A New Classification for the Varus Knee.

BACKGROUND: A new classification for osteoarthritis of the knee associated with varus deformity is presented. This classification is derived from the combination of conventional radiographs, stress radiographs (when needed), and clinical examination. METHODS: This study included the analysis of coronal alignment on full-leg standing radiographs of 526 patients awaiting knee arthroplasty for varus deformity in a single institution. Various mechanical and anatomic angles were measured, and these findings were combined with a basic clinical examination of patients. The radiographs were measured on 2 separate occasions to determine the intraobserver reliability. Cross-sectional studies such as computed tomography or magnetic resonance imaging were used to further refine observations about different wear patterns. RESULTS: Varus deformity can either be intra-articular or extra-articular. Intra-articular deformities can be correctable or fixed. In fixed deformities, the status of the lateral ligament is taken into account. Extra-articular deformity can be metaphyseal or diaphyseal, and the possibility for intra-articular correction will depend on the degree of deformity and its distance from the joint. CONCLUSION: This new classification allows for better definition of varus deformity, which can help surgeons during preoperative planning, particularly with their choice of implant and potentially the degree of constraint. The classification can also be a tool for further prospective studies about varus deformity.

Prevalence of HAGL lesions and associated abnormalities on shoulder MR examination.

OBJECTIVE: Humeral avulsion of the glenohumeral ligament (HAGL) is an uncommon shoulder injury. We report the prevalence of HAGL lesions and other associated shoulder injuries in a large series of shoulder MR examinations. All results were correlated with surgery. MATERIALS AND METHODS: MR reports of 1,000 consecutive conventional shoulder MR exams performed on patients with shoulder pain were reviewed in our information system for the word HAGL. A total of 743 patients went on to surgery. There were 23 HAGL lesions reported at surgery. Those 23 examinations were reviewed retrospectively in consensus by two musculoskeletal radiologists. Scans were assessed for HAGL lesions, full or partial thickness supraspinatus, infraspinatus or subscapularis tendon tears, superior labral anterior posterior (SLAP) tears, anterior or posterior labral tears, and Hill-Sachs lesions. RESULTS: All 23 patients had HAGL lesions at surgery. Sixteen HAGL lesions were seen on prospective MR reading and 17 HAGL lesions were seen on retrospective MR consensus reading. Six HAGL lesions were not seen on retrospective consensus reading. Sixteen patients had Hill-Sachs deformities, ten had subscapularis tendon tears, five had supraspinatus tendon tears, six had superior labral tearing, and six had anterior labral tears. The above findings were confirmed on arthroscopy. CONCLUSIONS: In this series, there was a 1.6 % prevalence on all MR examinations, and prevalence of 2.1 % seen on MR examination for those who went to surgery. Common injuries associated with HAGL lesions are Hill-Sachs deformities and subscapularis tendon tears. Anterior labral tears were seen in only six cases despite Hill-Sachs deformities in 16 patients. In patients with Hill-Sachs deformities without anterior labral tears, one must carefully assess for the presence of a HAGL lesion.

[Lesions of the radio-carpal joint in patients with rheumatoid arthritis and its surgical treatment].

Affection of radio-carpal joint is most frequently revealed in patients, suffering rheumatoid arthritis. While the disease progressing in almost 75% of patients the inflammatory changes in radio-carpal joint occur. An acute and chronic synovitis, damage of a cartilage constitute a cause of a typical erosion of bones inside a joint, weakening of a tendo-ligamentous apparatus and its further deformity. Operative treatment was aimed for the inflammatory focus elimination, reduction of the pain syndrome severity, the function loss, and the joint deformity correction. The mostly used operative interventions are tenoectomy, synovectomy, arthrodesis, total endoprosthesis.

A patient with multifocal tabetic arthropathy: a case report and review of literature.

A 55-year-old man presented with a painless destruction of multiple joints and neurologic deficits. He was admitted with a painless pyogenic arthritis of the right ankle. Four years earlier, he had experienced instability of the right knee after an inexplicable, progressive but painless destruction of the joint. Radiographs showed erosive changes at the smaller joints of both hands and the left foot, as well as deformation and destruction of the right foot. Results from both treponemal and nontreponemal serologic test were positive in blood. The Treponema pallidum particle agglutination index was positive in the cerebrospinal fluid. Tabetic arthropathy was diagnosed.Tabetic arthropathy is a manifestation of neurosyphilis. Because syphilis is known as "the great imitator" and tertiary syphilis is rare, recognizing the disease is the biggest challenge for health care providers. Symptoms may mimic any other disease, and many different medical specialists may be faced with these patients, or as Sir William Osler put it: "He who knows syphilis, knows medicine." Initial diagnosis is usually made on serum and cerebrospinal fluid examination. Penicillin is an effective treatment for neurosyphilis to stop progression of neurologic damage, but it does not cure the previously developed tabetic arthropathy. This case is reported to raise awareness of this uncommon but important manifestation of tertiary syphilis. Unfamiliarity with the clinical presentation of tabetic arthropathy may lead to considerable delay in diagnosis.

Psoriatic arthritis mutilans (PAM) in the Nordic countries: demographics and disease status. The Nordic PAM study.

OBJECTIVE: To determine the prevalence and clinical characteristics of psoriatic arthritis mutilans (PAM) in the Nordic countries. METHOD: Patients with putative PAM aged ≥ 18 years were recruited. Fifty-nine patients were included after clinical examination. RESULTS: The prevalence of PAM in the adult Nordic population was estimated to be 3.69 per million inhabitants [95% confidence interval (CI) 2.75-4.63]. The female to male ratio was close to 1:1. The mean age of skin disease onset was 25 years and the mean age of onset of joint disease was 30 years. The onset of skin disease was 2 years earlier among female patients. At inclusion, the mean duration of arthritis was 27 ± 11 years for male patients and 33 ± 11 years for female patients. PAM was most frequently seen in the distal interphalangeal (DIP) joints of the toes, followed by the IP joint of the thumb and the DIP joint of the little finger on the left hand. Female and male patients had similar numbers of painful and swollen joints. Enthesitis was found in 19 patients (32%), while 38 patients (64%) had a history of dactylitis. Twenty-three of these 38 patients (61%) had a history of dactylitis in the same finger/toe as they had PAM. At the time of inclusion, 45% of the patients were found to have clear or almost clear skin. CONCLUSIONS: PAM in the Nordic countries has a low prevalence, with only three to five cases per million inhabitants. The majority of the patients present with mild skin disease.

Geometry of the proximal humeral articular surface in young children: a study to define normal and analyze the dysplasia due to brachial plexus birth palsy.

BACKGROUND: Little is known regarding the morphology of the proximal humerus in growing children. This study reports bilateral magnetic resonance imaging measurements in children with internal rotation contractures from birth palsy, hypothesizing that dysplasia alters normal humeral sphericity and symmetry. METHODS: We studied 25 children with unilateral internal rotation contractures (mean age, 3.7 years) for humeral shape by bilateral magnetic resonance imaging studies at the mid-glenoid level. Local radii of curvature were compared for symmetry and orientation. RESULTS: Neither side showed uniform radii (sphericity), but normal humeri showed symmetry lost in dysplasia. Internal rotation contractures were correlated with flattening of the anterior humeral head (P = .0002). All heads were flatter in the region of articular contact. The skew axis (the largest cross-sectional diameter of the proximal humerus) was collinear with the articular surface centerline in normal humeri, an alignment often lost with dysplasia, resulting in a skew axis angle. The severity of glenoid deformity correlated with progressive posterior displacement of the humeral head center (P < .0003). CONCLUSION: The normal humeral articular surface in the young child is not spherical and is flatter in the middle than at the periphery but is symmetric about its central axis. Internal rotation contractures result in loss of this symmetry with characteristic flattening of the anterior humeral head and development of a skew axis angle. CLINICAL RELEVANCE: Posterior displacement of the humeral head center of rotation beyond 50% of the calculated head radius warrants vigilance and possibly surgical intervention because there is a high likelihood for development of a pseudoglenoid.

[Forensic medical implications of histomorphological changes in the bone and cartilage tissues under effect of radiation].

The objective of the present work was to study roentgenological, microscopic, and histomorphological changes in the bone and cartilage tissues under effect of different doses of gamma-ray radiation from Gammatron-2 (GUT Co 400) and betatron bremsstrahlung radiation (25 MeV). The total radiation dose varied from 9.6 Gy to 120 Gy per unit area during 5-8 weeks. The study included 210 patients at the age from 7 to 82 years (97 men and 113 women). Histomorphological studies were carried out using samples of bone and cartilage tissues taken from different body regions immediately after irradiation and throughout the follow-up period of up to 4 years 6 months. Control samples were the unexposed bone and cartilage tissues from the same subjects (n = 14). The tissues were stained either with eosin and hematoxylin or by Van Gieson's and Mallory's methods. Gomori's nonspecific staining was used to detect acid and alkaline phosphatase activities. Moreover, argyrophilic substance was identified in the cartilaginous tissue. Best's carmine was used for glycogen staining and Weigert's stain for elastic fibers. Metachromasia was revealed by toluidine blue staining and fat by the sudan III staining technique. In addition, the ultrastructure of cartilaginous tissue was investigated. Taken together, these methods made it possible to identify the signs of radiation-induced damage to the bone and cartilage tissues in conjunction with complications that are likely to develop at different periods after irradiation including such ones as spontaneous fractures, deforming arthrosis and radiation-induced tumours.

Complications of supracondylar osteotomies for cubitus varus.

BACKGROUND: Humeral osteotomies for cubitus varus have a notoriously high complication rate. Pitfalls of this difficult procedure are highlighted. METHODS: A 50-year experience of 68 consecutive surgeries was reviewed. Factors such as surgical approach and fixation technique were compared for complication incidence and type. RESULTS: Seventeen patients (25%) had 23 (34%) clinically remarkable complications. Nine postoperative nerve palsies occurred in 8 patients. Loss of reduction requiring revision or manipulation was seen in 3 patients. The following complications were noted in 2 patients each: nonunion, loss of flexion, lateral prominence, and unsatisfactory scar. Growth arrest, osteomyelitis, and under-correction requiring revision each occurred once. A lateral, triceps-sparing approach was associated with an overall prevalence of complications of 24% (5 of 21) equivalent to the posterior, triceps splitting approach of 24% (10 of 42). An olecranon osteotomy was used in 2 patients both with complications. No nerve injuries occurred in patients who underwent a lateral approach, whereas nerve palsies occurred in 14% (6 of 42) of the patients where a posterior approach was used. An olecranon osteotomy was used in 2 patients with nerve injury occurring in both. A medial approach in 2 patients and a combined medial-lateral approach in 1 patient were used with no complications. Plate and screw fixation was implemented in 29 cases with complications occurring in 6 of them; pin fixation, in 30 cases, 7 of which had complications. There was a higher incidence of under-correction requiring additional surgery with plate fixation (1 of 29) compared with pin fixation which had no under correction but had loss of fixation in 2 of 30. The average correction obtained was similar in the group with complications (32 degrees) versus those without (27 degrees). CONCLUSIONS: Supracondylar humeral osteotomy is a technically demanding procedure fraught with complications. Plate fixation and pin fixation techniques resulted in similar complication rates, but the surgical approach used appeared to make a difference. The posterior, triceps splitting, approach resulted in a high incidence of nerve palsies versus none with the lateral, triceps-sparing approach. LEVEL OF EVIDENCE: This is a retrospective case series, Level IV.

Retrograde dynamic locked nailing for valgus knee correction: a revised technique.

PURPOSE: Traditionally, valgus knee deformity is predominately corrected by stabilisation with a plate inserted via the medial approach to the supracondylar region of the femur. However, this technique is unfavourable from both a biomechanical and a biological point of view. A revised retrograde dynamic locked nailing was developed to improve correction of this defect. METHOD: Forty-one knees with valgus deformity (average tibiofemoral angle, 22°; range, 16-29°) in 25 adult patients were treated by oblique femoral supracondylar varus osteotomy and stabilised with retrograde dynamic locked nails. Postoperatively, early ambulation with protected weight bearing and range of motion knee exercises were encouraged. RESULT: Thirty-five knees of 21 patients were followed-up for an average of 2.6 years (range, 1.1-4.5 years). All osteotomy sites healed with an average union period of 3.4 months (range, 2.5-5.0 months). There were no significant complications. At the latest follow-up, the average tibiofemoral angle was 7.1° valgus (range, 4-10° valgus). For all of the knees, the outcomes were satisfactory (p < 0.001). CONCLUSION: The technique described here may be a feasible alternative for correction of valgus knee deformity. The advantages of this technique include the use of a biomechanically more appropriate method, a minimal complication rate and a high rate of satisfactory outcomes.

Risk factors for medial meniscal pathology on knee MRI in older US adults: a multicentre prospective cohort study.

OBJECTIVES: Meniscal pathology in which the aetiology is often unclear is a frequent finding on knee MRI. This study investigates potential risk factors for medial meniscal lesions or extrusion in middle-aged and elderly persons. METHODS: Prospective cohort study using population-based subjects from Birmingham, Alabama and Iowa City, Iowa, USA (the Multicenter Osteoarthritis Study). 644 men and women aged 50-79 years with or at high risk of knee osteoarthritis (Kellgren and Lawrence grade 0-2) but with normal medial meniscal status at baseline were studied. Paired baseline and 30-month 1.0 T knee MRI were scored for meniscal lesions and extrusion (pathology) and the following systemic, knee-specific and compartment-specific potential risk factors were evaluated: age, sex, body mass index, bony enlargement of finger joints, knee trauma, leg-length inequality and knee alignment. RESULTS: Of 791 knees, 77 (9.7%) had medial meniscal pathology at 30 months follow-up. 61 of the 77 (81%) had no report of trauma during follow-up. Including all potential risk factors in the multivariable model, the adjusted OR for medial meniscal pathology was 4.14 (95% CI 2.06 to 8.31) for knee trauma during follow-up, 1.64 (1.00 to 2.70) for five or more bony enlargements of finger joints (vs ≤ 4) and 2.00 (1.18 to 3.40) for varus alignment (vs not varus) at baseline examination. Obesity was a risk factor for the development of meniscal extrusion, OR 3.04 (1.04 to 8.93) but not for meniscal lesions, OR 1.15 (0.52 to 2.54). CONCLUSIONS: Apart from knee trauma, possible generalised osteoarthritis, expressed as multiple bony enlargements of finger joints, varus alignment and obesity are risk factors for medial meniscal pathology.

Postoperative laxity of the lateral soft tissue is largely negligible in total knee arthroplasty for varus osteoarthritis.

PURPOSE: To evaluate the integrity of lateral soft tissue in varus osteoarthritis knee by comparing the mechanical axis under varus stress during navigation-assisted total knee arthroplasty before and after compensating for a bone defect with the implant. METHODS: Sixty-six knees that underwent total knee arthroplasty were investigated. The mechanical axis of the operated knee was evaluated under manual varus stress immediately after knee exposure and after navigation-assisted implantation. The correlation between each value of the mechanical axis and degree of preoperative varus deformity was compared by regression analysis. RESULTS: The maximum mechanical axis under varus stress immediately after knee exposure increased in proportion to the degree of preoperative varus deformity. Moreover, the maximum mechanical axis under varus stress after implantation increased in proportion to the degree of preoperative varus deformity. Therefore, the severity of varus knee deformity leads to a progressive laxity of the lateral soft tissue. However, regression coefficients after implantation were much smaller than those measured immediately after knee exposure (0.99 vs 0.20). Based on the results of the regression formula, the postoperative laxity of the lateral soft tissue was negligible, provided that an appropriate thickness of the implant was compensated for the bone and cartilage defect in the medial compartment without changing the joint line. CONCLUSION: The severity of varus knee deformity leads to a progressive laxity of the lateral soft tissue. However, even if the degree of preoperative varus deformity is severe, most cases may not require additional procedures to address the residual lateral laxity.

Coracoid abnormalities and their relationship with glenohumeral deformities in children with obstetric brachial plexus injury.

BACKGROUND: Patients with incomplete recovery from obstetric brachial plexus injury (OBPI) usually develop secondary muscle imbalances and bone deformities at the shoulder joint. Considerable efforts have been made to characterize and correct the glenohumeral deformities, and relatively less emphasis has been placed on the more subtle ones, such as those of the coracoid process. The purpose of this retrospective study is to determine the relationship between coracoid abnormalities and glenohumeral deformities in OBPI patients. We hypothesize that coracoscapular angles and distances, as well as coracohumeral distances, diminish with increasing glenohumeral deformity, whereas coracoid overlap will increase. METHODS: 39 patients (age range: 2-13 years, average: 4.7 years), with deformities secondary to OBPI were included in this study. Parameters for quantifying coracoid abnormalities (coracoscapular angle, coracoid overlap, coracohumeral distance, and coracoscapular distance) and shoulder deformities (posterior subluxation and glenoid retroversion) were measured on CT images from these patients before any surgical intervention. Paired Student t-tests and Pearson correlations were used to analyze different parameters. RESULTS: Significant differences between affected and contralateral shoulders were found for all coracoid and shoulder deformity parameters. Percent of humeral head anterior to scapular line (PHHA), glenoid version, coracoscapular angles, and coracoscapular and coracohumeral distances were significantly lower for affected shoulders compared to contralateral ones. Coracoid overlap was significantly higher for affected sides compared to contralateral sides. Significant and positive correlations were found between coracoscapular distances and glenohumeral parameters (PHHA and version), as well as between coracoscapular angles and glenohumeral parameters, for affected shoulders. Moderate and positive correlations existed between coracoid overlap and glenohumeral parameters for affected shoulders. On the contrary, all correlations between the coracoid and glenohumeral parameters for contralateral shoulders were only moderate or relatively low. CONCLUSIONS: These results indicate that the spatial orientation of the coracoid process differs significantly between affected and contralateral shoulders, and it is highly correlated with the glenohumeral deformity. With the progression of glenohumeral deformity, the coracoid process protrudes more caudally and follows the subluxation of the humeral head which may interfere with the success of repositioning the posteriorly subluxed humeral head anteriorly to articulate with the glenoid properly.

The UniSpacer™: correcting varus malalignment in medial gonarthrosis.

While options for operative treatment of leg axis varus malalignment in patients with medial gonarthrosis include several established procedures, such as unicompartmental knee arthroplasty (UKA), total knee arthroplasty (TKA) or high tibial osteotomy (HTO), there has been little focus on a less invasive option introduced more recently: the UniSpacer™ implant, a self-centering, metallic interpositional device for the knee. This study evaluates clinical and radiological results of the UniSpacer™, whether alignment correction can be achieved by UniSpacer™ arthroplasty and alignment change in the first five postoperative years. Anteroposterior long leg stance radiographs of 20 legs were digitally analysed to assess alignment change: two relevant angles and the deviation of the mechanical axis of the leg were analysed before and after surgery. Additionally, the change of the postoperative alignment was determined one and five years postoperatively. Analysing the mechanical tibiofemoral angle, a significant leg axis correction was achieved, with a mean valgus change of 4.7 ± 1.9°; a varus change occurred in the first postoperative year, while there was no significant further change of alignment seen five years after surgery. The UniSpacer™ corrects malalignment in patients with medial gonarthrosis; however, a likely postoperative change in alignment due to implant adaptation to the joint must be considered before implantation. Our results show that good clinical and functional results can be achieved after UniSpacer™ arthroplasty. However, four of 19 knees had to be revised to a TKA or UKA due to persistent pain, which is an unacceptably high revision rate when looking at the alternative treatment options of medial osteoarthritis of the knee.

Wrist deformity, bother and function following wrist fracture in the elderly.

OBJECTIVE: Wrist deformity in older people is common following treatment for a wrist fracture, particularly after non-surgical treatment. A cohort of older wrist fracture patients were surveyed by telephone regarding perceived deformity, bother with deformity and patient-reported wrist function. The objectives were to: (1) determine whether older patients with wrist fractures perceived a deformity of their wrist and if they were bothered by it; (2) test if there were associations between deformity and treatment-type and between deformity and function; (3) test for associations between bother and treatment-type and between bother and function; (4) measure the test-retest reliability of the 'bother' question. RESULTS: Of 98 eligible patients who were invited to participate, 41 responded. Out of 41, 14 (34%) believed they had a deformity and 4 (10%) reported that they were bothered by the appearance of their wrist. Deformity was associated with non-surgical treatment (RR = 3.85, p = 0.006) but was not significantly associated with functional outcomes (p = 0.15). All those who were bothered belonged to the non-surgical treatment group. Bother was significantly associated with poorer functional outcomes (p = 0.006) and this association was clinically significant (MD = 35 points). The deformity and bother questions were found to have excellent test-retest reliability; κ = 1.00 and κ = 0.92, respectively.

Thrombocytopenia absent radius syndrome: presence of brachiocarpalis muscle and its importance.

PURPOSE: Common clinical manifestations associated with thrombocytopenia absent radius (TAR) syndrome have been reported in the literature since its initial description in 1959. The purpose of this study was to report a clinical observation and describe the anatomic location of this brachiocarpalis muscle. METHODS: The radiographs of 20 patients (39 extremities) with TAR syndrome were reviewed and are the focus of this report. The presence or absence of an abnormal muscle crossing both the humero-ulnar and ulno-carpal joint, and its anatomic origin and insertion, were documented by radiographs, surgery, or both. A total of 12 patients underwent surgery on 19 extremities. Furthermore, we compared the radiographs of these 20 patients (39 extremities) with the radiographs of 20 arbitrarily selected patients with non-TAR type IV radial dysplasia, which were part of our database. RESULTS: An abnormal brachiocarpalis muscle was noted radiographically in all 39 of the extremities and was observed surgically in all 19 patients who underwent surgery. It was absent in all 40 extremities of the non-TAR type IV radial dysplasia patients. One TAR patient had only unilateral radial dysplasia. This anomalous muscle has an abnormally high origin on the anterolateral aspect of the proximal humerus, and an insertion into the radial side of the carpus. As such, it has a deforming force at both the wrist and the elbow. CONCLUSIONS: We report the consistent finding of a brachiocarpalis muscle in patients with TAR syndrome. Because of its location, the presence of this muscle may influence the surgical treatment of these patients. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic IV.

The statistical relationship between varus deformity, surgeon's experience, BMI and tourniquet time for computer assisted total knee replacements.

The outcome of total knee arthroplasty (TKA) with severe pre-operative varus deformity is significantly worse than in well aligned knees. Computer navigated TKA has addressed some of the problems by ensuring accurate post-operative alignment. Our aims were to see if navigation could reproducibly correct a varus deformity to 3 degrees of the mechanical axis and to investigate the relationships between the tourniquet time and severity of the preoperative deformity, BMI and a surgeon's experience. The 172 e.motion floating platform TKA's were implanted using the OrthoPilot Navigation system (B Braun-Aesculap, Tuttlingen, Germany). Pre-operative deformity and post-operative alignment were measured by the software. Tourniquet times were recorded automatically. All knees were corrected to within 3 degrees of the neutral axis (mean 0.48 degrees ). Statistically significant relationships between tourniquet time (TT) and degree of pre-operative varus (p<0.001), total number of previous e.motion TKA's performed (p<0.001), and body mass index (p=0.013) were found. A linear relationship between the variables can be expressed as a statistical formula: TT=49.5+PreOp Varus+0.6(BMI)-0.1(total previous). Tourniquet time is measured in minutes and preoperative varus is measured in degrees from the mechanical axis. Total previous is the total number of navigated TKA's implanted by the surgeon. Tourniquet time is increased with larger pre-operative deformities and high BMI and decreased with surgical experience. The formula may give us a method of predicting the length of a procedure for a particular surgical team and may allow us to plan operating lists more accurately.

A comparison of coronal plane axial femoral relationships in Asian patients with varus osteoarthritic knees and healthy knees.

Standing full-length radiographs were measured to compare coronal femoral axes between 250 limbs in patients with varus osteoarthritis with 50 healthy controls. Mean distal femoral axis-mechanical axis angle was 7.3 degrees +/- 1.6 degrees , and mean femoral bow was 3.6 degrees +/- 2.5 degrees in patients compared to 5.5 degrees +/- 0.8 degrees and 0.4 degrees +/- 1.2 degrees , respectively, in controls. Femoral condylar-mechanical axis angle was significantly lower in osteoarthritic limbs (89.9 degrees + 2.8 degrees ) as compared to controls (93.1 degrees + 1.6 degrees ). Varus deformity correlated significantly with femoral bowing (P < .05; correlation coefficient, 0.4). Osteoarthritic limbs (18.8%) showed a distal femoral axis-mechanical axis angle more than 9 degrees . These findings have implications in deciding the optimum valgus angle at which to perform distal femoral resection in total knee arthroplasty.

Total knee replacement in the fixed valgus deformity using a lateral approach: role of the automatic iliotibial band release for a successful balancing.

The purpose of this work was to document eleven years of experience in knee replacement for fixed knee valgus through a lateral approach with special emphasis on the balancing procedures. At a mean follow-up of seven years, only one revision for sepsis was required in this series of 63 knee replacements. The mean knee score improved from 37 (range 20-45) to 91 (range 65-100) at the last review (p < 0.01) while the function score increased from 29.5 (range 0-50) to 78.7 (range 10-100) (p = 0.01). The mean mechanical axis (HKA) was 14.7 degrees of valgus preoperatively and 1 degrees of valgus postoperatively. After the iliotibial band was automatically released in the approach, only four of 63 knees required additional release for tightness in extension. These results underline the appeal of the lateral approach with the automatic release of the iliotibial band. If required, additional ligament release is recommended step-by-step after bone section to avoid postoperative instability.

[Alternative method for measuring the mechanical axis of the knee]. / Método alterno para medición del eje mecánico de rodillas.

OBJECTIVE: To identify the existence of significant differences in the degrees of mal-alignment of the mechanical axis of the knee between a traditional measuring method and an alternative method. MATERIALS AND METHODS. One hundred mechanical axes of the knee were determined in patients of both sexes. The degree of axis mal-alignment was obtained first using the traditional measuring method and subsequently using the alternative method. The results obtained from the two methods were then compared. The measurement variable control was standardised by positioning the patients in the same place during radiography when beginning mechanical axis determination. A wooden ruler on which each centimetre was indicated by a metal strip and numbered at every 10-centimeter interval was used to evaluate the degree of pelvic mal-alignment. The ruler was then used as a mechanical axis correction reference in accordance with the characteristics of each patient. RESULTS: The following results were obtained from 100 mechanical axes evaluated by the traditional method and by the alternative method, respectively: varus deformity of the right pelvic segment was 21 degrees +/- 16 degreesuv. 7 ++/-6. degrees varus deformity of the left pelvic segment was 22 _+/-170 degreesvs. 8 ++/-50 degrees valgus deformity of the right pelvic segment was 21 - /-150 degreess. 8 + +/-; and valgus deformity of the left pelvic segment was 16 +/- 11 vs. 6 +/- 5 degrees. CONCLUSIONS: Our results suggest that the proposed method provides more accurate mechanical axis measurement and that the correction is exponential: the greater the angle measured traditionally, the greater the correction with our proposed method.

Recurrence of varus/valgus deformity after TKR at 3 years' follow-up.

We assessed 30 patients with a cemented TKR implant (Interax ISA, Stryker Orthopaedics) at 1 and 3 years follow-up. We wanted to ascertain whether knee alignment was maintained during the critical period of follow-up in meniscal-bearing PCL-retaining TKR patients and test if correlations exist between alignment variations in the coronal plane and preoperative varus/valgus deformity or tibial component position and migration with respect to the tibia. Lower limb alignment was evaluated by measuring the angle between the tibia and femur anatomical axis directly from the antero-posterior radiographs and the tibial component position with respect to the tibial anatomical axis. The tibial component varus/valgus migration in the tibia was measured by roentgen stereophotogrammetric analysis. The results showed that at 3 years follow-up 40% of patients presented an alignment variation of over 3 degrees . The recurrent deformity was not correlated with the preoperative deformity, nor with the tibial component position with respect to the tibial shaft nor with its migration. After total knee arthroplasty coronal axial variation is a common finding and it depends on the overall limb muscles and ligaments adaptation to prosthetic constraints.