Purpose. Factors contributing to chronic postoperative pain (CPOP) are poorly defined in young people and developmental considerations are poorly understood. With over 5 million children undergoing surgery yearly and 25% of adults referred to chronic pain clinics identifying surgery as the antecedent, there is a need to elucidate factors that contribute to CPOP in young people. The present study includes patients undergoing hip preservation surgery at a children's hospital. Methods. The HOOS and the SF-12 Health Survey were administered to 614 patients prior to surgery with 422 patients completing follow-up data (6-months, 1-year, and 2-years post-surgery). Examining baseline characteristics for those who completed follow-up versus those who did not, the only significant difference was that patients with more than one surgery were less likely to complete follow-up measures. Pain, quality of life, and functioning across time were examined using SAS PROC TRAJ procedure, a mixture model that estimates a regression model for each discrete group within the population. Longitudinal pain trajectories were empirically grouped. Baseline preoperative characteristics of age, gender, preoperative pain, quality of life, functioning, and mental health that could potentially distinguish trajectory groups were examined. Results. A three trajectory model (low pain, pain improvement, and high pain) emerged indicating three different treatment responders. Pain trajectory groups did not differ significantly on gender, presurgical age, BMI, prior hip surgery, surgical type, joint congruence, or Tönnis grade. The pain trajectory groups differed significantly from each other on presurgical pain, pain chronicity, quality of life, and functioning. Those in the high pain group and pain improvement group endorsed having presurgical depression at significantly higher rates and lower presurgical quality of life compared to those in the low pain group (p<.01). Similarly, those in the high pain group reported significantly worse functioning prior to surgery compared to the pain improvement group (p<.0001) and those in the low pain group (p<.0001). Conclusions. Chronic pain is a common problem and surgery can be a trigger. There may be a subset of hip preservation surgery patients who are predisposed to chronic pain independent of hip health. The results demonstrate the need for preoperative screening prior to hip preservation surgery. A prospective, interventional study to identify patients at risk for a poor pain trajectory is underway. Significance. This is the largest study to date to examine longitudinal pain, quality of life, and functioning trajectories for adolescent and young adults undergoing hip preservation surgery. Chronic pain is a serious public health concern, with the United States spending $19 billion annually on pain-related disability. Identifying predictors of poor long-term outcomes in adolescents and young adult samples with postoperative pain may prevent the development of chronic pain into adulthood as well as inform presurgical preparation and postsurgical care

Management of the young adult hip pathologies is a special entity in orthopaedic surgical practice that needs special emphasis and consideration. A wide range of pathological and traumatic conditions occur in the young adult hip that lead to functional disability and the development of premature osteoarthritis. Proper surgical interference when the hip is still in the pre-arthritic stage restores function to the young hip and protects it from early degenerative changes, and hence the anticipated need for future joint replacement surgery is prevented. Accurate estimation of the biomechanical error combined with careful understanding of the hip joint biology is the cornerstone of success of any hip preservation surgery ever performed to save the young adult hip. Safe surgical hip dislocation approach was adopted as one of the tools in the hands of the hip preservation surgeon to treat a broad spectrum of intra-articular hip pathologies like Perthes disease and severe forms of slipped capital femoral epiphysis (SCFE). Osteo-chondroplasty at the head-neck junction with relative femoral neck lengthening for Perthes disease, and Subcapital re-orientation of severe SCFE based on its retinacular vascular pedicle are often performed via the surgical hip dislocation approach. The approach is also useful with certain types of acetabular fractures that enables fixation of dual-column fractures via single approach with intra-articular visualization for the accuracy of reduction and hardware placement. The 4 cm mini-open direct anterior approach is ideal for the surgical treatment of cases with cam and/or pincer types of femoro-acetabular impingement. Peri-articular osteotomies performed either on the acetabular or the femoral sides of the hip joint are extremely useful in the correction of the biomechanical error that led to an existing hip pathology. Periacetabular osteotomies are commonly performed to treat dysplasia of the young hip. Proximal femoral osteotomies are commonly performed to treat a wide range of hip pathologies including non-unions of femoral neck fractures in the young adult. Correction of the biomechanical error at the proper timing ensures normalization of the hip joint loading conditions and range of motion that leads to reversal of the pathologic process and prevention of osteoarthritis. A hip joint replacement would have an unknown but certainly a finite life, whereas a young hip that has healed after hip preservation surgery would definitely last for a lifetime

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

There is currently no standardised complication grading classification routinely used for paediatric orthopaedic surgical procedures. The Clavien-Dindo classification used in general surgery was modified and validated in 2011 by Sink et al. and has been used regularly to classify complications following hip preservation surgery. The aim of this study was to adapt and validate Sink et al.'s modification of the Clavien-Dindo classification system for grading complications following surgical interventions of the upper and lower extremities and spine in paediatric orthopaedic patients. Sink et al.'s modification of the Clavien-Dindo classification system was further modified for paediatric orthopaedic procedures. The modified grading scheme was based on the treatment required to treat the complication and the long term morbidity of the complication. Grade I complications do not require deviation from standard treatment. Grade II complications deviate from the normal post-operative course and require outpatient treatment. Grade III complications require investigations, re-admission or re-operation. Grade IV complications are limb or life threatening or have a potential for permanent disability (IVa: with no long term disability and IVb: with long-term disability). Grade V complications result in death. Forty-five complication scenarios were developed. Seven paediatric orthopaedic surgeons were trained to use the modified system and they each graded the scenarios on two occasions. The scenarios were presented in a different random order each time they were graded. Fleiss' and Cohen's k statistics were performed to test for inter-rater and intra-rater reliabilities, respectively. The overall Fleiss' k value for inter-rater reliability was 0.772 (95% CI, 0.744–0.799). The weighted k was 0.765 (95% CI, 0.703–0.826) for Grade I, 0.692 (95% CI, 0.630–0.753) for Grade II, 0.733 (95% CI, 0.671–0.795) for Grade III, 0.657(95% CI, 0.595–0.719) for Grade IVa, 0.769 (95% CI, 0.707–0.83) for Grade IVb and 1.000 for Grade V (p value <0.001). The Cohen's k value for intra-rater reliability was 0.918 (95% CI, 0.887–0.947). These tests show that the adapted classification system has high inter- and intra-rater reliabilities for grading complications following paediatric orthopaedic surgery. Given the high intra- and inter-rater reliability and simplicity of this system, adoption of this grading scheme as a standard of reporting complications in paediatric orthopaedic surgery could be considered. Since the evaluation of surgical outcomes should include the ability to reliably grade surgical complications, this reproducible, reliable system to assess paediatric surgical complications will be a valuable tool for improving surgical practices and patient outcomes