The increasing complexity of femoral fragility fractures: incidence, fracture patterns and management over a 10-year period.

INTRODUCTION: The purpose of this study was to determine whether there have been changes in the numbers and complexity of femoral fragility fractures presenting to our department over a period of 10 years. METHODS: Patients >60 years presenting with femoral fragility fractures to our institution in 2018-2019 (397 fractures) were compared with respect to demographic data, incidence rates, fracture classification and surgical management with a historical cohort from 2009-2010 (335 fractures). Pathological and high velocity fractures were excluded. RESULTS: The gender proportion and average age (83.1 vs. 82.7 years) was unchanged. The number of femoral fractures increased by 19% but the overall incidence in people >60 years fell by 6% (p = 0.41). The proportion of unstable trochanteric fractures (31A2 and A3) increased from 22% to 55% (p < 0.001). The proportion of displaced intracapsular fractures increased from 53% to 72% (p < 0.001). The incidence of stable trochanteric fractures fell from 12.4 to 7.3/10,000 patients>60 years (p = 0.0006) while the incidence of unstable trochanteric fractures (31A2 and 31A3) increased from 3.5 to 8.9/10,000 patients >60 years (p < 0.0001). The proportion of trochanteric fractures treated with an intramedullary (IM) nail increased from 9% to 35% (p = 0.0001). The number of shaft and distal femoral fractures increased by 41% although the incidence did not change significantly. Periprosthetic fractures comprised 70% of femoral shaft fractures in both cohorts. CONCLUSIONS: The increasing number and complexity of femoral fragility fractures, especially unstable trochanteric fractures and periprosthetic fractures, is likely to have an impact on implant use, theatre time and cost.

Forecasting Posttreatment Outcome of Hallux Valgus Surgery Patients.

BACKGROUND: Despite advancements in operative techniques and the extraordinary number of procedures described for correcting hallux valgus (HV), there is still uncertainty as to why some patients thrive postoperatively whereas others do not. This study aimed to investigate whether the postoperative outcome of HV surgery could be predicted from patient demographics or functional impairment at the time of referral. METHODS: The prospectively collected data, from 92 patients, were analyzed to determine whether patient demographics significantly influenced outcome 52 weeks after surgery. Potential relationships between socioeconomic deprivation and the outcome, as well as between preoperative functional impairment and postoperative improvement, were examined. The Manchester Oxford Foot Questionnaire (MOXFQ) and Scottish Index of Multiple Deprivation (SIMD) were used in this evaluation. RESULTS: None of the demographics studied were found to be statistically significant determinants of outcome. Preoperative MOXFQ scores for patients from the most deprived areas were significantly worse at the time of referral. Patients living in the least deprived postcodes experienced the lowest improvement in MOXFQ scores. Patients from the most deprived SIMD quintile achieved significantly higher improvement in MOXFQ-walking and standing compared to those from the least deprived quintile. A strong positive correlation was found between the preoperative MOXFQ scores and the improvement in the scores postoperatively. CONCLUSION: In this patient cohort, demographics could not be used to predict the postoperative outcome at week 52. Socioeconomic disparities seem to influence the timing of patients seeking surgery. Lower preoperative MOXFQ scores strongly correlate with a lesser degree of postoperative improvement. LEVEL OF EVIDENCE: Level III, retrospective study with prospective arm.

Patient-Related Outcome Measures (PROMs) With Nonoperative and Operative Management of Morton's Neuroma.

BACKGROUND: Morton's neuroma is associated with chronic pain and disability. There is a paucity of literature regarding patient-related outcome measures (PROMs) in patients managed nonoperatively. We sought to investigate nonoperative and operative management of Morton's neuroma using PROMs in patients with follow-up to 1 year. METHODS: We conducted a prospective observational study and collected data on all patients with a new diagnosis of Morton's neuroma treated from February 2016 until April 2018. Primary outcome measures were the Manchester-Oxford Foot Questionnaire (MOXFQ) for pain, EuroQoL (EQ) time trade-off (TTO), and EQ visual analog scale (VAS) taken preoperatively and at 52 weeks postoperatively. Forty-four patients were treated nonoperatively and 94 patients were treated operatively. RESULTS: Pretreatment and 52-week scores were 55.7 and 43.10 (nonoperative) and 63.7 and 40.1 (operative) for MOXFQ (pain), 0.72 and 0.82 (nonoperative) and 0.68 and 0.82 (operative) for EQ-TTO, and 71.5 and 76.2 (nonoperative) and 73.1 and 68.7 (operative) for EQ-VAS. There was a statistically significant improvement in MOXFQ (pain) in nonoperative (P = .02) and operative groups (P < .001). There was a statistically significant improvement in EQ-TTO in the operative group only (P = .01). CONCLUSION: This is the largest study investigating outcomes to 12 months of both nonoperative and operatively managed patients with Morton's neuroma. Both nonoperative and operative management lead to symptom improvement at 12 months. LEVEL OF EVIDENCE: Level III, comparative study.

A cadaveric study investigating the role of the anterior inferior tibio-fibular ligament and the posterior inferior tibio-fibular ligament in ankle fracture syndesmosis stability.

BACKGROUND: This cadaveric study aimed to investigate the role AITFL and PITFL have on preventing talar shift in ankle fractures, as well as investigating the role of AITFL reconstruction in preventing talar shift. METHODS: Twelve lower limb cadavers were used. Talar shift was measured following: Step 1- no ligaments cut; Step 2- entire deltoid ligament division; Step 3- group A (5 specimens) PITFL cut whilst group B (7 specimens) AITFL cut; Step 4- group A had AITFL divided whilst group B had PITFL cut. Reconstruction of the AITFL was performed using part of the superior extensor retinaculum as a local flap. Measurement of talar shift was then repeated. RESULTS: With no ligaments divided, mean talar shift was 0.8mm for group A and 0.7mm for group B. When the deltoid ligament was divided, mean talar shift for group A was 4.8mm compared to 4.7mm in group B (P=1.00). The mean shift in group A after PITFL division was 6.0mm, increasing the talar shift by an average of 1.2mm. In group B after AITFL division mean talar shift was 8.3mm (P=0.06), increasing talar shift by an average of 3.6mm. After division of the second tibiofibular ligament, mean talar shift in group A measured 10.0mm and in group B was 10.9mm (P=0.29). Three times more talar shift occurred after the AIFTL was divided compared to the PITFL (P=0.06). CONCLUSION: Consequently, repairing the PITFL in isolation (for example by fixation of a posterior malleolus avulsion fracture) may not adequately prevent talar shift; we feel consideration should also be given to reconstruction of the AITFL to augment the syndesmosis fixation, which may provide a stronger restoration of ankle stability. LEVEL OF CLINICAL EVIDENCE: 5.

Position of the rotator cuff footprint in relation to the centre of rotation of the humeral head.

BACKGROUND: The objective of the present study was to determine the size and position of the rotator cuff moment arms constructed from the cuff footprints, incident on the line of force acting through the humeral head. METHODS: Five humeri were dissected, leaving the footprints of the rotator cuff intact. Each of the rotator cuff footprints and the cartilage/calcar interface were digitized and the articular surface was scanned using a high precision surface laser scanner. All of the data were merged into the same coordinate system. The centroid of each cuff footprint, centroid of the articular surface of the humerus (G) and the centroid of the articular surface of the glenoid (P) were calculated. Moment arms were measured as the intersection of a perpendicular line of force from each footprint centroid onto the resultant line of force to the centroid of the Glenoid (P). RESULTS: The mean moment arms of the supraspinatus, infraspinatus and subscapularis muscles were incident close to the centroid (G), whereas teres minor was lateral to the centroid, consistently. CONCLUSIONS: The teres minor moment arm aligned distal to the centroid of the sphere, consistently. The results may provide an understanding of the function of each muscle as a mobilizer or stabilizer of the glenohumeral joint. Further investigation is necessary.

Acute Achilles tendon rupture: Do cast boots produce adequate equinus when used for functional rehabilitation?

Acute Achilles tendon rupture is frequently treated conservatively using functional rehabilitation protocols in which the ankle is held in equinus. Equinus is achieved using a variety of means including equinus casts and rigid boots with heel wedges. Concerns have been raised that rigid boots with heel wedges do not achieve adequate equinus. Patients presenting to our institutions with an acute Achilles tendon rupture were randomised to treatment with an equinus cast or rigid boot with heel wedges. After application of these lateral radiographs of the hindfoot and ankle were taken, and these used to measure tibiotalar angle (TTA), tibio-1st metatarsal angle (TMA) and posterior malleolar to calcaneal tip height (PCH). 15 patients were randomised to a rigid boot and 14 to an equinus cast. The mean TTA was 124° in the rigid boot group and 136° in the equinus cast group (p<0.001). The mean TMA was 134° in the rigid boot group and 147° in the equinus cast group (p<0.001). The mean PCH was 25mm in the rigid boot group and 15mm in the equinus cast group (p<0.05). Our results demonstrate that the rigid boots with heel wedges used in our institutions produce significantly less equinus than an equinus cast. Whilst the clinical relevance of this remains uncertain, clinicians should be aware that rigid boots with wedges and equinus casts may not achieve the same degree of Achilles tendon shortening.

A comparison of surgical exposures for posterolateral osteochondral lesions of the talar dome.

BACKGROUND: Perpendicular access to the posterolateral talar dome for the management of osteochondral defects is difficult. We examined exposure available from each of four surgical approaches. MATERIALS AND METHODS: Four surgical approaches were performed on 9 Thiel-embalmed cadavers: anterolateral approach with arthrotomy; anterolateral approach with anterior talo-fibular ligament (ATFL) release; anterolateral approach with antero-lateral tibial osteotomy; and anterolateral approach with lateral malleolus osteotomy. The furthest distance posteriorly allowing perpendicular access with a 2mm k-wire was measured. RESULTS: An anterolateral approach with arthrotomy provided a mean exposure of the anterior third of the lateral talar dome. A lateral malleolus osteotomy provided superior exposure (81.5% vs 58.8%) compared to an anterolateral tibial osteotomy. CONCLUSIONS: Only the anterior half of the lateral border of the talar dome could be accessed with an anterolateral approach without osteotomy. A fibular osteotomy provided best exposure to the posterolateral aspect of the talar dome.

Stability of Lisfranc injury fixation in Thiel Cadavers: Is routine fixation of the 1st and 3rd tarsometatarsal joint necessary?

BACKGROUND: There is debate as to whether a home run screw (medial cuneiform to 2nd metatarsal base) combined with k-wire fixation of the 4th & 5th tarsometatarsal joints is sufficient to stabilise Lisfranc injuries or if fixation of the 1st and 3rd tarsometatarsal joints is also required. Unlike the 2nd, 4th and 5th tarsometatarsal joints, stabilisation of the 1st and 3rd requires either intra-articular screw or an extra-articular plate which risk causing chondrolysis and/or osteoarthritis. The aims of this cadaveric study were to determine if routine fixation of the 1st and 3rd tarsometatarsal joints is necessary and to determine if a distal to proximal home run screw is adequate. METHODS: Using 8 Theil-embalmed specimens, measurements of tarsometatarsal joint dorsal displacement at each ray (1st-5th) and 1st-2nd metatarsal gaping were made during simulated weight bearing with sequential ligamentous injury and stabilisation to determine the contribution of anatomical structures and fixation to stability. RESULTS: At baseline, mean dorsal tarsometatarsal joint displacement of the intact specimens during simulated weight bearing (mm) was: 1st: 0.14, 2nd: 0.1, 3rd:0, 4th: 0, 5th: 0.14. The 1st-2nd intermetatarsal gap was 0mm. After transection of the Lisfranc ligament only, there was 1st-2nd intermetatarsal gaping (mean 4.5mm), but no increased dorsal displacement. After additional transection of all the tarsometatarsal joint ligaments, dorsal displacement increased at all joints (1st: 4.5, 2nd: 5.1, 3rd: 3.6, 4th: 2, 5th: 1.3). Stabilisation with the home run screw and 4th and 5th ray k-wires virtually eliminated all displacement. Further transection of the inter-metatarsal ligaments increased mean dorsal displacement of the 3rd ray to 2.5mm. K-wire fixation of the 3rd ray completely eliminated dorsal displacement. CONCLUSIONS: The results of this cadaveric study suggest that stabilising the medial cuneiform to the 2nd metatarsal base combined with stabilisation of the 4th and 5th tarsometatarsal joints with K-wires will stabilise the 1st and 3rd tarsometatarsal joints if the inter-metatarsal ligaments are intact. Thus 3rd TMTJ stability should be checked after stabilising the 2nd and 4/5th. Provided the intermetatarsal ligaments (3rd-4th) are intact, the 3rd ray does not need to be routinely stabilised.

A novel osteotomy in shoulder joint replacement based on analysis of the cartilage/metaphyseal interface.

BACKGROUND: The accuracy of reconstruction is thought to impact on functional outcome following glenohumeral joint arthroplasty. The objective of this study was to define an area of minimal anatomic variation at the cartilage/metaphyseal interface of the proximal humerus to optimize the osteotomy of the humeral head, enabling accurate reconstruction with a prosthetic component. METHODS: Hand held digitization and 3D surface laser scanning techniques were used to digitize 24 cadaveric arms and determine the normal geometry. Each humeral head was then examined to identify the most consistent anatomical landmarks for the ideal osteotomy plane to optimize humeral component positioning. FINDINGS: The novel, posterior referencing, osteotomy resulted in a mean increase in retroversion of only 0.4° when compared to the original geometry. A traditional anterior referencing osteotomy, by comparison, produced a mean increase in retroversion of 11°. In addition, the novel osteotomy only increased axial diameter by 0.71mm and head height by 0.02mm compared to an anterior referencing osteotomy (3.0mm and 2.7mm respectively). INTERPRETATION: The traditional osteotomy, referencing the anterior border of the cartilage/metaphyseal interface potentially resulted in an increase in prosthetic head size and retroversion. The novel osteotomy, referencing from the posterior cartilage/metaphyseal interface enabled a more accurate recovery of head geometry. Importantly, the increase in retroversion created by the traditional osteotomy was not replicated with the novel technique. Referencing from the posterior cartilage/metaphyseal interface produced a more reliable osteotomy, more closely matching the original humeral geometry. LEVEL OF EVIDENCE: Basic Science, Anatomic study, Computer model.

Humeral head arthroplasty and its ability to restore original humeral head geometry.

BACKGROUND: Modern prosthetic components are designed to enable restoration of proximal humeral morphology, provided that a precise osteotomy of the humeral head at the level of the anatomic neck is performed. To determine whether a simulated osteotomy and replacement arthroplasty with an idealized implant were able to restore original head geometry. MATERIALS AND METHODS: A handheld digitizer and surface laser scanner were used to digitize 24 humeri. Computer models were used to simulate an osteotomy, performed at the anterior cartilage-metaphyseal interface, and reconstruct the head with a spherical prosthetic head. The head diameter, radius of curvature, and inclination and retroversion angles were calculated for each specimen and compared with the original humeral head. RESULTS: The simulated osteotomy resulted in a 4.8° decrease in inclination (P < .01) and 11.3° increase in retroversion (P < .001). The radius of curvature in the coronal plane was not significantly different (P = .284). However, in the axial plane, the prosthesis was significantly larger than the original head for both head diameter (P < .001) and radius of curvature (P < .05). DISCUSSION: The study suggests that the humeral head is not a perfect segment of a sphere and an osteotomy along the anterior cartilage-metaphyseal interface does not remove only the proximal humeral articular surface. Even with a fully adaptable prosthetic implant, replacement arthroplasty is not able to restore original head geometry. CONCLUSIONS: Alterations to head geometry with the osteotomy described may alter the line of force through the prosthetic joint, producing eccentric loading at the glenoid, and contribute to early failure.

A three-dimensional analysis of humeral head retroversion.

INTRODUCTION: The anatomic neck of the humerus is used as a reference for the osteotomy in shoulder arthroplasty. Resection along the anterior portion of the cartilage/metaphyseal border is assumed to remove a cap of a sphere that can accurately be replaced with a spherical prosthetic implant oriented precisely to the original articular surface. The aim of this study was to determine the variability in retroversion of the cartilage/metaphyseal interface in the axial plane. METHODS: Surface topography data for 24 arms from deceased donors were collected by using a hand-held digitizer and a surface laser scanner. Data were combined into the same coordinate system and graphically presented. The humeral head was divided into 6 sections in the axial plane and the retroversion angle measured at each level with reference to the transepicondylar axis at the elbow. RESULTS: The mean retroversion of the humeral head at the midpoint between the superior and inferior margins was 18.6°. The angle increased as the position of the measurement moved superiorly to 22.5°. In contrast, the retroversion angle reduced as the position of measurement moved more inferiorly to 14.3°. DISCUSSION: The results suggest that the cartilage/metaphyseal interface is not circular encompassing a spherical cap of a sphere. Furthermore, there appears to be a clockwise torsion of the cartilage/metaphyseal interface about the transverse axis from its medial to lateral aspect. CONCLUSION: The cartilage/metaphyseal interface shows a degree of variability that makes it an unreliable landmark to perform an osteotomy when the anterior aspect of the interface is used.

The effects of medialization and anteromedialization of the tibial tubercle on patellofemoral mechanics and kinematics.

BACKGROUND: Medialization and anteromedialization of the tibial tubercle are used to correct patellar subluxation in adults. PURPOSE: To compare the effects of the 2 osteotomies on patellofemoral joint contact pressures and kinematics. STUDY DESIGN: Controlled laboratory study. METHODS: Tibial tubercle osteotomies were performed on 10 cadaveric human knees. The knees were tested between 0 degrees and 90 degrees of flexion while dynamic patellofemoral joint contact pressure and kinematic data were simultaneously obtained. Four conditions were tested: normal knee alignment, simulated increased Q angle, postmedialization of the tibial tubercle, and postanteromedialization of the tubercle. RESULTS: An increased Q angle laterally translated the patella, shifted force to the lateral facet, and increased patella contact pressures. Both medialization and anteromedialization partially corrected the abnormal contact pressures. Medialization partially corrected the shift of force to the lateral facet induced by an increased Q angle, whereas the anteromedialization could not. Both medialization and anteromedialization corrected the patella maltracking. CONCLUSION: Medialization and anteromedialization are equivalent in their ability to correct abnormal patellar mechanics and kinematics.

Accuracy and repeatability of a pressure measurement system in the patellofemoral joint.

The objective of this study was to assess how accurately and repeatably the Iscan system measures force and pressure in the natural patellofemoral joint. These measurements must be made to test widely held assumptions about the relationships between mechanics, pain and cartilage degeneration. We assessed the system's accuracy by using test rigs in a materials testing machine to apply known forces and force distributions across the sensor. The root mean squared error in measuring resultant force (for five trials at each of seven load levels) was 6.5 +/- 4.4% (mean +/- standard deviation over all trials at all load levels), while the absolute error was -5.5 +/- 5.6%. For force distribution, the root mean squared error (for five trials at each of five force distributions) was 0.86 +/- 0.58%, while the absolute error was -0.22 +/- 1.03%. We assessed the repeatability of the system's measurements of patellofemoral contact force, pressure and force distribution in four cadaver specimens loaded in continuous and static flexion. Variability in measurement (standard deviation expressed as a percentage of the mean) was 9.1% for resultant force measurements and 3.0% for force distribution measurements for static loads, and 7.3% for resultant force and 2.2% for force distribution measurements for continuous flexion. Cementing the sensor to the cartilage lowered readings of resultant force by 31 +/- 32% (mean +/- standard deviation), area by 24 +/- 13% and mean pressure by 9 +/- 34% (relative to the uncemented sensor). Maximum pressure measurement, however, was 24 +/- 43% higher in the cemented sensor than in the uncemented sensor. The results suggest that the sensor measures force distribution more accurately and repeatably than absolute force. A limitation of our work, however, is that the sensor must be cemented to the patellar articular surface to make the force distribution measurements, and our results suggest that this process reduces the accuracy of force, pressure and area measurements. Our results suggest that the Iscan system's pressure measurement accuracy and repeatability are comparable to that of Fuji Prescale film, but its advantages are that it is thinner than most Fuji Prescale film, it measures contact area more accurately and that it makes continuous measurements of force, pressure and area.