Ulnar shortening osteotomy (USO) is a procedure performed to alleviate ulnar sided wrist pain caused by ulnar impaction syndrome (UIS) and/or triangular fibrocartilage complex (TFCC) injury. Presently, non-union rates for ulnar shortening osteotomy is quoted to be 0–18% in the literature. However, there is a dearth of literature on the effect of site of osteotomy and plate placement on the rate of complications like a delayed union, symptomatic hardware and need for second surgery for hardware removal. In this study, we performed a multi-centered institutional review of ulnar shortening osteotomies performed, focusing on plate placement (volar vs. dorsal) and osteotomy site (distal vs. proximal) and determining if it plays a role in reducing complications. This study was a multi-centered retrospective chart review. All radiographs and charts for patients that have received USO for UIS or TFCC injury between 2013 and 2017 from hand and wrist fellowship-trained surgeons in Calgary, Alberta and Winnipeg, Manitoba were examined. Basic patient demographics including age, sex, past medical history, and smoking history were recorded. Postoperative complications such as delayed union, non-union, infection, chronic regional pain syndrome, hardware irritation requiring removal were evaluated with a two-year follow-up period. Osteotomy sites were analyzed based on the location in relation to the entire length of the ulna on forearm radiographs. Surgical techniques including volar vs. dorsal plating, oblique vs. transverse osteotomy cuts, and plate type were documented. Continuous variables of interest were summarized as mean or medians with standard deviation or inter-quartile range as appropriate. Differences in baseline characteristics were determined by t-test or one-way ANOVA for continuous variables and chi-square or Fischer exact test for dichotomous variables. All analyses were conducted using SPSS V24.0 (Chicago, IL, USA). All statistical tests were considered significant if p < 0.05. Between 2013–2017 there were 117 ulnar shortening osteotomies performed. The average age of patients was 46.2 ± 16.2, with 62.4% being female. The mean pre-operative ulnar variance was +3.89 ± 2.17 mm and post-operative ulnar variance was −1.90 ± 1.80 mm. 84.6% of the plates were placed on the volar aspect of the ulna and 14.5% were placed on the dorsal aspect. An oblique osteotomy was made 99.1% of the time. In measuring osteotomy placement, the average placement was made in the distal 1/3 of the ulna. Overall, there was a 40% complication rate. Hardware irritation requiring removal encompassed 23%, non-union 14%, and wound infection covered 0.8%. When comparing dorsal vs volar plating, there was no statistically significant difference for non-union or hardware removal. Similarly, in evaluating osteotomy level, there was no statistical difference between proximal vs distal osteotomy for non-union and hardware removal. In this multi-centered retrospective review of ulnar shortening osteotomies, we found that there was an overall complication rate of 40%. There was no statistically significant difference in complication rates between dorsal vs volar plate placement or proximal vs distal osteotomy sites. Further studies examining other potential risk factors in lowering the complication rate would be beneficial

The Bernese periacetabular osteotomy (PAO) is a well-established procedure in the management of symptomatic hip dysplasia. The associated Smith-Petersen exposure offers excellent visualization of the acetabulum and control of acetabular osteotomy and mobilization. The traditional exposure of the true pelvis involves osteotomy of the iliac wing in order to mobilize the sartorial and inguinal ligament insertion. However, full osteotomy of the iliac spine may necessitate screw fixation if a relatively large segment of bone is included. A known complication with screw fixation of the iliac wing osteotomy involves failure of fixation and screw back out. Moreover, the screw may be irritative to the patient even in the setting of adequate fixation. A larger osteotomy may also injure the lateral femoral cutaneous nerve as it travels near the anterior superior spine. To minimize the risk of these potential complications, a wafer osteotomy may be used to develop a sleeve of tissue involving the sartorial insertion. Markings may be made so that the curvilinear incision is centered about the anterior-superior iliac spine (ASIS). The sartorial sleeve also mobilizes the entirety of the lateral femoral cutaneous nerve medially as it runs and branches to varying degrees in a fatty tissue layer in the tensor-sartorius interval directly beneath the subcutaneous layer, thereby affording protection throughout the procedure. When the ASIS is first osteotomized as a several millimeter-thick mobile fragment and reflected, the sartorius attachment to the mobile fragment of the wafer osteotomy may be preserved. Furthermore, the wafer osteotomy may be re-fixed to the stable pelvis during closure with simple heavy suture fixation alone, avoiding screw insertion or associated removal. Because only a wafer or bone is taken during the spine osteotomy, more bone is available at the ASIS for fixation of the mobile fragment after repositioning. In this technical note, we describe the wafer osteotomy technique in further detail. For any figures or tables, please contact authors directly

Introduction. This study assessed outcomes of total knee joint replacements (TKJR) in patients who had undergone previous periarticular osteotomy compared with unicompartmental knee replacement (UKR). Establishing a difference in the results of total knee joint replacements following these operations may be an important consideration in the decision-making and patient counselling around osteotomy versus UKR for the management of single-compartment osteoarthritis. Method. Using data from the New Zealand Joint Registry, we identified 1,895 total knee joint replacements with prior osteotomy and 1,391 with prior UKR. Revision rates and patient-reported outcomes, as measured by the Oxford Knee Score (OKS), between these two groups were compared. Adjusted hazard ratios were also calculated to compare the groups. Results. The revision rate for total knee joint replacement following osteotomy was significantly lower than TKJR following UKR (0.88 per 100 component years versus 1.38 per 100 component years, respectively). Adjusted hazard ratio calculations found that those with TKJR with prior UKR had more than double the risk of requiring revision than those with prior osteotomy. Additionally, there was a statistically significant difference in the mean adjusted OKS scores between the two groups, with improved outcomes in the group with prior osteotomy. Conclusion. Our findings suggest that total knee joint replacement following periarticular osteotomy have a lower risk of revision and improved OKS when compared to those with prior UKR. Previous studies assessing New Zealand Joint Registry have not found a statistically significant difference between the two groups however, these results are no longer in keeping with more contemporary literature. Our study confirms the New Zealand population to be comparable with international studies with TKJR after osteotomy performing significantly better compared with prior UKR

Introduction. Osteotomy is a key step in distraction osteogenesis. Various techniques of osteotomy have been described with its own benefits and pitfalls. Percutaneous osteotomy using multiple drill holes is one of the most widely used osteotomy techniques. It still remains a challenge however to keep the drill holes aligned prior to the osteotomy. Moreover, the efficacy of percutaneous irrigation practice to keep the temperature low during drilling with this technique is also debatable. With an aim to overcome these challenges, we are introducing a device called the Double Barrel Drill Sleeve (DBDS) to perform percutaneous osteotomies. We attempted to compare this method to the conventional multiple drill holes technique using laboratory experiments and clinical data. Materials & Methods. DBDS has two adjacent parallel barrels that can fit 3.2 to 3.5 mm diameter drill bits. It has a guide member at the drilling end that can be inserted through a pre drilled hole at the near and far cortices of a bone. This provides a constant rotating point for drilling of holes through the barrels. An osteotomy simulation was performed to compare percutaneous drilling with DBDS vis-a-vis a conventional single drill sleeve (SDS) by qualified orthopaedic surgeons, mainly to assess the drilling patterns of both techniques. Percutaneous drilling was done on PVC pipes wrapped in thick sponge to simulate tubular bone with surrounding soft tissue. We also assessed the effect of indirect irrigation on temperature during drilling using the DBDS against a control group on a cadaveric bone model. Ultimately we reviewed our patients who had undergone osteotomy for distraction osteogenesis with DBDS and the conventional technique, and compared their outcomes. Results. Completion time for the osteotomy simulation in the DBDS group was significantly faster than the conventional drilling group; 74 seconds to 179 seconds. There was significantly less drilling deviation from the midpoint in the DBDS group as compared to the SDS group. Mean bone temperature during drilling with indirect irrigation using DBDS was significantly lower (32.6'C) compared to the control group (48.4'C). There was no significant difference in healing index between patients treated with DBDS and the conventional method. None of these patients developed non union. Conclusions. Percutaneous drilling with DBDS was quicker and more linear compared to the conventional method. Its double-barreled feature allows effective indirect irrigation during drilling. A comparable healing index in both of the techniques shows its clinical efficacy. These attributes make DBDS a usefull tool to overcome some of the pitfalls associated with the conventional multiple drill holes technique

Abstract. Introduction. Recurrent groin pain following periacetabular osteotomy (PAO) is a challenging problem. The purpose of our study was to evaluate the position and dynamics of the psoas tendon as a potential cause for recurrent groin pain following PAO. Methods. Patients with recurrent groin pain following PAO were identified from a single surgeon series. A total of 13 patients with 18 hips (4.7%) out of a 386 PAO, had recurrent groin pain. Muscle path of the psoas tendon was accurately represented using 3D models from CT data were created with Mimics software. A validated discrete element model using rigid body springs was used to predict psoas tendon movement during hip circumduction and walking. Results. Five out of the 18 hips did not show any malformations at the osteotomy site. Thirteen hips (72%) showed malformation secondary to callus at the superior pubic ramus. These were classified into: osteophytes at the osteotomy site, hypertrophic callus or non-union and malunion at the osteotomy. Mean minimal distance of the psoas tendon to osteophytes was found to be 6.24 mm (n=6) and to the osteotomy site was 14.18 mm (n=18). Conclusions. Recurrent groin pain after PAO needs a thorough assessment. One need to have a high suspicion of psoas issues as a cause. 3D CT scan may be necessary to identify causes related to healing of the pubic osteotomy. Dynamic ultrasound of the psoas psoas tendon may help in evaluating for psoas impingement as a cause of recurrent groin pain in these cases

Abstract. INTRODUCTION. Fracture neck of femur is aptly called as “the fracture of necessity” owing to the various factors responsible for its non-union. Pauwel's inter-trochantric valgus osteotomy is a useful approach to deal with such fractures. AIM. The aim of this study is to evaluate the functional outcome of valgus osteotomy in treatment of neglected and non-union fracture neck of femur using Harris Hip Scoring system (HHS). MATERIAL AND METHODS. This observational study included 25 patients of the age between 25 years and 50 years with more than 3 weeks since injury and the patients with failed primary fixation. Valgus osteotomy using120° double angled blade plate was done. The patients were followed up till one year. The patients' functional outcome was evaluated with pre-operative and post-operative Harris Hip Score (HHS) at 6 months and one year. RESULTS. Outcome was excellent in 14 patients (HHS>90), good in 8 patients (HHS between 80–90) and fair in one patient (HHS=75.6). Two patients ended up in non-union with blade cut out. The mean HHS at the end of one year was 89.18 + 7.822. The mean change in HHS values pre-operatively and one year post-operatively came out to be 69.58 + 20.032. CONCLUSION. We conclude that for the patients under 50 years of age with neglected fracture of the femoral neck, the Pauwel's osteotomy produces many good results

Introduction. Femoral-shortening osteotomy for the treatment of leg length discrepancy is demanding technique. Many surgical technique and orthopaedic devises have been suggested to perform this procedure. Herein, we describe modified femoral shortening osteotomy over a nail, using a percutaneous multiple drill-hole osteotomy technique. Materials and Methods. We operated on six patients with LLD. Mean femoral shortening was 4.2 cm. Osteotomy was performed using a multiple drill-hole technique, and bone was stabilized using an intramedullary nail. Post-operative clinical and radiological data were reported. Results. Shortening was achieved, with a final LLD of < 1 cm in all patients. All patients considered the lengths of the lower limbs to be equal. No special surgical skills or instrumentation were needed. Intraoperative and post-operative complications were not recorded. Conclusions. Percutaneous femoral-shortening osteotomy over a nail using multiple drill-hole osteotomy technique was effective and safe in treating LLD

Aim. Clavicular osteotomy was described as an adjunct to deltopectoral approach for improved exposure of the glenohumeral joint. This study aims to present contemporary outcomes and complications associated with the routine use of clavicular osteotomy by a single surgeon in a regional setting within New Zealand. Methods. A retrospective case series of patients who have undergone any shoulder arthroplasty for any indication between March 2017 to August 2022. This time period includes all patients who had clavicular osteotomy(OS) and patients over an equal time period prior to the routine use of osteotomy as a reference group (N-OS). Oxford Shoulder Score (OSS) and a Simple Shoulder Test (STT) were used to assess functional outcomes and were compared with the reported literature. Operative times and Complications were reviewed. Results. 66 patients were included in the study. 33 patients in the OS group and 33 in the N-OS group. No difference in age, sex, indications for operative intervention and the surgery provided was identified. No significant difference in operative time between groups (N-OS 121 minutes; OS 128 minutes). No clinically significant difference was identified in the OSS (N-OS; mean 38 vs OS 39) or the STT (N-OS 8.3 vs OS 9). The outcomes scores of both groups are in keeping with published literature. Two post operative clavicle fractures, one prominent surgical knot occurred in the OS that required further surgical intervention. Two cases of localized pain over the clavicle and one case of the prominent lateral clavicle were reported in the OS group. Two cases of localized pain over clavicle reported in the N-OS group. Conclusion. Use of clavicular osteotomy is not associated with inferior patient reported. The osteotomy introduces specific risks, however, the study provides evidence that these complications are infrequent and avoidable. Surgeons should feel confident in using this adjunct when exposure to the shoulder is difficult

Background. Periacetabular osteotomy (PAO) is an effective treatment method for early or mild osteoarthritis caused by developmental dysplasia of the hip. Since the procedure is performed from late eighties of the past century it is still a very demanding procedure performed only by high skilled surgeons in high volume orthopaedic centres. The idea was to develop a custom-made surgical tool to improve the accuracy of the two osteotomies of the iliac bone and help us to avoid inadvertent intraarticular osteotomy of the acetabulum. Methods. Firstly CT scans of pelvises of two cadavers were performed. The DICOM format files were up-loaded into EBS software (Ekliptik d.o.o., Ljubljana, Slovenia), application for preoperative planning, constructing and designing different templates, where the three-dimensional (3D) model of each pelvis was created. On the virtual pelvis models the PAO lines on each of four acetabuls were placed and virtual PAOs were performed [Fig. 1]. For the execution of the two iliac bone osteotomies the osteotome or saw guiding jigs were virtually created and exported in STL format in ProJet 3500 HDPlus printer which created custom made jigs made from VisiJet Crystal biocompatible plastic material (3D systems, Rock Hill, South Carolina, USA) for each of the four acetabula. The next step was the surgery on aforementioned cadavers. Extended Smith-Petrson approach was performed on each of four cadaveric hips and Bernese PAOs were performed using custom-made jigs. After performing the acetabular correction the cadavers were carefully dissected to study any possible posterior column damage or damage of the acetabular wall. None of them were damaged and the osteotomies were performed according to the virtual plan. Next step was the real procedure on 47-years old female patient with bilateral acetabular dysplasia. The procedure was executed on right side using the extended Smith-Peterson approach. Preoperatively native X-ray of both hips and the CT scan of pelvis were performed. According the CT scan (DICOM format) the virtual 3D model of the pelvis was created and virtual osteotomy lines were decided and production of the appropriate jig was manufactured in the same manner as for the cadavers [Fig. 2]. Preoperative and postoperative centre-edge (CE) angles were measured. Results. Preoperatively the patient had a Tönnis grade I osteoarthritis of the right hip. The preoperative CE angle was 19.1° and the postoperative CE angle is 36.7° [Fig. 3] which indicates good improvement in coverage of the femoral head. Patient had an uneventful postoperative course, with no neuro-vascular damage. The intraoperative blood loss was 250 ml and the patient was discharged from hospital on seventh postoperative day, walking with crutches loading 15 kg. Conclusion. Custom-made jig for iliac bone osteotomy in PAO procedures is a helpful tool, which improves accuracy of the osteotomy lines, safety of the patient and considerably reduces surgical time. We are planning to create also jigs for screw placement and the device to verify intraoperatively the level of PAO correction

Introduction: The mechanobiology and response of bone formation to strain under physiological loading is well established, however investigation into exceedingly soft scaffolds relative to cancellous bone is limited. In this study we designed and 3D printed mechanically-optimised low-stiffness implants, targeting specific strain ranges inducing bone formation and assessed their biological performance in a pre-clinical in vivo load-bearing tibial tuberosity advancement (TTA) model. The TTA model provides an attractive pre-clinical framework to investigate implant osseointegration within an uneven loading environment due to the dominating patellar tendon force. A knee finite element model from ovine CT data was developed to determine physiological target strains from simulated TTA surgery. We 3D printed low-stiffness Ti wedge osteotomy implants with homogeneous stiffness of 0.8 GPa (Ti1), 0.6 GPa (Ti2) and a locally-optimised design with a 0.3 GPa cortex and soft 0.1 GPa core (Ti3), for implantation in a 12-week ovine tibial advancement osteotomy (9mm). We quantitatively assessed bone fusion, bone area, mineral apposition rate and bone formation rate. Optimised Ti3 implants exhibited evenly high strains throughout, despite uneven wedge osteotomy loading. We demonstrated that higher strains above 3.75%, led to greater bone formation. Histomorphometry showed uniform bone ingrowthin optimised Ti3 compared to homogeneous designs (Ti1 and Ti2), and greater bone-implant contact. The greatest bone formation scores were seen in Ti3, followed by Ti2 and Ti1. Results from our study indicate lower stiffness and higher strain ranges than normally achieved in Ti scaffolds stimulate early bone formation. By accounting for loading environments through rational design, implants can be optimised to improve uniform osseointegration. Design and 3D printing of exceedingly soft titanium orthopaedic implants enhance strain induced bone formation and have significant importance in future implant design for knee, hip arthroplasty and treatment of large load-bearing bone defects

Introduction. Derotation osteotomies are commonly performed in paediatric orthopaedic and limb reconstruction practice. The purpose of this study was to determine whether the use of a digital inclinometer significantly improves the accuracy in attaining the desired correction. Materials & Methods. We designed an electronic survey regarding derotation femoral osteotomy (DFO) including methods of intra-operative angular correction assessment and acceptable margins of error for correction. This was distributed to 28 paediatric orthopaedic surgeons in our region. A DFO model was created, using an anatomic sawbone with foam covering. 8 orthopaedic surgeons each performed two 30-degree DFOs, one using K-wires and visual estimation (VE), and the other using a Digital Inclinometer (DI). Two radiologists reported pre and post procedure rotational profile CT scans to assess the achieved rotational correction. Results. There was a 68% response rate to the survey. The most popular methods of estimating intra-operative correction were reported to be K-wires and rotation marks on bone. The majority of respondents reported that a 6–10 degree margin of error was acceptable for a 30-degree derotation. This was therefore set as the upper limit for acceptable error margin in the simulation study. The mean error in rotation in the VE group of simulated DFO was 19.7 degrees, with error>5 degrees and error>10 degrees in 7 (88%) and 6 (75%) cases respectively. Mean error in DI group was 3.1 degrees, with error>5 degrees in 1 case (13%). Conclusions. Our results show that the compared to conventional techniques, the use of an inclinometer significantly improves the accuracy of femoral de-rotation and significantly reduces the incidence of unacceptable errors in correction. We would suggest that digital inclinometers be used to assess intra-operative correction during derotation osteotomies

The aim of this study was to determine the long term 20 year survival and outcomes of high tibial osteotomy (HTO). 100 consecutive subjects underwent HTO under the care of a single surgeon between 2000 and 2002, consented to participation in a prospective study and completed preoperative WOMAC scores. Subjects were reviewed at 10 years, and again at a minimum of 20 years after surgery. PROMS included further surgery, WOMAC scores, Oxford Knee Score (OHS), KOOS, and EQ-5D, and satisfaction with surgery. 20 year survival was assessed with Kaplan-Meir analysis, and failure defined as proceeding to subsequent knee arthroplasty. The mean age at HTO was 50 years (range 26-66), and 72% were males. The 5, 10, and 20 year survival of the HTO was 88%, 76%, 43% respectively. On multiple regression analysis HTO failure was associated with poor preoperative WOMAC score of 45 or less (HR 3.2, 95% CI 1.7-6.0, p=0.001), age at surgery of 55 or more (HR 2.3, 95% CI 1.3-4.0, p=0.004), and obesity (HR 1.9, 95% CI 1.1-3.4, p=0.023). In patients who met all criteria of preoperative WOMAC score of 45 or less, age <55 years and body mass index of <30 HTO survival was 100%, 94%, and 59% at 5, 10 and 20 years respectively. Of those who had not proceeded to TKA the mean Oxford Score was 40, KOOS Pain score was 91 and KOOS function score was 97. 97% reported they were satisfied with the surgery and 88% would have the same surgery again under the same circumstances. At 20 years after HTO 43% had not proceeded to knee arthroplasty, and were continuing to demonstrate high subjective scores and satisfaction with surgery. HTO survival was higher in those under 55 years, with BMI <30 and baseline WOMAC score of >45 at 59% HTO survival over 20 years. HTO may be considered a viable procedure to delay premature knee arthroplasty in carefully selected subjects

Abstract. Extended Trochanteric Osteotomy (ETO) improves surgical exposure and aids femoral stem and bone cement removal in Revision Total Hip Replacement (RTHR) surgery. The aim of this study was to identify healing rates and complications of ETO in RTHR. Methods. From 2012 to 2019 we identified patients who underwent ETO for RTHR. Data collected demographics, BMI, diabetes, anticoagulants, indication for ETO, surgical approach, length of ETO and complications. Descriptive analysis of patient demographics, multiple linear regression analysis was performed to assess ETO complications. Results. There were 63 patients with an average age of 69 years. Indications for ETO were aseptic loosening (30), infection (15), periprosthetic fracture (9), recurrent dislocation (5), broken implant (4). There were 44 cemented and 19 uncemented femoral stem that underwent ETO. Average time from index surgery was 12 years (less than a year to 38 years). All procedures were through posterolateral approach and all ETO were stabilised with cables. Average length of ETO was 12.5cm. BMI varied from 18 to 37. There were 5 diabetics and 16 on anticoagulants. All but one ETO went on to unite. Other complications included infection, dislocations, lateral thigh pain and significant limp. Discussion. Fixation of ETO can be with either wires or cables or plate with cables/screws. Advantages of cables are no irritation over greater trochanter, no disruption of gluteus medius/vastus lateralis continuity, reproducible tension in cables and use of torque limiter minimises loss of tension in cables

Olecranon Osteotomy is a common approach used in the management of intraarticular distal humerus fractures. Significant complication rates have been associated with this procedure, including non-union rates of 0–13% and implant removal rates between 12–86%. This study is a multicentre retrospective study involving the largest cohort of olecranon osteotomies in the literature, examining implant fixation types, removal rates and associated complications. Patients were identified between 2007 and 2017 (minimum one year follow-up) via Canadian Classification of Health Interventions (CCI) coding and ICD9/10 codes by our health region's data information service. CCI intervention codes were used to identify patients who underwent surgery for their fracture with an olecranon osteotomy. Reasons for implant removal were identified from a chart review. Our primary outcome was implant removal rates. Categorical data was assessed using Chi square test and Fischer's Exact test. Ninety-nine patients were identified to have undergone an olecranon osteotomy for treatment of a distal humerus fracture. Twenty patients had their osteotomy fixed with a plate and screws and 67 patients were fixed with a tension band wire. Eleven patients underwent “screw fixation”, consisting of a single screw with or without the addition of a wire. One patient had placement of a cable-pin system. Of patients who underwent olecranon osteotomy fixation, 34.3% required implant removal. Removal rates were: 28/67 for TBW (41.8%), 6/20 plates (30%), 0/1 cable-pin and 0/11 for osteotomies fixed with screw fixation. Screw fixation was removed less frequently than TBW p<.006. TBW were more commonly removed than all other fixation types p<.043. Screws were less commonly removed than all other fixation types p<.015. TBW were more likely to be removed for implant irritation than plates, p<.007, and all other implants p<.007. The average time to removal was 361 days (80–1503 days). A second surgeon was the surgeon responsible for the removal in 10/34 cases (29%). TBWs requiring removal were further off the olecranon tip than those not removed p=.006. TBWs were associated with an OR of 3.29 (CI 1.10–9.84) for implant removal if implanted further than 1mm off bone. Nonunion of the osteotomy occurred in three out of 99 patients (3%). K-wires through the anterior ulnar cortex did not result in decreased need for TBW removal. There was no relation between plate prominence and the need for implant removal. There was no association between age and implant removal. The implant removal rate was 34% overall. Single screw fixation was the best option for osteotomy fixation, as 0/11 required hardware removal, which was statistically less frequent than TBW at 28/67. Screw fixation was removed less frequently than TBW and screw fixation was less commonly removed than all other fixation types. Only 6/20 (30%) plates required removal, which is lower than previously published rates. Overall, TBW were more commonly removed than all other fixation types and this was also the case if hardware irritation was used as the indication for removal. Nonunion rates of olecranon osteotomy were 3%

This study aimed to examine the effect of high tibial osteotomy (HTO) on the ankle and subtalar joints via analysis of static radiographic alignment. We hypothesised that surgical alteration of the alignment of the proximal tibia would result in compensatory distal changes. 35 patients recruited as part of the wider Biomechanics and Bioengineering Centre Versus Arthritis HTO study between 2011 and 2018 had pre- and postoperative full-length weightbearing radiographs taken of their lower limbs. In addition to standard alignment measures of the limb and knee (mechanical tibiofemoral angle, Mikulicz point, medial proximal tibial angle), additional measures were taken of the ankle/subtalar joints (lateral distal tibial angle, ground-talus angle, joint line convergence angle of the ankle) as well as a novel measure of stance width. Results were compared using a paired T-test and Pearson's correlation coefficient. Following HTO, there was a significant (5.4°) change in subtalar alignment. Ground-talus angle appeared related both to the level of malalignment preoperatively and the magnitude of the alignment change caused by the HTO surgery; suggesting subtalar positioning as a key adaptive mechanism. In addition to compensatory changes within the subtalar joints, the patients on average had a 31% wider stance following HTO. These two mechanisms do not appear to be correlated but the morphology of the tibial plafond may influence which compensatory mechanisms are employed by different subgroups of HTO patients. These findings are of vital importance in clinical practice both to anticipate potential changes to the ankle and subtalar joints following HTO but it could also open up wider indications for HTO in the treatment of ankle malalignment and osteoarthritis

The anterior portion of the anatomical neck is used as a reference for the osteotomy in shoulder arthroplasty. Resection at this level is thought to remove a segment of a sphere which can accurately be replaced with a prosthetic implant. The objective of the study was to analyse the cartilage/metaphyseal interface relative to an ideal osteotomy plane to define points of reference the may recover retroversion accurately. Data were collected from 24 humeri using a novel technique, combining data acquired using a Microscribe digitiser and surface laser scanner. Rhinocerus NURBS modelling software was used to analyse the Cartilage/metaphyseal interface. The retroversion angle was calculated for the normal geometry and for the standard osteotomy along the anterior cartilage/metaphyseal interface. An ideal osteotomy plane was then created for each specimen and the perpendicular distance from the cartilage/metaphyseal interface was determined, identifying points of least deviation. The reference points were used to simulate a new osteotomy for which retroversion was calculated. Paired t-tests were used to compare the novel osteotomy and traditional osteotomy to the normal geometry. The mean retroversion for the normal geometry was 18.5±9.0 degrees. The mean retroversion for the traditional osteotomy technique was 29.5±10.7 degrees, significantly different from the original (p< 0.001). The mean retroversion using the novel osteotomy was 18.9±8.9 degrees and similar to the normal geometry (p=0.528). The traditional osteotomy resulted in a mean increase in retroversion of 38%. The increase in version may result in eccentric load on the glenoid, an alteration to the rotator cuff balance and poor clinical outcome. The novel osteotomy based on points identified around the cartilage/metaphyseal interface that deviated least from an ideal osteotomy plane resulted in more accurate recovery of head geometry. The novel technique may improve clinical outcome. Further investigation is warranted

Higher levels of socioeconomic deprivation have been associated with worse health outcomes. The influence of socioeconomic deprivation on patients undergoing periacetabular osteotomy (PAO) has not previously been investigated. A total of 217 patients (171 female, 46 male; median age 23.4 years) who underwent PAO by a single surgeon were identified. Patients were categorised into three groups according to their New Zealand Deprivation (NZDep) Index: minimal deprivation (NZDep Index 1–3, n=89), moderate deprivation (NZDep Index 4–6, n=94), and maximal deprivation (NZDep Index 7–10, n=34). The three groups were compared with respect to baseline variables, surgical details, complications, and pre-operative and two-year post-operative functional scores (including International Hip Outcome Tool (iHOT-12), EQ-5D quality of life score, and University of California Los Angeles (UCLA) activity score). Multivariate regression was undertaken to assess for the effect of NZDep Index on patient outcomes. Patients in the maximal deprivation group were more likely to be Māori (p<0.001) and have surgery in a public rather than a private hospital (p=0.004), while the minimal deprivation group demonstrated a lower BMI (p=0.005). There were otherwise no other significant differences in baseline variables, surgical details, complications, nor pre-operative or two-year post-operative functional scores between the three groups (all p>0.05). Multivariate analysis identified a higher NZDep Index to be independently predictive of a lower pre-operative UCLA activity score (p=0.014) and a higher two-year iHOT-12 score (p<0.001). Our results demonstrate an inequality in access to PAO, with patients exposed to higher levels of socioeconomic deprivation under-represented in our study population. When provided access to PAO, these vulnerable patients achieve significant functional improvement at least as great as patients with less socioeconomic deprivation. Initiatives to improve access to hip preservation care in socioeconomically deprived populations appear warranted

Introduction. Torsional malalignment syndrome (TMS) is a unique combination of rotational deformities in the lower limb, often leading to severe patellofemoral joint pain and disability. Surgical management of this condition usually consists of two osteotomies in each affected limb, with simultaneous correction of both femoral anteversion and external tibial torsion. However, we believe that a single supratubercular osteotomy followed by tibial derotation with the Taylor Spatial Frame (TSF) can be used to provide a significant improvement in both appearance and function. Materials and Methods. This is a retrospective case analysis in which we will be reviewing 16 osteotomies performed by one surgeon between 2006 and 2017. The study includes 11 patients with a mean age of 16.7 ± 0.8 years. Pre and post-operatively, patients were fully evaluated through history and physical examination, and CT rotational profiling. Statistical analyses were performed in order to determine whether or not any observed clinical or cosmetic improvements were statistically significant. Results. The results show significant improvements in scores reported on post-operative functional assessment, with mean Oxford Knee Score (OKS) increasing by 18.3 and mean Kujala Anterior Knee Pain Scale (AKPS) also increasing by 31.4. In addition to this, post-operative clinical assessment showed a reduced thigh-foot angle (TFA) in all cases, by a mean value of 31.9o. The angle of the transmalleolar axis (TMA) was successfully reduced in 14/16 cases, by a mean value of 8.6o. Statistical analysis showed all of these results to be statistically significant where p<0.05. Conclusions. The results show that supratubercular osteotomy, followed by gradual correction with TSF, can be used to provide a significant improvement in both appearance and function for patients suffering from TMS

The influence of patient age on functional outcomes after periacetabular osteotomy (PAO) for acetabular dysplasia remains unclear, with previous studies utilising scores developed for older, arthritic patients. The purpose of this study is to assess the influence of patient age on International Hip Outcome Tool (iHOT-12) scores, two years after PAO. Eighty-six patients (72 female, 14 male; mean age 26.9 years) who underwent PAO by a single surgeon and had completed a minimum of two years follow up were identified. Patients were categorised into three groups according to age at the time of surgery: adolescent (11–20 years; n=29), young adult (21–30 years; n=29), and mature (≥31 years; n=28). The three groups were compared with respect to baseline variables and functional outcomes (iHOT-12, EQ-5D quality of life score, University of California Los Angeles (UCLA) activity score, pain visual analogue score (VAS)). Multivariate regression was undertaken to assess for independent predictors of two-year iHOT-12 score. The adolescent group demonstrated a lower BMI (p=0.004) while the mature group had a greater American Society of Anaesthesiology (ASA) score (p=0.049). There were otherwise no significant differences in baseline variables between the three groups (all p>0.05). The three groups demonstrated significant post-operative improvements across all functional outcome measures. There were no significant differences in two-year iHOT-12, EQ-5D, UCLA score or pain VAS between the three groups (all p>0.05). Regression modelling found that patient age at the time of surgery did not have an independent effect on two-year iHOT-12 score (p=0.878). We found that patient age at the time of surgery did not influence functional outcomes two years after PAO. Our results suggest that patient age should not be considered in isolation as an indication or contraindication for PAO

An osteochondral defect greater than 3cm in diameter and 1cm in depth is best managed by an osteochondral allograft. If there is an associated knee deformity, then an osteotomy is performed. In our series of osteochondral allografts for large post-traumatic knee defects realignment osteotomy is performed about 60% of the time in order to off-load the transplant. To correct varus we realign the proximal tibia with an opening wedge osteotomy. To correct valgus, we realign the distal femur with a closing wedge osteotomy. Our results with osteochondral allografts for the large osteochondral defects of the knee both femur and tibia, have been excellent in 85% of patients at an average follow-up of 10 years. The Kaplan-Meier survivorship at 15 years is 72%. At an average follow-up of 22 years in 58 patients with distal femoral osteochondral allograft, 13 have been revised (22%). The 15-year survivorship was 84%. Retrieval studies of 24 fresh osteochondral grafts obtained at graft revision or conversion total knee replacement at an average of 12 years (5 – 25) revealed the following. In the areas where the graft was still intact, the cartilage was of normal thickness and architecture. Matrix staining was normal except in the superficial and upper mid zones. Chondrocytes were mostly viable but there was chondrocyte clusters and loss of chondrocyte polarity. Host bone had extended to the calcified cartilage but variable remnants of dead bone surrounded by live bone persisted. With a stable osseous base the hyaline cartilage portion of the graft can survive for up to 25 years