Introduction. Classical fixation using a circular frame involves two rings per segment and in many units this remains the norm whether using ilizarov or hexapod type frames. We present the results of two ring circular frame at King's College Hospital. Materials & Methods. A prospective database has been maintained of all frames applied since 2007. Radiographs from frames applied prior to July 2022 were examined. Clinic letters were then used to identify complications. Included: two ring hexapod for fracture, malunion, nonunion, arthrodesis or deformity correction in the lower limb. Excluded: patients under 16 years old, diabetic feet, Charcot joints, soft tissue contractures, arthrodiastasis, correction of the mid/forefoot, plate fixation augmentation, fixation off a third ring. Results. 518 two ring hexapods were identified. Mean age was 46 (16–89). 55% were for fracture, 18% for malunion, 11% for nonunion. Mean frame time was 7 months (2–29 months). All clinic letters from 384 patients showed 203 patients (52%) had at least one pin site infection, 27 nonunions (7%), 16 frame revisions (4%), 25 bone grafting procedures (7%), 5 cases of septic arthritis (1%), 3 periprosthetic fractures (0.8%),), 12 malunions (3%), 4 Amputations (1%). Conclusions. These results demonstrate the efficacy of a two ring hexapod for patients requiring reconstruction of the lower limb

Introduction. Sheffield Children's Hospital specialises in limb lengthening for children. Soft tissue contracture and loss of range of motion at the knee and ankle are common complications. This review aims to look at therapeutic techniques used by the therapy team to manage these issues. Materials & Methods. A retrospective case review of therapy notes was performed of femoral and tibial lengthening's over the last 3 years. Included were children having long bone lengthening with an iIntramedullary nail, circular frame or mono-lateral rail. Patients excluded were any external fixators crossing the knee/ankle joints. Results. 20 tibial and 25 femoral lengthening's met the inclusion criteria. Pathologies included, complex fractures, limb deficiency, post septic necrosis and other congenital conditions leading to growth disturbance. All patients had issues with loss of motion at some point during the lengthening process. The knee and foot/ankle were equally affected. Numerous risk factors were identified across the cohort. Treatment provided included splinting, serial casting, bolt on shoes, exercise therapy, electrical muscle stimulation and passive stretching. Conclusions. Loss of motion in lower limb joints was common. Patients at higher risk were those with abnormal anatomy, larger target lengthening's, poor compliance or lack of access to local services. Therapy played a significant role in managing joint motion during treatment. However, limitations were noted. No one treatment option gave preferential outcomes, selection of treatment needed to be patient specific. Future research should look at guidelines to aid timely input and avoid secondary complications

Introduction. External fixators are common surgical orthopaedic treatments for the management of complex fractures and in particular, the use of circular frame fixation within patients requiring limb reconstruction. It is well known that common complications relating to muscle length and patient function without rehabilitation can occur. Despite this there remains a lack of high-quality clinical trials in this area investigating the role of physiotherapy or rehabilitation in the management of these patients. We aim to complete a systematic review of rehabilitation techniques for patients undergoing external fixator treatment for Limb Reconstruction of the lower limb. Materials & Methods. A comprehensive search of AMED, CINAHL, MEDLINE and COCHRANE databases was conducted to identify relevant articles for inclusion, using a search strategy developed in collaboration with a research librarian. Inclusion criteria consisted of adults aged 18 years and over who have experienced leg trauma (open fracture, soft tissue damage), elective leg deformity corrective surgery, bone infection or fracture non-union who have been treated with the use of an external fixator for fixation. Specific exclusion criteria were patients below the age of 18 years old, patients with cancer, treatment of the injury with internal nail, patients who underwent amputation, the use of external fixators for soft tissue contracture management, editorials, comment papers, review papers, conference proceedings and non-English papers. Titles, abstracts, and full texts were screened for suitability by pairs of reviewers according to the inclusion and exclusion criteria using Rayyan QCRI online software. Any conflicts were resolved through discussion with three independent specialist senior reviewers. Following full text screening, references lists of included articles were manually searched to ensure that all relevant studies were identified. Due to lack of evidence, forward searching was also completed for studies included in the review. Data quality was assessed using the mixed methods appraisal tool and the CERT assessment tool was utilised to look at completeness of reporting of exercise interventions. Results. A total number of 832 articles were initially retrieved from our search once duplicate articles removed. After title and abstract screening, 45 articles remained for full text screening. Of these, 11 articles met our inclusion criteria and included for data extraction. Conclusions. We expect high variability of results due to our inclusion criteria and therefore plan to conduct a narrative synthesis to summarise the findings whilst measing against the mixed methods appraisal tool and CERT assessment scores to assess the data quality. We anticipate lower assessment scores within the fewer articles found and therefore poorer-quality data. We currently are in the process of finalising this data extraction. This will be completed ready for submission and potential presentation at the BLRS conference in March 2023

While the definition of “stiffness” after shoulder arthroplasty remains controversial, loss of range of motion in the post-arthroplasty setting can be a disabling functional complication. Fortunately, the incidence of post-operative loss of both active and passive range of motion is relatively less common following shoulder replacement procedures. Certain pre-operative diagnoses (proximal humeral fracture, capsulorraphy arthropathy, revision arthroplasty) are associated with post-operative soft tissue contractures. Certain medical comorbidities (diabetes, inflammatory arthropathy) are associated with periarticular capsular adhesions at the intracellular level. Management of the “stiff” shoulder arthroplasty must account for several confounding variables: . Appropriateness of diagnosis leading to arthroplasty. Humeral and glenoid implants (size, version, hemi vs TSA vs RSA). Bone variables (fracture, bone loss/erosion). Soft tissue variables (rotator cuff, glenohumeral capsule). Patient comorbidities. Techniques for management include soft tissue contracture release (manipulation, arthroscopic, open) and component revision

Arthritis of the hip is a relatively common problem in patients with neuromuscular disorders due to muscle imbalance around the hip from weakness, paralysis, contractures and spasticity. Neuromuscular disorders such as cerebral palsy, Parkinson's disease, poliomyelitis, previous cerebrovascular accident (CVA) and Charcot arthropathy have been considered by many to be contraindications to total hip arthroplasty (THA). The presence of certain anatomic abnormalities (excessive femoral anteversion, acetabular dysplasia, leg length discrepancy (LLD) and coax valga) and significant soft tissue contractures, muscle imbalance, and muscular weakness make THA a challenging surgical procedure in this patient population, and can predispose to dislocation and poor functional outcome following surgery. THA can, however, result in substantial pain relief and functional improvement, and can be safely performed, provided certain technical considerations are addressed. The patient's motor strength and functional status (ambulatory vs. “sitter”) should be carefully assessed preoperatively, since both of these factors may affect the choice of surgical approach and component position. Significant soft tissue contractures should be released at the time of surgery. Although these can be frequently performed “open”, percutaneous adductor tenotomy is occasionally necessary for patients with significant adduction contractures. Patients requiring significant soft tissue releases may benefit from 6 weeks of bracing to allow soft tissues to heal in appropriately and minimise risk of dislocation during this period of time. Use of modular femoral components that allow for correction of excessive femoral anteversion, should be considered in patients with coexistent dysplasia and neuromuscular disease (i.e., CP or polio). Large femoral head components should also be considered in patients with increased risk factors for dislocation. Despite their obvious theoretical advantages, the use of large head metal on metal THAs should be used with extreme caution in view of growing concerns about these devices. Although constrained acetabular liners are associated with an increased risk of mechanical failure, their use should be strongly considered in patients with significant motor weakness or major soft tissue deficiencies. Meticulous soft tissue closure of the capsule of the hip is recommended, especially when performing THA through a posterior approach. Patients with neuromuscular disorders associated with spasticity and involuntary movements need to be optimally treated medically prior to and indefinitely after THA. There are limited reports of outcomes following THA in patients with neuromuscular disorders, however, some generalizations based on underlying diagnosis can be made. Patients with cerebral palsy and polio frequently have acetabular dysplasia, excessive femoral anteversion and LLD, and although durability does not seem to be a major concern, dislocation and instability is relatively common and needs to be addressed. Durability and instability do not appear to be major concerns in patients with Parkinson's disease, however, these patients have frequent medical complications perioperatively and have deterioration in function over time due to the progressive nature of their underlying disorder. Patients with previous CVA also appear to have acceptable durability and dislocation risk, but are at high risk of developing heterotopic ossification postoperatively. Patients with Charcot arthropathy or myelodysplasia are at high risk of instability and appear to have limited functional improvement following THA. As a result, the consensus of opinion is that THA is contraindicated in these patients

Arthritis of the hip is a relatively common problem in patients with neuromuscular disorders due to muscle imbalance around the hip from weakness, paralysis, contractures and spasticity. Neuromuscular disorders such as cerebral palsy, Parkinson's disease, poliomyelitis, previous cerebrovascular accident (CVA) and Charcot arthropathy have been considered by many to be relative contraindications to total hip arthroplasty (THA). The presence of certain anatomic abnormalities (excessive femoral anteversion, acetabular dysplasia, leg length discrepancy (LLD) and coax valga) and significant soft tissue contractures, muscle imbalance, and muscular weakness make THA a challenging surgical procedure in this patient population, and can predispose to dislocation and poor functional outcome following surgery. THA can, however, result in substantial pain relief and functional improvement in patients with significant hip arthritis and neuromuscular disorders, and can be safely performed, provided certain technical considerations are addressed. The patient's motor strength and functional status (ambulatory vs. “sitter”) should be carefully assessed pre-operatively, since both of these factors may affect the choice of surgical approach and component position. Significant soft tissue contractures should be released at the time of surgery. Although these can be frequently performed “open”, percutaneous adductor tenotomy is occasionally necessary for patients with significant adduction contractures. Patients requiring significant soft tissue releases may benefit from 6 weeks of bracing to allow soft tissues to heal appropriately and minimise risk of dislocation during this period of time. Use of modular femoral components that allow for correction of excessive femoral anteversion, should be considered in patients with coexistent dysplasia and neuromuscular disease (i.e. CP or polio). Large femoral head components should also be considered in patients with increased risk factors for dislocation. Despite their obvious theoretical advantages, the use of large head metal on metal THAs should be used with extreme caution in view of growing concerns about these devices. Although constrained acetabular liners are associated with an increased risk of mechanical failure, their use should be strongly considered in patients with significant motor weakness or major soft tissue deficiencies. Meticulous soft tissue closure of the capsule of the hip is recommended, especially when performing THA through a posterior approach. Patients with neuromuscular disorders associated with spasticity and involuntary movements need to be optimally treated medically prior to and indefinitely after THA. There are limited reports of outcomes following THA in patients with neuromuscular disorders, however some generalisations based on underlying diagnosis can be made. Patients with cerebral palsy and polio frequently have acetabular dysplasia, excessive femoral anteversion and LLD, and although durability does not seem to be a major concern, dislocation and instability is relatively common and needs to be addressed. Durability and instability do not appear to be major concerns in patients with Parkinson's disease, however, these patients have frequent medical complications perioperatively and have deterioration in function over time due to the progressive nature of their underlying disorder. Patients with previous CVA also appear to have acceptable durability and dislocation risk, but are at high risk of developing heterotopic ossification postoperatively. Patients with Charcot arthropathy or myelodysplasia are at high risk of instability and appear to have limited functional improvement following THA. As a result, the consensus of opinion is that THA is contraindicated in patients with Charcot arthropathy and myelodysplasia

Arthritis of the hip is a relatively common problem in patients with neuromuscular disorders due to muscle imbalance around the hip from weakness, paralysis, contractures and spasticity. Neuromuscular disorders such as cerebral palsy, Parkinson's disease, poliomyelitis, previous cerebrovascular accident (CVA) and Charcot arthropathy have been considered by many to be relative contraindications to total hip arthroplasty (THA). The presence of certain anatomic abnormalities (excessive femoral anteversion, acetabular dysplasia, leg length discrepancy (LLD) and coax valga) and significant soft tissue contractures, muscle imbalance, and muscular weakness make THA a challenging surgical procedure in this patient population, and can predispose to dislocation and poor functional outcome following surgery. THA can, however, result in substantial pain relief and functional improvement in patients with significant hip arthritis and neuromuscular disorders, and can be safely performed, provided certain technical considerations are addressed. The patient's motor strength and functional status (ambulatory vs. “sitter”) should be carefully assessed pre-operatively, since both of these factors may affect the choice of surgical approach and component position. Significant soft tissue contractures should be released at the time of surgery. Although these can be frequently performed “open,” percutaneous adductor tenotomy is occasionally necessary for patients with significant adduction contractures. Patients requiring significant soft tissue releases may benefit from 6 weeks of bracing to allow soft tissues to heal in appropriately and minimize risk of dislocation during this period of time. Use of modular femoral components that allow for correction of excessive femoral anteversion, should be considered in patients with coexistent dysplasia and neuromuscular disease (i.e. CP or polio). Large femoral head components should also be considered in patients with increased risk factors for dislocation. Despite their obvious theoretical advantages, the use of large head metal on metal THAs should be used with extreme caution in view of growing concerns about these devices. Although constrained acetabular liners are associated with an increased risk of mechanical failure, their use should be strongly considered in patients with significant motor weakness or major soft tissue deficiencies. Meticulous soft tissue closure of the capsule of the hip is recommended, especially when performing THA through a posterior approach. Patients with neuromuscular disorders associated with spasticity and involuntary movements need to be optimally treated medically prior to and indefinitely after THA. There are limited reports of outcomes following THA in patients with neuromuscular disorders, however some generalisations based on underlying diagnosis can be made. Patients with cerebral palsy and polio frequently have acetabular dysplasia, excessive femoral anteversion and LLD, and although durability does not seem to be a major concern, dislocation and instability is relatively common and needs to be addressed. Durability and instability do not appear to be major concerns in patients with Parkinsons disease, however, these patients have frequent medical complications perioperatively and have deterioration in function over time due to the progressive nature of their underlying disorder. Patients with previous CVA also appear to have acceptable durability and dislocation risk, but are at high risk of developing heterotopic ossification post-operatively. Patients with Charcot arthropathy or myelodysplasia are at high risk of instability and appear to have limited functional improvement following THA. As a result, the consensus of opinion is that THA is contraindicated in patients with Charcot arthropathy and myelodysplasia

Longevity of total hip arthroplasty (THA) is dependent upon avoiding both short- and long-term problems. One of the most common short-term / early complications of THA is instability while longer term issues of wear remain a concern. Both of these concerns appear to be related to implant position: either static or functional. While achieving “ideal” implant position in primary THA for osteoarthritis is only successful in 50% of cases (Callanan et al.), it is even more difficult in complex primary disorders such as dysplasia and post-traumatic arthritis. Many theories exist as to why implant position and short-term complications appear to be higher in this “complex primary” cohort but certainly the ability to achieve desired implant position appears to be more challenging. The loss of usual anatomic landmarks, the presence of soft tissue contractures, and the recognition of both pelvic and femoral deformities play a role. Enabling technologies have emerged to help in achieving improved implant position. These technologies include both navigation (both imageless and image guided) as well as the newly adopted technology of robotic assistance. Robot-assisted THA is based upon a CT scan protocol. Three-dimensional pre-operative planning on both the femoral and acetabular side can be performed. Precision guided bone preparation and exacting implant delivery is achievable using robotic technology. Examples of use of this technology in complex primary THA will be demonstrated including planning, preparation and implantation

Introduction. The anatomic abnormalities are observed in developmental dysplasia of the hip (DDH) and it is challenging to perform the total hip arthroplasty (THA) for some DDH patients. If acetabular cup was placed at the original acetabular position in patients with high hip dislocation, it may be difficult to perform reduction of hip prosthesis because of soft tissue contracture. The procedures resolving this problem were to use femoral shortening osteotomy, or to place the acetabular cup at a higher cup position than the original hip center. Femoral shortening osteotomy has some concerns about its complicated procedure, time consuming, and risk of non-union. Conversely, implantation of the acetabular cup at the higher cup position may eliminate these shortcomings and this procedure is considered to be preferred if possible. However, the criteria of cases without femoral shortening osteotomy are not clear. In this study, we retrospectively analysed the clinical outcomes of patients performed THAs for high hip dislocation, and clarified the adaptation of THA with or without femoral shortening osteotomy. Methods. We included a total of 65 hip joints from 57 patients who underwent primary THA using Modulus stem for high hip dislocation from November 2007 to December 2015 at our institution. The mean follow up period was 5.2 years (2 – 10 years). The mean age at surgery was 65.4 years (Table 1). Thirty seven hips were classified as Crowe III, and twenty eight hips as Crowe IV based on Crowe classification. We classified patients into two groups based on the use of femoral osteotomy. Then, we compared the surgical time, blood loss, Japanese Orthopaedic Association (JOA) Score as clinical outcomes, preoperative position of the greater trochanter, the cup position, and complications between two groups. The position of the greater trochanter was measured the height of the tip of greater trochanter from the inter teardrop line. The cup center position was assessed by measuring the distance between the cup center and ipsilateral tear drop. Receiver operating characteristic (ROC) curves were plotted for deciding the cut-off value for the height of the greater trochanter. The cut-off value presented the maximum sensitivity and specificity was determined. Results and Discussion. Fifty three THAs were operated without femoral shortening osteotomy, and twelve THAs were performed with femoral shortening osteotomy. The surgical time was significantly longer in the osteotomy group than the non-osteotomy group. The mean height of the tip of the greater trochanter were 53.2±11.4mm in the non-osteotomy group and 92.2±19.7 mm in the osteotomy group (Table 2). The cut-off value of the height of greater trochanter evaluated from the ROC curve analysis was 69.5mm (Fig.1). There were no significant differences in clinical score between two groups. More ratio of revisions and fractures were observed in the osteotomy group with significant differences. Conclusion. There were significant differences in postoperative complications in osteotomy group compare to non-osteotomy group. In cases with a greater trochanter tip height of 69.5 mm or less, it may be considered to avoid femoral shortening osteotomy

Deformity correction is a fundamental goal in total knee arthroplasty. Severe valgus deformities often present the surgeon with a complex challenge. These deformities are associated with abnormal bone anatomy, ligament laxity and soft tissue contractures. Distorted bone anatomy is due to bone loss on the lateral femoral condyle, especially posteriorly. To a lesser extent bone loss occurs from the lateral tibia plateau. The AP axis (Whiteside's Line) or epicondylar axis must be used as a rotational landmark in the severely valgus knee. Gap balancing techniques can be helpful in the severely valgus knee, but good extension balance must be obtained before setting femoral rotation with this technique. Coronal alignment is generally corrected to neutral or 2- to 3-degree overcorrection to mild mechanical varus to unload the attenuated medial ligaments. The goal of soft tissue releases is to obtain rectangular flexion and extension gaps. Soft tissue releases involve the IT band, posterolateral corner/arcuate complex, posterior capsule, LCL, and popliteus tendon. Assessment of which structures is made and then releases are performed. In general, pie crust release of the IT band is sufficient for mild deformity. More severe deformities require release of the posterolateral corner / arcuate and posterior capsule. I prefer a pie crust technique, while Ranawat has described the use of electrocautery to perform these posterior/ posterolateral releases. In most cases the LCL is not released, however, this can be released from the lateral epicondyle, if necessary. Good ligament balance can be obtained in most cases, however, some cases with severe medial ligament attenuation require additional ligament constraint such as a constrained condylar implant

Deformity correction is a fundamental goal in total knee arthroplasty. Severe valgus deformities often present the surgeon with a complex challenge. These deformities are associated with abnormal bone anatomy, ligament laxity and soft tissue contractures. Distorted bone anatomy is due to bone loss on the lateral femoral condyle, especially posteriorly. To a lesser extent bone loss occurs from the lateral tibia plateau. The AP Axis (Whiteside's Line) or Epicondylar axis must be used as a rotational landmark in the severely valgus knee. Gap balancing techniques can be helpful in the severely valgus knee, but good extension balance must be obtained before setting femoral rotation with this technique. Coronal alignment is generally corrected to neutral or 2- to 3-degree overcorrection to mild mechanical varus to unload the attenuated medial ligaments. The goal of soft tissue releases is to obtain rectangular flexion and extension gaps. Soft tissue releases involve the IT band, Posterolateral Corner/Arcuate Complex, Posterior Capsule, LCL, and Popliteus Tendon. Assessment of which structures is made and then releases are performed. In general Pie Crust release of the ITB is sufficient for mild deformity. More severe deformities require release of the Posterolateral Corner/Arcuate Complex and Posterior Capsule. I prefer a pie crust technique, while Ranawat has described the use of electrocautery to perform these posterior/ posterolateral releases. In most cases the LCL is not released, however, this can be released from the lateral epicondyle, if necessary. Good ligament balance can be obtained in most cases, however, some cases with severe medial ligament attenuation require additional ligament constraint such as a constrained condylar implant

Deformity correction is a fundamental goal in Total Knee Arthroplasty. Severe valgus deformities often present the surgeon with a complex challenge. These deformities are associated with abnormal bone anatomy, ligament laxity and soft tissue contractures. Distorted bone anatomy is due to bone loss on the lateral femoral condyle, especially posteriorly. To a lesser extent bone loss occurs from the lateral tibia plateau. The AP Axis (Whiteside's Line) or Epicondylar axis must be used as a rotational landmark in the severely valgus knee. Gap balancing techniques can be helpful in the severely valgus knee, but good extension balance must be obtained before setting femoral rotation with this technique. Coronal alignment is generally corrected to neutral or 2 to 3 degree overcorrection to mild mechanical varus to unload the attenuated medial ligaments. The goal of soft tissue releases is to obtain rectangular flexion and extension gaps. Soft tissue releases involve the IT band, Posterolateral corner/Accurate Complex, Posterior Capsule, LCL, and Popliteus Tendon. Assessment of which structures is made and then releases are performed. In general Pie Crust release of the ITB is sufficient for mild deformity. More severe deformities require release of the Posterolateral corner/Accurate Complex and Posterior Capsule. I prefer a pie crust technique, while Ranawat has described the use of electrocautery to perform these posterior/ posterolateral releases. In most cases the LCL is not released, however, this can be released from the lateral epicondyle if necessary. Good ligament balance can be obtained in most cases, however, some cases with severe medial ligament attenuation require additional ligament constraint such as a constrained condylar implant

Melorheostosis is a very rare mesenchymal dysplasia of bone, characterized by sclerosing hyper-pigmentation appearances on the bone, may involve the adjacent soft tissues and lead to joint pain, limitation of joint motion and stiffness as a result of abnormal ossifications and soft tissue contractures, due to periarticular fibrosis. It is well known to tend to affect only one limb, but multifocal involvement, such as multiple limbs, spine and rib, has been extremely rarely reported. A variety of treatment options have been tried so far, none being specific surgical treatments. Here we present a case of a 43-year-old man who sustained melorheostosis with multifocal involvement including the axial skeleton and a whole entire lower limb. He had painful swelling of his left lower limb and mainly complained of difficulty walking due to severe hip pain and knee stiffness, which persisted for 20 years and was aggravated during the last 5 years. Total hip arthropasty [Fig. 1] was done first, and then total knee arthroplasty [Fig. 2, 3] was performed. During operation, there were difficulties in bone cutting and implant insertion due to mixed pattern of hard sclerotic portion and osteoporotic portion despite complete synovectomy and sufficient soft tissue release. He was eventually free of pain during walking and able to walk without a crutch and joint motion of hip and knee was substantially improved after surgery. We found that hip pain and contracture due to osteoarthritis and knee contracture secondary to multifocal melorheostosis could be successfully treated by total hip and knee arthroplasty. To the best of our knowledge, this is the first reporting the total joint arthroplasty performed in the patients with multifocal melorheostosis

We present the results of a new non-invasive lengthening nail enabling accurate control of the lengthening process and joint rehabilitation. Introduction. The use of intramedullary lengthening nails have gained popularity as they reduce common complications associated with external fixators, including infection, joint stiffness, bone regenerate deformity, late fracture and patient implant acceptance. Current nails however are associated with complications including implant breakage, mechanical failure, runaway nail and requiring MUA to restart or obtain segment lengthening. The Precice nail incorporates magnet technology with a hand held device allowing non-invasive lengthening. The nail is also reversible allowing shortening if required. Physiotherapy can continue throughout treatment to maintain joint range of motion without concern of uncontrolled nail runaway. The lengthening is axial reducing shear/torsional forces on the regenerate. Method. The lengthening of 4 femora was undertaken in 3 patients, mean age 34 yrs for post-traumatic shortening and short stature. A standard technique included an Ilizarov corticotomy followed by a 6 day latent period. Patients were mobilised partial weight bearing and knee range of motion maintained. The femora were lengthened one third of a millimetre three times per day. Radiographic and clinical review was performed every 2 weeks. Results. The desired femoral length was obtained in all patients, mean 5.6 cms (4.5–6.5). There were no complications of infection, poor bone regenerate or premature consolidation. One patient undergoing bilateral femoral lengthening underwent surgical release of a tight Tensor Fascia Lata following completion of lengthening due to hip flexion contracture. One patient required slowing of the lengthening rate due to knee flexion contracture. Physiotherapy corrected the deformity and the normal lengthening rate could be resumed. Conclusion. The Precice nail is a new device that offers accurate control of the lengthening process and rehabilitation. This should reduce complications of poor regenerate formation and soft tissue contractures

Background. Total hip arthroplasty for Crowe type IV developmental dysplasia of the hip is a technically demanding procedure. Restoration of the anatomical hip center frequently requires limb lengthening in excess of 4 cm and increases the risk of neurologic traction injury. However, it can be difficult to predict potential leg length change, especially in total hip arthroplasty for Crowe type IV developmental hip dysplasia. The purpose of the present study was to better define features that might aid in the preoperative prediction of leg length change in THAs with subtrochanteric femoral shortening osteotomy for Crowe type IV developmental dysplasia of the hip. Patients and Methods. Primary total hip arthroplasties with subtrochanteric femoral shortening osteotomy were performed in 70 hips for the treatment of Crowe type IV developmental hip dysplasia. The patients were subdivided into two groups with or without iliofemoral osteoarthritis. Leg length change after surgery was measured radiographically by subtracting the amount of resection of the femur from the amount of distraction of the greater trochanter. Preoperative passive hip motion was retrospectively reviewed from medical records and defined as either higher or lower motion groups. Results. The preoperative flexion of patients without iliofemoral osteoarthritis was significantly higher than for patients with iliofemoral osteoarthritis. All hips without iliofemoral OA had higher motion. The preoperative flexion in the higher motion group both with and without iliofemoral OA was significantly greater than in the lower group with iliofemoral OA (Figure 1). Leg length change in patients without iliofemoral osteoarthritis was significantly greater than with iliofemoral osteoarthritis (Figure 2), and the higher hip motion group had greater leg length change in THA than the lower motion group. No clinical evidence of postoperative neurologic injury was observed in patients with iliofemoral OA. Postoperative transient calf numbness in the distribution of the sciatic nerve was observed in 2 of 25 hips without iliofemoral OA (8.0%), however, no sensory and motor nerve deficit was observed. Discussion. The authors hypothesized that preoperative hip motion could affect soft tissue contractures, and our findings suggest that the soft tissues surrounding the hip joint with iliofemoral OA should be more contracted than the hip without OA. We also found leg length change in the higher motion group was greater than in the lower motion group. Previous studies reported limb lengthening in excess of 4 cm could increase the risk of nerve palsy. Transient calf numbness in the distribution of the sciatic nerve was observed in 2 hips without iliofemoral OA and their leg length change was not greater than 4 cm. Our findings suggest that hips without iliofemoral OA should be paid attention to protect the nerves from excessive elongation. The current study identifies several features that might help predict leg length change during the preoperative planning of total hip arthroplasty for Crowe type IV developmental hip dysplasia

Aims/Hypothesis. The aims of this study were: 1) to quantitatively analyse the amount of knee extension that is achieved with +2mm incremental increases in the amount of distal femoral bone that is resected during TKA in the setting of a flexion contracture, 2) to quantify the amount of coronal plane laxity that occurs with each 2mm increase in the amount of distal femur resected. In the setting of a soft tissue flexion contracture, we hypothesized that although resecting more distal femur will reliably improve maximal knee extension, it will ultimately lead to increased varus and/or valgus laxity throughout mid-flexion. Methods. Seven fresh-frozen cadaver legs from hip-to-toe underwent TKA with a posterior stabilized implant using a measured resection technique with computer navigation system equipped with a robotic cutting-guide, in this IRB approved, controlled laboratory study. After the initial tibial and femoral resections were performed, the posterior joint capsule was sutured (imbricated) through the joint space under direct visualization until a 10° flexion contracture was obtained with the trial components in place, as confirmed by computer navigation. Two distal femoral recuts of +2mm each where then subsequently made and after the remaining femoral cuts were made, the trail implants were reinserted. The navigation system was used to measure overall coronal plane laxity by measuring the mechanical alignment angle at maximum extension, 30°, 60° and 90° of flexion, when applying a standardized varus/valgus load of 9.8 [Nm] across the knee using a 4kg spring-load located at 25cm distal to the knee joint line.(Figure 1) Coronal plane laxity was defined as the absolute difference (in °) between the mean mechanical alignment angle obtained from applying a standardized varus and valgus stress at 0°, 30, 60° and 90°. Each measurement was performed three separate times and averaged. The maximal extension angle achieved following each 2mm distal recut was also recorded. Two-tailed student's t-tests were performed to analyze whether there was difference in the mean laxity at each angle and if there was a significant improvement in maximal extension with each recut. P-values < 0.05 were considered significant. Results. For a 10° flexion contracture, performing the first distal recut of +2mm increased overall coronal-plane instability by approximately 3° at 30° and 60° of flexion (p < 0.05).(Figure 2) Performing the second recut of +4mm further increased mid-flexion instability by another 2° (p < 0.01).(Figure 2) Maximum extension increased from 10° of flexion to 6.4° (±2.5° SD, p < 0.005) and to 1.4° (±1.8° SD, p < 0.001) of flexion with each 2mm recut of the distal femur. Conclusions. Using a reliable, accurate, and reproducible method of measuring coronal plane laxity and maximal knee extension, we have shown that in the setting of a flexion contracture or tight extension space during TKA, recutting the distal femur by 2 mm will effectively increase the amount of maximal extension by 4°; however, as a secondary effect, recutting the distal femur by 2 mm will also lead to 2.5° of increased coronal plane laxity in midflexion