Abstract. Introduction. Anterior cruciate ligament reconstruction (ACLR) can be performed with a number of different autografts including all soft tissue quadriceps autograft. (QT). QT has several advantages including decreased donor site morbidity, reduced anterior knee pain and comparable revision rates compared to other autografts. The primary aim of this review was to assess all complications of QT in adult population. Methodology. A systematic review of the literature was conducted on in accordance with the PRISMA guidelines using the online databases Medline and EMBASE. Clinical studies or reporting on soft tissue QT were included and appraised using the Methodological Index for Non-Randomized Studies (MINORS) tool. Results. Twelve studies were eligible, giving a total of 774 cases of QT ACLR. The mean age ranged from 18 to 45 years. The mean follow-up ranged from 12 to 55.6 months. Nine studies report on patients’ functional outcomes with mean IKDC score was 90.9 ±22.6 and Lysholm score of 88.6 ±6.5. Seven studies reported on complications which was overall 12.3% including 4.1% for graft site morbidity. Infection was reported in 0.4% of the patients. Seven studies reported on failure rate which was reported in 5.3%. Re-operation rate for any reason was 3.2 %. Conclusion. All soft tissue QT for ACLR has a low complication rate and revision rate. There is less graft site morbidity

Abstract. Introduction. The knee is the most commonly injured joint in sporting accidents. They cause substantial disability, time off work and long-term problems. There remains a limited number of high-quality randomised controlled trials assessing first time, acute soft tissue knee injuries. Key areas requiring answers include prevention, diagnosis, treatment, rehabilitation and delivery of care. In association with the James Lind Alliance, this BASK, BOSTAA and BOA supported prioritising exercise was undertaken over a year. Methodology. The James Lind Alliance methodology was followed. An initial survey invited patients and healthcare professionals to submit their uncertainties regarding soft tissue knee injury prevention, diagnosis, treatment, rehabilitation and delivery of care. Over 1000 questions were submitted. Seventy-four questions were formulated to encompass common concerns. These were checked against best available evidence. Following the interim survey, 27 questions were taken forward to the final workshop in January 2023, where they were discussed, ranked and scored in multiple rounds of prioritisation by groups of healthcare professionals, patients and carers. Results. The Top 10 includes prevention, diagnosis, treatment and rehabilitation questions, reflecting the concerns of patients, carers and a wider multidisciplinary team. These will be presented and explained. Conclusion. This validated process has generated an important Top 10, which has been submitted to the National Institute for Health and Care Research. All 27 questions will be published, thus being available for researchers to investigate. The questions in the Top 10 will lead to future high quality research, thus improving patient outcomes

Aims. The integrity of the soft tissue envelope is crucial for successful treatment of infected total knee arthroplasty (TKA). The purpose of this study was to evaluate the rate of limb salvage, infection control, and clinical function following microvascular free flap coverage for salvage of the infected TKA. Methods. We retrospectively reviewed 23 microvascular free tissue transfers for management of soft tissue defects in infected TKA. There were 16 men and seven women with a mean age of 61.2 years (39 to 81). The median number of procedures performed prior to soft tissue coverage was five (2 to 9) and all patients had failed at least one two-stage reimplantation procedure. Clinical outcomes were measured using the Knee Society Scoring system for pain and function. Results. In all, one patient was lost to follow-up prior to 12 months. The remaining 22 patients were followed for a mean of 46 months (12 to 92). At latest follow-up, four patients (18%) had undergone amputation for failure of treatment and persistent infection. For the other 18 patients, 11 patients (50%) had maintained a knee prosthesis in place while seven patients had undergone resections for persistent infection but retained their limbs (32%). Reoperations were common following coverage and reimplantation. The median number of additional procedures was two (0 to 6). Clinical function was poor in patients who underwent reimplantation and retained a knee prosthesis following free flap coverage with a mean KSS score for pain and function of 44 (0 to 70) and 30 (0 to 65), respectively. All patients required an assistive device. Extensor mechanism problems and extensor lag requiring bracing were common following limb salvage and prosthesis reimplantation. Conclusion. Microvascular tissue transfer for management of infected TKA can be successful in limb salvage (82%) but clinical outcomes in salvaged limbs were poor. Cite this article: Bone Joint J 2020;102-B(6 Supple A):176–180

Aims. The aims of this study were to determine the effect of osteophyte excision on deformity correction and soft tissue gap balance in varus knees undergoing computer-assisted total knee arthroplasty (TKA). Methods. A total of 492 consecutive, cemented, cruciate-substituting TKAs performed for varus osteoarthritis were studied. After exposure and excision of both cruciates and menisci, it was noted from operative records the corrective interventions performed in each case. Knees in which no releases after the initial exposure, those which had only osteophyte excision, and those in which further interventions were performed were identified. From recorded navigation data, coronal and sagittal limb alignment, knee flexion range, and medial and lateral gap distances in maximum knee extension and 90° knee flexion with maximal varus and valgus stresses, were established, initially after exposure and excision of both cruciate ligaments, and then also at trialling. Knees were defined as ‘aligned’ if the hip-knee-ankle axis was between 177° and 180°, (0° to 3° varus) and ‘balanced’ if medial and lateral gaps in extension and at 90° flexion were within 2 mm of each other. Results. Of 50 knees (10%) with no soft tissue releases (other than cruciate ligaments), 90% were aligned, 81% were balanced, and 73% were aligned and balanced. In 288 knees (59%) only osteophyte excision was performed by subperiosteally releasing the deep medial collateral ligament. Of these, 98% were aligned, 80% were balanced, and 79% were aligned and balanced. In 154 knees (31%), additional procedures were performed (reduction osteotomy, posterior capsular release, and semimembranosus release). Of these, 89% were aligned, 68% were balanced, and 66% were aligned and balanced. The superficial medial collateral ligament was not released in any case. Conclusion. Two-thirds of all knees could be aligned and balanced with release of the cruciate ligaments alone and excision of osteophytes. Excision of osteophytes can be a useful step towards achieving deformity correction and gap balance without having to resort to soft tissue release in varus knees while maintaining classical coronal and sagittal alignment of components. Cite this article: Bone Joint J 2020;102-B(6 Supple A):49–58

Aims. The objectives of this study were to assess the effect of anterior cruciate ligament (ACL) resection on flexion-extension gaps, mediolateral soft tissue laxity, maximum knee extension, and limb alignment during primary total knee arthroplasty (TKA). Methods. This prospective study included 140 patients with symptomatic knee osteoarthritis undergoing primary robotic-arm assisted TKA. All operative procedures were performed by a single surgeon using a standard medial parapatellar approach. Optical motion capture technology with fixed femoral and tibial registration pins was used to assess study outcomes pre- and post-ACL resection with knee extension and 90° knee flexion. This study included 76 males (54.3%) and 64 females (45.7%) with a mean age of 64.1 years (SD 6.8) at time of surgery. Mean preoperative hip-knee-ankle deformity was 6.1° varus (SD 4.6° varus). Results. ACL resection increased the mean extension gap significantly more than the flexion gap in the medial (mean 1.2 mm (SD 1.0) versus mean 0.2 mm (SD 0.7) respectively; p < 0.001) and lateral (mean 1.1 mm (SD 0.9) versus mean 0.2 mm (SD 0.6) respectively; p < 0.001) compartments. The mean gap differences following ACL resection did not create any significant mediolateral soft tissue laxity in extension (gap difference: mean 0.1 mm (SD 2.4); p = 0.89) or flexion (gap difference: mean 0.2 mm (SD 3.1); p = 0.40). ACL resection did not significantly affect maximum knee extension (change in maximum knee extension = mean 0.2° (SD 0.7°); p = 0.23) or fixed flexion deformity (mean 4.2° (SD 3.2°) pre-ACL release versus mean 3.9° (SD 3.7°) post-ACL release; p = 0.61). ACL resection did not significantly affect overall limb alignment (change in alignment = mean 0.2° valgus (SD 1.0° valgus; p = 0.11). Conclusion. ACL resection creates flexion-extension mismatch by increasing the extension gap more than the flexion gap. However, gap differences following ACL resection do not create any mediolateral soft tissue laxity in extension or flexion. ACL resection does not affect maximum knee extension or overall limb alignment. Cite this article: Bone Joint J 2020;102-B(4):442–448

Aims. A comprehensive classification for coronal lower limb alignment with predictive capabilities for knee balance would be beneficial in total knee arthroplasty (TKA). This paper describes the Coronal Plane Alignment of the Knee (CPAK) classification and examines its utility in preoperative soft tissue balance prediction, comparing kinematic alignment (KA) to mechanical alignment (MA). Methods. A radiological analysis of 500 healthy and 500 osteoarthritic (OA) knees was used to assess the applicability of the CPAK classification. CPAK comprises nine phenotypes based on the arithmetic HKA (aHKA) that estimates constitutional limb alignment and joint line obliquity (JLO). Intraoperative balance was compared within each phenotype in a cohort of 138 computer-assisted TKAs randomized to KA or MA. Primary outcomes included descriptive analyses of healthy and OA groups per CPAK type, and comparison of balance at 10° of flexion within each type. Secondary outcomes assessed balance at 45° and 90° and bone recuts required to achieve final knee balance within each CPAK type. Results. There was similar frequency distribution between healthy and arthritic groups across all CPAK types. The most common categories were Type II (39.2% healthy vs 32.2% OA), Type I (26.4% healthy vs 19.4% OA) and Type V (15.4% healthy vs 14.6% OA). CPAK Types VII, VIII, and IX were rare in both populations. Across all CPAK types, a greater proportion of KA TKAs achieved optimal balance compared to MA. This effect was largest, and statistically significant, in CPAK Types I (100% KA vs 15% MA; p < 0.001), Type II (78% KA vs 46% MA; p = 0.018). and Type IV (89% KA vs 0% MA; p < 0.001). Conclusion. CPAK is a pragmatic, comprehensive classification for coronal knee alignment, based on constitutional alignment and JLO, that can be used in healthy and arthritic knees. CPAK identifies which knee phenotypes may benefit most from KA when optimization of soft tissue balance is prioritized. Further, it will allow for consistency of reporting in future studies. Cite this article: Bone Joint J 2021;103-B(2):329–337

Aims. It is unknown whether gap laxities measured in robotic arm-assisted total knee arthroplasty (TKA) correlate to load sensor measurements. The aim of this study was to determine whether symmetry of the maximum medial and lateral gaps in extension and flexion was predictive of knee balance in extension and flexion respectively using different maximum thresholds of intercompartmental load difference (ICLD) to define balance. Methods. A prospective cohort study of 165 patients undergoing functionally-aligned TKA was performed (176 TKAs). With trial components in situ, medial and lateral extension and flexion gaps were measured using robotic navigation while applying valgus and varus forces. The ICLD between medial and lateral compartments was measured in extension and flexion with the load sensor. The null hypothesis was that stressed gap symmetry would not correlate directly with sensor-defined soft tissue balance. Results. In TKAs with a stressed medial-lateral gap difference of ≤1 mm, 147 (89%) had an ICLD of ≤15 lb in extension, and 112 (84%) had an ICLD of ≤ 15 lb in flexion; 157 (95%) had an ICLD ≤ 30 lb in extension, and 126 (94%) had an ICLD ≤ 30 lb in flexion; and 165 (100%) had an ICLD ≤ 60 lb in extension, and 133 (99%) had an ICLD ≤ 60 lb in flexion. With a 0 mm difference between the medial and lateral stressed gaps, 103 (91%) of TKA had an ICLD ≤ 15 lb in extension, decreasing to 155 (88%) when the difference between the medial and lateral stressed extension gaps increased to ± 3 mm. In flexion, 47 (77%) had an ICLD ≤ 15 lb with a medial-lateral gap difference of 0 mm, increasing to 147 (84%) at ± 3 mm. Conclusion. This study found a strong relationship between intercompartmental loads and gap symmetry in extension and flexion measured with prostheses in situ. The results suggest that ICLD and medial-lateral gap difference provide similar assessment of soft-tissue balance in robotic arm-assisted TKA. Cite this article: Bone Jt Open 2021;2(11):974–980

Introduction. The purpose of this study was to determine if better outcomes occur with use of robotic-arm assistance by comparing consecutive series of non-robotic assisted (NR-TKA) and robotic-arm assisted (NR-TKA) total knee arthroplasties with the same implant. Methods. 80 NR-TKAs and then 101 RA-TKAs were performed consecutively. 70 knees in each group that had a minimum two-year follow-up were retrospectively reviewed. Range of motion, Knee Society (KS) scores, and forgotten joint scores (FJS) were compared using Mann-Whitney U tests. Tourniquets, used for all cases, had their inflation time recorded. Component realignment to minimize soft tissue releases was used in both groups with the goal to stay within a mechanical alignment of 3° of varus to 2° of valgus. The use of soft tissue releases for balance were compared. Results. There were no statistical differences in baseline characteristics including pre-operative Knee Society scores between cohorts. The two-year NR-TKA and RA-TKA median KS knee and functional scores were 99.0 and 90.0 and 100.0 and 100.0 respectively. Mann-Whitney U test indicated a statistically significant difference in KS-KS (p<.00001) and near statistically significant difference in KS-FS (p=0.075). The 10-point higher KS-FS is considered a minimal clinically important difference. The median FJS at two years for the NR-TKA was 61.5 and the RA-TKA was 75.0. Although not statistically significant (p=0.1556), the 13.5-point increase in the RA-TKA cohort also represents a minimal clinically important difference. RA-TKA patients had statistically significant 5° higher knee flexion (p<.00001). Desired post-operative coronal alignment was present in 92.9% of NR-TKAs and 94.3% of RA-TKAs. 28.6% more of the RA-TKA cases were able to be balanced without a soft tissue release. Median tourniquet time was only 3.9 minutes longer for the robotic-arm assisted cohort. Conclusion. This comparison study demonstrates potential benefits in use of robotic-arm assistance over manual instrumentation in TKA

Abstract. Introduction. Knee dislocations (KDs) are complex injuries which are often associated with damage to surrounding soft tissues or neurovascular structures. A classification system for these injuries should be simple and reproducible and allow communication among surgeons for surgical planning and outcome prediction. The aim of this study was to formulate a list of factors, prioritised by high-volume knee surgeons, that should be included in a KD classification system. Methods. A global panel of orthopaedic knee surgery specialists participated in a Delphi process. A list of factors to be included in a KD classification system was formulated by 91 orthopaedic surgeons, which was subsequently prioritised by 27 experts from 6 countries. The items were analysed to find factors that had at least 70% consensus for inclusion in a classification system. Results. The four factors that reached consensus agreement and thus deemed critical for inclusion in a classification system were vascular injuries (89%), common peroneal nerve injuries (78%), number of torn ligaments (78%), and open injuries (70%). Conclusion. The wide geographic distribution of participants provides diverse insight and makes the results of the study globally applicable. The most important factors to include in a classification system as determined by the Delphi technique were vascular injuries, common peroneal nerve injuries, number of torn ligaments, and open injuries. The Schenck anatomic classification system most accurately identifies these patient variables with the addition of open injuries. The authors propose to update the Schenck classification system with the inclusion of open injuries as an additional modifier

Abstract. Introduction. Historic MCL reconstruction techniques focused on the superficial MCL to restore valgus stability while overlooking tibial external rotation and the deep MCL. This study assessed the ability of a contemporary medial collateral ligament (MCL) reconstruction and a deep MCL (dMCL) reconstruction to restore rotational and valgus knee stability. Methods. Six pairs fresh-frozen cadaveric knee specimens with intact soft tissue were tested in four states: 1) intact 2) after sMCL and dMCL sectioning, 3) contemporary MCL reconstruction (LaPrade et al), and 4) dMCL reconstruction. In each state, four loading conditions were applied at varying flexion angles: 8Nm valgus torque, 5Nm tibial external rotation torque, 90N anterior drawer, and combined 90N anterior drawer plus 5Nm tibial external rotation torque. Results. Transection of the sMCL and dMCL resulted in increased laxity with valgus torque, external rotation torque, and combined anterior drawer plus external rotation. dMCL reconstruction restored external rotation stability to intact levels throughout all degrees of flexion but did not restore valgus stability at any flexion angle. Contemporary MCL reconstruction restored valgus and external rotation stability at 0° and 20° and valgus stability at 40°. In the combined anterior drawer plus tibial external rotation trial, the dMCL restored stability at 20° and improved stability between 40° and 90° flexion. Conversely, the contemporary MCL reconstruction did not restore stability at any degree of flexion. Conclusion. Deep MCL reconstruction restored rotational stability to the knee throughout range of motion but not valgus stability. The contemporary MCL reconstruction restored stability only near full extension

Abstract. INTRODUCTION. The anatomic distal femoral locking plate (DF-LCP) has simplified the management of supracondylar femoral fractures with stable knee prostheses. Osteoporosis and comminution seem manageable, but at times, the construct does not permit early mobilization. Considerable soft tissue stripping during open reduction and internal fixation (ORIF) may delay union. Biological plating offsets this disadvantage, minimizing morbidity. Materials. Thirty comminuted periprosthetic supracondylar fractures were operated from October 2010 to August 2016. Fifteen (group A) were treated with ORIF, and fifteen (group B) with closed (biological) plating using the anatomical DF-LCP. Post-operatively, standard rehabilitation protocol was followed in all, with hinged-knee-brace supported physiotherapy. Clinico-radiological follow-up was done at 3 months, 6 months, and then yearly (average duration, 30 months), and time to union, complications, failure rates and function were evaluated. Results. Average time to union was 4.5 months (range, 3–6 months) in group A, and 3.5 months (range, 2.5–5 months) in group B. Primary bone grafting was done in twelve patients (all group A). At final follow-up, all fractures had healed, and all (but two) patients were walking unsupported, with no pain or deformity, with average knee range of motion (ROM) of 90° (range, 55 to 100°). Two patients had superficial infection (group A), two had knee stiffness (group A), one had shortening of 1.5cm (group B) and one had valgus malalignment of 10 degrees (group B). Conclusion. Biological plating in comminuted supracondylar fractures about stable TKA prostheses is an excellent option, may obviate need for bone grafting, and reducing complications

Introduction. Infection following TKA can be a catastrophic complication that can cause significant pain, morbidity and jeopardize limb viability. The integrity of the soft tissue envelope is critical to successful treatment and infection control. While local tissue flaps can provide adequate coverage for most soft tissue defects around the knee, there are cases that require salvage using microvascular free tissue transfers. The purpose of this study is to evaluate the 1) rate of limb salvage; 2) infection control; and 3) clinical function following free flap coverage for salvage of the infected TKA. Materials and Methods. We retrospectively reviewed 23 microvascular free tissue transfers for management of soft tissue defects in infected TKA. There were 16 men and 7 women with a mean age of 61.2 years (range 39–81). The median number of procedures performed prior to soft tissue coverage was 5 (range 2–9) and all patients had failed at least one 2 stage reimplantation procedure. Clinical outcomes were measured using the Knee Society Scoring system for pain and function. The rate of limb salvage and infection control were recorded. Results. One patient was lost to follow up prior to 12 months. The remainder 22 patients were followed for a mean of 46 months (range 12–92 months). At latest follow up, 4 patients (18%) had undergone amputation for failure of treatment and persistent infection. For the remainder 18 patients, 11 patients (50%) have maintained a knee prosthesis in place while 7 patients had undergone resections for persistent infection but maintained their limbs (32%). Reoperations were common following coverage and reimplantation procedure. The median number of additional procedures was 2 (range 0–6). Clinical function was poor in patients who were reimplanted and retained a knee prosthesis following free flap coverage with a mean KSS score for pain and function of 44 (range 0–70) and 30 (range 0–65). All patients required an assistive device. Extensor mechanism problems and extensor lag requiring bracing were common following limb salvage and prosthesis reimplantation. Conclusions. Microvascular tissue transfer for management of infected TKA can be successful in limb salvage (81%) but clinical outcomes in salvaged limbs were poor. The data should be used to counsel patients when contemplating limb salvage in these severe, end-stage cases. For figures, tables, or references, please contact authors directly

Limb alignment in total knee arthroplasty (TKA) influences periarticular soft-tissue tension, biomechanics through knee flexion, and implant survival. Despite this, there is no uniform consensus on the optimal alignment technique for TKA. Neutral mechanical alignment facilitates knee flexion and symmetrical component wear but forces the limb into an unnatural position that alters native knee kinematics through the arc of knee flexion. Kinematic alignment aims to restore native limb alignment, but the safe ranges with this technique remain uncertain and the effects of this alignment technique on component survivorship remain unknown. Anatomical alignment aims to restore predisease limb alignment and knee geometry, but existing studies using this technique are based on cadaveric specimens or clinical trials with limited follow-up times. Functional alignment aims to restore the native plane and obliquity of the joint by manipulating implant positioning while limiting soft tissue releases, but the results of high-quality studies with long-term outcomes are still awaited. The drawbacks of existing studies on alignment include the use of surgical techniques with limited accuracy and reproducibility of achieving the planned alignment, poor correlation of intraoperative data to long-term functional outcomes and implant survivorship, and a paucity of studies on the safe ranges of limb alignment. Further studies on alignment in TKA should use surgical adjuncts (e.g. robotic technology) to help execute the planned alignment with improved accuracy, include intraoperative assessments of knee biomechanics and periarticular soft-tissue tension, and correlate alignment to long-term functional outcomes and survivorship

Aims. To compare patients undergoing total knee arthroplasty (TKA) with ≤ 80° range of movement (ROM) operated with a 2 mm increase in the flexion gap with matched non-stiff patients with at least 100° of preoperative ROM and balanced flexion and extension gaps. Methods. In a retrospective cohort study, 98 TKAs (91 patients) with a preoperative ROM of ≤ 80° were examined. Mean follow-up time was 53 months (24 to 112). All TKAs in stiff knees were performed with a 2 mm increased flexion gap. Data were compared to a matched control group of 98 TKAs (86 patients) with a mean follow-up of 43 months (24 to 89). Knees in the control group had a preoperative ROM of at least 100° and balanced flexion and extension gaps. In all stiff and non-stiff knees posterior stabilized (PS) TKAs with patellar resurfacing in combination with adequate soft tissue balancing were used. Results. Overall mean ROM in stiff knees increased preoperatively from 67° (0° to 80°) to 114° postoperatively (65° to 135°) (p < 0.001). Mean knee flexion improved from 82° (0° to 110°) to 115° (65° to 135°) and mean flexion contracture decreased from 14° (0° to 50°) to 1° (0° to 10°) (p < 0.001). The mean Knee Society Score (KSS) improved from 34 (0 to 71) to 88 (38 to 100) (p < 0.001) and the KSS Functional Score from 43 (0 to 70) to 86 (0 to 100). Seven knees (7%) required manipulations under anaesthesia (MUA) and none of the knees had flexion instability. The mean overall ROM in the control group improved from 117° (100° to 140°) to 123° (100° to 130°) (p < 0.001). Mean knee flexion improved from 119° (100° to 140°) to 123° (100° to 130°) (p < 0.001) and mean flexion contracture decreased from 2° (0° to 15°) to 0° (0° to 5°) (p < 0.001). None of the knees in the control group had flexion instability or required MUA. The mean KSS Knee Score improved from 48 (0 to 80) to 94 (79 to 100) (p < 0.001) and the KSS Functional Score from 52 (5 to 100) to 95 (60 to 100) (p < 0.001). Mean improvement in ROM (p < 0.001) and KSS Knee Score (p = 0.017) were greater in knees with preoperative stiffness compared with the control group, but the KSS Functional Score improvement was comparable (p = 0.885). Conclusion. TKA with a 2 mm increased flexion gap provided a significant improvement of ROM in knees with preoperative stiffness. While the improvement in ROM was greater, the absolute postoperative ROM was less than in matched non-stiff knees. PS TKA with patellar resurfacing and a 2 mm increased flexion gap, in combination with adequate soft tissue balancing, provides excellent ROM and knee function when stiffness of the knee had been present preoperatively. Cite this article: Bone Joint J 2020;102-B(4):426–433

Aims. The aims of this prospective study were to determine the effect of osteophyte excision on deformity correction and soft-tissue gap balance in varus knees undergoing computer-assisted total knee arthroplasty (TKA). Patients and Methods. Four-hundred twenty-five consecutive, cemented, cruciate-substituting TKAs were analysed. Pre-operative varus was calculated on long leg weight-bearing HKA film. Limb deformity in coronal (varus) and sagittal (flexion) planes, medial and lateral gap distances in maximum knee extension and 90° knee flexion and maximum knee flexion were recorded before and after excision of medial femoral and tibial osteophytes using computer navigation. Data was extracted and analysed to assess the effect of removal of osteophytes on the correction of deformity and soft tissue balance. Results. Before removal of any osteophytes or soft tissue releases, 138 out of 425 (32%) achieved correction of deformity (HKA 180+2°). In the remaining knees, after osteophyte removal 183 knees (43%) achieved correction of deformity. Overall, 75% knees achieved deformity correction after removal of osteophytes. For the remaining 25% knees, additional procedures (such as capsular release, semimembranosus release, reduction osteotomy) were needed for deformity correction. Conclusion. Three-fourths of all knees were aligned with no release or only removal of osteophytes. Excision of medial femoral and tibial osteophytes can be a useful, initial step towards achieving deformity correction and gap balance without having to resort to soft-tissue release during TKA in varus knees. This is useful information for surgeons to desist from any soft tissue releases till osteophytes have been meticulously excised. For figures, tables, or references, please contact authors directly

Abstract. Introduction. The postoperative inflammatory response may be implicated in the aetiology of patient dissatisfaction following Total Knee Arthroplasty. Robotic-arm assisted TKA has been associated with reduced bone and soft tissue trauma. The objective of this Randomised Controlled Trial was to compare the inflammatory response in conventional Jig-based versus robotic arm-assisted TKA and examine the relationship with patient reported outcome measures and functional outcomes. Methodology. 30 patients with knee osteoarthritis were randomised to either conventional or robotic-arm assisted TKA. Blood samples were collected for up to 28 days post-operatively and intraarticular drain samples at 6 and 24 hours, to ascertain the systemic and local inflammatory responses. The Spearman's correlation was utilised to evaluate the relationship with PROMs and functional outcomes. Results. Reduced IL-6 drain fluid levels were noted at 6 hours [798.54 vs. 5699.2, p=0.026] and 24 hours and IL-8 at 6 hours. Patients in the robotic group had lower pain scores on post-operative day 1, 2 and 7. PROM scores were comparable at 2 years. Statistically significant correlations were evident between all serum markers except IL-1b on the 7th postoperative day and self-reported pain; between drain IL-8 levels and self-reported pain; between drain IL-6, IL-8 and TNF-a levels (6-hours) and knee flexion and extension. Conclusion. Robotic-arm assisted TKA was associated with a reduced postoperative local and systemic inflammatory responses. A moderate correlation with self-reported pain, knee flexion and extension was also demonstrated. Longer-term data and further validation on a larger scale, will be key to developing the optimal TKA procedure

Abstract. Introduction. The incidence of significant acute chondral injuries with patella dislocation is around 10–15%. It is accepted that chondral procedures should only be performed in the presence of joint stability. Methodology. Patients were identified from surgeon/hospital logs. Patient demographics, lesion size and location, surgical procedure, patient reported outcome measures, post-operative MR imaging and complications were recorded. PROMs and patient satisfaction was obtained. Results. 20 knees (18 patients) were included. Mean age was 18.6 years (range; 11–39) and the mean follow-up was 16.6 months (range; 2–70). The defect locations were the lateral femoral condyle (9/20; 45%), patella (9/20; 45%), medial femoral condyle (1/20; 5%) and the trochlea (1/20; 5%). The mean defect size was 2.6cm2. Twelve knees were treated with cartilage fixation, 5 with microfracture and 3 with OATS. At follow up, the overall mean Lysholm score was 77.4 (± 17.1) with no chondral regenerative procedure being statistically superior. There was no difference in Lysholm scores between those patients having acute medial patellofemoral ligament reconstruction versus medial soft tissue plication (p=0.59). Five (25%) knees required re-operation (one arthroscopic arthrolysis; one patella chondroplasty; two removal of loose bodies; one implant adjustment). Overall 90% responded as being satisfied with surgery. Conclusion. Our aggressive pathway to identify and treat acute cartilage defects with early operative intervention and patella stabilisation has shown high rates of satisfaction and Lysholm scores with no major revisions. The full range of chondral restoration options should be considered by surgeons managing these patients

Aims. The primary aim of this study was to compare the postoperative systemic inflammatory response in conventional jig-based total knee arthroplasty (conventional TKA) versus robotic-arm assisted total knee arthroplasty (robotic TKA). Secondary aims were to compare the macroscopic soft tissue injury, femoral and tibial bone trauma, localized thermal response, and the accuracy of component positioning between the two treatment groups. Methods. This prospective randomized controlled trial included 30 patients with osteoarthritis of the knee undergoing conventional TKA versus robotic TKA. Predefined serum markers of inflammation and localized knee temperature were collected preoperatively and postoperatively at six hours, day 1, day 2, day 7, and day 28 following TKA. Blinded observers used the Macroscopic Soft Tissue Injury (MASTI) classification system to grade intraoperative periarticular soft tissue injury and bone trauma. Plain radiographs were used to assess the accuracy of achieving the planned postioning of the components in both groups. Results. Patients undergoing conventional TKA and robotic TKA had comparable changes in the postoperative systemic inflammatory and localized thermal response at six hours, day 1, day 2, and day 28 after surgery. Robotic TKA had significantly reduced levels of interleukin-6 (p < 0.001), tumour necrosis factor-α (p = 0.021), ESR (p = 0.001), CRP (p = 0.004), lactate dehydrogenase (p = 0.007), and creatine kinase (p = 0.004) at day 7 after surgery compared with conventional TKA. Robotic TKA was associated with significantly improved preservation of the periarticular soft tissue envelope (p < 0.001), and reduced femoral (p = 0.012) and tibial (p = 0.023) bone trauma compared with conventional TKA. Robotic TKA significantly improved the accuracy of achieving the planned limb alignment (p < 0.001), femoral component positioning (p < 0.001), and tibial component positioning (p < 0.001) compared with conventional TKA. Conclusion. Robotic TKA was associated with a transient reduction in the early (day 7) postoperative inflammatory response but there was no difference in the immediate (< 48 hours) or late (day 28) postoperative systemic inflammatory response compared with conventional TKA. Robotic TKA was associated with decreased iatrogenic periarticular soft tissue injury, reduced femoral and tibial bone trauma, and improved accuracy of component positioning compared with conventional TKA. Cite this article: Bone Joint J 2021;103-B(1):113–122

Aims. Inadvertent soft tissue damage caused by the oscillating saw during total knee arthroplasty (TKA) occurs when the sawblade passes beyond the bony boundaries into the soft tissue. The primary objective of this study is to assess the risk of inadvertent soft tissue damage during jig-based TKA by evaluating the excursion of the oscillating saw past the bony boundaries. The second objective is the investigation of the relation between this excursion and the surgeon’s experience level. Methods. A conventional jig-based TKA procedure with medial parapatellar approach was performed on 12 cadaveric knees by three experienced surgeons and three residents. During the proximal tibial resection, the motion of the oscillating saw with respect to the tibia was recorded. The distance of the outer point of this cutting portion to the edge of the bone was defined as the excursion of the oscillating saw. The excursion of the sawblade was evaluated in six zones containing the following structures: medial collateral ligament (MCL), posteromedial corner (PMC), iliotibial band (ITB), lateral collateral ligament (LCL), popliteus tendon (PopT), and neurovascular bundle (NVB). Results. The mean 75. th. percentile value of the excursion of all cases was mean 2.8 mm (SD 2.9) for the MCL zone, mean 4.8 mm (SD 5.9) for the PMC zone, mean 3.4 mm (SD 2.0) for the ITB zone, mean 6.3 mm (SD 4.8) for the LCL zone, mean 4.9 mm (SD 5.7) for the PopT zone, and mean 6.1 mm (SD 3.9) for the NVB zone. Experienced surgeons had a significantly lower excursion than residents. Conclusion. This study showed that the oscillating saw significantly passes the edge of the bone during the tibial resection in TKA, even in experienced hands. While reported neurovascular complications in TKA are rare, direct injury to the capsule and stabilizing structures around the knee is a consequence of the use of a hand-held oscillating saw when making the tibial cut. Cite this article: Bone Joint J 2020;102-B(10):1324–1330

Introduction. The success of total knee arthroplasty (TKA) necessitates precise osteotomies and soft tissue balancing to realign the lower extremity to a neutral mechanical axis. While technological advances have facilitated precise osteotomies, soft tissue balancing has traditionally relied mostly on surgeons’ subjective and variable tactile feedback. As soft tissue imbalance accounts for 35% of early TKA revisions in North America, we aimed to compare outcomes when TKA was balanced free-hand versus a sensor-guided balancing device (VERASENSE, OrthoSensor, Inc (Dania, FL)). Methods. In a randomized-controlled fashion, patients underwent primary TKA soft tissue balancing either free-hand or with VERASENSE (Orthosensor Inc, Dania FL) at our institution beginning January 2018. With VERASENSE, soft-tissue balancing is considered when the pressure difference between the medial and lateral knee compartments was less than 15 pounds. Data regarding patient-reported outcomes, knee range of motion (ROM), pain level, opioid consumption, inpatient ambulation distance, length of stay (LOS), and incidence of arthrofibrosis was collected and analyzed in a two-year minimum follow-up and target patient goal of 120 patients. Results. The study cohort thus far consists of 53 patients, average age 72.4 ± 8.8 years. Soft-tissue balance was conducted freehand in 23 patients and the VERASENSE was used in 30 patients. In the free-hand cohort, preoperative patient-reported outcomes for SF-12 Physical, Mental, WOMAC (pain, stiffness, function) parameters, and knee society function score (KSFS) were 39.3, 45.8, 47.7, 37.5, 48.1, and 50.0, respectively and post-operative at 3 months were 45.0, 53.0, 79.5, 72.5, 81.0, and 72.5, respectively; difference between preoperative and post-operative ROM was +8.4 degrees; average VAS pain score in the first 3 post-operative days was 2.9 ± 2.3; average opioid consumption was 100.7 ± 103.3 mg morphine equivalents; average inpatient ambulation per day was 267.9 ± 187.4 feet; average LOS was 2.3 days. In the VERASENSE cohort, patient reported outcomes for SF-12 Physical, Mental, WOMAC (pain, stiffness, function) parameters, and knee society function score (KSFS) were 38.2, 48.6, 40.1, 30.3, 40.0, and 48.7, respectively and post-operative at 3 months were 41.9, 47.6, 67.2, 59.7, 69.1, and 56.7; difference between preoperative and post-operative ROM was +3.9 degrees; average VAS pain score in the first 3 post-operative days was 2.9 ± 2.3; average opioid consumption was 105.8 ± 86.7 mg morphine equivalents; average inpatient ambulation was 384.6 ± 316.1 feet; average LOS was 2.1 days. There was no incidence of arthrofibrosis and subsequent manipulation under anesthesia in the trial. Conclusion. Short-term follow up of this randomized-controlled trial demonstrates equivalent patient-reported and clinical outcomes when soft-tissue balancing in TKA is performed free-hand versus utilization of VERASENSE, though we hypothesize a difference in the long-term