Metal-on-Metal devices generate significantly lower volumetric wear than conventional total hip replacements. However, clinically some patients may suffer some form of laxity in their joints leading to subluxation of the joint, which in turn may cause edge loading of an implant thereby increasing the chances of failure due to higher than expected wear. In this study, the effect of subluxation on MoM implant wear was investigated on a hip joint simulator. Materials & Methods. Two groups of 44 mm MoM devices were tested, n=3 in each group. The devices were subjected to 1 and 2 mm of subluxation. The flexion/extension was 30° and 15° respectively, internal/external rotation was ±10°, and cup inclination was 35°. The force was Paul type stance phase loading with a maximum load of 3 kN, with ISO swing phase load of 0.3 kN, run at 1 Hz. The test was carried out on a ProSim deep flexion & subluxation hip wear simulator (SimSol, UK). Rather than separating the head and the cup (microseparation), or reducing the swing phase load, this simulator is equipped with a novel mechanism to achieve translation of the head, while subjecting the devices to subluxation. During the swing phase, a controlled lateral force necessary for the translation of the head is applied by a cam mechanism, head retraction will then take place on heel strike. The lubricant used was new born calf serum with 0.2 wt. % sodium azide concentration diluted with de-ionised water to achieve average protein concentration of 20 g/l. Lubricant was changed every 250k cycles. Gravimetric wear measurements have been taken at 0.25 & 0.5 Mc stages. Results. Tests conducted with 1mm (Group 1) and 2mm (Group 2) subluxation significantly increased volumetric wear compared to standard hip simulator tests [1]. At 0.5 million cycles, group 1 and 2 produced an average volume loss of 4.38±0.98 mm. 3. (95% CL) and 7.07±1.64 mm. 3. (95% CL) respectively. Discussion/conclusion. Well positioned and well-fixed hip implants perform well in vitro and in vivo; however optimal performance a device can be affected by a number of factors from design, technical factors, patient factors, surgical technique to position of the device in vivo. The study presents test results of a hip joint simulator with a subluxation mechanism to simulate clinically relevant subluxation during the swing phase of a gait cycle under the ISO swing phase load of 0.3kN, with differing levels of luxation. Increasing the level of subluxation in turn increased volumetric wear due to greater head contact at the superior rim of the cup. Further tests will be conducted with high cup inclination angles (>45°) and subluxation to determine the effect upon wear. Tests which can simulate the (ideal and adverse) conditions clinically can help to improve the design and understanding of implant behaviour in vivo

Permanent patellar subluxation is treated with surgeries such as proximal realignment and distal realignment, however, it is difficult to cure this condition by using any methods. We performed mobile-bearing total knee arthroplasty (TKA) in a case of severe knee osteoarthritis complicated with permanent patellar subluxation since childhood, and obtained good results without performing any additional procedures. The patient was an 82-year-old woman with severe pain in the left knee. During the initial examination, the range of motion of the left knee joint was -10°of extension to 140°of flexion, and the Japanese Orthopaedic Association (JOA) score for knee osteoarthritis was 40 points (maximum score: 100). Preoperative radiographs showed a varus deformity in the left lower extremity with a femorotibial angle (FTA) of 188°, the axial view showed luxation of the patella. We performed TKA using a mobile-bearing implant. Intraoperative findings revealed that the central articular surface of the distal femur had disappeared, and that the patellar articular surface was concave and dome-shaped. The lateral patellofemoral ligament was released; this procedure was identical to that performed in conventional TKA. Postoperative radiographs showed good alignment, with an FTA of 173°. In the axial view, the patella was located in a reduced position at any angle of knee joint flexion. The postoperative range of motion of the left knee joint was 0°of extension to 130°of flexion. The patient was able to walk without the support of a T-shaped cane. There are many surgical treatments for permanent patellar subluxation. The appropriate treatment is selected according to the type and seriousness of the dislocation and the age of the patient. From the findings of the present case, we believe that in a case of knee osteoarthritis complicated with permanent patellar subluxation, surgery performed using a mobile-bearing implant would eliminate the necessity of performing additional proximal realignment and distal realignment

Background. Current literature of definition, classification and outcomes of fractures of talar body remains controversial. Our primary purpose is to present an unusual combination of fractures of talar body with pantalar involvement / dislocation / extension as a basis for modification of Müller AO / OTA Classification. Methods. We include four consecutive patients, who sustained talar body fractures with pantalar subluxation/dislocation /extension. These unusual injury patterns lead us to reconsider Müller AO / OTA Classification in the light of another widely used talar fracture classification, Hawkins Classification of fractures of neck of talus and subsequent modification by Canale and Kelly. Results. Müller AO / OTA Classification comprises CI – Ankle joint involvement, C2 – Subtalar joint involvement, C3 – Ankle and subtalar joint involvement. We propose Modification of Müller AO / OTA. Classification. C1 – Absolutely undisplaced fracture; C2 – Ankle and Subtalar joint involvement: subluxation; C3 – Ankle and subtalar joint involvement: subluxation with comminution; C4 – Ankle, subtalar and talonavicular joint involvement. Conclusions. Our modification redefines Müller AO / OTA Classification, extends and fills the void in the classification by inclusion of C4, draws attention to stability of talonavicular joint and reflects increasing severity of injury in fractures of talar body

This study of retrieved 28 mm Metasul™ (cemented) revealed for the first time adverse wear effects created by impingement-subluxation in MOM. The 10 cases selected (with femoral stems) had annual follow-up 3–11 years. (1) Unequivocal evidence here shows that all heads routinely subluxed from the Metasul liners. Femoral stems revealed well-demarcated notches (DN) on necks and trunnions (Fig. 1a: n = 6), shallow cosmetic blemishes (Fig. 1b CB: n = 4), and abrasion by cement (Fig. 1b: PMMA). As demonstrated by EOS radiographs, impingement locations varied with implant positioning, pelvic mobility and patient functionality – both anterior and posterior notching (Fig. 1). The first impingement notch occurred with head located (Fig. 2a), whereas the head had subluxed from the cup at 2. nd. notch (Fig. 2b). The model demonstrated that patients gained 20° motion by such head-subluxation manoeuvres. It was surprising that there was no collateral damage evident on the liners. Even with severe notching of Ti6Al4V and CoCr stems, the cup rims generally appeared well-polished. Femoral heads revealed macro-stripe damage on articular surfaces (Fig. 3), as did cups. Basal and polar macro-stripes on heads were always located at hip impingement positions. The equatorial stripes were formed at main-wear zone boundaries. Thus equatorial stripes were likely created by some form of rim-impact damage (micro-separation) or by local ingress of 3. rd. -body wear particles under the cup rim. Micro-grooving was evident within these macro-size stripes and frequently featured large raised lips (Fig. 3), interpreted as signs of adverse 3. rd. -body wear mechanisms, and rarely described.(2) It would appear that large metal particulates were released during MOM impingement-subluxation manoeuvres and circulated the hip joint to producing severe 3. rd. -body abrasion. Gradual decomposition of such large debris to nano-sized particulates under joint loading would then produce the often-referenced ‘self polishing’ effect of CoCr. EDS studies revealed metal smears on the CoCr surfaces containing the elements of titanium alloy (Ti, Al, V). This was further evidence of impingement-subluxation manoeuvres.(1, 3). In-vivo cup wear patterns also appeared much larger than those produced in MOM simulators. Such differences likely reflected head-subluxation in vivo, whereby heads unconstrained by the subluxation maneuver were free to orbit up and even cross cup rims, i.e. “edge wear”. This appears to be the first study detailing the adverse wear mechanisms in MOM bearings. There are two limitations to our retrieval study, a) these wear results may not be representative for all MOM designs, and b) it is unknown whether such results have relevance to MOM cases continuing successfully

Atlanto-axial subluxation (AAS) presents with marked frequency among patients with instability in rheumatoid arthritis (RA) patients. This study investigated the morphology of the atlanto-occipital joint (AOJ) in AAS patients due to RA using computed tomography, and examined the relationship between its morphology and other radiographic results. Twenty-six consecutive patients with AAS due to RA treated by surgery were reviewed. In all patients, the AOJ was morphologically evaluated using sagittal reconstruction view on computed tomography before surgery. Moreover, the ADI value was investigated at the neutral position, and atlanto-axial angle (AAA) at the neutral and maximal flexion position in preoperative lateral cradiographs. The morphology of the AOJ was classified into three types as follows: a normal type which showed a maintenance of the joint space, a narrow type which showed a disappearance of the joint space and a fused type which showed the fusion of the AOJ. The pre-operative CT image of the AOJ demonstrated a normal type bilaterally in six cases (Group A). In 15 cases (Group B), CT image demonstrated narrowing on at least one side of the AOJ. In five cases (Group C), CT images demonstrated fusion on at least one side of the AOJ. The average ADI value at the flexion position was 10.7 mm in Group A, 11.7 mm in Group B, and 12.6 mm in Group C. There was no significant difference among those groups. The average ADI value at the neutral position before surgery was 2.8 mm in Group A, 5.9 mm in Group B, and 10.4 mm in Group C. There was no significant difference between Group A and B, and Group B and C; however, there was a significant difference between Group A and C (p < 0.004). The average AAA value was 25.3 degrees in Group A, 19.3 degrees in Group B and 3.4 degrees in Group C. There was no significant difference between Group A and B; however, there was a significant difference between Group A and C (p < 0.002), and Group B and C (p < 0.007). This study showed that fusion or ankylosis of the AOJ induced an enlargement of the ADI and anterior inclination of the atlas in the neutral position—despite the fact that normal findings of AOJ showed a slight displacement of the atlas to axis in RA patients showing AAS involvement

In order to manage painful subluxation/dislocation secondary to cerebral palsy, 12 hips in 11 patients received combined femoral and Chiari pelvic osteotomies with additional soft tissues releases at an average age of 14.1 (9.1-17.8) years. Pain relief, improvement in the arc of movement, sitting posture and ease of perineal care was recorded in all, and these features have been maintained at an average follow-up of 13.1 (8-17.5) years. The improvement of general mobility was marginal, but those who were community walkers benefited the most. Pre-operative radiological measurements have been modified post-operatively to use lateral margin of the neo-acetabulum produced by the pelvic osteotomy. The radiological migration index improved from a mean of 80.6% to 13.7% [p<0.0001]. The mean changes in CE angle and Sharp's angle were 72° (range 56°- 87°) [p<0.0001] and 12.3° (range 9°- 15.6°) [p< 0.0001] respectively. Radiological evidence of progressive arthritic change was seen in only one hip, in which only a partial reduction had been achieved, and there was early joint space narrowing in another. Heterotopic ossification was observed in one patient with athetoid quadriplegia who remained pain free. In seven hips the lateral Kawamura approach, elevating the greater trochanter, provided exposure for both osteotomies and allowed the construction of a dome-shaped iliac osteotomy, while protecting the sciatic nerve. This combined procedure provides a stable hip with sustained pain relief for the adolescent and young adult presenting with pain

Damage to metal-on-metal bearings (MOM) has been varyingly described as “edge wear,” third-body abrasive wear and “rim-damage” (1–4). However, no distinction has been made between any of these proposed wear mechanisms. The goal of this study was to discover what features might differentiate between surface damage created by either 2-body or 3-body wear mechanisms in MOM bearings. The hypotheses were that surface damage created by impingement of the cup rim (2-body wear) would be i) linear on the micro-scale, ii) reveal transverse striations (in direction of the sliding rim), iii) have either no raised lip or have a single lip along one side of the track, and iv) have an asymmetrical surface profile across the track width.

Five cases with 28 mm MOM, five of 34–38 mm MOM, and five of 50–56 mm diameter were studied (N = 15). The main wear zone (MWZ) was measured in each MOM head and the number of 2-body wear tracks recorded in the non-wear (NWZ) and main wear zone (MWZ). Bearing damage was examined using a white-light interferometer (Zygo Newview 600; 5x lens) and a scanning electron microscope (Zeiss MA15). The depths and slopes were assessed across the width of the damage tracks.

Thirteen of the 15 MOM bearings showed wear tracks that exhibited all four of the hypothesized 2-body wear characteristics. These wear tracks will be referred to as “micro-segments”. While micro-segments visually appeared linear, microscopically they revealed a semi-lunar edge coupled with transverse striations leading to a linear edge. This indicated that during impingement episodes, the cup rim ploughed material from the CoCr surface at the semi-lunar edge (Fig. 1), thereby creating the abruptly raised lip on the linear edge of the track. This “snow plough effect” and its distinct edge effect can account for the asymmetrical surface profile. A different type of 2-body wear was identified and referred to as “furrows”. Furrows also visually appeared linear visually, but microscopically revealed longitudinal striations and a symmetrical surface profile (Fig. 2). Furrows had lips raised on both sides of the track, but not circumscribing the terminal ends of the track. Instead, the ends of the furrows are tapered smooth transitions to the articular surface.

Thus, 2-body tracks were found to be distinguishable from 3-body tracks (micro-grooves) and were classified as either micro-segments or furrows. Micro-segements supported hypotheses 1–3 and provided a clearer definition for hypothesis-4, while furrows only supported hypothesis 1. The divergence in features between micro-segments and furrows allude to different interactions between the bearing and cup rim that led to each type of track. While these data represent a small set of cases (n = 15) this evidence shows for the first time what was previously only suspected (2), that the CoCr rim can routinely create 2-body wear damage mechanisms in MOM femoral heads.

Previously, we conducted a multi-center, double-blinded randomized controlled trial comparing arthroscopic Bankart repair with and without remplissage. The end point for the randomized controlled trial was two years post-operative, providing support for the benefits of remplissage in the short term in reducing recurrent instability. The aim of this study was to compare the medium term (3 to 9 years) outcomes of patients previously randomized to have undergone isolated Bankart repair (NO REMP) or Bankart repair with remplissage (REMP) for the management of recurrent anterior glenohumeral instability. The rate of recurrent instability and instances of re-operation were examined. The original study was a double-blinded, randomized clinical trial with two 1:1 parallel groups with recruitment undertaken between 2011 and 2017. For this medium-term study, participants were reached for a telephone follow-up in 2020 and asked a series of standardized questions regarding ensuing instances of subluxation, dislocation or reoperation that had occurred on their shoulder for which they were randomized. Descriptive statistics were generated for all variables. “Failure” was defined as occurrence of a dislocation. “Recurrent instability” was defined as the participant reporting a dislocation or two or more occurences of subluxation greater than one year post-operative. All analyses were undertaken based on intention-to-treat whereby their data was analyzed based on the group to which they were originally allocated. One-hundred and eight participants were randomized of which 50 in the NO REMP group and 52 in the REMP group were included in the analyses in the original study. The mean number of months from surgery to final follow-up was 49.3 for the NO REMP group and 53.8 for the REMP group. The rates of re-dislocation or failure were 8% (4/52) in the REMP group at an average of 23.8 months post-operative versus 22% (11/50) in the NO REMP at an average of 16.5 months post-operative. The rates of recurrent instability were 10% (5/52) in the REMP group at an average of 24 months post-operative versus 30% (15/50) in the NO REMP group at an average of 19.5 months post-operative. Survival curves were significantly different favouring REMP in both scenarios. Arthroscopic Bankart repair combined with remplissage is an effective procedure in the treatment of patients with an engaging Hill-Sachs lesion and minimal glenoid bone loss (<15%). Patients can expect favourable rates of recurrent instability when compared with isolated Bankart repair at medium term follw-up

Introduction. Intramedullary lengthening devices have been in use in older children with closed /open growth plates with good success. This study aims to present the early experience of the FITBONE nail since withdrawal of the PRECICE nail. Materials & Methods. Retrospective analysis of both antegrade and retrograde techniques were utilized. Only patients where union was achieved and full weight bearing commenced were included. The complication rate, length gained, distraction index, weight bearing index (WBI) as well as mechanical axes were analysed. Results. 14 (7 males, 7 females) of a total of 16 (7 males, 7 females) patients with a mean age of 16.9 years with varied diagnosis of LLD were analysed. The mean length gained was 38 mm with an average distraction index of 0,74 mm/day. WBI in these patients on average was 59,6 days/cm lengthened. 6 complications were observed, including two nonunions (successfully treated) and a knee subluxation. Mechanical axis deviation improved from 13,3 mm to 6 mm on average. Overall there has been a nonsignificant tendency for WBI to decrease (Spearman's rank correlation coefficient −0.47, p=0.08) with increasing number of cases done, while no correlation between length gained and WBI (−0.01, p=0.96, respectively) was observed. Some nuances will be discussed. Conclusions. Limb lengthening with the FITBONE nail is relatively safe and efficient, however no significant change was seen in the outcome with previous motorized nails

Abstract. The aim is to describe the safety and efficacy of TAL in out-patient clinics when managing diabetic forefoot ulcers. Patients and Methods. Consecutive patients, who underwent TAL and had minimum 12m follow-up were analysed. Forceful dorsiflexion of ankle was avoided and patients were encouraged to walk in Total contact cast for 6-weeks and further 4-weeks in walking boot. Results. 142 feet in 126 patients underwent this procedure and 86 feet had minimum follow-up of 12m. None had wound related problems. Complete transection of the tendon was noted in 3 patients and one-patient developed callosity under the heel. Ulcers healed in 82 feet (96%) within 10 weeks however in 12 feet (10%), the ulcer recurred or failed to heal. MRI showed plantar flexed metatarsals with joint subluxation. The ulcer in this subgroup healed following proximal dorsal closing wedge osteotomy. Conclusion. Tightness of gastroc-soleus-Achilles complex and subluxed MTP joint from soft tissue changes due to motor neuropathy result in increased forefoot plantar pressures. A 2-stage approach as described result in long-term healing of forefoot ulcers, and in 96% of patients, the ulcer healed following TAL alone. TAL is a safe and effective out-patient procedure with improved patient satisfaction outcomes

Introduction. Genu valgum is a common presentation in paediatric patients with congenital limb deformities. The aim of this study is to assess the outcome of guided growth surgery in paediatric patients referred via our physiotherapy pathway with isolated genu valgum and associated patellar instability. Materials & Methods. Patients were identified from our prospective patellar instability database. Inclusion criteria was acquired or congenital genu valgum associated with patellar instability in skeletally immature patients. The mechanical lateral-distal femoral angle was assessed on long leg alignment radiographs (mLDFA <85 degrees). Surgical treatment was the placement of a guided growth plate (PediPlate, OrthoPediatrics, USA) on the medial distal femoral physis (hemi-epiphysiodesis). KOOS-child scores were collected pre-operatively and post-operatively (minimum at 6 months). Results. Eleven patients (seven female) with mean age of 12(range 5–15) were identified. Five patients had congenital talipes equinovarus(CTEV), one fibular hemimelia, one di-George syndrome, one septic growth arrest and three had idiopathic genu valgum. Pre- and post-operative KOOS-child scores showed overall improvement: 58(range 36–68) to 88(65–99) and knee symptoms subscores: 64(43–71) to 96(68–100) p<0.01, t-test. Mean follow-up was 10 months (range 3–23). No subsequent dislocations/subluxations occurred during follow-up. Conclusions. Guided growth surgery is an effective way of treating symptomatic patellar instability in skeletally immature patients with genu valgum in the absence of other structural pathology. It was most common in our cohort in patients with unilateral CTEV. We would recommend to screen syndromic and congenital limb deformity patients for patellar instability symptoms in the presence of genu valgum

The Lisfranc fracture dislocation of the tarsometatarsal joint (TMTJ) is a complex injury with a reported incidence of 9.2 to 14/100,000 person-years. Lisfranc fixation involves dorsal bridge plating, transarticular screws, combination or primary arthrodesis. We aimed to identify predictors of poor patient reported outcome measures at long term follow up after operative intervention. 127 patients underwent Lisfranc fixation at our Level One Trauma Centre between November 2007 and July 2013. At mean follow-up of 10.7 years (8.0-13.9), 85 patients (66.92%) were successfully contacted. Epidemiological data including age, gender and mechanism of injury and fracture characteristics such as number of columns injured, direction of subluxation/dislocation and classification based on those proposed by Hardcastle and Lau were recorded. Descriptive analysis was performed to compare our primary outcomes (AOFAS and FFI scores). Univariate analysis and multivariate regression analysis was done adjusted for age and sex to compare the entirety of our data set. P<0.05 was considered significant. The primary outcomes were the American Orthopaedic Foot and Ankle Society (AOFAS) Midfoot Score and the Foot Function Index (FFI). The number of columns involved in the injury best predicts functional outcomes (FFI, P <0.05, AOFAS, P<0.05) with more columns involved resulting in poorer outcomes. Functional outcomes were not significantly associated with any of the fixation groups (FFI, P = 0.21, AOFAS, P = 0.14). Injury type by Myerson classification systems (FFI, P = 0.17, AOFAS, P = 0.58) or open versus closed status (FFI, P = 0.29, AOFAS, P = 0.20) was also not significantly associated with any fixation group. We concluded that 10 years post-surgery, patients generally had a good functional outcome with minimal complications. Prognosis of functional outcomes is based on number of columns involved and injured. Sagittal plane disruption, mechanism and fracture type does not seem to make a difference in outcomes

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

Introduction. Hip dysplasia is the most common congenital deformity of the musculoskeletal system. This is a pathology that brings the hip joint from subluxation to dislocation. Frequency of hip dysplasia − 16 children per 1000 newborns. Materials and Methods. Diagnostic methods of research are X-ray inspection which is necessarily carried out at internal rotation (rotation) of an extremity as lateral rotation of a hip on the radiograph always increases an angle of a valgus deviation of a neck. Surgical treatment is performed in the subclavian area of the femur. An external fixation device is applied and a corrective corticotomy is performed, and valgus deformity and anteversion are eliminated. The duration of treatment is 2.5–3 months. Results. Frequency of hip dysplasia − 16 children per 1000 newborns. We perform about 30 operations a year, including 60% girls and 40% boys. In addition, valgus deformity can be traced -. - in cerebral palsy. - after polio. - at progressing muscular dystrophies. - tumor in the area of the epiphyseal cartilage. At insufficient stability in a hip joint at insufficiently expressed roof of an acetabulum of rotational deformation of a neck of a hip, for prevention of a coxarthrosis and normalization of a ratio of articular ends operation detorsion-varying subvertebral corticotomy of a femur is shown. Conclusions. The operation is minimally invasive, with accesses of 5–6 mm, anatomical and topographical features are taken into account, which will eliminate damage to tissues, nerve trunks and the circulatory system

Introduction. Acquired chronic radial head (RH) dislocations present a significant surgical challenge. Co-existing deformity, length discrepancy and RH dysplasia, in multiply operated patients often preclude acute correction. This study reports the clinical and radiological outcomes in children, treated with circular frames for gradual RH reduction. Materials and Methods. Patient cohort from a prospective database was reviewed to identity all circular frames for RH dislocations between 2000–2021. Patient demographics, clinical range and radiographic parameters were recorded. Results. From a cohort of 127 UL frames, 30 chronic RH dislocations (14 anterior, 16 posterior) were identified. Mean age at surgery was 10yrs (5–17). Six pathologies were reported (14 post-traumatic, 11 HME, 2 Nail-Patella, 1 Olliers, OI, Rickets). 70% had a congruent RH reduction at final follow-up. Three cases re-dislocated and 6 had some mild persistent incongruency. Average follow up duration was 4.1yrs (9mnths-11.5yrs). Mean radiographic correction achieved in coronal plane 9. o. , sagittal plane 7. o. and carrying angle 12. o. Mean ulna length gained was 7mm and final ulnar variance was 7mm negative (congenital). All cases achieved bony union with 2 requiring bone grafting. Mean frame duration was 166 days. Mean final range of motion was 64. o. supination, 54 . o. pronation, 2. o. to 138. o. flexion. 5 complications and 7 further operations were reported. Conclusions. The majority of children having frame correction achieve complete correction or minor subluxation, which is well tolerated clinically. Frame assisted reduction is an effective tool for selective complex cases irrespective of the pathology driving the RH dislocation

The primary objective of this study was to establish a safety profile for an all-arthroscopic anatomic glenoid reconstruction via iliac crest autograft augmentation for the treatment of shoulder instability with glenoid bone loss. Short-term clinical and radiological outcomes were also evaluated. This study involved a retrospective analysis of prospectively collected data for 14 patients (male 8, female 6) who were treated for shoulder instability with bone loss using autologous iliac crest bone graft between 2014 and 2018. Of 14 patients, 11 were available for follow-up. The safety profile was established by examining intra-operative and post-operative complications such as neurovascular injuries, infections, major bleeding, and subluxations. Assessment of pre-operative and post-operative Western Ontario Shoulder Instability (WOSI) index, radiographs, and CT scans comprised the evaluation of clinical and radiological outcomes. A good safety profile was observed. There was no occurrence of intraoperative complications, neurovascular injuries, adverse events, or major bleeding. One patient did develop an infection in the neurovascular injuries, adverse events, or major bleeding. One patient did develop an infection in the treated shoulder post-surgery. There were no subluxations or positive apprehension tests on clinical examination post-operatively. Short-term clinical outcomes were seen to be favorable WOSI scores at the most recent follow-up were significantly higher than pre-operative scores, with a mean increase of 39.6 ± 10.60 (p = 0.00055). The average follow-up for CT scan was 4.66 (SD± 2.33) months, where all patients showed bone graft union. Arthroscopic treatment of shoulder instability with bone loss via autologous iliac crest bone graft is shown to be a safe operative procedure that results in favorable short-term clinical and radiological outcomes. Further investigations must be done to evaluate the longevity of these positive health outcomes

INTRODUCTION. It has been reported that the rate of complications around the patella after Total Knee Arthroplasty(TKA) is 1–12%, and the patella dislocation is the most common one. PURPOSE. We will report a case that had the patella dislocation after TKA caused by malrotation of the components. CASE. 67 years old, Female. The chief complaint was an instability of the right patella. She had undergone TKA due to osteoarthritis at another hospital. After 2 months, she felt a subluxation of the patella. And after 4 months, she had a reoperation of medial reefing and revision of the patella at the same hospital, and the doctor allowed her to flex her right knee within 70 degrees. However, after 3 months, she started experiencing pain with a feeling of dislocation and got it corrected and immobilized with a knee brace. 2 weeks later, she visited our hospital for the first time. STATUS. 148cm, 65kg. She could gait with an extension knee brace. Tenderness was seen around the right patella. She could bend her right knee from 0 degrees to 60 degrees. Extension lag and instability of varus and valgus were not existent. An X-ray showed the FTA was 172 degrees on the right side. The right knee had a TKA(Stryker Scorpion Energy®/fixed surface), and the measurements of component after TKA were almost good. However, the patella had lateral subluxation. A CT image showed the femoral component inserted in internal rotation of 8 degrees from CEA and tibia component inserted in internal rotation of 23 degrees from the left Akagi line. We diagnosed right knee dislocation because of rotation failure of the components. COURSE OF TREATMENT. We replaced implants which were produced by the same company. We replaced the tibial component externally referring to the Akagi's line. On the femur side, we augumented the femur component at the posterolateral and replaced it referring to the CEA. We made a lateral release and used a CCK surface. We did not replace the patella because the surviving patella bone was thin and patella tracking was satisfactory.2 weeks after the operation, she could bend her knee from 0 degrees to 120 degrees and walk with a cane. An X-ray showed the patella was reduced and a CT scan showed the appropriate rotation angle. DISCUSSION. Regarding the treatment of patella dislocation after TKA, when there is malrotation of components, revision is recommended. The definition and the degree of malrotation are still controversial. It was reported that when total internal rotation angle was more than 7 degrees, Revision is recommended. This patient obtained the stability of patella due to the proper rotation angle of components

Performance of metal-on-metal (MOM) bearings was of great interest until recently. Major concerns emerged over high incidence of MOM-wear failures and initially there appeared greater risks with MOM total hip arthroplasty (THA) designs compared to resurfacing arthroplasty (RSA). Impingement of the metal neck against the THA cup was likely the differentiating risk. There is a major difference between RSA and THA in (i) size of femoral necks and (ii) risk of THA metal necks impinging on metal cups. For example, a 46mm THA with 12.5mm neck, a 3.68 head:neck (H/N) ratio, provides a suitably large range-of-motion (ROM). In contrast, an RSA patient with retained 31mm size of natural neck would only have H/N = 1.48, indicating even less ROM than a Charnley THA. However, the enigma is that RSA patients have as good or better ROM in majority of clinical studies. We studied this apparent RSA vs THA dilemma by examining MOM retrievals for signs of adverse impingement. We previously described CoCr stripe wear in failed THA bearings, notably alignment of polar and basal wear stripes coincident with the rim profiles of the cups (Clarke 2013). Our governing hypothesis was that RSA patients had to routinely sublux their hips to get ROM comparable to THA. Our THA impingement studies showed polar stripes within 15o of the polar axis in large heads. For the various RSA diameters, we calculated that wear stripes angled 40o from the femoral axis could indicate impingement with no subluxation, whereas smaller angles would indicate routine subluxation of RSA femoral-shell from cup. We compared explanted RSA (N=15) and THA (N=15) bearings representing three vendors (42–54mm diameters). Wear maps and head-stripes were ink-marked for visualization, photography, and analysis. Wear areas were calculated using spherical equations and wear-stripe angles measured by computer graphics. The results showed that RSA femoral shells had wear areas circular in shape with areas varying 1,085- 3,121mm2. These averaged 14% larger than in matched THA heads but statistically significant difference was not proven. Polar stripes were readily identifiable on femoral components, 75% for RSA cases and 100% for THA. These contained identical linear scratches and all were sited within 30o of neck axis, confirming our hypothesis that RSA patients had to sublux their hips to achieve same motion as THA. Examination of cup wear areas revealed all showed ‘edge-loading’, but RSA cups had a significantly greater degree. Retrieval studies are limited by uncontrolled case sources, varied brands, and small numbers. In this study, we were able to match RSA and THA cases by vendor and diameter. The RSA retrievals revealed polar stripes identical to THA by site, topography and inclination to femoral-neck axis. This confirmed our starting hypothesis and explained the large clinical ROM available in RSA patients. The larger wear areas on RSA femoral shells, although not statistically significant, and the larger ‘edge loading’ sites in RSA cups appeared as further support for routine subluxation of femoral-shells during hip impingement

Severe glenoid bone loss in patients with osteoarthritis with intact rotator cuff is associated with posterior glenoid bone loss and posterior humeral subluxation. Management of severe glenoid bone loss during shoulder arthroplasty is controversial and technically challenging and options range from humeral hemiarthroplasty, anatomic shoulder replacement with glenoid bone grafting or augmented glenoid component implantation, to reverse replacement with reaming to correct version or structural bone grafting or metallic augmentation of the bone deficiency. Shoulder replacement with severe glenoid bone loss is technically challenging and characterised by higher rates of complications and revisions. Hemiarthroplasty has limited benefit for pain relief and function especially if eccentric glenoid wear exists. Bone loss with >15 degrees of retroversion likely requires version correction include bone-grafting, augmented glenoid components, or reverse total shoulder replacement. Asymmetric reaming may improve version but is limited to 15 degrees of version correction in order to preserve subchondral bone and glenoid bone vault depth. Bone-grafting of glenoid wear and defects has had mixed results with graft-related complications, periprosthetic radiolucent lines, and glenoid component failure of fixation. Implantation of an augmented wedge or step polyethylene glenoid component improves joint version while preserving subchondral bone, but is technically demanding and with minimal short term clinical follow-up. A Mayo study demonstrated roughly 50% of patients with posteriorly augmented polyethylene had radiolucent lines and 1/3 had posterior subluxation. Another wedge polyethylene design had 66% with bone ingrowth around polyethylene fins at 3 years. Long term outcomes are unknown for these new wedge augmented glenoid components. Reverse shoulder arthroplasty avoids many risks of anatomic replacement glenoid component fixation and stability but is associated with a high complication rate (15%) including neurologic and baseplate loosening and often requires structural bone grafting behind the baseplate with suboptimal outcomes or metallic augmented baseplates with limited evidence and short term outcomes. Reverse replacement with baseplate bone grafting or metal augmentation is technically challenging due to limited native glenoid bone stock available for baseplate component ingrowth and long term fixation. Failure to correct glenoid superior inclination and restore neutral version within 10 degrees increases the risks of reverse baseplate failure of fixation, pull out, and failure of reverse replacement. Reverse baseplate failure rates in patients with severe glenoid bone loss and concomitant glenoid bone grafting range from 5–11%. The minimum native glenoid bony contact with the baseplate is unknown but likely is approximately 1cm of native bone contacting a central ingrowth post and a minority (∼15–25%) of native glenoid contacting the backside of the baseplate. Failure to correct posterior bone loss can lead to retroversion of the baseplate, reduced external rotation, posterior scapular notching, and posteromedial polyethylene wear. In summary, shoulder replacement with severe glenoid bone loss is technically challenging and characterised by higher rates of complication and revision

Introduction. We have been re-evaluating patellofemoral alignment after total knee arthroplasty (TKA) by using a weight- bearing axial radiographic view after detecting patellar maltracking (lateral tilt > 5° or lateral subluxation > 5 mm) on standard non-weight-bearing axial radiographs. However, it is unclear whether the patellar component shape affects this evaluation method. Therefore, we compared 2 differently shaped components on weight-bearing axial radiographs. Methods. From 2004 to 2013, 408 TKAs were performed with the same type of posterior-stabilized total knee implant at our hospital. All patellae were resurfaced with an all-polyethylene, three-pegged component to restore original thickness. Regarding patellar component type, an 8-mm domed component was used when the patella was so thin that a 10-mm bone cut could not be performed. Otherwise, a 10-mm medialized patellar component was selected. Twenty-five knees of 25 patients, in whom patellar maltracking was noted on standard axial radiographs at the latest follow-up, were included in this study. Knees were divided into 2 groups: 15 knees received a medialized patella (group M) while 10 received a domed patella (group D). Weight-bearing axial radiographs with patients in the semi-squatting position were recorded with the method of Baldini et al. Patellar alignment (tilt and subluxation) was measured according to the method described by Gomes et al. using both standard and weight-bearing axial views. Results. Patients’ demographic data, such as age at surgery, sex, and disease were similar for both groups. The average follow-up period was significantly longer in group D than group M (5.4 years vs. 2.5 years, respectively; p = 0.0045, Mann- Whitney U-test). The lateral tilt angle decreased significantly (p < 0.0001, paired t-test) from 6.5° ± 2.8° to 1.0° ± 1.2° with weight bearing in group M. However, this parameter in group D changed from 6.7° ± 2.7° to 4.7° ± 3.0° with weight bearing; the difference was not significant. Lateral subluxation also decreased significantly (p < 0.0001, paired t-test) from 5.1 mm ± 2.4 mm to 2.5 mm ± 1.4 mm with weight bearing in group M. However, that in group D changed from 2.8 mm ± 2.7 mm to 2.4 mm ± 2.8 mm with weight bearing, and the difference was not significant. On weight-bearing views, patellar maltracking was noted in 4 knees in group D but no knees in group M. The difference was significant (p = 0.017, Fisher's exact test). One of the 21 patients with adequate patellar tracking (4.8%) and 1 of 4 patients with maltracking (25%) complained of mild anterior knee pain. Discussion. Patellar tracking on axial radiographic views improved better in group M than in group D with weight bearing. The patellofemoral contact area was maintained with a domed patella despite tilting, but not with a medialized patella. Our results indicate that the shape difference affected the degree of radiographic improvement. Thus, the weight-bearing axial radiographic view devised by Baldini et al. is useful for evaluating patellofemoral alignment after TKA, but the shape of the patellar component should be considered for result interpretation