Aims. To evaluate how fore- and midfoot coronal plane alignment differs in feet with hallux valgus (HV), using 3DCT when measured in standard weightbearing (SWB) versus sesamoid view (SV) position, and to determine whether first metatarsophalangeal (MTP) dorsiflexion affects the relationship between the first metatarsal (M1) head and the sesamoid bones. Methods. A consecutive series of 34 feet that underwent 3DCT in SWB and SV positions for symptomatic HV was assessed, of which four feet were excluded for distorted or incomplete images. Two foot and ankle clinicians independently digitized a series of points, and measured a series of angles according to a pre-defined protocol. Measurements include navicular pronation angle, M1 head (Saltzman angle), and metatarsosesamoid rotation angle (MSRA). Results. The mean age of the 30 patients was 57.5 years (SD 13.4). The mean navicular pronation angle was significantly smaller in the SV position (9.6° (SD 4.4°)) compared to the SWB position (16.4° (SD 5.8°); p < 0.001). There was a difference in MSRA between the SWB and SV positions, revealing an increase in MSRA in 22 patients, while there was a decrease in eight patients. In patients where the MSRA increased, the mean Saltzman angle was 2.5° (SD 5.7°) lower in the SV position versus the SWB position, while in patients where MSRA decreased, the mean Saltzman angle was 3.4° (SD 3.6°) greater in the SV position versus the SWB position. Conclusion. MTP dorsiflexion causes supination of the navicular, while other first ray parameters remain unchanged, and has a greater influence on the M1 head coronal alignment than on the sesamoids. MTP dorsiflexion induces axial rotations of M1, which vary in direction and magnitude from one patient to another. Cite this article: Bone Joint Res 2025;14(2):69–76

In hallux valgus (HV), toe pronation is frequently seen, although there may be some with no pronation. Aims. to evaluate big toe pronation in patients with HV with a clinical and radiographic method. Material and methods. prospective study of 40 patients with HV on the waiting list for surgical treatment. Patients were standing barefoot on a rigid platform. Digital photographs were taken in a frontal plane to obtain the nail-floor angle formed by the secant line of toenail border and a line formed by the platform edge. All patients were evaluated using the AOFAS for HV and lesser toes, if they were affected. Personal and social data were obtained from clinical interviews. Charge radiographs were used to obtain HV, intermetatarsal and PASA angles, first metatarsal rotation as well as sesamoid bones displacement. Exclusion criteria: rheumatoid arthritis and previous intervention on foot or toes. Statistical analysis were performed with a multiple lineal regression. Results. the mean age was 57 years old, they were 31 female and 9 men, with an average AOFAS score of 49, they had a mean of 37° HV angle, 27° nail-floor angle, 20° first metatarsal rotation in about half of patients. We have found a statistical significant relation between HV and nail-floor angles (p<0,001), between sesamoid bones displacement and nail-floor angles (p<0,007), between first metatarsal rotation and HV angle (p<0,001. We found no statistically significant but strong relation between first metatarsal rotation and sesamoid bones displacement. Conclusion. nail-floor angle is strongly related to degree of HV, displacement of sesamoid bones and rotation of the first metatarsal

The incidence of tarsal coalitions (TC) is not known. Most of the clinical studies report it as less then 1% but they disregard the asymptomatic coalitions. Two main theories have been elaborated regarding their etiology: 1) they result by incorporation of accessory bones into the nearby tarsals; 2) they occur as a result of the failure of differentiation and segmentation of the foetalmes-enchyme. Tarsal coalitions have been associated with degenerative arthritic changes. Computer tomography is the most commonly used diagnostic test in the detection of TC. The aims of our study were to establish the incidence of TC; the association between TC and accessory tarsal bones and between TC and tarsal arthritis; and to assess the sensitivity of CT as a diagnostic tool in TC. For this purpose we have undertaken coronal and sagittal CTs of 114 cadaveric feet which were subsequently dissected. The dissections identified 10 non-osseous tarsal coalitions, two talocalcaneal and eight calcaneonavicular. In nine cases we identified a synovial joint between the calcaneus and the navicular. We identified eight os trigonum, one accessory lateral malleolus bone, 38 sesamoid bones in the tendon of tibialis posterior and 19 sesamoid bones in the tendon of fibularis longus. Tarsal arthritis was identified in 37 cases. Both talocalcaneal coalitions were associated with talocal-caneal arthritis while none of the calcaneonavicular coalitions were associated with tarsal arthritis. The CT examination of five of the cases of calcaneonavicular coalitions showed one coalition and was suspicious of a coalition in another two instances. In conclusion our study demonstrated that the incidence of tarsal coalition is higher than previously thought (8.8%). The calcaneonavicular coalitions are more common (7%) but they do not seem to be associated with arthritic changes in the tarsal bones. The 7.9% of the calcaneonavicular synovial joint demonstrate that the “abnormality” of the calcaneonavicular space can take any form. Our preliminary CT results demonstrate a low sensitivity in the detection of nonosseous coalitions

Non-operative management of displaced olecranon fractures in elderly low demand patients is reported to result in a satisfactory outcome despite routinely producing a nonunion. The aim of this study was to assess whether there is evidence of dynamic movement of the fracture fragment during the elbow arc of movement. Five consecutive patients (≥70 years of age) with a displaced olecranon fracture (Mayo 2A) that were managed with non-operative intervention were recruited. All underwent ultrasound evaluation at six weeks and follow-up questionnaires at six months including the DASH and Oxford Elbow Score (OES). There were three women and two men with a mean age of 79yrs (range 70–88). All injuries were sustained following a fall from standing height. The mean fracture gap in extension was 22.5mm (95% CI 13.0–31.9), midflexion 21.8mm (11.6–32.0) and in deep flexion 21.8mm (10.9–32.8). Although the amount of fracture displacement varied between patients, it remained static in each patient with no significant differences observed throughout the arc of motion (ANOVA p=0.99). The six-month median DASH score was 7.5 (IQR range, 4.2–39.3) and the OES was 44.0 (29.0–47.5). Four out of the five patients were satisfied with their function. Ultrasound evaluation of displaced olecranon fractures following non-operative management suggests the proximal fragment may function as a sesamoid type bone within the triceps sleeve. This could explain how a functional arc of movement with a minimum level of discomfort can usually be expected with non-operative management in select patients

Bizarre parosteal osteochondromatous proliferation (BPOP), or Nora's lesion, is a rare condition characterised by the formation of surface-based osteocartilaginous lesions typically affecting the hands and feet. 22 cases were identified from the records of a regional bone tumour unit, dating from 1985 to 2009. Of 22 cases, 9 lesions involved the long bones of the hand, 7 the long bones of the feet, 1 case originated from a sesamoid bone of the foot and 5 from long bones (radius, ulna, femur [2] and tibia). Age ranged from 6 to 66 (mean: 31.8) and male to female ratio was 1.8:1. Diagnosis was based on combined radiological and histological features, and initial surgical treatment was excision in 21 cases, and 1 amputation. Follow-up ranged from 12–162 months (mean 32). Recurrence occurred in 6 patients (27%), with mean time to recurrence 49 months (range 10–120). 2 of 8 patients with complete resection margins developed recurrence (25%), versus 4 of 14 with marginal or incomplete resection (28%). Given the potential surgical morbidity inherent in resection, our data suggest that there may be a role for a relatively tissue-conserving approach to the excision of these lesions

Introduction. The pathogenesis of primary knee osteoarthritis is due to excess mechanical loading of the articular cartilage. Previous studies have assessed the impact of muscle forces on tibiofemoral kinematics and force distribution. A cadaveric study was performed to evaluate the effect of altering the moment arm of the iliotibial band (ITB) on knee biomechanics. Method. A robotic system consisting of a 6-DOF manipulator capable of measuring forces on the medial and lateral condyle of a cadaveric knee at various flexion angles and muscle forces was utilized [1]. The system measured the compartment forces at flexion angles between 0° and 30° under 3 simulated loading conditions (300N quadriceps, 100N hamstrings and: i. 0N ITB; ii. 50N ITB; iii. 100N ITB). Eight fresh frozen human cadaver knee specimens (4 males, 4 females); age range 36 – 50 years; weight range 49 – 90 kg; height range 154 – 190 cm were used in the study. The ITB and associated lateral soft tissue structures were laterally displaced from the lateral femoral condyle by fixing a metal implant (like in Figure 1) to the distal lateral femur. Mechanical loads on the medial and lateral compartments (with and without the implant) were measured using piezoelectric pressure sensors. Results. For each specimen, lateral displacement of the ITB due to the implant was measured (15 – 20 mm). The % average unloading of the medial compartment for all the specimens ranged from 34% – 65% (Figure 2). Also observed was a concomitant increase in lateral compartment load. Medial unloading was even observed with no ITB force (0N) which indicates a role for other lateral structures attached to the ITB in unloading the medial compartment [2]. In addition, under these non-weight bearing conditions, on average, there was an increase in valgus tibial angulation through the flexion range. Discussion. Increasing mechanical leverage of muscles across a joint is accomplished in nature through sesamoid bones (e.g., patella) which increase the muscle moment arm. By increasing the moment arm of the ITB and lateral soft tissue structures by lateralizing these structures, our model demonstrates a 34–65% unloading of the medial compartment. Studies of knee braces and weight loss have shown that reducing mechanical load on the medial condyle by even 10% provides clinical benefits in terms of reduced pain and improved function. Based on the results of this study, unloading the medial compartment by displacing the ITB laterally may be a means of treating medial osteoarthritis (Figure 3). A prospective, multi-center, non-randomized, open label, single-arm study is currently underway to establish the safety and efficacy of providing medial osteoarthritis pain relief by displacing the ITB using Cotera, Inc.'s Latella™ Knee Implant

The patella is a complex sesamoid bone within the quadriceps enhancing mechanical advantage of the extensor mechanism. Depending on activity, the patella magnifies either force or displacement; behaving as a lever, by redirecting quadriceps force it also acts as a pulley. Aim. We describe and validate a device for obtaining consistent dynamic weight bearing views of the patellofemoral joint (PFJ). Materials and Methods. Weight bearing (WB) axial views of 48 knees (24 patients) were performed using the device. The sulcus angle (SA), congruence angle (CA), lateral patellofemoral angle (LPFA), facet angle (FA) and patellofemoral displacement (PD) were measured. These were compared with similar measurements made on prone (PR) and axial (AX) radiographs of same knees. Results. Variance (V=SD2) and Standard error of mean (SEM/95% CI) for all measurements in each of the three views were analysed. For the Sulcus Angle, Congruence angle and LPFA, the WB view had the lowest SEM and the least variance in comparison to PR and AX views (SEM 1.05/V 30.14, SEM 2.52/V 172.39 and SEM 1.34/V 47.61 respectively for the SA, SEM 3.09/V 256, SEM 2.79/V 210.25 and SEM 3.37/V 306.25 respectively for the CA, SEM 0.67/V 11.9, SEM 1.20/V39.06 and SEM 1.03/V 28.83 respectively for the LPFA). SEM and Variance for FA measurements were similar for WB and AX views but superior to PR views (SEM 1.62/V 70.56, SEM 1.6/V 68.9 and SEM 2.3/V 148.84 respectively). Mean PFD was maximum on the WB view compared to the PR and AX views (36.0, −45.62 and 22.23 respectively) with lowest SEM and V (SEM 8.73/V 2052.0, SEM 18.65/V 92959.67 and SEM 9.70/V 2540.16 respectively). Conclusion. The WB view as introduced and reported here has consistently lower Variance, SEM and SD in comparison to Axial and Prone views for all measurements of the PFJ. WB view also gives a more accurate dynamic measure of Patello Femoral displacement. The view is easily obtained and readily reproduced

Forefoot reconstructive surgery can be complex and intricate, and even though performed by orthopaedic surgeons, it can be delicate, too. Despite the most ingenious techniques, patients routinely walk (stomp) all over this work, and the resulting forces applied to the foot have been extensively studied in gait analysis laboratories. But the everyday clinical challenge is how to employ durable reconstructive techniques, and how to salvage these case when they fail?. Hallux valgus surgery is replete with complications of malunion, non-union, over-correction and recurrence. Salvage often requires a revision of the patient’s expectations in addition to another surgery. First metatarso-phalangeal joint (MTP) arthrodesis, which has been demonstrated to have excellent functional outcomes, including return to sports activities, is an excellent salvage technique. Failed first MTP arthroplasty leaves a large bone defect, both in the metatarsal and phalanx. Salvage by arthrodesis requires bone grafting, rigid internal fixation, and long healing times. Tricortical iliac graft can be used to enhance restoration of length. Associated meta-tarsalgia may persist due to shortening of the first ray. Lesser metatarsal salvage sometimes can be accomplished with distal metaphyseal osteotomy. Some cases previously treated with a pan-metatarsal head resection can now be successfully salvaged by using these osteotomies to shorten multiple metatarsals. Meticulous technique is an advantage. First MTP arthrodesis itself can be complicated. One uncommonly recognized problem is the painful pressure under the residual sesamoid bone following an otherwise successful fusion. This is caused by arthritic enlargement of the sesamoid, and should be anticipate, and prevented by sesamoidectomy. Surgical technique for obtaining ideal position of the hallux will be presented. The distinction between true recurrence of interdigital (Morton’s) neuroma, and metatarsalgia can be subtle. The cause of failed neuroma surgery is as frequently an error in patient selection as it is failure of surgical technique. Case presentations will be employed to illustrate forefoot salvage principles

Adolescent hallux valgus is a progressive deformity of childhood. Patients with this disorder complain of pain, deformity, redness at the site of deformity, shoewear limitation and altered cosmesis. Surgery to correct the bunion is considered as pain gets worst, deformity increases or significant shoe wear limitation is present. However, there is still not an uniformly satisfying surgical treatment for the adolescent hallux valgus. This kind of surgery has been often associated with a high rate of recurrence and poor results. The adolescent condition often includes significant metatarsus primus varus as a primary element. This is the reason why isolated soft tissue procedures frequently fail. Surgical treatment often combines first metatarsal osteotomy with a soft tissue realignement of the first metatarsal phalangeal joint. Simmonds and Menelaus in 1960 reported their results with an osteotomy of the base of the first metatarsal in addition to McBride’s soft tissue recostruction. The procedure addresses the three main components of the adolescent hallux valgus deformity: the medial eminence, the hallux valgus and the metatarsus primus varus. Although Simmonds and Menelaus did not use any internal fixation to fix the osteotomy site, they performed a complete transverse osteotomy at the base of the first metatarsus. Besides they used an immobilization for six weeks in the post operative period. We describe a modified procedure where the osteotomy is performed incompletely at the base of the first metatarsal bone and we shortened the post operative immobilization period with a cast for three weeks. Simmonds’ procedure does not interfere with the sesamoid bones while in our method a repositioning of the sesamoids below the metatarsal head has been performed. Materials and methods: From 1997 to 2000, 22 feet in 12 female and 1 male patients were treated surgically with the modified Simmonds-Menelaus bunion procedure. A primary operation was performed on all feet treated. The average age at surgery was 12.4 years (range 10.5 – 14.6 years). Preoperative, postoperative and final follow up evaluation included history, physical examination, record of range of motion of the first metatarsophalangeal joint, anteroposterior and lateral radiograph of the feet in the weight bearing position. Results: Lenght of follow up averaged 3.9 years. The average pre operative Hallux Valgus Angle (HVA) was 31.2°. The average pre operative Inter Metatarsal Angle ( IMA) was 13.5°. The average HVA was reduced to 17.8°; the IMA was reduced to 11.3°. Of the 22 feet with preoperative subluxation of the sesamoids, all feet were improved after operation and none were worse. In order to assess our outcomes we used the duPont bunion rating score, which incorporates objective and subjective criteria. We had 5 excellent and 17 good results. There were no fair or poor results. Conclusion: Our proposed modified procedure is easy to perform and does not need any internal fixation device. The complications linked to the use of the hardware are removed. Our proposed procedure does not interfere with the shape or the length of the first metatarsal and does not preclude the possibility of further surgical correction

Objectives

Little is known about tissue changes underlying bone marrow lesions (BMLs) in non-weight-bearing joints with osteoarthritis (OA). Our aim was to characterize BMLs in OA of the hand using dynamic histomorphometry. We therefore quantified bone turnover and angiogenesis in subchondral bone at the base of the thumb, and compared the findings with control bone from hip OA.

Objectives

The exact aetiology and pathogenesis of microdamage-induced long bone fractures remain unknown. These fractures are likely to be the result of inadequate bone remodelling in response to damage. This study aims to identify an association of osteocyte apoptosis, the presence of osteocytic osteolysis, and any alterations in sclerostin expression with a fracture of the third metacarpal (Mc-III) bone of Thoroughbred racehorses.