There are a number of progressive conditions that afflict the hip and result in degenerative arthritis. Along the path of progression of the disease and prior to the development of arthritis, some of these conditions may be treatable by joint preservation procedures. Periacetabular osteotomy for developmental dysplasia of the hip (DDH), femoroacetabular osteoplasty for femoroacetabular impingement (FAI), and a variety of surgical procedures for management of early osteonecrosis of the femoral head are some examples of joint preservation of the hip. DDH is characterised by abnormal development of the acetabulum and the proximal femur that leads to suboptimal contact of the articular surfaces and the resultant increase in joint reaction forces. FAI is a condition characterised by an abnormal contact between the femoral neck and the acetabular rim. FAI is believed to exist when a triad of signs (abnormal alpha angle, labral tear, and chondral lesion) can be identified. The question that remains is whether joint preservation procedures are able to avert the need for arthroplasty or just an intervention along the natural path of progression of the hip disease. There is an interesting study that followed 628 infants born in a Navajo reservation, including 8 infants with severe dysplasia, for 35 years. None of the children with DDH had surgical treatment and all had developed severe arthritis in the interim. The latter study and a few other natural history studies have shown that the lack of administration of surgical treatment to patients with symptomatic DDH results in accelerated arthritis. The situation is not so clear with FAI. Some believe that FAI is a pre-arthritic condition and surgical treatment is only effective in addressing the symptoms and does not delay or defer an arthroplasty. While others believe that restoration of the normal mechanical environment to the hip of FAI patients, by removing the abnormal contact and repair of the labrum, is likely to change the natural history of the disease and at minimum delay the need for an arthroplasty. There is a need for natural history studies or case series to settle the latter controversy

Hip joint preservation remains a preferred treatment option for hips with mechanically correctable pathologies prior to the development of significant secondary arthrosis. The pathologies most amenable to joint preservation are hip dysplasia and femoroacetabular impingement. These pathologies sometimes overlap. Untreated acetabular dysplasia of modest severity always leads to arthrosis if uncorrected. Acetabular dysplasia is best treated by periacetabular osteotomy, usually combined with arthrotomy for management of labral pathology and associated cam-impingement if present. Pre-operative variables associated with the best long-term outcomes include less secondary arthrosis, younger age, and concentric articular surfaces. The earlier PAO series show 20 year survivorship of 81% and 65% in Tonnis Grade 0 and 1 hips. Femoroacetabular impingement has become progressively recognised as perhaps the most common cause of secondary arthrosis. The etiology of impingement is multifactorial and includes both genetic factors and stresses experienced by the hip prior to cessation of growth. Cam impingement can be quantified by the alpha angle as measured on plain radiographs and radial MR sequences. Cam impingement can be treated by arthroscopic or open femoral head-neck osteochondroplasty. As with hip dysplasia, prognosis following treatment is correlated with the severity of pre-operative secondary arthrosis but unfortunately impinging hips more commonly have some degree of arthrosis pre-operatively whereas dysplastic hips can become symptomatic with instability in the absence of arthrosis. The scientific basis for the treatment of pincer impingement is less strong. Unlike cam impingement and hip dysplasia, pincer impingement pathology in the absence of coxa profunda has not been correlated with arthrosis and so rim trimming with labral refixation is probably performed more often than is clinically indicated. Overall, joint preserving surgery remains the preferred treatment for hips with mechanically correctable problems prior to the development of significant secondary arthrosis

Hip joint preservation remains a preferred treatment option for hips with mechanically correctable pathologies prior to the development of significant secondary arthrosis. The pathologies most amenable to joint preservation are hip dysplasia and femoroacetabular impingement. These pathologies sometimes overlap. Untreated acetabular dysplasia of modest severity always leads to arthrosis if uncorrected. Acetabular dysplasia is best treated by periacetabular osteotomy, usually combined with arthrotomy for management of labral pathology and associated cam-impingement if present. Preoperative variables associated with the best long-term outcomes include less secondary arthrosis, younger age, and concentric articular surfaces. Femoroacetabular impingement has become progressively recognised as perhaps the most common cause of secondary arthrosis. The etiology of impingement is multifactorial and includes both genetic factors and stresses experienced by the hip prior to cessation of growth. Cam impingement can be quantified by the alpha angle as measured on plain radiographs and radial MR sequences. Cam impingement can be treated by arthroscopic or open femoral head-neck osteochondroplasty. As with hip dysplasia, prognosis following treatment is correlated with the severity of preoperative secondary arthrosis but unfortunately impinging hips more commonly have some degree of arthrosis preop whereas dysplastic hips can become symptomic with instability in the absence of arthrosis. The scientific basis for the treatment of pincer impingement is less strong. Unlike cam impingement and hip dysplasia, pincer impingement pathology in the absence of coxa profunda has not been correlated with arthrosis and so rim trimming with labral refixation is probably performed more often than is clinically indicated. Overall, joint preserving surgery remains the preferred treatment for hips with mechanically correctible problems prior to the development of significant secondary arthrosis

Over the past fifteen years hip preservation surgery has rapidly evolved. Improved understanding of the pathomechanics and associated intra-articular degeneration of both hip instability and femoroacetabular impingement have led to improved surgical indications, refined surgical techniques and more effective joint preservation surgical procedures. The periacetabular osteotomy (PAO) was initially introduced by Ganz and colleagues and has become the preferred treatment in North America for pre-arthritic, symptomatic acetabular dysplasia. Both hip arthroscopy and safe surgical dislocation of the hip have been popularised for the treatment of symptomatic femoroacetabular impingement disorders. Hip arthroscopy is effective for focal and\or accessible impingement lesions while the surgical dislocation approach is reserved for nonfocal disease patterns as seen in complex FAI, and residual Perthes and SCFE deformities. Femoroacetabular impingement from major acetabular retroversion can be managed with the PAO if there is coexistent posterosuperior acetabular insufficiency. Short- to mid-term results of these procedures are generally good to excellent for most patients and the complication rates associated with these procedures are very acceptable. Long-term outcomes are best known for the PAO. Several recent studies have documented survivorship rates of 65–90% at 10–20-year follow-up. Certain factors are associated with long-term success including minimal pre-operative radiographic OA, early symptoms, accurate acetabular correction, and younger age. These data strongly suggest that the PAO can defer THA to an older age for most patients while completely avoiding arthroplasty may only be possible in select patients with excellent congruency, no secondary OA and an ideal surgical correction

Surgical invention to preserve the native hip joint remains a preferred treatment option for hips in young patients with mechanically correctable pathologies prior to the development of significant secondary arthrosis. The two most common pathologies most amenable to joint preservation are hip dysplasia and femoroacetabular impingement. These pathologies sometimes overlap. Untreated acetabular dysplasia of modest severity, if left uncorrected, always leads to arthrosis. Acetabular dysplasia is best treated by periacetabular osteotomy, usually combined with arthrotomy for management of labral pathology and associated cam-impingement, if present. Correction of deformities on the femoral side is now less common and reserved for only the more severe combined femoral and acetabular dysplasias or the rare isolated femoral dysplasia. Pre-operative variables associated with the best long-term outcomes include less secondary arthrosis, younger age, and concentric articular surfaces. Femoroacetabular impingement has become progressively recognised as perhaps the most common cause of secondary arthrosis. The etiology of impingement is multifactorial and includes both genetic factors and stresses experienced by the hip prior to cessation of growth. Cam impingement can be quantified by the alpha angle as measured on plain radiographs and radial MR sequences. Further, significant cam impingement is clearly associated with the development of osteoarthrosis. Treatment can be performed either by arthroscopic or open femoral head-neck osteochondroplasty. As with hip dysplasia, prognosis following treatment is correlated with the severity of pre-operative secondary arthrosis but unfortunately impinging hips more commonly have some degree of arthrosis pre-op whereas dysplastic hips can become symptomatic with the onset of instability in the absence of significant secondary arthrosis. The scientific basis for the treatment of pincer impingement is less strong. Unlike cam impingement and hip dysplasia, pincer impingement pathology in the absence of coxa profunda has not been correlated with arthrosis and so rim trimming with labral refixation is probably performed more often than is clinically indicated. Similarly, caution should be exercised when considering rim-trimming for protrusion since high central contact pressures due to an enlarged acetabular notch are not corrected by rim trimming. Overall, joint preserving surgery remains the preferred treatment for hips with mechanically correctable problems prior to the development of significant secondary arthrosis

Although cartilage repair has been around since the time of open Pridie drilling, clinical outcomes for newer techniques such as arthroscopic debridement, microfracture (MFX), osteochondral autograft transfers (OATS), osteochondral allograft transplantation and Autologous Chondrocyte Implantation (ACI) are still finding their place in treating injured knees.

Early mechanical symptoms are best managed by a gentle arthroscopic debridement of loose articular flaps. This allows the surgeon to assess the defect size, location in the tibio-femoral or patellofemoral joint, status of the cartilage overall and patients response to the intervention. If the symptom improvement is not satisfactory to the patient, after assessing background factors that will influence the results of a cartilage repair procedure, (alignment of the patellofemoral joint or axial alignment, ligament stability and status of the meniscus), the surgeon can choose the best procedure for that individual based on the expected outcomes of the various cartilage repair techniques while addressing the background factors. As all the techniques have failures and informed discussion with the patient prior to performing the procedure is critical in avoiding disappointment for the patient and the surgeon.

The repair technique used should incorporate considerations of the defect size, location, and the patient age, activity level, expectations and ability to comply with the longer rehabilitation needed for biological procedures as compared to prosthetic implants.

The majority of patients who develop hip arthritis have a mechanical abnormality of the joint. The structural abnormalities range from instability (DDH) to impingement. Impingement leads to osteoarthritis by chronic damage to the acetabular labrum and adjacent cartilage.

In situations of endstage secondary DJD, hip arthroplasty is the most reliable treatment choice. In young patients with viable articular cartilage, joint salvage is indicated. Treatment should be directed at resolving the structural abnormalities that create the impingement.

Femoral abnormalities corrected by osteotomy or increased head-neck offset by chondro-osteoplasty creating a satisfactory head-neck offset. This can safely be done via anterior surgical dislocation or arthroscopically. The acetabular-labral lesions can be debrided and/or repaired. Acetabular abnormalities should be corrected by “reverse” PAO in those with acetabular retroversion or anterior acetabular debridement in those with satisfactory posterior coverage and a damaged anterior rim.

Often combinations of the above are indicated.

Cartilage is known to have limited intrinsic repair capabilities and cartilage defects can progress to osteoarthritis (OA). OA is a major economic burden of the 21st century, being among the leading causes of disability. The risk of disability from knee OA is as great as that derived from cardiovascular disease; a fact that becomes even more concerning when considering that even isolated cartilage defects can cause pain and disability comparable to that of severe OA.

Several cartilage repair procedures are in current clinical application, including microfracture, osteochondral autograft transfer, osteochondral allograft transplantation, and autologous chondrocyte implantation (ACI). Given the economic challenges facing our health care system, it appears prudent to choose procedures that provide the most durable long-term outcome. Comparatively few studies have examined long-term outcomes, an important factor when considering the substantial differences in cost and morbidity among the various treatment options.

This study reviews the clinical outcomes of autologous chondrocyte implantation at a minimum of 10 years after treatment of chondral defects of the knee. Mean age at surgery was 36 ± 9 years; mean defect size measured 8.4 ± 5.5cm2. Outcome scores were prospectively collected pre- and postoperatively at the last follow up. We further analyzed potential factors contributing to failure in hopes of refining the indications for this procedure.

Conclusions: ACI provided durable outcomes with a survivorship of 71% at 10 years and improved function in 75% of patients with symptomatic cartilage defects of the knee at a minimum of 10 years after surgery. A history of prior marrow stimulation as well as the treatment of very large defects was associated with an increased risk of failure.

Purpose

While changes in lower limb alignment and pelvic inclination after total hip arthroplasty (THA) using certain surgical approaches have been studied, the effect of preserving the joint capsule is still unclear. We retrospectively investigated changes in lower limb alignment, length and pelvic inclination before and after surgery, and the risk of postoperative dislocation in patients who underwent capsule preserving THA using the anterolateral-supine (ALS) approach.

Surgical treatment options for Femoroacetabular impingement (FAI) includes both surgical dislocation and hip arthroscopy techniques. The primary aim of this study was to evaluate and compare the survivorship of arthroscopies (scope) and surgical dislocations (SD) at minimum 5-year follow-up. The secondary aim was to describe differences in functional outcomes between the 2 groups. This was a retrospective, single surgeon, consecutive, case-series from a large tertiary care centre. We evaluated all surgeries that were performed between 2005 and 2011. Our institutional database was queried for any patient undergoing surgery for FAI (pincer (n=23), cam (n=306), or mixed (n=103) types). Patients with childhood pathologies i.e. Legg Calve Perthes and slipped capital femoral epiphysis were excluded. This resulted in 221 hips (169 males, 52 females) who underwent either SD (94, 42.5%) or scope (127, 57.5%). A manual chart review was completed to identify patients who sustained a complication, underwent revision surgery or progressed to a total hip arthroplasty (THA). In addition, we reviewed prospectively collected patient reported outcome measure (PROMs) using (SF12, HOOS, and UCLA). Survivorship outcome was described for the whole cohort and compared between the 2 surgical groups. PROMs between groups were compared using The Mann-Whitney U test and the survival between groups was assessed using the Kaplan-Meier Analysis and the Log-Rank Mantel Cox test. All analyses were performed in SPSS (IBM, v. 26.0). The cohort included 110 SDs and 320 arthroscopies. The mean age of the whole cohort was 34±10; patients in the SD group (32±9) were younger compared to the arthroscopy group (39±10) (p<0.0001). There were 16 post-operative complications (similar between groups) and 77 re-operations (more common in the SD group (n=49) due to symptomatic metal work (n=34)). The overall 10-year survival was 91±3%. Survivorship was superior in the arthroscopy group at both 5- (96% (95%CI: 93 – 100)) and 8- years 94% (95%CI: 90 – 99%) compared to the SD Group (5-yr: 90% (95%CI: 83 – 98); 8-yr: 84% (95%CI:75 – 93)) (p=0.003) (Figure 1). On average HOOS improved from 54±19 to 68±22 and WOMAC from 65±22 to 75±22. The improvement in PROMs were similar between the 2 groups. We report very good long-term joint preservation for the treatment of FAI, which is similar to those reported in hip dysplasia. In addition, we report satisfactory improvement in function following such treatment. The differences reported in joint survival likely reflect selection biases from the treating surgeon; more complex cases and those associated with more complex anatomy were more likely to have been offered a SD in order to address the pathology with greater ease and hence the inferior joint preservation identified in this group. For any figures or tables, please contact the authors directly

Arthrosis of the hip joint can be a significant source of pain and dysfunction. While hip replacement surgery has emerged as the gold standard for the treatment of end stage coxarthrosis, there are several non-arthroplasty management options that can help patients with mild and moderate hip arthritis. Therefore, the purpose of this paper is to review early prophylactic interventions that may help defer or avoid hip arthroplasty. Nonoperative management for the symptomatic hip involves minimizing joint inflammation and maximizing joint mobility through intra-articular joint injections and exercise therapy. While weight loss, activity modifications, and low impact exercises is generally recommended for patients with arthritis, the effects of these modalities on joint strength and mobility are highly variable. Intra-articular steroid injections tended to offer reliable short-term pain relief (3–4 weeks) but provided unreliable long-term efficacy. Additionally, injections of hyaluronic acid do not appear to provide improved pain relief compared to other modalities. Finally, platelet rich plasma injections do not perform better than HA injections for patients with moderate hip joint arthrosis. Primary hip joint arthrosis is rare, and therefore treatment such as peri-acetabular osteotomies, surgical dislocations, and hip arthroscopy and related procedures are aimed to minimise symptoms but potentially aim to alter the natural history of hip diseases. The state of the articular cartilage at the time of surgery is critical to the success or failure of any joint preservation procedures. Lech et al. reported in a series of dysplastic patients undergoing periacetabular osteotomies that one third of hips survived 30 years without progression of arthritis or conversion to THA. Similarly, surgical dislocation of the hip, while effective for treatment of femoroacetabular impingement, carries a high re-operation rate at 7 years follow up. Finally, as the prevalence of hip arthroscopic procedures continues to rise, it is important to recognise that failure to address the underlying structural pathologies can lead to failure and rapid joint destruction. In summary, several treatment modalities are available for the management of hip pain and dysfunction in patients with a preserved joint space. While joint preservation procedures can help improve pain and function, they rarely alter the natural history of hip disease. The status of the articular cartilage at the time of surgery is the most important predictor of treatment success or failure

Osteonecrosis (ON) is a debilitating condition that can progress to severe arthritis of the hip. While its exact pathogenesis remains poorly understood, ON is known to be associated with risk factors such as corticosteroid use, alcoholism, and autoimmune disease. Initial radiographic evaluation can reveal sclerotic and cystic changes in the femoral head, which are usually the first clues in diagnosis. Despite these indicators, plain radiographs generally are not sufficient for diagnosis, therefore requiring subsequent magnetic resonance imaging (MRI) studies. Moreover, performing an appropriate assessment of these imaging modalities can help guide the course of treatment. Treatment options are aimed at slowing or stopping the onset of femoral head collapse and include non-operative management, joint preservation procedures, and total joint arthroplasty. Patients at risk of developing ON may benefit from early diagnosis because the characteristic small or medium-sized pre-collapse lesions that are associated with this stage can often be treated with a non-operative or joint preservation approach. However, patients typically present with advanced disease progression and sometimes an unsalvageable joint, thereby necessitating more invasive operative intervention. Surgical modalities include the use of osteotomy, core decompression, vascular grafts, bone graft substitutes, resurfacing, and finally, total hip arthroplasty. Additionally, reports from the past several decades describe improved outcomes and survivorship of these surgical treatment options. Therefore, our purpose is to highlight recent evidence regarding the management of ON with emphasis on the various forms of operative intervention as well as their outcomes

Hip joint preservation remains a preferred treatment option for hips with mechanically correctable pathologies prior to the development of significant secondary arthrosis. The pathologies most amenable to joint preservation are hip dysplasia and femoroacetabular impingement. These pathologies sometimes overlap. Untreated acetabular dysplasia of modest severity, if left uncorrected, always leads to arthrosis. Acetabular dysplasia is best treated by periacetabular osteotomy, usually combined with arthrotomy for management of labral pathology and associated cam-impingement if present. Pre-operative variables associated with the best long-term outcomes include less secondary arthrosis, younger age, and concentric articular surfaces. Femoroacetabular impingement has become progressively recognised as perhaps the most common cause of secondary arthrosis. The etiology of impingement is multifactorial and includes both genetic factors and stresses experienced by the hip prior to cessation of growth. Cam impingement can be quantified by the alpha angle as measured on plain radiographs and radial MR sequences. Further, significant cam impingement is clearly associated with the development of osteoarthrosis. Treatment can be performed either by arthroscopic or open femoral head-neck osteochondroplasty. As with hip dysplasia, prognosis following treatment is correlated with the severity of preoperative secondary arthrosis but unfortunately impinging hips more commonly have some degree of arthrosis preop whereas dysplastic hips can become symptomatic with instability in the absence of arthrosis. The scientific basis for the treatment of pincer impingement is less strong. Unlike cam impingement and hip dysplasia, pincer impingement pathology in the absence of coxa profunda has not been correlated with arthrosis and so rim trimming with labral refixation is probably performed more often than is clinically indicated. Similarly, caution should be exercised when considering rim-trimming for protrusion since high central contact pressures due to an enlarged acetabular notch are not corrected by rim trimming. Overall, joint preserving surgery remains the preferred treatment for hips with mechanically correctable problems prior to the development of significant secondary arthrosis

The Hill-Sachs lesion is a bony defect of the humeral head that occurs in association with anterior instability of the glenohumeral joint. Hill-Sachs lesions are common, with an incidence approaching nearly 100% in the setting of recurrent anterior glenohumeral instability. However, the indications for surgical management are very limited, with less than 10% of anterior instability patients considered for treatment of the Hill-Sachs lesion. Of utmost importance is addressing bone loss on the anterior-inferior glenoid, which is highly successful at preventing recurrence of instability even with humeral bone loss. In the rare situation where the Hill-Sachs lesion may continue to engage the glenoid, surgical management is indicated. Surgical strategies are variable, including debridement, arthroscopic remplissage, allograft transplantation, surface replacement, and arthroplasty. Given that the population with these defects is typically comprised of young and athletic patients, biologic solutions are most likely to be associated with decades of sustainable joint preservation, function, and stability. The first priority is maximizing the treatment of anterior instability on the glenoid side. Then, small lesions of less than 10% are ignored without consequence. Lesions involving 10–20% of the humeral head are treated with arthroscopic remplissage (defect filled with repair of capsule and infraspinatus). Lesions greater than 20% that extend beyond the glenoid tract are managed with fresh osteochondral allografts to biologically restore the humeral head. Lesions great than 40% are most commonly associated with advanced arthritis and deformity of the humeral articular surface and are therefore treated with a humeral head replacement. This treatment algorithm maximises our ability to stabilise and preserve the glenohumeral joint

Aim. Different perioperative strategies have been implemented to reduce the devastating burden of infection following arthroplasty. The use of iodophor-impregnated adhesive incise drapes is one such strategy. Despite its wide adoption, there is little proof that this practice leads to a reduction of bacterial colonization. The aim of this randomized, prospective study was to evaluate the efficacy of iodophor-impregnated adhesive drapes for reducing bacterial count at the incision site. Method. A total of 96 patients undergoing open joint preservation procedure of the hip were enrolled in this prospective, randomized clinical trial of iodophor-impregnated adhesive drapes. *. One half of patients (n=48) had iodophor-impregnated adhesive drapes. *. applied to the skin prior to incision and kept on throughout the procedure, while the other half (n=48) underwent the same surgery without the use of iodophor-impregnated adhesive drapes. *. Culture swabs were taken from the surgical site at five different time points during surgery (pre-skin preparation, after skin preparation, post-incision, before subcutaneous closure, and prior to dressing application) and sent for culture and colony counts. Mixed-effects and multiple logistic regression analyses were utilized. Results. Iodophor-impregnated adhesive drapes resulted in a significant reduction of bacterial colonization of the surgical incision. At the conclusion of surgery, 12.5% (6/48) of incisions with iodophor-impregnated adhesive drapes. *. and 27.0% (13/48) without adhesive drapes were positive for bacteria. When controlling for preoperative colonization and other factors, patients without adhesive drapes were significantly more likely to have bacteria present at the incision at the time of closure (odds ratio (OR) 11.88, 95% confidence interval (CI) 1.45–80.00), and at all time-points when swab cultures were taken (OR 2.48, 95% CI 1.00–6.15). Conclusions. Based on this skin sampling study, incise draping significantly reduces the rate of bacterial colonization/contamination during hip surgery. The bacterial count at the skin was extremely high in some patients without iodophor-impregnated adhesive drapes. *. , which raises the possibility that a subsequent surgical site infection or periprosthetic joint infection could likely arise if an implant had been utilized

Introduction. Clear operative oncological margins are the main target in malignant bone tumour resections. Novel techniques like patient specific instruments (PSIs) are becoming more popular in orthopaedic oncology surgeries and arthroplasty in general with studies suggesting improved accuracy and reduced operating time using PSIs compared to conventional techniques and computer assisted surgery. Improved accuracy would allow preservation of more natural bone of patients with smaller tumour margin. Novel low-cost technology improving accuracy of surgical cuts, would facilitate highly delicate surgeries such as Joint Preserving Surgery (JPS) that improves quality of life for patients by preserving the tibial plateau and muscle attachments around the knee whilst removing bone tumours with adequate tumour margins. There are no universal guidelines on PSI designs and there are no studies showing how specific design of PSIs would affect accuracy of the surgical cuts. We hypothesised if an increased depth of the cutting slot guide for sawblades on the PSI would improve accuracy of cuts. Methods. A pilot drybone experiment was set up, testing 3 different designs of a PSI with changing cutting slot depth, simulating removal of a tumour on the proximal tibia (figure 1). A handheld 3D scanner (Artec Spider, Luxembourg) was used to scan tibia drybones and Computer Aided Design (CAD) software was used to simulate osteosarcoma position and plan intentioned cuts (figure 1). PSI were designed accordingly to allow sufficient tumour. The only change for the 3 designs is the cutting slot depth (10mm, 15mm & 20mm). 7 orthopaedic surgeons were recruited to participate and perform JPS on the drybones using each design 2 times. Each fragment was then scanned with the 3D scanner and were then matched onto the reference tibia with customized software to calculate how each cut (inferior-superior-vertical) deviated from plan in millimetres and degrees (figure 3). In order to tackle PSI placement error, a dedicated 3D-printed mould was used. Results. Comparing actual cuts to planned cuts, changing the height of the cutting slot guide on the designed PSI did not deviate accuracy enough to interfere with a tumour resection margin set to maximum 10mm. We have obtained very accurate cuts with the mean deviations(error) for the 3 different designs were: [10mm slot: 0.76±0.52mm, 2.37±1.26°], [15mm slot: 0.43±0.40mm, 1.89±1.04°] and [20mm: 0.74±0.65mm, 2.40±1.78°] respectively, with no significant difference between mean error for each design overall, but the inferior cuts deviation in mm did show to be more precise with 15mm cutting slot (p<0.05) (figure 2). Discussion. Simulating a cut to resect an osteosarcoma, none of the proposed designs introduced error that would interfere with the tumour margin set. Though 15mm showed increased precision on only one parameter, we concluded that 10mm cutting slot would be sufficient for the accuracy needed for this specific surgical intervention. Future work would include comparing PSI slot depth with position of knee implants after arthroplasty, and how optimisation of other design parameters of PSIs can continue to improve accuracy of orthopaedic surgery and allow increase of bone and joint preservation. For figures/tables, please contact authors directly.

The Hill-Sachs lesion is a bony defect of the humeral head that occurs in association with anterior instability of the glenohumeral joint. Hill-Sachs lesions are common, with an incidence approaching nearly 100% in the setting of recurrent anterior glenohumeral instability. However, the indications for surgical management are very limited, with less than 10% of anterior instability patients considered for treatment of the Hill-Sachs lesion. Of utmost importance is addressing bone loss on the anterior-inferior glenoid, which is highly successful at preventing recurrence of instability even with humeral bone loss. In the rare situation where the Hill-Sachs lesion may continue to engage the glenoid, surgical management is indicated. Surgical strategies are variable, including debridement, arthroscopic remplissage, allograft transplantation, surface replacement, and arthroplasty. Given that the population with these defects is typically comprised of young and athletic patients, biologic solutions are most likely to be associated with decades of sustainable joint preservation, function, and stability. The first priority is maximising the treatment of anterior instability on the glenoid side. Then, small lesions of less than 10% are ignored without consequence. Lesions involving 10–20% of the humeral head are treated with arthroscopic remplissage (defect filled with repair of capsule and infraspinatus). Lesions greater than 20% that extend beyond the glenoid tract are managed with fresh osteochondral allografts to biologically restore the humeral head. Lesions great than 40% are most commonly associated with advanced arthritis and deformity of the humeral articular surface and are therefore treated with a humeral head replacement. This treatment algorithm maximises our ability to stabilise and preserve the glenohumeral joint

Developmental dysplasia of the hip (DDH) is relatively a common condition that can lead to early arthritis of the hip. Although total hip arthroplasty is the surgical treatment of choice for these patients with end stage arthritis, some patients afflicted with DDH may present early. Acetabular osteotomy, in particular Bernese or periacetabular osteotomy (PAO as described by Professor Ganz and Jeff Mast back in 1980s) may be an option with patients with symptomatic DDH who have joint space available. PAO has many advantages. First, it is performed through a single incision (modified Smith Peterson approach) without breaching the abductor mechanism. The periacetabular fragment has, hence, excellent blood supply and avascular necrosis of the acetabular portion is not an issue. In addition, the osteotomy is so versatile allowing for great mobility of the fragment to obtain coverage even in the worst of circumstances. The osteotomy does not affect the posterior column and hence allows for earlier weight bearing. Most joint preservation surgeons in North America and Europe prefer PAO to other types of osteotomy. The indications for PAO are a patient with symptomatic DDH who has good joint space and a congruent joint. The congruency of the joint is usually determined by the abduction views (obtained at 30 degrees abduction and neutral rotation). Although the joint space may be measured on plain radiographs, in recent years some centers have been utilising cross sectional imaging, such as dGEMERIC for evaluation of the articular cartilage, which has been shown to be a good predictor of outcome for PAO

Purpose. Proximal femoral osteotomy is an attractive joint preservation procedure for osteonecrosis of the femoral head. The purpose of this study was to investigate the cause of failure of proximal femoral osteotomy in patients with osteonecrosis of the femoral head. Patients and Methods. Between 2008 and 2014, proximal femoral osteotomy was performed by one surgeon in 13 symptomatic hips. Ten trans-trochanteric rotational osteotomies (anterior: 7, posterior: 3) and 3 intertrochanteric curved varus osteotomy were performed. Of the patients, 9 were male and 1 was female, with a mean age at surgery of 36.9 years (range, 25–55 years). The mean postoperative follow-up period was 38 months (range, 12–72 months). Three patients (4 hips) had steroid-induced osteonecrosis, and 7 (9 hips) had alcohol-associated osteonecrosis. At 6 postoperative weeks, partial weight bearing was permitted with the assistance of 2 crutches. At more than 6 postoperative months, full weight bearing was permitted. Patients who had the potential to achieve acetabular coverage of more than one-third of the intact articular surface on preoperative hip radiography, computed tomography, and magnetic resonance imaging were considered suitable for this operation. A clinical evaluation using the Japanese Orthopaedic Association (JOA) scoring system and a radiologic evaluation were performed. Clinical failure was defined as conversion to total hip arthroplasty (THA) or progression to head collapse and osteoarthritis. The 13 hips were divided into two groups, namely the failure and success groups. Results. The mean preoperative JOA score was 59 points. The score in the success group (7 hips) improved to 89 points at the time of final follow-up. In the failure group (6 hips), 5 hips were converted to THA because of progression to secondary collapse or osteoarthritis in a mean postoperative period of 35 months (range, 24–51 months). After converting to THA, good clinical and radiographic results were achieved, except in 1 patient who had incomprehensible severe pain around the affected hip. Advanced osteoarthritis was observed in 1 hip awaiting THA. Various factors cause failure of proximal femoral osteotomy, such as difficulty in controlling the underlying disease with less than 10 mg of steroid (Fig. 1), overuse of the affected hip within 6 postoperative months without the physician's consent, vascular occlusion after total necrosis of the femoral head as a result of damage to the nutritional vessel during or after the operation, and incorrect judgement of the indication of the operation and the extent of the intact load-bearing area. Conclusion. We think that full weight bearing should be permitted postoperatively only after more than 6 months, and heavy work and sport, only after more than 1 year. Efforts should be made to improve surgeons' skill in proximal femoral osteotomy and accurate judgement of imaging data. For steroid-induced osteonecrosis of the femoral head, proximal femoral osteotomy is an acceptable procedure for relieving pain if the underlying disease can be controlled with not more than 5 mg of steroid

90% of young patients that develop DJD of the hip have an underlying structural problem, most frequently hip dysplasia. The structural problem results in decreased contact area, increased contact stresses about the anterior and lateral acetabulum and femoral head and results in labral pathology, early cartilage damage and if left untreated leads to end stage hip arthritis. Despite the optimism of alternative bearing surfaces and highly cross linked polyethylene, THA should still be discouraged in young patients. Many patients with symptomatic hip dysplasia in the absence of arthritis will benefit from joint preservation. The goal of treatment should be restoration of anatomy as close to normal as possible. The Bernese PAO is the preferred technique in many centres in North America and Europe because of its balance between minimal exposure, complications, and ability to provide optimal correction. The ideal patient for a PAO is young, has no arthritis, is not obese (BMI <30) and has poorly covered femoral head where congruency is possible. A PAO has advantages over other osteotomies and include: . 1). Performed through one incision without violation of the abductors. 2). Pelvic ring and an outlet, are not disrupted. 3). Posterior column is preserved. 4). Allow multidirectional correction. 5). Can perform capsulotomy to assess the labrum and check for impingement. The results of the osteotomy have been encouraging with up to 60% survivorship free from total hip arthroplasty at 20 years. Most studies show improvement in pain and function, improvement in radiographic coverage of the femoral head with no improvement in range of motion. Treatment should be individualised to each patient based on radiographic findings, age and cartilage status and restoration of anatomy as close to normal as possible should be the ideal treatment, most commonly in the form of a periacetabular osteotomy