Aims. Despite the expansion of arthroscopic surgery of the shoulder, the open deltopectoral approach is increasingly used for the fixation of fractures and arthroplasty of the shoulder. The anatomy of the terminal branches of the posterior circumflex humeral artery (PCHA) has not been described before. We undertook an investigation to correct this omission. Patients and Methods. The vascular anatomy encountered during 100 consecutive elective deltopectoral approaches was recorded, and the common variants of the terminal branches of the PCHA are described. Results. In total, 92 patients (92%) had a terminal branch that crossed the space between the deltoid and the proximal humerus and which was therefore vulnerable to tearing or avulsion during the insertion of the blade of a retractor during the deltopectoral approach to the shoulder. In 75 patients (75%) there was a single vessel, in 16 (16%) a double vessel and in one a triple vessel. Conclusion. The relationship of these vessels to the landmark of the tendon of the insertion of pectoralis major into the proximal humerus is described. Damage to these previously undocumented branches can cause persistent bleeding leading to prolonged surgery and post-operative haematoma and infection, as well as poor visualisation during the procedure. Cite this article: Bone Joint J 2016;98-B:1395–8

The piriformis muscle is an important landmark in the surgical anatomy of the hip, particularly the posterior approach for total hip replacement (THR). Standard orthopaedic teaching dictates that the tendon must be cut in to allow adequate access to the superior part of the acetabulum and the femoral medullary canal. However, in our experience a routine THR can be performed through a posterior approach without sacrificing this tendon. We dissected the proximal femora of 15 cadavers in order to clarify the morphological anatomy of the piriformis tendon. We confirmed that the tendon attaches on the crest of the greater trochanter, in a position superior to the trochanteric fossa, away from the entry point for broaching the intramedullary canal during THR. The tendon attachment site encompassed the summit and medial aspect of the greater trochanter as well as a variable attachment to the fibrous capsule of the hip joint. In addition we dissected seven cadavers resecting all posterior attachments except the piriformis muscle and tendon in order to study their relations to the hip joint, as the joint was flexed. At flexion of 90° the piriformis muscle lay directly posterior to the hip joint. The piriform fossa is a term used by orthopaedic surgeons to refer the trochanteric fossa and normally has no relation to the attachment site of the piriformis tendon. In hip flexion the piriformis lies directly behind the hip joint and might reasonably be considered to contribute to the stability of the joint. We conclude that the anatomy of the piriformis muscle is often inaccurately described in the current surgical literature and terms are used and interchanged inappropriately. Cite this article: Bone Joint J 2013;95-B:764–9

Anterior cruciate ligament (ACL) reconstruction is commonly performed and has been for many years. Despite this, the technical details related to ACL anatomy, such as tunnel placement, are still a topic for debate. In this paper, we introduce the flat ribbon concept of the anatomy of the ACL, and its relevance to clinical practice. Cite this article: Bone Joint J 2016;98-B:1020–6

Aims. The aim of this study was to compare robotic arm-assisted bi-unicompartmental knee arthroplasty (bi-UKA) with conventional mechanically aligned total knee arthroplasty (TKA) in order to determine the changes in the anatomy of the knee and alignment of the lower limb following surgery. Methods. An analysis of 38 patients who underwent TKA and 32 who underwent bi-UKA was performed as a secondary study from a prospective, single-centre, randomized controlled trial. CT imaging was used to measure coronal, sagittal, and axial alignment of the knee preoperatively and at three months postoperatively to determine changes in anatomy that had occurred as a result of the surgery. The hip-knee-ankle angle (HKAA) was also measured to identify any differences between the two groups. Results. The pre- to postoperative changes in joint anatomy were significantly less in patients undergoing bi-UKA in all three planes in both the femur and tibia, except for femoral sagittal component orientation in which there was no difference. Overall, for the six parameters of alignment (three femoral and three tibial), 47% of bi-UKAs and 24% TKAs had a change of < 2° (p = 0.045). The change in HKAA towards neutral in varus and valgus knees was significantly less in patients undergoing bi-UKA compared with those undergoing TKA (p < 0.001). Alignment was neutral in those undergoing TKA (mean 179.5° (SD 3.2°)) while those undergoing bi-UKA had mild residual varus or valgus alignment (mean 177.8° (SD 3.4°)) (p < 0.001). Conclusion. Robotic-assisted, cruciate-sparing bi-UKA maintains the natural anatomy of the knee in the coronal, sagittal, and axial planes better, and may therefore preserve normal joint kinematics, compared with a mechanically aligned TKA. This includes preservation of coronal joint line obliquity. HKAA alignment was corrected towards neutral significantly less in patients undergoing bi-UKA, which may represent restoration of the pre-disease constitutional alignment (p < 0.001). Cite this article: Bone Joint J 2020;102-B(11):1511–1518

Aims. Restoring the pre-morbid anatomy of the proximal humerus is a goal of anatomical shoulder arthroplasty, but reliance is placed on the surgeon’s experience and on anatomical estimations. The purpose of this study was to present a novel method, ‘Statistical Shape Modelling’, which accurately predicts the pre-morbid proximal humeral anatomy and calculates the 3D geometric parameters needed to restore normal anatomy in patients with severe degenerative osteoarthritis or a fracture of the proximal humerus. Materials and Methods. From a database of 57 humeral CT scans 3D humeral reconstructions were manually created. The reconstructions were used to construct a statistical shape model (SSM), which was then tested on a second set of 52 scans. For each humerus in the second set, 3D reconstructions of four diaphyseal segments of varying lengths were created. These reconstructions were chosen to mimic severe osteoarthritis, a fracture of the surgical neck of the humerus and a proximal humeral fracture with diaphyseal extension. The SSM was then applied to the diaphyseal segments to see how well it predicted proximal morphology, using the actual proximal humeral morphology for comparison. Results. With the metaphysis included, mimicking osteoarthritis, the errors of prediction for retroversion, inclination, height, radius of curvature and posterior and medial offset of the head of the humerus were 2.9° (± 2.3°), 4.0° (± 3.3°), 1.0 mm (± 0.8 mm), 0.8 mm (± 0.6 mm), 0.7 mm (± 0.5 mm) and 1.0 mm (± 0.7 mm), respectively. With the metaphysis excluded, mimicking a fracture of the surgical neck, the errors of prediction for retroversion, inclination, height, radius of curvature and posterior and medial offset of the head of the humerus were 3.8° (± 2.9°), 3.9° (± 3.4°), 2.4 mm (± 1.9 mm), 1.3 mm (± 0.9 mm), 0.8 mm (± 0.5 mm) and 0.9 mm (± 0.6 mm), respectively. Conclusion. This study reports a novel, computerised method that accurately predicts the pre-morbid proximal humeral anatomy even in challenging situations. This information can be used in the surgical planning and operative reconstruction of patients with severe degenerative osteoarthritis or with a fracture of the proximal humerus. Cite this article: Bone Joint J 2017;99-B:927–33

The inferior gluteal artery is described in standard anatomy textbooks as contributing to the blood supply of the hip through an anastomosis with the medial femoral circumflex artery. The site(s) of the anastomosis has not been described previously. We undertook an injection study to define the anastomotic connections between these two arteries and to determine whether the inferior gluteal artery could supply the lateral epiphyseal arteries alone. From eight fresh-frozen cadaver pelvic specimens we were able to inject the vessels in 14 hips with latex moulding compound through either the medial femoral circumflex artery or the inferior gluteal artery. Injected vessels around the hip were then carefully exposed and documented photographically. In seven of the eight specimens a clear anastomosis was shown between the two arteries adjacent to the tendon of obturator externus. The terminal vessel arising from this anastomosis was noted to pass directly beneath the posterior capsule of the hip before ascending the superior aspect of the femoral neck and terminating in the lateral epiphyseal vessels. At no point was the terminal vessel found between the capsule and the conjoined tendon. The medial femoral circumflex artery receives a direct supply from the inferior gluteal artery immediately before passing beneath the capsule of the hip. Detailed knowledge of this anatomy may help to explain the development of avascular necrosis after hip trauma, as well as to allow additional safe surgical exposure of the femoral neck and head

Despite the expansion of arthroscopic surgery of the shoulder, the open deltopectoral approach to the shoulder is still frequently used, for example in fracture fixation and shoulder replacement. However, it is sometimes accompanied by unexpected bleeding. The cephalic vein is the landmark for the deltopectoral interval, yet its intimate relationship with the deltoid artery, and the anatomical variations in that structure, have not previously been documented. In this study the vascular anatomy encountered during 100 consecutive elective deltopectoral approaches was recorded and the common variants described. Two common variants of the deltoid artery were encountered. In type I (71%) it crosses the interval and tunnels into the deltoid muscle without encountering the cephalic vein. However, in type II (21%) it crosses the interval, reaches the cephalic vein and then runs down, medial to and behind it, giving off several small arterial branches that return back across the interval to the pectoralis major. Several minor variations were also seen (8%). These variations in the deltoid artery have not previously been described and may lead to confusion and unexpected bleeding during this standard anterior surgical approach to the shoulder. Cite this article: Bone Joint J 2013;95-B:657–9

We studied the anatomy of the patellofemoral joint in the axial plane on cryosections from a cadaver knee and on MR arthrotomograms from 30 patients. The cryosections revealed differences in the geometry and anatomy of the surface of the articular cartilage and corresponding subchondral osseous contours of the patellofemoral joint. On the MR arthrotomograms the surface geometry of the cartilage matched the osseous contour of the patella in only four of the 30 knees. The articular cartilaginous surface of the intercondylar sulcus and corresponding osseous contour of the femoral trochlea matched in only seven knees. Since MR arthrotomography can distinguish between the surface geometry of the articular cartilage and subchondral osseous anatomy of the patellofemoral joint, it allows the surgeon and the radiologist to appraise the true articulating surfaces. We therefore recommend MR arthrotomography as the imaging technique of choice

Recently, gender-specific designs of total knee replacement have been developed to accommodate anatomical differences between males and females. We examined a group of male and female distal femora matched for age and height, to determine if there was a difference in the aspect ratio (mediolateral distance versus anteroposterior distance) and the height of the anterior flange between the genders. The Hamann-Todd Collection provided 1207 skeletally mature cadaver femora. The femoral length, the anteroposterior height, height of the lateral and medial flanges and the mediolateral width were measured in all the specimens. The mechanical axis of the femur, the cut articular width and the aspect ratio were assessed. Statistical analysis of the effect of gender upon the aspect ratio and the lateral and medial flanges was undertaken, controlling for age, height and race. The mean aspect ratio of male femora was 1.21 (. sd. 0.07) and of female femora it was 1.16 (. sd. 0.06) (p < 0.001). There was no significant difference between male and female specimens in the mean size of the lateral flange (6.57 mm (. sd. 2.57) and 7.02 mm (. sd. 2.36), respectively; p = 0.099) or of the medial flange (3.03 mm (. sd. 2.47) and 3.56 mm (. sd. 2.32), respectively; p = 0.67). Future work in the design of knee prostheses should take into account the overall variability of the anatomy of the distal femur

The effect of rheumatoid arthritis on the anatomy of the cervical spine has not been clearly documented. We studied 129 female patients, 90 with rheumatoid arthritis and 39 with other pathologies (the control group). There were 21 patients in the control group with a diagnosis of cervical spondylotic myelopathy, and 18 with ossification of the posterior longitudinal ligament. All had plain lateral radiographs taken of the cervical spine as well as a reconstructed CT scan. The axial diameter of the width of the pedicle, the thickness of the lateral mass, the height of the isthmus and internal height were measured. The transverse diameter of the transverse foramen (d1) and that of the spinal canal (d2) were measured, and the ratio d1/d2 calculated. The width of the pedicles and the thickness of the lateral masses were significantly less in patients with rheumatoid arthritis than in those with other pathologies. The area of the transverse foramina in patients with rheumatoid arthritis was significantly greater than that in the other patients. The ratio of d1 to d2 was not significantly different. A high-riding vertebral artery was noted in 33.9% of the patients with rheumatoid arthritis and in 7.7% of those with other pathologies. This difference was statistically significant. In the rheumatoid group there was a significant correlation between isthmus height and vertical subluxation and between internal height and vertical subluxation

In this case report a four-year-old girl with ulnar dimelia is described. She had six digits without mirror symmetry in her right hand. The first pre-axial digit was excised and true pollicisation performed for the second pre-axial digit. The arterial anatomy was abnormal but there was not symmetrical development of the arterial tree

We dissected 20 cadaver hips in order to investigate the anatomy and excursion of the trochanteric muscles in relation to the posterior approach for total hip replacement. String models of each muscle were created and their excursion measured while the femur was moved between its anatomical position and the dislocated position. The position of the hip was determined by computer navigation. In contrast to previous studies which showed a separate insertion of piriformis and obturator internus, our findings indicated that piriformis inserted onto the superior and anterior margins of the greater trochanter through a conjoint tendon with obturator internus, and had connections to gluteus medius posteriorly. Division of these connections allowed lateral mobilisation of gluteus medius with minimal retraction. Analysis of the excursion of these muscles revealed that positioning the thigh for preparation of the femur through this approach elongated piriformis to a maximum of 182%, obturator internus to 185% and obturator externus to 220% of their resting lengths, which are above the thresholds for rupture of these muscles. Our findings suggested that gluteus medius may be protected from overstretching by release of its connection with the conjoint tendon. In addition, failure to detach piriformis or the obturators during a posterior approach for total hip replacement could potentially produce damage to these muscles because of over-stretching, obturator externus being the most vulnerable

Various classifications of scaphoid fractures have been based on plain radiography, but there are difficulties in defining the actual fracture line without an appreciation of the three-dimensional anatomy. Radiological fracture lines were therefore mapped on transparent methylmethacrylate models of the bone. An analysis of 91 acute fractures showed that 11 were apparently incomplete. The other 80 showed three basic anatomical patterns: transverse through the waist, oblique in the plane of the dorsal sulcus, or of the proximal pole. There was some variation and comminution in these patterns, but no distal fractures of the body were seen. The interpretation of different radiological projections is discussed. The findings have implications for the management and the assessment of outcome

We carried out a cadaver study of 16 iliolumbar veins in order to define the surgical anatomy. Two variants were found; a single vein at a mean distance of 3.74 cm from the inferior vena cava (11 of 16) and two separate draining veins at a mean distance from the vena cava of 2.98 cm for the proximal and 6.24 cm for the distal stem (5 of 16). Consistently, the proximal vein tore on attempted medial retraction of the great vessels. The mean length of the vein was 1.6 cm and its mean width 1.07 cm. Three stems were shorter than 0.5 cm. Two or more tributaries usually drained the iliacus and psoas muscles, and the fifth lumbar vertebral body. The obturator nerve crossed all veins superficially at a mean of 2.76 cm lateral to the mouth. In four of these, this distance was less than 1.5 cm. Usually, the lumbosacral trunk crossed deep, at a mean distance of 2.5 cm lateral to the mouth, but in three veins, this distance was 1 cm or less. Our findings emphasise the need for proper dissection of the iliolumbar vein before ligature during exposure of the anterior lumbar spine

The primary source for the blood supply of the head of the femur is the deep branch of the medial femoral circumflex artery (MFCA). In posterior approaches to the hip and pelvis the short external rotators are often divided. This can damage the deep branch and interfere with perfusion of the head. We describe the anatomy of the MFCA and its branches based on dissections of 24 cadaver hips after injection of neoprene-latex into the femoral or internal iliac arteries. The course of the deep branch of the MFCA was constant in its extracapsular segment. In all cases there was a trochanteric branch at the proximal border of quadratus femoris spreading on to the lateral aspect of the greater trochanter. This branch marks the level of the tendon of obturator externus, which is crossed posteriorly by the deep branch of the MFCA. As the deep branch travels superiorly, it crosses anterior to the conjoint tendon of gemellus inferior, obturator internus and gemellus superior. It then perforates the joint capsule at the level of gemellus superior. In its intracapsular segment it runs along the posterosuperior aspect of the neck of the femur dividing into two to four subsynovial retinacular vessels. We demonstrated that obturator externus protected the deep branch of the MFCA from being disrupted or stretched during dislocation of the hip in any direction after serial release of all other soft-tissue attachments of the proximal femur, including a complete circumferential capsulotomy. Precise knowledge of the extracapsular anatomy of the MFCA and its surrounding structures will help to avoid iatrogenic avascular necrosis of the head of the femur in reconstructive surgery of the hip and fixation of acetabular fractures through the posterior approach

1. The anatomy of the forefoot in hallux valgus is compared with the normal, with a review of the literature and descriptions of anatomical preparations, observations at operation and radiographs. 2. The early and essential lesions are stretching of the ligaments on the medial side of the metatarso-phalangeal joint that attach the medial sesamoid and basal phalanx to the metatarsal, and erosion of the ridge that separates the grooves for the sesamoids on the metatarsal head. 3. In established hallux valgus a sagittal groove, formed where the cartilage is free from pressure by either the phalanx or the ligaments, cuts off a medial eminence, which articulates with the stretched ligaments, from a restricted area for the phalanx. 4. Apart from osteophytic lipping which squares off the outline of the eminence as it is seen in radiographs and a small amount of lipping of the ridge on the metatarsal there is no evidence of new bone growth. In chronic cases the eminence may degenerate or disappear. 5. The articular surfaces at the cuneo-metatarsal joint become adapted to the changed positions of the metatarsal without gross pathological change. 6. The four deep transverse ligaments that bind together the five plantar pads of the metatarso-phalangeal joints are not unduly stretched, so that as the metatarsals spread it is the ligaments that bind the pads to the heads of the metatarsals that give way. 7. The plantar metatarsal artery to the first space pursues a tortuous course between the two heads of the flexor hallucis brevis. In hallux valgus the course becomes still more tortuous and part of the pain experienced may be due to ischaemic effects

1. The pathological anatomy in a case of convex pes valgus in a patient with myelomeningocele is described. 2. A neuromuscular imbalance between the tibialis posterior and the evertors of the foot is suggested as the underlying cause of this type of foot deformity

The anatomy of 1000 symptomatic meniscus lesions is described and related to the age of the patients. All symptomatic lesions found during the study period were treated by arthroscopic surgery. Meniscal lesions were commoner in the right knee (56.5%) and 81% of the patients were men. Of the medial meniscus tears, 75% were vertical and 23% horizontal. Vertical tears of the medial meniscus occurred most often in the fourth decade and horizontal tears in the fifth. There were 22% type I, 37% type II and 31% type III vertical tears; 62% of type I tears and 23% of type II tears had locked fragments. Superior flaps were six times more common than inferior flaps. Of all medial meniscus fragments, 6% were inverted; 51% of these were flaps and the rest ruptured bucket-handle fragments. Of the lateral meniscus lesions 54% were vertical tears, 15% oblique, 15% myxoid, 4% were inverted and 5% were lesions of discoid menisci. The commonest pattern of tear in the lateral compartment (27%) was a vertical tear involving half the length and half the width of the meniscus

In order to investigate the functional anatomy of gluteus minimus we dissected 16 hips in fresh cadavers. The muscle originates from the external aspect of the ilium, between the anterior and inferior gluteal lines, and also at the sciatic notch from the inside of the pelvis where it protects the superior gluteal nerve and artery. It inserts anterosuperiorly into the capsule of the hip and continues to its main insertion on the greater trochanter. Based on these anatomical findings, a model was developed using plastic bones. A study of its mechanics showed that gluteus minimus acts as a flexor, an abductor and an internal or external rotator, depending on the position of the femur and which part of the muscle is active. It follows that one of its functions is to stabilise the head of the femur in the acetabulum by tightening the capsule and applying pressure on the head. Careful preservation or reattachment of the tendon of gluteus minimus during surgery on the hip is strongly recommended

We dissected 60 shoulders to demonstrate the anatomy of the coracohumeral ligament. The role of this structure in clinical problems of the shoulder is discussed

A new method of recording the three-dimensional anatomy of the proximal femur from a single anteroposterior radiograph is described. This technique shows that in Perthes' disease the femoral head and neck are in significant anteversion and true varus. This anatomical configuration may be important in the pathogenesis and treatment of this disorder

Aims

In patients where the proximal femur shows gross deformity due to degenerative changes or fracture, the contralateral femur is often used to perform preoperative templating for hip arthroplasty. However, femurs may not be symmetrical: the aim of this study was to determine the degree of variation between hips in healthy individuals and to determine whether it is affected by demographic parameters.

1. A method of finger dissection is described which provides a new approach to the anatomical study of structures in close relation to joints. 2. The volar part of the capsule of the finger joints is described, the attachment to the bones being particularly emphasised together with its form which is like that of a meniscus. 3. A gap between bone and tendon sheath is described. 4. Theoretical and clinical aspects of the local anatomy are discussed

Most techniques described for the correction of hallux valgus require exposure of the distal aspect of the first metatarsal. A dorsomedial incision is often recommended. Texts counsel against damaging the dorsal digital nerve, as a painful neuroma is an unwelcome surgical complication. Our study on cadavers aimed to investigate the anatomy of the dorsomedial cutaneous nerve in the metatarsophalangeal region, with special reference to surgical incisions. A constant, previously unrecognised branch of the nerve was identified. This branch is likely to be damaged if a dorsomedial approach is used. It is recommended that a mid-medial incision be used instead, i.e. at the junction of the plantar and dorsal skin

The nerve roots of the cauda equina may be visualised by contrast-enhanced CT scans and by surface-coil MRI. We have identified the pattern of anatomy from L2-L3 to L5-S1 in 10 human cadaver specimens and correlated this with anatomical dissections. Individual roots are slightly more distinct on contrast-enhanced CT than on surface-coil MRI. There is a crescentic oblique pattern of nerve roots at the lower lumbar levels which is still apparent in the more crowded proximal sections. In all cases, the axial images correlated precisely with the dissections. Current imaging modalities can help the clinical understanding and management of abnormalities in this region of the spine

The anatomy of the mortise of the Lisfranc joint between the medial and lateral cuneiforms was studied in detail, with particular reference to features which may predispose to injury. In 33 consecutive patients with Lisfranc injuries we measured, from conventional radiographs, the medial depth of the mortise (A), the lateral depth (B) and the length of the second metatarsal (C). MRI was used to confirm the diagnosis. We calculated the mean depth of the mortise (A+B)/2, and the variables of the lever arm as follows: C/A, C/B and C/mean depth. The data were compared with those obtained in 84 cadaver feet with no previous injury of the Lisfranc joint complex. Statistical analysis used Student’s two-sample t-test at the 5% error level and forward stepwise logistic regression. The mean medial depth of the mortise was found to be significantly less in patients with Lisfranc injuries than in the control group. Stepwise logistic regression identified only this depth as a significant risk factor for Lisfranc injuries. The odds of being in the injury group is 0.52 (approximately half) that of being a control if the medial depth of the mortise is increased by 1 mm, after adjusting for the other variables in the model. Our findings show that the mortise in patients with injuries to the Lisfranc joint is shallower than in the control group and the shallower it is the greater is the risk of injury

We hypothesised that a large acromial cover with an upwardly tilted glenoid fossa would be associated with degenerative rotator cuff tears (RCTs), and conversely, that a short acromion with an inferiorly inclined glenoid would be associated with glenohumeral osteoarthritis (OA). This hypothesis was tested using a new radiological parameter, the critical shoulder angle (CSA), which combines the measurements of inclination of the glenoid and the lateral extension of the acromion (the acromion index). The CSA was measured on standardised radiographs of three groups: 1) a control group of 94 asymptomatic shoulders with normal rotator cuffs and no OA; 2) a group of 102 shoulders with MRI-documented full-thickness RCTs without OA; and 3) a group of 102 shoulders with primary OA and no RCTs noted during total shoulder replacement. The mean CSA was 33.1° (26.8° to 38.6°) in the control group, 38.0° (29.5° to 43.5°) in the RCT group and 28.1° (18.6° to 35.8°) in the OA group. Of patients with a CSA > 35°, 84% were in the RCT group and of those with a CSA < 30°, 93% were in the OA group. We therefore concluded that primary glenohumeral OA is associated with significantly smaller degenerative RCTs with significantly larger CSAs than asymptomatic shoulders without these pathologies. These findings suggest that individual quantitative anatomy may imply biomechanics that are likely to induce specific types of degenerative joint disorders. Cite this article: Bone Joint J 2013;95-B:935–41

The development of the iliolumbar ligament and its anatomy and histology were studied in cadavers from the newborn to the ninth decade. The structure was entirely muscular in the newborn and became ligamentous only from the second decade, being formed by metaplasia from fibres of the quadratus lumborum muscle. By the third decade, the definitive ligament was well formed; degenerative changes were noted in older specimens. The iliolumbar ligament may have an important role in maintaining lumbosacral stability in patients with lumbar disc degeneration, degenerative spondylolisthesis and pelvic obliquity secondary to neuromuscular scoliosis

We have studied the radiographic and CT features of 120 displaced intra-articular fractures of the calcaneum in order to define the pathological anatomy. In 96% of cases, the CT scans identified three main fragments: sustentacular, lateral joint and body. The sustentacular fragment was often rotated into varus, the lateral joint fragment into valgus and the body fragment impacted upwards, in varus and displaced laterally. The displacement of these fragments varied according to which of three fracture types was present, as defined by the composition of the fractured lateral wall of the calcaneum. In type 1 it was formed by the lateral joint fragment alone; in type 2 by both body and lateral joint fragments; and in type 3 by the body fragment alone. Fracture fragment displacement differs from that previously described, in that true uniform depression of the lateral joint fragment is rare

This work studied the fibre bundle anatomy of the anterior cruciate ligament. Three functional bundles--anteromedial, intermediate, and posterolateral--were identified in cadaver knees. Their contributions to resisting anterior subluxation in flexion and extension were found by repeated tests after sequential bundle transection. Changes of length in flexion and extension and in tibial rotation were measured. None of the fibres were isometric. The posterolateral bundle was stretched in extension and the anteromedial in flexion, which correlated with increased contributions to knee stability and the likelihood of partial ruptures in these positions. Tibial rotation had no significant effect. The fibre length changes suggested that the 'isometric point' aimed at by some ligament replacements lay anterior and superior to the femoral origin of the intermediate fibre bundle and towards the roof of the intercondylar notch

The aim of this study was to investigate the relationship between the geometry of the proximal femur and the incidence of intra-operative fracture during uncemented total hip arthroplasty (THA).

We studied the pre-operative CT scans of 100 patients undergoing THA with an uncemented femoral component. We measured the anteroposterior and mediolateral dimensions at the level of division of the femoral neck to calculate the aspect ratio of the femur. Wide variations in the shape of the femur were observed, from round, to very narrow elliptic. The femurs of women were narrower than those of men (p < 0.0001) and small femurs were also narrower than large ones. Patients with an intra-operative fracture of the calcar had smaller and narrower femurs than those without a fracture (p < 0.05) and the implanted Corail stems were smaller in those with a fracture (mean size 9 vs 12, p < 0.0001).

The variability of the shape of the femoral neck at the level of division contributes to the understanding of the causation of intra-operative fractures in uncemented THA.

Cite this article: Bone Joint J 2015;97-B:741–8.

The purpose of this study was to determine whether it would be feasible to use oblique lumbar interbody fixation for patients with degenerative lumbar disease who required a fusion but did not have a spondylolisthesis.

A series of CT digital images from 60 patients with abdominal disease were reconstructed in three dimensions (3D) using Mimics v10.01: a digital cylinder was superimposed on the reconstructed image to simulate the position of an interbody screw. The optimal entry point of the screw and measurements of its trajectory were recorded. Next, 26 cadaveric specimens were subjected to oblique lumbar interbody fixation on the basis of the measurements derived from the imaging studies. These were then compared with measurements derived directly from the cadaveric vertebrae.

Our study suggested that it is easy to insert the screws for L1/2, L2/3 and L3/4 fixation: there was no significant difference in measurements between those of the 3-D digital images and the cadaveric specimens. For L4/5 fixation, part of L5 inferior articular process had to be removed to achieve the optimal trajectory of the screw. For L5/S1 fixation, the screw heads were blocked by iliac bone: consequently, the interior oblique angle of the cadaveric specimens was less than that seen in the 3D digital images.

We suggest that CT scans should be carried out pre-operatively if this procedure is to be adopted in clinical practice. This will assist in determining the feasibility of the procedure and will provide accurate information to assist introduction of the screws.

Cite this article: Bone Joint J 2013;95-B:977–82.

While the evolution of the bony skeleton of the shoulder girdle is well described, there is little information regarding the soft tissues, in particular of the rotator cuff. We dissected the shoulders of 23 different species and compared the anatomical features of the tendons of the rotator cuff. The alignment and orientation of the collagen fibres of some of the tendons were also examined histologically. The behaviour of the relevant species was studied, with particular reference to the extent and frequency of forward-reaching and overhead activity of the forelimb.

In quadrupedal species, the tendons of supraspinatus, infraspinatus and teres minor were seen to insert into the greater tuberosity of the humerus separately. They therefore did not form a true rotator cuff with blending of the tendons. This was only found in advanced primates and in one unusual species, the tree kangaroo. These findings support the suggestion that the appearance of the rotator cuff in the evolutionary process parallels anatomical adaptation to regular overhead activity and the increased use of the arm away from the sagittal plane.

Anatomical descriptions of the lateral retinaculum have been published, but the attachments, name or even existence of its tissue bands and layers are ill-defined. We have examined 35 specimens of the knee. The deep fascia is the most superficial layer and the joint capsule is the deepest. The intermediate layer is the most substantial and consists of derivatives of the iliotibial band and the quadriceps aponeurosis. The longitudinal fibres of the iliotibial band merge with those of the quadriceps aponeurosis adjacent to the patella. These longitudinal fibres are reinforced by superficial arciform fibres and on the deep aspect by transverse fibres of the iliotibial band. The latter are dense and provide attachment of the iliotibial band to the patella and the tendon of vastus lateralis obliquus.

Our study identifies two important new findings which are a constant connection of the deep fascia to the quadriceps tendon superior and lateral to the patella, and, a connection of the deeper transverse fibres to the tendon of vastus lateralis obliquus.

1. The normal vascular anatomy of flexor tendons and extensor tendons in the hind limb of the rabbit is outlined. A marked difference between a tendon in a sheath and a tendon with a paratenon is shown, the latter having a much better blood supply. 2. The vascular reaction in flexor tendon divided within a sheath is shown. 3. The revascularisation of free grafts is illustrated and the differences between tendon with sheath and tendon with paratenon are detailed. 4. Experiments are reported to show that the microcirculation within a "vascular" tendon can support a pedicle graft in the rabbit. Such pedicle grafts are shown to be inferior to free grafts of "avascular" tendon, but the vascularity within the pedicle tendon graft may be modified by "blocking" the surface with silastic tubing. 5. The implications of this work on tendon grafting are discussed, together with a review of additional experimental work in related fields

From a search of MRI reports on knees, 20 patients were identified with evidence of early anteromedial osteoarthritis without any erosion of bone and a control group of patients had an acute rupture of the anterior cruciate ligament. The angle formed between the extension and flexion facets of the tibia, which is known as the extension facet angle, was measured on a sagittal image at the middle of the medial femoral condyle.

The mean extension facet angle in the control group was 14° (3° to 25°) and was unrelated to age (Spearman’s rank coefficient, p = 0.30, r = 0.13). The mean extension facet angle in individuals with MRI evidence of early anteromedial osteoarthritis was 19° (13° to 26°, SD 4°). This difference was significant (Mann-Whitney U test, p < 0.001).

A wide variation in the extension facet angle was found in the normal control knees and an association between an increased extension facet angle and MRI evidence of early anteromedial osteoarthritis. Although a causal link has not been demonstrated, we postulate that a steeper extension facet angle might increase the duration of loading on the extension facet during the stance phase of gait, and that this might initiate failure of the articular cartilage.

Three-dimensional surface models of the normal hemipelvis derived from volumetric CT data on 42 patients were used to determine the radius, depth and orientation of the native acetabulum. A sphere fitted to the lunate surface and a plane matched to the acetabular rim were used to calculate the radius, depth and anatomical orientation of the acetabulum. For the 22 females the mean acetabular abduction, anteversion, radius and normalised depth were 57.1° (50.7° to 66.8°), 24.1° (14.0° to 33.3°), 25 mm (21.7 to 30.3) and 0.79 mm (0.56 to 1.04), respectively. The same parameters for the 20 males were 55.5° (47.7° to 65.9°), 19.3° (8.5° to 32.3°), 26.7 mm (24.5 to 28.7) and 0.85 mm (0.65 to 0.99), respectively.

The orientation of the native acetabulum did not match the safe zone for acetabular component placement described by Lewinnek. During total hip replacement surgeons should be aware that the average abduction angle of the native acetabulum exceeds that of the safe zone angle. If the concept of the safe zone angle is followed, abduction of the acetabular component should be less than the abduction of the native acetabulum by approximately 10°.

In a series of 126 consecutive pilon fractures, we have described anatomically explicable fragments. Fracture lines describing these fragments have revealed ten types of pilon fracture which belong to two families, sagittal and coronal. The type of fracture is dictated by the energy of injury, the direction of the force of injury and the age of the patient.

Determining and accurately restoring the flexion-extension axis of the elbow is essential for functional recovery after total elbow arthroplasty (TEA). We evaluated the effect of morphological features of the elbow on variations of alignment of the components at TEA. Morphological and positioning variables were compared by systematic CT scans of 22 elbows in 21 patients after TEA.

There were five men and 16 women, and the mean age was 63 years (38 to 80). The mean follow-up was 22 months (11 to 44).

The anterior offset and version of the humeral components were significantly affected by the anterior angulation of the humerus (p = 0.052 and p = 0.004, respectively). The anterior offset and version of the ulnar components were strongly significantly affected by the anterior angulation of the ulna (p < 0.001 and p < 0.001).

The closer the anterior angulation of the ulna was to the joint, the lower the ulnar anterior offset (p = 0.030) and version of the ulnar component (p = 0.010). The distance from the joint to the varus angulation also affected the lateral offset of the ulnar component (p = 0.046).

Anatomical variations at the distal humerus and proximal ulna affect the alignment of the components at TEA. This is explained by abutment of the stems of the components and is particularly severe when there are substantial deformities or the deformities are close to the joint.

Cite this article: Bone Joint J 2015;97-B:1539–45.

We performed a series of 16 anatomical dissections on Caucasian cadaver material to determine the surgical anatomy of the medial femoral circumflex artery (MFCA) and its anastomoses. These confirmed that the femoral head receives its blood supply primarily from the MFCA via a group of posterior superior nutrient arteries and the posterior inferior nutrient artery. In terms of anastomoses that may also contribute to the blood supply, the anastomosis with the inferior gluteal artery, via the piriformis branch, is the most important. These dissections provide a base of knowledge for further radiological studies on the vascularity of the normal femoral head and its vascularity after dislocation of the hip.

The arterial supply to the flexor tendons of the fingers was studied by means of angiography, by the injection of coloured latex, and by microdissection. It was established that there were no anastomoses between the intra-osseous circulation and that of the synovial sheath. Two separate sources of blood supply to the sheath were found: the digitopalmar arches and the specific arteries of the sheath. The findings indicate that the ideal location for incision into the digital sheath is in the midline of the palmar surface. The flexor tendons within the sheath are supplied only by branches of the digitopalmar arches. Considerable differences were observed in the details of blood supply of the tendon of flexor superficialis and that of flexor profundus.

1. Evidence is presented that the basic lesion in scoliosis is relative lengthening of the anterior components of the spine compared with the posterior elements.

2. The logical treatment is to reduce this relative lengthening either by lengthening the posterior elements or shortening the anterior elements. This may be achieved by anterior lumbar wedge osteotomy or by epiphysiodesis; and correction of lumbar lordosis can improve a thoracic scoliosis.

1. Certain macroscopical and microscopical features of the tendo calcaneus of the rabbit are described and illustrated, and the vascularisation as revealed by Spalteholz clearing is presented.

2. The vessels of the epitenon are chiefly derived from proximal and distal sources.

3. The vessels of the paratenon are derived from the main arteries of the leg.

4. The two vascular systems are largely independent of each other except along one edge of the tendon by way of a mesotenon.

5. The paratenon, epitenon and mesotenon and the related vessels are comparable to those found in tendons with synovial sheaths. By inference and from evidence obtained by dissection on the living human subject it is suggested that the arrangements are similar in the human tendo calcaneus.

6. Considerable friction develops on movement between the surfaces of the paratenon and epitenon. This might be significant in pathological states of the human tendon.

Using radiography and computer tomography (CT) we studied the morphology of 83 hips in 69 Caucasian adults with osteoarthritis secondary to developmental dysplasia of the hip (DDH). A previously published series of 310 hips with primary osteoarthritis was used as a control group. According to the Crowe classification, 33 of the dysplastic hips were graded as class I, 27 as class II and 23 as class III or class IV.

The intramedullary femoral canal had reduced mediolateral and anteroposterior dimensions in all groups compared with the control group. Only in Crowe class II hips was the femoral neck-shaft angle increased. The proximal femur had more anteversion in all the developmental dysplasia of the hip groups, ranging from 2° to 80°. Templated measurement of acetabular dimensions for plain radiography closely matched measurements taken by CT.

The results of our study confirm the observations previously confined to the Japanese population.

We studied the origin of the anterior deltoid from the lateral third of the clavicle and the leading anterior edge of the acromion in 18 cadaver shoulders by anatomical and histological methods.

The main origin of the deltoid was from the superior surface of the anterior acromion, but muscle and tendinous attachments were also seen on the entire anterior surface of the acromion, its anteroinferior surface and on the whole width of the anterior surface of the clavicle.

Mock arthroscopic acromioplasty was shown to detach deltoid fibres from the anterior surfaces, leaving the superior attachment in continuity. Potentially, arthroscopic subacromial and clavicular resection can detach deltoid fibres originating from the anterior and anteroinferior surfaces of the acromion and clavicle and thus weaken the anterior deltoid.

The palmar ligaments of the wrist were dissected in 15 adult cadaver wrists and demonstrated by MRI in three. Ten fetal wrists (10 to 19 weeks' gestation) were studied in histological sections. The palmar scaphotriquetral ligament was found in them all. Its attachment to the triquetrum is substantial but that to the scaphoid is thin and fan-shaped, its fibres interdigitating with those of the radioscaphocapitate ligament. The contribution of the ligament to carpal stability has yet to be studied, but it may help to support the head of the capitate when the wrist is dorsiflexed.

Three amputated legs with tibial dysplasia were studied by radiography, arteriography and anatomical dissection. The radiographic appearances were the same as the Type 1b tibial dysplasia described by Jones, Barnes and Lloyd-Roberts (1978) in that the tibiae were absent but the lower femoral epiphyses were normal. However, our anatomical findings differed from those of Jones et al. since no bony or cartilaginous anlage of the proximal tibia was found in any of the three legs. The pattern of vascular anomaly was identical in the three legs and similar to the findings of Hootnick et al. (1980) in congenital short fibula. Congenital fusion of the subtalar joint was a constant finding. These results support the hypothesis that the arterial and skeletal systems are vulnerable to a teratogenic insult in the fifth week of embryonic life. The bony and arterial anomalies should be borne in mind by the surgeon attempting reconstructive surgery for this condition.

1. We have considered torsional deformity in club feet and conclude that medial torsion does not occur in the tibia.

2. It is suggested that in uncorrected feet the hindfoot with the ankle mortise is laterally rotated.

3. We have discussed the cause, prevention and consequences of spurious correction by lateral rotation.

4. The "bean-shaped foot" seems an appropriate description of the final deformity as it is commonly seen.

We examined 270 scapular bones and found an incidence of os acromiale of 8.2%. In most cases, the free fragment was approximately one-third of the overall length of the acromion, and included the acromioclavicular facet and the principal areas of attachment of the coracoacromial ligament. Two-thirds of the specimens showed a distinctive pattern of osteophytic lipping. Based on this study, we devised operative procedures for symptomatic patients, and operated upon seven, with good results in six.

Nuclear magnetic resonance imaging (MRI) was used to study the normal knee. As well as revealing bone quality, MRI provided useful information on intra-articular and extra-articular soft tissues. Midsagittal views gave clear images of the cruciate ligaments, and of the patellar and quadriceps tendons. Parasagittal views were the best for delineating the menisci which, like ligaments and tendons, are of low intensity; the semimembranosus tendon and its insertion to the proximal tibia were also seen clearly in these views. The cruciate ligaments and menisci, though visible in the coronal view also, were better seen in the sagittal view. Axial views provided information on the structure of the patella, its cartilage, the patellofemoral joint and posterior soft-tissue structures.

We examined 200 scapular bones for signs of degenerative changes in the coraco-acromial arch. The slope and length of the acromion and the height of the arch were found to be most closely associated with degenerative change. These anatomical features are not significantly altered by current techniques of subacromial decompression.

Dorsiflexion has been studied in three normal feet and in three feet with talipes equinovarus to determine the anatomical features which might contribute to the failure of operative treatment to correct the deformity. In the normal feet the movement of dorsiflexion was found to be essentially rotatory in nature and not simply hinging; as dorsiflexion proceeds the fibula moves forwards relative to the os calcis and the calcaneal tendon. In the club feet a posterolateral tether was found; this prevented fibular movement and blocked dorsiflexion. As a result of this study a posterior and lateral release is advocated for the operative correction of the hindfoot in a child with a club foot deformity, particularly under the age of a year.

One hundred normal fingers were dissected and arthrographs obtained by injection of a chromopaquegelatin mixture, allowing comparison between the radiographic and macroscopic configuration of the synovial capsule. Synovial recesses protruding from each side of every metacarpo-phalangeal joint were found in relation to the collateral ligaments and corresponding exactly with the site of radiological erosions. A group of bursae lying on the superficial aspect of collateral ligaments were also demonstrated. A rudimentary infra-articular meniscus was found. The results of examination of the insertions of the interossei showed differences from traditional descriptions.

The cause of rheumatoid deformity was suggested to be the rheumatoid process arising in the lateral recesses and lateral bursae, weakening the collateral ligaments, which give way in the directions of the deforming forces. These are derived from the long flexor tendons, which were shown to exert an ulnar and volar strain on the metacarpo-phalangeal joint of every finger during grip.

1. The lesions chiefly responsible for persistent pain and weakness after acromio-clavicular dislocations are tears of the trapezius and deltoid muscles.

2. These tears cannot be adequately treated except by open operation.

3. There are often physical barriers making closed manipulative reduction impossible.

4. Open reduction and repair of torn ligaments and muscle is advocated for manual workers.

1. The form and distribution of the blood vessels within the adult human femoral head are described.

2. It has been found possible to delimit the proximal femoral epiphysis in mature years by reference to arterial form alone.

3. Two morphologically different sets of vessels are described interposed between the arterioles and venules of the bone marrow. One, a true capillary bed, lies mainly within the fat marrow; the other, constituted by sinusoids, lies within the red marrow. The departure of these findings from current views is noted.

4. A capillary system is described in relationship to the calcified zone of the articular cartilage.

5. No evidence has been found in support of the common belief that the circulation within the femoral head decreases quantitatively with advancing age.

1. The results of a study of the characteristics of the vessels found in forty-six human femoral heads during the growth period are described.

2. Of the three different sources of blood entering the human adult femoral head it was found that from birth to about three to four years the vessels of the ligamentum teres do not contribute to the nourishment of the head.

3. After the fourth year the metaphysial vessels decrease in importance until they finally disappear, leaving the head with only one source of blood through the lateral epiphysial vessels; the ligamentum teres is not yet contributing to the circulation of the head.

4. After about eight or nine years it was found that the vessels of the ligamentum teres contribute to the blood supply of the head while the metaphysial blood flow is still arrested.

5. Finally, at puberty, after a period of activity of the metaphysial vessels, epiphysial fusion takes place, bringing together the three sources of blood characteristic of the adult.

We report a prospective study of 46 patients with acute complete dislocation of the acromioclavicular joint. They were all treated by suture of the deltoid and trapezius over the clavicle with no repair of the coracoclavicular ligaments, using only temporary fixation with two wires. At operation 43 patients (93.5%) had damage to the trapezius or deltoid or both. The coracoclavicular ligaments were intact in six (13%). Follow-up was from 2 to 7.9 years (mean 5.8), and at the latest review only five patients (10.9%) had redisplacement, due to premature removal of wires for infection in one, to migration of the wires in another and to partial failure of the muscle repair in three. We consider that the deltoid and trapezius attachments are important clinical stabilizers of the clavicle and that their repair, with reinforcement, is a useful addition to any method of surgical treatment.

1. Vascular anatomical studies of the spine are described and the possibility of spread of infection from pelvis to spine through the paravertebral venous plexus is discussed.

2. Though a venous route does exist, our studies do not support the supposition that infection is likely to spread by this route; nor is there any clear clinical, pathological or anatomical evidence that such spread occurs.

3. Nineteen cases of pyogenic osteomyelitis of the spine are recorded, six of which followed urinary infections. The condition is compared with osteomyelitis as it occurs in the other bones of adults.

Cadaver knee joints were mounted so that life-like forces of weight-bearing were simulated. The patello-femoral contact areas were defined under load throughout the range of movement by the dye method. During movement from extension to 90 degrees of flexion a band of contact sweeps across the patella from inferior to superior pole, but the odd facet makes no contact. At about 135 degrees of flexion separate medial and lateral contact areas form, the medial one limited to the odd facet. From extension to 90 degrees of flexion the patella holds the quadriceps tendon away from the femur, but in further degrees of flexion an extensive "tendo-femoral" contact area forms. Between 90 degrees and 135 degrees of flexion the patella rotates and the ridge between the medial and odd facets engages the femoral condyle. The odd facet is shown to be a habitual non-contact area and the ridge to be subject to high load, observations which correlate with cartilage lesions described in Part 2 of the paper.

Direct measurements were made on 2,166 lumbar vertebrae of 433 adult negro and caucasoid skeletons. On statistical analysis, forty-five vertebrae in twenty-seven skeletons were found to be stenotic, the mid-sagittal diameter being the significantly reduced dimension. Whereas spinal stenosis syndromes are rare in South African negroes, the lumbar canal is marginally narrower in the negro. There is a uniformity of configuration and capacity of the lumbar spinal canal, which transcends race and sex. By a new method of determining the dorsal limit of the lumbar canal on lateral plain radiography, the overall average lower limit of normal of the mid-sagittal diameter is established at 15 millimetres, and of the transverse diameter 20 millimetres. Bony degenerative changes are more likely to cause neurological compression in the nerve root tunnel than in the spinal canal. The role of skeletal narrowing of the spinal canal as an exclusive cause of the spinal stenosis syndrome may have been exaggerated.

Injuries to the quadriceps muscle group are common in athletes performing high-speed running and kicking sports. The complex anatomy of the rectus femoris puts it at greatest risk of injury. There is variability in prognosis in the literature, with reinjury rates as high as 67% in the severe graded proximal tear. Studies have highlighted that athletes can reinjure after nonoperative management, and some benefit may be derived from surgical repair to restore function and return to sport (RTS). This injury is potentially career-threatening in the elite-level athlete, and we aim to highlight the key recent literature on interventions to restore strength and function to allow early RTS while reducing the risk of injury recurrence. This article reviews the optimal diagnostic strategies and classification of quadriceps injuries. We highlight the unique anatomy of each injury on MRI and the outcomes of both nonoperative and operative treatment, providing an evidence-based management framework for athletes. Cite this article: Bone Joint J 2023;105-B(12):1244–1251

Aims. The Exeter V40 femoral stem is the most implanted stem in the National Joint Registry (NJR) for primary total hip arthroplasty (THA). In 2004, the 44/00/125 stem was released for use in ‘cement-in-cement’ revision cases. It has, however, been used ‘off-label’ as a primary stem when patient anatomy requires a smaller stem with a 44 mm offset. We aimed to investigate survival of this implant in comparison to others in the range when used in primary THAs recorded in the NJR. Methods. We analyzed 328,737 primary THAs using the Exeter V40 stem, comprising 34.3% of the 958,869 from the start of the NJR to December 2018. Our exposure was the stem, and the outcome was all-cause construct revision. We stratified analyses into four groups: constructs using the 44/00/125 stem, those using the 44/0/150 stem, those including a 35.5/125 stem, and constructs using any other Exeter V40 stem. Results. In all 328,737 THAs using an Exeter V40 stem, the revision estimate was 2.8% (95% confidence interval (CI) 2.7 to 2.8). The 44/00/125 stem was implanted in 2,158 primary THAs, and the ten-year revision estimate was 4.9% (95% CI 3.6 to 6.8). Controlling for age, sex, year of operation, indication, and American Society of Anesthesiologists grade demonstrated an increased overall hazard of revision for constructs using the 44/00/125 stem compared to constructs using other Exeter V40 femoral stems (hazard ratio 1.8 (95% CI 1.4 to 2.3)). Conclusion. Although the revision estimate is within the National Institute for Health and Care Excellence ten-year benchmark, survivorship of constructs using the 44/00/125 stem appears to be lower than the rest of the range. Adjusted analyses will not take into account ‘confounding by indication’, e.g. patients with complex anatomy who may have a higher risk of revision. Surgeons and patients should be reassured but be aware of the observed increased revision estimate, and only use this stem when other implants are not suitable. Cite this article: Bone Joint J 2023;105-B(5):504–510

The December 2023 Knee Roundup. 360. looks at: Obesity is associated with greater improvement in patient-reported outcomes following primary total knee arthroplasty; Does mild flexion of the femoral prosthesis in total knee arthroplasty result in better early postoperative outcomes?; Robotic or manual total knee arthroplasty: a randomized controlled trial; Patient-relevant outcomes following first revision total knee arthroplasty, by diagnosis: an analysis of implant survivorship, mortality, serious medical complications, and patient-reported outcome measures using the National Joint Registry data set; Sagittal alignment in total knee arthroplasty: are there any discrepancies between robotic-assisted and manual axis orientation?; Tourniquet use does not impact recovery trajectory in total knee arthroplasty; Impact of proximal tibial varus anatomy on survivorship after medial unicondylar knee arthroplasty; Bone cement directly to the implant in primary total knee arthroplasty?; Maintaining joint line obliquity optimizes outcomes in patients with constitutionally varus knees

Aims. This study aimed to evaluate if total knee arthroplasty (TKA) femoral components aligned in either mechanical alignment (MA) or kinematic alignment (KA) are more biomimetic concerning trochlear sulcus orientation and restoration of trochlear height. Methods. Bone surfaces from 1,012 CT scans of non-arthritic femora were segmented using a modelling and analytics system. TKA femoral components (Triathlon; Stryker) were virtually implanted in both MA and KA. Trochlear sulcus orientation was assessed by measuring the distal trochlear sulcus angle (DTSA) in native femora and in KA and MA prosthetic femoral components. Trochlear anatomy restoration was evaluated by measuring the differences in medial, lateral, and sulcus trochlear height between native femora and KA and MA prosthetic femoral components. Results. Femoral components in both MA and KA alignments exhibited a more valgus DTSA compared to native femora. However, DTSA deviation from native was significantly less in KA than in MA (4.8° (SD 2.2°) vs 8.8° (SD 1.8°); p < 0.001). DTSA deviation from native orientation correlated positively with the mechanical lateral distal femoral angle (mLDFA) in KA and negatively in MA (r = 0.53, p < 0.001; r = -0.18, p < 0.001). Medial trochlear height was not restored with either MA or KA, with MA resulting in lower medial trochlear height than KA in the proximal 20% of the trochlea. Lateral and sulcus trochlear height was not restored with either alignment in the proximal 80% of the trochlea. At the terminal arc point, KA replicated sulcus and lateral trochlear height, while MA led to over-restoration. Conclusion. Femoral components aligned in KA demonstrated greater biomimetic qualities than those in MA regarding trochlear sulcus orientation and trochlear height restoration, particularly in valgus femora. Variability across knees was observed, warranting further research to evaluate the clinical implications of these findings. Cite this article: Bone Joint J 2024;106-B(8):817–825

Aims. The Chopart joint complex is a joint between the midfoot and hindfoot. The static and dynamic support system of the joint is critical for maintaining the medial longitudinal arch of the foot. Any dysfunction leads to progressive collapsing flatfoot deformity (PCFD). Often, the tibialis posterior is the primary cause; however, contrary views have also been expressed. The present investigation intends to explore the comprehensive anatomy of the support system of the Chopart joint complex to gain insight into the cause of PCFD. Methods. The study was conducted on 40 adult embalmed cadaveric lower limbs. Chopart joint complexes were dissected, and the structures supporting the joint inferiorly were observed and noted. Results. The articulating bones exhibit features like a cuboid shelf and navicular beak, which appear to offer inferior support to the joint. The expanse of the spring ligament complex is more medial than inferior, while the superomedial part is more extensive than the intermediate and inferoplantar parts. The spring ligament is reinforced by the tendons in the superomedial part (the main tendon of tibialis posterior), the inferomedial part (the plantar slip of tibialis posterior), and the master knot of Henry positioned just inferior to the gap between the inferomedial and inferoplantar bundles. Conclusion. This study highlights that the medial aspect of the talonavicular articulation has more extensive reinforcement in the form of superomedial part of spring ligament and tibialis posterior tendon. The findings are expected to prompt further research in weightbearing settings on the pathogenesis of flatfoot. Cite this article: Bone Jt Open 2024;5(4):335–342

Anterior cruciate ligament (ACL) injuries are among the most common and debilitating knee injuries in professional athletes with an incidence in females up to eight-times higher than their male counterparts. ACL injuries can be career-threatening and are associated with increased risk of developing knee osteoarthritis in future life. The increased risk of ACL injury in females has been attributed to various anatomical, developmental, neuromuscular, and hormonal factors. Anatomical and hormonal factors have been identified and investigated as significant contributors including osseous anatomy, ligament laxity, and hamstring muscular recruitment. Postural stability and impact absorption are associated with the stabilizing effort and stress on the ACL during sport activity, increasing the risk of noncontact pivot injury. Female patients have smaller diameter hamstring autografts than males, which may predispose to increased risk of re-rupture following ACL reconstruction and to an increased risk of chondral and meniscal injuries. The addition of an extra-articular tenodesis can reduce the risk of failure; therefore, it should routinely be considered in young elite athletes. Prevention programs target key aspects of training including plyometrics, strengthening, balance, endurance and stability, and neuromuscular training, reducing the risk of ACL injuries in female athletes by up to 90%. Sex disparities in access to training facilities may also play an important role in the risk of ACL injuries between males and females. Similarly, football boots, pitches quality, and football size and weight should be considered and tailored around females’ characteristics. Finally, high levels of personal and sport-related stress have been shown to increase the risk of ACL injury which may be related to alterations in attention and coordination, together with increased muscular tension, and compromise the return to sport after ACL injury. Further investigations are still necessary to better understand and address the risk factors involved in ACL injuries in female athletes. Cite this article: Bone Jt Open 2024;5(2):94–100

Aims. Rates of reverse total shoulder arthroplasty (rTSA) continue to grow. Glenoid bone loss and deformity remains a technical challenge to the surgeon and may reduce improvements in patients’ outcomes. However, there is no consensus as to the optimal surgical technique to best reconstruct these patients’ anatomy. This review aims to compare the outcomes of glenoid bone grafting versus augmented glenoid prostheses in the management of glenoid bone loss in primary reverse total shoulder arthroplasty. Methods. This systematic review and meta-analysis evaluated study-level data in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. We performed searches of Medline (Ovid), Embase (Ovid), and PubMed from their dates of inception to January 2022. From included studies, we analyzed data for preoperative and postoperative range of motion (ROM), patient-reported functional outcomes, and complication rates. Results. A total of 13 studies (919 shoulders) were included in the analysis. The mean age of patients at initial evaluation was 72.2 years (42 to 87), with a mean follow-up time of 40.7 months (24 to 120). Nine studies with 292 rTSAs evaluated the use of bone graft and five studies with 627 rTSAs evaluated the use of augmented glenoid baseplates. One study was analyzed in both groups. Both techniques demonstrated improvement in patient-reported outcome measures and ROM assessment, with augmented prostheses outperforming bone grafting on improvements in the American Shoulder and Elbow Surgeons Score. There was a higher complication rate (8.9% vs 3.5%; p < 0.001) and revision rate among the bone grafting group compared with the patients who were treated with augmented prostheses (2.4% vs 0.6%; p = 0.022). Conclusion. This review provides strong evidence that both bone graft and augmented glenoid baseplate techniques to address glenoid bone loss give excellent ROM and functional outcomes in primary rTSA. The use of augmented base plates may confer fewer complications and revisions. Cite this article: Bone Joint J 2022;104-B(12):1334–1342