Aims. The aim of this study was to explore why some calcar screws are malpositioned when a proximal humeral fracture is treated by internal fixation with a locking plate, and to identify risk factors for this phenomenon. Some suggestions can be made of ways to avoid this error. Methods. We retrospectively identified all proximal humeral fractures treated in our institution between October 2016 and October 2018 using the hospital information system. The patients’ medical and radiological data were collected, and we divided potential risk factors into two groups: preoperative factors and intraoperative factors. Preoperative factors included age, sex, height, weight, body mass index, proximal humeral bone mineral density, type of fracture, the condition of the medial hinge, and medial metaphyseal head extension. Intraoperative factors included the grade of surgeon, neck-shaft angle after reduction, humeral head height, restoration of medial support, and quality of reduction. Adjusted binary logistic regression and multivariate logistic regression models were used to identify pre- and intraoperative risk factors. Area under the curve (AUC) analysis was used to evaluate the discriminative ability of the multivariable model. Results. Data from 203 patients (63 males and 140 females) with a mean age of 62 years (22 to 89) were analyzed. In 49 fractures, the calcar screw was considered to be malpositioned; in 154 it was in the optimal position. The rate of malpositioning was therefore 24% (49/203). No preoperative risk factor was found for malpositioning of the calcar screws. Only the neck-shaft angle was found to be related to the risk of screw malpositioning in a multivariate model (with an AUC of 0.72). For the fractures in which the neck-shaft angle was reduced to between 130° and 150°, 91% (133/46) of calcar screws were in the optimal position. Conclusion. The neck-shaft angle is the key factor for the appropriate positioning of calcar screws when treating a proximal humeral fracture with a locking plate. We recommend reducing the angle to between 130° and 150°. Cite this article: Bone Joint J 2020;102-B(12):1629–1635

Aims. The aim of this study was to estimate the 90-day risk of revision for periprosthetic femoral fracture associated with design features of cementless femoral stems, and to investigate the effect of a collar on this risk using a biomechanical in vitro model. Materials and Methods. A total of 337 647 primary total hip arthroplasties (THAs) from the United Kingdom National Joint Registry (NJR) were included in a multivariable survival and regression analysis to identify the adjusted hazard of revision for periprosthetic fracture following primary THA using a cementless stem. The effect of a collar in cementless THA on this risk was evaluated in an in vitro model using paired fresh frozen cadaveric femora. Results. The prevalence of early revision for periprosthetic fracture was 0.34% (1180/337 647) and 44.0% (520/1180) occurred within 90 days of surgery. Implant risk factors included: collarless stem, non-grit-blasted finish, and triple-tapered design. In the in vitro model, a medial calcar collar consistently improved the stability and resistance to fracture. Conclusion. Analysis of features of stem design in registry data is a useful method of identifying implant characteristics that affect the risk of early periprosthetic fracture around a cementless femoral stem. A collar on the calcar reduced the risk of an early periprosthetic fracture and this was confirmed by biomechanical testing. This approach may be useful in the analysis of other uncommon modes of failure after THA. Cite this article: Bone Joint J 2019;101-B:779–786

Aims. In recent years, the use of a collared cementless femoral prosthesis has risen in popularity. The design intention of collared components is to transfer some load to the resected femoral calcar and prevent implant subsidence within the cancellous bone of the metaphysis. Conversely, the load transfer for a cemented femoral prosthesis depends on the cement-component and cement-bone interface interaction. The aim of our study was to compare the three most commonly used collared cementless components and the three most commonly used tapered polished cemented components in patients aged ≥ 75 years who have undergone a primary total hip arthroplasty (THA) for osteoarthritis (OA). Methods. Data from the Australian Orthopaedic Association National Joint Replacement Registry from 1 September 1999 to 31 December 2022 were analyzed. Collared cementless femoral components and cemented components were identified, and the three most commonly used components in each group were analyzed. We identified a total of 11,278 collared cementless components and 47,835 cemented components. Hazard ratios (HRs) from Cox proportional hazards models, adjusting for age and sex, were obtained to compare the revision rates between the groups. Results. From six months postoperatively onwards, patients aged ≥ 75 years undergoing primary THA with primary diagnosis of OA have a lower risk of all-cause revision with collared cementless components than with a polished tapered cemented component (HR 0.78 (95% confidence interval 0.64 to 0.96); p = 0.018). There is no difference in revision rate prior to six months. Conclusion. Patients aged ≥ 75 years with a primary diagnosis of OA have a significantly lower rate of revision with the most common collared cementless femoral component, compared with the most common polished tapered cemented components from six months postoperatively onwards. The lower revision rate is largely due to a reduction in revisions for fracture and infection. Cite this article: Bone Joint J 2024;106-B(3 Supple A):121–129

The calcar femorale is a vertical plate of bone lying deep to the lesser trochanter and is formed as a result of traction of the iliopsoas which separates the femoral cortex into two distinct layers, the calcar femorale and the medial femoral cortex. They fuse together proximally to form the medial femoral neck. A stem placed centrally will abut against the calcar femorale with little or no space for cement. Clearing of the calcar will offer space for a cement layer, which will support the stem proximally on the posterior aspect. We compared two consecutive groups of Charnley low-friction arthroplasties, with and without clearing of the calcar. In 330 patients who had an arthroplasty without clearing the calcar, there were ten revisions for aseptic loosening of the stem and six other stems were considered ‘definitely loose’, giving a rate of failure of 4.8%. In 111 patients in whom the calcar was cleared there was only one revision for aseptic loosening and no stems were classed as ‘definitely loose’, giving a rate of failure of 0.9%. Survivorship analysis has again shown the need for long-term follow-up; the differences became clear after ten years but because of the relatively small numbers, statistical analysis is not yet applicable. We now clear the calcar femorale routinely and advocate optimal access to the medullary canal and insertion of the stem in the area of the piriform fossa

Metal meshes are used in revision surgery of the hip to contain impacted bone grafts in cases with cortical or calcar defects in order to provide rotational stability to the stem. However, the viability of bone allografts under these metal meshes has been uncertain. We describe the histological appearances of biopsies obtained from impacted bone allografts to the calcar contained by a metal mesh in two femoral reconstructions which needed further surgery at 24 and 33 months after the revision procedure. A line of osteoid and viable new bone was observed on the surface of necrotic trabeculae. Active bone marrow between these trabeculae showed necrotic areas in some medullary spaces with reparative fibrous tissue and isolated reactive lymphocytes. This is interpreted as reparative changes after revascularisation of the cancellous allografts. These pathological findings are similar to those reported in allografts contained by cortical host bone and support the hypothesis that incorporation of morcellised bone under metal meshes is not affected by these devices

Aims

The aim of this retrospective study was to assess the incidence of early periprosthetic femoral fracture (PFF) associated with Charnley-Kerboull (CK) femoral components cemented according to the ‘French paradox’ principles through the Hueter anterior approach (HAA) in patients older than 70 years.

1. The literature on fractures of the postero-superior aspect of the calcaneus is reviewed.

2. The mechanical distinction between "beak" fractures and avulsion fractures is questioned, and the dangers of a purely radiological diagnosis are stressed.

3. When a complete avulsion is suspected on clinical grounds, open reduction should be done.

1. Five cases of avulsion fracture of the calcaneus are reported.

2. The "beak" fracture of the calcaneus is thought to be a variant of the avulsion fracture and not a separate entity.

3. The variable attachment of the calcaneal tendon to the calcaneus is described, and its relationship to the different forms of avulsion fractures discussed.

4. Operative reduction and fixation are appropriate for young and active patients in order to restore full heel-cord function.

5. Attention is drawn to the risk of pressure necrosis of skin overlying a displaced fragment. Early operative correction may be required to prevent skin damage.

1. The clinical aspects of fifty-six patients with rupture of the tendo calcaneus are discussed, and the mechanism of injury is described.

2. Operative repair of the rupture is considered with a study of the results in twenty-eight patients.

1. Twenty patients with congenital short tendo calcaneus are described.

2. All were treated by tendon lengthening and followed up for one and a half to seven years.

We reviewed our experience of tibialis anterior transfer and anterior release for calcaneus deformity in 46 feet of 26 ambulant patients with myelomeningocele. At an average follow-up of 8.4 years (2 to 17.6) there were 89% who had satisfactory results; 64% of the patients having tibialis anterior transfers were able to stand on their toes. Hip abductor power was a good predictor of a functional transfer. Pre-operative trophic ulceration of the heel increased from 3.2% to 33% if surgery was delayed. Secondary deformities, two-thirds of them into valgus, developed in 76% of feet.

The thalamus is the part of the calcaneus that supports the posterior articular facet and continues forward, becoming thinner towards the groove of the sinus tarsi. The main displacements after fracture depend on 1) a primary fracture line dividing the bone into anterior and posterior fragments, and 2) a semilunar fragment in the thalamic region. In the operation advised the sinus tarsi is exposed and the semilunar fragment is reduced by rotation in the opposite direction and is fixed to the medial fragment (the sustenaculum tali not being displaced) by a transverse Kirschner wire. The two main fragments are fixed by an antero-posterior wire. Plaster is applied and is retained for twelve weeks. Weight-bearing is not permitted for the first four weeks. There were no major complications in fifty-eight operations. The anatomical results were good: restoration of the tuber-joint angle by reduction of the semilunar fragment was maintained. The functional results were very satisfactory: permanent disability was slight or mild.

1 . Paralytic talipes calcaneus and calcaneo-cavus are difficult deformities to correct and keep corrected. Many operations have been devised for this purpose.

2. Emslie's operation is a simple procedure by which satisfactory correction can be obtained and maintained. It can be modified to suit individual cases without altering the basic principles of the procedure and is physiologically sound.

3. Illustrative cases are described.

1. In a severe crush fracture of the calcaneus part of the lateral cortex may be displaced to lie under the tip of the lateral malleolus. This may cause local pain and tenderness, either by direct bony abutment or by compression of the peroneal tendons.

2. Such pain is usually relieved by excision of the tip of the lateral malleolus, a minor procedure.

3. Four of the five patients reported were completely relieved of lateral pain, and the fifth has only slight residual discomfort.

4. It is important to be aware of this lesion and not to advise subtalar or triple fusion when simple excision of the tip of the fibula would suffice.

1. A case of ossification and partial rupture of the tendo calcaneus is reported.

2. The possible etiology of the ossification and its relationship to the rupture is discussed.

1. Thirty-four cases of calcaneal osteotomy for mobile flat foot in nineteen patients are reviewed.

2. The function was markedly improved in seventeen of the nineteen patients.

3. The operation was successful in correcting the valgus deformity of the heel in thirty of the thirty-four feet. it was less successful in improving the longitudinal arch, especially when the flat foot deformity was severe.

1. Thirty-three children with thirty-eight feet affected by a cavo-varus deformity and treated by calcaneal osteotomy with concomitant stripping of plantar muscles were reviewed two to ten years after operation.

2. Out of twenty-six patients who were over eleven years old at the time of the review, fourteen (with eighteen feet) did not need any further treatment. In three other patients the deformity had recurred to a slight degree but did not warrant tarsal reconstruction. In the remaining nine patients the recurrence was marked and necessitated tarsal reconstruction.

3. The combined procedure is of value when there is progressive deformity in children too young for tarsal reconstruction.

Aims. We compared implant and patient survival following intraoperative periprosthetic femoral fractures (IOPFFs) during primary total hip arthroplasty (THA) with matched controls. Patients and Methods. This retrospective cohort study compared 4831 hips with IOPFF and 48 154 propensity score matched primary THAs without IOPFF implanted between 2004 and 2016, which had been recorded on a national joint registry. Implant and patient survival rates were compared between groups using Cox regression. Results. Ten-year stem survival was worse in the IOPFF group (p < 0.001). Risk of revision for aseptic loosening increased 7.2-fold following shaft fracture and almost 2.8-fold after trochanteric fracture (p < 0.001). Risk of periprosthetic fracture of the femur revision increased 4.3-fold following calcar-crack and 3.6-fold after trochanteric fracture (p < 0.01). Risk of instability revision was 3.6-fold after trochanteric fracture and 2.4-fold after calcar crack (p < 0.001). Risk of 90-day mortality following IOPFF without revision was 1.7-fold and 4.0-fold after IOPFF with early revision surgery versus uncomplicated THA (p < 0.001). Conclusion. IOPFF increases risk of stem revision and mortality up to ten years following surgery. The risk of revision depends on IOPFF subtype and mortality risk increases with subsequent revision surgery. Surgeons should carefully diagnose and treat IOPFF to minimize fracture progression and implant failure. Cite this article: Bone Joint J 2019;101-B:1199–1208