The weight bearing axis of the limb goes from the pelvis to the ground and includes the hindfoot. However, the influence of hindfoot alignment on mechanical axis deviation and overall limb alignment after total knee arthroplasty (TKA) is unknown. This study aimed to assess the change in hindfoot alignment after TKA for knee osteoarthritis, the difference in mechanical axis deviation at the knee when calculated using the ground mechanical axis as compared to the conventional mechanical axis, and the effect of hindfoot alignment on the overall postoperative limb alignment after TKA. We evaluated the pre- and postoperative hip-knee-ankle (HKA) angle, conventional mechanical axis deviation (CMAD), ground mechanical axis deviation (GMAD), and tibiocalcaneal angle (TCA) in 125 patients who underwent 165 consecutive TKAs. Overall, the change in pre- and postoperative mean TCA was not significant (p=0.48) whereas it was significant (p=0.01) in knees with =15° deformity where the hindfoot valgus decreased by approximately 25%. Preoperatively, there was no significant difference between mean CMAD and mean GMAD whereas postoperatively the difference was significant (p=0.0001). Hindfoot valgus alignment of =10° was present in 22.5% of limbs and 29% limbs had a postoperative GMAD of =10 mm in spite of the limb alignment being restored to within 3° of neutral after TKA. Despite accurate restoration of limb alignment after TKA, as a result of persistent hindfoot valgus alignment the ground mechanical axis may pass lateral to the centre of the knee joint - with potential detrimental effects on bone, ligaments and implants

Introduction. Intramedullary lengthening devices have been in use in older children with closed /open growth plates with good success. This study aims to present the early experience of the FITBONE nail since withdrawal of the PRECICE nail. Materials & Methods. Retrospective analysis of both antegrade and retrograde techniques were utilized. Only patients where union was achieved and full weight bearing commenced were included. The complication rate, length gained, distraction index, weight bearing index (WBI) as well as mechanical axes were analysed. Results. 14 (7 males, 7 females) of a total of 16 (7 males, 7 females) patients with a mean age of 16.9 years with varied diagnosis of LLD were analysed. The mean length gained was 38 mm with an average distraction index of 0,74 mm/day. WBI in these patients on average was 59,6 days/cm lengthened. 6 complications were observed, including two nonunions (successfully treated) and a knee subluxation. Mechanical axis deviation improved from 13,3 mm to 6 mm on average. Overall there has been a nonsignificant tendency for WBI to decrease (Spearman's rank correlation coefficient −0.47, p=0.08) with increasing number of cases done, while no correlation between length gained and WBI (−0.01, p=0.96, respectively) was observed. Some nuances will be discussed. Conclusions. Limb lengthening with the FITBONE nail is relatively safe and efficient, however no significant change was seen in the outcome with previous motorized nails

Unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) are well-established operative interventions in the treatment of knee osteoarthritis (KOA). However, which of these interventions is more beneficial, to patients with KOA, is not known and remains a topic of much debate. Aims: (i) To determine whether UKA or HTO is more beneficial in the treatment of isolated medial compartment KOA, via an assessment of patient-reported outcome measures (PROMs). (ii) To investigate the relationship between PROMs and radiographic parameters of knee joint orientation/alignment. This longitudinal observational study assessed a total of 42 patients that had undergone UKA (n=23) or HTO (n=19) to treat isolated medial compartment KOA. The PROMs assessed, pre-operatively and 1-year post-operatively, consisted of the: self-administered comorbidity questionnaire; short form-12; oxford knee score; knee injury and osteoarthritis outcome score; and the EQ-5D-5L. The radiographic parameters of knee joint alignment/orientation assessed, pre-operatively and 8-weeks post-operatively, included the: hip-knee-ankle angle; mechanical axis deviation; and the angle of the Mikulicz line. Statistical analysis demonstrated an overall significant (p<0.001), pre-operative to post-operative, improvement in the PROM scores of both groups. There were no significant differences in the post-operative PROM scores of the UKA and HTO group. Correlation analyses revealed that pre-operatively, a more distolaterally angled Mikulicz line was associated with worse knee function (p<0.05) and overall health (p<0.05); a relationship that, until now, has not been investigated nor commented upon within the literature. UKAs and HTOs are both efficacious operations that provide a comparable degree of clinical benefit to patients with isolated medial compartment KOA. To further the scientific/medical community's understanding of the factors that impact upon health-outcomes in KOA, future research should seek to investigate the mechanism underlying the relationship, between Mikulicz line and PROMs, observed within the current study

Introduction. Computer hexapod assisted orthopaedic surgery (CHAOS) has previously been shown to provide a predictable and safe method for correcting multiplanar femoral deformity. We report the outcomes of tibial deformity correction using CHAOS, as well as a new cohort of femoral CHAOS procedures. Materials and Methods. Retrospective review of medical records and radiographs for patients who underwent CHAOS for lower limb deformity at our tertiary centre between 2012–2020. Results. There were 70 consecutive cases from 56 patients with no loss to follow-up. Mean age was 40 years (17 to 77); 59% male. There were 48 femoral and 22 tibial procedures. Method of fixation was intramedullary nailing in 47 cases and locking plates in 23. Multiplanar correction was required in 43 cases. The largest correction of rotation was 40 degrees, and angulation was 28 degrees. Mean mechanical axis deviation reduction per procedure was 17.2 mm, maximum 89 mm. Deformity correction was mechanically satisfactory in all patients bar one who was under-corrected, requiring revision. Complications from femoral surgery included one under-correction, two cases of non-union, and one pulmonary embolism. Complications from tibial surgery were one locking plate fatigue failure, one compartment syndrome, one pseudoaneurysm of the anterior tibial artery requiring stenting, and one transient neurapraxia of the common peroneal nerve. There were no deaths. Conclusions. CHAOS can be used for reliable correction of complex deformities of both the femur and tibia. The risk profile appears to differ between femoral and tibial surgeries

Introduction. To evaluate the results of correction of knee deformities based on deformity analysis in Achondroplasia, the commonest skeletal dysplasia as some have concomitant ligamentous deformities. Materials and Methods. Retrospective study from a prospective database (2007–2020) of achondroplasts who underwent growth modulation. Analysis of medical records with objective measurement of mechanical axis radiographs was done (Traumacad). Satisfactory alignment was defined as neutral to slightly varus (0–15 mm MAD) so that the MCL/LCL laxity is not revealed. Results. 23 patients, 41 limbs, 34 bilateral, 6 unilateral underwent multiple growth modulation procedures. 2 had valgus knees. 15 patients underwent proximal fibular epiphysiodesis in addition for LCL laxity with one isolated fibular epiphysiodesis. Mechanical axis deviation (MAD) improved or normalised in 16 patients (70%). 4 patients were still undergoing correction. 4 patients needed further surgery out of which 2 patients were over 13 years when growth modulation was attempted and 2 needed correction of ankle varus. JLCA improved/ normalised in 12 patients (75%) with evidence of indirect LCL tightening and no improvement was seen in 4. The rate of correction was MAD 0.61mm/month, LDFA 0.29°/month and MPTA 0.13°/month; expectedly lower in achondroplasia due to lower growth velocity. Conclusions. This study highlights the pathology, application of growth modulation as per deformity analysis unlike previous studies. Proximal fibular epiphysiodesis improves LCL laxity in a majority of these children and is a simple procedure compared to our published series with indirect LCL tightening with frames

Introduction. We assessed the role of four different High Tibial osteotomies (HTOs) for medial compartment osteoarthritis of knee (MCOA): Medial Opening Wedge High Tibial Osteotomy (MOWHTO), Focal Dome Osteotomy with Ilizarov Fixator (FDO-I), intra-articular, Tibial Condylar Valgus Osteotomy with plating (TCVO-P) and intra-articular plus extra-articular osteotomy with Ilizarov(TCVO-I); in correcting three deformity categories: primary coronal plane varus measured by Mechanical Axis deviation (MAD), secondary intra-articular deformities measured by Condylar Plateau Angle (CPA) and Joint Line Convergence Angle (JLCA), and tertiary sagittal, rotational and axial plane deformities in choosing them. Materials and Methods. We retrospectively studied HTOs in 141 knees (126 patients). There were 58, 40, 26, and 17 knees respectively in MOWHTO, FDO-I, TCVO-P and TCVO-I. We measured preoperative (bo) And postoperative (po) deformity parameters. Results. Average age was 56.1, average follow-up was 44.6 months. Mean bo-MAD in MOWHTO, FDO-I, TCVO-P, and TCVO-I were 8.8, −14.7, −11.5, −30.8% respectively. po-MAD was close to Fujisawa point in all except TCVO-P (45.2%). CPA corrected from −4.9° to −1.4° (p=0.02)and JLCA from 5.6° to 3.2° (p=0.001); CPA was better corrected by Intra-articular osteotomies (p=0.01). Conclusions. MOWHTO corrects isolated mild primary varus deformities (bo-MAD≥ 0%). Primary varus (bo-MAD= −25% −0%) with associated tertiary sagittal, rotational, or axial deformities, without secondary intra-articular deformities needed FDO-I. Primary varus (bo-MAD= −25% −0%) with secondary intra-articular deformities, without tertiary deformities, corrected well with TCVO-P. TCVO-I corrects severe primary varus (bo-MAD< −25%) with large deformities in secondary and tertiary categories

Background. Achieving optimal prosthesis alignment during total knee arthroplasty (TKA) is essential. Imageless computer-assisted surgery (CAS) is developed to improve knee prosthesis alignment and with CAS it is possible to perform intraoperative alignment measurements. Lower limb alignment measurements are also performed for preoperative planning and postoperative evaluation. A new stereoradiography system, called EOS, can be used to perform these measurements in 3D and thus measurement errors due to malpositioning can be eliminated. Since both CAS and EOS are based on 3D modeling, measurements should theoretically correlate well. Therefore, objective was to compare intraoperative CAS-TKA measurements with pre- and postoperative EOS 3D measurements. Methods. In a prospective study 56 CAS-TKAs were performed and alignment measurements were recorded two times: before bone cuts were made and after implantation of the prosthesis. Pre- and postoperative coronal alignment measurements were performed using EOS 3D. CAS measurements were compared with EOS 3D reconstructions. Measured angles were: varus/valgus (VV), mechanical lateral distal-femoral (mLDFA) and medial proximal tibial angle (mMPTA). Results. Significantly different VV angles were measured pre- and postoperatively with CAS compared to EOS. For preoperative measurements, mLDFA did not differ significantly, but a significantly larger mMPTA in valgus was measured with CAS. Conclusions. EOS 3D measurements overestimate VV angle in lower limbs with substantial mechanical axis deviation. For lower limbs with minor mechanical axis deviation as well as for mMPTA measurements, CAS measures more valgus compared to EOS. Results of this study indicate that differences in alignment measurements between CAS measurements and pre- and postoperative EOS 3D are mainly due to the difference between weight bearing and non-weight bearing position and potential errors in validity and reliability of the CAS system. Surgeons should be aware of these measurement differences and the pitfalls of both measurement techniques. Level of evidence. IIb. Disclosures. The department of Orthopaedics, University of Groningen, University Medical Center Groningen receives research institutional support from InSpine (Schiedam, NL) and Stryker (Kalamazoo, Mich. USA). One of the authors (ALB) will be and has been paid as a consultant by Zimmer (Warsaw, IN, USA) for purposes of education and training in knee arthroplasty

Despite multiple published reviews, the optimum method of correction and stabilisation of Blount's disease remains controversial. The purpose of this study is to evaluate the clinical and radiological outcomes of acute correction of late-onset tibial vara by percutaneous proximal tibial osteotomy with circular external fixation using two simple rings. This technique was developed to minimise cost in a context of limited resources. This study was conducted between 2016 and 2020. We retrospectively reviewed the clinical notes and radiographs of 30 patients (32tibiae) who had correction of late-onset tibia by proximal tibial osteotomy and Ilizarov external fixator. All cases were followed up to 2 years. The mean proximal tibial angle was 65.7° (±7.8) preoperatively and 89.8° (±1.7) postoperatively. The mean mechanical axis deviation improved from 56.2 (±8.3) preoperatively to 2.8 (±1.6) mm postoperatively. The mean femoral-tibial shaft angle was changed from – 34.3° (±6.7) preoperatively to 5.7° (±2.8) after correction. Complications included overcorrection (9%) and pin tract infection (25%). At final follow up, all patients had full knee range of motion and normal function. All cases progressed to union and there were no cases of recurrence of deformity. This simple procedure provides secure fixation allowing early weight bearing and early return to function. It can be used in the context of health care systems with limited resources. It has a relatively low complication rate. Our results suggest that acute correction and simple circular frame fixation is an excellent treatment choice for cases of late-onset tibia vara, especially in severe deformities

C-Arm fluoroscopy is limited by its 2D imaging modality and is incapable of providing accurate 3D quantitative assessment of operative anatomy. In High Tibial Osteotomy (HTO), assessing the distance between the mechanical axis of the leg and the centre of the knee joint is difficult to accomplish due to limited fluoroscopic view size. A previously developed sensor-based tracking system (TC-Arm)adds on to C-arm equipment to provide additional quantitative capabilities. A new image-based tracking module was developed for TC-Arm using a reference panel with an array of fiducial markers. The image analysis software segments the marker positions in each image and identifies image coordinates with respect to the panel. Each image's parameters are identified by 2D-3D matching of the panel's 3D model to the marker's epipolar geometries. Finally, the defined linear transformation matrices are applied for positioning all the fluoroscopic images with respect to the same global reference. A Sawbone model of the leg was used as a phantom and marked with radio-dense fiducial markers at the centres of each joint. An Optotrak optoelectronic tracking system data was used to validate the new module's functions. First, tracking accuracy was determined by comparing orthogonal-stereo views and the reconstructed positions of the panel's design. Secondly, TC-Arm's results were compared to the corresponding digitised references points on the Sawbone model to calculate errors in the varus/valgus angle and mechanical axis deviation. The new addition to the TC-Arm has a reasonable tracking accuracy (<3.6mm, <4°) considering HTO: The system measured the mechanical axis deviation for HTO application with an accuracy of 1.3 mm and 1.4°. Comparing these results with the acceptable tolerance of less than 10 mm for MAD reported in the literature, our demonstrated results are considered to be within an acceptable range. With the new module, the capability for three-dimensional quantitative assessments of operative anatomies of any size can be added to any C-arm equipment in the OR. This can have great potential for many complex orthopaedic trauma, reconstruction, or preservation surgeries including HTO

Introduction. Deformity influences the weight bearing stresses on the knee joint. Correction of mechanical alignment is performed to offload the knee and slow the rate of degenerative change. Fixator assisted deformity correction facilitates accurate correction prior to internal fixation. We present our results with standard Ilizarov and UNYCO system assisted deformity correction of the lower limb. Materials and Methods. Retrospective analysis of adult surgical cases of mechanical re-alignment performed between 2010 and 2019 in a tertiary referral centre. We recorded standard demographics and operative time from the electronic patient record. We analysed digitalised radiographs to record pre- and post-operative measurements of: Mechanical axis deviation (MAD), femoral tibial angle (FTA), Medial Proximal tibial angle (MPTA) and Mechanical lateral distal femoral angle (mLDFA). The accuracy of the correction was analysed. Time to healing, secondary interventions and complications were also recorded. Results. 7 patients underwent fixator assisted deformity correction with the UNYCO system and 11 with a standard Ilizarov frame. Mean pre-op MAD was 45.8mm in the UNYCO group and 43.4mm in Ilazrov; Mean post-op MAD was 9.5mm in the UNYCO group (5–15) and 12.3 in the Ilizarov group (1–25) p=0.07. The average surgical time in the UNYCO group was 200 minutes (128–325) and 252 minutes (203–301) in the Ilizarov group p=0.07. The mean post op MPTA was 90.2 (87–96) in the UNYCO group and 87.4 (81–94) in the Ilizarov group. The mean mLDFA was 90.0(81–93.5) in the UNYCO group and 87.3(82.2–93.9) in the Ilizarov group. All the corrections involved a plate or nail fixation and mean time to union was 76.3 days in the UNYCO and 117.3 in the Ilizarov group. Conclusions. Both systems allowed accurate correction of deformity and limb alignment. In this small series we were unable to show a difference in theatre time. The application of the principles of deformity correction are as important as the surgical methods

Introduction and Objective. Malunion after trauma can lead to coronal plane malalignment in the lower limb. The mechanical hypothesis suggests that this alters the load distribution in the knee joint and that that this increased load may predispose to compartmental arthritis. This is generally accepted in the orthopaedic community and serves as the basis guiding deformity correction after malunion as well as congenital or insidious onset malalignment. Much of the literature surrounding the contribution of lower limb alignment to arthritis comes from cohort studies of incident osteoarthritis. There has been a causation dilemma perpetuated in a number of studies - suggesting malalignment does not contribute to, but is instead a consequence of, compartmental arthritis. In this investigation the relationship between compartmental (medial or lateral) arthritis and coronal plane malalignment (varus or valgus) in patients with post traumatic unilateral limb deformity was examined. This represents a specific niche cohort of patients in which worsened compartmental knee arthritis after extra-articular injury must rationally be attributed to malalignment. Materials and Methods. The picture archiving system was searched to identify all 1160 long leg x ray films available at a major metropolitan trauma center over a 12-year period. Images were screened for inclusion and exclusion criteria, namely patients >10 years after traumatic long bone fracture without contralateral injury or arthroplasty to give 39 cases. Alignment was measured according to established surgical standards on long leg films by 3 independent reviewers, and arthritis scores Osteoarthritis Research Society International (OARSI) and Kellegren-Lawrence (KL) were recorded independently for each compartment of both knees. Malalignment was defined conservatively as mechanical axis deviation outside of 0–20 mm medial from centre of the knee, to give 27 patients. Comparison of mean compartmental arthritis score was performed for patients with varus and valgus malalignment, using Analysis of Variance and linear regression. Results. In knees with varus malalignment there was a greater mean arthritis score in the medial compartment compared to the contralateral knee, with OARSI scores 5.69 vs 3.86 (0.32, 3.35 95% CI; p<0.05) and KL 2.92 vs 1.92 (0.38, 1.62; p<0.005). There was a similar trend in valgus knees for the lateral compartment OARSI 2.98 vs 1.84 (CI −0.16, 2.42; p=0.1) and KL 1.76 vs 1.31 (CI −0.12, 1.01; p=0.17), but the evidence was not conclusive. OARSI arthritis score was significantly associated with absolute MAD (0.7/10mm MAD, p<0.0005) and Time (0.6/decade, p=0.01) in a linear regression model. Conclusions. Malalignment in the coronal plane is correlated with worsened arthritis scores in the medial compartment for varus deformity and may similarly result in worsened lateral compartment arthritis in valgus knees. These findings support the mechanical hypothesis that arthritis may be related to altered stress distribution at the knee, larger studies may provide further conclusive evidence

Introduction. The gold standard for knee surgery is the restoration of the so-called «neutral mechanical alignment ». Recent literature as pointed out the patients with «constitutional varus »; in these cases, restoring neutral alignment could be abnormal and even undesirable. The same situation can be observed in patients with «constitutional valgus alignment ». To date, these outliers cases have only been explored focusing on the lower limb; the influence of the pelvic morphotype has not been studied. Intuitively, the pelvic width could be a significant factor. The EOS low dose imaging technique provides full body standing X-rays to evaluate the global anatomy of the patient. This work explores the influence of the pelvic parameters on the frontal knee alignment. Material and methods. – We included 170 patients (340 lower extremities). 2 operators performed measurements once per patient on AP X-rays. The classical anatomical parameters were:. –. Femoral mechanical angle (FMA). –. Tibial mechanical angle (TMA). –. Hip knee shaft angle (HKS). –. Hip knee ankle angle (HKA). –. Femoral and tibial lengths. The morphotype was evaluated by:. –. the distances between the center of two femoral heads (FHD), between knees (KD) and between ankles (AD). –. the medial neck-shaft angle (MNSA). –. the femoral offset. The horizontal distance between the limb mechanical axis (line passing from center of the femoral head to the center of the ankle) and the center of the knee was called the intrinsic mechanical axis deviation (IMAD) (fig 1). The horizontal distance between the pelvic mechanical axis (line from the center of the sacral plate to the center of the ankle) and the center of the knee was called the global mechanical axis deviation (GMAD) (fig 2). Inter-Operator Reliability was calculated with Intra-class Correlation Coefficient (ICC) and Inter-Reader Agreement was assessed with Bland-Altman test. A relationship between IMAD and GMAD to the other parameters was assessed using Pearson's correlation coefficient. Results. Inter-Operator Reliability was high for femoral offset, TMA and MSNA (ICC > 0,88) and very high for the other parameters (ICC > 0,93). These values are given in table 1 and all the 2D parameters are given in the table 2. IMAD was significantly correlated with HKA (r = 0,99), FMA (r = −0,58), TMA (r = −0,61) and KD (r = 0,72). GMAD was significantly correlated with HKA (r = 0,94), FMA (r = −0,53), TMA (r = −0,60) and KD (r = 0,67). Two groups were identified according to pelvic width (FHD):. Group 1 (standard patients): Pelvic width < 18 cm (164 lower extremities). Group 2 (wide pelvis): Pelvic width ≥ 18 cm (176 lower extremities). For standard patients the FHD is a significant parameter, whereas the proximal femoral anatomy (offset and MNSA) are more relevant for wide pelvis. Conclusion. Accurate analysis of the morphotype of the lower limbs is essential for planning femoral or tibial osteotomy and knee prostheses. Taking into account pelvic morphotype can provide additional informations for the axes restoration and the detection of outliers patients

Purpose:. We compared patients, (group A) who had severe varus deformity with posterolateral varus thrust, with patients,(group B) who didn't have varus thrust for results of total knee arthroplasty. Materials and Methods:. The average follow-up period was 33 months in group A (25 cases out of 23 patients) and 67 months in group B (50 cases out of 50 patients). We evaluated which kind of implant the patient had, the thickness of the polyethylene and changes of joint levels. Also we measured preoperative and postoperative mechanical axis deviation, tibio-femoral angle, and implant positions. Clinical results included preoperative and postoperative HSS, KSS, range of motion, and remained posterolateral instability on final follow-ups (Fig 1, Fig 2). Results:. The used implants in group A were 11 cases of Lospa®(Corentec), 10 cases of Scorpio NRG®(Stryker), 2 cases of LPS Flex®(CCK, Zimmer). The used implants in group B were 15 cases of Lospa®(Corentec). 20 cases of Scorpio NRG®(Stryker), 15 cases of LPS Flex®(Zimmer). Linked constrained prosthesis of RHK (Zimmer) was not used in any cases. The changes of mechanical axis deviations in groups A and B were respectively from preoperative average varus 66.5 mm, 32.6 mm to average varus 1.09 mm (p = 0.01), 1.8 mm (p = 0.021) in final follow-ups. Group A and Group B were corrected with statistical significance, but didn't show statistical significance between groups (p = 0.058). The changes of tibio-femoral angles were respectively from preoperative average varus 14.9°, 5.4° to average valgus 6.8°(p = 0.01), 7.6°(p = 0.013) in last follow-ups, but didn't show statistical significance between groups (p = 0.058). Preoperative stress varus angles were corrected respectively from average 18.0°, 6.2° to average 3.1°(p = 0.012), 2.3°(p = 0.064) and preoperative stress valgus angles were corrected respectively from average 9.2°, 3.0° to average 3.0°(p = 0.043), 1.9°(p = 0.068), but didn't show statistical significance in change of varus angle (p = 0.071) and in change of valgus angle (p = 0.063). Any remained posterolateral instability was not demonstrated in final follow-ups. Joint level changes in A and B were respectively from mean 13.6 mm, 12.8 mm to 18.5 mm, 17.2 mm, but didn't show statistical significance between groups (p = 0.059)(Fig 3). Postoperative implant position (α,β,γ,δ angles) was 94.6/90.3/89.7/3.86 in group A and 94.0/91.0/89.0/4.1 in group B, but didn't show statistical significance between groups (p = 0.058 in α, p = 0.061 in β, p = 0.064 in γ, p = 0.068 in γ). HSS (Hospital for Special Surgery) score improved from 47 point to 85 point (p = 0.021) in group A and from 51 point to 89 point (p = 0.032) in group B, but didn't show statistical significance between group (p = 0.061). KSS (Knee Society Scale) score was improved from 45.7 pointê. 3. ¼ to 86.2 point (p = 0.011) in group A and form 52.3 point to 88.4 point (p = 0.013), but didn't show statistical significance between group (p = 0.056). Conclusion:. Advanced osteoarthritis induced severe varus deformity with varus thrust could be effectively treated through total knee arthroplasty. But we should make a careful observation for attenuation of the lateral ligament structures in ahead. Key words: lateral ligament structures, osteoarthritis, posterolateral instability, total knee arthroplasty

Background. Ilizarov hip reconstruction is a salvage option traditionally done with fixators, which often face limited compliance. We aimed at reviewing our early results of a novel technique with internal devices. Material and Methods. Retrospective evaluation of 7 patients was done that underwent Milch Batchelor procedure with dual plates followed by a second stage femoral lengthening by retrograde magnetic nail. The mean patient age was 13.8 years. A mean valgus of 410 (range, 300 to 550) and extension of 220 (range, 100 to 300) were created proximally. Results. At their mean recent follow-up of 19 months, all extremities were aligned with a mean Pelvic Mechanical Axis Angle (PMAA) of 83.80 and lateral Mechanical Axis Deviation (MAD) of 25.3 mm. The mean Lower-extremity Length Discrepancy (LLD) improved from 3.7 cm (range, 3 to 5 cm) preoperatively to 0.7 cm (range, 0 to 2 cm). The Trendelenburg sign was eliminated in five and delayed in 2. According to a predesigned clinical scoring system, there were 3 (43%) excellent, 2 (28.5%) good, 2 (28.5%) fair, and no poor results. One patient at 9 weeks broke plates, however went for healing. Conclusion. PSHR with internal devices is a patient-friendly alternative to fixators

Purpose. The aim of this study was to compare the accuracy of limb alignment and component positioning after total knee arthroplasty(TKA) performed using fixed or individual distal femoral valgus correction angle(VCA)in valgus knees. Materials and Methods. One hundred and twenty-four patients were randomised to undergo TKA with either of the clinical baseline, radiological outcomes and subsequent outcome such as knee HSS scores, knee range of motion (ROM) and visual analogue scale (VAS) scores were assessed. Knees in the individual group (n=62) were performed with a tailored VCA. Knees in the fixed group (n=62) were performed utilizing a 4°VCA. Results. The distribution of distal femoral valgus cut angle used in the individual group range from 3° to 8°. There were statistically significant differences between groups in post-operative hip-knee-ankle angle (individual: 180.0°±3.8°; fixed: 178.5°±2.9°; P=0.00). 86.9% of patients in the individual group had a post-operative mechanical axis deviation within ± 3°compared to 70.7% in the fixed group (P = 0.03). Patients in the fixed group had a higher percentage of postoperative residual deformity than in the individual group, and this difference was statistically significant (p=0.03). No significant differences were observed between the groups in terms of femoral and component alignment except coronal femoral component angle (α), although the size of the difference was very small(individual: 90.12°±1.61°; fixed: 88.97°±2.50°), the difference was statistically significant (P=0.00). There were no differences in HSS scores, knee ROM, or VAS pain scores in the early phase after surgery between groups. Conclusions. This study demonstrated that the VCA in patients with knee valgus deformities are smaller than normal or varus knee. Individual VCA for distal femoral resection could enhance the accuracy of postoperative neutral limb alignment in the coronal plane. Both individual and fixed VCA place the components with the similar accuracy

Introduction. The range of motion (ROM) obtained after total knee arthroplasty (TKA) is an important measurement to evaluate the postoperative outcomes impacting other measures such as postoperative function and satisfaction. Flexion contracture is a recognized complication of TKA, which reduces ROM or stability and is a source of morbidity for patients. Objectives. The purpose of this study was to evaluate the influence of intra-operative soft tissue release on correction of flexion contracture in navigated TKA. Methods. This is prospective cohort study, 43 cases of primary navigation assisted TKA were included. The mean age was 68.3 ± 6.8 years. All patients were diagnosed with grade 4 degenerative arthritis in K-L grading system. The average preoperative mechanical axis deviation was 10.3° ± 5.3 and preoperative flexion contracture was 12.8° ± 4.8. All arthroplasties were performed using a medial parapatellar approach with patellar subluxation. First, medial release was performed, and posterior cruciate ligament was sacrificed. After all bone cutting was performed and femoral and tibial trials were inserted, removal of posterior femoral spur and capsular release were performed. The degree of correction of flexion contracture was evaluated and recorded with navigation. Results. After the medial soft tissue release, as a first step, the flexion contracture was recorded as 7.2° ± 4.3 and 4.1° ± 4.0 as varus. The second step, posterior cruciate ligament was sacrificed, the flexion contracture was recorded as 7.2° ± 4.4 and 5.5° ± 3.0 as varus. After posterior clearing procedure and capsular release, the flexion contracture was showed as 3.9° ± 1.2 and 1.4° ± 1.2 as varus. The final angles after cemented real implant were recorded as 3.3° ± 1.4 in flexion contracture, 0.9° ± 1.8 in varus. There were significant differences all steps except between medial release step and posterior cruciate sacrifice step and between posterior clearing step and final angle. Conclusions. The appropriate soft tissue balancing could correct flexion contracture intra-operatively. The medial release could correct the flexion contracture around 5° compared with preoperative flexion contracture, and posterior clearing procedure could improve further extension. However, the sacrifice of posterior cruciate ligament provided little effect on correction of the flexion contracture intra-operatively

Purpose. We may consider total knee arthroplasty on one knee and unicompartmental knee arthroplasty on another knee when the patient has different grade osteoarthritis on one knee and opposite knee. Both total knee and unicompartmental knee arthroplasty had been reported as excellent clinical results, but there can be different results and different preference if the same patient undergo operation of simulataneous total knee and unicompartmental knee. We performed total and unicompartmental knee arthroplasty and pretend to report results of the clinical and radiological results and rationale of the operation. Materials and Methods. From Marth 2007 to February 2014, 23 patients, 46 knees that underwent total knee arthroplasty and unicompartmental knee arthroplasty on knees with different osteoarthritis grade in same person enrolled in this study(Fig. 1). The mean age was 64.4 years old(range:55–75) and mean follow-up period was 25.1 months(range:13–72). Results. The tibiofemoral angle changed from 4.0 of varus to 5.4 of valgus in the total knee arthroplasty, and from 0.5 of valgus to 3.8 of valgus in the unicompartmental knee arthroplasty. The mechanical axis deviation changed from varus 28.35mm to varus 3.68mm in the total knee arthroplasty, and from 16.42 to 8.81 in the unicompartmental knee arthroplasty. The average Hospital for Special Surgery Knee-Rating Scale(HSS) improved from 55.1 preoperatively to 93.4 at last follow-up in the total knee arthroplasty, and from 65.2 to 95.2 in the unicompartmental knee arthroplasty. The average WOMAC Score improved from 61.6 preoperatively to 18.0 at last follow-up in the total knee arthroplasty, and from 55.4 to 16.2 in the unicompartmental knee arthroplasty. For patient preference, 5 patients(22%) preferred the unicompartmental knee arthroplasty, and 6 patients(26%) preferred the total knee arthroplasty, and 12 patients felt no difference between two knees. 20 patients(87%) reported being ‘very satisfied’ or ‘satisfied’ in the total knee arthroplasty, and 18 patients(79%) reported in the unicompartmental knee arthroplasty. We underwent 1 case complication of tibial implant loosening and varus malalignment. So, we converted total knee arthroplasty about 3 months later(Fig. 2). Conclusions. Total knee arthroplasty and unicompartmental knee arthroplasty in same person showed satisfactory clinical and radiological results. There was no difference in preference site and postoperative range of motion showed more regainment on unicompartmental knee arthroplasty. More complications were demonstrated in unicompartmental knee arthroplasty. Total and unicompartmental knee arthroplasty in same person seems to be a good option when the both knee have different osteoarthritis grade

Arthrofibrosis remains a dominant post-operative complication and reason for returning to the OR following total knee arthroplasty. Trauma induced by ligament releases during TKA soft tissue balancing and soft tissue imbalance are thought to be contributing factors to arthrofibrosis, which is commonly treated by manipulation under anesthesia (MUA). We hypothesized that a robotic-assisted ligament balancing technique where the femoral component position is planned in 3D based on ligament gap data would result in lower MUA rates than a measured resection technique where the implants are planned based solely on boney alignment data and ligaments are released afterwards to achieve balance. We also aimed to determine the degree of mechanical axis deviation from neutral that resulted from the ligament balancing technique. Methods. We retrospectively reviewed 301 consecutive primary TKA cases performed by a single surgeon. The first 102 consecutive cases were performed with a femur-first measured resection technique using computer navigation. The femoral component was positioned in neutral mechanical alignment and at 3° of external rotation relative to the posterior condylar axis. The tibia was resected perpendicular to the mechanical axis and ligaments were released as required until the soft tissues were sufficiently balanced. The subsequent 199 consecutive cases were performed with a tibia-first ligament balancing technique using a robotic-assisted TKA system. The tibia was resected perpendicular to the mechanical axis, and the relative positions of the femur and tibia were recorded in extension and flexion by inserting a spacer block of appropriate height in the medial and lateral compartments. The position, rotation, and size of the femoral component was then planned in all planes such that the ligament gaps were symmetric and balanced to within 1mm (Figure 1). Bone resection values were used to define acceptable limits of implant rotation: Femoral component alignment was adjusted to within 2° of varus or valgus, and within 0–3° of external rotation relative to the posterior condyles. Component flexion, anteroposterior and proximal-distal positioning were also adjusted to achieve balance in the sagittal plane. A robotic-assisted femoral cutting guide was then used to resect the femur according to the plan (Figure 2). CPT billing codes were reviewed to determine how many patients in each group underwent post-operative MUA. Post-operative mechanical alignment was measured in a subset of 50 consecutive patients in the ligament balancing group on standing long-leg radiographs by an independent observer. Results. Post-operative MUA rates were significantly lower in the ligament balancing group (0.5%; 1/199) than in the measured resection group (3.9%; 4/102), p=0.051. 91.3% (42/46) of knees were within 3° and 100% (46/46) were within 4° of neutral alignment to the mechanical axis post-operatively in the ligament balancing group. Conclusions. Gap driven femoral based planning in TKA resulted in a significantly lower post-operative manipulation rate than in the measured resection approach, while maintaining acceptable overall alignment to the mechanical axis

Introduction. Deformity of knee joint causes deviation of mechanical axis in the coronal plane, and the mechanical axis deviation also could adversely affect biomechanics of the ankle joint as well as the knee joint. Particularly, most of the patients undergoing total knee arthroplasty (TKA) have significant preoperative varus malalignment which would be corrected after TKA, the patients also may have significant changes of ankle joint characteristics after the surgery. This study aimed 1) to examine the prevalence of coexisting ankle osteoarthritis (OA) in the patients undergoing TKA due to varus knee OA and to determine whether the patients with coexisting ankle OA have more varus malalignment, and 2) to evaluate the changes of radiographic parameters for ankle joint before and 4 years after TKA. Methods. We evaluated 153 knees in 86 patients with varus knee OA who underwent primary TKA. With use of standing whole-limb anteroposterior radiographs and ankle radiographs before and 4 years after TKRA, we assessed prevalence of coexisting ankle OA in the patients before TKA and analyzed the changes of four radiographic parameters before and after TKA including 1) the mechanical tibiofemoral angle (negative value = varus), 2) the ankle joint orientation relative to the ground (positive value = sloping down laterally), 3) ankle joint space, and 4) medial clear space. Results. Of the 153 knees, 59 (39%) had radiographic ankle OA. The knees with ankle OA had significantly more varus mechanical tibiofemoral angle preoperatively than those without ankle OA (− 11.9° vs. − 9.3° on average, respectively; P = 0.003). Compared to the preoperative condition, the ankle joint orientation relative to the ground significantly changed after TKA (from 9.0° to 4.8° on average, P<0.001) while ankle joint space and medial clear space did not. Conclusions. Our study revealed that coexisting ankle OA would be common in patients with varus knee OA, particularly in patients with more varus malalignment. TKA also significantly changes the ankle joint orientation relative to the ground which shows more parallel to the ground. However, its effect on ankle joint space and medial clear space seems to be minimal upto 4 years after TKA. Our findings warrant consideration in preoperative evaluations of ankle OA in varus knee OA patients undergoing TKA, and further studies should evaluate prospectively the clinical implications of radiographic change of the ankle joint after TKA

Purpose. We analyzed the frequency, causes and treatment of dislocation of polyethylene insertion among various causes of failure of unicompartmental knee arthroplasty. Materials and Methods. We studied 69 knee joints of 65 patients who underwent medial unicompartmental knee arthroplasty using from June 2005 to December 2010. Average age was 61.8 and average follow-up period was 20 months. Radiologic results evaluated preoperative and postopertative mechanical axis deviation, tibio-fibular angle and postoperative implant position in total 69 knees(A group), failed 15 cases(B group) and 10 cases(C group) of bearing dislocation. We demonstrated treatment on failure group and analyzed preoperative and postoperative HSS and Lysolm score. Results. Failures were observed in 15 cases(21.7%) on follow-up. dislocation of polyethylene insertion was observed in 10 cases at average 26.7 months (3–60). There were 2 cases of dislocation of insert without loosening of implant and 8 cases of dislocation of insert with loosening of implant. Tibio-femoral angle in A, B and C group were corrected form preoperative varus 8.1°, 7.3° and 6.3° to postoperative valgus 3.6°, 4.0° and 3.5°. Thickness of inserted polyethylene in A, B and C were 4.7 mm, 5.2 mm and 4.8 mm, but each groups didn't show statistical significance. HSS and Lysolm score improvement had statistical significance. Conclusion. Dislocation of polyethylene insert (66.1%) in cases of the failure was most common. Coronal correction angle and thickness of inserted polyethylene showed no difference between dislocation gourp and non-dislocation group, so we consider that polyethylene dislocation after unicompartmental knee arthroplasty seems to be due to structural problem of the implant