Introduction. Paediatric tibial fractures, unlike femoral fractures do not have much potential for overgrowth. In simple factures of the tibial shaft treated non-operatively the major problems are shortening and malunion. In complex injuries with extensive soft tissue disruption and bone loss, the long-term aim of reconstruction is to achieve union with a fully functional limb without limb-length inequality. Methods. Four children (Age range 6-12 years) who sustained high-energy grade III open fractures of the tibia were treated with acute shortening and bone transport. Any soft tissue reconstructive and secondary grafting procedures for delayed union were recorded. The children were prospectively followed up to fracture union. Distraction ostegenesis proceeded until limb length equality was achieved and the regenerate allowed to consolidate. Results. Three children had grade 3B injuries, 2 requiring flap reconstruction. One had a grade 3A injury. Mean acute shortening was 4.4cm (Range 2-9cm). Distraction osteogenesis was used to achieve limb-length equalisation. 2 children required secondary bone graft procedures to achieve union. At 3 years from injury, all children had overgrowth of the injured leg averaging 2cm. Discussion. Despite achieving equal limb lengths at the end of distraction osteogenesis the injured tibia overgrew by a mean of 2cm at three years post injury. This would suggest that even in the presence of extensive soft tissue trauma, as seen in these high energy injuries, the increased blood flow associated with metaphyseal corticotomy stimulates epiphyseal activity resulting in overgrowth. The value of stopping adjustments just short of achieving limb length equality to allow for expected overgrowth in the injured tibia merits further investigation

Recurrent patellar instability is a common problem and there are multiple demographic and pathoanatomic risk factors that predispose patients to dislocating their patella. The most common of these is trochlear dysplasia. In cases of severe trochlear dysplasia associated with patellar instability, a sulcus deepening trochleoplasty combined with a medial patellofemoral ligament reconstruction (MPFLR) may be indicated. Unaddressed trochlear pathology has been associated with failure and poor post-operative outcomes after stabilization. The purpose of this study is to report the clinical outcome of patients having undergone a trochleoplasty and MPFLR for recurrent lateral patellofemoral instability in the setting of high-grade trochlear dysplasia at a mean of 2 years follow-up. A prospectively collected database was used to identify 46 patients (14 bilateral) who underwent a combined primary MPFLR and trochleoplasty for recurrent patellar instability with high-grade trochlear dysplasia between August 2013 and July 2021. A single surgeon performed a thin flap trochleoplasty using a lateral para-patellar approach with lateral retinaculum lengthening in all 60 cases. A tibial tubercle osteotomy (TTO) was performed concomitantly in seven knees (11.7%) and the MPFLR was performed with a gracilis tendon autograft in 22%, an allograft tendon in 27% and a quadriceps tendon autograft in 57% of cases. Patients were assessed post-operatively at three weeks and three, six, 12 and 24 months. The primary outcome was the Banff Patellar Instability Instrument 2.0 (BPII 2.0) and secondary outcomes were incidence of recurrent instability, complications and reoperations. The mean age was 22.2 years (range, 13 to 45), 76.7% of patients were female, the mean BMI was 25.03 and the prevalence of a positive Beighton score (>4/9) was 40%. The mean follow-up was 24.3 (range, 6 to 67.7) months and only one patient was lost to follow-up before one year post-operatively. The BPII 2.0 improved significantly from a mean of 27.3 pre-operatively to 61.1 at six months (p < 0 .01) and further slight improvement to a mean of 62.1 at 12 months and 65.6 at 24 months post-operatively. Only one patient (1.6%) experienced a single event of subluxation without frank dislocation at nine months. There were three reoperations (5%): one for removal of the TTO screws and prominent chondral nail, one for second-look arthroscopy for persistent J-sign and one for mechanical symptoms associated with overgrowth of a lateral condyle cartilage repair with a bioscaffold. There were no other complications. In this patient cohort, combined MPFLR and trochleoplasty for recurrent patellar instability with severe trochlear dysplasia led to significant improvement of patient reported outcome scores and no recurrence of patellar dislocation at a mean of 2 years. Furthermore, in this series the procedure demonstrated a low rate (5%) of complications and reoperations

Aims. This case series aims to describe the clinical consequences of juxta-physeal sub-acute osteomyelitis in children, specifically growth and limb deformity. Methods. All children diagnosed with osteomyelitis between 2014 and 2016 at a single University Teaching Hospital in the UK were included. Juxta-physeal sub-acute osteomyelitis was identified using magnetic resonance imaging obtained within 48-hours of presentation. These cases were followed up prospectively on a regular basis in the outpatient clinic. Any clinical evidence of limb or growth deformity was evaluated using long-leg standing radiographs. Results. During the study period, 63 paediatric osteomyelitis cases were identified and four of these (6%) had juxta-physeal sub-acute osteomyelitis. All bone infections were located either in the distal femur or proximal tibia. All cases were treated with six weeks of intravenous ceftriaxone and three children underwent surgical procedures. All four cases developed a growth deformity in the affected limb. Conclusions. A variety of growth disturbances can occur following sub-acute osteomyelitis which could be secondary to physeal stimulation and overgrowth. In this series, overgrowth occurred in the physis immediately adjacent to the Brodie's abscess. Subsequently, the presence of a medial abscess caused a valgus deformity and a lateral abscess caused a varus deformity. This phenomenon has not been well-described in the literature. The tibial and femoral physes are amongst the most active in the body, which may explain the reason for the observed overgrowth deformity in these cases. The age of the patient and the method of treatment did not appear to influence the emergence of the growth deformity. None of our patients had recurrence or development of chronic osteomyelitis within the measured time period. In view of these findings, we recommend regular follow-up including assessment for limb deformity for a minimum of 3-years following the treatment of sub-acute osteomyelitis

Introduction. Amputation or disarticulation is a reliable option for management of severe foot deformities and limb-length discrepancies, the surgical restoration of which are unpredictable or unfavourable. Of the various surgeries involving foot ablation, Syme's amputation is preferred for congenital deformities as it provides a growing, weight bearing stump with proprioception and cushioning. Materials and Methods. We reviewed data of all children who underwent Syme's amputation over the past 13 years at our institution. Surgical technique followed the same principles for Syme's but varied with surgeons. Results. Ten boys and ten girls, with an average age of 18 months and average follow up of 70 months were included in the study. The most common indication was fibular hemimelia. Wound complications were reported in three children, phantom pain in one, heel pad migration in two. None had wound dehiscence, flap necrosis, stump overgrowth, or calcaneal regrowth. None of this required surgical intervention. One child required an amputation at a higher-level secondary to a congenital malformation of nervous tissue in the affected leg. Prosthetic compatibility was 94.7 % and none used mobility aids. Six children participated in sports. Conclusions. Syme amputation is a safe and potentially advantageous procedure in children, with a low incidence of complications to offer patients with non-salvageable foot conditions. It offers good prosthetic use with minimal risk of complications and can offer patients a functional solution with only one surgical intervention throughout their childhood

Purpose:. Despite advances in limb reconstruction, there are still a number of young patients who require trans-tibial amputation. Amputation osteoplasty is a technique described by Ertl to enhance rehabilitation after trans-tibial amputation. The purpose of the present study was to evaluate the results of the original Ertl procedure in skeletally immature patients, and to assess whether use of this procedure would result in a diminished incidence of bony overgrowth. Methods:. Four consecutive patients (five amputations) treated between January 2005 and June 2008 were reviewed. Clinical evaluation consisted of completion of the prosthesis evaluation questionnaire (PEQ) and physical examination. Radiographic analysis was performed to evaluate bone-bridge healing, bone overgrowth and the medial proximal tibial angle (MPTA). Results:. The best mean PEQ result in the Question section was 91.8 (Range 74–100) for ‘Well being’ and the worst mean score was 66.6 (Range 50–78) for the sub-section ‘Residual limb health’. Examination of the residual limbs revealed no bursae were present and all knees were stable with full range of movement. All bony bridges united at an average age of 1.7 months (Range 1–2). One case required stump revision for bony overgrowth, and one case developed asymptomatic mild genu varum. Conclusions:. In this series, the original Ertl osteomyoplasty shows good functional and prosthetic use with only one bony overgrowth requiring revision surgery

Aim. Negative-pressure wound therapy (NPWT) is often propagated as treatment option for fracture-related infection (FRI). After surgical debridement and repeated NPWT dressing changes, the wounds are often closed by free flaps. Sometimes even healing by secondary intention seems an alternative. Recently, concerns have been raised on the long-term use of NPWT as it could be related to bacterial overgrowth and possible re-infection. The purpose of this study was to conduct a retrospective evaluation of the influence of long-term NPWT on tissue culture results and outcome in FRI patients. Method. Between January 1. st. , 2015 and December 31st, 2018, a total of 852 patients were treated with NPWT for different indications on the Department of Trauma Surgery. Inclusion criteria for this study were patients with a closed fracture, stabilized with osteosynthetic fixation and complicated with a confirmed FRI according to the FRI consensus definition. Patients were included when they received at least three NPWT dressing changes in the operating room. Exclusion criteria were patients younger than 18 years, or the absence of cultures results from dressing changes. Results. During the study period 23 patients met the inclusion criteria. According to the tripartite classification of Willenegger and Roth, one patient had an early, 14 a delayed and 8 patients a late onset FRI. Overall, 139 NPWT dressing applications were performed, with an average amount of six per patient. In 14 patients (61%) and 57 dressing changes (41%), at least 2 tissue cultures showed the same pathogen or at least one, in case of highly virulent organisms (e.g. S. aureus) during a single dressing exchange. Coagulase-negative staphylococci were present in 33% of the cases, followed by Enterococcus spp. (21%), S. aureus (16%), non-fermentative gram negative bacilli (14%) and Enterobacteriaceae (7%). Furthermore, 17 exchanges showed polymicrobial growth. Five patients had repeatedly significant growth of the same pathogen despite adequate antimicrobial therapy, within this group one patient was immunocompromised. Conclusions. In a large amount of patients (61%), a significant number of positive culture results could be acquired, even in the presence of adequate local and systemic antimicrobial therapy. The clinical relevance of these results remains unclear. This said, it seems important to limit the duration of NPWT as prolonged treatment could increase bacterial overgrowth and possible (re-)infection. Therefore, a rapid definitive soft tissue coverage should be encouraged. Future larger prospective clinical trials are required

The purpose of this study is to report a unique overgrowth syndrome and discuss the insights into the complex orthopaedic management. Written consent to report this case was granted. The patient's condition, wrongly diagnosed as Proteus syndrome, is characterised by a genetic mutation in PIK3CA, a critical regulator of cell growth. This lead to unregulated cellular division of fibroblasts isolated to the lower limbs. The legs weighed 117 kg, with a circumference of >110 cm. In addition to lower limb overgrowth, numerous musculoskeletal and organ pathologies have been encountered since birth requiring treatment from a wide variety of healthcare specialists and basic scientists. At 32 years, the patient developed septicaemia secondary to an infected foot ulcer. Amputation had been discussed in the elective setting, however the presence of sepsis expedited surgery. The above knee amputation took 9 hours and four assistants including a plastic surgeon. A difficult dissection revealed a deep subcutaneous fatty layer that integrated with deep muscle, massive hypertrophy of cutaneous nerves and the sciatic nerve and ossification within the distal quarter of the quadriceps muscles requiring osteotomy. The lower limb osteology was grossly aberrant. The size of the amputated limb did not permit use of a tourniquet and cell salvage reintroduced 10.5 litres of blood with a further 6 units of red cells intra-operatively. The leg stump successfully took to a split-skin graft. A unique phenomenon was witnessed post-operatively whereby the stump continued to grow due to upregulation of fibroblasts secondary to trauma. Targeted genetic therapies have been successfully developed to suppress this stump growth. This unique and unclassified overgrowth syndrome was caused by a mutation in the PIK3CA gene. Orthopaedic management of the oversized limb was complex requiring multiple surgeons and prolonged general anesthetic. A multi-disciplinary approach to this condition is required for optimizing outcomes in these patients

Introduction. Circumferential periosteal release is a rarely reported procedure for paediatric limb lengthening. The technique involves circumferential excision of a strip of periosteum from the metaphysis of the distal femur, tibia and fibula. This study aims to determine the mid to long-term effectiveness of this technique. Materials and Methods. A retrospective case series was performed of all patients undergoing circumferential periosteal release of the distal femur and/or tibia between 2006 and 2017. Data collected included demographics, surgical indication, post-operative limb-lengths and complications. Data collection was stopped if a further procedure was performed that may affect limb-length (except a further release). Leg-length discrepancies were calculated as absolute values and as percentages of the longer limb-length. Final absolute and percentage discrepancies were compared to initial discrepancies using a paired t-test. Results. Eighteen patients (11 males) were identified, who underwent 25 procedures. The mean age at first surgery was 5.83 (SD 3.49). The commonest indication was congenital limb deficiency (13 patients). In 23 procedures the periosteum was released in two limb segments (distal femur and distal tibia), whereas in two patients it was released in a single limb segment. Five patients underwent repeat periosteal release, and one patient had three periosteal releases. Mean follow-up was 63.1 months (SD 33.9). Fifteen patients had sufficient data for statistical analysis. The mean initial absolute discrepancy was 2.01cm (SD 1.13), and the mean initial percentage discrepancy was 4.09% (SD 2.76). The mean final absolute discrepancy was 1.00cm (SD 1.62), and the mean percentage final discrepancy was 1.37% (SD 2.42). The mean reduction in absolute discrepancy was 0.52 cm (95%CI −0.04–1.08; p=0.068, paired t-test), and the mean reduction in percentage discrepancy was 2.00% (95% CI 1.02–2.98, p=<0.001 paired t-test). In five patients the operated limb overgrew the shorter limb. Conclusions. Circumferential periosteal release produces a modest decrease in both absolute and percentage limb-length discrepancy, although the outcome is variable and some patients may experience overgrowth of the operated limb

Introduction. Limb length discrepancy (LLD) is one of the major reasons of dissatisfaction after total hip arthroplasty(THR) and limb equalization after THR in unilateral developmental dysplasia of the hip (DDH) is very important. study designed to measure the difference of adult femoral length between normal and dislocated hip in unilateral DDH. Method. Sixty patients with unilateral high riding DDH (crow type 3,4) who were underwent THR included. All the cases had digital lower limb scanograms. Exclusion criteria was any previous hip or femur surgery, any rheumatoid disease, history of any disease that affect the growth. All the scanograms measured by one fellowship of adult reconstruction and one radiologist specialized in musculoskeletal imaging. Each one repeated the measurements two months later blindly and inter observer and intra observer reliability checked. Each one measured femoral length in both sides from greater trochanter(GT), to the distal surface of the femoral condyles. Results. 59 female and one males included. Average age was 27.5 years (19–50 years). Inter observer reliability index were excellent (ICC 98%). Only 6 cases (10%) had exactly equal femoral length, 31(52%) cases were longer on the dislocated side and 23 (38%) cases were shorter. Average overgrowth was 6.1 mm (Range: 1–22) and average undergrowth was 10.7 (Range 1–21). 35 cases (58.3%) cases had 5 mm or more differences and 30% had 5–10 mm .17 cases (28.3%) had at least 10 mm difference that 8 cases (13%) had shorter and 9 cases (15%) had longer femur on dislocated side. Maximum difference was 22 mm over length on dislocated side. Conclusions. More than half of patients with unilateral high riding DDH have longer femur on the dislocated side and 15% of them are longer than 10 mm. we recommend to get the scanograms in all the unilateral DDH cases to avoid post-operative limb discrepancy and detecting the amount of shortening in cases that need femoral shortening

Introduction. Acetabular retroversion is an accepted cause of Pincer-type femoroacetabular impingement. There is increasing evidence that acetabular retroversion is rather a rotational abnormality of the pelvis than an overgrowth of the acetabular wall or even a dysplasia of the posterior wall. Initially, patients with a retroverted acetabulum were treated with an open rim trimming through a surgical hip dislocation (SHD) based on the early understanding of the pathomorphology. Theoretically, the reduction of the anterior wall can decrease the already small joint contact area in retroverted hips to a critical size. Based on the most recent literature, anteverting periacetabular osteotomy (PAO) seems to be the more appropriate surgical treatment. With this technique, the anterior impingement conflict can be treated efficiently without compromising the joint contact area. However, it is unknown whether this theoretical advantage in turn results in better mid term results of treatment. Objectives. We asked if anteverting PAO results in better clinical and radiographical mid term results compared to rim trimming through a surgical hip dislocation. Methods. We performed a retrospective comparative study based on 257 hips (221 patients) with symptomatic femoroacetabular impingement due to acetabular retroversion. Acetabular retroversion was defined by a cross-over sign, a posterior wall sign, and a positive ischial spine sign. We then formed two matched groups consisting of 73 hips undergoing open acetabular rim trimming and 54 hips with an anteverting periacetabular osteotomy. Patients with incomplete radiographic documentation, previous surgery, and hip dysplasia (LCE < 20°) were excluded. Some patients were excluded due to a matching process (Fig. 1). Patients were generally followed clinically and radiographically after two, five and ten years. A Kaplan-Meier survivorship analysis was performed using the following endpoints: a low clinical score, radiographic progression of osteoarthritis, and/or the conversion to total hip arthroplasty. The Log Rank Score was used to compare the two survivorship curves. Results. Patients undergoing anteverting PAO for acetabular retroversion had a significantly increased survivorship (82%, 95% confidence interval, 72–91%) at seven years in comparison to open surgical rim trimming (63%, 95%CI, 49–76%, p<0.0001). The two survivorship curves are comparable for the first four years with a substantial drop for the rim trimming group after year five (Fig. 2). Conclusion. This study proofs for the first time that the theoretical advantages of anteverting periacetabular osteotomy in hips with symptomatic acetabular retroversion results in an increased survivorship at mid term follow-up in comparison to open rim trimming. For any figures or tables, please contact authors directly (see Info & Metrics tab above).

Complex congenital foot deformities pose a challenge to the surgeon due to poor results after extensive surgery. We report the clinical outcomes of children with complex congenital foot deformities treated with UMEX® (Universal mini-external fixator System) frames. This is a prospective review of our experience in patients treated in this way, from 2004 to 2011. The indications for treatment included resistant/recurrent Congenital Talipes Equino Varus (CTEV), cavo-varus deformity secondary to Charcot-Marie-Tooth disease, arthrogryposis, fibular hemimelia and other congenital abnormalities. A total of 32 children (35 feet) have been treated, out of which 22 were male and 10 were female patients. Age at surgery ranged from 3 to 15 years (median age – 7 years). Three patients underwent bilateral procedures; the reminder (29 patients) underwent unilateral foot operations. Twenty-eight patients had undergone previous surgery including soft-tissue and/or bony corrective procedures. The frames were removed at an average of 69 days after application, and the patients spent a further 6 weeks in a walking cast. Good functional outcomes were noted in 26 patients in the first postoperative year and in 19 patients in the fifth postoperative year. Further operations were needed in 10 patients. Complications occurred in 10 patients, predominantly pin-site infections and 1 case of bony overgrowth at pin-site and 1 of proximal tibio-fibular diastasis. This is a simple fixator to use with a short learning curve. In groups of patients with complex congenital abnormalities, we achieved good functional outcome with low-complication rates

We report the clinical outcomes of children with complex congenital foot deformities treated with UMEX® mini-external fixators. This is a prospective review of our experience in patients treated in this way, from 2004. The indications for treatment were resistant/recurrent Congenital Talus Equina Varus(CTEV), cavo-varus deformity secondary to Charcot-Marie-Tooth disease, arthrogryposis, fibular hemimelia and other congenital abnormalities. In addition, one patient underwent this treatment since he was allergic to casting material. A total of 32 children (35 feet) have been treated, with a male to female ratio of 22:10 respectively. The patient-age at operation ranged between 3 and 15 years (median age −7 years). Three patients underwent bilateral procedures and 29 patients underwent unilateral foot operations. Twenty-eight patients underwent previous soft-tissue and bony corrective operations with serial casting. The frames were removed at an average of 69 days after application with a further 6 weeks in a walking cast. Seventy-nine percent of the patients had good functional outcome. Further operations were needed in 10 patients. Complications occurred in 10 patients, including pin-site infections, bony overgrowth at pin-site and proximal tibio-fibular diastasis. In conclusion, this is a simple fixator to use with a small learning curve. In groups of patients with complex congenital abnormalities, we achieved good functional outcome with low-complication rates

Aims

Limb-lengthening nails have largely replaced external fixation in limb-lengthening and reconstructive surgery. However, the adverse events and high prevalence of radiological changes recently noted with the STRYDE lengthening nail have raised concerns about the use of internal lengthening nails. The aim of this study was to compare the prevalence of radiological bone abnormalities between STRYDE, PRECICE, and FITBONE nails prior to nail removal.

Opinions about the treatment of Perthes' disease vary widely. However there is no disagreement about the need for containment during fragmentation stage to create an optimum biomechanical environment for remodelling of femoral head. Types of containment may vary. Younger children do well irrespective of the method of containment. Older children usually require surgical containment. The present study was aimed at evaluating the results of different methods of surgical containment in different age group and identifying specific factors that alter the final outcome and prognosis. 107 cases were reviewed retrospectively. 21 cases were excluded due to lack of records. 86 hips were available for clinical and radiological evaluation. 31 patients were under 7 years and required Varus osteotomy (VO). 55 patients were above 7 years. VO was performed in 30 hips and Shelf containment was done in 25. Case notes were reviewed for demographic details, surgical details and clinic letters. Radiographs were reviewed for Herring's grading, Stulberg staging, containment indices, centre edge angle, lateral pillar height, Mose index, neck shaft angle and shelf width. In all patients, there was an improvement in pre-operative symptoms and summated range of motion, especially abduction. Good functional and radiological outcome was seen in age group < 7 years. In older children, outcome was good to satisfactory with Herring grade B. Stulberg grading worsened with advancing age and Herring grade C, irrespective of the method of containment. Persistence of varus neck shaft angle and trochanteric overgrowth were significant problems with VO. Although all containment indices improved with Shelf group, Stulberg grading remained poor in most patients. The lateral pillar classification and age strongly correlate with final outcome. Herring group C had the least favourable result. Stulberg staging remained poor in older children irrespective of the method of containment

Purpose. The traditional management of pediatric aneurysmal bone cysts involves the application of intralesional resection principles that are used to treat benign aggressive tumors in general. Alternatively, some are treated by injections of sclerosing agents. The risks of these approaches include growth arrest, additional bony destruction necessitating the restoration of structural integrity, and soft tissue necrosis. We wished to evaluate the effectiveness of treating aneurysmal bone cysts in children by percutaneous curettage as a means to avoid these risks. Method. A retrospective cohort study of pediatric, histologically proven aneurysmal bone cyst patients treated either by percutaneous curettage or by open intralesional resection with two years follow up was undertaken. Those cysts judged as uncontained and requiring restoration of structural bony integrity underwent open intralesional resection and reconstruction. Contained cysts judged as not requiring immediate structural restoration were treated percutaneously. This group was uniformly treated on an outpatient basis using angled curettes under image guidance followed by intralesional evacuation using a suction trap. None in this group had insertion of any substance into the cyst cavity. Short-term casting or immobilization was undertaken in most cases. The primary outcome evaluated was radiographic resolution, persistence or recurrence at two years according to the Neer/Cole classification. Complications were noted. Results. Twenty patients with a mean age of 11 (2–15) were evaluated, with ten in each group. In the open intralesional resection group, 9/10 achieved Neer/Cole grade I resolution; one case recurred and was successfully treated percutaneously. There was one case of valgus proximal tibial overgrowth deformity requiring hemiepiphysiodesis, and three cases requiring hardware removal for irritation. In the percutaneous group, 7/10 achieved Neer/Cole grade 1 resolution, one case exhibited radiographic persistence of nonexpansile, lytic change and two cases frankly recurred, necessitating repeat procedures. No fractures, growth arrests, or infections occurred in either group. Conclusion. Not all aneurysmal bone cysts require wide exposure for intralesional resection. Percutaneous curettage is a reasonable alternative for contained aneurysmal bone cysts. Children will readily restore bone stock in the absence of bone graft or bone substitute as long as the cyst is erradicated. Percutaneous curettage should be performed selectively and on an investigational basis for the time being

Aims

The Precice intramedullary limb-lengthening system has demonstrated significant benefits over external fixation lengthening methods, leading to a paradigm shift in limb lengthening. This study compares outcomes following antegrade and retrograde femoral lengthening in both adolescent and adult patients.

Construction of a functional skeleton is accomplished through co-ordination of the developmental processes of chondrogenesis, osteogenesis, and synovial joint formation. Infants whose movement in utero is reduced or restricted and who subsequently suffer from joint dysplasia (including joint contractures) and thin hypo-mineralised bones, demonstrate that embryonic movement is crucial for appropriate skeletogenesis. This has been confirmed in mouse, chick, and zebrafish animal models, where reduced or eliminated movement consistently yields similar malformations and which provide the possibility of experimentation to uncover the precise disturbances and the mechanisms by which movement impacts molecular regulation. Molecular genetic studies have shown the important roles played by cell communication signalling pathways, namely Wnt, Hedgehog, and transforming growth factor-beta/bone morphogenetic protein. These pathways regulate cell behaviours such as proliferation and differentiation to control maturation of the skeletal elements, and are affected when movement is altered. Cell contacts to the extra-cellular matrix as well as the cytoskeleton offer a means of mechanotransduction which could integrate mechanical cues with genetic regulation. Indeed, expression of cytoskeletal genes has been shown to be affected by immobilisation. In addition to furthering our understanding of a fundamental aspect of cell control and differentiation during development, research in this area is applicable to the engineering of stable skeletal tissues from stem cells, which relies on an understanding of developmental mechanisms including genetic and physical criteria. A deeper understanding of how movement affects skeletogenesis therefore has broader implications for regenerative therapeutics for injury or disease, as well as for optimisation of physical therapy regimes for individuals affected by skeletal abnormalities.

Cite this article: Bone Joint Res 2015;4:105–116