of superior and inferior margin of the supinator muscle. METHODS This study was conducted among 80 (70 males and 10 females) formalin fixed upper limbs present in the Department of Anatomy. The limbs were maintained in supine with slightly flexed position and dissection was performed to expose the supinator muscle. The proximal and distal borders of supinator muscles were examined meticulously with the help of magnified lens. The morphometric measurements were taken with the help of a digital caliper. RESULTS The FA is classified into four categories as loop, high arc, low arch and linear shaped. The most frequent shape observed was arch shaped (high and low arch) about 66%, followed by loop shaped (30%) and least was linear shaped (2.5%). On the basis of structure, the proximal and distal margin of supinator muscle was reported to be tendinous in majority of the cases. The distance of the AF from the fixed reproducible anatomical landmark like inter epicondylar line (IEL) was measured and the average distance found was 3.36 cm. CONCLUSIONS Knowledge of different shapes would aid surgeons and radiologists for better approach towards diagnosis and management of supinator syndrome. The morphometric finding can be useful for surgeons to locate the superior margin of supinator (AF) in surgical procedures for decompression of DBRN in supinator syndrome. KEY WORDS Arcade of Frohse, Inter Epicondylar Line, Supinator Muscle, Deep Branch of Radial Nerve and Radial Tunnel Syndrome

Press-fit reverse shoulder arthroplasty in case of advanced humeral bone loss – Is additional distal fixation necessary for primary stability?

BackgroundRevision reverse shoulder arthroplasty (RSA) poses considerable surgical challenges. We hypothesized that a newly developed press-fit stem, which is modeled on the medullary canal of the supracondylar region of the distal humerus by a slight distal bend, achieve both correct fit and sufficient primary stability and that additional distal fixation by interlocking screws is favorable in case of advanced humeral bone loss. MethodsA modular tapered press-fit stem was implanted in 16 Sawbone humeri in three consecutively created defect situations (200 mm (experimental group type 3°), 160 mm (type 4°) and 120 mm (type 5°) bone length above the epicondylar line. In experimental groups type 4° and 5°, additional distal interlocking screw fixation with one to three screws was tested. Primary stability was investigated by measuring micromotions with a high-precision rotational setup. FindingsHighest relative micromotions were noted at the proximal end in experimental groups type 3° and type 4°, whereas in type 5° highest micromotions could be seen at the distal end. Overall micromotions were significantly lower in type 3° and increased with extended defect size. In experimental group type 5°, micromotions increased with reduced additional distal screw fixation. InterpretationThe examined press-fit stem did not provide sufficient primary rotational stability in all constructs without additional support. Advanced distal humeral bone loss had a strong impact on primary fixation. In experimental group type 5° with 120 mm bone remaining, it might be beneficial to use three distal interlocking screws in the supracondylar region in order to neutralize torque and to avoid early loosening.

Correlation between the femoral trochlear line -- epicondylar line angle and intercondylar notch width index in an Iranian population

Objectives: Distal femur anthropometric indices are the main parameters for the design of knee implants. However, there are several variations concerning the anatomy and congruence of the distal femur in different populations. The purpose of this study was to identify anthropometric data on the distal femur and investigate the correlation between the trochlear line – epicondylar line angle and intercondylar notch width index in an Iranian population. Methods: Distal femur measurements were performed in 158 knees on bony specimens and 187 MRIs from an Iranian population. Intercondylar width, intercondylar notch width, and trochlear line – epicondylar line angle were measured and intercondylar notch width index was calculated. Results: In bony specimens, the trochlear line – epicondylar line angle was measured as 7.38° and intercondylar notch width as 19.36 mm. In MRI images, the trochlear line – epicondylar line angle was measured as 6.07° and notch width index as 0.276 mm. Linear regression analysis showed a significant relationship between the trochlear line – epicondylar line angle and notch width index (p<0.05). Conclusion: The results of this study provide fundamental data for the design of knee prostheses suitable for the Iranian population.

Tracking Anatomical Variation of the Bifurcation of the Radial Nerve: Clinical Implication for Physicians

Regional nerve blocks of the upper limb are usually performed in the brachial plexus, specifically in the supra- or infra-clavicular or axillary nerve regions, in cases where minor surgical procedures are required in the distal portion of the extremity. These approaches may not be optimal due to the close proximity of major vascular structures to the needle entry site. This quantitative study measured the site of the radial nerve bifurcation using calipers and ultrasound (US) to determine whether minor surgical procedures (i.e., wound exploration, laceration repair and distal radius reduction) could rely on nerve blocks within a single nerve distribution, in a defined region of the cubital fossa. A metal cylinder was aligned along the medial and lateral epicondyles of 59 donor body arms. A digital caliper, perpendicular to the cylinder, allowed for measurement above (+) or below (-) the epicondylar line (0mm). The average bifurcation occurred at -13.84mm, with 85% of bifurcations arising in the forearm below 0mm. US digital data from a cross-sectional sample of live patients were included in our analysis. US guided needle nerve blocks are presently used by physicians for cases involving injury distal to the elbow. Our results indicate that it is possible to establish “safe zone” parameters in regional nerve blocks to maximize functional recovery while minimizing collateral vascular damage.

Improved tibial component rotation in TKA using patient-specific instrumentation.

Patient-specific instrumentation (PSI) was introduced in an attempt to reduce positional outliers of components in total knee arthroplasty (TKA). It was hypothesized that PSI could help with the positioning of tibial components in optimal rotational alignment. A magnetic resonance imaging (MRI) analysis of 58 patients following TKA was conducted. Of these, 30 operations were performed using PSI and 28 using conventional instrumentation. The rotation of the tibial components was determined in MRI using three different reference lines: a tangent to the dorsal tibial condyles, the tibial epicondylar line, and the tibial tubercle. Deviations >9° were considered outliers. Also internal rotation >1° was considered an outlier. Data were analyzed statistically for positional outliers using the Chi-squared test. There was excellent inter- and intraobserver reliability with low standard deviations for the determination of tibial component rotation using the tangent to the dorsal condyles and the tibial epicondylar line as reference. Using the dorsal tangent as reference, there were eight components in excessive external rotation (28.6 %) and one component being in relative internal rotation (5.4°) in the conventional group, while there were two components in excessive external rotation in the PSI group (6.7 %). Using the tibial epicondyles as reference, there were seven components in excessive external rotation (21.4 %) and one component being in relative internal rotation (4.4°) in the conventional group; while there were two components in excessive external rotation in the PSI group (6.7 %). These differences were statistically significant (p < 0.05). Measurements based on the tibial tubercle showed poor reproducibility in terms of intra- and interobserver reliability and was of little use in the context of the research question. In this setup, PSI was effective in significantly reducing outliers of optimal rotational tibial component alignment during TKA. Anatomy of the proximal tibia does not deliver clear landmarks that are prominent and consistent. This makes both, MRI analysis as well as cutting jig production and intraoperative placement a challenge.

Median ulnar nerves communication in the forearm: a study with autopsy material.

The incidence of median-ulnar communication in the forearm presents variability in different population groups. The aim of this study was to determine the incidence and morphologic expression of the median-ulnar communication in a sample of the Colombian population. One hundred and eight forearms of autopsy material at the National Institute of Forensic Medicine of Bucaramanga, Colombia were studied. Using an approach of the flexor compartment of forearm the median and ulnar nerves were dissected and the communications between these two structures were characterized. The communicating branch occurred in 28 (25.9%) forearms. It occurred unilaterally in 12 specimens and bilaterally in 8, with statistically significant difference (P=0.01). The communication between the anterior interosseous and ulnar nerves was most frequent, observed in 13 (46.4%) forearms. The length of the communicating branch was 56.9 +/- 8.3 mm. The distance of the proximal and distal points of the communicating branch to the bi- epicondylar line was 59.6 +/- 15.4 mm and 102.7 +/- 23.5 mm respectively. The length of the forearm was 269.8 +/- 15.9 mm. A projection of the communicating branch from the upper third to the midthird of the forearm was observed. The incidence of the median-ulnar communication in the present study is in the high rank reported in the literature; there is an agreement with prior studies in finding more numerous communicating branches in the right forearm. The median-ulnar communication should be taken into account for surgical approach of the forearm.

Computer-Assisted Navigation in Patellofemoral Arthroplasty: a New Technique to Improve Rotational Position of the Trochlea

Maltracking or subluxation is one of the complications of patellofemoral arthroplasty. We questioned whether the computed navigation system can improve patellar tracking in patients with patellofemoral arthroplasty (PFA). Between 2007 and 2010 we performed 15 patellofemoral arthroplasties using the Ceraver PFA and navigation assistance. Fifteen other patients underwent surgery without navigation during the same period and acted as a control group. The rotation of the native trochlea as measured using the epicondylar line as a reference before surgery and the rotation of the trochlear component and the trochlear twist angle were assessed with computed tomography (CT) scan after surgery. The mean follow-up was 3years (range, 2-5years). The group with navigation had no patellofemoral complications and better clinical scores. The group without navigation had abnormal patellofemoral tracking in 5 of the 15 patients. CT scan demonstrated excessive internal component rotation, as compared with patients without complications. This excessive internal rotation was proportional to the severity of the patellofemoral maltracking. The short-term results suggest that navigation can lead to better trochlear rotation which, in our hands, is associated with fewer cases of patellar maltracking and better overall clinical scores.

単純X線画像を用いた変形性膝関節症における関節裂隙狭小化の定量的解析

Conventional radiography is first performed in the evaluation of knee osteoarthritis (OA). In view of diagnostic accuracy and reproducibility, joint space narrowing that is a typical feature of knee OA should be evaluated quantitatively based on the image findings, because it has been evaluating subjectively. We measured joint space widths and joint space areas on knee radiographs to analyze joint space narrowing quantitatively and investigated the usefulness in classification of the severity of knee OA. Radiographs of 35 no OA knees (normal group) and 46 OA knees (OA group) were analyzed in this study. Medial and lateral joint space width and joint space area were measured manually using ImageJ i.e., a public domain image processing program. Measured values were corrected for the physical size with the length of epicondylar line, and statistically significant differences between the normal group and OA group were investigated. The results showed that medial joint space width was significantly smaller and lateral joint space width was significantly larger in the OA group than in the normal group. Furthermore, joint space area in the OA group decreased significantly compared that in normal group. We conclude that joint space widths and joint space area are important parameters to classify the severity of knee OA.

Die sagittale Gleitosteotomie des lateralen Kondylus nach Briard beim Oberflächenersatz des kontrakten Valgusknies

Distalization of the insertion of the lateral collateral ligament and popliteus tendon by sliding osteotomy of the lateral femur condyle in order to correct a residual contracture in extension in total knee arthroplasty (TKA) of the severe valgus deformity. Genuine and other valgus deformity of the knee. Severe laxity of the medial collateral ligament; common contraindications of joint replacement. Lateral parapatellar approach and stepwise osteotomy of the tubercle of the tibia, subperiostal release of the lateral contracted structures such as iliotibial band (ITB) and lateral collateral ligament (LCL) in flexion. Tibia first technique, verification of a balanced and stable flexion gap parallel to the epicondylar line. Posterior cruciate ligament (PCL) is preserved. Referencing of the distal femoral cut by a spacer filled only in the medial extension gap. Finishing femoral chamfer cuts. If extension gap remains trapezoidal, further release of the residual lateral contracted structures in extension by means of sliding osteotomy of the lateral condyle and subperiostal release of the capsule and the lateral septum intermusculare is required. Termporary fixation of the lateral condyle by K-wires, resection of the bony excess, trial of test components, definite screw fixation. Comparable to TKA in varus deformities by a medioparapatellar approach. A total of 79patients (61 women, 18 men, average age 71years at the time of surgery) with fixed valgus deformities were operated between June 2001 and December2010 using TKA and sliding osteotomy of the lateral femoral condyle. The preoperative valgus angle under defined valgus and varus stress was 19.5° (8-40), postoperative 4.7° (2-11). Mean medial angle (valgus stress) of the follow-up was 2.1° (0.5-5°), lateral angle (varus stress) 2.3° (0.5-5°). A total of 35patients were followed-up, at a mean of 73.3month (24-109months). The postoperative Knee Society Score was 95 points (56-100points), while the postoperative Function Score was 90 points (55-100points) postoperatively. The Oxford Score improved from 22points (3-43points) preoperatively to 45 points (21-48points) postoperatively. One knee had to be revised due to infection, one knee due to non-union of the tibial tubercle. Finally, there were 3cases with complications associated with the procedure due to the sliding osteotomy of the lateral femoral condyle; all were revised successfully. No conversion to a semi-constrained or constrained knee prosthesis was necessary.

Anatomical Study of the Radius and Center of Curvature of the Distal Femoral Condyle

In this anatomical study, the anteroposterior curvature of the surface of 16 cadaveric distal femurs was examined in terms of radii and center point. Those two parameters attract high interest due to their significance for total knee arthroplasty. Basically, two different conclusions have been drawn in foregoing studies: (1) The curvature shows a constant radius and (2) the curvature shows a variable radius. The investigations were based on a new method combining three-dimensional laser-scanning and planar geometrical analyses. This method is aimed at providing high accuracy and high local resolution. The high-precision laser scanning enables the exact reproduction of the distal femurs-including their cartilage tissue-as a three-dimensional computer model. The surface curvature was investigated on intersection planes that were oriented perpendicularly to the surgical epicondylar line. Three planes were placed at the central part of each condyle. The intersection of either plane with the femur model was approximated with the help of a b-spline, yielding three b-splines on each condyle. The radii and center points of the circles, approximating the local curvature of the b-splines, were then evaluated. The results from all three b-splines were averaged in order to increase the reliability of the method. The results show the variation in the surface curvatures of the investigated samples of condyles. These variations are expressed in the pattern of the center points and the radii of the curvatures. The standard deviations of the radii for a 90 deg arc on the posterior condyle range from 0.6 mm up to 5.1 mm, with an average of 2.4 mm laterally and 2.2 mm medially. No correlation was found between the curvature of the lateral and medial condyles. Within the range of the investigated 16 samples, the conclusion can be drawn that the condyle surface curvature is not constant and different for all specimens when viewed along the surgical epicondylar axis. For the portion of the condylar surface that articulates with the tibia during knee flexion-extension, the determined center points approximate the location of the centers of rotation. The results suggest that the concept of a fixed flexion-extension axis is not applicable for every specimen.

Transepicondylar axis accuracy in computer assisted knee surgery: A comparison of the CT-based measured axis versus the CAS-determined axis

Rotational malalignment is recognized as one of the major reasons for knee pain after total knee arthroplasty (TKA). Although Computer Assisted Orthopaedic Surgery (CAOS) systems have been developed to enable more accurate and consistent alignment of implants, it is still unknown whether they significantly improve the accuracy of femoral rotational alignment as compared to conventional techniques.We evaluated the accuracy of the intraoperatively determined transepicondylar axis (TEA) with that obtained from postoperative CT-based measurement in 20 navigated TKA procedures. The intraoperatively determined axis was marked with tantalum (RSA) markers. Two observers measured the posterior condylar angle (PCA) on postoperative CT scans.The PCA measured using the intraoperatively determined axis showed an inter-observer correlation of 0.93. The intra-observer correlation, 0.96, was slightly better than when using the CT-based angle. The PCA had a range of −6° (internal rotation) to 8° (external rotation) with a mean of 3.6° for observer 1 (SD = 4.02°) and 2.8° for observer 2 (SD = 3.42°). The maximum difference between the two observers was 4°. All knees had a patellar component inserted with good patellar tracking and no anterior knee pain. The mean postoperative flexion was 113° (SD = 12.9°). The mean difference between the two epicondylar line angles was 3.1° (SD = 5.37°), with the CT-based PCA being larger.During CT-free navigation in TKA, a systematic error of 3° arose when determining the TEA. It is emphasized that the intraoperative epicondylar axis is different from the actual CT-based epicondylar axis.

Complication rate, outcome, and risk factors associated with surgical repair of fractures of the lateral aspect of the humeral condyle in dogs

To determine outcome, report complications, and risk factors for complications associated with the surgical treatment of fractures of the lateral aspect of the humeral condyle (FLHC) in dogs. Fifty dogs with FLHC that had been repaired surgically were included in this retrospective case series. The medical records and radiographs from 50 dogs with FLHC from 1990--2006 were analyzed. The complication rate was 30%. For every 30-minute increase in surgical time the odds of a complication increased by 2.00 (95% CI: 1.06, 3.77). For every 10 degrees increase in the angle between the transcondylar screw and a line between the epicondyles viewed on a craniocaudal radiograph there was a 4.82 (95% CI: 1.23, 18.86) greater odds of an intracondylar fracture gap appearing on postoperative radiographs. When an intracondylar fracture gap was present after surgery there was a 25% long-term radiographic outcome failure rate, whereas there was a 0% radiographic failure rate in the dogs in which an intracondylar fracture gap was not present. In conclusion, transcondylar screw placement parallel to the epicondylar line should be attempted for the repair of FLHC. An increase in surgical time leads to an increase in postoperative complication rate. The presence of an intracondylar fracture gap may be associated with fracture failure. Screw angulation predisposed to postoperative intracondylar fracture gap which in turn may be associated with higher fracture fixation failure rate. The dogs that had prolonged surgical times had an increased complication rate.

Medial torsion of the tibia in Japanese patients with osteoarthritis of the knee.

To assess the reliability of the landmarks for the rotationally neutral alignment of the tibial component in total knee arthroplasty for Japanese patients, the rotational position of the medial (1/3) of the tibial tuberosity relative to the femoral epicondylar line (Angle TT) and that relative to the center of the ankle (Angle TT-AA) were measured in 24 knees with medial femorotibial osteoarthritis and in 28 normal knees by computed tomography. Angle TT-AA shows the degree of medial torsion of the tibia. The range of Angle TT and that of Angle TT-AA each was greater than 40 degrees. The position of the tibial tuberosity and degree of medial torsion of the tibia varied by individual. In patients with severe medial torsion, the internal rotation of the foot is extreme if the medial (1/3) of the tibial tuberosity is used for the rotationally neutral alignment of the partially constrained tibial component. In the treatment specifically of patients from East Asian countries, medial torsion of the tibia should be taken into account in total knee arthroplasty to ensure proper patellar tracking and proper rotation of the foot in knees with medial femorotibial osteoarthritis.

The alignment of components in total hiparthroplasty

The alignment of components is one of the most important topics in total knee arthroplasty. The resections should be performed according to anatomical landmarks, such as the epicondylar line, the anterior-posterior axis and the tibial tubercle. Some important anatomical properties of the human knee joint and their significance for surgical technique are described.

ＭＲＩを用いた膝蓋けんの位置の評価法

In knee with patellofemoral disorder, MRI was taken both at full extension and at 30° of knee flexion. Images at the level of the femoral epicondyle and at the level of tibial articular surface were superimposed, and three parameters were measured to analyze the rotational and anteroposterior positions of the patellar tendon.First, the trans-epicondylar line was drawn and the central point was defined as Point C. The angle between the line (Line PT) from the central point of the patellar tendon to Point C and the epicondylar line was defined as Angle PT. The angle between the line from the most anterior point of the lateral condyle to Point C and Line PT was defined as Angle LC-PT. Next, a circle was drawn so that the trans-epicondylar line was the diameter of the circle. The ratio of the distance PT relative to the length of the radius of the circle was defined Ratio PT. Angle PT and Angle LC-PT demonstrate rotational angle of the patellar tendon relative to the epicondylar line. Ratio PT demonstrates anteroposteior position of the patellar tendon.In case of excessive lateral pressure syndrome, the patellar tendon located postero-laterally at 30° of flexion compared to the normal knees. In one case of patellofemoral arthritis, the patellar tendon located antero-laterally at 30°of flexion. This technique was usuful in the analysis of the mechanism of the patellofemoral disorder.