We evaluated the clinical results and complications after extra-articular resection of the distal femur and/or proximal tibia and reconstruction with a tumour endoprosthesis (MUTARS) in 59 patients (mean age 33 years (11 to 74)) with malignant bone or soft-tissue tumours. According to a Kaplan–Meier analysis, limb survival was 76% (95% confidence interval (CI) 64.1 to 88.5) after a mean follow-up of 4.7 years (one month to 17 years). Peri-prosthetic infection was the most common indication for subsequent amputation (eight patients). Survival of the prosthesis without revision was 48% (95% CI 34.8 to 62.0) at two years and 25% (95% CI 11.1 to 39.9) at five years post-operatively. Failure of the prosthesis was due to deep infection in 22 patients (37%), aseptic loosening in ten patients (17%), and peri-prosthetic fracture in six patients (10%). Wear of the bearings made a minor revision necessary in 12 patients (20%). The mean Musculoskeletal Tumor Society score was 23 (10 to 29). An extensor lag > 10° was noted in ten patients (17%). These results suggest that limb salvage after extra-articular resection with a tumour prosthesis can achieve good functional results in most patients, although the rates of complications and subsequent amputation are higher than in patients treated with intra-articular resection. Cite this article: Bone Joint J 2013;95-B:1425–31

Aims. For rare cases when a tumour infiltrates into the hip joint, extra-articular resection is required to obtain a safe margin. Endoprosthetic reconstruction following tumour resection can effectively ensure local control and improve postoperative function. However, maximizing bone preservation without compromising surgical margin remains a challenge for surgeons due to the complexity of the procedure. The purpose of the current study was to report clinical outcomes of patients who underwent extra-articular resection of the hip joint using a custom-made osteotomy guide and 3D-printed endoprosthesis. Methods. We reviewed 15 patients over a five-year period (January 2017 to December 2022) who had undergone extra-articular resection of the hip joint due to malignant tumour using a custom-made osteotomy guide and 3D-printed endoprosthesis. Each of the 15 patients had a single lesion, with six originating from the acetabulum side and nine from the proximal femur. All patients had their posterior column preserved according to the surgical plan. Results. Postoperative pathological assessment revealed a negative surgical margin was achieved in all patients. At final follow-up, 13.3% (2/15) died and no recurrence occurred. The overall survival was 81.7% at five years. None of the patients showed any signs of aseptic loosening, and no wound healing issues were observed. In total, 20% (3/15) developed complications, with two cases of early hip dislocation and one case of deep infection. The cumulative incidence of mechanical and non-mechanical failure in this series was 13.7% and 9.3%, respectively, at five years. In this cohort, the mean time to full weightbearing was 5.89 (SD 0.92) weeks and the mean Musculoskeletal Tumor Society score was 24.1 (SD 4.4). Conclusion. For patients with a hip joint tumour who met the inclusion criteria and were deemed suitable for posterior column preservation, a custom-made osteotomy guide combined with 3D-printed endoprosthesis is worth performing when treating patients who require extra-articular resection of the hip joint, as it can achieve adequate margin for local control, maximize bone preservation to maintain pelvic ring integrity, reduce the risk of complications by simplifying the surgical procedure, and allow for more precise reconstruction for better function. Cite this article: Bone Jt Open 2024;5(11):1027–1036

The surgical care of extra-articular distal tibial fractures remains controversial. This study looks at the radiological outcomes of distal tibial fractures treated with either a direct medial or anterolateral plate, with or without plating of the fibula, to assess the outcome and complications associated with these 2 approaches. This is a retrospective review of 80 patients with distal tibial extra-articular fractures, treated with an open reduction and plating, between 2008 and 2019 at Glasgow Royal Infirmary. Case notes and x-rays were reviewed. Of those tibial fractures fixed with only a medial plate, 78% united (28/36), 5% (2/36) had a non-union and 17% (6/36) a malunion. In the group treated with a combination of medial tibial and fibular plating, the figures were; 71% (15/21), 19% (4/21) and 10% (2/21). However, in the group treated with anterolateral plating of the tibia alone, only 53% (8/15) united, with a 20% (3/15) non-union and 13% (2/15) malunion rate. Additionally in this group, there were 2 patients (13%) with loss of fracture reduction within the first two months of fracture fixation, requiring revision surgery. Interestingly, of the 8 patients treated with anterolateral tibial and fibular plating, 88% (7/8) showed full union and only one (12%) had a non-union, with no malunions is this group. It would appear that medial tibial and a combination of medial tibial and fibular plating, have superior outcomes compared to anterolateral plating. Results suggest, if anterolateral plating is done, this should be augmented by fixation of the fibular fracture as well

Aims. Intra-articular (IA) tumours around the knee are treated with extra-articular (EA) resection, which is associated with poor functional outcomes. We aim to evaluate the accuracy of MRI in predicting IA involvement around the knee. Methods. We identified 63 cases of high-grade sarcomas in or around the distal femur that underwent an EA resection from a prospectively maintained database (January 1996 to April 2020). Suspicion of IA disease was noted in 52 cases, six had IA pathological fracture, two had an effusion, two had prior surgical intervention (curettage/IA intervention), and one had an osseous metastasis in the proximal tibia. To ascertain validity, two musculoskeletal radiologists (R1, R2) reviewed the preoperative imaging (MRI) of 63 consecutive cases on two occasions six weeks apart. The radiological criteria for IA disease comprised evidence of tumour extension within the suprapatellar pouch, intercondylar notch, extension along medial/lateral retinaculum, and presence of IA fracture. The radiological predictions were then confirmed with the final histopathology of the resected specimens. Results. The resection histology revealed 23 cases (36.5%) showing IA disease involvement compared with 40 cases without (62%). The intraobserver variability of R1 was 0.85 (p < 0.001) compared to R2 with κ = 0.21 (p = 0.007). The interobserver variability was κ = 0.264 (p = 0.003). Knee effusion was found to be the most sensitive indicator of IA involvement, with a sensitivity of 91.3% but specificity of only 35%. However, when combined with a pathological fracture, this rose to 97.5% and 100% when disease was visible in Hoffa’s fat pad. Conclusion. MRI imaging can sometimes overestimate IA joint involvement and needs to be correlated with clinical signs. In the light of our findings, we would recommend EA resections when imaging shows effusion combined with either disease in Hoffa’s fat pad or retinaculum, or pathological fractures. Cite this article: Bone Joint J 2023;105-B(6):696–701

This annotation considers the place of extra-articular reconstruction in the treatment of anterior cruciate ligament (ACL) deficiency. Extra-articular reconstruction has been employed over the last century to address ACL deficiency. However, the technique has not gained favour, primarily due to residual instability and the subsequent development of degenerative changes in the lateral compartment of the knee. Thus intra-articular reconstruction has become the technique of choice. However, intra-articular reconstruction does not restore normal knee kinematics. Some authors have recommended extra-articular reconstruction in conjunction with an intra-articular technique. . The anatomy and biomechanics of the anterolateral structures of the knee remain largely undetermined. Further studies to establish the structure and function of the anterolateral structures may lead to more anatomical extra-articular reconstruction techniques that supplement intra-articular reconstruction. This might reduce residual pivot shift after an intra-articular reconstruction and thus improve the post-operative kinematics of the knee.

Abstract. Introduction. The aim of this study was to determine if elite athletes could return to professional sport after MCL or PLC reconstruction using LARS ligaments and to demonstrate the safety and efficacy of LARS by reporting sport longevity, subsequent surgeries and complications. Methods. A retrospective review of all extra-articular knee ligament reconstructions in elite athletes utilising LARS ligaments by 3 knee surgeons between January 2013 and October 2020 was undertaken. Return to play (RTP) was defined as competing at professional level or national/ international level in amateur sport. Results. Sixty-four (84.2%) MCL and 12 (15.8%) PLC reconstructions utilising LARS in elite athletes were included. 52 (68.4%) underwent concomitant cruciate(s) reconstruction. The mean age was 25.1 years (SD +/− 4.50. Most were football (35, 46.1%) or rugby players (35, 46.1%). Sixty-seven athletes (88.2%) RTP with 65 (97.0%) of these playing at the same or higher Tegner level. 56 (83.6%) and 20 (57.1%) were still playing at 2 and 5 years post-surgery. Six (7.9%) players (5 of whom RTP) required further surgery relating to the LARS / metalwork and there was one case of adverse local inflammatory reaction to the synthetic material. There was one MCL re-rupture, sustained 4 years after RTP. Conclusion. Utilising LARS in extra-articular knee ligament reconstructions allows 88.2% of athletes, with a variety of knee ligament injuries, to return to elite sport. The low morbidity rates coupled with 57% of athletes still playing 5 years post-surgery suggests the LARS is safe and effective in these cases

Introduction. To determine if elite athletes can return to professional sport after MCL or posterolateral (PLC) reconstruction using LARS ligaments. The secondary aims are to demonstrate the safety and efficacy of LARS by reporting sport longevity, subsequent surgeries, and complications. Methods. A retrospective review of all extra-articular knee ligament reconstructions, utilising a LARS synthetic ligament, by 3 sports knee surgeons between 2013 and 2020 was undertaken. All elite athletes aged over 16 years and a minimum of 2 years post reconstruction were included. No LARS were used for ACL reconstructions, and they were excluded if a LARS ligament was used for a PCL reconstruction. Return to play (RTP) was defined as competing at professional level or national/ international level in amateur sport. Results. Sixty-four (84.2%) MCL reconstructions and 12 (15.8%) PLC reconstructions were included. 52 (68.4%) underwent concomitant autograft cruciate(s) reconstruction including 6 (7.8%) bicruciate reconstructions. The mean age was 25.1 years (SD +/− 4.50). 35 (46.1%) were footballers and 35 (46.1%) were rugby players. Sixty-seven athletes (88.2%) returned to elite sport, 7 (9.2%) did not RTP and RTP status was unknown for 2 (2.6%) (Figure 1). 65 out of 67 (97.0%) RTP at the same/higher Tegner level. 56 (83.6%) and 20 (57.1%) were still playing at 2- and 5-years post-surgery Six (7.9%) players required further surgery due to irritation from the metal fixation implants. One had an inflammation adjacent to the synthetic material at the femoral end and the other cases involved the tibial staples. All six cases were able to RTP. One athlete, following bicruciate /MCL surgery had the LARS removed due to laxity. There was one MCL re-rupture, sustained while jumping, 4 years after returning to football. Conclusions. Utilising LARS in extra-articular knee ligament reconstructions allows 88.2% of athletes with a variety of knee ligament injuries to return to elite sport. The results compare well regarding RTP, complication, and revision rates with the published evidence for other types of MCL and PLC grafts. This, coupled with 57% of athletes still playing 5 years post-surgery suggests the LARS is safe and effective in these cases. For any figures or tables, please contact authors directly

Abstract. Introduction. Anterolateral procedures can reduce the risk of re-rupture after ACL reconstruction in high risk patients however, this effectiveness has never been evaluated in elite athletes. The purpose of this study was to evaluate the effectiveness of lateral extra-articular tenodesis in reducing revision rates in ACL reconstructions in elite athletes. Methodology. A consecutive cohort of elite athletes between 2005 and 2018 undergoing ACLR reconstruction with or without modified Lemaire lateral extra-articular tenodesis were analysed. A minimum of 2 years of follow-up was required. The association between the use of LET and ACL graft failure was evaluated with univariate and multivariate logistic regression models. Results. 455 elite athletes (83% male; 22.5±4.7 years) underwent primary ACL reconstruction with (n=117) or without (n=338) a LET procedure. Overall, 36 athletes (7.9%) experienced ACL graft failure including 32 (9.5%) reconstructions without a LET and 4 (3.4%) with a LET. Utilization of LET during primary ACL reconstruction reduced the risk of graft failure by 2.8 times with 16.5 athletes needing to be treated with LET to prevent a single ACL graft failure. Multivariate models showed that LET significantly reduced the risk of graft rupture (RR=0.325; p=.029) as compared to ACL reconstruction alone after controlling for age at ACL reconstruction and gender. Including graft type in the model did not significantly change the risk profile. Conclusion. The addition of LET in elite athletes undergoing primary ACL reconstruction reduced the risk of undergoing revision by 2.8 times

Abstract. Background. Performing lateral extra-articular tenodesis (LET) with ACL reconstruction may conflict with the ACLR femoral tunnel. Methods. 12 fresh-frozen cadaveric knees were used: at 120 flexion, an 8mm ACLR femoral tunnel was drilled in the anteromedial bundle position via the anteromedial portal. A modified Lemaire LET was performed using a 1 cm-wide iliotibial band strip left attached to Gerdy's tubercle. The LET femoral fixation point was identified 10mm proximal / 5 mm posterior to the LCL femoral attachment, and a 2.4-mm guide wire was drilled, aiming at 0, 10, 20, or 30 degrees anteriorly in the axial plane, and at 0, 10, or 20 degrees proximally in the coronal plane. The relationship between the LET drilling guide wire and the ACLR femoral tunnel reamer was recorded for each combination. When collision with the femoral tunnel was recorded, the LET wire depth was measured. Results. Tunnel conflict occurred at a mean LET wire depth of 23.6 mm (15–33 mm). No correlation existed between LET wire depth and LET drilling orientation (r=0.066; p=0.67). Drilling angle in the axial plane was significantly associated with the occurrence of tunnel conflict (P < .001). However, no such association was detected when comparing the drilling angle in the coronal plane (P=0.267). Conclusion. Conflict occurred at as little as 15 mm depth. When longer implants are used, the orientation should be at least 30 degrees anterior in the axial plane. Clinical Relevance. This study provides important information for surgeons performing LET in combination with ACLR

Extra-articular deformity may be present in patients requiring TKA. Underlying causes include trauma, metabolic bone disease, congenital deformity, or prior osteotomy. Patients with intra-articular deformity have a combination of intra-articular bone loss and concomitant ligament contraction which can be managed in the standard fashion. In these cases establishing appropriate limb alignment and management of bone loss coincide well with the standard ligament balancing employed to provide a stable knee. However, if extra-articular deformity is not corrected extra-articularly, it must be corrected by a compensatory distal femoral or proximal tibial resection to reproduce appropriate limb alignment. Complex instabilities may result from this type of wedge resection because it occurs between the proximal and distal attachments of the collateral ligaments and so produces asymmetrical ligament length alterations. Femoral compensatory wedge resection for extra-articular deformity produces extension instability without affecting the flexion gap and so femoral deformities are POTENTIALLY more difficult to correct than tibial deformities where the compensatory tibial cut influences flexion AND extension equally. Lack of access to the intramedullary canal (as well as increased complexity of producing appropriately placed bone cuts) may be managed with computer guidance or patient specific instruments. The closer a deformity is to the knee, the greater its importance and the effect on the surgical correction. This is a directly proportional relationship, so that as the apex of the deformity moves from juxta-articular to more distant, the amount of corrective wedge needed to re-align the limb decreases proportionally. Rotatory deformities most commonly effect extensor mechanism tracking. The effect is similar to any other deformity in that proximity to the knee and increases the likelihood that it will have a significant local effect. In general, these deformities may be clinically, and radiographically more subtle and so must be searched for. They should be managed by restoring normal rotational parameters of the bone or by appropriate compensation of component rotation relative to the bone. As the need for prosthetic constraint increases due to ligament imbalance or deficiency, intramedullary stems may be required. Their use may be compromised by the presence of the deformity. The younger the patient and the more severe the deformity the more likely I am to treat the deformity by correction at the site of the deformity rather than compensating with abnormal bone resections. The older the patient and the milder the deformity (or the amount of correction required) the more intra-articular correction +/− increased TKA constraint is feasible

Deformity can be associated with significant bone loss, ligament laxity, soft-tissue contractures, distortion of long bone morphology, and extra-articular deformity. Correction of varus, valgus, or flexion deformity requires soft tissue releases in conjunction with bone cuts perpendicular to the long axes of the femur and tibia. Cruciate-retaining or -substituting implants can be used based on surgeon preference if the ligaments are well balanced. However, in presence of severe deformity, additional measures may be warranted to achieve alignment and balance. TKA then becomes a more challenging proposition and may require the surgeon to perform extensive releases, adjunct osteotomies and deploy more constrained implants. Merely enhancing constraint in the implant, however, without attending to releases and extra-articular correction may not suffice. Pre-operative planning, i.e., whether intra-articular correction alone will suffice or extra-articular correction is required, will be highlighted. Surgical principles and methods of performing large releases, reduction osteotomy, lateral epicondylar sliding osteotomy, sliding medial condylar osteotomy, and closed wedge diaphyseal/metaphyseal osteotomy concomitantly with TKA will be illustrated with examples. Results of a large series of TKA with extra-articular deformity resulting from coronal bowing of femoral or tibial diaphysis, malunited fractures, prior osteotomies, and stress fractures will be presented. The techniques reported can successfully restore alignment, pain-free motion, and stability without necessarily using more constrained implants

We performed a prospective, randomised study on 57 patients older than 60 years of age with unstable, extra-articular fractures of the distal radius to compare the outcome of immobilisation in a cast alone with that using supplementary, percutaneous pinning. Patients treated by percutaneous wires had a statistically significant improvement in dorsal angulation (mean 7°), radial length (mean 3 mm) and radial inclination (mean 3 mm) at one year. However, there was no significant difference in functional outcome in terms of pain, range of movement, grip strength, activities of daily living and the SF-36 score except for an improved range of movement in ulnar deviation in the percutaneous wire group. One patient developed a pin-track infection which required removal of the wires at two weeks. We conclude that percutaneous pinning of unstable, extra-articular fractures of the distal radius provides only a marginal improvement in the radiological parameters compared with immobilisation in a cast alone. This does not correlate with an improved functional outcome in a low-demand, elderly population

Extra-articular deformity may be present in patients requiring TKA. Underlying causes include trauma, metabolic bone disease, congenital deformity, or prior osteotomy. Patients with intra-articular deformity can have a combination of intra-articular bone loss and concomitant ligament contraction which can be managed in the standard fashion. In these cases establishing appropriate limb alignment and management of bone loss coincide well with the standard ligament balancing employed to provide a stable knee. However, if extra-articular deformity is not corrected extra-articularly, it must be corrected by a compensatory distal femoral or proximal tibial resection to reproduce appropriate limb alignment. Complex instabilities may result from this type of wedge resection because it occurs between the proximal and distal attachments of the collateral ligaments and so produces asymmetrical ligament length alterations. Femoral compensatory wedge resection for extra-articular deformity produces extension instability without affecting the flexion gap and so femoral deformities are POTENTIALLY more difficult to correct than tibial deformities where the compensatory tibial cut influences flexion AND extension equally. Lack of access to the intramedullary canal (as well as increased complexity of producing appropriately placed bone cuts) may be managed with computer guidance or patient specific instruments. The closer a deformity is to the knee, the greater its importance and the effect on the surgical correction. This is a directly proportional relationship, so that as the apex of the deformity moves from juxta-articular to more distant, the amount of corrective wedge needed to re-align the limb decreases proportionally. Rotatory deformities are complex and most commonly effect extensor mechanism tracking. In general the effect is similar to any other deformity in that proximity to the knee increases the likelihood that it will have a significant local effect. In general, these deformities are clinically, and radiographically more subtle and so must be searched for. They should be managed by an attempt to restore normal rotational parameters of the bone itself or appropriate compensation of component rotation in relation to the bone. As prosthetic constraint increases one may need to use intramedullary stems. Their use may be compromised by the deformity. Finally, the younger the patient and the more severe the deformity the more likely I am to treat the deformity by correction at the site of the deformity rather than compensating with abnormal bone resections. The older the patient and the milder the deformity (or the amount of wedge correction required) the more likely I am to manage the deformity with intra-articular correction and increased TKA constraint

Introduction. Restoration of mechanical axis is one of the main aims during Total Knee Arthroplasty (TKA) surgery. Treatment of osteoarthritis (OA) of the knee with extra-articular deformity either in femur or in tibia poses a technical challenge in achieving this aim. Insufficient correction of axis is associated with poor clinical outcome of total knee arthroplasty (TKA). Extra-articular deformity can either be addressed with compensatory intra-articular bone resection at the time of TKA or correctional osteotomy prior to or at the time of TKA. Patients & Methods & Results. We present our experience of treating 7 patients with knee arthritis (9 knees) and significant extra-articular deformity. Two patients had OA knee with severe valgus deformity in tibia from recurrent stress fractures. One was treated with one-stage corrective osteotomy and long stem modular TKA. The other had deformity correction with two level tibial osteotomy with intramedullary nail and modular long stem TKA later. Both required tibial tubercle osteotomy during TKA. Two patients with bilateral OA knees and significant varus deformity had sequential deformity correction with Taylor Spatial Frame (TSF) followed by TKA on one side and a single stage intra-articular correction during TKA on the other. Three patients with knee OA and associated deformity (femoral - two pt., tibia one pt.) had symptom resolution with just correction of malaligment with Taylor Spatial Frame (TSF) and did not require TKA. Conclusion. Complex extra-articular femoral or tibial deformities may require proper limb realignment prior to TKA. Our series supports all three approaches to correcting significant extra-articular deformity with knee OA. Each case should be considered individually and planned accordingly

Introduction. Bone tumours rarely involve the joint surface as cartilage is thought to be a good barrier to tumour spread. When the tumour does cross the surface the surgeon is faced with the dilemma of whether to amputate the limb, resect it without reconstruction or reconstruct with an implant. This paper aims to investigate the oncological and functional outcomes of patients undergoing an extra-articular resection and reconstruction with an endoprosthesis. Method. 3100 patients have been seen in ROH with primary bone tumours. Patients were identified who had an extra-articular resection considered pre-operatively and the notes and imaging was reviewed. This group was subdivided into a group who did have an extra-articular resection (EAR) and those who either had an amputation or traditional through joint resection. The outcomes of the three groups (group 1 = no joint involvement, group 2 = EAR considered but not done and group 3 = EAR) were then compared in terms of oncological outcome, surgical margins and complications. Results. EAR was considered in 94 cases (3%) usually due to either obvious tumour or joint effusion on initial imaging. Of these 94 cases an EAR was undertaken in 66 cases and not in 28 cases. There was no difference in age, site distribution, diagnosis between the groups. The mean size of the tumour was smaller in the EAR group. The percentage of wide margins achieved was significantly smaller in the EAR group and risk of local recurrent disease was greater in the EAR group but mainly in patients with chondrosarcoma. There was no difference in patient survival between the groups. Conclusions. EAR gives acceptable oncological and functional results but has significantly higher rates of locally recurrent disease in patients with chondrosarcoma

The aim of this review is to evaluate the current available literature evidencing on peri-articular hip endoscopy (the third compartment). A comprehensive approach has been set on reports dealing with endoscopic surgery for recalcitrant trochanteric bursitis, snapping hip (or coxa-saltans; external and internal), gluteus medius and minimus tears and endoscopy (or arthroscopy) after total hip arthroplasty. This information can be used to trigger further research, innovation and education in extra-articular hip endoscopy

Aims. The aims of this retrospective study were to determine the incidence of extra-articular deformities (EADs), and determine their effect on postoperative alignment in knees undergoing mobile-bearing, medial unicompartmental knee arthroplasty (UKA). Patients and Methods. Limb mechanical alignment (hip-knee-ankle angle), coronal bowing of the femoral shaft and proximal tibia vara or medial proximal tibial angle (MPTA) were measured on standing, full-length hip-to-ankle radiographs of 162 patients who underwent 200 mobile-bearing, medial UKAs. Results. Incidence of EAD was 7.5% for coronal femoral bowing of >5°, 67% for proximal tibia vara of >3° (MPTA<87°) and 24.5% for proximal tibia vara of >6° (MPTA<84°). Mean postoperative HKA angle achieved in knees with femoral bowing ≤5° was significantly greater when compared to knees with femoral bowing >5° (p=0.04); in knees with proximal tibia vara ≤3° was significantly greater when compared to knees with proximal tibia vara >3° (p=0.0001) and when compared to knees with proximal tibia vara >6° (p=0.0001). Conclusion. Extra-articular deformities are frequently seen in patients undergoing mobile-bearing medial UKAs, especially in knees with varus deformity>10°. Presence of an EAD significantly affects postoperative mechanical limb alignment achieved when compared to limbs without EAD and may increase the risk of limbs being placed in varus>3° postoperatively. Clinical Relevance. Since the presence of an EAD, especially in knees with varus deformity>10°, may increase the risk of limbs being placed in varus>3° postoperatively and may affect long-term clinical and implant survival outcomes, UKR in such knees should be performed with caution

Total knee arthroplasty becomes more challenging when knee arthritis is associated with an extra-articular deformity of the femur or tibia. We evaluated the outcome of navigated total knee arthroplasty in a large series of arthritic knees with extra-articular deformity. We retrospectively reviewed the records of 950 patients who had undergone navigated TKA between January 2005 and February 2008. There were 40 extra-articular deformities in 34 patients, with bilateral involvement in 6 patients which were included in the study. Twenty-two limbs had deformity in the femur and the tibia had deformity in 18 limbs. There were 24 females and 10 males with a mean age of 63.1 years (range, 46–80 years). The etiologies included malunited fractures (13 patients), stress fractures (4 patients), post high tibial osteotomy (3 patients), and excessive coronal bowing (14 patients). The mean femoral extra-articular deformity in the coronal plane was 9.3° varus (range, 24° varus to 2.8° varus) and the mean tibial extra-articular deformity in the coronal plane was 6.3° varus (range, 20° varus to 8.5° valgus). Three limbs underwent simultaneous corrective osteotomy and the rest were treated with intra-articular correction during computer-assisted total knee arthroplasty. The limb alignment changed from a mean of 166.7° preoperatively to 179.1° postoperatively. At a mean follow-up of 26.4 months, the Knee Society knee score improved from a mean pre-operative score of 49.7 points to 90.4 points postoperatively; function score improved from 47.3 points to 84.9 points. The results of our study indicate that computer-assisted total knee arthroplasty is a useful alternative to conventional total knee arthroplasty for knee arthritis with extraarticular deformity where accurate restoration of limb alignment may be challenging due to the presence of a deformed tibia or femur or in the presence of hardware

The treatment of patients with osteoarthritis of the knee and associated extra-articular deformity of the leg is challenging. Current teaching recognises two possible approaches: (1) a total knee replacement (TKR) with intra-articular bone resections to correct the malalignment or (2) an extra-articular osteotomy to correct the malalignment together with a TKR (either simultaneously or staged). However, a number of these patients only have unicompartmental knee osteoarthritis and, in the absence of an extra-articular deformity would be ideal candidates for joint preserving surgery such as unicompartmental knee replacement (UKR) given its superior functional outcome and lower cost relative to a TKR [1). We report four cases of medial unicondylar knee replacement, with a simultaneous extra-articular osteotomy to correct deformity, using novel 3D printed patient-specific guides (Embody, UK) (see Figure 1). The procedure was successful in all four patients, and there were no complications. A mean increase in the Oxford knee score of 9.5, and in the EQ5D VAS of 15 was observed. To our knowledge this is the first report of combined osteotomy and unicompartmental knee replacement for the treatment of extra-articular deformity and knee osteoarthritis. This technically challenging procedure is made possible by a novel 3D printed patient-specific guide which controls osteotomy position, degree of deformity correction (multi-plane if required), and orientates the saw-cuts for the unicompartmental prosthesis according to the corrected leg alignment. Using 3D printed surgical guides to perform operations not previously possible represents a paradigm shift in knee surgery. We suggest that this joint preserving approach should be considered the preferred treatment option for suitable patients

Introduction. Arthritic knees requiring total knee replacement may present with additional deformities located along the femur or tibia away from the articular region. These deformities may be congenital, developmental, associated with metabolic bone disease, or acquired as a result of malunited fractures or previous advocated for arthritic knee with ipsilateral extra-articular deformity. Methods. We undertook retrospective study to evaluate the results of total knee arthroplasty in arthritic knee with extra-articular deformity in 26 knees (24 patients). Sixteen deformities were in tibia and ten deformities were in femur. All patients underwent total knee arthroplasty with intraarticular bone resection and soft tissue balancing. Results. Average period of follow up was 30 months. Average preoperative arc of motion was 57.5 degrees, which improved to 102.5 degrees. The average preoperative knee society knee score 23.5 points, which improved to an average of 91.3 points at the time of last follow up. The average functional score was 27.0 points, which improved to average of 88.0 points. There were no complications such as infection, ligament instability or component loosening. Conclusion. Intra-articular bone resection is an effective procedure for management of arthritic knees with extra-articular deformity